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Purpose: Today there exists only limited knowledge regarding the care of critically ill nontrauma (CINT) patients in the resuscitation room (RR) in Germany. The goal of this observational study was to describe the management of CINT patients in the RR of a nonuniversity emergency department. Methods: Data of adult nontrauma patients in the RR were prospectively collected in this study from 26 January 2019 to 18 May 2021 using the OBSERvE2 evaluation protocol. Results: In all, 213 patients were included in the study (age: 70⯱ 15 years, 55% male; admission to the RR by emergency medical service 93%). 28% were brought in after out-of-hospital cardiac arrest. Leading admission causes were C (47%) and B problems (39%). Diagnoses at the end of RR treatment were 30% pulmonary and 26% cardiovascular diseases without myocardial infarction as well as pulmonary embolism (8% and 5%, respectively). Measures performed were airway protection (20%), invasive (46%) and noninvasive ventilation (25%), cardiopulmonary resuscitation (13%), catecholamine therapy (34%), emergency ultrasound (62%). The initial treatment lasted for 41⯱ 22â¯min. Computed tomography was subsequently performed in 51%. On average 4-5 persons were involved in the treatment during the RR period. In total, 9% of the patients died during RR treatment and 40% in the hospital. Conclusion: Patients in a nonuniversity nontrauma RR are resource-intensive and have a high in-hospital lethality. RR care can be completed within 60â¯min. In order to achieve better comparability between patient populations of different locations, it is necessary to uniformly define admission criteria for the nontrauma resuscitation room.
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Auricular chondritis frequently occurs in relapsing polychondritis. In addition to the primary form of the disease up to 30% of cases of chondritis can be secondary, e.g. due to autoimmune diseases. We describe the case of a 62-year-old male patient with auricular chondritis as the first symptom of granulomatosis with polyangiitis. Anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis should always be considered in the differential diagnostics of relapsing polychondritis and antibody testing should be performed accordingly.
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Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Granulomatose com Poliangiite , Policondrite Recidivante , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Anticorpos Anticitoplasma de Neutrófilos , Diagnóstico Diferencial , Granulomatose com Poliangiite/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Policondrite Recidivante/diagnósticoRESUMO
BACKGROUND: The impact of isolated v-lesions on clinical outcome in biopsies with acute cellular rejection (ACR) is unclear. METHODS: Two hundred and sixty-five biopsies showing the highest ACR severity for each patient were recruited and classified into four groups: (i) acute interstitial rejection (AIR) I with minimal tubulointerstitial inflammation (TI), (ii) AIR II with intensive TI, (iii) acute vascular rejection (AVR) I with minimal TI, and (iv) AVR II with intensive TI. RESULTS: The complete reversal rates of AIR I and AIR II groups were marginally higher than AVR I and AVR II groups (p = 0.16). At eight yr of transplantation, the death-censored graft survival (DCGS) rate of AIR I group (93.3%) was significantly higher compared with the AVR I (72.7%) or AVR II (72.9%) group. AVR I group had a similar DCGS rate with AVR II group (72.7% vs. 74.1%), whereas AVR with v1-lesion showed significantly higher graft survival (GS) rate than those with v2-lesion (70.2% vs. 45.5%). The t-lesion of AIR and v-lesion of AVR group were associated with graft loss. CONCLUSION: The extent of TI is non-specifically associated with graft loss in biopsies with AVR; the higher grade v-lesion predicts the lower complete reversal rate and poorer long-term graft survival.
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Rejeição de Enxerto/patologia , Transplante de Rim , Rim/patologia , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Quimioterapia Combinada , Feminino , Seguimentos , Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico , Inflamação/patologia , Estimativa de Kaplan-Meier , Túbulos Renais/patologia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto JovemRESUMO
Inborn defects in nucleotide excision DNA repair (NER) can paradoxically result in elevated cancer incidence (xeroderma pigmentosum [XP]) or segmental progeria without cancer predisposition (Cockayne syndrome [CS] and trichothiodystrophy [TTD]). We report generation of a knockin mouse model for the combined disorder XPCS with a G602D-encoding mutation in the Xpd helicase gene. XPCS mice are the most skin cancer-prone NER model to date, and we postulate an unusual NER dysfunction that is likely responsible for this susceptibility. XPCS mice also displayed symptoms of segmental progeria, including cachexia and progressive loss of germinal epithelium. Like CS fibroblasts, XPCS and TTD fibroblasts from human and mouse showed evidence of defective repair of oxidative DNA lesions that may underlie these segmental progeroid symptoms.
