We sought to measure the anatomic dimensions of the crista galli in a consecutive series of patients undergoing the endoscopic transcribriform approach for anterior skull base tumors at a tertiary academic university hospital. We performed a retrospective chart review of patients undergoing purely endoscopic transcribriform surgery for sinonasal and skull base lesions. Main outcome measures included radiological dimensions of the crista galli. A total of 12 patients were identified and treated by the senior authors at the University of Pennsylvania. The average crista galli dimensions were 12.7 ± 2.4 mm (anterior-posterior) and 12.9 ± 2.5 mm (cranial-caudal dimension). Knowledge of the dimensions of the crista galli is important in preoperative planning for both instrumentation and access.
doi:10.1055/s-0030-1263283
PMCID: PMC3312591
PMID: 22451806
Endoscopic skull base surgery; transcribriform; crista galli; radiology; anatomy
Purely endoscopic resections of transcranial/intracranial pathology represent an exciting minimally invasive option for some patients. There is an abundance of literature on surgical techniques, though very little deals with perioperative management, which is critical for good outcomes. We present a detailed case review and a perioperative management protocol with specific reference to skull base and neuroanatomy. We performed a retrospective chart review and analysis of outcomes and complications by approach and design and prospective employment of a perioperative management protocol in a major tertiary care referral hospital. We included patients undergoing endoscopic skull base approaches by the two senior surgeons from September 2005 to April 2009, selecting of transcranial/intracranial cases for detailed review. Our main outcome measures included perioperative morbidity, mortality, and complications; degree of resection; recurrence rate; and survival. Fifteen patients met study criteria. No perioperative mortality occurred. There were two major and four minor complications. Mean follow-up was 15 months; 11/13 patients with malignancies had no evidence of disease. A perioperative management protocol was designed from these data and has resulted in decreased lumbar drainage and increased fluid/electrolyte monitoring. Endoscopic transcranial/intracranial anterior skull base surgery is both safe and effective when a complete understanding of the surgery and perioperative management is achieved.
doi:10.1055/s-0030-1261265
PMCID: PMC3312415
PMID: 22451795
Extended endonasal approach; endoscopic; anterior skull base; skull base neoplasm
The purpose of this study was to evaluate the effects of functional communication training (FCT) on the occurrence of non-targeted disruptive behavior. The 10 participants were preschool-aged children with developmental disabilities who engaged in both destructive (property destruction, aggression, self-injury) and disruptive (hand flapping, spinning in circles, shrill laughter, screaming, crying) behaviors. Only destructive behavior was targeted for the functional analyses and FCT, but data were also collected on disruptive behaviors. All procedures were conducted in the participants’ homes by their mothers with investigator coaching. Phase 1 consisted of conducting a functional analysis within a multielement design. Phase 2 consisted of conducting FCT with demand fading and repeated extinction baselines within a reversal design. Single-case data are provided for 3 participants, and summary data are provided for all 10 participants. Results of phase 1 showed that all participants’ destructive and disruptive behavior was maintained, at least in part, by negative reinforcement. Results of phase 2 showed that both destructive behavior and non-targeted disruptive behavior occurred at lower levels during FCT when compared to the functional analysis demand condition and baseline conditions, suggesting that FCT was effective in decreasing both target destructive behavior and non-targeted disruptive behaviors.
