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171.
In studies of sexual mucosal transmission and early stages of simian immunodeficiency virus (SIV) and HIV infections, productive infection predominates in CD4+ T cell populations, in both ostensibly resting and activated cells. The surprising ability of SIV and HIV to replicate in resting cells in vivo, in contrast to propagation of infection in vitro, suggested a model in which during the early stages of infection these viruses exploit the greater availability of resting cells to maintain unbroken chains of transmission from an infected resting cell to another resting cell nearby. Because immune activation in response to infection provides more activated CD4+ T cells, these viruses take advantage of the greater efficiency of virus production and spread in activated cells for propagation and dissemination of infection. In this article, we report the results of experimental tests of this model, including visualization at the light microscopic level and direct analysis of virus production by cells in tissues. Analysis of tissues of rhesus macaques inoculated intravaginally or i.v. with SIV supports the proposed roles of target cell availability, susceptibility, and virus production by infected resting and activated CD4+ T cells in mucosal transmission and early infection, and points to a potential role for topical anti-inflammatory agents in moderating the initial propagation of infection.  相似文献   
172.
Haase C  Skak K  Michelsen BK  Markholst H 《Diabetes》2004,53(10):2588-2595
The initial events leading to activation of the immune system in type 1 diabetes are still largely unknown. In vivo, dendritic cells (DCs) are thought to be the only antigen-presenting cells (APCs) capable of activating na?ve T-cells and are therefore important for the initiation of the autoimmune response. To test the effect of activating islet-associated APCs in situ, we generated transgenic mice expressing CD154 (CD40 ligand) under control of the rat insulin promoter (RIP). RIP-CD154 mice developed both insulitis and diabetes, although with different incidence in independent lines. We show that activated DCs could be detected both in the pancreas and in the draining pancreatic lymph nodes. Furthermore, diabetes development was dependent on the presence of T- and B-cells since recombination-activating gene (RAG)-deficient RIP-CD154 mice did not develop diabetes. Finally, we show that the activation of immune cells was confined to the pancreas because transplantation of nontransgenic islets to diabetic recipients restored normoglycemia. Together, these data suggest that expression of CD154 on the beta-cells can lead to activation of islet-associated APCs that will travel to the lymph nodes and activate the immune system, leading to insulitis and diabetes.  相似文献   
173.

Background/purpose

Previous reports indicate that complete resection of high-risk neuroblastoma improves outcome but may entail high surgical complication rates. The authors evaluated the effect of complete primary site resection on event-free survival (EFS), overall survival (OS), and complication rates in patients entered on a high-risk neuroblastoma treatment protocol.

Methods

A total of 539 eligible patients with high-risk neuroblastoma were entered on protocol CCG-3891. Patients were assigned randomly to continuation chemotherapy or autologous bone marrow transplantation. Surgical resection was performed at diagnosis or after induction chemotherapy. Surgeons assessed resection as complete (CR), minimal residual (<5%, MR), or partial (PR). Incomplete resections received secondary resection or 10 Gy of external beam radiation. Patients were evaluated for EFS, OS, and complications of surgery based on completeness of overall best resection.

Results

The proportion of patients resectable at diagnosis was 27% for CR and 14% for MR. This improved after chemotherapy to 45% and 25%. Complication rates based on completeness of resection were 29%, 38%, and 36% for CR, MR, and PR, respectively. Estimated 5-year EFS rate was 30% ± 3% for patients who achieved CR (n = 210) compared with 25% ± 3% (P = .1010) for those with less than CR (n = 258).

