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1.
Br J Sports Med ; 53(15): 965-968, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29331994

RESUMEN

OBJECTIVES: The aim of this study was to investigate whether ACL injury (ACLi) or meniscal injury increases the risk of end-stage osteoarthritis (OA) resulting in total knee replacement (TKR). METHODS: A matched case-control study of all TKRs performed in the UK between January 1990 and July 2011 and recorded in the Clinical Practice Research Datalink (CPRD) was undertaken. The CPRD contains longitudinal data on approximately 3.6 million patients. Two controls were selected for each case of TKR, matched on age, sex and general practitioner location as a proxy for socioeconomic status. Individuals with inflammatory arthritis were excluded. The odds of having TKR for individuals with a CPRD-recorded ACLi were compared with those without ACLi using conditional logistic regression, after adjustment for body mass index, previous knee fracture and meniscal injury. The adjusted odds of TKR in individuals with a recorded meniscal injury compared with those without were calculated. RESULTS: After exclusion of individuals with inflammatory arthritis, there were 49 723 in the case group and 104 353 controls. 153 (0.31%) cases had a history of ACLi compared with 41 (0.04%) controls. The adjusted OR of TKR after ACLi was 6.96 (95% CI 4.73 to 10.31). 4217 (8.48%) individuals in the TKR group had a recorded meniscal injury compared with 669 (0.64%) controls. The adjusted OR of TKR after meniscal injury was 15.24 (95% CI 13.88 to 16.69). CONCLUSION: This study demonstrates that ACLi is associated with a sevenfold increased odds of TKR resulting from OA. Meniscal injury is associated with a 15-fold increase odds of TKR for OA.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior/complicaciones , Artroplastia de Reemplazo de Rodilla , Osteoartritis de la Rodilla/etiología , Osteoartritis de la Rodilla/cirugía , Lesiones de Menisco Tibial/complicaciones , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
2.
Acta Orthop ; 90(6): 568-574, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31288595

RESUMEN

Background and purpose - Long-term rates of knee arthroplasty in patients with anterior cruciate ligament (ACL) injury who undergo ligament reconstruction (ACLr) are unclear. We determined this risk of arthroplasty through comparison with the general population.Patients and methods - All patients undergoing an ACLr in England, 1997-2017, were identified from national hospital statistics. Patients subsequently undergoing a knee arthroplasty were identified and survival analysis was performed (survival without undergoing knee arthroplasty). A Cox proportional hazards model was used to identify factors associated with knee arthroplasty. Relative risk of knee arthroplasty (total or partial) in comparison with the general population was determined.Results - 111,212 ACLr patients were eligible for analysis (mean age 29; 77% male). Overall, 0.46% (95% confidence interval [CI] 0.40-0.52) ACLr patients underwent knee arthroplasty within 5 years, 0.97% (CI 0.82-1.2) within 10 years, and 1.8% (CI 1.4-2.3) within 15 years. Knee arthroplasty risk was greater in older age groups and women. In comparison with the general population, the relative risk of undergoing arthroplasty at a younger age (at time of arthroplasty) was elevated: at 30-39 years (risk ratio [RR] 20; CI 11-35), 40-49 years (RR 7.5; CI 5.5-10), and 50-59 years (RR 2.5; CI 1.8-3.5), but not 60-69 years (RR 1.7; CI 0.93-3.2).Interpretation - Patients sustaining an ACL injury who undergo ACLr are at elevated risk of subsequent knee arthroplasty in comparison with the general population. Although the absolute rate of arthroplasty is low, the risk of arthroplasty at a younger age is particularly elevated. When the outcome of shared decision-making is ACLr, this data will help inform patients and clinicians about the long-term risk of requiring knee arthroplasty.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior , Artroplastia de Reemplazo de Rodilla/estadística & datos numéricos , Adulto , Factores de Edad , Anciano , Estudios de Cohortes , Inglaterra/epidemiología , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores Sexuales
3.
Knee Surg Sports Traumatol Arthrosc ; 26(6): 1662-1670, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28831554