PMCID: PMC3594102
PMID: 23487563
Functional analysis; Functional communication training; Destructive behavior; Developmental disabilities; Long-term treatment
Olkhanud, Purevdorj B. | Mughal, Mohammed | Ayukawa, Koichi | Malchinkhuu, Enkhzol | Bodogai, Monica | Feldman, Neil | Rothman, Sarah | Lee, John | Chigurupati, Srinivasulu | Okun, Eitan | Nagashima, Kunio | Mattson, Mark P. | Biragyn, Arya
Alzheimer's disease (AD) is an incurable and progressive neurodegenerative senile disorder associated with the brain accumulation of Aβ plaques. Although vaccines that reduce Aβ plaques can control AD, the rationale for their use at the onset of the disease remains debatable. Old humans and mice usually respond poorly to vaccines due to presumably age-related immunological impairments. Here, we report that by modifying vaccines, the poor responsiveness of old mice can be reversed. Unlike the Aβ peptide vaccine, DNA immunizations with the amino-terminal Aβ(1-11) fragment exposed on the surface of HBsAg particles elicit high levels of anti-Aβ antibody both in young and old mice. Importantly, in AD model 3xTgAD mice, the vaccine reduced Aβ plaques, ameliorated cognitive impairments and, surprisingly, significantly increased life span. Hence, we propose that vaccines targeting Aβ(1-11) can efficiently combat AD-induced pathological alterations and provide survival benefit in patients with AD.
doi:10.1016/j.vaccine.2011.12.136
PMCID: PMC3278568
PMID: 22248819
Aβ; Alzheimer's disease vaccine; old age; life span
Immune reconstitution inflammatory syndrome (IRIS) refers to the presence of paradoxical clinical deterioration attributable to immune system recovery during highly active antiretroviral therapy (HAART). We present an immunocompetent patient with multifocal leukoencephalopathy on HAART, with central nervous system (CNS) IRIS pathology of unknown infectious etiology. CNS IRIS pathology should be suspected in patients on longstanding HAART without immune reconstitution, presenting with unexplained leukoencephalopathy.
doi:10.3389/fneur.2013.00012
PMCID: PMC3578199
PMID: 23439663
IRIS; multifocal leukoencephalopathy; AIDS; HIV; seizures
Enzymes in lipid metabolism acquire and deliver hydrophobic substrates and products from within lipid bilayers. The structure at 2.55 Å of one isozyme of a constitutive enzyme in lipid A biosynthesis, LpxI from Caulobacter crescentus, has a novel fold. Two domains close around a completely sequestered substrate, UDP-2,3-diacylglucosamine, and open to release products either to the neighboring enzyme in a putative multi-enzyme complex, or to the bilayer. Mutation identifies Asp225 as key to Mg2+ catalyzed diphosphate hydrolysis. These structures provide snapshots of the enzymatic synthesis of a critical lipid A precursor.
doi:10.1038/nsmb.2393
PMCID: PMC3562136
PMID: 23042606
In order to construct a novel vaccine candidate for preventing post-weaning diarrhea in swine, the individual genes for Escherichia coli K88ab, K88ac, FedA, and FedF fimbriae were inserted into a secretion plasmid pBP244 containing asd, lepB, secA, and secB. These were transformed into Salmonella Typhimurium Δlon ΔcpxR Δasd. Secretion of the individual recombinant fimbrial antigens was confirmed by immunoblot analysis. Groups 1 and 2 mice received a single oral dose of the vaccine mixture and S. Typhimurium carrying pBP244 only as a control, respectively. In groups 3 and 4, mice were primed and boosted with the vaccine mixture and S. Typhimurium carrying pBP244 only as a control, respectively. In general, all immunized mice had significantly increased serum immunoglobulin (Ig)G (P < 0.05) and intestinal secretory IgA against the individual fimbrial antigens compared with those mice in the control group. In the IgG2a and IgG1 titer assay, only IgG2a titer was increased in group 1, while both IgG2a and IgG1 titers were increased in group 3. Furthermore, the vaccine strains were not detected in the excreted feces of any immunized mice. Thus, the vaccine candidate can be highly immunogenic and be safe to the environment.
