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101.
Dominicans are the largest migrant community in Puerto Rico, yet understudied. We compared risk factors and health conditions of Dominicans versus Puerto Ricans (PRs). Cross-sectional survey of Dominicans (n?=?55) and PRs (n?=?310) aged 30–75 years, assessed with validated questionnaires and standardized anthropometric measurements. Significantly, more Dominicans than PRs had attained <8th grade education (37.7 vs. 8.0%), reported household income ≤$10,000 (76.1 vs. 56.9%), lacked health insurance (19.6 vs. 5.5%), and reported food insecurity (24.5 vs. 12.1%). They spent fewer hours/day watching television (2.9 vs. 3.8), and were less likely to smoke (7.6 vs. 19.6%). Medically-diagnosed depression was lower among Dominicans than PRs (9.6 vs. 23.0%); questionnaire-based high depressive symptomatology was similar (47.9 vs. 52.8%). Dominicans living in Puerto Rico had more socioeconomic risk factors but healthier lifestyle behaviors and lower prevalence of medically-diagnosed depression than PRs. Tailored approaches are needed to ameliorate disparities in each ethnic group.  相似文献   
102.
Schmorl's nodes were first described by the pathologist Christian Schmorl in 1927 as a herniation of the nucleus pulposus through the cartilaginous and bony endplate into the vertebral body. Although such lesions present most commonly as incidental findings in asymptomatic patients (or in patients with back or radicular pain due to other etiology), there have been several reports emphasizing the deleterious effects of the inflammatory response and endplate changes elicited by the herniation of for such reasons, Schmorl's nodes have been occasionally implicated in the etiology of chronic axial pain as well as in pathological osteoporotic fractures. In this article, a thorough literature review about the most relevant historical studies on Schmorl's nodes previously published is performed. Furthermore, the authors provide an overview about the recent advances in basic science research on the pathophysiology of such lesions, as well as on current diagnostic and therapeutic paradigms.  相似文献   
103.

Context

Because pelvic lymph node (LN)-positive prostate cancer (PCa) is generally considered a regionally metastatic disease, surgery needs to be better defined.

Objective

To review the impact of radical prostatectomy (RP) and pelvic lymph node dissection (PLND), possibly in conjunction with a multimodal approach using local radiotherapy and/or androgen-deprivation therapy (ADT), in LN-positive PCa.

Evidence acquisition

A systematic Medline search for studies reporting on treatment regimens and outcomes in patients with LN-positive PCa undergoing RP between 1993 and 2012 was performed.

Evidence synthesis

RP can improve progression-free and overall survival in LN-positive PCa, although there is a lack of high-level evidence. Therefore, the former practice of aborting surgery in the presence of positive nodes might no longer be supported by current evidence, especially in those patients with a limited LN tumor burden. Current data demonstrate that the lymphatic spread takes an ascending pathway from the pelvis to the retroperitoneum, in which the internal and the common iliac nodes represent critical landmarks in the metastatic distribution. Sophisticated imaging technologies are still under investigation to improve the prediction of LN-positive PCa. Nonetheless, extended PLND including the common iliac arteries should be offered to intermediate- and high-risk patients to improve nodal staging with a possible benefit in prostate-specific antigen progression-free survival by removing significant metastatic load. Adjuvant ADT has the potential to improve overall survival after RP; the therapeutic role of a trimodal approach with adjuvant local radiotherapy awaits further elucidation. Age is a critical parameter for survival because cancer-specific mortality exceeds overall mortality in younger patients (<60 yr) with high-risk PCa and should be an impetus to treat as thoroughly as possible.

