Background and Purpose
The recording of fall events is usually subjective and imprecise, which limits clinical practice and falls-related research. We sought to develop and validate a scale to grade near-fall and fall events based on their severity represented by the use of healthcare resources, with the goal of standardizing fall reporting in the clinical and research settings.
Qualitative instrument development was based on a literature review and semi-structured interviews to assess face and content validity. We queried older individuals and healthcare professionals with expertise in the care of patients at risk of falling about clinically important differences to detect and how to optimize the scale's ease of use. To assess the scale's inter-rater reliability, we created 30 video-vignettes of falls and compared how healthcare professionals and volunteers rated each of the falls according to our grading scale.
We developed the illustrated 4-point Hopkins Falls Grading Scale (HFGS). The grades distinguish a near-fall (Grade 1) from a fall for which an individual did not receive medical attention (Grade 2), a fall associated with medical attention but not hospital admission (Grade 3), and a fall associated with hospital admission (Grade 4). Overall, the HFGS exhibited good face and content validity, and had an intraclass correlation coefficient of 0.998.
The 4-point HFGS demonstrates good face and content validity and high inter-rater reliability. We predict this tool will facilitate the standardization of falls reporting in both the clinical and research settings.
Falls definition; falls classification; falls reporting
Studies of Y chromosome evolution often emphasize gene loss, but this loss has been counterbalanced by addition of new genes. The DAZ genes, which are critical to human spermatogenesis, were acquired by the Y chromosome in the ancestor of Old World monkeys and apes. We and our colleagues recently sequenced the rhesus macaque Y chromosome, and comparison of this sequence to human and chimpanzee enables us to reconstruct much of the evolutionary history of DAZ. We report that DAZ arrived on the Y chromosome about 36 million years ago via the transposition of at least 1.1 megabases of autosomal DNA. This transposition also brought five additional genes to the Y chromosome, but all five genes were subsequently lost through mutation or deletion. As the only surviving gene, DAZ experienced extensive restructuring, including intragenic amplification and gene duplication, and has been the target of positive selection in the chimpanzee lineage.
Y chromosome; DAZ; rhesus macaque; chimpanzee; ampliconic
In this report, we conducted a secondary analysis of the Treatment of SSRI-Resistant Depression in Adolescents (TORDIA) study to explore the impact of specific cognitive–behavioral therapy (CBT) treatment components on outcome. In TORDIA, 334 youths (ages 12 to 18 years) with major depressive disorder who had failed to respond to an adequate course of selective serotonin reuptake inhibitor (SSRI) medication were randomized to a medication switch (either to an alternative SSRI or venlafaxine) with or without 12 weeks of adjunctive CBT. Participants who had more than 9 CBT sessions were 2.5 times more likely to have adequate treatment response than those who had 9 or fewer sessions. CBT participants who received problem-solving and social skills treatment components, controlling for number of sessions and other confounding variables, were 2.3 and 2.6 times, respectively, more likely to have a positive response. These preliminary findings underscore the importance of receiving an adequate number of sessions to attain an adequate clinical response. Finally, social skills and problem solving may be active elements in CBT for adolescent depression and should be considered in treatment by those working with seriously depressed youths.
cognitive–behavioral therapy; adolescent depression; treatment components
To characterize the physiologic nature of the vestibular dysfunction that occurs with the normative aging process.
Tertiary care academic medical center.
Fifty individuals age 70 and above.
Head thrust dynamic visual acuity testing (htDVA) and cervical and ocular vestibular-evoked myogenic potential (VEMP) testing.
Main Outcome Measures
Semicircular canal function measured by htDVA in each of the three semicircular canal planes, and saccular and utricular function measured by cVEMP and oVEMP testing, respectively.
We observed significant declines in semicircular canal function in each of the canal planes as well as otolith function associated with aging. We found that individuals with impaired horizontal and superior semicircular canal function were likely to also have concomitant deficits in utricular but not saccular function. Overall, we noted that the prevalence of semicircular canal dysfunction was highest followed by saccular then utricular impairment, although we did observe individuals with isolated otolith deficits.
