An In Vitro Model of Latency and Reactivation of Varicella Zoster Virus in Human Stem Cell-Derived Neurons

Varicella zoster virus (VZV) latency in sensory and autonomic neurons has remained enigmatic and difficult to study, and experimental reactivation has not yet been achieved. We have previously shown that human embryonic stem cell (hESC)-derived neurons are permissive to a productive and spreading VZV infection. We now demonstrate that hESC-derived neurons can also host a persistent non-productive infection lasting for weeks which can subsequently be reactivated by multiple experimental stimuli. Quiescent infections were established by exposing neurons to low titer cell-free VZV either by using acyclovir or by infection of axons in compartmented microfluidic chambers without acyclovir. VZV DNA and low levels of viral transcription were detectable by qPCR for up to seven weeks. Quiescently-infected human neuronal cultures were induced to undergo renewed viral gene and protein expression by growth factor removal or by inhibition of PI3-Kinase activity. Strikingly, incubation of cultures induced to reactivate at a lower temperature (34°C) resulted in enhanced VZV reactivation, resulting in spreading, productive infections. Comparison of VZV genome transcription in quiescently-infected to productively-infected neurons using RNASeq revealed preferential transcription from specific genome regions, especially the duplicated regions. These experiments establish a powerful new system for modeling the VZV latent state, and reveal a potential role for temperature in VZV reactivation and disease

Restoration of energy homeostasis by SIRT6 extends healthy lifespan

Aging leads to a gradual decline in physical activity and disrupted energy homeostasis. The NAD+-dependent SIRT6 deacylase regulates aging and metabolism through mechanisms that largely remain unknown. Here, we show that SIRT6 overexpression leads to a reduction in frailty and lifespan extension in both male and female B6 mice. A combination of physiological assays, in vivo multi-omics analyses and 13C lactate tracing identified an age-dependent decline in glucose homeostasis and hepatic glucose output in wild type mice. In contrast, aged SIRT6-transgenic mice preserve hepatic glucose output and glucose homeostasis through an improvement in the utilization of two major gluconeogenic precursors, lactate and glycerol. To mediate these changes, mechanistically, SIRT6 increases hepatic gluconeogenic gene expression, de novo NAD+ synthesis, and systemically enhances glycerol release from adipose tissue. These findings show that SIRT6 optimizes energy homeostasis in old age to delay frailty and preserve healthy aging

Induction Therapy for Locally Advanced, Resectable Esophagogastric Cancer: A Phase I Trial of Vandetanib (ZD6474), Paclitaxel, Carboplatin, 5-Fluorouracil, and Radiotherapy Followed by Resection

Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.OBJECTIVES:: Preoperative chemotherapy and radiation for localized esophageal cancer produces cure rates near 30% when combined with surgical resection. Vandetanib, a small molecule receptor tyrosine kinase inhibitor of VEGFR-2, VEGFR-3, RET, and EGFR, demonstrated synergy with radiation and chemotherapy in preclinical models. We conducted a phase I study to assess the safety and tolerability of vandetanib when combined with preoperative chemoradiation in patients with localized esophageal carcinoma who were surgical candidates. METHODS:: Patients with stage II-III esophageal and gastroesophageal junction carcinoma without prior therapy were enrolled in a 3+3 phase I design. Patients received once-daily vandetanib (planned dosing levels of 100, 200, and 300 mg) with concomitant daily radiotherapy (1.8 Gy/d, 45 Gy total) and chemotherapy, consisting of infusional 5-FU (225 mg/m/d over 96 h, weekly), paclitaxel (50 mg/m, days 1, 8, 15, 22, 29) and carboplatin (AUC of 5, days 1, 29). RESULTS:: A total 9 patients were enrolled with 8 having either distal esophageal or gastroesophageal junction carcinomas. All patients completed the planned preoperative chemoradiation and underwent esophagectomy. Nausea (44%) and anorexia (44%) were the most common acute toxicities of any grade. One grade 4 nonhematologic toxicity was observed (gastrobronchial fistula). One additional patient suffered a late complication, a fatal aortoenteric hemorrhage, not definitively related to the investigational regimen. Five (56%) patients achieved a pathologic complete response. Three (33%) additional patients had only microscopic residual disease. Five (56%) patients remain alive and disease free with a median follow-up of 3.7 years and median overall survival of 3.2 years. The maximum tolerated dose was vandetanib 100 mg/d. CONCLUSIONS:: Vandetanib at 100 mg daily is tolerable in combination with preoperative chemotherapy (5-FU, paclitaxel, carboplatin) and radiation therapy with encouraging efficacy worthy of future study