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Síndrome de Cockayne/patologia , Progéria/patologia , Neoplasias Cutâneas/patologia , Proteína Grupo D do Xeroderma Pigmentoso/metabolismo , Xeroderma Pigmentoso/patologia , Animais , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Transformada , Síndrome de Cockayne/complicações , Síndrome de Cockayne/metabolismo , Reparo do DNA , Modelos Animais de Doenças , Suscetibilidade a Doenças , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Masculino , Camundongos , Camundongos Mutantes , Mutação , Papiloma/etiologia , Papiloma/metabolismo , Papiloma/patologia , Fenótipo , Progéria/complicações , Progéria/metabolismo , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/metabolismo , Xeroderma Pigmentoso/complicações , Xeroderma Pigmentoso/metabolismo , Proteína Grupo D do Xeroderma Pigmentoso/genéticaRESUMO
A 63-year old woman presented with dry necrotic areas on the distal and medial phalanges of her right index and middle finger caused by burns while smoking. Differential diagnostic considerations included occlusive arterial disease, vasculitis, endangiitis obliterans, peripheral embolisms and exposure to chemicals. The patient had the habit of smoking her cigarettes until the last possible drag, putting her skin in direct contact with the burning tobacco.
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Queimaduras/patologia , Traumatismos dos Dedos/patologia , Pele/lesões , Pele/patologia , Fumar/efeitos adversos , Produtos do Tabaco/efeitos adversos , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , NecroseRESUMO
Donor-specific HLA antibodies (DSA) have a negative impact on kidney graft survival. Therefore, we analyzed the occurrence of DSA and antibody-mediated rejection (AMR) in patients from two prospective randomized trials in our center. At 3-4.5 months posttransplant 127 patients were randomized to continue cyclosporine or converted to everolimus therapy. The presence of DSA was prospectively assessed using Luminex assays. AMR was defined according to the Banff 2009 classification. Antibody screening was available in 126 patients with a median follow-up of 1059 days. Seven out of 65 (10.8%) patients on cyclosporine developed DSA after a median of 991 days. In comparison, 14/61 patients (23.0%) randomized to everolimus developed DSA after 551 days (log-rank: p = 0.048). Eight patients on everolimus compared to two patients on cyclosporine developed AMR (log-rank: p = 0.036). Four of 10 patients with AMR-all in the everolimus group-lost their graft. A multivariate regression model revealed everolimus, >3 mismatches and living donor as significant risk factors for DSA. Acute rejection within the first year, >3 mismatches, everolimus and living donor were independent risk factors for AMR. This single center analysis demonstrates for the first time that everolimus-based immunosuppression is associated with an increased risk for the development of DSA and AMR.
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Ciclosporina/uso terapêutico , Rejeição de Enxerto/tratamento farmacológico , Antígenos HLA/imunologia , Imunossupressores/uso terapêutico , Isoanticorpos/efeitos adversos , Transplante de Rim/imunologia , Sirolimo/análogos & derivados , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Everolimo , Feminino , Seguimentos , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto/imunologia , Humanos , Isoanticorpos/sangue , Isoanticorpos/imunologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Sirolimo/uso terapêutico , Taxa de Sobrevida , Doadores de Tecidos , Adulto JovemRESUMO
For decades dacarbazine was the standard in the therapy for metastatic melanoma even though response rates were low. In recent years multiple pharmacological approaches have led to new therapy options including immune modulators like anti-CTLA4 antibodies and kinase inhibitors of the MAPK signaling pathway that showed better response rates and increased overall survival. However, since immune modulators lead only in a small subgroup of patients to long-term responses and kinase inhibitors lose their function due to development of resistance after several months, continuation of clinical studies is strongly required. Classical chemotherapeutic drugs will remain a basic part of the therapy especially as combinations of different treatment options have to be focused on in order to achieve better long-term survival rates.
