RESUMO
PURPOSE: We studied the current management trends for extraperitoneal bladder injuries and evaluated the use of operative repair versus catheter drainage, and the associated complications with each approach. MATERIALS AND METHODS: We prospectively collected data on bladder trauma from 20 level 1 trauma centers across the United States from 2013 to 2018. We excluded patients with intraperitoneal bladder injury and those who died within 24 hours of hospital arrival. We separated patients with extraperitoneal bladder injuries into 2 groups (catheter drainage vs operative repair) based on their initial management within the first 4 days and compared the rates of bladder injury related complications among them. Regression analyses were used to identify potential predictors of complications. RESULTS: From 323 bladder injuries we included 157 patients with extraperitoneal bladder injuries. Concomitant injuries occurred in 139 (88%) patients with pelvic fracture seen in 79%. Sixty-seven patients (43%) initially underwent operative repair for their extraperitoneal bladder injuries. The 3 most common reasons for operative repair were severity of injury or bladder neck injury (40%), injury found during laparotomy (39%) and concern for pelvic hardware contamination (28%). Significant complications were identified in 23% and 19% of the catheter drainage and operative repair groups, respectively (p=0.55). The only statistically significant predictor for complications was bladder neck or urethral injury (RR 2.69, 95% 1.21-5.97, p=0.01). CONCLUSIONS: In this large multi-institutional cohort, 43% of patients underwent surgical repair for initial management of extraperitoneal bladder injuries. We found no significant difference in complications between the initial management strategies of catheter drainage and operative repair. The most significant predictor for complications was concomitant urethral or bladder neck injury.
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Bexiga Urinária/lesões , Ferimentos não Penetrantes/cirurgia , Ferimentos Penetrantes/cirurgia , Adulto , Drenagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo , Ossos Pélvicos/lesões , Estudos Prospectivos , Estados UnidosRESUMO
A key component in T cell activation is the endosomal recycling of receptors to the cell surface, thereby allowing continual integration of signaling and Ag recognition. One protein potentially involved in TCR transport is sorting nexin 17 (SNX17). SNX proteins have been found to bind proteins involved in T cell activation, but specifically the role of SNX17 in receptor recycling and T cell activation is unknown. Using immunofluorescence, we find that SNX17 colocalizes with TCR and localizes to the immune synapse in T- conjugates. Significantly, knockdown of the SNX17 resulted in fewer T-APC conjugates, lower CD69, TCR, and LFA-1 surface expression, as well as lower overall TCR recycling compared with control T cells. Lastly, we identified the 4.1/ezrin/radixin/moesin domain of SNX17 as being responsible in the binding and trafficking of TCR and LFA-1 to the cell surface. These data suggest that SNX17 plays a role in the maintenance of normal surface levels of activating receptors and integrins to permit optimum T cell activation at the immune synapse.
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Integrinas/metabolismo , Ativação Linfocitária/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Nexinas de Classificação/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Sequência de Aminoácidos , Linhagem Celular , Membrana Celular/metabolismo , Humanos , Sinapses Imunológicas/metabolismo , Células Jurkat , Ativação Linfocitária/genética , Antígeno-1 Associado à Função Linfocitária/metabolismo , Lisossomos/metabolismo , Dados de Sequência Molecular , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Transporte Proteico , Proteólise , Alinhamento de Sequência , Nexinas de Classificação/química , Nexinas de Classificação/genéticaRESUMO
PURPOSE: We evaluated perioperative complications in patients undergoing primary artificial urinary sphincter placement and the potential impact of these complications on device outcomes. MATERIALS AND METHODS: During the 2-year period from 2012 to 2014 we retrospectively evaluated the outcomes of 197 consecutive artificial urinary sphincter implantation procedures performed at our institution for post-prostatectomy incontinence. Of these cases 100 that were primary implantations comprise the study cohort. Perioperative complications, defined as those occurring within 6 weeks postoperatively, were classified by the Clavien-Dindo classification. After office evaluation at 6 weeks patients were followed for symptoms. Patient followup was obtained through office examination and telephone correspondence. RESULTS: Patients undergoing primary artificial urinary sphincter implantation had a median age of 71.5 years (IQR 66, 76). The overall rate of any complication (Clavien I-V) within 6 weeks of surgery was 35%, including urinary retention in 31% of cases, cellulitis in 1%, device infection in 2% and urethral erosion in 2%. No significant differences in pertinent clinical comorbidities such as age (p = 0.69), hypertension (p = 0.95), coronary artery disease (p = 0.57), diabetes mellitus (p = 0.17), body mass index (p = 0.47), prior pelvic radiation therapy (p = 0.45), prior urethral sling placement (p = 0.91) or transcorporeal urethral cuff placement (p = 0.22) were found between patients with and without complications. Median followup was similar between those with and without postoperative urinary retention (p = 0.14). Postoperative urinary retention was associated with adverse 6-month device survival (76% vs 89%, p = 0.04). CONCLUSIONS: The most common complication of artificial urinary sphincter placement is urinary retention. Serious adverse events following artificial urinary sphincter placement are rare. Postoperative urinary retention is associated with adverse short-term device survival rates.