Induction Therapy for Locally Advanced, Resectable Esophagogastric Cancer

© 2017 Wolters Kluwer Health, Inc. Preoperative chemotherapy and radiation for localized esophageal cancer produces cure rates near 30% when combined with surgical resection. Vandetanib, a small molecule receptor tyrosine kinase inhibitor of VEGFR-2, VEGFR-3, RET, and EGFR, demonstrated synergy with radiation and chemotherapy in preclinical models. We conducted a phase I study to assess the safety and tolerability of vandetanib when combined with preoperative chemoradiation in patients with localized esophageal carcinoma who were surgical candidates. Methods: Patients with stage II-III esophageal and gastroesophageal junction carcinoma without prior therapy were enrolled in a 3+3 phase I design. Patients received once-daily vandetanib (planned dosing levels of 100, 200, and 300 mg) with concomitant daily radiotherapy (1.8 Gy/d, 45 Gy total) and chemotherapy, consisting of infusional 5-FU (225 mg/m 2/d over 96 h, weekly), paclitaxel (50 mg/m 2, days 1, 8, 15, 22, 29) and carboplatin (AUC of 5, days 1, 29). Results: A total 9 patients were enrolled with 8 having either distal esophageal or gastroesophageal junction carcinomas. All patients completed the planned preoperative chemoradiation and underwent esophagectomy. Nausea (44%) and anorexia (44%) were the most common acute toxicities of any grade. One grade 4 nonhematologic toxicity was observed (gastrobronchial fistula). One additional patient suffered a late complication, a fatal aortoenteric hemorrhage, not definitively related to the investigational regimen. Five (56%) patients achieved a pathologic complete response. Three (33%) additional patients had only microscopic residual disease. Five (56%) patients remain alive and disease free with a median follow-up of 3.7 years and median overall survival of 3.2 years. The maximum tolerated dose was vandetanib 100 mg/d. Conclusions: Vandetanib at 100 mg daily is tolerable in combination with preoperative chemotherapy (5-FU, paclitaxel, carboplatin) and radiation therapy with encouraging efficacy worthy of future study

An Eight-Week Trial Investigating the Efficacy and Tolerability of Atorvastatin for Children and Adolescents With Heterozygous Familial Hypercholesterolemia

This study aimed to assess the efficacy and tolerability of atorvastatin in Tanner stage (TS) 1 patients ages 6 to 10 years and TS ≥2 patients ages 10 to <18 years with genetically confirmed heterozygous familial hypercholesterolemia (HeFH) and a low density lipoprotein cholesterol (LDL-C) level of 4 mmol/l (155 mg/dl) or higher. In this open-label, 8-week study, 15 TS 1 children were treated initially with atorvastatin 5 mg/day and 24 TS ≥2 children with 10 mg/day. Doses were doubled at week 4 if the LDL-C target (<3.35 mmol/l [130 mg/dl]) was not achieved. The efficacy variables were the percentage change from baseline in LDL-C, total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), very low density lipoprotein cholesterol (VLDL-C), and apolipoprotein (Apo) A-I and Apo B. Safety evaluations included clinical monitoring, subject-reported adverse events (AEs), vital signs, and clinical laboratory tests. The mean values for LDL-C, TC, VLDL-C, and Apo B decreased by week 2 among all TS 1 and TS ≥2 patients, whereas TG, HDL-C, and Apo A-I varied considerably from week to week. After 8 weeks, the mean reduction in LDL-C was −40.7% ± 8.4 for the TS 1 children and −39.7% ± 10.3 for the TS ≥2 children. For the TS 1 patients, the mean reductions were −34.1% ± 6.9 for TC and −6.0% ± 32.1 for TG. The corresponding changes for the TS ≥2 patients were −35.6% ± 9.5 for TC and −21.1% ± 29.7 for TG. Four patients experienced mild to moderate treatment-related AEs. No serious AEs or discontinuations were reported. Overall, no difference in safety or tolerability was observed between the younger and older cohorts. Across the range of exposures after atorvastatin 5 to 10 mg (TS 1) or atorvastatin 10 to 20 mg (TS ≥2) doses for 8 weeks, clinically meaningful reductions in LDL-C, TC, VLDL-C, and Apo were observed with atorvastatin in pediatric patients who had HeFH. Atorvastatin also was well tolerated in this population

