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1.  Basal Subtype of Invasive Breast Cancer is Associated with a Higher Risk of True Recurrence after Conventional Breast-Conserving Therapy 
Purpose
To determine whether breast cancer subtype is associated with patterns of ipsilateral breast tumor recurrence (IBTR), either true recurrence (TR) or elsewhere local recurrence (ELR), among women with pT1-T2 invasive breast cancer (IBC) who receive breast-conserving therapy (BCT)
Methods and Materials
From 1/1998 to 12/2003, 1223 women with pT1-T2N0-3 IBC were treated with BCT (lumpectomy + whole breast radiation). Ninety percent of patients received adjuvant systemic therapy, but none received trastuzumab. Biologic subtype was approximated using estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2): luminal A (ER+ or PR+ and HER-2-), luminal B (ER+ or PR+ and HER-2+), HER-2 (ER- and PR- and HER-2+), and basal (ER- and PR- and HER-2-). Imaging, pathology and operative reports were reviewed by two physicians independently, including an attending breast radiologist. Readers were blinded to subtype and outcome. TR was defined as IBTR within the same quadrant and within three centimeters of the primary tumor. All others were ELR.
Results
At median follow-up of 70 months, 24 patients developed IBTR (5-year cumulative incidence 1.6%), including 15 TR and 9 ELR. At 5 years, basal (4.4%) and HER-2 (9%) subtypes had a significantly higher incidence of TR compared with luminal B (1.2%) and luminal A (0.2%) subtypes (p<0.0001). On multivariate analysis, basal subtype (HR 4.8, p=0.01), younger age at diagnosis (HR 0.97, p=0.05), and increasing tumor size (HR 2.1. p=0.04) were independent predictors of TR. Only younger age (HR 0.95, p=0.01) significantly predicted for ELR.
Conclusions
Basal and HER2 subtypes are significantly associated with higher rates of TR among women with pT1-T2 IBC after BCT. Younger age predicts for both TR and ELR. Strategies to reduce TR in basal breast cancers, such as increased boost doses, concomitant radiation and chemotherapy, or targeted therapy agents, should be explored.
doi:10.1016/j.ijrobp.2011.02.061
PMCID: PMC3161144  PMID: 21601377
breast cancer; biologic subtype; basal; triple negative; local recurrence; true recurrence; elsewhere recurrence
2.  Sentinel lymph node biopsy at the time of mastectomy does not increase the risk of lymphedema: implications for prophylactic surgery 
Women diagnosed with or at high risk for breast cancer increasingly choose prophylactic mastectomy. It is unknown if adding sentinel lymph node biopsy (SLNB) to prophylactic mastectomy increases the risk of lymphedema. We sought to determine the risk of lymphedema after mastectomy with and without nodal evaluation. 117 patients who underwent bilateral mastectomy were prospectively screened for lymphedema. Perometer arm measurements were used to calculate weight-adjusted arm volume change at each follow-up. Of 234 mastectomies performed, 15.8 % (37/234) had no axillary surgery, 63.7 % (149/234) had SLNB, and 20.5 % (48/234) had axillary lymph node dissection (ALND). 88.0 % (103/117) of patients completed the LEFT-BC questionnaire evaluating symptoms associated with lymphedema. Multivariate analysis was used to assess clinical characteristics associated with increased weight-adjusted arm volume and patient-reported lymphedema symptoms. SLNB at the time of mastectomy did not result in an increased mean weight-adjusted arm volume compared to mastectomy without axillary surgery (p = 0.76). Mastectomy with ALND was associated with a significantly greater mean weight-adjusted arm volume change compared to mastectomy with SLNB (p < 0.0001) and without axillary surgery (p = 0.0028). Patients who underwent mastectomy with ALND more commonly reported symptoms associated with lymphedema compared to those with SLNB or no axillary surgery (p < 0.0001). Patients who underwent mastectomy with SLNB or no axillary surgery reported similar lymphedema symptoms. Addition of SLNB to mastectomy is not associated with a significant increase in measured or self-reported lymphedema rates. Therefore, SLNB may be performed at the time of prophylactic mastectomy without an increased risk of lymphedema.
doi:10.1007/s10549-012-2231-1
PMCID: PMC3563357  PMID: 22941538
Prophylactic mastectomy; Breast cancer-related lymphedema; Sentinel lymph node biopsy; Bilateral mastectomy; Arm swelling
3.  Functional Analysis of Leishmania Cyclopropane Fatty Acid Synthetase 
PLoS ONE  2012;7(12):e51300.
The single gene encoding cyclopropane fatty acid synthetase (CFAS) is present in Leishmania infantum, L. mexicana and L. braziliensis but absent from L. major, a causative agent of cutaneous leishmaniasis. In L. infantum, usually causative agent of visceral leishmaniasis, the CFAS gene is transcribed in both insect (extracellular) and host (intracellular) stages of the parasite life cycle. Tagged CFAS protein is stably detected in intracellular L. infantum but only during the early log phase of extracellular growth, when it shows partial localisation to the endoplasmic reticulum. Lipid analyses of L. infantum wild type, CFAS null and complemented parasites detect a low abundance CFAS-dependent C19Δ fatty acid, characteristic of a cyclopropanated species, in wild type and add-back cells. Sub-cellular fractionation studies locate the C19Δ fatty acid to both ER and plasma membrane-enriched fractions. This fatty acid is not detectable in wild type L. major, although expression of the L. infantum CFAS gene in L. major generates cyclopropanated fatty acids, indicating that the substrate for this modification is present in L. major, despite the absence of the modifying enzyme. Loss of the L. infantum CFAS gene does not affect extracellular parasite growth, phagocytosis or early survival in macrophages. However, while endocytosis is also unaffected in the extracellular CFAS nulls, membrane transporter activity is defective and the null parasites are more resistant to oxidative stress. Following infection in vivo, L. infantum CFAS nulls exhibit lower parasite burdens in both the liver and spleen of susceptible hosts but it has not been possible to complement this phenotype, suggesting that loss of C19Δ fatty acid may lead to irreversible changes in cell physiology that cannot be rescued by re-expression. Aberrant cyclopropanation in L. major decreases parasite virulence but does not influence parasite tissue tropism.