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Incontinência Urinária/cirurgia , Esfíncter Urinário Artificial/efeitos adversos , Idoso , Humanos , Masculino , Prostatectomia/efeitos adversos , Estudos Retrospectivos , Incontinência Urinária/etiologia , Retenção Urinária/etiologiaRESUMO
INTRODUCTION: Acquired buried penis (ABP) is a urologic condition that has significant morbidity and negative effect on quality of life, including but not limited to sexual function, hygiene, micturition, and self-image. This disease process is characterized by a wide degree of variability and severity that requires a patient-specific approach and significant flexibility on the surgeon's behalf. AIM: To review and present the current evaluation and surgical management of this rare and complex patient population. METHODS: A structured review of the English language literature from 1970 to June 2018 was performed using the PubMed and MEDLINE medical databases. Queried terms included "buried penis," "concealed penis," "hidden penis," "adult buried penis," "cicatricial penis," "trapped penis," "inconspicuous penis," "scrotoplasty and obesity," "penile release," "penile skin graft," "penile reconstruction," and "pubic lift." Papers were individually reviewed for their utility and applicability to the management of adult ABP. Manuscripts focusing on pediatric patients were excluded. MAIN OUTCOME MEASURE: Current surgical management options for adult ABP are heterogenous but focus on preserving shaft length while improving cosmesis and voiding function. RESULTS: Surgical versatility remains critical for successful outcomes. However, recent advances in surgical techniques for correction of adult ABP focus on the use of skin grafting to cover the shaft, along with lipectomy and/or scrotoplasty to further aid penile exposure. Collaboration with multiple surgical services is often required to achieve optimal outcomes. CONCLUSION: ABP is a complex urologic condition with equally complex surgical treatment options. Care must be taken when planning a surgical intervention, and support from plastic or general surgery may be required. However, with careful selection, surgical correction frequently leads to significant improvement in function and quality of life. Smith-Harrison LI, Piotrowski J, Machen GL, et al. Acquired Buried Penis in Adults: A Review of Surgical Management. Sex Med Rev 2020;8:150-157.
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Doenças do Pênis/cirurgia , Adulto , Humanos , Masculino , Doenças do Pênis/diagnóstico , Doenças do Pênis/etiologia , Pênis/cirurgia , Transplante de PeleRESUMO
Burkholderia cenocepacia is an opportunistic bacterial pathogen that causes severe pulmonary infections in cystic fibrosis and chronic granulomatous disease patients. B. cenocepacia can survive inside infected macrophages within the B. cenocepacia-containing vacuole (BcCV) and to elicit a severe inflammatory response. By inactivating the host macrophage Rho GTPases, the bacterial effector TecA causes depolymerization of the cortical actin cytoskeleton. In this study, we find that B. cenocepacia induces the formation of large cytosolic F-actin clusters in infected macrophages. Cluster formation requires the nucleation-promoting factor WASH, the Arp2/3 complex, and TecA. Inactivation of Rho GTPases by bacterial toxins is necessary and sufficient to induce the formation of the cytosolic actin clusters. By hijacking WASH and Arp2/3 activity, B. cenocepacia disrupts interactions with the endolysosomal system, thereby delaying the maturation of the BcCV.