Mistreatment of university students most common during medical studies

BACKGROUND: This study concerns the occurrence of various forms of mistreatment by staff and fellow students experienced by students in the Faculty of Medicine and the other four faculties of the University of Oulu, Finland. METHODS: A questionnaire with 51 questions on various forms of physical and psychological mistreatment was distributed to 665 students (451 females) after lectures or examinations and filled in and returned. The results were analysed by gender and faculty. The differences between the males and females were assessed statistically using a test for the equality of two proportions. An exact two-sided P value was calculated using a mid-P approach to Fisher's exact test (the null hypothesis being that there is no difference between the two proportions). RESULTS: About half of the students answering the questionnaire had experienced some form of mistreatment by staff during their university studies, most commonly humiliation and contempt (40%), negative or disparaging remarks (34%), yelling and shouting (23%), sexual harassment and other forms of gender-based mistreatment (17%) and tasks assigned as punishment (13%). The students in the Faculty of Medicine reported every form of mistreatment more commonly than those in the Faculties of Humanities, Education, Science and Technology. Experiences of mistreatment varied, but clear messages regarding its patterns were to be found in each faculty. Female students reported more instances of mistreatment than males and were more disturbed by them. Professors, lecturers and other staff in particular mistreated female students more than they mistreated males. About half of the respondents reported some form of mistreatment by their fellow students. CONCLUSION: Students in the Faculty of Medicine reported the greatest amount of mistreatment. If a faculty mistreats its students, its success in the main tasks of universities, research, teaching and learning, will be threatened. The results challenge university teachers, especially in faculties of medicine, to evaluate their ability to create a safe environment conducive to learning

Family medicine graduates' perceptions of intimidation, harassment, and discrimination during residency training

<p>Abstract</p> <p>Background</p> <p>Despite there being considerable literature documenting learner distress and perceptions of mistreatment in medical education settings, these concerns have not been explored in-depth in Canadian family medicine residency programs. The purpose of the study was to examine intimidation, harassment and/or discrimination (IHD) as reported by Alberta family medicine graduates during their two-year residency program.</p> <p>Methods</p> <p>A retrospective questionnaire survey was conducted of all (n = 377) family medicine graduates from the University of Alberta and University of Calgary who completed residency training during 2001-2005. The frequency, type, source, and perceived basis of IHD were examined by gender, age, and Canadian vs international medical graduate. Descriptive data analysis (frequency, crosstabs), Chi-square, Fisher's Exact test, analysis of variance, and logistic regression were used as appropriate.</p> <p>Results</p> <p>Of 377 graduates, 242 (64.2%) responded to the survey, with 44.7% reporting they had experienced IHD while a resident. The most frequent type of IHD experienced was in the form of inappropriate verbal comments (94.3%), followed by work as punishment (27.6%). The main sources of IHD were specialist physicians (77.1%), hospital nurses (54.3%), specialty residents (45.7%), and patients (35.2%). The primary basis for IHD was perceived to be gender (26.7%), followed by ethnicity (16.2%), and culture (9.5%). A significantly greater proportion of males (38.6%) than females (20.0%) experienced IHD in the form of work as punishment. While a similar proportion of Canadian (46.1%) and international medical graduates (IMGs) (41.0%) experienced IHD, a significantly greater proportion of IMGs perceived ethnicity, culture, or language to be the basis of IHD.</p> <p>Conclusions</p> <p>Perceptions of IHD are prevalent among family medicine graduates. Residency programs should explicitly recognize and robustly address all IHD concerns.</p

Prevalence of Mistreatment or Belittlement among Medical Students – A Cross Sectional Survey at a Private Medical School in Karachi, Pakistan