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Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Fatores Imunológicos/uso terapêutico , Melanoma/tratamento farmacológico , Terapia de Alvo Molecular/tendências , Neoplasias Cutâneas/tratamento farmacológico , HumanosRESUMO
The development of a portfolio of SARS-CoV-2 vaccines to vaccinate the global population remains an urgent public health imperative. Here, we demonstrate the capacity of a subunit vaccine under clinical development, comprising the SARS-CoV-2 Spike protein receptor-binding domain displayed on a two-component protein nanoparticle (RBD-NP), to stimulate robust and durable neutralizing antibody (nAb) responses and protection against SARS-CoV-2 in non-human primates. We evaluated five different adjuvants combined with RBD-NP including Essai O/W 1849101, a squalene-in-water emulsion; AS03, an alpha-tocopherol-containing squalene-based oil-in-water emulsion used in pandemic influenza vaccines; AS37, a TLR-7 agonist adsorbed to Alum; CpG 1018-Alum (CpG-Alum), a TLR-9 agonist formulated in Alum; or Alum, the most widely used adjuvant. All five adjuvants induced substantial nAb and CD4 T cell responses after two consecutive immunizations. Durable nAb responses were evaluated for RBD-NP/AS03 immunization and the live-virus nAb response was durably maintained up to 154 days post-vaccination. AS03, CpG-Alum, AS37 and Alum groups conferred significant protection against SARS-CoV-2 infection in the pharynges, nares and in the bronchoalveolar lavage. The nAb titers were highly correlated with protection against infection. Furthermore, RBD-NP when used in conjunction with AS03 was as potent as the prefusion stabilized Spike immunogen, HexaPro. Taken together, these data highlight the efficacy of the RBD-NP formulated with clinically relevant adjuvants in promoting robust immunity against SARS-CoV-2 in non-human primates.
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This paper presents a new electrochemical method for the detection and characterisation of aqueous droplets in an organic carrier fluid (1,2-dichloroethane) formed in flow-focusing microfluidic devices. The devices consist of a conventional flow-focusing channel 250 microm wide and 250 microm deep cast out of poly(dimethylsiloxane) (PDMS) which is sealed onto a glass substrate containing a set of microelectrodes 100 microm long. Chronoamperometric analysis of a suitable electrolyte contained in the organic phase is presented for characterising the droplet frequency and size. This chronoamperometric method is then extended to a dual working electrode approach in order to determine the velocity of the droplet. Good agreement between experimental measurements and theory was observed.
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Microfluídica/métodos , Custos e Análise de Custo , Dimetilpolisiloxanos/química , Eletroquímica , Eletrônica , Vidro/química , Microeletrodos , Microfluídica/economia , Fenômenos ÓpticosRESUMO
The protein products of many dominant oncogenes are capable of inducing both cell proliferation and apoptosis. Recent experiments employing transgenic mice that express an ectopically regulatable myc gene or protein have begun to elucidate the role of the balance between proliferation and apoptosis in Myc-induced carcinogenesis. An outstanding feature of these experiments is the demonstration that the balance between oncogene-induced proliferation and apoptosis in a given tissue can be a critical determinant in the initiation and maintenance of the tumor.