PMCID: PMC3384281
PMID: 23277697
Double balloon enteroscopy (DBE) is a revolutionary procedure in which the entire small bowel can be visualized endoscopically. DBE has the advantage of both diagnostic and therapeutic capabilities in the setting of small bowel neoplasms and vascular malformations. We present a unique case of a 76-year-old female who underwent small bowel DBE tattoo marking of a distal small bowel tumor complicated by development of severe abdominal pain postprocedure secondary to bowel air embolism into the mesenteric veins. Mesenteric air can be seen after other endoscopic procedures such as biopsy, mucosal clip placement and polypectomy, or following a colonoscopy. Mesenteric air embolism following small bowel tattooing procedure has not been previously reported in the literature. Mesenteric air when present may be attributed to mesenteric ischemia and can subject the patient to unnecessary surgical intervention if misdiagnosed. Thus, this report holds significance for the radiologist as computed tomography (CT) findings of mesenteric air embolism must be evaluated in the context of appropriate clinical history before treatment decisions are made.
doi:10.4103/2156-7514.105270
PMCID: PMC3551506
PMID: 23393642
CT air embolism; mesenteric air embolism; small bowel tattoo
Summary
Most of the 231 unique membrane protein structures (as of 3/2010) are of bacterial membrane proteins (MPs) expressed in bacteria, or eukaryotic MPs from natural sources. However eukaryotic membrane proteins, especially those with more than three membrane crossings rarely succumb to any suitable expression in bacterial cells. They typically require expression in eukaryotic cells that can provide appropriate endoplasmic reticulum, chaperones, targeting and post-translational processing. In evidence, only ~20 eukaryotic MP structures have resulted from heterologous expression. This is required for a general approach to target particular human or pathogen membrane proteins of importance to human health. The first of these appeared in 2005. Our review addresses the special issues that pertain to the expression of eukaryotic and human membrane proteins, and recent advances in the tool kit for crystallization and structure determination.
doi:10.1016/j.sbi.2010.05.004
PMCID: PMC3530418
PMID: 20739007
Background
Nucleic acid aptamers have long demonstrated the capacity to bind viral envelope proteins and to inhibit the progression of pathogenic virus infections. Here we report on initial efforts to develop and screen DNA aptamers against recombinant envelope proteins or synthetic peptides and whole inactivated viruses from several virulent arboviruses including Chikungunya, Crimean-Congo hemorrhagic fever (CCHF), dengue, tickborne encephalitis and West Nile viruses. We also analyzed sequence data and secondary structures for commonalities that might reveal consensus binding sites among the various aptamers. Some of the highest affinity and most specific aptamers in the down-selected libraries were demonstrated to have diagnostic utility in lateral flow chromatographic assays and in a fluorescent aptamer-magnetic bead sandwich assay. Some of the reported aptamers may also be able to bind viral envelope proteins in vivo and therefore may have antiviral potential in passive immunity or prophylactic applications.
Results
Several arbovirus DNA aptamer sequences emerged multiple times in the various down selected aptamer libraries thereby suggesting some consensus sequences for binding arbovirus envelope proteins. Screening of aptamers by enzyme-linked aptamer sorbent assay (ELASA) was useful for ranking relative aptamer affinities against their cognate viral targets. Additional study of the aptamer sequences and secondary structures of top-ranked anti-arboviral aptamers suggest potential virus binding motifs exist within some of the key aptamers and are highlighted in the supplemental figures for this article. One sequence segment (ACGGGTCCGGACA) emerged 60 times in the anti-CCHF aptamer library, but nowhere else in the anti-arbovirus library and only a few other times in a larger library of aptamers known to bind bacteria and rickettsia or other targets. Diagnostic utility of some of the aptamers for arbovirus detection in lateral flow chromatographic assays and a fluorescent sandwich assay on the surface of magnetic microbeads is also demonstrated.