RESUMEN

PURPOSE: Patient-specific instrumentation (PSI) has been proposed as a means of improving surgical accuracy and ease of implantation during technically challenging procedures such as unicompartmental knee arthroplasty (UKA). The purpose of this prospective randomised controlled trial was to compare the accuracy of implantation and functional outcome of mobile-bearing medial UKAs implanted with and without PSI by experienced UKA surgeons. METHODS: Mobile-bearing medial UKAs were implanted in 43 patients using either PSI guides or conventional instrumentation. Intra-operative measurements, meniscal bearing size implanted, and post-operative radiographic analyses were performed to assess component positioning. Functional outcome was determined using the Oxford Knee Score (OKS). RESULTS: PSI guides could not be used in three cases due to concerns regarding accuracy and registration onto native anatomy, particularly on the tibial side. In general, similar component alignment and positioning was achieved using the two systems (n.s. for coronal/sagittal alignment and tibial coverage). The PSI group had greater tibial slope (p = 0.029). The control group had a higher number of optimum size meniscal bearing inserted (95 vs 52%; p = 0.001). There were no differences in OKS improvements (n.s). CONCLUSION: Component positioning for the two groups was similar for the femur but less accurate on the tibial side using PSI, often with some unnecessarily deep resections of the tibial plateau. Although PSI was comparable to conventional instrumentation based on OKS improvements at 12 months, we continue to use conventional instrumentation for UKA at our institution until further improvements to the PSI guides can be demonstrated. LEVEL OF EVIDENCE: Therapeutic, Level I.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/instrumentación , Artropatías/cirugía , Articulación de la Rodilla/cirugía , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo de Rodilla/normas , Femenino , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Modelación Específica para el Paciente , Estudios Prospectivos , Recuperación de la Función , Cirugía Asistida por Computador
4.
J Indian Assoc Pediatr Surg ; 22(4): 251-253, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28974881

RESUMEN

Congenital ranula is rare. We report a large, symptomatic, congenital plunging ranula associated with a salivary gland cyst in the neck. To the best of our knowledge, this is the first such reported case. Even though both the cysts had their origin from the sublingual gland, only the cervical cyst had a capsular covering. Herniation of a part of the immature sublingual gland anlage through a congenital mylohyoid defect, its separation, and subsequent maturation could explain this occurrence.

5.
Pediatr Neurosurg ; 51(3): 154-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26872356

RESUMEN

We report 2 cases of ventriculoperitoneal (VP) shunt migration into an inguinal hernia sac. In both cases hernia manifested itself on the right side in late infancy. We attempted to analyse the anatomical and mechanical factors leading to shunt migration as seen in the X-rays of our cases.


Asunto(s)
Migración de Cuerpo Extraño/cirugía , Hernia Inguinal/cirugía , Complicaciones Posoperatorias/cirugía , Derivación Ventriculoperitoneal/efectos adversos , Migración de Cuerpo Extraño/diagnóstico , Hernia Inguinal/diagnóstico , Humanos , Lactante , Masculino , Complicaciones Posoperatorias/diagnóstico
6.
J Indian Assoc Pediatr Surg ; 19(2): 103-5, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24741215

RESUMEN

We report a rare case of uterovaginal duplication in a prepubertal female. The patient also had a permeable ureter (ureter with urine passing through it) subtending a poorly functioning kidney with ectopic insertion in the obstructed hemivagina.

7.
RSC Adv ; 14(38): 27749-27763, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39224636

RESUMEN

Antimony chalcogenides (Sb2(S x Se1-x )3) have drawn attention as a potential semiconducting substance for heterojunction photovoltaic (PV) devices due to the remarkable optoelectronic properties and wide range of bandgaps spanning from 1.1 to 1.7 eV. In this investigation, SCAPS-1D simulation software is employed to design an earth abundant, non-toxic, and cost-effective antimony sulfide-selenide (Sb2(S,Se)3)-based thin-film solar cell (TFSC), where tungsten disulfide (WS2) and cuprous oxide (Cu2O) are used as an electron transport layer (ETL) and hole transport layer (HTL), respectively. The PV performance parameters such as power conversion efficiency, open-circuit voltage (V oc), short-circuit current (J sc), and fill factor (FF) are assessed through adjustments in material properties including thickness, acceptor concentration, bulk defect density of the absorber, defect state of absorber/ETL and HTL/absorber interfaces, operating temperature, work function of the rear electrode, and cell resistances. This analysis aims to validate their collective impact on the overall efficiency of the designed Ni/Cu2O/Sb2(S,Se)3/WS2/FTO/Al TFSC. The optimized physical parameters for the Sb2(S,Se)3 TFSC lead to impressive PV outputs with an efficiency of 30.18%, V oc of 1.02 V, J sc of 33.65 mA cm-2, and FF of 87.59%. Furthermore, an artificial neural network (ANN) machine learning (ML) algorithm predicts the optimal PCE by considering five semiconductor parameters: absorber layer thickness, bandgap, electron affinity, electron mobility, and hole mobility. This model, which has an approximate correlation coefficient (R 2) of 0.999, is able to predict the data with precision. This numerical analysis provides valuable data for the fabrication of an environmentally friendly, economical, and incredibly non-toxic efficient heterojunction TFSC.