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Apoptose/genética , Genes myc , Neoplasias/genética , Animais , Divisão Celular/genética , Diabetes Mellitus/genética , Diabetes Mellitus/patologia , Regulação da Expressão Gênica , Humanos , Ilhotas Pancreáticas/patologia , Linfoma/patologia , Camundongos , Camundongos Transgênicos , Neoplasias/patologia , Pele/citologiaRESUMO
BACKGROUND: Current evidence on steroid withdrawal following AB0-incompatible (AB0i) renal transplantation is low. We compared clinical outcomes of patients who agreed to late steroid withdrawal and patients who remained on steroid treatment. METHODS: Steroid withdrawal was carried out in 11 patients at ≥12 months after transplantation (group W). For comparison, we analyzed 19 patients who remained on triple immunosuppression including steroids (group M). Minimum follow-up was 24 months following transplantation and 12 months after steroid withdrawal. RESULTS: Baseline characteristics, including observation times, were not different between groups W and M. Graft survival was 100% in group W compared with 84% (16/19) in group M (P = .15). In group M, 1 patient experienced graft failure because of suspected antibody-mediated rejection (ABMR) following temporary cessation of mycophenolate treatment after a diagnosis of cryptococcal pneumonia. Two patients died with functioning graft because of sepsis. In group W, we observed 1 episode of ABMR following steroid withdrawal. At the end of follow-up, estimated glomerular filtration rates (eGFR) were 54 (19-91) versus 60 (15-85) mL/min/1.73 m2 in group W versus M, respectively (P = .67). CONCLUSIONS: Late steroid withdrawal following AB0i transplantation is feasible at a moderate risk of rejection. We recommend close monitoring of renal function and HLA antibodies during and after steroid withdrawal. On the other hand, the occurrence of severe infections causing death and graft loss in patients on triple maintenance immunosuppression including steroids should remind us to consider the overall immunosuppressive burden.
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Incompatibilidade de Grupos Sanguíneos/tratamento farmacológico , Terapia de Imunossupressão/métodos , Imunossupressores/administração & dosagem , Esteroides/administração & dosagem , Suspensão de Tratamento , Adulto , Feminino , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Rim/imunologia , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Fatores de TempoRESUMO
mHR23B encodes one of the two mammalian homologs of Saccharomyces cerevisiae RAD23, a ubiquitin-like fusion protein involved in nucleotide excision repair (NER). Part of mHR23B is complexed with the XPC protein, and this heterodimer functions as the main damage detector and initiator of global genome NER. While XPC defects exist in humans and mice, mutations for mHR23A and mHR23B are not known. Here, we present a mouse model for mHR23B. Unlike XPC-deficient cells, mHR23B(-/-) mouse embryonic fibroblasts are not UV sensitive and retain the repair characteristics of wild-type cells. In agreement with the results of in vitro repair studies, this indicates that mHR23A can functionally replace mHR23B in NER. Unexpectedly, mHR23B(-/-) mice show impaired embryonic development and a high rate (90%) of intrauterine or neonatal death. Surviving animals display a variety of abnormalities, including retarded growth, facial dysmorphology, and male sterility. Such abnormalities are not observed in XPC and other NER-deficient mouse mutants and point to a separate function of mHR23B in development. This function may involve regulation of protein stability via the ubiquitin/proteasome pathway and is not or only in part compensated for by mHR23A.