These data suggest an overall decline in semicircular canal as well as otolith function associated with aging, although the magnitude of impairment was greater for the semicircular canals than the otoliths in this elderly population. A better understanding of the specific vestibular deficits that occur with aging can inform the development of rational screening, vestibular rehabilitation and fall risk reduction strategies in older individuals.
The human Y chromosome began to evolve from an autosome hundreds of millions of years ago, acquiring a sex-determining function and undergoing a series of inversions that suppressed crossing over with the X chromosome1,2. Little is known about the Y chromosome’s recent evolution because only the human Y chromosome has been fully sequenced. Prevailing theories hold that Y chromosomes evolve by gene loss, the pace of which slows over time, eventually leading to a paucity of genes, and stasis3,4. These theories have been buttressed by partial sequence data from newly emergent plant and animal Y chromosomes5-8, but they have not been tested in older, highly evolved Y chromosomes like that of humans. We therefore finished sequencing the male-specific region of the Y chromosome (MSY) in our closest living relative, the chimpanzee, achieving levels of accuracy and completion previously reached for the human MSY. We then compared the MSYs of the two species and found that they differ radically in sequence structure and gene content, implying rapid evolution during the past 6 million years. The chimpanzee MSY harbors twice as many massive palindromes as the human MSY, yet it has lost large fractions of the MSY protein-coding genes and gene families present in the last common ancestor. We suggest that the extraordinary divergence of the chimpanzee and human MSYs was driven by four synergistic factors: the MSY’s prominent role in sperm production, genetic hitchhiking effects in the absence of meiotic crossing over, frequent ectopic recombination within the MSY, and species differences in mating behavior. While genetic decay may be the principal dynamic in the evolution of newly emergent Y chromosomes, wholesale renovation is the paramount theme in the ongoing evolution of chimpanzee, human, and perhaps other older MSYs.
The cation independent mannose 6-phosphate/insulin-like growth factor 2 receptor (IGF2R) functions in the transportation and regulation of insulin-like growth factor 2 (IGF2) and mannose 6-phosphate modified proteins. The relative and specific titration of IGF2 by high affinity binding of IGF2R represents a mechanism that supports the parental conflict theory of genomic imprinting. Imprinting of Igf2 (paternal allele expressed) and Igf2r (maternal allele expressed) arose to regulate the relative supply of both proteins. Experiments in the mouse have established that loss of the maternal allele of Igf2r results in disproportionate growth and peri-natal lethality. In order to systematically investigate the consequences of loss of function and of hypomorphic alleles of Igf2r on growth functions, we introduced a conditional human IGF2R exon 3–48 cDNA into the intron 2 region of murine Igf2r. Here we show that the knock-in construct resulted in over-growth when the humanised Igf2r allele was maternally transmitted, a phenotype that was rescued by either paternal transmission of the humanised allele, expression of a wild-type paternal allele or loss of function of Igf2. We also show that expression of IGF2R protein was reduced to less than 50% overall in tissues previously known to be Igf2 growth dependent. This occurred despite the detection of mouse derived peptides, suggesting that trans-splicing of the knock-in human cDNA with the endogenous maternal mouse Igf2r allele. The phenotype following maternal transmission of the humanised allele resulted in overgrowth of the embryo, heart and placenta with partial peri-natal lethality, suggesting that further generation of hypomorphic Igf2r alleles are likely to be at the borderline of maintaining Igf2 dependent viability.