Background: Mistreatment or belittlement of medical students either by faculty or fellow students has often been reported. Perception of mistreatment has also been associated with increased degree of psychological morbidity. There is a lack of such studies being conducted amongst the medical students of Pakistan. The aim of this study was to determine the prevalence and forms of perceived mistreatment and presence of mental health morbidity in a private medical school in Pakistan. Also, any association between mental health morbidity and mistreatment was to be identified. Methods: A cross sectional study was carried out on medical students from Aga Khan University Hospital, Karachi, Pakistan during the period of June-September 2007. A self administered questionnaire, adapted from Frank et al and Baldwin et al was distributed to a total of 350 students. The questionnaire consisted of three parts: the first dealing with the demographics of the population, the second concerning the various forms of mistreatment, while the third assessed the mental health of students using the General Health Questionnaire 12(GHQ12). Descriptive statistics were performed. The Chi-square test and Fisher\u27s exact tests were applied. Results: A total of 350 students were approached out of which 232 completed the questionnaire giving a response rate of 66.2%. Mistreatment was reported by 62.5% (145/232) of the respondents. Of these, 69.7% (83/145) were males and 54.9% (62/145) were females. There was a significant relationship between gender, year division, stress at medical school and possible use of drugs/alcohol and reported mistreatment but no statistical relationship was seen with psychiatric morbidity. The overall prevalence of psychological morbidity was 34.8% (77/221). Conclusion: This study suggests high prevalence of perceived mistreatment and psychological morbidity among Pakistani medical students. However, no association was found between these two aspects of medical student education. There is a need to bring about changes to make the medical education environment conducive to learning. Increased student feedback, support systems and guidance about progress throughout the year and the provision of adequate learning resources may provide help with resolving both of these issues

Unexpected High Digestion Rate of Cooked Starch by the Ct-Maltase-Glucoamylase Small Intestine Mucosal α-Glucosidase Subunit

For starch digestion to glucose, two luminal α-amylases and four gut mucosal α-glucosidase subunits are employed. The aim of this research was to investigate, for the first time, direct digestion capability of individual mucosal α-glucosidases on cooked (gelatinized) starch. Gelatinized normal maize starch was digested with N- and C-terminal subunits of recombinant mammalian maltase-glucoamylase (MGAM) and sucrase-isomaltase (SI) of varying amounts and digestion periods. Without the aid of α-amylase, Ct-MGAM demonstrated an unexpected rapid and high digestion degree near 80%, while other subunits showed 20 to 30% digestion. These findings suggest that Ct-MGAM assists α-amylase in digesting starch molecules and potentially may compensate for developmental or pathological amylase deficiencies

Evaluation of guided imagery as treatment for recurrent abdominal pain in children: a randomized controlled trial

BACKGROUND: Because of the paucity of effective evidence-based therapies for children with recurrent abdominal pain, we evaluated the therapeutic effect of guided imagery, a well-studied self-regulation technique. METHODS: 22 children, aged 5 – 18 years, were randomized to learn either breathing exercises alone or guided imagery with progressive muscle relaxation. Both groups had 4-weekly sessions with a therapist. Children reported the numbers of days with pain, the pain intensity, and missed activities due to abdominal pain using a daily pain diary collected at baseline and during the intervention. Monthly phone calls to the children reported the number of days with pain and the number of days of missed activities experienced during the month of and month following the intervention. Children with ≤ 4 days of pain/month and no missed activities due to pain were defined as being healed. Depression, anxiety, and somatization were measured in both children and parents at baseline. RESULTS: At baseline the children who received guided imagery had more days of pain during the preceding month (23 vs. 14 days, P = 0.04). There were no differences in the intensity of painful episodes or any baseline psychological factors between the two groups. Children who learned guided imagery with progressive muscle relaxation had significantly greater decrease in the number of days with pain than those learning breathing exercises alone after one (67% vs. 21%, P = 0.05), and two (82% vs. 45%, P < 0.01) months and significantly greater decrease in days with missed activities at one (85% vs. 15%, P = 0.02) and two (95% vs. 77%. P = 0.05) months. During the two months of follow-up, more children who had learned guided imagery met the threshold of ≤ 4 day of pain each month and no missed activities (RR = 7.3, 95%CI [1.1,48.6]) than children who learned only the breathing exercises. CONCLUSION: The therapeutic efficacy of guided imagery with progressive muscle relaxation found in this study is consistent with our present understanding of the pathophysiology of recurrent abdominal pain in children. Although unfamiliar to many pediatricians, guided imagery is a simple, noninvasive therapy with potential benefit for treating children with RAP