Conclusions
This article catalogues numerous DNA aptamer sequences which can bind various important pathogenic arboviruses and have, in some cases, already demonstrated diagnostic potential. These aptamer sequences are proprietary, patent-pending, and partially characterized. Therefore, they are offered to the scientific community for potential research use in diagnostic assays, biosensor applications or for possible passive immunity and prophylaxis against pathogenic viruses.
doi:10.1186/1756-0500-5-633
PMCID: PMC3517355
PMID: 23148669
Aptamer; Arbovirus; Consensus; DNA; Enzyme-linked; Fluorescence; Lateral flow; SELEX
Background
Ventricular septal rupture (VSR), a mechanical complication following an acute myocardial infarction (MI), is thought to result from coagulation necrosis due to lack of collateral reperfusion. Although the gold standard test to confirm left-to-right shunting between ventricular cavities remains invasive ventriculography, two-dimensional transthoracic echocardiography (TTE) with color flow Doppler and cardiac MRI (CMR) are reliable tests for the non-invasive diagnosis of VSR.
Case presentation
A 62-year-old Caucasian female presented with a late case of a VSR post inferior MI diagnosed by multimodality cardiac imaging including TTE, CMR and ventriculography.
Conclusion
We review the presentation, diagnosis and management of VSR post MI.
doi:10.1186/1756-0500-5-583
PMCID: PMC3505164
PMID: 23098382
Echocardiography; Cardiac Mri; Ventricular septal rupture
Background
The minimum age for the legal purchase of tobacco increased from 16 to 18 years in England, Scotland and Wales on 1 October 2007. The authors examined the impact of this legislation on disparities in smoking behaviour and access to cigarettes among youth in England.
Methods
A multivariate logistic regression analysis was carried out adjusting for secular trends in regular smoking using data from the Smoking, Drinking and Drug Use Survey, a national survey of 11e15 year olds. The primary outcome measure was regular smoking and the predictor variables were the law increasing the minimum age for purchase and eligibility for free school meals (FSM).
Results
Increasing the minimum age for purchase was associated with a significant reduction in regular smoking among youth (adjusted OR 0.67; 95% CI 0.55 to 0.81, p=0.0005). This effect was not significantly different in pupils eligible for FSM compared with those that were not (adjusted OR 1.29; 95% CI 0.95 to 1.76, p=0.10 for interaction term). The percentage of pupils who stated that they found it difficult to buy cigarettes from a shop did not increase in those eligible for FSM (25.2% to 33.3%; p=0.21) but did increase significantly in others (21.2% to 36.9%; p<0.01) between 2006 and 2008. No differences in ease of purchase were found between pupils eligible for FSM and those not before or after the legislation (2006: p=0.34, 2008: p=0.55).
Conclusions
Increasing the age for the legal purchase of tobacco was associated with reduced regular smoking among youth in England and appeared to have a similar impact in different socio-economic groups.
doi:10.1136/thx.2010.154963
PMCID: PMC3158837
PMID: 21502102
A new strategy to develop an effective vaccine is essential to control food-borne Salmonella enterica serovar Enteritidis infections. Bacterial ghosts (BGs), which are nonliving, Gram-negative bacterial cell envelopes, are generated by expulsion of the cytoplasmic contents from bacterial cells through controlled expression using the modified cI857/λ PR/gene E expression system. In the present study, the pJHL99 lysis plasmid carrying the mutated lambda pR37-cI857 repressor and PhiX174 lysis gene E was constructed and transformed in S. Enteritidis to produce a BG. Temperature induction of the lysis gene cassette at 42°C revealed quantitative killing of S. Enteritidis. The S. Enteritidis ghost was characterized using scanning and transmission electron microscopy to visualize the transmembrane tunnel structure and loss of cytoplasmic materials, respectively. The efficacy of the BG as a vaccine candidate was evaluated in a chicken model using 60 10-day-old chickens, which were divided into four groups (n = 15), A, B, C, and D. Group A was designated as the nonimmunized control group, whereas the birds in groups B, C, and D were immunized via the intramuscular, subcutaneous, and oral routes, respectively. The chickens from all immunized groups showed significant increases in plasma IgG and intestinal secretory IgA levels. The lymphocyte proliferation response and CD3+ CD4+ and CD3+ CD8+ T cell subpopulations were also significantly increased in all immunized groups. The data indicate that both humoral and cell-mediated immune responses are robustly stimulated. Based on an examination of the protection efficacy measured by observations of gross lesions in the organs and bacterial recovery, the candidate vaccine can provide efficient protection against virulent challenge.