The human X and Y chromosomes evolved from an ordinary pair of autosomes during the past 200–300 million years1–3. Due to genetic decay, the human MSY (male-specific region of Y chromosome) retains only three percent of the ancestral autosomes’ genes4,5. This evolutionary decay was driven by a series of five “stratification” events. Each event suppressed X-Y crossing over within a chromosome segment or “stratum”, incorporated that segment into the MSY, and subjected its genes to the erosive forces that attend the absence of crossing over2,6. The last of these events occurred 30 million years ago (mya), or 5 million years before the human and Old World monkey (OWM) lineages diverged. Although speculation abounds regarding ongoing decay and looming extinction of the human Y chromosome7–10, remarkably little is known about how many MSY genes were lost in the human lineage in the 25 million years that have followed its separation from the OWM lineage. To explore this question, we sequenced the MSY of the rhesus macaque, an OWM, and compared it to the human MSY. We discovered that, during the last 25 million years, MSY gene loss in the human lineage was limited to the youngest stratum (stratum 5), which comprises three percent of the human MSY. Within the older strata, which collectively comprise the bulk of the human MSY, gene loss evidently ceased more than 25 mya. Likewise, the rhesus MSY has not lost any older genes (from strata 1–4) during the past 25 million years, despite major structural differences from the human MSY. The rhesus MSY is simpler, with few amplified gene families or palindromes that might enable intrachromosomal recombination and repair. We present an empirical reconstruction of human MSY evolution in which each stratum transitioned from rapid, exponential loss of ancestral genes to strict conservation through purifying selection.
Background: neopterin is a monocyte/macrophage-derived immune activation marker and its levels increase with age. Frailty is an important clinical syndrome of old age. Previous studies have shown significant association between elevated interleukin-6 (IL-6) levels and frailty. The objective of this study was to evaluate IL-6-independent association of serum neopterin levels with prevalent frailty.
Methods: this is a cross-sectional study in community-dwelling older adults recruited from residential and retirement communities in Baltimore, MD, USA. Frailty was determined using validated screening criteria. Serum neopterin and IL-6 levels were measured using standard enzyme-linked immunosorbent assay. Pearson correlation and multivariate linear regression analysis was performed to assess the relationship between log(neopterin) and log(IL-6). Odds ratios (ORs) for frailty were calculated using log(neopterin) and log(IL-6) as continuous measures and across tertiles of neopterin and IL-6 levels, adjusting for age, race, sex, education and body mass index.
Results: one hundred and thirty-three individuals with a mean age of 84 years (range 72–97) completed the study. Neopterin levels were significantly higher in frail older adults than those in non-frail controls [median: 8.94 versus 8.35 nM, respectively, P < 0.001 t-test on log(neopterin)]. Log(neopterin) was significantly associated with prevalent frailty, adjusting for log(IL-6). Participants in the top tertile of neopterin had OR of 3.80 [95% confidence interval (CI) = 1.36–10.6, P < 0.01] for frailty. As expected, participants in the top tertile of IL-6 had OR of 3.29 (95% CI = 1.21–7.86, P < 0.05) for frailty. Log(neopterin) correlated with log(IL-6) (correlation coefficient = 0.19, P < 0.05). Moreover, OR for participants in the top neopterin tertile remained significant after adjusting for IL-6 (OR = 3.97, 95% CI = 1.15–13.72, P < 0.05).
Conclusion: elevated neopterin levels had IL-6-independent association with prevalent frailty, suggesting potential monocyte/macrophage-mediated immune activation in the frail elderly.
frailty; neopterin; monocyte/macrophage-mediated immune activation; IL-6; elderly
Preclinical and correlative studies suggest reduced breast cancer with higher lignan intake or blood levels. We conducted a pilot study of modulation of risk biomarkers for breast cancer in premenopausal women after administration of the plant lignan secoisolariciresinol given as the diglycoside (SDG). Eligibility criteria included regular menstrual cycles, no oral contraceptives, a greater than 3-fold increase in 5 year risk, and baseline Ki-67 ≥2% in areas of hyperplasia in breast tissue sampled by random periareolar fine needle aspiration (RPFNA) during the follicular phase of the menstrual cycle. SDG 50 mg daily was given for 12 months, followed by repeat RPFNA. The primary endpoint was change in Ki-67. Secondary endpoints included change in cytomorphology, mammographic breast density, serum bioavailable estradiol, and testosterone IGF-I and IGFBP-3, and plasma lignan levels. Forty-five of 49 eligible women completed the study with excellent compliance (median = 96%) and few serious side effects (4% grade 3). Median plasma enterolactone increased ~ 9-fold, and total lignans 16 fold. Thirty-six (80%) of the 45 evaluable subjects demonstrated a decrease in Ki-67, from a median of 4% (range 2–16.8 %) to 2% (range 0–15.2%) (p<0.001 by Wilcoxon signed rank test). A decrease from baseline in the proportion of women with atypical cytology (p=0.035) was also observed. Based on favorable risk biomarker modulation and lack of adverse events, we are initiating a randomized trial of SDG vs. placebo in premenopausal women.