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Citoesqueleto de Actina/metabolismo , Burkholderia cenocepacia/fisiologia , Proteínas dos Microfilamentos/metabolismo , Fagossomos/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Animais , Toxinas Bacterianas/metabolismo , Células da Medula Óssea/citologia , Feminino , Lisossomos/metabolismo , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas dos Microfilamentos/deficiência , Proteínas dos Microfilamentos/genética , Células RAW 264.7 , Proteínas de Transporte Vesicular/deficiência , Proteínas de Transporte Vesicular/genética , Proteínas rho de Ligação ao GTP/antagonistas & inibidoresRESUMO
BACKGROUND: In 2018, the American Association for the Surgery of Trauma (AAST) published revisions to the renal injury grading system to reflect the increased reliance on computed tomography scans and non-operative management of high-grade renal trauma (HGRT). We aimed to evaluate how these revisions will change the grading of HGRT and if it outperforms the original 1989 grading in predicting bleeding control interventions. METHODS: Data on HGRT were collected from 14 Level-1 trauma centers from 2014 to 2017. Patients with initial computed tomography scans were included. Two radiologists reviewed the scans to regrade the injuries according to the 1989 and 2018 AAST grading systems. Descriptive statistics were used to assess grade reclassifications. Mixed-effect multivariable logistic regression was used to measure the predictive ability of each grading system. The areas under the curves were compared. RESULTS: Of the 322 injuries included, 27.0% were upgraded, 3.4% were downgraded, and 69.5% remained unchanged. Of the injuries graded as III or lower using the 1989 AAST, 33.5% were upgraded to grade IV using the 2018 AAST. Of the grade V injuries, 58.8% were downgraded using the 2018 AAST. There was no statistically significant difference in the overall areas under the curves between the 2018 and 1989 AAST grading system for predicting bleeding interventions (0.72 vs. 0.68, p = 0.34). CONCLUSION: About one third of the injuries previously classified as grade III will be upgraded to grade IV using the 2018 AAST, which adds to the heterogeneity of grade IV injuries. Although the 2018 AAST grading provides more anatomic details on injury patterns and includes important radiologic findings, it did not outperform the 1989 AAST grading in predicting bleeding interventions. LEVEL OF EVIDENCE: Prognostic and Epidemiological Study, level III.
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Hemorragia/diagnóstico por imagem , Escala de Gravidade do Ferimento , Rim/lesões , Adulto , Classificação , Feminino , Hemorragia/etiologia , Hemorragia/cirurgia , Humanos , Rim/diagnóstico por imagem , Rim/cirurgia , Masculino , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: To evaluate contemporary trends in the management of small renal masses and how patient age has impacted practice patterns. METHODS: Using the NCDB Participant User File (PUF) from 2002 to 2015, we identified patients with T1a renal masses. The initial treatment was categorized as radical nephrectomy (RN), partial nephrectomy (PN), ablation, or active surveillance (AS). A multinominal logistic regression model was used to identify significant factors impacting treatment. RESULTS: We identified 75,691 patients for analysis. RN, PN, and ablation accounted for 28%, 52%, and 12%, respectively, while 8% were managed with AS. In the past decade the likelihood of undergoing PN, ablation, or surveillance compared to RN has consistently increased, independent of age, sex, race, comorbidity, tumor size, or institution. As age increased, patients were independently less likely to undergo PN and more likely to be managed with ablation or AS. Compared to patients under 40 years of age, patients between 70 and 79 were far less likely to undergo PN (RR 0.58, P< .01), and far more likely to undergo either ablation (RR 5.53, P< .01) or AS (RR 3.7, P< .01). CONCLUSION: Trends in small renal mass management continue to evolve, with PN supplanting RN over the past decade as the predominant surgical treatment. Age significantly impacts treatment selection, particularly in older cohorts whom are much more likely to undergo ablation or AS. While the use of minimally invasive therapies has increased over the past decade, AS lags behind despite quality data supporting its use. When controlling for multiple clinical factors, PN, ablation and surveillance have consistently increased in utilization compared to RN.