doi:10.1371/journal.pone.0051300
PMCID: PMC3519623  PMID: 23251490
4.  Genome-Wide Screen Identifies Drug-Induced Regulation of the Gene Giant Axonal Neuropathy (Gan) in a Mouse Model of Antiretroviral-Induced Painful Peripheral Neuropathy 
Painful peripheral neuropathy is a debilitating complication of the treatment of HIV with nucleoside reverse transcriptase inhibitors (NRTIs). Patients are living longer with these drugs; however many develop excruciating, unremitting, and often treatment-limiting neuropathy that is resistant to conventional pain management therapies. Improving patient comfort and quality of life is paramount and depends on a clearer understanding of this devastating side effect. The mechanisms underlying the development of NRTI-induced neuropathy, however, remain unclear. Using a mouse model of NRTI-induced neuropathy, the authors conducted an unbiased whole-genome microarray screen to identify molecular targets in the spinal dorsal horn, which is the location where integration of ascending sensory transmission and descending modulatory effects occur. Analysis of the microarray data identified a change in the gene giant axonal neuropathy 1 (Gan1). Mutation of this gene has been linked to the development of giant axonal neuropathy (GAN), a rare autosomal recessive condition characterized by a progressive sensorimotor neuropathy. Gan1 has not been previously linked to nerve pathologies in other populations. In this study, downregulation of the Gan1 gene and the gene protein product, gigaxonin, was validated via quantitative polymerase chain reaction ([qPCR] gene expression) and Western blot analyses (protein level). Our report is the first to suggest that Gan1 might be a novel molecular target in the development of NRTI-induced peripheral neuropathy with implications for new therapeutic approaches to preventing or reducing a significant side effect of HIV treatment.
doi:10.1177/1099800409332726
PMCID: PMC3513273  PMID: 19398414
microarray; painful peripheral neuropathy; chronic pain; gigaxonin; giant axonal neuropathy; HIV/AIDS; HAART; NRTI
5.  Chronic Intrinsic Transient Tracheal Occlusion Elicits Diaphragmatic Muscle Fiber Remodeling in Conscious Rodents 
PLoS ONE  2012;7(11):e49264.
Background
Although the prevalence of inspiratory muscle strength training has increased in clinical medicine, its effect on diaphragm fiber remodeling is not well-understood and no relevant animal respiratory muscle strength training-rehabilitation experimental models exist. We tested the postulate that intrinsic transient tracheal occlusion (ITTO) conditioning in conscious animals would provide a novel experimental model of respiratory muscle strength training, and used significant increases in diaphragmatic fiber cross-sectional area (CSA) as the primary outcome measure. We hypothesized that ITTO would increase costal diaphragm fiber CSA and further hypothesized a greater duration and magnitude of occlusions would amplify remodeling.
Methodology/Principal Findings
Sprague-Dawley rats underwent surgical placement of a tracheal cuff and were randomly assigned to receive daily either 10-minute sessions of ITTO, extended-duration, 20-minute ITTO (ITTO-20), partial obstruction with 50% of cuff inflation pressure (ITTO-PAR) or observation (SHAM) over two weeks. After the interventions, fiber morphology, myosin heavy chain composition and CSA were examined in the crural and ventral, medial, and dorsal costal regions. In the medial costal diaphragm, with ITTO, type IIx/b fibers were 26% larger in the medial costal diaphragm (p<0.01) and 24% larger in the crural diaphragm (p<0.05). No significant changes in fiber composition or morphology were detected. ITTO-20 sessions also yielded significant increases in medial costal fiber cross-sectional area, but the effects were not greater than those elicited by 10-minute sessions. On the other hand, ITTO-PAR resulted in partial airway obstruction and did not generate fiber hypertrophy.
Conclusions/Significance
The results suggest that the magnitude of the load was more influential in altering fiber cross-sectional area than extended-duration conditioning sessions. The results also indicated that ITTO was associated with type II fiber hypertrophy in the medial costal region of the diaphragm and may be an advantageous experimental model of clinical respiratory muscle strength training.
doi:10.1371/journal.pone.0049264
PMCID: PMC3486807  PMID: 23133678
6.  Development of a Data Collection Instrument for Violent Patient Encounters against Healthcare Workers 
Introduction:
Healthcare and social workers have the highest incidence of workplace violence of any industry. Assaults toward healthcare workers account for nearly half of all nonfatal injuries from occupational violence. Our goal was to develop and evaluate an instrument for prospective collection of data relevant to emergency department (ED) violence against healthcare workers.
Methods:
Participants at a high-volume tertiary care center were shown 11 vignettes portraying verbal and physical assaults and responded to a survey developed by the research team and piloted by ED personnel addressing the type and severity of violence portrayed. Demographic and employment groups were compared using the independent-samples Mann-Whitney U Test.
Results:
There were 193 participants (91 male). We found few statistical differences when comparing occupational and gender groups. Males assigned higher severity scores to acts of verbal violence versus females (mean M,F=3.08, 2.70; p<0.001). While not achieving statistical significance, subgroup analysis revealed that attending physicians rated acts of verbal violence higher than resident physicians, and nurses assigned higher severity scores to acts of sexual, verbal, and physical violence versus their physician counterparts.