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Reparo do DNA , Proteínas de Ligação a DNA/genética , Desenvolvimento Embrionário e Fetal , Proteínas Fúngicas/genética , Infertilidade Masculina/genética , Proteínas de Saccharomyces cerevisiae , Animais , Peso Corporal , Linhagem Celular , Sobrevivência Celular , Anormalidades Craniofaciais/embriologia , Anormalidades Craniofaciais/genética , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/fisiologia , Relação Dose-Resposta à Radiação , Olho/patologia , Feminino , Fertilidade , Fibroblastos/fisiologia , Fibroblastos/efeitos da radiação , Proteínas Fúngicas/química , Proteínas Fúngicas/fisiologia , Marcação de Genes , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Tamanho do Órgão , Placenta/patologia , Espermatogênese , Testículo/patologia , Testículo/fisiologia , Testículo/fisiopatologia , Raios UltravioletaRESUMO
AIMS: Numerous patients suffer from recurrence after resection of liver metastases from colorectal cancer. Recurrence is frequently restricted to the liver and repeat liver resection may offer a curative option in these patients. This study was conducted to clarify safety and effectiveness of this treatment and to identify prognostic factors of a favourable outcome after repeat hepatectomy. METHODS: Between January 1988 and March 2006 in our institution 811 patients underwent 841 liver resections for metastases from colorectal cancer. Among these, 94 patients underwent a repeat hepatectomy. Patients were identified from a prospective database and retrospectively reviewed. Results of different time periods were assessed and prognostic factors for a favourable outcome were determined. RESULTS: The perioperative morbidity and mortality was 24% (23 of 94) and 3% (3 of 94), respectively. The one-, three-, five- and ten-year survival for all patients in this series was 89%, 55%, 38% and 23%, respectively. In the univariate analysis, pT-stage of the primary, diameter of the largest metastases, surgical radicality, period of resection and distribution of metastases showed statistically significant influence on survival. The multivariate analysis revealed only pT-stage of the primary tumour, surgical radicality and period of resection as independent prognostic factors. CONCLUSIONS: Repeat hepatectomy is a safe and effective treatment for recurrent liver metastases from colorectal cancer. Perioperative risk and long-term survival were similar when compared to the results obtained during the initial resection. Achieving a curative resection is the most relevant prognostic factor for a favourable prognosis after repeat liver resection.
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Neoplasias Colorretais/patologia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Idoso , Distribuição de Qui-Quadrado , Feminino , Hepatectomia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Reoperação , Estudos Retrospectivos , Estatísticas não Paramétricas , Taxa de SobrevidaRESUMO
BACKGROUND: We report a case of severe upper airway obstruction due to a retropharyngeal hematoma that presented nearly one day after a precipitating traumatic injury. Retropharyngeal hematomas are rare, but may cause life-threatening airway compromise. CASE PRESENTATION: A 50 year-old man developed severe dyspnea with oropharyngeal airway compression due to retropharyngeal hematoma 20 hours after presenting to the emergency department. The patient also had a fractured first cervical vertebra and was diagnosed with a left brachial plexopathy. The patient underwent emergent awake fiberoptic endotracheal intubation to provide a definitive airway. CONCLUSION: Retropharyngeal hematoma with life-threatening airway compromise can develop hours or days after a precipitating injury. Clinicians should be alert to the potential for this delayed airway collapse, and should also be prepared to rapidly secure the airway in this patient population likely to have concomitant cervical spinal or head injuries.
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OBJECTIVE: The new GH receptor antagonist pegvisomant is the most effective medical therapy to normalize IGF-I levels in patients with acromegaly. Based on currently available data pegvisomant is well tolerated; however, treatment-induced elevation of transaminases has been reported and led to the necessity for drug discontinuation in some patients in the pivotal studies. The aim of this study was to evaluate and characterize the prevalence of elevated transaminases and to describe in detail the findings in a single case who required drug discontinuation because of elevation of transaminases which emerged during treatment and who underwent liver biopsy. DESIGN AND METHODS: Retrospective safety analyses were carried out on 142 patients with acromegaly receiving pegvisomant treatment in Germany between March 2003 and the end of 2004. Of these patients, 123 were documented in a post-marketing surveillance study, one case of elevated transaminases was reported spontaneously and the other patients were treated in a clinical study. RESULTS: Mean treatment duration with pegvisomant in the ongoing observational study at the end of 2004 was 28.3 +/- 19.9 (S.D.) weeks. Twelve out of the 142 patients had elevated transaminases above three times the upper limit of normal, likely caused by biliary obstruction in five of the patients. All patients but one affected by elevated transaminases had been previously treated with somatostatin analogues. In six out of 142 (4%) of patients, pegvisomant was permanently withdrawn because of elevated transaminases. The same number of patients showed a transient increase of transaminases with either spontaneous remission without dose modification (n = 4) or no re-increase of transaminases after temporary discontinuation and re-exposure (n = 2). The liver biopsy of one patient who was permanently withdrawn showed a chronic mild hepatitis with a mixed portal inflammation including eosinophilic granulocytes. CONCLUSIONS: Liver function tests should be regularly followed on pegvisomant treatment. Biliary complications, which may arise from restitution of normal gall bladder motility after cessation of somatostatin analogue treatment, need to be differentiated from pegvisomant-induced abnormalities. The histological pattern of the liver biopsy performed in one of the patients showed a mild chronic active hepatitis. The lack of dose dependency and rather low frequency of elevated transaminases in those cases where a biliary disorder was excluded render this reaction an idiosyncratic drug toxicity.
