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2.
Clin Exp Immunol ; 181(3): 451-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25739813

RESUMO

HIV-infected children are less capable of mounting and maintaining protective humoral responses to vaccination against measles compared to HIV-uninfected children. This poses a public health challenge in countries with high HIV burdens. Administration of anti-retroviral therapy (ART) and revaccinating children against measles is one approach to increase measles immunity in HIV-infected children, yet it is not effective in all cases. Immune anergy and activation during HIV infection are factors that could influence responses to measles revaccination. We utilized a flow cytometry-based approach to examine whether T cell anergy and activation were associated with the maintenance of measles-specific immunoglobulin (Ig)G antibodies generated in response to measles revaccination in a cohort of HIV-infected children on ART in Nairobi, Kenya. Children who sustained measles-specific IgG for at least 1 year after revaccination displayed significantly lower programmed cell death 1 (PD-1) surface expression on CD8(+) T cells on a per-cell basis and exhibited less activated CD4(+) T cells compared to those unable to maintain detectable measles-specific antibodies. Children in both groups were similar in age and sex, CD4(+) T cell frequency, duration of ART treatment and HIV viral load at enrolment. These data suggest that aberrant T cell anergy and activation are associated with the impaired ability to sustain an antibody response to measles revaccination in HIV-infected children on ART.


Assuntos
Formação de Anticorpos/imunologia , Infecções por HIV/imunologia , Sarampo/imunologia , Linfócitos T/imunologia , Anticorpos Antivirais/imunologia , Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , Criança , Pré-Escolar , Anergia Clonal/imunologia , Feminino , Citometria de Fluxo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Imunização Secundária/métodos , Imunoglobulina G/imunologia , Quênia , Ativação Linfocitária/imunologia , Masculino , Sarampo/prevenção & controle , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Carga Viral/imunologia
3.
Chirurgia (Bucur) ; 104(2): 187-94, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19499662

RESUMO

BACKGROUND: Laparoscopic esophagectomy is technically difficult especially during dissection in the upper mediastinum. This limitation may be surpassed with the help of mediastinoscopy or of the recently introduced robotic surgical systems. The aim of the present study was to evaluate in an experimental porcine model the feasibility of the combined laparoscopic and mediastinoscopic transhiatal esophagectomy technique and to compare it with the robotic-assisted transhiatal and conventional approaches. MATERIALS AND METHODS: Transhiatal esophagectomy was performed in Landrace pigs under general anesthesia using three different techniques: Group A (n = 9): combined laparoscopic and mediastinoscopic, group B (n = 4): robotic-assisted and group C (n = 8): conventional "open". The feasibility, difficulty and accuracy of the procedure along with operative time, blood loss, intraoperative incidents and overall satisfaction of the surgical team were assessed for each technique. RESULTS: Operations in group A were feasible and reproducible. Although the procedure was technically difficult, the constant view on the operative field was highly appreciated by the operative team and facilitated an accurate and safe dissection. The main intraoperative complications were related to the side-effects of tension pneumothorax accompanying pleural injuries. In group B the features of the robotic system reduced the difficulty of dissection and obviated the need for mediastinoscopy. Operations in group C were quick and almost incident-free, facilitated also by the particularities of the animal model that could not reproduce identically the clinical situation. CONCLUSIONS: The combined laparoscopic and mediastinoscopic esophagectomy technique is feasible and offers certain advantages over the open approach while the robotic-assisted approach is an emerging less difficult alternative. Further studies are required to establish whether the advantages of minimally-invasive approach compensate for the increased technical difficulty and prolonged operative time.