Conclusion:
This survey instrument is the first tool shown to be accurate and reliable in characterizing acts of violence in the ED across all demographic and employment groups using filmed vignettes of violent acts. Gender and occupation of ED workers does not appear to play a significant role in perception of severity workplace violence.
doi:10.5811/westjem.2011.12.6795
PMCID: PMC3556953  PMID: 23358263
7.  Age, Breast Cancer Subtype Approximation, and Local Recurrence After Breast-Conserving Therapy 
Journal of Clinical Oncology  2011;29(29):3885-3891.
Purpose
Prior results of breast-conserving therapy (BCT) have shown substantial rates of local recurrence (LR) in young patients with breast cancer (BC).
Patients and Methods
We studied 1,434 consecutive patients with invasive BC who received BCT from December 1997 to July 2006. Ninety-one percent received adjuvant systemic therapy; no patients received trastuzumab. Five BC subtypes were approximated: estrogen receptor (ER) or progesterone receptor (PR) positive, HER2 negative, and grades 1 to 2 (ie, luminal A); ER positive or PR positive, HER2 negative, and grade 3 (ie, luminal B); ER or PR positive, and HER2 positive (ie, luminal HER2); ER negative, PR negative, and HER2 positive (ie, HER2); and ER negative, PR negative, and HER2 negative (ie, triple negative). Actuarial rates of LR were calculated by using the Kaplan-Meier method.
Results
Median follow-up was 85 months. Overall 5-year cumulative incidence of LR was 2.1% (95% CI, 1.4% to 3.0%). The 5-year cumulative incidence of LR was 5.0% (95% CI, 3.0% to 8.3%) for age quartile 23 to 46 years; 2.2% (95% CI, 1.0% to 4.6%) for ages 47 to 54 years; 0.9% (95% CI, 0.3% to 2.6%) for ages 55 to 63 years; and 0.6% (95% CI, 0.1% to 2.2%) for ages 64 to 88 years. The 5-year cumulative incidence of LR was 0.8% (95% CI, 0.4% to 1.8%) for luminal A; 2.3% (95% CI, 0.8% to 5.9%) for luminal B; 1.1% (95% CI, 0.2% 7.4%) for luminal HER2; 10.8% (95% CI, 4.6% to 24.4%) for HER2; and 6.7% (95% CI, 3.6% to 12.2%) for triple negative. On multivariable analysis, increasing age was associated with decreased risk of LR (adjusted hazard ratio, 0.97; 95% CI, 0.94 to 0.99; P = .009).
Conclusion
In the era of systemic therapy and BC subtyping, age remains an independent prognostic factor after BCT. However, the risk of LR for young women appears acceptably low.
doi:10.1200/JCO.2011.36.1105
PMCID: PMC3189090  PMID: 21900114
8.  COMPARISON OF DIFFERENT TRUNK ENDURANCE TESTING METHODS IN COLLEGE‐AGED INDIVIDUALS 
Objective:
Determine the reliability of two different modified (MOD1 and MOD2) testing methods compared to a standard method (ST) for testing trunk flexion and extension endurance.
Participants:
Twenty‐eight healthy individuals (age 26.4 ± 3.2 years, height 1.75 ± m, weight 71.8 ± 10.3 kg, body mass index 23.6 ± 3.4 m/kg2).
Method:
Trunk endurance time was measured in seconds for flexion and extension under the three different stabilization conditions. The MOD1 testing procedure utilized a female clinician (70.3 kg) and MOD2 utilized a male clinician (90.7 kg) to provide stabilization as opposed to the ST method of belt stabilization.
Results:
No significant differences occurred between flexion and extension times. Intraclass correlations (ICCs3,1) for the different testing conditions ranged from .79 to .95 (p <.000) and are found in Table 3. Concurrent validity using the ST flexion times as the gold standard coefficients were .95 for MOD1 and .90 for MOD2. For ST extension, coefficients were .91 and .80, for MOD1 and MOD2 respectively (p <.01).
Conclusions:
These methods proved to be a reliable substitute for previously accepted ST testing methods in normal college‐aged individuals. These modified testing procedures can be implemented in athletic training rooms and weight rooms lacking appropriate tables for the ST testing.
Level of Evidence:
3
PMCID: PMC3474305  PMID: 23091786
Core; stabilization; trunk endurance
9.  The Effect of Class II Transactivator Mutations on Bleomycin-Induced Lung Inflammation and Fibrosis 
IFN-γ expression increases during the inflammatory response after bleomycin injury in mice. IFN-γ deficiency attenuates lung inflammation and fibrosis. Because IFN-γ stimulates class II transactivator (CIITA) expression, which activates major histocompatibility class (MHC) II and represses collagen expression, it was hypothesized that CIITA mediates IFN-γ action after bleomycin injury. To test this hypothesis, two CIITA mouse lines, one carrying a mutation of the leucine-rich region of CIITA (CIITA C−/−) and one with a deletion extending into the GTP-binding domain (CIITA G−/−), were used. IFN-γ treatment of lung cells isolated from both strains of mice induced mutant CIITA expression, which did not activate MHC II transcription. Collagen expression was similar in both mutant mouse strains and comparable to C57BL/6 (wild-type) mice. When mice were exposed to intratracheal bleomycin, both strains of CIITA mutant mice retained body weight and altered inflammation at 14 days after bleomycin injury compared with bleomycin-treated wild-type mice. However, there was no difference in fibrosis as judged by histology, mRNA, and protein expression of lungs. Bronchoalveolar lavage cells from CIITA C−/− and C57BL/6 lungs were examined at 3, 7, and 14 days after bleomycin injury. CD4 mRNA expression in bronchoalveolar lavage cells was down-regulated, whereas IL-4 and IL-10 expression was up-regulated, in CIITA C−/− mice, indicating a diminished, skewed Th2 response. The expression of IFN-γ was the same in all mice tested. Combined, our data suggest that CIITA mutations altered the immune response without affecting fibrosis.
doi:10.1165/rcmb.2009-0416OC
PMCID: PMC3135849  PMID: 20705943
collagen; CIITA; IFN-γ; fibrosis; bleomycin
10.  Pompe disease gene therapy 
Human Molecular Genetics  2011;20(R1):R61-R68.