8.
Cureus ; 16(6): e62971, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39044877

RESUMEN

BACKGROUND:  Intestinal obstruction in neonates remains a critical medical emergency in the field of pediatric surgery. Clinical conditions often experience a sudden deterioration in their appearance. Multiple factors contribute to unfavorable clinical outcomes in underdeveloped nations. The study was conducted to identify the etiology, management, and outcomes of neonatal intestinal obstruction at a specialized medical facility. METHODS:  This retrospective study included 168 newborns who had to be operated on in the neonatal intensive care unit between 2021 and 2023 due to intestinal obstruction. The clinical and demographic characteristics of the infants, final diagnosis, surgical complications, and mortality rate were documented. In addition, the relationship between risk factors such as birth weight, gestational age, length of surgery, and postoperative problems was evaluated. RESULTS:  The majority of neonatal intestinal obstruction occurred within seven days of birth, with 8-15 days being the second most common. Most babies were born at full term (53.57%) and weighed 2 kg or more (75%). In newborns in our region, duodenal, ileal, jejunal, and colonic atresias were found to be the most common causes of neonatal intestinal obstruction that requires surgery. The study detected 45 postoperative problems, 26.79% of the total. Out of 168 patients, twelve (7.14%) had septicemia, seven (4.17%) had anastomotic leak, seven (4.17%) had aspiration pneumonitis, and two (1.19%) needed re-exploration. Overall mortality was 10.12%, with 17 patients dying. Moreover, 119 patients (70.83%) survived without issues, while 32 (19.05%) survived with complications. CONCLUSION:  Our findings emphasize the significance of promptly diagnosing, intervening, and implementing suitable management approaches to enhance outcomes for newborns with intestinal obstruction. Furthermore, it highlights valuable perspectives for healthcare professionals in enhancing care for this specific group of patients.

9.
Gene ; 933: 148965, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39332601

RESUMEN

Citrobacter werkmanii (C. werkmanii), an opportunistic urinary bacterium that causes diarrhea, is poorly understood. Our research focuses on genetic features that are crucial to disease development, such as pathogenic interactions, antibiotic resistance, virulence genes and genetic variation. Following its morphological, biochemical, and molecular identification, the whole genome of C. werkmanii strain NIB003 was sequenced in Bangladesh for the first time. Despite having around 80% whole genome conservation, the research shows that the Bangladeshi strain forms a separate phylogenetic cluster. This emphasises the genetic variability within C. werkmanii, resulting in particular modifications at the strain level and changes in its ability to cause disease. The results of the genetic diversity analysis indicate that the Bangladeshi sequenced genome is more diverse than the other strains due to the existence of unique features, such as the presence of t-RNA binding domain and N-6 adenine-specific DNA methylases.