doi:10.1128/IAI.06264-11
PMCID: PMC3318409
PMID: 22290147
Pancreatic encephalopathy refers to a gamut of neuropsychiatric symptoms complicating acute pancreatitis. Osmotic myelinolysis is a known complication of pancreatic encephalopathy. We evaluated a 58-year-old woman with pancreatic encephalopathy associated to pontine and extrapontine myelinolysis involving the brain and spinal cord. To our knowledge, this is the first clinic pathological case report of pancreatic encephalopathy involving the spinal cord.
doi:10.3389/fneur.2012.00135
PMCID: PMC3461402
PMID: 23060853
pancreatic encephalopathy; osmotic myelinolysis; extrapontine myelinolysis; pontine myelinolysis; leukoencephalopathy
The singular value decomposition deconvolution of cerebral tissue concentration-time (C-T) curves with the arterial input function (AIF) is commonly used in dynamic susceptibility contrast (DSC) cerebral perfusion MR imaging. However, it is sensitive to the time discrepancy between the arrival of the bolus in the tissue C-T curve and the AIF signal. This normally causes inaccuracy in the quantitative perfusion maps due to delay and dispersion effects. A comprehensive correction algorithm has been achieved through slice-dependent time-shifting of the AIF, and a delay-dependent dispersion correction model. The correction algorithm was tested in 11 healthy subjects and 3 ischemic stroke patients scanned with a quantitative perfusion pulse sequence at 1.5T. A validation study was performed on 5 patients with confirmed cerebrovascular occlusive disease scanned with MRI and positron emission tomography (PET) at 3.0T. A significant effect (p<0.05) was reported on the quantitative cerebral blood flow and mean transit time measurements (up to 50%). There was no statistically significant effect on the quantitative cerebral blood volume values. The in vivo results were in agreement with the simulation results, as well as previous literature. This minimizes the bias in patient diagnosis due to the existing errors and artifacts in DSC imaging.
doi:10.1002/mrm.23257
PMCID: PMC3310307
PMID: 22162092
Quantitative cerebral perfusion; arterial-tissue delay and dispersion; singular value decomposition; ischemic stroke
Chen, Chiu-Yu | Bertozzi, Cara | Zou, Zhiying | Yuan, Lijun | Lee, John S. | Lu, MinMin | Stachelek, Stan J. | Srinivasan, Sathish | Guo, Lili | Vicente, Andres | Mericko, Patricia | Levy, Robert J. | Makinen, Taija | Oliver, Guillermo | Kahn, Mark L.
doi:10.1172/JCI65314
PMCID: PMC3386843
Background
This article aims to demonstrate computational synthesis of Web-based experiments in undertaking experimentation on relationships among the participants' design preference, rationale, and cognitive test performance. The exemplified experiments were computationally synthesised, including the websites as materials, experiment protocols as methods, and cognitive tests as protocol modules. This work also exemplifies the use of a website synthesiser as an essential instrument enabling the participants to explore different possible designs, which were generated on the fly, before selection of preferred designs.
Methods
The participants were given interactive tree and table generators so that they could explore some different ways of presenting causality information in tables and trees as the visualisation formats. The participants gave their preference ratings for the available designs, as well as their rationale (criteria) for their design decisions. The participants were also asked to take four cognitive tests, which focus on the aspects of visualisation and analogy-making. The relationships among preference ratings, rationale, and the results of cognitive tests were analysed by conservative non-parametric statistics including Wilcoxon test, Krustal-Wallis test, and Kendall correlation.