Pompe disease is an autosomal recessive metabolic myopathy caused by the deficiency of the lysosomal enzyme acid alpha-glucosidase and results in cellular lysosomal and cytoplasmic glycogen accumulation. A wide spectrum of disease exists from hypotonia and severe cardiac hypertrophy in the first few months of life due to severe mutations to a milder form with the onset of symptoms in adulthood. In either condition, the involvement of several systems leads to progressive weakness and disability. In early-onset severe cases, the natural history is characteristically cardiorespiratory failure and death in the first year of life. Since the advent of enzyme replacement therapy (ERT), the clinical outcomes have improved. However, it has become apparent that a new natural history is being defined in which some patients have substantial improvement following ERT, while others develop chronic disability reminiscent of the late-onset disease. In order to improve on the current clinical outcomes in Pompe patients with diminished clinical response to ERT, we sought to address the cause and potential for the treatment of disease manifestations which are not amenable to ERT. In this review, we will focus on the preclinical studies that are relevant to the development of a gene therapy strategy for Pompe disease, and have led to the first clinical trial of recombinant adeno-associated virus-mediated gene-based therapy for Pompe disease. We will cover the preliminary laboratory studies and rationale for a clinical trial, which is based on the treatment of the high rate of respiratory failure in the early-onset patients receiving ERT.
doi:10.1093/hmg/ddr174
PMCID: PMC3095055  PMID: 21518733
11.  A Standardized Method for Quantification of Developing Lymphedema in Patients Treated for Breast Cancer 
Purpose
The lack of standard method to quantify developing breast cancer related lymphedema (BCRL) impedes the progress in research and clinical practice. We therefore developed a simple and practical formula for quantifying both the asymmetry of upper extremities' volumes and their temporal changes.
Methods & Materials
We present the analysis of bilateral perometer measurements of the upper extremity in a series of 677 women who prospectively underwent lymphedema screening during their treatment for unilateral breast cancer at Massachusetts General Hospital between August 2005 and November 2008. Four sources of variation are analyzed: between repeated measurements on the same arm at the same session, between both arms at the baseline (pre-operative) visit, in follow-up measurements, and between patients. We analyze the effects of hand dominance, time since diagnosis and surgery, age, weight, and body mass index (BMI).
Results
The statistical distribution of variation of measurements suggests that the ratio of volume ratios is most appropriate for quantification of both asymmetry and temporal changes. Therefore, we present the formula for Relative Volume Change (RVC): RVC=(A2U1)/(U2A1)-1, where A1, A2 are arm volumes on the side of the treated breast at two different time points, and U1, U2 are volumes on the contralateral side. RVC is not significantly associated with hand dominance, age, or time since diagnosis. Baseline weight correlates (P=0.0016) with higher RVC; however, baseline BMI or weight changes over time do not.
Conclusions
We propose the use of RVC formula to assess the presence and the course of BCRL in clinical practice and research.
doi:10.1016/j.ijrobp.2010.01.001
PMCID: PMC2952286  PMID: 20605339
lymphedema; quantification; standardized method; perometer; breast cancer
12.  The Orthologue of Sjögren's Syndrome Nuclear Autoantigen 1 (SSNA1) in Trypanosoma brucei Is an Immunogenic Self-Assembling Molecule 
PLoS ONE  2012;7(2):e31842.
Primary Sjögren's Syndrome (PSS) is a highly prevalent autoimmune disease, typically manifesting as lymphocytic infiltration of the exocrine glands leading to chronically impaired lacrimal and salivary secretion. Sjögren's Syndrome nuclear autoantigen 1 (SSNA1 or NA14) is a major specific target for autoantibodies in PSS but the precise function and clinical relevance of this protein are largely unknown. Orthologues of the gene are absent from many of the commonly used model organisms but are present in Chlamyodomonas reinhardtii (in which it has been termed DIP13) and most protozoa. We report the functional characterisation of the orthologue of SSNA1 in the kinetoplastid parasite, Trypanosoma brucei. Both TbDIP13 and human SSNA1 are small coiled-coil proteins which are predicted to be remote homologues of the actin-binding protein tropomyosin. We use comparative proteomic methods to identify potential interacting partners of TbDIP13. We also show evidence that TbDIP13 is able to self-assemble into fibril-like structures both in vitro and in vivo, a property which may contribute to its immunogenicity. Endogenous TbDIP13 partially co-localises with acetylated α-tubulin in the insect procyclic stage of the parasite. However, deletion of the DIP13 gene in cultured bloodstream and procyclic stages of T. brucei has little effect on parasite growth or morphology, indicating either a degree of functional redundancy or a function in an alternative stage of the parasite life cycle.
doi:10.1371/journal.pone.0031842
PMCID: PMC3282761  PMID: 22363749
13.  Therapeutic Vaccination With Recombinant Adenovirus Reduces Splenic Parasite Burden in Experimental Visceral Leishmaniasis 
The Journal of Infectious Diseases  2012;205(5):853-863.