Assuntos
Esofagectomia/instrumentação , Esofagectomia/métodos , Laparoscopia/métodos , Mediastinoscopia/métodos , Robótica , Animais , Modelos Animais de Doenças , Esofagectomia/efeitos adversos , Estudos de Viabilidade , Pneumotórax/etiologia , Cirurgia Assistida por Computador , Sus scrofa , Suínos
4.
Eur J Surg Oncol ; 35(9): 986-93, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19138832

RESUMO

AIM: To evaluate local control for long-term prognosis in retroperitoneal soft-tissue sarcoma (primary tumors (PT) and local recurrence (LR)). METHODS: A total of 110 patients underwent surgery between 1988 and 2002. Prospectively gathered clinicopathological data were analyzed. Kaplan-Meier estimations and Cox regression analyses were performed. RESULTS: Resectability was 90%, being comparable for PT (n=71) and LR (n=39). Morbidity, mortality, blood loss, and operation time did not differ for PT or LR (24% vs. 31%, p=0.41; 7.0% vs. 5.1%, p=1.0; 1000 ml vs. 1500 ml, p=0.17; 240 min vs. 255 min, p=0.13). Hospitalization was comparable in both groups (median, 12 days (PT) and 13 days (LR)). Follow-up was 89 months (median, IQR 37-112 months). Local 3- and 5-year control rates after complete resection of PT were 66% and 59% (19% and 9% for LR, p<0.001). The mean number of operations were 1.4 for PT and 2.4 for LR (p=0.0047). The 5-year survival rates after complete resection were 51% for PT and 43% for LR (p=0.39). The 5-year survival rates were 65%, 4%, and 0% for complete resection, incomplete resection, and exploration, respectively (p<0.001). Multivariate analysis showed high-grade and blood loss with a poor prognosis. CONCLUSIONS: Comparable resectability rates and perioperative outcome were observed for surgery of PT and LR. Consequent reoperation leads to respectable long-term survival rates after resection of LR. The prognosis in retroperitoneal sarcomas varies significantly according to resectability, grade and blood loss.


Assuntos
Recidiva Local de Neoplasia/cirurgia , Neoplasias Retroperitoneais/cirurgia , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/cirurgia , Adulto , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia/patologia , Modelos de Riscos Proporcionais , Neoplasias Retroperitoneais/patologia , Sarcoma/patologia , Neoplasias de Tecidos Moles/patologia , Análise de Sobrevida , Resultado do Tratamento
5.
J Pathol ; 213(4): 441-52, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17935147

RESUMO

Alcohol exposure is known to sensitize acinar cells to various insults but the pathophysiological mechanisms of alcoholic pancreatitis remain unknown. Alcohol abuse has been shown to mediate an anti-inflammatory response and periods of immune suppression seem to be associated with organ injury and mortality. The purpose of this study was to determine the mechanisms by which alcohol exerts transcriptional activities in the rat pancreas and how alcohol alters the inflammatory response. Using the Lieber-DeCarli alcohol/control diet, rats that were fed with alcohol over 14 weeks demonstrated a decrease of inflammatory cells in pancreatic tissue compared to controls. The anti-inflammatory effects of alcohol were confirmed by decreased expression of pro-inflammatory cytokines including TNFalpha, IL-1beta, IL-18, TGFbeta, and MCP-1. In addition, alcohol significantly increased the activity of PPARgamma, which is a known anti-inflammatory transcription factor, while pro-inflammatory factors including AP-2 and EGR-1 were significantly suppressed. NFkappaB binding showed a tendency towards a reduction. Electron microscopy studies revealed enlarged and injured mitochondria and lysosomes, accompanied by peri-cellular fibrosis. Furthermore, alcohol exposure increased the activities of trypsin and cathepsin B, both known to be critical in initiating acinar cell injury and pancreatitis. Despite the known alcohol-mediated acinar cell and mitochondrial injury, the mitochondrial-mediated apoptotic pathway was attenuated. These data demonstrate that the pancreas exposed to alcohol maintains an anti-inflammatory state by activating PPARgamma. Intracellular mitochondrial and lysosomal damage after chronic alcohol exposure induces premature activation of digestive enzymes and establishment of peri-cellular fibrosis in the absence of inflammation.


