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Choledochal cyst (CC) is a disease with a strong Asian preponderance. As laparoscopic surgery has become mainstay in its treatment, the experience in these countries has been phenomenal. However, there are many contentious issues related with the laparoscopic management of CC. In this review article, we will try to answer the contentious questions related to the laparoscopic management of CC. The issues related to aetiology, classification, surgical technique, type of biliary anastomosis, intrahepatic stones and malignancy are discussed. We also discuss the current and future considerations of laparoscopic management with reference to it becoming a gold standard. This article describes the standard surgical approach and will discuss its technical nuances. This article will also discuss the outcome of treatment in different settings of low- and middle-income countries based on lessons learnt by the authors from their experience and research.
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Cells sense and respond to the surrounding microenvironment through binding of membranous integrin to ligands such as the Arg-Gly-Asp (RGD) peptide. Previous studies show that the RGD tether properties on substrate influence cell adhesion and spreading, but few studies have reported strategies to control the tether mobility of RGD on substrate via a physical and noncontact approach. Herein, we demonstrate a novel strategy to tune the tether mobility of RGD on substrate via magnetic force. We conjugate a monolayer of RGD-bearing magnetic nanoparticles (MNPs) on a glass substrate via the flexible and coiled poly(ethylene glycol) linker of large molecular weight (PEG, average MW: 2000), and this increases the RGD tether mobility, which can be significantly reduced by applying magnetic attraction on MNPs. Our data show that high RGD tether mobility delays the early adhesion and spreading of human mesenchymal stem cells (hMSCs), leading to compromised osteogenic differentiation at later stage. In contrast, hMSCs cultured on substrate with restricted RGD tether mobility, achieved either via a shorter PEG linker (MW: 200) or magnetic force, show significantly better adhesion, spreading, and osteogenic differentiation. The control utilizing RGD-bearing nonmagnetic nanoparticles shows no such enhancing effect of magnetic field on cellular events, further supporting our conjecture of magnetic tuning of RGD tether mobility. We hypothesize that high tether mobility of RGD entails additional time and effort by the cells to fully develop traction force and mechanical feedback, thereby delaying the maturation of FAs and activation of subsequent mechanotransduction signaling. Our staining results of vinculin, a critical component of FAs, and Yes-associated protein (YAP), an important mechanosensitive transcriptional factor, support our hypothesis. We believe that our work not only sheds light on the impact of dynamic presentation of cell adhesive ligands on cellular behaviors, which should be taken into consideration for designing novel biomaterials, but also formulate an effective noncontact strategy that enables further investigation on the mechanobiological mechanisms underlying such cellular responses.
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Nanopartículas de Magnetita/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Humanos , Integrinas/metabolismo , Campos Magnéticos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismoRESUMO
BACKGROUND: What is known of neonatal outcomes associated with maternal obesity is limited. The impact on the preterm neonate, delivery room (DR) course and need for neonatal intensive care unit (NICU) admission has not been well established. METHODS: A review was done of our 17 county perinatal regions from the New York State Perinatal Data System database over the 3-year period of 1 January 2010-31 December 2012 for mother/baby dyad information for all live births 34-36 6/7 weeks' gestation. The National Institutes of Health body mass index (BMI) classification was used for maternal BMI with the category definitions of underweight, normal, overweight, obese Level I, obese Level II, and obese Level III. RESULTS: Information was obtained on 2155 women. In this group, 29% had obese BMIs. The incidence of pre-pregnancy diabetes mellitus (DM), DM during gestation and cesarean delivery (CD) in obese mothers was significantly different from normal weight mothers, P<0.001. More infants of Level III mothers required DR resuscitation when compared with infants of normal BMI mothers, 36 vs 16%, P <0.001. The need for assisted ventilation beyond 6 h of age and need for NICU admission was more likely in infants of Level III mothers, P<0.001. Women in all of the obese subgroups had preterm infants with increased birth weights (BWs) compared with preterm infants of normal weight mothers, P<0.001. DISCUSSION: Late preterm infants born to obese mothers are more likely to be delivered by cesarean section and have larger BWs. We found that infants born to obese Level III mothers are much more likely to require assisted ventilation in the DR and NICU admission.