10.
Arthroscopy ; 29(5): 906-12, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23628663

RESUMEN

PURPOSE: To determine whether a global rating scale (GRS) with construct validity can also be used to assess the learning curve of individual orthopaedic trainees during simulated arthroscopic knee meniscal repair. METHODS: An established arthroscopic GRS was used to evaluate the technical skill of 19 orthopaedic residents performing a standardized arthroscopic meniscal repair in a bioskills laboratory. The residents had diagnostic knee arthroscopy experience but no experience with arthroscopic meniscal repair. Residents were videotaped performing an arthroscopic meniscal repair on 12 separate occasions. Their performance was assessed by use of the GRS and motion analysis objectively measuring the time taken to complete tasks, path length of the subject's hands, and number of hand movements. One author assessed all 228 videos, whereas 2 other authors rated 34 randomly selected videos, testing the interobserver reliability of the GRS. The validity of the GRS was tested against the motion analysis. RESULTS: Objective assessment with motion analysis defined the surgeon's learning curve, showing significant improvement by each subject over 12 episodes (P < .0001). The GRS also showed a similar learning curve with significant improvements in performance (P < .0001). The median GRS score improved from 15 of 34 (interquartile range, 14 to 17) at baseline to 22 of 34 (interquartile range, 19 to 23) in the final period. There was a moderate correlation (P < .0001, Spearman test) between the GRS and motion analysis parameters (r = -0.58 for time, r = -0.58 for path length, and r = -0.51 for hand movements). The inter-rater reliability among 3 trained assessors using the GRS was excellent (Cronbach α = 0.88). CONCLUSIONS: When compared with motion analysis, an established arthroscopic GRS, with construct validity, also offers a moderately feasible method to monitor the learning curve of individual residents during simulated knee meniscal repair. CLINICAL RELEVANCE: An arthroscopic GRS can be used for monitoring skill improvement during knee meniscal repair and has the potential for use as a training and assessment tool in the real operating room.


Asunto(s)
Artroscopía/educación , Internado y Residencia , Curva de Aprendizaje , Meniscos Tibiales/cirugía , Ortopedia , Competencia Clínica , Educación de Postgrado en Medicina , Evaluación Educacional , Indicadores de Salud , Humanos , Ortopedia/educación , Ortopedia/normas , Estudios de Tiempo y Movimiento
11.
Health Inf Sci Syst ; 10(1): 32, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36387748

RESUMEN

Dengue fever is a disease that has been outbreak worldwide in the last few years. Dengue is a fatal disease; sometimes, it may cause life-threatening complications and even death. Dengue is considered to be one of the critical diseases which is spreading in more than 110 countries. Nearly 45,000 case reports have been found around Bangladesh in the last year. Dengue fever has become a major health hazard in Bangladesh. Hence, early detection would mitigate major casualties of Dengue disease. Distinct studies have been performed concerning Dengue disease; however, no effective study, particularly from Bangladesh's perspective, it seemed that reveals Dengue outbreaks prediction method. In this scenario, this research work aims to analyse the Dengue disease and build an apposite model to predict dengue outbreaks. This paper also aims to find the best technique to early predicts Dengue disease. The real-time data of the patients admitted to different hospitals in Bangladesh is accumulated to achieve the goal of the current research. Then different multilayer perceptron neural networks and a Decision tree are used for Dengue outbreaks prediction. Twenty-five parameters are analysed to find these parameters' infection rates in this work. A comparative study of the developed models' performances is also accomplished to obtain a better Dengue outbreaks prediction model. The results evidence that the Levenberg-Marquardt is the best technique with 97.3% accuracy and 2.7% error in Dengue disease prediction. On the other hand, the Decision tree may have the second choice to assess Dengue disease.

12.
Artículo en Inglés | MEDLINE | ID: mdl-34070834

RESUMEN

Historically, reducing aerosol-based transmission of respired viruses in indoor environments has been of importance for controlling influenza viruses and common-cold rhinoviruses. The present public health emergency associated with SARS-CoV-2 makes this topic critically important. Yet to be tested is the potential effectiveness of simple interventions that create an isolation zone (IZ) for a suspected/confirmed sick or sensitive person requiring quarantine. The intent in existing homes is to find a practical means to mitigate exposure to airborne contaminants. In creating an IZ in an occupied single-family home in the study, four simple strategies were tested. The test configurations were: (1) IZ windows closed with IZ bathroom exhaust ventilation fan off, (2) IZ windows closed with IZ exhaust fan on, (3) IZ window open with IZ exhaust fan off, and (4) IZ window open with IZ exhaust fan on. Incense-generated fine particulate matter (PM2.5) was used as a marker for virus transmission. The measured transfer of PM2.5 from the IZ into the main zone (MZ) of the house enabled us to determine the relative effectiveness of four containment strategies. Collectively, the data from pressure differential (across zones) and PM2.5 measurements suggested that the best containment strategy was achieved through continuously operating the bathroom exhaust fan while keeping the windows closed in the IZ (configuration 2). Interventions using open windows were found to be less reliable, due to variability in wind speed and direction, resulting in an unpredictable and sometimes detrimental pressure differential in the IZ with reference to MZ. Our findings strongly suggest a simple IZ exhaust ventilation strategy has the potential for mitigating the risk from the airborne spread of contaminants, such as SARS-CoV-2.