Results
In the test, 41 of the total 64 participants preferred graphical (tree-form) to tabular presentation. Despite the popular preference for graphical presentation, the given tabular presentation was generally rated to be easier than graphical presentation to interpret, especially by those who were scored lower in the visualization and analogy-making tests.
Conclusions
This piece of evidence helps generate a hypothesis that design preferences are related to specific cognitive abilities. Without the use of computational synthesis, the experiment setup and scientific results would be impractical to obtain.
doi:10.1186/1759-4499-4-2
PMCID: PMC3386886
PMID: 22748000
Basu, Devraj | Montone, Kathleen T | Wang, Li-Ping | Gimotty, Phyllis A | Hammond, Rachel | Diehl, J Alan | Rustgi, Anil K | Lee, John T | Rasanen, Kati | Weinstein, Gregory S | Herlyn, Meenhard
Curative eradication of all cells within carcinomas is seldom achievable with chemotherapy alone. This limitation may be partially attributable to tumor cell subpopulations with intrinsic resistance to current drugs. Within squamous cell carcinoma (SCC) cell lines, we previously characterized a subpopulation of mesenchymal-like cells displaying phenotypic plasticity and increased resistance to both cytotoxic and targeted agents. These mesenchymal-like (Ecad-lo) cells are separable from epithelial-like (Ecad-hi) cells based on loss of surface E-cadherin and expression of vimentin. Despite their long-term plasticity, both Ecad-lo and Ecad-hi subsets in short-term culture maintained nearly uniform phenotypes after purification. This stability allowed testing of segregated subpopulations for relative sensitivity to the cytotoxic agent cisplatin in comparison to salinomycin, a compound with reported activity against CD44+CD24− stem-like cells in breast carcinomas. Salinomycin showed comparable efficacy against both Ecad-hi and Ecad-lo cells in contrast to cisplatin, which selectively depleted Ecad-hi cells. An in vivo correlate of these mesenchymal-like Ecad-lo cells was identified by immunohistochemical detection of vimentin-positive malignant subsets across a part of direct tumor xenografts (DTXs) of advanced stage SCC patient samples. Cisplatin treatment of mice with established DTXs caused enrichment of vimentin-positive malignant cells in residual tumors, but salinomycin depleted the same subpopulation. These results demonstrate that mesenchymal-like SCC cells, which resist current chemotherapies, respond to a treatment strategy developed against a stem-like subset in breast carcinoma. Further, they provide evidence of mesenchymal-like subsets being well-represented across advanced stage SCCs, suggesting that intrinsic drug resistance in this subpopulation has high clinical relevance.
doi:10.4161/cc.10.12.15883
PMCID: PMC3154419
PMID: 21558812
EMT; squamous cell carcinoma; head and neck cancer; esophageal cancer; chemotherapy resistance; salinomycin; tumor heterogeneity
Background
Type 2 diabetes mellitus is a major global public health problem in the worldwide and is increasing in aging populations. Magnesium intake may be one of the most important factors for diabetes prevention and management. Low magnesium intake may exacerbate metabolic abnormalities. In this study, the relationships of magnesium intake with metabolic parameters, depression and physical activity in elderly patients with type 2 diabetes were investigated.
Methods
This cross-sectional study involved 210 type 2 diabetes patients aged 65 years and above. Participants were interviewed to obtain information on lifestyle and 24-hour dietary recall. Assessment of depression was based on DSM-IV criteria. Clinical variables measured included anthropometric measurements, blood pressure, and biochemical determinations of blood and urine samples. Linear regression was applied to determine the relationships of magnesium intake with nutritional variables and metabolic parameters.