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Cesárea/estatística & dados numéricos , Macrossomia Fetal/epidemiologia , Terapia Intensiva Neonatal/estatística & dados numéricos , Obesidade/complicações , Complicações na Gravidez/epidemiologia , Gestantes , Nascimento Prematuro/epidemiologia , Adulto , Índice de Massa Corporal , Bases de Dados Factuais , Feminino , Macrossomia Fetal/etiologia , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Terapia Intensiva Neonatal/métodos , New York/epidemiologia , Obesidade/epidemiologia , Obesidade/prevenção & controle , Gravidez , Complicações na Gravidez/etiologia , Resultado da Gravidez , Nascimento Prematuro/etiologia , Estudos RetrospectivosRESUMO
INTRODUCTION: Laparoscopic surgery is technically challenging and assessment of competency is necessary to ensure patient safety and guide training. We report on the development of LapPass®, an accessible objective simulation assessment tool with credentialing potential. We provide a preliminary evaluation of its usability and aspects of validity. METHODS: The domains of LapPass® were defined through a consensus process by the executive council of the Association of Laparoscopic Surgeons of Great Britain and Ireland (ALSGBI). A survey of both assessors and trainees was used to test for usability, face and content validity of LapPass®. Internal consistency was tested with Cronbach's alpha, and a composite marker of validity and usability was obtained. RESULTS: LapPass® was developed to consist of four tasks: (1) grasping and manipulation, (2) simulated appendicectomy, (3) cutting a disk and (4) intracorporeal suturing. A total of 76 participants contributed to the evaluation of LapPass®: 13 assessors and 63 trainees. For assessors, Cronbach's alpha for usability of tasks 1-4 was 0.84, 0.84, 0.76 and 0.86, whereas validity was 0.80, 0.85, 0.88, 0.95, respectively. For trainees, Cronbach's alpha was 0.75, 0.77, 0.80 and 0.85 for usability, and 0.79, 093, 0.87 and 0.91 for validity. Consensus was that each task was usable and had face and content validity, with median scores of 4.0 or higher (interquartile range 0.0-1.0). CONCLUSION: LapPass® has potential for the objective assessment of basic laparoscopic skills but further research is required to explore its predictive capabilities in a clinical setting.
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Laparoscopia , Cirurgiões , Competência Clínica , Simulação por Computador , Humanos , Laparoscopia/educação , Reprodutibilidade dos Testes , SuturasAssuntos
Comportamento de Escolha , Tomada de Decisões , Segurança do Paciente , Nascimento Vaginal Após Cesárea/ética , Nascimento Vaginal Após Cesárea/legislação & jurisprudência , Aconselhamento , Documentação , Feminino , Humanos , Consentimento Livre e Esclarecido , Tocologia/ética , Tocologia/legislação & jurisprudência , Complicações do Trabalho de Parto , Aceitação pelo Paciente de Cuidados de Saúde , Autonomia Pessoal , Relações Médico-Paciente , Gravidez , Atenção Primária à Saúde , Reino UnidoRESUMO
Bacterial foodborne pathogens are a significant health burden and the recent emergence of pathogenic resistant strains due to the excessive use of antibiotics makes it more difficult to effectively treat infections as a result of contaminated food. Awareness of this impending health crisis has spurred the search for alternative antimicrobials with natural plant antimicrobials being among the more promising candidates as these substances have good acceptability and likely low toxicity levels as they have long been used in traditional medicines. Resveratrol (3,5,4'-trihydroxystilbene) is a naturally occurring stilbenoid which has been gaining considerable attention in medical field due to its diverse biological activities - it has been reported to exhibit antioxidant, cardioprotective, anti-diabetic, anticancer, and antiaging properties. Given that resveratrol is phytoalexin, with increased synthesis in response to infection by phytopathogens, there has been interest in exploring its antimicrobial activity. This review aims to provide an overview of the published data on the antibacterial activity of resveratrol against foodborne pathogens, its mechanisms of action as well as its possible applications in food packing and processing; in addition we also summarize the current data on its potential synergism with known antibacterials and future research and applications.