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Acromegalia/tratamento farmacológico , Acromegalia/enzimologia , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Hormônio do Crescimento Humano/análogos & derivados , Fator de Crescimento Insulin-Like I/metabolismo , Adulto , Feminino , Hepatite Crônica/patologia , Histocitoquímica , Hormônio do Crescimento Humano/efeitos adversos , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Masculino , Receptores da Somatotropina/antagonistas & inibidores , Estudos RetrospectivosRESUMO
INTRODUCTION: In small bowel disease such as M. Crohn, the intestinal absorption of oxalate is increased. Severe calcium oxalate deposition in multiple organs as consequence of enteric hyperoxaluria may lead to severe organ dysfunction and chronic renal failure. The management of hemodialyzed patients with short bowel syndrome may be associated with vascular access problems and oxalate infiltration of the bone marrow leading to pancytopenia. Although the risk of recurrence of the disease is very high after renal transplantation, it may be the ultimate therapeutic alternative in secondary hyperoxaluria. CASE: Here, we report a patient with enteric oxalosis due to Crohn's disease. He developed end-stage renal disease, erythropoietin-resistant anemia, oxalate infiltration of the bone marrow and severe vascular access problems. Following high-urgency kidney transplantation, daily hemodiafiltration of 3 hours was performed for 2 weeks to increase oxalate clearance. Despite tubular and interstitial deposition of oxalate in the renal transplant, the patient did not require further hemodialysis and the hematocrit levels normalized. DISCUSSION: Early treatment of hyperoxaluria due to short bowel syndrome is essential to prevent renal impairment. Declining renal function leads to a further increase in oxalate accumulation and consecutive oxalate deposition in the bone marrow or in the vascular wall. If alternative treatments such as special diet or daily hemodialysis are insufficient, kidney transplantation may be a therapeutic alternative in severe cases of enteric oxalosis despite a possible recurrence of the disease.
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Anemia/etiologia , Hiperoxalúria/cirurgia , Transplante de Rim , Adulto , Biópsia , Medula Óssea/patologia , Doença de Crohn/complicações , Seguimentos , Humanos , Hiperoxalúria/complicações , Hiperoxalúria/patologia , Masculino , Remissão Espontânea , Índice de Gravidade de DoençaRESUMO
To investigate Mad1 function in vivo, transgenic mice were generated that express a Mad1 transgene in T lineage cells under the control of the proximal lck promoter. Thymus size in lck-Mad1 transgenic mice is drastically reduced although representation of the various thymocyte sub populations appears normal. To investigate more closely any effects of Mad1 expression on thymocytes, we examined thymic selection using MHC class I-restricted H-Y-TCR transgenic mice. Mad1 expression in vivo reduces the efficiency of positive selection. Furthermore, thymocytes and splenic T cells from lck-Mad1 transgenic mice display a profound proliferative defect in response to activation with either PMA/Ionomycin or immobilized anti-CD3/CD28 antibody. This proliferative defect is not reversed by addition of exogenous IL-2 and is p53-independent. The growth inhibition caused by Mad1 is overcome by expression of active c-Myc.