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Carcinoma de Células Renais/terapia , Neoplasias Renais/terapia , Adulto , Fatores Etários , Idoso , Carcinoma de Células Renais/patologia , Feminino , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Nefrectomia/métodos , Nefrectomia/tendências , Carga Tumoral , Conduta Expectante/tendênciasRESUMO
BACKGROUND: Indications for intervention after high-grade renal trauma (HGRT) remain poorly defined. Certain radiographic findings can be used to guide the management of HGRT. We aimed to assess the associations between initial radiographic findings and interventions for hemorrhage after HGRT and to determine hematoma and laceration sizes predicting interventions. METHODS: The Genitourinary Trauma Study is a multicenter study including HGRT patients from 14 Level I trauma centers from 2014 to 2017. Admission computed tomography scans were categorized based on multiple variables, including vascular contrast extravasation (VCE), hematoma rim distance (HRD), and size of the deepest laceration. Renal bleeding interventions included angioembolization, surgical packing, renorrhaphy, partial nephrectomy, and nephrectomy. Mixed-effect Poisson regression was used to assess the associations. Receiver operating characteristic analysis was used to define optimal cutoffs for HRD and laceration size. RESULTS: In the 326 patients, injury mechanism was blunt in 81%. Forty-seven (14%) patients underwent 51 bleeding interventions, including 19 renal angioembolizations, 16 nephrectomies, and 16 other procedures. In univariable analysis, presence of VCE was associated with a 5.9-fold increase in risk of interventions, and each centimeter increase in HRD was associated with 30% increase in risk of bleeding interventions. An HRD of 3.5 cm or greater and renal laceration depth of 2.5 cm or greater were most predictive of interventions. In multivariable models, VCE and HRD were significantly associated with bleeding interventions. CONCLUSION: Our findings support the importance of certain radiographic findings in prediction of bleeding interventions after HGRT. These factors can be used as adjuncts to renal injury grading to guide clinical decision making. LEVEL OF EVIDENCE: Prognostic and Epidemiological Study, Level III and Therapeutic/Care Management, Level IV.
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Traumatismos Abdominais/patologia , Hemorragia/etiologia , Nefropatias/etiologia , Rim/lesões , Ferimentos não Penetrantes/complicações , Traumatismos Abdominais/complicações , Traumatismos Abdominais/diagnóstico por imagem , Adulto , Feminino , Humanos , Rim/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Adulto JovemRESUMO
BACKGROUND: The management of high-grade renal trauma (HGRT) and the indications for intervention are not well defined. The American Association for the Surgery of Trauma (AAST) renal grading does not incorporate some important clinical and radiologic variables associated with increased risk of interventions. We aimed to use data from a multi-institutional contemporary cohort to develop a nomogram predicting risk of interventions for bleeding after HGRT. METHODS: From 2014 to 2017, data on adult HGRT (AAST grades III-V) were collected from 14 level 1 trauma centers. Patients with both clinical and radiologic data were included. Data were gathered on demographics, injury characteristics, management, and outcomes. Clinical and radiologic parameters, obtained after trauma evaluation, were used to predict renal bleeding interventions. We developed a prediction model by applying backward model selection to a logistic regression model and built a nomogram using the selected model. RESULTS: A total of 326 patients met the inclusion criteria. Mechanism of injury was blunt in 81%. Median age and injury severity score were 28 years and 22, respectively. Injuries were reported as AAST grades III (60%), IV (33%), and V (7%). Overall, 47 (14%) underwent interventions for bleeding control including 19 renal angioembolizations, 16 nephrectomies, and 12 other procedures. Of the variables included in the nomogram, a hematoma size of 12 cm contributed the most points, followed by penetrating trauma mechanism, vascular contrast extravasation, pararenal hematoma extension, concomitant injuries, and shock. The area under the receiver operating characteristic curve was 0.83 (95% confidence interval, 0.81-0.85). CONCLUSION: We developed a nomogram that integrates multiple clinical and radiologic factors readily available upon assessment of patients with HGRT and can provide predicted probability for bleeding interventions. This nomogram may help in guiding appropriate management of HGRT and decreasing unnecessary interventions. LEVEL OF EVIDENCE: Prognostic and epidemiological study, level III.