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Doença de Addison/diagnóstico , Doença de Addison/tratamento farmacológico , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/tratamento farmacológico , Adulto , Anti-Inflamatórios/uso terapêutico , Feminino , Fludrocortisona/uso terapêutico , Humanos , Hidrocortisona/uso terapêutico , Gravidez , Segundo Trimestre da GravidezRESUMO
Chromoendoscopy with methylene blue has been proposed to improve targeting of biopsies to specialised intestinal metaplasia and dysplasia in Barrett's oesophagus. However, methylene blue can induce oxidative damage of DNA when photosensitised by white light. We show that damage to DNA is increased in Barrett's mucosa after chromoendoscopy with methylene blue, an effect apparently dependent on presence of both methylene blue and endoscopic white light. Exposure of Barrett's mucosa to DNA damage during endoscopy warrants caution since it could accelerate carcinogenesis. This risk needs to be carefully balanced against the possible benefit of improved early detection of preneoplastic lesions with methylene blue chromoendoscopy.
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Esôfago de Barrett/patologia , Dano ao DNA , Esofagoscopia/efeitos adversos , Luz/efeitos adversos , Azul de Metileno/efeitos adversos , Adulto , Idoso , Esôfago de Barrett/diagnóstico , Neoplasias Esofágicas/etiologia , Neoplasias Esofágicas/patologia , Esofagoscopia/métodos , Feminino , Humanos , Masculino , Azul de Metileno/efeitos da radiação , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/etiologia , Lesões Pré-Cancerosas/patologiaRESUMO
We report a case of a 33-year-old female presenting with right sided abdominal pain, a right iliac fossa mass and right hydronephrosis. The mass was subsequently shown to represent an isolated desmoid tumour compromising the adjacent ureter. The patient had no predisposing factors for this pathology. This is an uncommon occurrence and we discuss the imaging features and differential diagnosis.
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Fibromatose Abdominal/complicações , Hidronefrose/etiologia , Obstrução Ureteral/etiologia , Adulto , Feminino , Fibromatose Abdominal/diagnóstico por imagem , Humanos , Hidronefrose/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Obstrução Ureteral/diagnóstico por imagemRESUMO
OBJECTIVE: To determine neonatal outcome at 7 months of corrected age in very low birth weight (VLBW) infants with placental chorioamnionitis. METHODS: We conducted a cohort study of 287 VLBW infants delivered as a result of preterm premature rupture of membranes (PROM) or preterm labor. Control subjects (n = 123) had placentas with absent umbilical cord inflammation and absent or low-grade membrane inflammation. Case subjects (n = 164) had moderate membrane inflammation or any umbilical cord inflammation. Neonatal and 7-month outcomes were compared. A power analysis showed that 98 total subjects were needed to reject the two-sided null hypothesis with a difference in mean Bayley index scores of at least 8. RESULTS: Infants in the study group had significantly more preterm PROM, antenatal antibiotics, lower birth weight, lower gestational age, longer duration of ruptured membranes, and clinical chorioamnionitis. Intraventricular hemorrhage occurred more commonly in infants with placentas demonstrating chorioamnionitis (relative risk = 1.6, 95% confidence interval 1.1, 2.4, P =.013). One hundred sixty-seven (69%) of the 243 surviving infants had 7-month follow-up. There was no difference between cases and controls in mean Bayley mental developmental index (93 compared with 90, P =.25), psychomotor developmental index (89 compared with 90, P =.68), or in the number of infants that were developmentally delayed. CONCLUSION: Despite a higher frequency of intraventricular hemorrhage, no difference in developmental scores was detected at 7 months of corrected age in VLBW infants with histologic chorioamnionitis.