To determine whether obesity and premature adrenarche are additive events increasing the risk of insulin resistance and β-cell failure, using early insulin response (EIR) or the insulinogenic index and proinsulin as markers.
Prospective case-control study at a tertiary care academic medical center; 81 prepubertal, predominantly Hispanic children (34 M/47 F): Lean Control [(4M, 6F) age(y), 6.5±1.2; BMI-z, 0.08±0.6], Obese Control [(20M, 10F) age(y), 7.2±1.5; BMI-z, 2.5±0.5], lean premature adrenarche [(3M, 11F) age(y), 7.1±1.2; BMI-z, 0.09±0.6], and obese premature adrenarche [(7M, 20F) age(y), 7.3±1.0; BMI-z, 2.2±0.4]. Fasting glucose (G0), insulin (I0), PI0, androgen levels, IGF-1, IGFBP-1, and lipids were obtained. OGTT was performed. EIR was calculated as (I30 – I0)/(G30 – G0). Between group differences were assessed with two-way analysis of variance with interactions and associations explored with correlation/regression.
EIR was greater in all obese patients with and without premature adrenarche. Combined analysis of the independent variables, obesity and premature adrenarche, showed that obese premature adrenarche had the greatest EIR. Obese subjects with premature adrenarche had greater fasting PI levels than their lean counterparts. Fasting PI/I ratio showed no statistical significance between groups.
We have used EIR and PI as markers to assess risk of insulin resistance and impaired insulin secretion, and have shown that obese children with premature adrenarche may be at greater risk for the development of pre-diabetes and T2DM than their lean counterparts.
Pre-diabetes; Insulinogenic index; Overweight children
To describe the elements of a manualized cognitive behavior psychotherapy for suicide prevention (CBT-SP) and to report its feasibility in preventing the recurrence of suicidal behavior in adolescents who have recently attempted suicide.
CBT-SP was developed using a risk reduction, relapse prevention approach and theoretically grounded in principles of cognitive behavior therapy, dialectical behavioral therapy and targeted therapies for suicidal, depressed youth. CBT-SP consists of acute and continuation phases, each lasting about 12 sessions, and includes a chain analysis of the suicidal event, safety plan development, skill building, psychoeducation, family intervention, and relapse prevention.
CBT-SP was administered to 110 depressed, recent suicide attempters aged 13–19 years (mean 15.8±1.6) across five academic sites. Twelve or more sessions were completed by 72.4% of the sample.
A specific intervention for adolescents at high risk for repeated suicide attempts has been developed and manualized, and further testing of its efficacy appears feasible.
Suicide; psychotherapy; depression; adolescents
To identify the predictors of suicidal events and attempts in depressed adolescent suicide attempters treated in an open treatment trial.
Adolescents who had made a recent suicide attempt and had unipolar depression (n=124) were either randomized (n=22) or given a choice (n=102) among three conditions. Two participants withdrew prior to treatment assignment. The remaining 124 youth received either: a specialized psychotherapy for suicide attempting adolescents (n=17), a medication algorithm (n=14), or the combination (n=93). The participants were followed up 6 months after intake with respect to rate, timing, and predictors of a suicidal event (attempt or acute suicidal ideation necessitating emergency referral).
The morbid risks of suicidal events and attempts upon 6-month follow-up were 0.19 and 0.12, respectively, with a median time to event of 44 days. Higher self-rated depression, suicidal ideation, family income, greater number of previous suicide attempts, lower maximum lethality of previous attempt, history of sexual abuse, and lower family cohesion predicted the occurrence, and earlier time to event, with similar findings for the outcome of attempts. A slower decline in suicidal ideation was associated with the occurrence of a suicidal event.