Therapeutic vaccines, when used alone or in combination therapy with antileishmanial drugs, may have an important place in the control of a variety of forms of human leishmaniasis. Here, we describe the development of an adenovirus-based vaccine (Ad5-KH) comprising a synthetic haspb gene linked to a kmp11 gene via a viral 2A sequence. In nonvaccinated Leishmania donovani–infected BALB/c mice, HASPB- and KMP11-specific CD8+ T cell responses were undetectable, although IgG1 and IgG2a antibodies were evident. After therapeutic vaccination, antibody responses were boosted, and IFNγ+CD8+ T cell responses, particularly to HASPB, became apparent. A single vaccination with Ad5-KH inhibited splenic parasite growth by ∼66%, a level of efficacy comparable to that observed in early stage testing of clinically approved antileishmanial drugs in this model. These studies indicate the usefulness of adenoviral vectors to deliver leishmanial antigens in a potent and host protective manner to animals with existing L. donovani infection.
doi:10.1093/infdis/jir842
PMCID: PMC3274377  PMID: 22301630
14.  The feasibility of using natural language processing to extract clinical information from breast pathology reports 
Objective:
The opportunity to integrate clinical decision support systems into clinical practice is limited due to the lack of structured, machine readable data in the current format of the electronic health record. Natural language processing has been designed to convert free text into machine readable data. The aim of the current study was to ascertain the feasibility of using natural language processing to extract clinical information from >76,000 breast pathology reports.
Approach and Procedure:
Breast pathology reports from three institutions were analyzed using natural language processing software (Clearforest, Waltham, MA) to extract information on a variety of pathologic diagnoses of interest. Data tables were created from the extracted information according to date of surgery, side of surgery, and medical record number. The variety of ways in which each diagnosis could be represented was recorded, as a means of demonstrating the complexity of machine interpretation of free text.
Results:
There was widespread variation in how pathologists reported common pathologic diagnoses. We report, for example, 124 ways of saying invasive ductal carcinoma and 95 ways of saying invasive lobular carcinoma. There were >4000 ways of saying invasive ductal carcinoma was not present. Natural language processor sensitivity and specificity were 99.1% and 96.5% when compared to expert human coders.
Conclusion:
We have demonstrated how a large body of free text medical information such as seen in breast pathology reports, can be converted to a machine readable format using natural language processing, and described the inherent complexities of the task.
doi:10.4103/2153-3539.97788
PMCID: PMC3424662  PMID: 22934236
Breast pathology reports; clinical decision support; natural language processing
15.  Impaired Economy of Gait and Decreased Six-Minute Walk Distance in Parkinson's Disease 
Parkinson's Disease  2011;2012:241754.
Changes in the biomechanics of gait may alter the energy requirements of walking in Parkinson's Disease (PD). This study investigated economy of gait during submaximal treadmill walking in 79 subjects with mild to moderate PD and the relationship between gait economy and 6-minute walk distance (6 MW). Oxygen consumption (VO2) at the self-selected treadmill walking speed averaged 64% of peak oxygen consumption (VO2 peak). Submaximal VO2 levels exceeded 70% of VO2 peak in 30% of the subjects. Overall the mean submaximal VO2 was 51% higher than VO2 levels expected for the speed and grade consistent with severe impairment in economy of gait. There was an inverse relationship between economy of gait and 6MW (r = −0.31, P < 0.01) and with the self-selected walking speed (r = −0.35, P < 0.01). Thus, the impairment in economy of gait and decreased physiologic reserve result in routine walking being performed at a high percentage of VO2 peak.
doi:10.1155/2012/241754
PMCID: PMC3171762  PMID: 21922051
16.  Prediction of Cardiorespiratory Fitness in Older Men Infected with the Human Immunodeficiency Virus: Clinical Factors and Value of the Six-Minute Walk Distance 
OBJECTIVES
To investigate factors related to cardiorespiratory fitness in older human immunodeficiency virus (HIV)-infected patients and to explore the utility of 6-minute walk distance (6-MWD) in measuring fitness.
DESIGN
Cross-sectional study in clinic-based cohort.
SETTING
Veterans Affairs Medical Center, Baltimore, Maryland.
PARTICIPANTS
Forty-three HIV-infected men, median age 57 (range 50–82), without recent acquired immunodeficiency syndrome–related illness and receiving antiretroviral (ARV) therapy.
MEASUREMENTS
Peak oxygen utilization (VO2peak) according to treadmill graded exercise testing, 6-MWD, grip strength, quadriceps maximum voluntary isometric contraction, cross-sectional area, muscle quality, and muscle adiposity.
RESULTS
There was a moderate correlation between VO2peak (mean ± SD; 18.4 ± 5.6 mL/kg per minute) and 6-MWD (514 ± 91 m) (r = 0.60, P<.001). VO2peak was lower in subjects with hypertension (16%, P<.01) and moderate anemia (hemoglobin 10–13 gm/dL; 15%, P = .09) than in subjects without these conditions. CD4 cell count (median 356 cells/mL, range 20–1,401) and HIV-1 viral load (84% nondetectable) were not related to VO2peak. Among muscle parameters, only grip strength was an independent predictor of VO2peak. Estimation of VO2peak using linear regression, including age, 6-MWD, grip strength, and hypertension as independent variables, explained 61% of the variance in VO2peak.
CONCLUSION
Non-AIDS-related comorbidity predicts cardiorespiratory fitness in older HIV-infected men receiving ARV therapy. The 6-MWD is a valuable measure of fitness in this patient population, but a larger study with diverse subjects is needed.
doi:10.1111/j.1532-5415.2009.02495.x
PMCID: PMC3049945  PMID: 19793156
HIV; AIDS; cardiorespiratory fitness; physical function
17.  Inspiratory muscle strength training improves weaning outcome in failure to wean patients: a randomized trial 
Critical Care  2011;15(2):R84.
Introduction
Most patients are readily liberated from mechanical ventilation (MV) support, however, 10% - 15% of patients experience failure to wean (FTW). FTW patients account for approximately 40% of all MV days and have significantly worse clinical outcomes. MV induced inspiratory muscle weakness has been implicated as a contributor to FTW and recent work has documented inspiratory muscle weakness in humans supported with MV.