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Desenvolvimento Infantil , Corioamnionite/complicações , Recém-Nascido de muito Baixo Peso/crescimento & desenvolvimento , Resultado da Gravidez , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Ruptura Prematura de Membranas Fetais , Humanos , Lactente , Recém-Nascido , Masculino , Prontuários Médicos , Trabalho de Parto Prematuro , GravidezRESUMO
OBJECTIVE: To determine the effect of exposure to chorioamnionitis on developmental outcome in very low birth weight (VLBW) infants. METHODS: Five hundred four maternal charts (97% of all VLBW infants delivered from 1990 to 1994) were reviewed. A historical cohort study of the 330 infants delivered secondary to preterm premature rupture of membranes or preterm labor was performed. Case subjects (71) were delivered of mothers with chorioamnionitis by clinical criteria; control subjects (259) were delivered of mothers without chorioamnionitis. Bayley index scores at 7 months' corrected age and special care nursery outcomes were compared. One hundred seventy-three subjects were necessary to reject the two-sided null hypothesis with 80% power with a difference in mean Bayley index scores of at least 8. RESULTS: Neonatal sepsis (8.5% compared with 1.9%; odds ratio [OR] = 4.7, 95% confidence interval [CI] 1.4, 15.9, P = .015) and a low 5-minute Apgar (72% compared with 55%; OR = 2.1, CI 1.2, 3.8, P = .012) occurred more frequently in the chorioamnionitis group. One hundred eighty-seven (68%) of 273 surviving neonates had follow-up. Cases and controls were similar in mean Bayley mental developmental index (91.2 compared with 91.8, P = .84), Bayley psychomotor developmental index (89.8 compared with 89.1, P = .82), and number of infants developmentally delayed. Duration of exposure to chorioamnionitis did not affect neonatal outcome. CONCLUSION: Despite higher rates of sepsis and low Apgar scores, no difference in outcome at 7 months of corrected age was detected in VLBW infants exposed to chorioamnionitis. Contemporary neonatal management may reduce the adverse effects of this exposure.
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Corioamnionite , Doenças do Recém-Nascido/epidemiologia , Recém-Nascido de muito Baixo Peso , Adulto , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , GravidezRESUMO
HYPOTHESIS: Since the early 1990s, the laparoscopic technique has been increasingly used for the treatment of perforated peptic ulcer. It is important to validate a risk scoring system that can stratify patients into various risk groups before comparing the treatment outcome of laparoscopic repair against that of conventional open surgery. The scoring system should be able to predict the likelihood of mortality and morbidity. Boey score and APACHE II (Acute Physiology and Chronic Health Evaluation II) score may be of use in patient stratification. DESIGN: Retrospective review of relevant case notes by one reviewer. SETTING: A teaching hospital treating 0. 5 million to 1 million patients during the study period. PATIENTS: Patients operated on for perforated peptic ulcer between January 1989 and December 1998. Patients treated conservatively were excluded. MAIN OUTCOME MEASURES: Mortality and postoperative complications (morbidity). RESULTS: A total of 436 patients (365 male and 71 female) with a mean +/- SD age of 51.5 +/- 18.3 years (range, 14-92 years) were studied. Duodenal perforation accounted for 344 (78.9%) of 436 cases. The mortality rate was 7.8% (34/436), and 89 patients had postoperative complications. Multivariate analysis demonstrated that only the APACHE II score predicted both mortality and morbidity. Although the Boey score predicted mortality, it failed to predict morbidity. However, the Boey score predicted the chance of conversion in patients undergoing laparoscopic repair. CONCLUSIONS: The APACHE II score may be a useful tool for stratifying patients into various risk groups, and the Boey score might select appropriate patients for laparoscopic repair.
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APACHE , Úlcera Duodenal/complicações , Úlcera Péptica Perfurada/mortalidade , Úlcera Péptica Perfurada/cirurgia , Complicações Pós-Operatórias/epidemiologia , Feminino , Adesivo Tecidual de Fibrina , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Morbidade , Análise Multivariada , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Técnicas de SuturaRESUMO
BACKGROUND: Laparotomy remains the commonest intervention in patients with abdominal complications of laparoscopic surgery. Our own policy is to employ relaparoscopy to avoid diagnostic delay and unnecessary laparotomy. The results of using this policy in patients with suspected intra-abdominal complications following laparoscopic cholecystectomy are reviewed. METHODS: Data were collected from laparoscopic cholecystectomies carried out by five consultant surgeons in one center. Details of relaparoscopy for complications were analyzed. RESULTS: Thirteen patients underwent relaparoscopy within 7 days of laparoscopic cholecystectomy for intra-abdominal bleeding (2 patients) or abdominal pain (11 patients). The causes of pain were subhepatic haematoma (1), acute pancreatitis (1), small bowel injury (1), and minor bile leakage (6). In 2 patients no cause was identified. Twelve patients were managed laparoscopically and 1 patient required laparotomy. Median stay after relaparoscopy was 7 days (range 2 to 19). CONCLUSIONS: Exploratory laparotomy can be avoided by prompt relaparoscopy in the majority of patients with abdominal complications of laparoscopic cholecystectomy.