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Ativação Linfocitária/efeitos dos fármacos , Mitógenos/farmacologia , Fosfoproteínas/biossíntese , Proteínas Repressoras/biossíntese , Linfócitos T/imunologia , Timo/imunologia , Animais , Antígenos CD/fisiologia , Western Blotting , Proteínas de Ciclo Celular , Primers do DNA/química , Feminino , Genes myc/fisiologia , Antígeno H-Y/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Técnicas Imunoenzimáticas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Proteínas Nucleares , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fase S/efeitos dos fármacos , Baço/imunologia , Timo/patologia , Proteína Supressora de Tumor p53/metabolismoRESUMO
In order to study the effect of c-Myc activation in T lymphocytes in vivo, we generated transgenic mice that express a 4-hydroxytamoxifen (4-OHT)-dependent switchable c-myc oncoprotein under the control of the proximal lck promoter. Activation of c-MycER causes no obvious alteration in T cell ontogeny. However, using MHC class I restricted H-Y-TCR transgenic mice, we found that c-Myc activation in vivo enhances the efficiency of positive selection. Moreover, splenic T cells derived from lck-c-mycER transgenic mice in which c-Myc had been activated exhibited increased proliferation in vitro in response to activation with anti-CD3/CD28 antibody. Activation of c-MycER also promotes apoptosis in thymocytes in vitro.
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Apoptose , Regulação Neoplásica da Expressão Gênica , Genes myc , Linfócitos T/metabolismo , Animais , Diferenciação Celular , Divisão Celular , Camundongos , Camundongos Transgênicos , Linfócitos T/fisiologia , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacologia , Timo/citologiaRESUMO
Activation of Myc triggers a rapid induction of cyclin E/cdk2 kinase activity and degradation of p27. Overt degradation of p27 is preceded by a specific dissociation of p27 from cyclin E/cdk2, but not from cyclin D/cdk4 complexes. We now show that cyclin E/cdk2 phosphorylates p27 at a carboxy-terminal threonine residue (T187) in vitro; mutation of this residue to valine stabilises cyclin E/cdk2 complexes. This reaction is not significantly inhibited by high concentrations of p27, suggesting that cdk2 bound to p27 is catalytically active. In vivo, p27 bound to cyclins E and A, but not to D-type cyclins is phosphorylated. Myc-induced release of p27 from cdk2 requires cdk2 kinase activity and is delayed in a T187V mutant of p27. After induction of Myc, p27 phosphorylated at threonine 187 transiently accumulates in a non cdk2 bound form. Our data suggest a mechanism in which p27 is released from cyclin E/cdk2 upon phosphorylation; in Myc-transformed cells, release is efficient as phosphorylated p27 is transiently bound in a non-cdk2 containing complex and subsequently degraded.
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Quinases relacionadas a CDC2 e CDC28 , Proteínas de Ciclo Celular , Ciclina E/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Genes myc/fisiologia , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Supressoras de Tumor , Animais , Células Cultivadas , Quinase 2 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p27 , Camundongos , Fosforilação , CoelhosRESUMO
PURPOSE: The differential diagnosis of early gastric mucosa-associated lymphatic tissue (MALT) lymphoma based on Helicobacter pylori gastritis may be difficult when lymphoepithelial lesions are not detected. The aim of the present study was to investigate the question whether the polymerase chain reaction (PCR) or cure of H pylori infection may be of help in this respect. PATIENTS AND METHODS: Twenty patients with suspected low-grade gastric MALT lymphomas were treated in a double-blinded, randomized, crossover trial with 2,250 mg of either amoxicillin or placebo, both in combination with omeprazole, for 14 days with the aim to cure H pylori infection. PCR was performed using primers specific for the CDR3 region to detect monoclonal B cells. RESULTS: In five of 20 patients, MALT lymphomas were finally diagnosed. Three of these five patients went into complete remission, while two were referred to surgery. In the 15 patients with gastritis, complete regression was observed in all cases. With respect to PCR, monoclonal bands were detected in all four of the analyzed lymphoma patients before histology showed lymphoma. In addition, monoclonal bands were found in three patients with gastritis. In the patients with gastritis and monoclonal PCR, complete regression took longer as compared with the remaining 12 patients with polyclonal PCR and gastritis (P = .0209). Successful H pylori eradication was associated with earlier diagnosis of the MALT lymphoma (P = .0237). CONCLUSION: CDR3-PCR may be of help in the differential diagnosis of early gastric MALT lymphoma. Furthermore, H pylori eradication may lead to earlier diagnosis.