Methods
We conducted a single center, single-blind, randomized controlled trial to test whether inspiratory muscle strength training (IMST) would improve weaning outcome in FTW patients. Of 129 patients evaluated for participation, 69 were enrolled and studied. 35 subjects were randomly assigned to the IMST condition and 34 to the SHAM treatment. IMST was performed with a threshold inspiratory device, set at the highest pressure tolerated and progressed daily. SHAM training provided a constant, low inspiratory pressure load. Subjects completed 4 sets of 6-10 training breaths, 5 days per week. Subjects also performed progressively longer breathing trials daily per protocol. The weaning criterion was 72 consecutive hours without MV support. Subjects were blinded to group assignment, and were treated until weaned or 28 days.
Results
Groups were comparable on demographic and clinical variables at baseline. The IMST and SHAM groups respectively received 41.9 ± 25.5 vs. 47.3 ± 33.0 days of MV support prior to starting intervention, P = 0.36. The IMST and SHAM groups participated in 9.7 ± 4.0 and 11.0 ± 4.8 training sessions, respectively, P = 0.09. The SHAM group's pre to post-training maximal inspiratory pressure (MIP) change was not significant (-43.5 ± 17.8 vs. -45.1 ± 19.5 cm H2O, P = 0.39), while the IMST group's MIP increased (-44.4 ± 18.4 vs. -54.1 ± 17.8 cm H2O, P < 0.0001). There were no adverse events observed during IMST or SHAM treatments. Twenty-five of 35 IMST subjects weaned (71%, 95% confidence interval (CI) = 55% to 84%), while 16 of 34 (47%, 95% CI = 31% to 63%) SHAM subjects weaned, P = .039. The number of patients needed to be treated for effect was 4 (95% CI = 2 to 80).
Conclusions
An IMST program can lead to increased MIP and improved weaning outcome in FTW patients compared to SHAM treatment.
Trial Registration
ClinicalTrials.gov: NCT00419458
doi:10.1186/cc10081
PMCID: PMC3219341  PMID: 21385346
18.  Leishmania-Specific Surface Antigens Show Sub-Genus Sequence Variation and Immune Recognition 
Background
A family of hydrophilic acylated surface (HASP) proteins, containing extensive and variant amino acid repeats, is expressed at the plasma membrane in infective extracellular (metacyclic) and intracellular (amastigote) stages of Old World Leishmania species. While HASPs are antigenic in the host and can induce protective immune responses, the biological functions of these Leishmania-specific proteins remain unresolved. Previous genome analysis has suggested that parasites of the sub-genus Leishmania (Viannia) have lost HASP genes from their genomes.
Methods/Principal Findings
We have used molecular and cellular methods to analyse HASP expression in New World Leishmania mexicana complex species and show that, unlike in L. major, these proteins are expressed predominantly following differentiation into amastigotes within macrophages. Further genome analysis has revealed that the L. (Viannia) species, L. (V.) braziliensis, does express HASP-like proteins of low amino acid similarity but with similar biochemical characteristics, from genes present on a region of chromosome 23 that is syntenic with the HASP/SHERP locus in Old World Leishmania species and the L. (L.) mexicana complex. A related gene is also present in Leptomonas seymouri and this may represent the ancestral copy of these Leishmania-genus specific sequences. The L. braziliensis HASP-like proteins (named the orthologous (o) HASPs) are predominantly expressed on the plasma membrane in amastigotes and are recognised by immune sera taken from 4 out of 6 leishmaniasis patients tested in an endemic region of Brazil. Analysis of the repetitive domains of the oHASPs has shown considerable genetic variation in parasite isolates taken from the same patients, suggesting that antigenic change may play a role in immune recognition of this protein family.
Conclusions/Significance
These findings confirm that antigenic hydrophilic acylated proteins are expressed from genes in the same chromosomal region in species across the genus Leishmania. These proteins are surface-exposed on amastigotes (although L. (L.) major parasites also express HASPB on the metacyclic plasma membrane). The central repetitive domains of the HASPs are highly variant in their amino acid sequences, both within and between species, consistent with a role in immune recognition in the host.
Author Summary
Single-celled Leishmania parasites, transmitted by sand flies, infect humans and other mammals in many tropical and sub-tropical regions, giving rise to a spectrum of diseases called the leishmaniases. Species of parasite within the Leishmania genus can be divided into two groups (referred to as sub-genera) that are separated by up to 100 million years of evolution yet are highly related at the genome level. Our research is focused on identifying gene differences between these sub-genera that may identify proteins that impact on the transmission and pathogenicity of different Leishmania species. Here we report the presence of a highly-variant genomic locus (OHL) that was previously described as absent in parasites of the L. (Viannia) subgenus (on the basis of lack of key genes) but is present and well-characterised (as the LmcDNA16 locus) in all members of the alternative subgenus, L. (Leishmania). We demonstrate that the proteins encoded within the LmcDNA16 and OHL loci are similar in their structure and surface localisation in mammalian-infective amastigotes, despite significant differences in their DNA sequences. Most importantly, we demonstrate that the OHL locus proteins, like the HASP proteins from the LmcDNA16 locus, contain highly variable amino acid repeats that are antigenic in man and may therefore contribute to future vaccine development.
doi:10.1371/journal.pntd.0000829
PMCID: PMC2946902  PMID: 20927190
19.  Increases in Whole Blood Glucose Measurements Using Optically Based Self-Monitoring of Blood Glucose Analyzers Due to Extreme Canadian Winters 
Background
Temperature and humidity have been reported to influence the results of whole blood glucose (WBG) measurements.
Methods
To determine whether patient WBG values were affected by seasonal variation, we conducted a retrospective analysis of 3 years' worth of weekly averages of patient WBG in five Edmonton hospitals.
Results
In all five hospitals, the winter WBG averages were consistently higher than the summer WBG averages, with the differences varying between 5% and 9%. Whole blood glucose averages were negatively correlated with the outside temperature. This seasonal variation was not observed in weekly patient averages of specimens run in a central hospital laboratory.