Asunto(s)
Contaminación del Aire Interior , COVID-19 , Monitoreo del Ambiente , Humanos , Material Particulado/análisis , SARS-CoV-2
13.
Pediatr Surg Int ; 26(12): 1211-5, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20857297

RESUMEN

INTRODUCTION: Congenital pouch colon (CPC) is a pouch-like dilatation of shortened colon associated with anorectal malformation (ARM). The disease is prevalent in northern India. Postoperatively, the continence results are not as good as in other ARMs and there is higher incidence of incontinence and perineal soiling in these patients. The present study aimed to evaluate the pelvic floor and sphincter muscle characteristics in patients of CPC with the help of 64-slice computerized tomography with three-dimensional (3D) volumetric reconstructions of images, thus, to know the overall quality of these muscles in the patients. MATERIALS AND METHODS: The study was conducted in patients admitted over a period of July 2007 to November 2008 in our department. Totally, eight patients of CPC were subjected to 64-slice CT with three-dimensional reconstructions of images and different parameters such as quality of pelvic floor muscles, configuration of vertical and parasagittal fibres, shape and thickness of sphincter muscle complex, attenuation values of sphincters were studied. RESULTS: The 3D reconstructed images of pelvis in patients of CPC showed a well-developed pelvic floor and sphincter muscle complex. The length of the parasagittal fibres, transverse width of the vertical fibres and CT attenuation values of these structures with overall muscle quality were found to be good in these patients. CONCLUSION: In cases of CPC, the pelvic floor muscles including striated muscle complex (vertical and parasagittal fibres) are well developed. Higher rates of incontinence and soiling in CPC are not because of poorly developed pelvic floor and sphincter muscles. Three-dimensional CT can also provide important anatomical information that can help the operating surgeon while performing surgery.


Asunto(s)
Canal Anal/diagnóstico por imagen , Colon/anomalías , Imagenología Tridimensional , Diafragma Pélvico/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Estudios de Casos y Controles , Niño , Anomalías del Sistema Digestivo/diagnóstico por imagen , Dilatación Patológica , Incontinencia Fecal/patología , Humanos , India , Recién Nacido
14.
Bone Joint J ; 102-B(12): 1670-1674, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33249890

RESUMEN

AIMS: To determine mortality risk after first revision total hip arthroplasty (THA) for periprosthetic femoral fracture (PFF), and to compare this to mortality risk after primary and first revision THA for other common indications. METHODS: The study cohort consisted of THAs recorded in the National Joint Registry between 2003 and 2015, linked to national mortality data. First revision THAs for PFF, infection, dislocation, and aseptic loosening were identified. We used a flexible parametric model to estimate the cumulative incidence function of death at 90 days, one year, and five years following first revision THA and primary THA, in the presence of further revision as a competing risk. Analysis covariates were age, sex, and American Society of Anesthesiologists (ASA) grade. RESULTS: A total of 675,078 primary and 74,223 first revision THAs were included (of which 6,131 were performed for PFF). Following revision for PFF, mortality ranged from 9% at 90 days, 21% at one year, and 60% at five years in the highest risk group (males, ≥ 75 years, ASA ≥ 3) to 0.6%, 1.4%, and 5.5%, respectively, for the lowest risk group (females, < 75 years, ASA ≤ 2). Mortality was greater in all groups following first revision THA for PFF than for primary THA. Compared to mortality risk after first revision THA for infection, dislocation, or aseptic loosening, revision for PFF was associated with higher five-year mortality in all groups except males < 75 years with an ASA ≤ 2. CONCLUSION: Mortality risk after revision THA for PFF is high, reaching 60% at five years in the highest risk patient group. In comparison to other common indications for revision, PFF demonstrated the highest overall risk of mortality at five years. These estimates can be used in the surgical decision-making process and when counselling patients and carers regarding surgical risk. Cite this article: Bone Joint J 2020;102-B(12):1670-1674.