Conclusions

Resectability improved after neoadjuvant chemotherapy. Complete resection did not increase complications. There was a small survival benefit for complete resection. This study suggests that complete resection may still be important in the current era of intense chemotherapy and transplant.  相似文献   
174.
Background Laparoscopic colorectal resection improves patient outcome by reducing pain, postoperative pulmonary dysfunction, gastrointestinal paralysis, and fatigue. A multimodal rehabilitation program (fast-track) with epidural analgesia, early oral feeding, and enforced mobilization may further improve the excellent results of laparoscopic colorectal resection, enabling early ambulation of these patients.Methods Fifty two consecutive patients underwent laparoscopic sigmoidectomy with standardized regular perioperative treatment (standard) or multimodal rehabilitation program (fast-track). Outcome measures included pulmonary function, duration of postoperative ileus, pain perception, fatigue, morbidity, and mortality.Results Twenty nine standard-care patients (19 men and 10 women) and 23 fast-track patients (15 men and eight women) were evaluated. Demographic and operative data were similar for the two groups. On the 1st postoperative day, pulmonary function was improved (p = 0.01) in fast-track patients. Oral feeding was achieved earlier (p < 0.01) and defecation occurred earlier (p < 0.01) in the fast-track group. Visual analogue scale scores for pain were similar for the two groups (p > 0.05), but fatigue was increased in the standard-care group on the 1st (p = 0.06) and 2nd (p < 0.05) postoperative days. Morbidity was not different for the two groups. Fast-track patients were discharged on day 4 (range, 3–6) and standard-care patients on day 7 (range, 4–14) (p < 0.001).Conclusion Multimodal rehabiliation can improve further on the excellent results of laparoscopic sigmoidectomy and decrease the postoperative hospital stay.Note: Author W. Schwenk is a member of the German Advisory Board for Parecoxib/Valdecoxib of the Pfizer Company.  相似文献   
175.
OBJECTIVE: To determine the optimum conditions for the proliferation of urothelial cells, leading to the confluent coverage of large surfaces of biocompatible membranes, and for their terminal differentiation. MATERIALS AND METHODS: Porcine and human urothelial cells were cultured on different matrices under different growth conditions. Proliferative activity and the viability of cells were evaluated using fluorescent markers for nuclei and cytoplasm. Growth and differentiation were assessed by histological, histochemical and immunohistochemical methods. RESULTS: Under fibroblastic induction and supplementation of 5% fetal calf serum (FCS), urothelial cells showed more proliferation than in other conditions tested. Terminal differentiation of superficial cells was achieved by lowering the concentration of FCS to 1% at the air-liquid interface. CONCLUSIONS: The mitogenic effects of the extracellular matrix content of biological membranes and fibroblastic inductive factors are synergistic with each other, and can compensate for a low FCS concentration and the absence of other additives. Lowering the FCS concentration to 1% inhibits the proliferation of urothelial cells and permits their terminal differentiation.  相似文献   
176.
OBJECTIVES: In multiple sclerosis (MS), several neuroimmunomodulatory effectors are known, including melatonin. They are able to influence disease-related neurophysiogical changes (disability or impaired vision) as well as neuropsychological performance (e.g. cognition and depression). In this study we assessed the relationship between immunomodulation on psycho-neuroimmunological functions in benign multiple sclerosis. METHODS: We evaluated 26 young female patients with benign MS treated with/without immunomodulating therapies with regard to their physical disabilities (Expanded Disability Status Scale, EDSS), their visually evoked potentials (VEP), their plasma melatonin concentrations as well as their performance regarding emotional and cognitive tests and compared them with healthy matched controls. RESULTS: Patients with MS showed deficits in cognitive and emotional functions compared to healthy controls, which were in accordance with their increase in EDSS over time. However, in contrast to untreated patients, patients receiving immunotherapy showed significantly increased dysfunction with respect to actual mood (p = 0.02) and a tendency to increased depression scores (p = 0.072). However, neither treatment subgroup had cognitive deficits. In untreated patients, melatonin levels correlated with reduced scores in the cognitive tests (p = 0.045) but not with depression or VEP latencies. Patients with long-standing MS (>10 years) showed a significant correlation (p = 0.01) to their increased depression scores and their melatonin levels, but no correlation with VEP or cognitive dysfunction, compared to patients with shorter disease duration (< or =10 years). CONCLUSION: These results indicate that in MS all aspects of the psycho-neuroimmunological network can be affected. Despite the potential influence of immunomodulation on depression, no connection with melatonin representing the retinohypothalamic tract/pineal gland circuits could be detected. However, visual perception as well as visuoconstructive abilities were affected in MS patients. Neuropsychological tests in MS should concentrate on cognitive variables, which reflect the clinical status more accurately and may be used to monitor disease-modifying therapies.  相似文献   
