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1.
Elife ; 112022 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-36341713

RESUMEN

JC polyomavirus (JCPyV) causes progressive multifocal leukoencephalopathy (PML), a life-threatening brain disease in immunocompromised patients. Inherited and acquired T cell deficiencies are associated with PML. The incidence of PML is increasing with the introduction of new immunomodulatory agents, several of which target T cells or B cells. PML patients often carry mutations in the JCPyV VP1 capsid protein, which confer resistance to neutralizing VP1 antibodies (Ab). Polyomaviruses (PyV) are tightly species-specific; the absence of tractable animal models has handicapped understanding PyV pathogenesis. Using mouse polyomavirus (MuPyV), we found that T cell deficiency during persistent infection, in the setting of monospecific VP1 Ab, was required for outgrowth of VP1 Ab-escape viral variants. CD4 T cells were primarily responsible for limiting polyomavirus infection in the kidney, a major reservoir of persistent infection by both JCPyV and MuPyV, and checking emergence of these mutant viruses. T cells also provided a second line of defense by controlling the outgrowth of VP1 mutant viruses that evaded Ab neutralization. A virus with two capsid mutations, one conferring Ab-escape yet impaired infectivity and a second compensatory mutation, yielded a highly neurovirulent variant. These findings link T cell deficiency and evolution of Ab-escape polyomavirus VP1 variants with neuropathogenicity.


Asunto(s)
Síndromes de Inmunodeficiencia , Virus JC , Leucoencefalopatía Multifocal Progresiva , Poliomavirus , Animales , Ratones , Poliomavirus/genética , Virus JC/genética , Anticuerpos Neutralizantes
3.
Pediatr Transplant ; 26(2): e14173, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34687570

RESUMEN

BACKGROUND: There is a scarcity of long-term data on steroid-free immunosuppression using alemtuzumab in pediatric kidney transplantation (KTx). This study examines long-term outcomes with alemtuzumab without steroid maintenance therapy in pediatric KTx. METHODS: From July 2005 to June 2015, 71 pediatric KTx recipients received alemtuzumab without steroid maintenance. They were followed from 4.1 to 14.1 years post KTx. RESULTS: Patient survival: One child expired with a functioning graft from post-transplant lymphoproliferative disorder (PTLD). Patient survival was 98.6%. Graft survival: Eighteen grafts were lost (16 from chronic rejection). Graft survival at 5 and 10 years was 92.3% and 61.3%, respectively. Rejection: Twenty-three (32.4%) patients were free from T-cell-mediated rejection (TCMR), 16 (22.5%) had >3 episodes. Sixteen (22.5%) were treated for antibody-mediated rejection (AMR). Infection: Twenty-three children developed Epstein-Barr virus (EBV), 5 developed cytomegalovirus (CMV), and 20 developed BK virus infection. Four (5.6%) developed PTLD. Twenty-two (31.0%) required treatment for neutropenia. Growth parameters: Mean height and weight increased by 0.56 and 0.69 SDS (standard deviation score), respectively. Body mass index increased by 5.1 kg/m2 at 10 years. Less than 40% required antihypertensive medications at all-time points. CONCLUSION: Alemtuzumab, without corticosteroid maintenance, offers 98.6% patient survival at 14 years with five and 10-year graft survival of 92.3% and 61.3%, respectively. TCMR and AMR requiring treatment were 67.4% and 22.5%, respectively. CMV, EBV, and BK viremia rates were 7.0%, 32.4%, and 28.2%, respectively. Thirty-one percent were treated for neutropenia; 5.6% developed PTLD. There were improvements in growth parameters and blood pressure.


Asunto(s)
Alemtuzumab/uso terapéutico , Terapia de Inmunosupresión/métodos , Trasplante de Riñón , Adolescente , Niño , Preescolar , Infecciones por Citomegalovirus/etiología , Infecciones por Virus de Epstein-Barr/etiología , Femenino , Rechazo de Injerto , Humanos , Inmunosupresores/administración & dosificación , Lactante , Trastornos Linfoproliferativos/etiología , Masculino , Ácido Micofenólico/administración & dosificación , Tacrolimus/administración & dosificación
4.
Endosc Int Open ; 7(2): E186-E188, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30705951

RESUMEN

Background and study aims Endoscopic ultrasound (EUS)-guided chemoablation with ethanol lavage, followed by infusion with paclitaxel, has been found to be effective for treatment of mucinous pancreatic cysts. However, there are notable adverse events (AEs) associated with ethanol and its undesirable inflammatory effects on local tissue and vessels. The recent ChARM trial demonstrated that removing ethanol from the cyst ablation process resulted in equivalent efficacy while significantly reducing associated AEs. Encouraged by these results, we speculated that alcohol-free chemoablation can be applied to treatment of solid tumors, as described in our case with a patient with severe and symptomatic recurrent hypoglycemia in the setting of multifocal insulinomas. As a result, the patient saw a significant reduction in symptoms. EUS-guided alcohol-free chemoablation may represent a new alternative to previously established therapies that will ultimately reduce risk of AEs.