Asunto(s)
Artroplastia de Reemplazo de Cadera/mortalidad , Fracturas del Fémur/mortalidad , Fracturas Periprotésicas/mortalidad , Reoperación/mortalidad , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo de Cadera/efectos adversos , Femenino , Fracturas del Fémur/etiología , Fracturas del Fémur/cirugía , Humanos , Masculino , Persona de Mediana Edad , Fracturas Periprotésicas/etiología , Fracturas Periprotésicas/cirugía , Sistema de Registros , Riesgo
15.
Cell Rep ; 31(2): 107519, 2020 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-32294442

RESUMEN

Studies in cultured neurons have established that axon specification instructs neuronal polarization and is necessary for dendrite development. However, dendrite formation in vivo occurs when axon formation is prevented. The mechanisms promoting dendrite development remain elusive. We find that apical dendrite development is directed by a localized cyclic guanosine monophosphate (cGMP)-synthesizing complex. We show that the scaffolding protein Scribble associates with cGMP-synthesizing enzymes soluble-guanylate-cyclase (sGC) and neuronal nitric oxide synthase (nNOS). The Scribble scaffold is preferentially localized to and mediates cGMP increase in dendrites. These events are regulated by kinesin KifC2. Knockdown of Scribble, sGC-ß1, or KifC2 or disrupting their associations prevents cGMP increase in dendrites and causes severe defects in apical dendrite development. Local cGMP elevation or sGC expression rescues the effects of Scribble knockdown on dendrite development, indicating that Scribble is an upstream regulator of cGMP. During neuronal polarization, dendrite development is directed by the Scribble scaffold that might link extracellular cues to localized cGMP increase.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , GMP Cíclico/farmacología , Dendritas/metabolismo , Animales , Axones/metabolismo , Encéfalo/metabolismo , Células Cultivadas , GMP Cíclico/metabolismo , Femenino , Guanilato Ciclasa/metabolismo , Hipocampo/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/fisiología , Ratones , Ratones Endogámicos , Neurogénesis/efectos de los fármacos , Neuronas/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Andamios del Tejido/química , Proteínas Supresoras de Tumor/metabolismo , Proteínas Supresoras de Tumor/fisiología
16.
J Neurosci ; 28(10): 2383-93, 2008 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-18322085

RESUMEN

Neurogenesis, the division, migration, and differentiation of new neurons, occurs throughout life. Brain derived neurotrophic factor (BDNF) has been identified as a potential signaling molecule regulating neurogenesis in the subventricular zone (SVZ), but its functional consequences in vivo have not been well defined. We report marked and unexpected deficits in survival but not proliferation of newly born cells of adult knock-in mice containing a variant form of BDNF [a valine (Val) to methionine (Met) substitution at position 66 in the prodomain of BDNF (Val66Met)], a genetic mutation shown to lead to a selective impairment in activity-dependent BDNF secretion. Utilizing knock-out mouse lines, we identified BDNF and tyrosine receptor kinase B (TrkB) as the critical molecules for the observed impairments in neurogenesis, with p75 knock-out mice showing no effect on cell proliferation or survival. We then localized the activated form of TrkB to a discrete population of cells, type A migrating neuroblasts, and demonstrate a decrease in TrkB phosphorylation in the SVZ of Val66Met mutant mice. With these findings, we identify TrkB signaling, potentially through activity dependent release of BDNF, as a critical step in the survival of migrating neuroblasts. Utilizing a behavioral task shown to be sensitive to disruptions in olfactory bulb neurogenesis, we identified specific impairments in spontaneous olfactory discrimination, but not general olfactory sensitivity or habituation to olfactory stimuli in BDNF mutant mice. Through these observations, we have identified novel links between genetic variant BDNF and adult neurogenesis in vivo, which may contribute to significant impairments in olfactory function.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/genética , Aprendizaje Discriminativo/fisiología , Variación Genética , Bulbo Olfatorio/citología , Bulbo Olfatorio/crecimiento & desarrollo , Vías Olfatorias/fisiología , Sustitución de Aminoácidos/genética , Animales , Factor Neurotrófico Derivado del Encéfalo/biosíntesis , Factor Neurotrófico Derivado del Encéfalo/deficiencia , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Movimiento Celular/genética , Proliferación Celular , Supervivencia Celular/genética , Células Cultivadas , Masculino , Metionina/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Bulbo Olfatorio/fisiología , Estructura Terciaria de Proteína/genética , Receptor trkB/genética , Células Madre/fisiología , Valina/genética
17.
Pediatr Surg Int ; 25(4): 373-5, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19194714