In this open trial, the 6-month morbid risks for suicidal events and for re-attempts were lower than in other comparable samples, suggesting that this intervention should be studied further. Important treatment targets include suicidal ideation, family cohesion, and sequelae of previous abuse. Because 40% of events occurred with 4 weeks of intake, an emphasis on safety planning and increased therapeutic contact early in treatment may be warranted.
suicide attempt; adolescents; depression; pharmacotherapy; psychotherapy
Relapse rates for children and adolescents with major depressive disorder (MDD) range from 30% to 40% within 1 to 2 years after acute treatment. Although relapse rates are high, there have been relatively few studies on the prevention of relapse in youth. While acute phase pharmacotherapy has been shown to reduce symptoms rapidly in depressed youth, children and adolescents frequently report ongoing residual symptoms and often relapse following acute treatment. Recent adult trials have begun examining augmentation with psychosocial treatment after successful medication treatment to enhance medication response and prevent future relapse. This strategy has not yet been examined in youth with depression. Here we present initial efforts to develop a sequential, combination treatment strategy to promoting rapid remission and to prevent relapse in depressed youth. We describe efforts to adapt CBT to prevent relapse (RP-CBT) in youth who respond to pharmacotherapy. The goals of RP-CBT include: preventing relapse, increasing wellness, and developing skills to promote and sustain a healthy emotional lifestyle. We describe the rationale for, components of, and methods used to develop RP-CBT. The results from a small open series sample demonstrate feasibility and indicate that youth appear to tolerate RP-CBT well. A future test of the treatment in a randomized controlled trial is described.
We examine remission rate probabilities, recovery rates, and residual symptoms across 36 weeks in the Treatment for Adolescents with Depression Study (TADS).
TADS, a multisite clinical trial, randomized 439 adolescents with major depressive disorder (MDD) to 12 weeks of treatment to fluoxetine (FLX), cognitive behavioral therapy (CBT), their combination (COMB), or pill placebo (PBO). The PBO group, treated openly after week 12, was not included in the subsequent analyses. Treatment differences in remission rates and probabilities of remission over time are compared. Recovery rates in remitters at week 12 (acute phase remitters) and week 18 (continuation phase remitters) are summarized. We also examined whether residual symptoms at the end of 12 weeks of acute treatment predicted later remission.
At Week 36, the estimated remission rates for intention-to-treat cases were: COMB: 60%, FLX: 55%; CBT: 64%; overall: 60%. Paired comparisons reveal that at week 24 all active treatments converge on remission outcomes. The recovery rate at Week 36 was 65% for acute phase remitters and 71% for continuation phase remitters, with no significant between-treatment differences in recovery rates. Residual symptoms at the end of acute treatment predicted failure to achieve remission at weeks 18 and 36.
The majority of depressed adolescents in all three treatment modalities achieved remission at the end of nine months of treatment.
adolescent depression; remission; residual symptoms; recovery
We present results of a feasibility test of a sequential treatment strategy using continuation phase cognitive-behavioral therapy (CBT) to prevent relapse in youths with major depressive disorder (MDD) who have responded to acute phase pharmacotherapy.
Forty-six youths (ages 11–18 years) who had responded to 12 weeks of treatment with fluoxetine were randomized to receive either 6 months of continued antidepressant medication management (MM) or antidepressant MM plus relapse prevention CBT (MM+CBT). Primary outcome was time to relapse, defined as a Childhood Depression Rating Scale-Revised score of 40 or higher and 2 weeks of symptom worsening or clinical deterioration warranting alteration of treatment to prevent full relapse.
Cox proportional hazards regression, adjusting for depression severity at randomization and for the hazard of relapsing by age across the trial, revealed that participants in the MM treatment group had a significantly greater risk for relapse than those in the MM+CBT treatment group (hazard ratio = 8.80; 95% confidence interval 1.01–76.89; χ2 = 3.86, p = .049) during 6 months of continuation treatment. In addition, patient satisfaction was significantly higher in the MM+CBT group. No differences were found between the two treatment groups on attrition rate, serious adverse events, and overall global functioning.
These preliminary results suggest that continuation phase CBT reduces the risk for relapse by eightfold compared with pharmacotherapy responders who received antidepressant medication alone during the 6-month continuation phase.
depression; CBT; relapse prevention; sequential treatment
In the present study, we assess maternal depressive symptoms at the beginning and end of treatment to investigate the possible reciprocal relationship of maternal illness with the child’s depressive illness and treatment.