5.
Diagn Cytopathol ; 44(2): 113-8, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26663577

RESUMEN

BACKGROUND: The Bethesda system for reporting thyroid cytopathology was proposed to provide a clinically relevant framework for interpretations to improve interobserver agreement. Limited data is available regarding the level of interobserver agreement between groups of cytotechnologists (CTs) and cytopathologists (CPs) examining the same thyroid fine needle aspirate (FNA) samples. METHODS: Retrospective review of 1,229 thyroid FNAs from 976 patients between 03/2010 and 08/2012 was performed. FNAs received preliminary evaluation by a CT followed by final interpretation by a CP. We calculated Cohen's Kappa coefficient to measure agreement between CTs and CPs, and analyzed levels of discrepancy using delta analysis. RESULTS: Overall Kappa between CTs and CPs was 0.79 (95%CI: 0.76-0.83). Kappa values were higher for the nondiagnostic (0.89), benign (0.83), and malignant (0.91) categories than for other categories. Overall Kappa did not show a trend over time, and inversely correlated with the percentage of intermediate grade lesions (coefficient of -0.8; P < 0.01). CTs overcalled more cases (n = 71) than undercalled (n = 29) (P < 0.001), as compared to CPs, with a Δ1 ratio of 2.2 and Δ2 ratio of 3.5. Most two-level discrepancies were related to follicular lesions (19/21) (P = 0.0002). Differences in sample adequacy assessment occurred in 2% of cases. CONCLUSION: Overall, there was a high level of interpretative agreement between CTs and CPs, which remained stable over time, including judgments regarding specimen adequacy. Agreement was most robust for the benign and malignant categories. Our data supports the current practice of allowing CTs to perform on-site adequacy evaluation of thyroid FNAs.


Asunto(s)
Nódulo Tiroideo/patología , Biopsia con Aguja Fina/normas , Humanos , Clasificación del Tumor/normas , Variaciones Dependientes del Observador , Nódulo Tiroideo/clasificación
6.
Hum Immunol ; 76(8): 587-90, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26382246

RESUMEN

The majority of de novo donor specific HLA antibodies (DSAs) in transplant patients are directed to HLA-DQ antigens, which consist of a heterodimer of alpha and beta chains. Although a heterodimer can theoretically be cis- or trans-encoded, the sensitizing forms generally appear to be forms. DSA to DQ trans-heterodimer has never been reported. We reviewed 360 post-kidney transplant recipients (transplant: 2002-2013; follow-up: 5.6±3.3years). DQ DSA was detected in 46 of 57 patients who developed DSA. DSA specificity was consistent with donor mismatched DQ trans-heterodimers in three patients: DQ2.5 (DQB1*02, DQA1*05), DQ2.3 (DQB1*02, DQA1*03), and DQ4.3 (DQB1*04, DQA1*03). Two of them eventually lost grafts (2 and 5years later) with allograft nephropathy. In conclusion, post-transplant patients may develop DSA to donor DQ trans-heterodimers. Further studies are warranted to determine the clinical significance of such DSAs.


Asunto(s)
Especificidad de Anticuerpos/inmunología , Antígenos HLA-DQ/inmunología , Isoanticuerpos/inmunología , Adolescente , Adulto , Anciano , Alelos , Niño , Preescolar , Femenino , Rechazo de Injerto/genética , Rechazo de Injerto/inmunología , Supervivencia de Injerto/genética , Supervivencia de Injerto/inmunología , Antígenos HLA/química , Antígenos HLA/genética , Antígenos HLA/inmunología , Antígenos HLA-DQ/química , Antígenos HLA-DQ/genética , Humanos , Trasplante de Riñón , Masculino , Persona de Mediana Edad , Evaluación del Resultado de la Atención al Paciente , Multimerización de Proteína , Estudios Retrospectivos , Donantes de Tejidos , Adulto Joven
7.
Rare Tumors ; 7(4): 6010, 2015 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-26788277