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Hemorragia/etiologia , Nefropatias/etiologia , Rim/lesões , Nomogramas , Adulto , Feminino , Hemorragia/diagnóstico por imagem , Hemorragia/cirurgia , Hemorragia/terapia , Humanos , Escala de Gravidade do Ferimento , Rim/diagnóstico por imagem , Rim/cirurgia , Nefropatias/diagnóstico por imagem , Nefropatias/cirurgia , Nefropatias/terapia , Masculino , Pessoa de Meia-Idade , Medição de Risco , Centros de Traumatologia/estatística & dados numéricos , Resultado do Tratamento , Estados Unidos , Ferimentos não Penetrantes/complicações , Ferimentos não Penetrantes/diagnóstico por imagem , Ferimentos não Penetrantes/cirurgia , Ferimentos não Penetrantes/terapia , Ferimentos Perfurantes/complicações , Ferimentos Perfurantes/diagnóstico por imagem , Ferimentos Perfurantes/cirurgia , Ferimentos Perfurantes/terapia , Adulto JovemRESUMO
BACKGROUND: Excretory phase computed tomography (CT) scan is used for diagnosis of renal collecting system injuries and accurate grading of high-grade renal trauma. However, optimal timing of the excretory phase is not well established. We hypothesized that there is an association between excretory phase timing and diagnosis of urinary extravasation and aimed to identify the optimal excretory phase timing for diagnosis of urinary extravasation. METHODS: The Genito-Urinary Trauma Study collected data on high-grade renal trauma (grades III-V) from 14 Level I trauma centers between 2014 and 2017. The time between portal venous and excretory phases at initial CT scans was recorded. Poisson regression was used to measure the association between excretory phase timing and diagnosis of urinary extravasation. Predictive receiver operating characteristic analysis was used to identify a cutoff point optimizing detection of urinary extravasation. RESULTS: Overall, 326 patients were included; 245 (75%) had excretory phase CT scans for review either initially (n = 212) or only at their follow-up (n = 33). At initial CT with excretory phase, 46 (22%) of 212 patients were diagnosed with urinary extravasation. Median time between portal venous and excretory phases was 4 minutes (interquartile range, 4-7 minutes). Time of initial excretory phase was significantly greater in those diagnosed with urinary extravasation. Increased time to excretory phase was positively associated with finding urinary extravasation at the initial CT scan after controlling for multiple factors (risk ratio per minute, 1.15; 95% confidence interval, 1.09-1.22; p < 0.001). The optimal delay for detection of urinary extravasation was 9 minutes. CONCLUSION: Timing of the excretory phase is a significant factor in accurate diagnosis of renal collecting system injury. A 9-minute delay between the early and excretory phases optimized detection of urinary extravasation. LEVEL OF EVIDENCE: Diagnostic tests/criteria study, level III.