Interpretation
It is probable that the seasonal variation of WBG arises from the very low indoor humidities that are associated with external subzero temperatures. These increases in WBG in cold weather may be due to limitations in the WBG measuring systems when operated in decreased humidities and/or increased evaporation of the blood sample during the blood glucose measurement process. The implications of this seasonal variation are significant in that it (1) introduces increased variability in patient WBG, (2) may result in increased glucose-lowering therapy during periods of external cold and low indoor humidity, and (3) confounds evaluations of WBG meter technology in geographic regions of subzero temperature and low indoor humidity. To mitigate the risk of diagnosing and treating factitious hyperglycemia, the humidity of patient care areas must be strictly controlled.
PMCID: PMC2769945  PMID: 20144309
diabetes; environmental effects; humidity; whole blood glucose monitoring
20.  Elbow Joint Active Replication in College Pitchers Following Simulated Game Throwing 
Sports Health  2010;2(4):345-350.
Background:
Elbow injuries are common in college baseball players. Pitching creates stress and fatigue in and around the elbow. Lack of joint proprioception can contribute to nonphysiological joint loading and injury.
Hypothesis:
There will be no difference in elbow joint active reproduction sense following a simulated 3-inning pitching sequence.
Study Design:
Cross-sectional study.
Methods:
Seventeen collegiate pitchers participated. Each pitcher was bilaterally tested for active elbow range of motion using goniometric technique. Percentages of motion determined positions for further study of elbow joint active replication sense (20%, 35%, 50%, 80%). The elbow was passively taken to a position and held for 10 seconds, then returned to full extension. Pitchers were asked to actively reproduce the angle. The opposite elbow was tested in the same manner. One week later, prethrowing joint position reproduction was tested; then a simulated 3-inning game was thrown. Immediately afterward, elbow joint active replication testing was performed. A repeated-measures analysis of variance analyzed differences.
Results:
No change in active joint reproduction occurred in the nondominant elbow at any angle tested. Dominant elbows demonstrated significant losses of active joint reproduction following throwing. Significant differences occurred at the 35% and 80% angles (P < .05).
Conclusion:
Active elbow joint replication sense may be compromised following 3 innings of throwing. Because joint proprioception is thought to be an important component of joint stabilization, an alteration in joint position sense may increase the risk of elbow injury during throwing.
Clinical Relevance:
Pitching may cause a loss of active elbow joint replication.
doi:10.1177/1941738110365119
PMCID: PMC3445087  PMID: 23015958
elbow; proprioception; pitching
21.  Regulating the Activity of Class II Transactivator by Posttranslational Modifications: Exploring the Possibilities▿  
Molecular and Cellular Biology  2009;29(21):5639-5644.
First identified as the master regulator of major histocompatibility complex II transcription, class II transactivator (CIITA) has since been implicated in a host of pathologies by modulating the transcription of multiple different genes. How CIITA caters to cell- and tissue-specific transcriptional needs is hotly debated and investigated. One of the possible mechanisms underlying spatiotemporal control of CIITA transcriptional activity is the posttranslational modification (PTM) machinery that refines certain amino acid residues of CIITA and hence alters its activity in response to specific cellular and environmental cues. This review discusses our current understanding of the PTM map of CIITA, how these modifications fine-tune its activity, and how the study of this area may lead to potential therapeutic strategies.
doi:10.1128/MCB.00661-09
PMCID: PMC2772741  PMID: 19720744
22.  N-Myristoyltransferase from Leishmania donovani: Structural and Functional Characterisation of a Potential Drug Target for Visceral Leishmaniasis 
Journal of Molecular Biology  2010;396(4):985-999.
N-Myristoyltransferase (NMT) catalyses the attachment of the 14-carbon saturated fatty acid, myristate, to the amino-terminal glycine residue of a subset of eukaryotic proteins that function in multiple cellular processes, including vesicular protein trafficking and signal transduction. In these pathways, N-myristoylation facilitates association of substrate proteins with membranes or the hydrophobic domains of other partner peptides. NMT function is essential for viability in all cell types tested to date, demonstrating that this enzyme has potential as a target for drug development. Here, we provide genetic evidence that NMT is likely to be essential for viability in insect stages of the pathogenic protozoan parasite, Leishmania donovani, causative agent of the tropical infectious disease, visceral leishmaniasis. The open reading frame of L. donovaniNMT has been amplified and used to overproduce active recombinant enzyme in Escherichia coli, as demonstrated by gel mobility shift assays of ligand binding and peptide-myristoylation activity in scintillation proximity assays. The purified protein has been crystallized in complex with the non-hydrolysable substrate analogue S-(2-oxo)pentadecyl-CoA, and its structure was solved by molecular replacement at 1.4 Å resolution. The structure has as its defining feature a 14-stranded twisted β-sheet on which helices are packed so as to form an extended and curved substrate-binding groove running across two protein lobes. The fatty acyl-CoA is largely buried in the N-terminal lobe, its binding leading to the loosening of a flap, which in unliganded NMT structures, occludes the protein substrate binding site in the carboxy-terminal lobe. These studies validate L. donovani NMT as a potential target for development of new therapeutic agents against visceral leishmaniasis.
doi:10.1016/j.jmb.2009.12.032
PMCID: PMC2829124  PMID: 20036251
ARF, ADP-ribosylation factor; DIG, digoxigenin; HASP, hydrophilic acylated surface protein; HYG, hygromycin; NEO, neomycin; NHM, non-hydrolysable myristoyl-CoA analogue; NMT, N-myristoyltransferase; ORF, open reading frame; PAC, puromycin; SPA, scintillation proximity assay; VL, visceral leishmaniasis; CaNMT, HsNMT, LdNMT and ScNMT, N-myristoyltransferase from Candida albicans, Homo sapiens, Leishmania donovani and Saccharomyces cerevisiae, respectively; N-myristoyltransferase; Leishmania; visceral leishmaniasis; crystal structure; drug target
23.  Significant Impairment in Immune Recovery Following Cancer Treatment 
Nursing research  2009;58(2):105-114.