RESUMEN

Phyllodes tumor is an uncommon breast lesion with characteristic histologic appearance when examined by hematoxylin and eosin staining: leaf-like fronds projecting into cystic spaces on low-power microscopy, and biphasic (epithelial and stromal) components on high-power microscopy. We report a rare primary case of this tumor arising within the vulva. A 34-year old African American female presented with a 3 cm slow-growing vulvar mass initially thought to be an inclusion cyst. The lesion was excised and histologic examination demonstrated this lesion to be a rare case of benign phyllodes tumor with morphologic features similar to those arising from breast tissue. Patient received no further treatment and did not exhibit any recurrence or metastasis. Nearly two years after excision, the patient died due to an unrelated medical cause. This rare tumor should be considered in the differential diagnosis for women presenting with a slow-growing vulvar mass.

8.
Comp Med ; 63(4): 338-41, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24209969

RESUMEN

An 8-mo-old female transgenic adenocarcinoma of the mouse prostate (C57BL/6-Tg(TRAMP)8247Ng/J) mouse presented with abdominal distention, lethargy, and serosanguineous vaginal discharge. A large primary renal tumor with metastases to lung and liver was present at necropsy. The tumor was composed of poorly differentiated and crowded epithelial cells forming ducts, acini, and cribriform patterns, with comedonecrosis and frequent bizarre mitoses. Immunohistochemistry revealed that neoplastic cells expressed nuclear SV40 T antigen, confirming aberrant expression of the transgene. In addition, cells were positive for pancytokeratin and negative for synaptophysin and estrogen and progesterone receptors. This report details the first transgene-induced tumor in a female TRAMP mouse.


Asunto(s)
Adenocarcinoma/veterinaria , Carcinoma/veterinaria , Neoplasias Renales/veterinaria , Neoplasias de la Próstata/veterinaria , Enfermedades de los Roedores/patología , Adenocarcinoma/complicaciones , Adenocarcinoma/genética , Animales , Carcinoma/complicaciones , Carcinoma/genética , Carcinoma/patología , Modelos Animales de Enfermedad , Femenino , Neoplasias Renales/complicaciones , Neoplasias Renales/genética , Neoplasias Renales/patología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/veterinaria , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/veterinaria , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neoplasias de la Próstata/complicaciones , Neoplasias de la Próstata/genética , Enfermedades de los Roedores/genética
9.
Int Urol Nephrol ; 45(6): 1801-4, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23001610

RESUMEN

Minimal change disease is the most common glomerular disease affecting children; its prevalence among adults, however, is eclipsed by other glomerular pathologies. Each of these diseases has a number of classic associations, such as membranoproliferative glomerulonephritis with hepatitis C. We report the case of a middle-aged African-American male who presented with the nephrotic syndrome and acute renal failure and was concomitantly diagnosed with a new hepatitis C infection. He also had a history of urethral strictures with potential reflux nephropathy, which--in combination with his African-American race--also made focal segmental glomerulosclerosis a diagnostic possibility. Full laboratory evaluation did not distinguish the cause of his massive proteinuria; subsequent renal biopsy ultimately revealed minimal change disease. A full course of high-dose steroids eventually reduced his proteinuria, after which his renal failure resolved as well without need for hemodialysis.


Asunto(s)
Hepatitis C Crónica/complicaciones , Nefrosis Lipoidea/complicaciones , Lesión Renal Aguda/etiología , Hepatitis C Crónica/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Nefrosis Lipoidea/tratamiento farmacológico , Nefrosis Lipoidea/patología
10.
Med Teach ; 34(10): 783-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22816980

RESUMEN

Evaluation of undergraduate medical education programs is necessary to meet accreditation standards; however, implementation and maintenance of an adequate evaluation process is challenging. A curriculum evaluation committee (CEC) was established at the Penn State University College of Medicine in 2000 to complement the already established activities of the Office of the Vice Dean for Medical Education and the Committee on Undergraduate Medical Education. Herein, we describe the methodology used by the CEC at our academic medical center and outcomes attributable to the curriculum evaluation process that was enacted. Strengths of our process include ongoing, regular assessments that guarantee a course is reviewed at least every two years and a feedback loop whereby course directors are held accountable for implementing changes when necessary. Our evaluative process has proven effective, sustainable, and has identified additional areas for curricular improvements.


Asunto(s)
Curriculum , Educación de Pregrado en Medicina , Evaluación de Programas y Proyectos de Salud/métodos , Pennsylvania
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