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Colecistectomia Laparoscópica/efeitos adversos , Laparoscopia , Complicações Pós-Operatórias/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Colecistectomia Laparoscópica/estatística & dados numéricos , Feminino , Humanos , Laparoscopia/métodos , Laparoscopia/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Prospectivos , Reoperação/métodos , Reoperação/estatística & dados numéricos , Fatores de TempoRESUMO
BACKGROUND: Controversy surrounds the choice of laparoscopic cardiomyotomy as the primary treatment for achalasia or a second-line treatment following the failure of nonsurgical treatment. Laparoscopic cardiomyotomy can be more difficult technically following pneumatic dilatations. The aim of this study was to compare the outcome obtained with primary laparoscopic cardiomyotomy to that achieved when the procedure is performed following failed pneumatic dilatation. METHODS: Laparoscopic cardiomyotomy was performed in seven patients following a median of four pneumatic dilatations (group A) and in five patients as their primary treatment (group B). Outcome was measured using manometry, a modified DeMeester symptom scoring system, and a quality-of-life questionnaire. RESULTS: There were no significant differences between groups A and B in sex, age, preoperative modified DeMeester score, or mean barrier pressure. Six of seven group A patients had evidence of periesophageal and submucosal fibrosis at surgery, but this condition was not seen in group B patients. The operative time was slightly longer in group A patients. There was no difference in complication rates (one primary hemorrhage in group A and one esophageal perforation in group B), and both groups had a significantly improved modified DeMeester score at 6 weeks and at long-term follow-up (median, 26 months). Eleven of 12 patients said that they would choose laparoscopic cardiomyotomy as their primary treatment if newly diagnosed with achalasia. CONCLUSIONS: Laparoscopic cardiomyotomy is safe and effective as a primary or second-line treatment following pneumatic dilatations in patients with achalasia.
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Cárdia/cirurgia , Cateterismo/efeitos adversos , Fundoplicatura/métodos , Laparoscopia/métodos , Adulto , Idoso , Cateterismo/métodos , Acalasia Esofágica/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
BACKGROUND: The aim of this study was to compare micropuncture laparoscopic cholecystectomy (MPLC), with three 3.3-mm cannulas and one 10-mm cannula with conventional laparoscopic cholecystectomy (CLC). METHODS: Patients were randomized to undergo either CLC or MPLC. The duration of each operative stage and the procedure were recorded. Interleukin-6 (IL-6), adrenocorticotropic hormone (ACTH), and vasopressin were sampled for 24 h. Visual analogue pain scores (VAPS) and analgesic consumption were recorded for 1 week. Pulmonary function and quality of life (EQ-5D) were monitored for 4 weeks. Statistical analysis was performed using the Mann-Whitney test or Fisher's exact test. Results are expressed as median (interquartile range). RESULTS: Forty-four patients entered the study, but four were excluded due to unsuspected choledocholithiasis (n = 3) or the need to reschedule surgery (n = 1). The groups were comparable in terms of age, duration of symptoms, and indications for surgery. Total operative time was similar (CLC, 63 [52-81] min vs MPLC 74 [58-95] min; p = 0.126). However, time to place the cannulas after skin incision (CLC, 5:42 [3:45-6:37] min vs MPLC, 7:38 [5:57-10:15] min; p = 0.015) and to clip the cystic duct after cholangiography (CLC, 1:05 [0:40-1:35] min vs MPLC, 3:45 [2:26-7:49] min; p <0.001) were significantly longer for MPLC. Six CLC patients and one MPLC patient required postoperative parenteral opiates (p = 0.04). Oral analgesic consumption was similar in both groups (p = 0.217). Median VAPS were lower at all time points for MPLC, but this finding was not significant (p = 0.431). There were no significant differences in postoperative stay, IL-6, ACTH or vasopressin responses, pulmonary function, or EQ-5D scores. CONCLUSIONS: The thinner instruments did not significantly increase the total duration of the procedure. MPLC reduced the use of parenteral analgesia postoperatively, which may prove beneficial for day case patients, but it did not have a significant impact on laboratory variables, lung function or quality of life.