Background
Although immunosuppression from cancer adjuvant therapy has been documented, how these suppressed immune responses recover to baseline values after completion of cancer adjuvant therapy has not been studied systematically.
Objectives
To examine the probability of immune recovery following cancer adjuvant therapy and the potential impact of cancer adjuvant therapy type and cancer stage on immune recovery in newly diagnosed breast cancer patients.
Method
In a repeated-measures design, immune responses were measured 4 times in 80 early stage breast cancer patients: prior to, and at 2, 6, and 12 months from the beginning of cancer adjuvant therapy. Natural killer cell activity (NKCA), lymphokine-activated killer cell activity, lymphocyte proliferation, CD subsets (CD4, CD8, and CD56), and cytokines (IFN-γ, IL-2, IL-4, IL-6, and IL-1α) were selected for their relevance to breast cancer. Immune recovery was defined by the level of immune response reaching to and above baseline levels. Data were analyzed using a multivariate generalized linear mixed model approach.
Results
Delayed immune recovery to pretreatment baseline levels continued to the 12-month time point in all parameters. The percentages of immune recovery ranged from 6% to 76% of the patients, varying among immune parameters. Overall, immune recovery was poorer for IFN-γ, IL-2, IL-4, lymphocyte proliferation and NKCA than for CD subsets and IL-6. The type of cancer adjuvant therapy, not cancer stage, showed selective influence on immune recovery. Chemotherapy or chemo- and radiotherapy combination significantly delayed IL-2 recovery, whereas radiotherapy significantly delayed IL-4 recovery.
Discussion
Immune recovery following breast cancer adjuvant therapy is delayed significantly for an extended time period in numerous immune parameters. The type of cancer adjuvant therapy has selective influence on immune recovery. Future investigations are warranted to elucidate the time course of immune recovery, clinical significance of poor immune recovery, and factors influencing immune recovery in order to develop potential interventions.
doi:10.1097/NNR.0b013e31818fcecd
PMCID: PMC2777669  PMID: 19289931
immune recovery; breast cancer; cancer treatment
24.  A Randomized Controlled Single-Blinded Comparison of Stretching Versus Stretching and Joint Mobilization for Posterior Shoulder Tightness Measured by Internal Rotation Motion Loss 
Sports Health  2010;2(2):94-100.
Background:
Posterior shoulder tightness, as demonstrated by limited internal rotation range of motion, is a suggested factor in many shoulder pathologies. Methods to increase posterior shoulder mobility may be beneficial.
Hypothesis:
Shoulder internal rotation range of motion will not change with either of 2 interventions: cross-body stretch alone and cross-body stretch plus posterior capsule joint mobilization.
Study Design:
Randomized controlled single-blinded clinical trial.
Methods:
The study comprised 39 college-age asymptomatic participants (7 men, 32 women) who were randomly assigned to 1 of 2 groups: stretching only (n, 20) and stretching plus posterior joint mobilizations (n, 19). All had a between-shoulder difference of internal rotation of 10° or more. Shoulder internal and external rotation was measured before and after a 4-week intervention period and 4 weeks postintervention. Participants in the stretching-only group performed the cross-body stretch on the limited side. Those in the other group (cross-body stretch plus joint mobilization) were treated with posterior joint mobilization techniques on the limited side.
Results:
Overall means for internal rotation of the treated shoulders significantly increased over baseline at the end of the intervention period and at 4 weeks postintervention. External rotation in all shoulders remained unchanged. By the end of intervention, total motion increased significantly from baseline but decreased significantly from the end of intervention to 4 weeks postintervention. Although not statistically significant, the second group (cross-body stretch plus joint mobilization) had greater increases in internal rotation. At 4 weeks postintervention, the second group had maintained its internal rotation gains to a greater degree than those of the stretching-only group.
Conclusion:
Internal rotation increased in both groups. Inclusion of joint mobilization in a rehabilitation program created trends toward increased shoulder internal rotation mobility.
Clinical Relevance:
Both methods—cross-body stretch and cross-body stretch plus joint mobilization—may be beneficial for those with limited internal rotation range of motion.
doi:10.1177/1941738109347775
PMCID: PMC3445079  PMID: 23015927
randomized controlled trial; shoulder; stretching; joint mobilization
25.  A distinct cellular profile is seen in the human endocervix during Chlamydia trachomatis infection 
Problem
The endocervix is a major target of Chlamydia trachomatis (CT) infection, but little is known about the immune repertoire in this tissue, or its response to these common bacteria.
Method of Study
Using a cytobrush, we isolated cells from the endocervix of 20 women during CT infection, and post-antibiotic treatment. Endocervical swabs and blood were taken in parallel. Endocervical cells were enumerated, and endocervical and blood T cells immunophenotyped. CT was genotyped by sequence analysis of the OmpA gene, and quantified by culture.
Results
CT genotypes were D, E, F and Ia, and infectious burden varied considerably. Endocervical T cell and neutrophil numbers were highly elevated during infection, with both CD4 and CD8 T cell subsets accumulating. Regardless of the presence or absence of infection, the endocervical cell infiltrate was dominated by effector memory T cells, and the numbers of CCR5 and CD103 expressing T cells was significantly higher than in the blood. HLA-DR expression by endocervical T cells was significantly increased during infection.
Conclusions
The human endocervix exhibits a distinct cellular response to C.trachomatis infection that can be longitudinally evaluated by cytobrush sampling. Infecting organisms can be sampled and analyzed in parallel.
doi:10.1111/j.1600-0897.2008.00639.x
PMCID: PMC2574558  PMID: 18798835
Chlamydia trachomatis; endocervix; human; T lymphocyte

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