We present data on 146 children and their mothers who were participating in a pediatric acute treatment study of fluoxetine. Patients were assessed with the Children’s Depression Rating Scale-Revised at baseline and at each treatment visit. Mothers completed the Quick Inventory of Depressive Symptomatology-Self Report at baseline and end of acute treatment.
Thirty percent of mothers had moderate to severe levels of depressive symptoms at the child’s baseline assessment. Overall, mothers reported improvement in maternal depressive symptoms at the end of their child’s acute treatment, although maternal depression was not specifically targeted for intervention. Furthermore, mother’s depressive symptoms appear to be associated with the child’s depression severity both at the beginning and end of treatment. Mothers with higher levels of depressive symptoms had children with higher levels of depression severity at baseline and over the course of treatment. However, maternal depressive symptoms at baseline had no association with the rate of improvement of child depression severity.
This study indicates a positive relationship between the depression severity of mothers and their children. These findings highlight potential areas of intervention in the acute treatment of childhood depression.
maternal depressive symptoms; pediatric depression; acute treatment of pediatric depression
The authors examined whether initial assignment to receive placebo for 12 weeks followed by open active treatment as clinically indicated was associated with different levels of benefit and risk of harm across 36 weeks as compared with initial assignment to receive active treatments.
Adolescents with major depressive disorder (N=439) were randomly assigned to receive an initial 12 weeks of treatment with fluoxetine, cognitive-behavioral therapy (CBT), combination treatment with fluoxetine and CBT, or clinical management with placebo; those assigned to placebo received open active treatment as clinically indicated after 12 weeks of placebo. Assessments were conducted every 6 weeks for 36 weeks. The primary outcome measures were response and remission based on scores on the Children’s Depression Rating Scale–Revised and the Clinical Global Impression improvement subscale.
At week 36, the response rate was 82% in the placebo/open group and 83% in the active treatment groups. The remission rate was 48% in the placebo/open group and 59% in the active treatment groups, a difference that approached statistical significance. Patients who responded to placebo generally retained their response. Those who did not respond to placebo subsequently responded to active treatment at the same rate as those initially assigned to active treatments. There were no differences between groups in rates of suicidal events, study retention, or symptom worsening.
Remission rates at 9 months were lower in patients treated initially with placebo, but 3 months of placebo treatment was not associated with any harm or diminished response to subsequent treatment.
Production of interleukin-10 (IL-10) by C57BL/6 mice following infection with Borrelia burgdorferi has been proposed as a mechanism whereby resistance to the development of experimental Lyme arthritis is maintained. In the current study, we sought to determine the role of IL-10 during infection of arthritis- and carditis-susceptible C3H mice. Infection of C3H IL-10−/− mice led to increased joint swelling and arthritis severity scores over those of wild-type C3H mice. Measurement of B. burgdorferi numbers in joints or disseminated tissues indicated a more efficient clearance of spirochetes in the absence of IL-10, similar to that reported in C57BL/6 IL-10−/− mice. However, in contrast to previous in vitro work, infection of C3H IL-10−/− mice led to decreased in vivo expression of the cytokines KC, IL-1β, IL-4, and IL-12p70 in the infected joints. Finally, adenoviral expression of IL-10 in the infected joints of C3H mice was unable to modulate the development of severe Lyme arthritis and had no effect on spirochete clearance or Borrelia-specific antibody production. Development of Lyme carditis appeared to be independent of modulation by IL-10. These results suggest that IL-10 limits the development of joint inflammation in both arthritis-resistant and -susceptible mouse strains infected with B. burgdorferi and that increased IL-10 production cannot rescue genetic susceptibility to development of pathology in this model.