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Rim/lesões , Tomografia Computadorizada por Raios X/métodos , Incontinência Urinária/diagnóstico por imagem , Ferimentos não Penetrantes/complicações , Adulto , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROCRESUMO
BACKGROUND: Pelvic fracture urethral injuries (PFUI) occur in up to 10% of pelvic fractures. It remains controversial whether initial primary urethral realignment (PR) after PFUI decreases the incidence of urethral obstruction and the need for subsequent urethral procedures. We present methodology for a prospective cohort study analyzing the outcomes of PR versus suprapubic cystostomy tube (SPT) after PFUI. METHODS: A prospective cohort trial was designed to compare outcomes between PR (group 1) and SPT placement (group 2). Centers are assigned to a group upon entry into the study. All patients will undergo retrograde attempted catheter placement; if this fails a cystoscopy exam is done to confirm a complete urethral disruption and attempt at gentle retrograde catheter placement. If catheter placement fails, group 1 will undergo urethral realignment and group 2 will undergo SPT. The primary outcome measure will be the rate of urethral obstruction preventing atraumatic passage of a flexible cystoscope. Secondary outcome measures include: subsequent urethral interventions, post-injury complications, urethroplasty complexity, erectile dysfunction (ED) and urinary incontinence rates. RESULTS: Prior studies demonstrate PR is associated with a 15% to 50% reduction in urethral obstruction. Ninety-six men (48 per treatment group) are required to detect a 15% treatment effect (80% power, 0.05 significance level, 20% loss to follow up/death rate). Busy trauma centers treat complete PFUI approximately 1-6 times per year, thus our goal is to recruit 25 trauma centers and enroll patients for 3 years with a goal of 100 or more total patients with complete urethral disruption. CONCLUSIONS: The proposed prospective multi-institutional cohort study should determine the utility of acute urethral realignment after PFUI.
RESUMO
BACKGROUND: The rarity of renal trauma limits its study and the strength of evidence-based guidelines. Although management of renal injuries has shifted toward a nonoperative approach, nephrectomy remains the most common intervention for high-grade renal trauma (HGRT). We aimed to describe the contemporary management of HGRT in the United States and also evaluate clinical factors associated with nephrectomy after HGRT. METHODS: From 2014 to 2017, data on HGRT (American Association for the Surgery of Trauma grades III-V) were collected from 14 participating Level-1 trauma centers. Data were gathered on demographics, injury characteristics, management, and short-term outcomes. Management was classified into three groups-expectant, conservative/minimally invasive, and open operative. Descriptive statistics were used to report management of renal trauma. Univariate and multivariate logistic mixed effect models with clustering by facility were used to look at associations between proposed risk factors and nephrectomy. RESULTS: A total of 431 adult HGRT were recorded; 79% were male, and mechanism of injury was blunt in 71%. Injuries were graded as III, IV, and V in 236 (55%), 142 (33%), and 53 (12%), respectively. Laparotomy was performed in 169 (39%) patients. Overall, 300 (70%) patients were managed expectantly and 47 (11%) underwent conservative/minimally invasive management. Eighty-four (19%) underwent renal-related open operative management with 55 (67%) of them undergoing nephrectomy. Nephrectomy rates were 15% and 62% for grades IV and V, respectively. Penetrating injuries had significantly higher American Association for the Surgery of Trauma grades and higher rates of nephrectomy. In multivariable analysis, only renal injury grade and penetrating mechanism of injury were significantly associated with undergoing nephrectomy. CONCLUSION: Expectant and conservative management is currently utilized in 80% of HGRT; however, the rate of nephrectomy remains high. Clinical factors, such as surrogates of hemodynamic instability and metabolic acidosis, are associated with nephrectomy for HGRT; however, higher renal injury grade and penetrating trauma remain the strongest associations. LEVEL OF EVIDENCE: Prognostic/epidemiologic study, level III; Therapeutic study, level IV.
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Gerenciamento Clínico , Rim/lesões , Sociedades Médicas , Traumatologia , Sistema Urogenital/lesões , Ferimentos não Penetrantes/cirurgia , Ferimentos Penetrantes/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Tempo , Centros de Traumatologia , Índices de Gravidade do Trauma , Adulto JovemRESUMO
Immature dendritic cells (DCs) maintain a highly dynamic pool of recycling MHCII that promotes sampling of environmental antigens for presentation to T helper cells. However, the molecular basis of MHCII recycling and the cellular machinery that orchestrates MHCII trafficking are incompletely understood. Using a mouse model we show that WASH, an actin regulatory protein that facilitates retromer function, is essential for MHCII recycling and efficient priming of T helper cells. We further demonstrate that WASH deficiency results in impaired MHCII surface levels, recycling, and an accumulation of polyubiquitinated MHCII complexes, which are subsequently slated for premature lysosomal degradation. Consequently, conditional deletion of the Wash gene in DCs impairs priming of both conventional and autoimmune T helper cells in vivo and attenuates disease progression in a model of experimental autoimmune encephalitis (EAE). Thus, we identify a novel mechanism in which DCs employ the evolutionarily conserved WASH and retromer complex for MHCII recycling in order to regulate T helper cell priming.