RESUMEN

Anorectal malformation is one among the common congenital malformations usually encountered. The babies usually present early after birth with complaints of missing anal opening, or abnormally placed anal opening, but some patients have presented beyond the early newborn period without recognition of their anorectal malformation. We are presenting a case of a male child with high ARM, who unusually presented first at the age of 45 days, without gross abdominal distension or septicaemia.


Asunto(s)
Canal Anal/anomalías , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Enfermedades del Recto/congénito , Recto/anomalías , Anastomosis Quirúrgica/métodos , Estudios de Seguimiento , Humanos , Recién Nacido , Masculino , Radiografía Abdominal , Enfermedades del Recto/diagnóstico por imagen , Enfermedades del Recto/cirugía
18.
Pediatr Surg Int ; 25(12): 1093-7, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19844726

RESUMEN

BACKGROUND: The diagnosis and management of neonatal pneumoperitoneum revolves around necrotizing enterocolitis (NEC) in most of the published literature. Although NEC remains the major cause of pneumoperitoneum in a neonate, there are several other causes leading to free air in the peritoneal cavity. A number of case reports have appeared describing pneumoperitoneum in a newborn due to rupture of one particular organ, but there have been only few collective reviews on the subject. The present study shares the experience with neonates admitted with a diagnosis of pneumoperitoneum in a pediatric surgical center of a developing country. The various causes of pneumoperitoneum in a newborn, their management and subsequent outcome are described. MATERIALS AND METHODS: The study was conducted in the Department of Pediatric Surgery, CSMMU (upgraded King Georges Medical College), Lucknow, India. All the neonates admitted with a diagnosis of pneumoperitoneum during the period of last 3 years (2005-2008) were retrospectively analyzed. Other neonatal admissions were also retrieved for the same period. Free air was confirmed by erect abdominal X-ray or lateral decubitus films in certain cases. The data sheets were analyzed regarding age of presentation, cause of bowel perforation, management offered and subsequent outcome achieved. All patients of NEC without evidence of perforation were not included in the study (n = 21). RESULTS: Out of total 537 neonatal admissions, 89 (16.5%) neonates were admitted with a diagnosis of pneumoperitoneum. There were 79 (88.7%) males and only 10 (11.6%) female neonates admitted during the study period. All of them had evidence of pneumoperitoneum at the time of admission. The age at presentation ranged from 4 to 32 days. NEC remained the single major cause of pneumoperitoneum in the newborn; however, in 44 (49.4%) patients the cause was not related to NEC. Perforated pouch colon, isolated colonic perforations, caecal perforations, gastric and duodenal perforations were the main causes of pneumoperitoneum not related to NEC. There were seven patients in whom no cause of pneumoperitoneum could be ascertained. The treatment was individualized according to the presentation. Most of the NEC-related perforations were managed by peritoneal drains. Laparotomy was done in rest of the patients. Three patients were managed conservatively. Overall, 19 (21.6%) patients expired. Most of those expired were of low birth weight with NEC and congenital pouch colon with perforation. CONCLUSION: Neonatal pneumoperitoneum remains a surgical emergency and outcome can be lethal if the problem is not addressed early. NEC remains the major cause; however, there are several other important causes of isolated gastrointestinal perforations leading to neonatal pneumoperitoneum. The management should be individualized in these patients and the outcome largely depends on the early recognition of the condition.