Immunotherapeutics designed to dissolve existing amyloid plaques or to interrupt amyloid-beta (Aβ) accumulation may be feasible for treatment and/or prevention of Alzheimer’s disease (AD). “Shaping” immune responses elicited against Aβ is requisite to generate an efficacious and safe outcome by minimizing the possibility of deleterious inflammatory reactions in the brain as observed in clinical testing of Aβ peptide/adjuvant-based modalities. Herpes Simplex Virus (HSV)-based amplicons can co-express multiple antigens and/or immunomodulatory genes due to their large genetic size capacity, thereby facilitating antigen-specific immune response shaping. We have constructed an amplicon (HSVIEAβCMVIL-4) that co-delivers Aβ1-42 with interleukin-4, a cytokine that promotes the generation of Th2-like T cell responses, which are favored in the setting of AD immunotherapy. Triple-transgenic AD (3xTg-AD) mice, which progressively develop both amyloid and neurofibrillary tangle pathology, were vaccinated thrice with HSVIEAβCMVIL-4, or a set of control amplicon vectors. Increased Th2-related, Aβ-specific antibodies, improved learning and memory functioning, and prevention of AD-related amyloid and tau pathological progression were observed in HSVIEAβCMVIL-4 vaccinated mice as compared to the other experimental groups. Our study underscores the potential of Aβ immunotherapy for AD and highlights the potency of amplicons to facilitate immune response modulation to a disease-relevant antigen.
Alzheimer’s disease; behavior; Barnes maze; Aβ deposition; Tau; triple-transgenic mice
Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) stimulates proliferation of hematopoietic cells of the macrophage and granulocyte lineages and is used clinically to treat neutropenia and other myeloid disorders. Because of its short circulating half-life GM-CSF is administered to patients by daily injection. We describe here the engineering of highly potent, long acting human GM-CSF proteins through site-specific modification of GM-CSF cysteine analogs with a cysteine-reactive polyethylene glycol (PEG) reagent. Thirteen cysteine analogs of GM-CSF were constructed, primarily in non-helical regions of the protein believed to lie away from the major receptor binding sites. The GM-CSF cysteine analogs were properly processed, but insoluble following secretion into the Escherichia coli periplasm. The proteins were refolded and purified by column chromatography. Ten of the cysteine analogs could be modified with a 5 kDa-maleimide PEG and seven of the mono-PEGylated proteins were purified by ion-exchange column chromatography. Biological activities of the 13 cysteine analogs and seven PEGylated cysteine analogs were comparable to that of wild type GM-CSF in an in vitro cell proliferation assay using human TF-1 cells. One cysteine analog was modified with larger 10 kDa-, 20 kDa- and 40 kDa-PEGs, with only minimal loss of in vitro bioactivity. Pharmacokinetic experiments in rats demonstrated that the PEGylated proteins had up to 47-fold longer circulating half-lives than wild type GM-CSF. These data demonstrate the utility of site-specific PEGylation for creating highly potent, long-acting GM-CSF analogs, and provide further evidence that the non-helical regions of human GM-CSF examined are largely non-essential for biological activity of the protein.
During clinical training, house officers frequently encounter intense experiences that may affect their personal growth. The purpose of this study was to explore processes related to personal growth during internship.
Prospective qualitative study conducted over the course of internship.
Thirty-two postgraduate year (PGY)-1 residents from 9 U.S. internal medicine training programs.
Every 8 weeks, interns responded by e-mail to an open-ended question related to personal growth. Content analysis methods were used to analyze the interns' writings to identify triggers, facilitators, and barriers related to personal growth.
Triggers for personal growth included caring for critically ill or dying patients, receiving feedback, witnessing unprofessional behavior, experiencing personal problems, and dealing with the increased responsibility of internship. Facilitators of personal growth included supportive relationships, reflection, and commitment to core values. Fatigue, lack of personal time, and overwhelming work were barriers to personal growth. The balance between facilitators and barriers may dictate the extent to which personal growth occurs.
Efforts to support personal growth during residency training include fostering supportive relationships, encouraging reflection, and recognizing interns' core values especially in association with powerful triggers.
graduate medical education; personal growth; qualitative research
Seventy-two consecutive patients treated with electroconvulsive therapy (ECT) for severe mental illness were asked their opinions about ECT: 83% considered they had improved as a result of the treatment and 81% would have it again. Most found the experience neutral or pleasant and 54% thought the dentist more distressing. Claims in newspapers, magazines, television and elsewhere that ECT is cruel and frightening receive little support from the results of this study.