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Células Dendríticas/fisiologia , Antígenos de Histocompatibilidade Classe II/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Sequência de Bases , Primers do DNA , Encefalomielite Autoimune Experimental/imunologia , Ensaio de Imunoadsorção Enzimática , Antígenos de Histocompatibilidade Classe II/metabolismo , Lisossomos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , UbiquitinaçãoRESUMO
WASH is an Arp2/3 activator of the Wiskott-Aldrich syndrome protein superfamily that functions during endosomal trafficking processes in collaboration with the retromer and sorting nexins, but its in vivo function has not been examined. To elucidate the physiological role of WASH in T cells, we generated a WASH conditional knockout (WASHout) mouse model. Using CD4(Cre) deletion, we found that thymocyte development and naive T cell activation are unaltered in the absence of WASH. Surprisingly, despite normal T cell receptor (TCR) signaling and interleukin-2 production, WASHout T cells demonstrate significantly reduced proliferative potential and fail to effectively induce experimental autoimmune encephalomyelitis. Interestingly, after activation, WASHout T cells fail to maintain surface levels of TCR, CD28, and LFA-1. Moreover, the levels of the glucose transporter, GLUT1, are also reduced compared to wild-type T cells. We further demonstrate that the loss of surface expression of these receptors in WASHout cells results from aberrant accumulation within the collapsed endosomal compartment, ultimately leading to degradation within the lysosome. Subsequently, activated WASHout T cells experience reduced glucose uptake and metabolic output. Thus, we found that WASH is a newly recognized regulator of TCR, CD28, LFA-1, and GLUT1 endosome-to-membrane recycling. Aberrant trafficking of these key T cell proteins may potentially lead to attenuated proliferation and effector function.
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Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/imunologia , Animais , Antígenos CD28/imunologia , Antígenos CD28/metabolismo , Antígenos CD4/genética , Antígenos CD4/imunologia , Proliferação de Células , Células Cultivadas , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Deleção de Genes , Transportador de Glucose Tipo 1/imunologia , Transportador de Glucose Tipo 1/metabolismo , Glicólise , Interleucina-2/imunologia , Ativação Linfocitária , Antígeno-1 Associado à Função Linfocitária/imunologia , Antígeno-1 Associado à Função Linfocitária/metabolismo , Camundongos , Camundongos Knockout , Transporte Proteico , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/metabolismo , Proteína da Síndrome de Wiskott-Aldrich/genética , Proteína da Síndrome de Wiskott-Aldrich/imunologiaRESUMO
OBJECTIVE: To determine whether there is a relationship between congenital nasolacrimal duct obstruction (CNLDO) and subsequent refractive error disorders in children. METHODS: The medical records of children 5 years and younger diagnosed as having CNLDO between January 1, 2000, and December 31, 2007, were retrospectively reviewed. RESULTS: Three hundred five consecutive children were diagnosed as having CNLDO at a median age of 12.3 months (range, 0.8 months to 4.8 years). Thirty children (9.8%) were diagnosed as having anisometropia with (n = 16) or without (n = 14) amblyopia at a median age of 19.2 months (range, 3.6 months to 7.4 years). Twenty-six of the 30 patients had hyperopic anisometropia; more severe hyperopia occurred in the eye with CNLDO in 23 patients (88.5%), 2 patients had more severe hyperopia in the fellow eye, and 1 patient had bilateral CNLDO. The median initial (P = .005) and final (P < .001) refractive error was significantly more hyperopic in those with both CNLDO and anisometropia compared with those with CNLDO alone. CONCLUSIONS: The development of anisometropia with or without amblyopia seems to be more frequent in children examined by an ophthalmologist for CNLDO compared with that reported for the general public. The laterality of more severe hyperopia and amblyopia is generally on the side of the previous dacryostenosis.