Assuntos
Etanol/toxicidade , Tolerância Imunológica/efeitos dos fármacos , PPAR gama/fisiologia , Pâncreas/efeitos dos fármacos , Pancreatite Alcoólica/imunologia , Animais , Apoptose/efeitos dos fármacos , Catepsina B/metabolismo , Citocinas/biossíntese , Citocinas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/ultraestrutura , Masculino , Microscopia Eletrônica , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/ultraestrutura , PPAR gama/efeitos dos fármacos , Pâncreas/imunologia , Pâncreas/metabolismo , Pâncreas/ultraestrutura , Pancreatite Alcoólica/metabolismo , Pancreatite Alcoólica/patologia , Peroxidase/metabolismo , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Tripsina/metabolismo
7.
Swiss Surg ; 9(4): 193-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12974179

RESUMO

BACKGROUND: There is accumulating evidence, both quantitative and qualitative, that pelvic irradiation affects anorectal function. However, the molecular mechanisms responsible for radiation-induced damage to the anal sphincter remain unclear. AIM: To determine the expression of transforming growth factor-beta 1 (TGF-beta 1) and its downstream effector connective tissue growth factor (CTGF) in the anal sphincter of a patient irradiated for prostate cancer. PATIENT: A 82 year-old patient developed a rectal adenocarcinoma and underwent an abdomino-perineal resection (APR), four years after receiving pelvic irradiation for prostate carcinoma. METHODS: Tissue sections of the anal sphincter were processed for histology. Immunostaining for TGF-beta 1 and CTGF were performed. RESULTS: CTGF and TGF-beta 1 immunoreactivity was detected in the irradiated anal sphincter, and was absent in controls. Immunoreactivity for both cytokines predominated in the internal sphincter. CTGF and TGF-beta 1 were preferentially detected in endothelial cells, myofibroblasts and fibroblasts; in addition, there was strong immunoreactivity for TGF-beta 1, but not for CTGF in smooth muscle cells of the anal canal. CONCLUSION: Four years after pelvic irradiation, radiation-induced damage appeared to affect predominantly the smooth muscle layer of the anal canal. The molecular mechanisms responsible for radiation-induced fibrosis to these tissues involve prolonged activation of TGF-beta 1 and its downstream effector CTGF.


Assuntos
Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Canal Anal/efeitos da radiação , Proteínas Imediatamente Precoces/análise , Peptídeos e Proteínas de Sinalização Intercelular/análise , Músculo Liso/efeitos da radiação , Neoplasias Induzidas por Radiação/cirurgia , Segunda Neoplasia Primária/cirurgia , Neoplasias da Próstata/radioterapia , Lesões por Radiação/patologia , Neoplasias Retais/cirurgia , Fator de Crescimento Transformador beta/análise , Idoso , Idoso de 80 Anos ou mais , Canal Anal/patologia , Fator de Crescimento do Tecido Conjuntivo , Progressão da Doença , Fibrose/patologia , Fibrose/cirurgia , Humanos , Técnicas Imunoenzimáticas , Masculino , Músculo Liso/patologia , Reto/patologia , Reto/efeitos da radiação , Reto/cirurgia , Reoperação , Fator de Crescimento Transformador beta1
8.
Stud Health Technol Inform ; 85: 529-31, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-15458146

RESUMO

In the treatment of malignant disease external beam radiation therapy (EBRT) is often combined with surgery. Intraoperative radiotherapy (IORT) improves the local control by dose escalation. For reasons of recording, improvement and security of the intervention, it would be necessary to merge the IORT-dose distribution with the postoperative CT-based EBRT-planing. The aim of this work was to develop a method to reconstruct the IORT field and register it with the postoperative planing CT. This enables the reconstruction of the IORT dose distribution and merge it with the CT-based EBRT planing data. We use a surface scanner to receive a large amount of surface points which enables us reconstruct the IORT-field and to register it with the CT-based EBRT planning data. Scanning and calculation time is not over 2 seconds, depending mainly on the CPU power. The error of a single point is below 1 mm. The density of the point cloud is approx. 4 per mm2. In this paper we give an overview of our experimental setup and the accuracy of the method.