Asunto(s)
Drenaje/métodos , Enterocolitis Necrotizante/complicaciones , Perforación Intestinal/complicaciones , Laparotomía/métodos , Neumoperitoneo , Países en Desarrollo , Enterocolitis Necrotizante/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , India , Lactante , Recién Nacido , Perforación Intestinal/diagnóstico , Masculino , Neumoperitoneo/diagnóstico por imagen , Neumoperitoneo/etiología , Neumoperitoneo/cirugía , Pronóstico , Radiografía Abdominal , Estudios Retrospectivos , Rotura Espontánea , Factores de Tiempo
19.
Pediatr Surg Int ; 25(7): 595-9, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19521703

RESUMEN

PURPOSE: Diaphragmatic injuries have been reported to be a predictor of serious associated injuries in trauma and a marker of severity. Because of its rarity in children, the diagnosis is often delayed for months and years, due to overshadowing injuries. Perhaps due to the elasticity of their tissues, traumatic diaphragmatic rupture is uncommon in children. The problem remains a challenging clinical entity and the description of such type of injuries in children remains scarce in the literature. Most of the cases are described along with associated injuries; presence of isolated diaphragmatic injuries in children is unusual. The present study highlights the presentation, diagnosis and management of all of the cases admitted with traumatic diaphragmatic injuries in a single pediatric surgical center. METHODS: We retrospectively studied eight children admitted to our center with a diagnosis of diaphragmatic injury following trauma during a period of 5 years (2003-2008). Relevant information regarding the mode and pattern of injuries were noted in all cases. Type of injury and surgical intervention and outcome of patients were evaluated. RESULTS: Mean age of presentation was 6.8 years (range 2-12 years). Seven patients were males, while one patient was female. Seven patients had a history of blunt trauma abdomen some time back. Only one patient had acute presentation with respiratory distress following road traffic accident, rest of the patients had no associated grievous injury at the time of presentation. One patient presented with features of acute obstruction. All patients could be diagnosed preoperatively and surgical intervention was performed in all cases. The patients recovered well and there was no mortality. CONCLUSION: Diaphragmatic injuries in children are rare. They are usually associated with other severe injuries; however, isolated diaphragmatic injuries occur more frequently in children than adults. A high index of clinical suspicion supported by prompt radiological tests is needed to diagnose these injuries in patients who otherwise have no associated grievous injuries.


Asunto(s)
Diafragma/lesiones , Diafragma/cirugía , Heridas no Penetrantes/diagnóstico por imagen , Heridas no Penetrantes/cirugía , Traumatismos Abdominales/complicaciones , Traumatismos Abdominales/diagnóstico por imagen , Traumatismos Abdominales/cirugía , Niño , Preescolar , Diafragma/diagnóstico por imagen , Femenino , Humanos , India , Masculino , Radiografía Abdominal , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Heridas no Penetrantes/complicaciones
20.
Pediatr Surg Int ; 25(4): 369-72, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19214535

RESUMEN

Survival rates for infants who have esophageal atresia (EA) with or without fistula (TEF) have improved dramatically in the past 50 years. Despite excellent long-term survival for patients with esophageal atresia with tracheoesophageal fistula (EA-TEF), many significant complications can occur. Anastomotic leak at the esophagoesophagostomy site is one such problem resulting in considerable morbidity and mortality in these patients. The methods of esophageal anastomosis for long period has remained the simple end to end anastomosis of esophageal ends with various modifications described from time to time. The present study aims to study the effect on the early postoperative complications, following horizontal mattress suture technique on the primary esophageal anastomosis in cases of EA-TEF. A total of 32 patients with EA-TEF, were operated by our technique during a period of 1 year (2007-2008). The results were compared with the patients (n = 66), who were operated by the traditional simple technique during the same period. Among those patients in whom the esophageal anastomosis was done by horizontal mattress suture, only one had major anastomotic leak, while two had minor anastomotic leaks, as compared to six and nine cases correspondingly in other patients in whom anastomosis was done by simple technique. There was single mortality. We propose that, the utilization of our technique of horizontal mattress suture in primary anastomosis of esophagus in cases of EA-TEF significantly reduces the risk of anastomotic leaks and subsequent morbidity and mortality.


Asunto(s)
Atresia Esofágica/cirugía , Esófago/cirugía , Técnicas de Sutura , Fístula Traqueoesofágica/cirugía , Anastomosis Quirúrgica/métodos , Atresia Esofágica/complicaciones , Estudios de Seguimiento , Humanos , Recién Nacido , Estudios Prospectivos , Fístula Traqueoesofágica/complicaciones , Resultado del Tratamiento
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