Results
Among all patients, 88.6% had magnesium intake which was less than the dietary reference intake, and 37.1% had hypomagnesaemia. Metabolic syndromes and depression were associated with lower magnesium intake (p < 0.05). A positive relationship was found between magnesium intake and HDL-cholesterol (p = 0.005). Magnesium intake was inversely correlated with triglyceride, waist circumference, body fat percent and body mass index (p < 0.005). After controlling confounding factor, HDL-cholesterol was significantly higher with increasing quartile of magnesium intake (p for trend = 0005). Waist circumference, body fat percentage, and body mass index were significantly lower with increase quartile of magnesium intake (p for trend < 0.001). The odds of depression, central obesity, high body fat percentage, and high body mass index were significantly lower with increasing quartile of magnesium intake (p for trend < 0.05). In addition, magnesium intake was related to high physical activity level and demonstrated lower serum magnesium levels. Serum magnesium was not significantly associated with metabolic parameters.
Conclusions
The majority of elderly type 2 diabetes who have low magnesium intake may compound this deficiency with metabolic abnormalities and depression. Future studies should determine the effects of increased magnesium intake or magnesium supplementation on metabolic control and depression in elderly people with type 2 diabetes.
doi:10.1186/1475-2891-11-41
PMCID: PMC3439347
PMID: 22695027
Magnesium; Diabetes; Metabolic control; Depression; Physical activity; Elderly
Chen, Chiu-Yu | Bertozzi, Cara | Zou, Zhiying | Yuan, Lijun | Lee, John S. | Lu, MinMin | Stachelek, Stan J. | Srinivasan, Sathish | Guo, Lili | Vincente, Andres | Mericko, Patricia | Levy, Robert J. | Makinen, Taija | Oliver, Guillermo | Kahn, Mark L.
Human vascular malformations cause disease as a result of changes in blood flow and vascular hemodynamic forces. Although the genetic mutations that underlie the formation of many human vascular malformations are known, the extent to which abnormal blood flow can subsequently influence the vascular genetic program and natural history is not. Loss of the SH2 domain–containing leukocyte protein of 76 kDa (SLP76) resulted in a vascular malformation that directed blood flow through mesenteric lymphatic vessels after birth in mice. Mesenteric vessels in the position of the congenital lymphatic in mature Slp76-null mice lacked lymphatic identity and expressed a marker of blood vessel identity. Genetic lineage tracing demonstrated that this change in vessel identity was the result of lymphatic endothelial cell reprogramming rather than replacement by blood endothelial cells. Exposure of lymphatic vessels to blood in the absence of significant flow did not alter vessel identity in vivo, but lymphatic endothelial cells exposed to similar levels of shear stress ex vivo rapidly lost expression of PROX1, a lymphatic fate–specifying transcription factor. These findings reveal that blood flow can convert lymphatic vessels to blood vessels, demonstrating that hemodynamic forces may reprogram endothelial and vessel identity in cardiovascular diseases associated with abnormal flow.
doi:10.1172/JCI57513
PMCID: PMC3366395
PMID: 22622036
doi:10.1186/1750-9378-7-S1-P35
PMCID: PMC3330109
Eight young children who displayed destructive behavior maintained, at least in part, by negative reinforcement received long-term functional communication training (FCT). During FCT, the children completed a portion of a task and then touched a communication card attached to a microswitch to obtain brief breaks. Prior to and intermittently throughout FCT, extinction probes were conducted within a withdrawal design in which task completion, manding, and destructive behavior were placed on extinction to evaluate the relative persistence of appropriate and destructive behavior over the course of treatment. FCT continued until appropriate behavior persisted and destructive behavior failed to recur at baseline levels during extinction probes. The completion of FCT was followed by four challenges to the persistence of treatment effects conducted within mixed- or multiple-schedule designs: (a) extended extinction sessions (from 5 to 15 min), (b) introduction of a novel task, (c) removal of the microswitch and communication card, and (d) a mixed schedule of reinforcement in which both appropriate and destructive behavior produced reinforcement. The results showed that although FCT often resulted in quick reductions in destructive behavior and increases in appropriate behavior, destructive behavior often recurred during the extinction probes conducted during the initial treatment. When the effects of treatment persisted during the extinction probes, the remaining challenges to treatment effects resulted in only mild to moderate disruptions in behavior. These results are consistent with the quantitative predictions of behavioral momentum theory and may provide an alternative definition of maintenance as constituting behavioral persistence.