Assuntos
Braquiterapia , Fracionamento da Dose de Radiação , Período Intraoperatório , Teleterapia por Radioisótopo , Planejamento da Radioterapia Assistida por Computador , Neoplasias Retais/radioterapia , Neoplasias Retais/cirurgia , Tomografia Computadorizada por Raios X , Interface Usuário-Computador , Terapia Combinada , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Cuidados Pós-Operatórios , Radioterapia Adjuvante
9.
Lab Invest ; 80(12): 1807-17, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11140694

RESUMO

Overexpression of receptors for regulatory peptides in various human diseases is reportedly of clinical interest. Among these peptides, bombesin and gastrin-releasing peptide (GRP) have been shown to play a physiological and pathophysiological role in pancreatic tissues. Our aim has been to localize bombesin receptors in the human diseased pancreas to identify potential clinical applications of bombesin analogs in this tissue. The presence of bombesin receptor subtypes has been evaluated in specimens of human pancreatic tissues with chronic pancreatitis (n = 23) and ductal pancreatic carcinoma (n = 29) with in vitro receptor autoradiography on tissue sections incubated with 125I-[Tyr4]-bombesin or the universal ligand 125I-[D-Tyr6, beta-Ala11, Phe13, Nle14]-bombesin(6-14) as radioligands and displaced by subtype-selective bombesin receptor agonists and antagonists. GRP receptors were identified in the pancreatic exocrine parenchyma in 17 of 20 cases with chronic pancreatitis. No measurable bombesin receptors were found in the tumor tissue of ductal pancreatic carcinomas, however, GRP receptors were detected in a subset of peritumoral small veins in 19 of 29 samples. Moreover, residual pancreatic islets in these tissues were shown to express the BB3 receptor subtype. These data demonstrate the presence of bombesin receptors in three distinct tissue compartments of the pancreas, namely GRP receptors in the exocrine parenchyma in chronic pancreatitis and in peritumoral vessels around ductal pancreatic carcinomas, and BB3 receptors in residual pancreatic islets. Such a selective expression of bombesin receptor subtypes in pancreatic tissues may not only be of pathophysiological significance but may represent the basis for potential diagnostic and therapeutic clinical applications of bombesin analogs, including GRP receptor scintigraphy to differentiate chronic pancreatitis from ductal pancreatic carcinoma.


Assuntos
Adenocarcinoma/patologia , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Pancreatite/patologia , Receptores da Bombesina/análise , Receptores da Bombesina/classificação , Autorradiografia , Doença Crônica , Fibrose , Humanos , Inflamação , Radioisótopos do Iodo , Ductos Pancreáticos , Neoplasias Pancreáticas/classificação
11.
Cancer ; 43(3): 1095-100, 1979 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-311679

RESUMO

Twenty-three patients with advanced recurrent head and neck carcinoma were randomized to receive either high dose methotrexate with calcium leucovorin rescue (HDMTX) or HDMTX in combination with bacilli Calmette Guerin (HDMTX/BCG). An additional eight patients were treated with escalating doses of HDMTX ranging from 1 to 7 g of methotrexate. Of 12 patients receiving HDMTX, one complete response and two partial responses were noted. Of 11 patients in the HDMTX/BCG group, one complete response and two partial responses were observed. Only one partial response was noted in eight patients receiving escalating doses of the drug. Responses were brief and no significant difference in response duration was seen in any particular group. Toxicities in all groups were tolerable. BCG did not improve response rate, median duration of response, or median survival in these patients. Reported experiences with high dose methotrexate have been reviewed and again, responses to "high dose methotrexate" were found to be of brief duration. Despite acceptable toxicity, the brief duration of response and cost of such therapy raises serious question on the usefulness of chemoimmunotherapy utilizing high dose methotrexate with leucovorin rescue and BCG in the management of advanced recurrent carcinomas of the head and neck region.


Assuntos
Vacina BCG/uso terapêutico , Carcinoma de Células Escamosas/terapia , Carcinoma de Células de Transição/terapia , Neoplasias de Cabeça e Pescoço/terapia , Metotrexato/administração & dosagem , Adulto , Idoso , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células de Transição/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Leucovorina/administração & dosagem , Metotrexato/efeitos adversos , Pessoa de Meia-Idade , Estomatite/induzido quimicamente
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