177.
B-cell chronic lymphocytic leukemia (B-CLL) is phenotypically characterized by cell surface co-expression of CD19, CD20, CD5, and CD23. However, the concomitant presence of other antigens distinctive of a particular leukocyte subset, e.g. T cells, is an unusual finding in B-CLL. In the present report, a case of B-CLL with aberrant expression of the T-cell-associated antigen CD8 is described. Flow cytometric analysis of the patient's cells demonstrated lack of CD38 expression, and cytogenetic analysis by FISH did not show any abnormalities of chromosomes 17p, 11q, and 12. Furthermore, the B-CLL cells expressed only low levels of the tyrosine kinase ZAP-70, which was in agreement with the mutated status of the immunoglobulin heavy-chain variable-region gene (IgVH). In summary, the determined profile of prognostic markers together with the highly stable and indolent disease in the described patient suggest a good prognosis of B-CLL with aberrant CD8 expression.  相似文献   
178.
Knowledge of peripartum indicators of those mother-infant pairs that are at increased risk of early failure of lactation may improve specific support of breastfeeding. Mode of delivery, labor complications, hyperbilirubinemia, milk intake and weight development were evaluated in healthy term infants in a hospital (n = 338). Delayed onset of lactation was observed in primiparae and in study participants with peripartum complications. The quantitative intake of human milk, assessed by test weighing 0-24 h and 24-48 h after the onset of lactation, was not significantly different between these groups. In addition, volume intake, weight gain and lactation success were tracked in 77 infants. Partial feeding of infant formula or an intake of <150 g of human milk per day 24-48 h after the onset of lactation was linked to weaning within 4 weeks. Ninety-one percent of the infants were exclusively breastfed at discharge; this value had declined to 49, 35 and 20% at 4, 12 and 20 weeks, respectively. Peripartum factors may contribute to early lactation failure; the long-term success of breastfeeding was predominantly determined outside the hospital.  相似文献   
179.
BACKGROUND: As a result of improved therapeutic and diagnostic modalities the survival rate of children with neoplastic disease has increased dramatically. The consequences of these scientific advances have led to increased malignancy-related critical complications requiring the expertise of intensive care practitioners. PATIENTS: From all children admitted to the pediatric intensive care unit (PICU) of the Martin-Luther University Halle those with hematologic-oncologic condition were evaluated. RESULTS: From 4068 PICU admissions 196 (4.8%) oncologic patients were identified. Most of them were admitted for postoperative care, monitoring or intervention. 24 patients were admitted because of severe disease or treatment related complications. 14 out of 24 (58%) patients died on PICU. Mortality was significant higher in a subgroup requiring mechanical ventilation or suffering from sepsis. All patients but two with multi-organ system failure (> or = 2 organs) died. CONCLUSIONS: Children with neoplastic disease can benefit from pediatric intensive care unit (PICU) support. Successful treatment of life-threatening complications requires a close cooperation of pediatric oncology and PICU. Further studies are necessary to improve therapeutic strategies in oncology patients requiring PICU admission.  相似文献   
180.
Allogeneic stem cell transplantation (allo-SCT) plays an important role in the treatment of infants and children with acute myelogenous leukemia (AML). Leukemic relapse after allo-SCT is responsible for a high rate of treatment failure. Extra-medullary relapse (EMR), without involvement of bone marrow, is rare compared to medullary relapse. CD56, the neural cell adhesion molecule, may contribute to the higher frequency of CNS relapse in CD56-positive AML. We observed an isolated EMR on the oculomotor nerve of a 17-month-old girl 12 weeks after cord blood transplantation (CBT), who was transplanted because of CD56-positive AML. Diagnosis of relapse was suspected clinically and confirmed by magnetic resonance imaging (MRI), and fluorescence-activated cell sorter (FACS) and chimerism analysis of cerebrospinal fluid (CSF). Therapy consisted of intra-thecal chemotherapy, CNS irradiation, and systemic immunomodulation by cyclosporin A (CsA) and basiliximab withdrawal. Twenty-one months after relapse, the patient shows full remission of symptoms and previously described oculomotor nerve infiltration.  相似文献   
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