doi:10.1901/jeab.2011.96-261
PMCID: PMC3168891
PMID: 21909168
functional communication training; behavioral persistence; behavioral momentum; destructive behavior; young children
Nderitu, Leonard | Lee, John S. | Omolo, Jared | Omulo, Sylvia | O'Guinn, Monica L. | Hightower, Allen | Mosha, Fausta | Mohamed, Mohamed | Munyua, Peninah | Nganga, Zipporah | Hiett, Kelli | Seal, Bruce | Feikin, Daniel R. | Breiman, Robert F. | Njenga, M. Kariuki
Background. During the Rift Valley fever (RVF) epidemic of 2006–2007 in eastern Africa, spatial mapping of the outbreaks across Kenya, Somalia, and Tanzania was performed and the RVF viruses were isolated and genetically characterized.
Methods. Following confirmation of the RVF epidemic in Kenya on 19 December 2006 and in Tanzania on 2 February 2007, teams were sent to the field for case finding. Human, livestock, and mosquito specimens were collected and viruses isolated. The World Health Organization response team in Kenya worked with the WHO’s polio surveillance team inside Somalia to collect information and specimens from Somalia.
Results. Seven geographical foci that reported hundreds of livestock and >25 cases in humans between December 2006 and June 2007 were identified. The onset of RVF cases in each epidemic focus was preceded by heavy rainfall and flooding for at least 10 days. Full-length genome analysis of 16 RVF virus isolates recovered from humans, livestock, and mosquitoes in 5 of the 7 outbreak foci revealed 3 distinct lineages of the viruses within and across outbreak foci.
Conclusion. The findings indicate that the sequential RVF epidemics in the region were caused by multiple lineages of the RVF virus, sometimes independently activated or introduced in distinct outbreak foci.
doi:10.1093/infdis/jiq004
PMCID: PMC3071275
PMID: 21282193
Diffuse Large B cell lymphomas (DLBCL) are the most prevalent of the non-Hodgkin lymphomas and are currently initially treated fairly successfully, but frequently relapse as refractory disease, resulting in poor salvage therapy options and short survival. The greatest challenge in improving survival of DLBCL patients is overcoming chemo-resistance, whose basis is poorly understood. Among the potential mediators of DLBCL chemo-resistance is the thioredxoin (Trx) family, primarily because Trx family members play critical roles in the regulation of cellular redox homeostasis, and recent studies have indicated that dysregulated redox homeostasis also plays a key role in chemoresistance. In this study, we showed that most of the DLBCL-derived cell lines and primary DLBCL cells express higher basal levels of Trx-1 than normal B cells and that Trx-1 expression level is associated with decreased patients survival. Our functional studies showed that inhibition of Trx-1 by small interfering RNA or a Trx-1 inhibitor (PX-12) inhibited DLBCL cell growth, clonogenicity, and also sensitized DLBCL cells to doxorubicin-induced cell growth inhibition in vitro. These results indicate that Trx-1 plays a key role in cell growth and survival, as well as chemoresistance, and is a potential target to overcome drug resistance in relapsed/refractory DLBCL.
PMCID: PMC3359887
PMID: 22447839
Trx-1; chemoresistance; DLBCL; cellular redox
Primary central nervous system (CNS) teratomas are rare tumors that consist of all three germ cell layers. We describe a young man with a primary malignant CNS teratocarcinoma presenting as leptomeningeal carcinomatosis. Diagnosis of primary CNS teratocarcinomas is challenging; relentless pursuit of the diagnosis must follow even if early ancillary studies are inconclusive.
doi:10.3389/fneur.2012.00014
PMCID: PMC3277263
PMID: 22363315
teratocarcinoma; leptomeningeal malignancy; central nervous system