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Colecistectomia Laparoscópica/métodos , Colecistectomia/métodos , Punções/métodos , Hormônio Adrenocorticotrópico/sangue , Adulto , Analgesia/efeitos adversos , Analgesia/métodos , Colecistectomia/instrumentação , Colecistectomia Laparoscópica/instrumentação , Vesícula Biliar/cirurgia , Humanos , Interleucina-6/sangue , Pessoa de Meia-Idade , Náusea/etiologia , Medição da Dor/métodos , Complicações Pós-Operatórias , Qualidade de Vida , Testes de Função Respiratória/métodos , Estresse Fisiológico/sangue , Vasopressinas/sangue , Vômito/etiologiaRESUMO
Longitudinal studies of rodeo injuries are rare. We prospectively investigated injuries in professional rodeo in Canada over a 5-year period. Our specific interests included injury incidence density in specific rodeo events, risk factors such as past injury, and the incidence of head injury. Of 323 professional rodeos from 1995 through 1999, 63 rodeos provided a convenience sample. These rodeos were selected because the Canadian Professional Rodeo Sport Medicine Team was in attendance at these events, thus providing both competitor health care and data collection. Four hundred fifty-one injuries were reported during 30,564 competitor-exposures. The greatest injury frequency and injury incidence density were in the rough stock events (bull riding, bareback riding, and saddle bronc). Bull riding accounted for the greatest injury frequency (141) and incidence density (32.2 injuries per 1000 competitor-exposures). Bull riding had a relative injury risk of 1.32 when compared with bareback riding; bareback riding had a relative injury risk of 1.39 when compared with saddle bronc riding. Concussions accounted for 8.6% of all reported injuries. Concussions and other head injuries (65) were second only to knee injuries (76) in frequency of injury to specific body parts. This concussion frequency is higher than has previously been reported.
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Traumatismos em Atletas/epidemiologia , Concussão Encefálica/epidemiologia , Concussão Encefálica/etiologia , Canadá/epidemiologia , Traumatismos Craniocerebrais/epidemiologia , Traumatismos Craniocerebrais/etiologia , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/etiologia , Humanos , Incidência , Estudos Prospectivos , Entorses e Distensões/epidemiologia , Entorses e Distensões/etiologiaRESUMO
A new environmental enrichment device, termed a "foraging/grooming board," was presented to 8 individually housed rhesus monkeys for the explicit purpose of reducing the level of aberrant behaviors manifested by these animals. The device, consisting of a piece of plexiglass covered with artificial fleece, had particles of food treats rubbed into it and was attached to the outside of each animal's home cage. All animals foraged from the board to the point that a significant reduction in the level of abnormal behavior was noted. Most animals also groomed the fleece covering the board, utilizing the same motor patterns that would be directed toward grooming another monkey. These boards are inexpensive to construct and easy to sanitize, and do not require placing animal facility personnel at risk to maintain them.
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Although previous work identified 12 complementation groups with possible roles in virus assembly, currently only one frog virus 3 protein, the major capsid protein (MCP), has been linked with virion formation. To identify other proteins required for assembly, we used an antisense morpholino oligonucleotide to target 53R, a putative myristoylated membrane protein, and showed that treatment resulted in marked reductions in 53R levels and a 60% drop in virus titers. Immunofluorescence assays confirmed knock down and showed that 53R was found primarily within viral assembly sites, whereas transmission electron microscopy detected fewer mature virions and, in some cells, dense granular bodies that may represent unencapsidated DNA-protein complexes. Treatment with a myristoylation inhibitor (2-hydroxymyristic acid) resulted in an 80% reduction in viral titers. Collectively, these data indicate that 53R is an essential viral protein that is required for replication in vitro and suggest it plays a critical role in virion formation.