Conclusions

Increasing evidence suggests that RP and extended PLND improve survival in LN-positive PCa. Our understanding of surgery of the primary tumor in LN-positive PCa needs a conceptual change from a palliative option to the first step in a multimodal approach with a significant improvement of long-term survival and cure in selected patients.  相似文献   
104.
The hyperimmunoglobulinemia D and periodic fever (hyper-IgD) syndrome is typified by recurrent febrile attacks with abdominal distress, joint involvement (arthralgias/arthritis), headache, skin lesions, and an elevated serum IgD level (> 100 U/mL). This familial disorder has been diagnosed in 59 patients, mainly from Europe. The pathogenesis of this febrile disorder is unknown, but attacks are joined by an acute-phase response. Because this response is considered to be mediated by cytokines, we measured the acute-phase proteins C-reactive protein (CRP) and soluble type-II phospholipase A2 (PLA2) together with circulating concentrations and ex vivo production of the proinflammatory cytokines interleukin-1 alpha (IL-1 alpha), IL-1 beta, IL-6, and tumor necrosis factor alpha (TNF alpha) and the inhibitory compounds IL-1 receptor antagonist (IL-1ra), IL-10, and the soluble TNF receptors p55 (sTNFr p55) and p75 (sTNFr p75) in 22 patients with the hyper-IgD syndrome during attacks and remission. Serum CRP and PLA2 concentrations were elevated during attacks (mean, 213 mg/L and 1,452 ng/mL, respectively) and decreased between attacks. Plasma concentrations of IL-1 alpha, IL-1 beta, or IL-10 were not increased during attacks. TNF alpha concentrations were slightly, but significantly, higher with attacks (104 v 117 pg/mL). Circulating IL-6 values increased with attacks (19.7 v 147.9 pg/mL) and correlated with CRP and PLA2 values during the febrile attacks. The values of the antiinflammatory compounds IL-1ra, sTNFr p55, and sTNFr p75 were significantly higher with attacks than between attacks, and there was a significant positive correlation between each. The ex-vivo production of TNF alpha, IL-1 beta, and IL-1ra was significantly higher with attacks, suggesting that the monocytes/macrophages were already primed in vivo to produce increased amounts of these cytokines. These findings point to an activation of the cytokine network, and this suggests that these inflammatory mediators may contribute to the symptoms of the hyper-IgD syndrome.  相似文献   
105.
To investigate the mechanisms underlying the deficiency of T lymphocytes from patients with Hodgkin's disease, we investigated the expression of the T-cell receptor (TCR) zeta chain in patients with Hodgkin's disease. By flow cytometry using an anti-zeta chain monoclonal antibody, peripheral blood T lymphocytes from patients with untreated Hodgkin's disease were shown to express decreased levels of the TCR zeta chain. After stimulation by combined CD3 and CD28 cross- linking, T cells from Hodgkin's disease patients upregulated zeta chain protein expression to normal values within 48 hours and achieved a cytolytic potential and levels of interleukin (IL)-2 secretion that were not different from T cells obtained from healthy controls. These results show that downregulation of the TCR zeta chain in Hodgkin's T lymphocytes is a reversible event. Costimulation of CD3 and CD28 is a novel approach for overcoming the T-cell deficiency in Hodgkin's disease and might be exploited clinically. As upregulation of the zeta chain can also be achieved using bispecific monoclonal antibodies (BI- MoAbs) with specificity for tumor antigens and CD3 and CD28, respectively, an immunotherapy with CD3/CD30 and CD28/CD30 Bi-MoAbs may overcome and should therefore, not be jeopardized by the inherent T- cell deficiency in patients with Hodgkin's disease.  相似文献   
106.
107.
108.
High-dose intravenous gammaglobulin (polyvalent immunoglobulin G) has been shown to be of benefit in some patients with immune thrombocytopenic purpura (ITP), possibly by producing reticuloendothelial system blockade. We studied this approach in patients refractory to random donor platelet transfusion using an IV IgG preparation manufactured by the Swiss Red Cross. Eleven adult patients with acute leukemia received either 0.4 g IgG/kg/d intravenously X five days (four patients) or 0.6 g/kg/d X five days (seven patients). All patients had high levels of lymphocytotoxic antibody and poor responses to random donor platelets. Except for mild headaches in two patients, there were no side effects related to the IgG infusions. All patients had significant elevations of serum IgG on the day after completion of treatment. Either random donor or partially HLA-matched platelet transfusions were administered the day after and, in some cases, during the IgG therapy. No patient had an improvement in one hour posttransfusion platelet count increments. Two additional patients received pooled platelet concentrates incubated for 30 minutes at 37 degrees C with IgG at a final concentration of 3 g% prior to transfusions. These results indicate that high-dose IgG, an extremely expensive treatment, cannot be recommended for alloimmunized adults with leukemia.  相似文献   
109.
Deegan  MJ; Abraham  JP; Sawdyk  M; Van Slyck  EJ 《Blood》1984,64(6):1207-1211
Chronic lymphocytic leukemia (CLL) is generally considered a nonsecretory B cell immunoproliferative disorder. Conventional electrophoretic and immunoelectrophoretic methods have revealed serum monoclonal proteins in less than 10% of these patients. However, there is increasing experimental evidence from in vitro studies demonstrating that CLL cells may secrete immunoglobulins, particularly free light chains. We examined the serum and urine of 36 consecutive CLL patients for monoclonal proteins using sensitive immunochemical methods (high resolution agarose gel electrophoresis combined with immunofixation). The results obtained were correlated with the Rai stage, quantitative immunoglobulin levels, and lymphocyte membrane immunoglobulin phenotype of the leukemic cells. Twenty-three monoclonal proteins were identified in the serum or urine of 22 patients, an incidence of 61%. Six patients had serum monoclonal proteins, seven had only urinary monoclonal proteins, and nine had monoclonal proteins in serum and urine. In every instance the monoclonal protein was the same light chain type as expressed on the leukemic cells. Our findings suggest that the monoclonal proteins observed in the serum or urine of CLL patients are secretory products of the tumor cells and that their discovery is a function of the sensitivity of the method used for their detection.  相似文献   
110.
Fast  LD; Valeri  CR; Crowley  JP 《Blood》1995,86(8):3090-3096
Graft-versus-host disease (GVHD) is currently encountered after bone marrow transplantation and transfusion. GVHD associated with transfusion (TA-GVHD) in apparently immunocompetent recipients has been recently reported with increasing frequency. A consistent finding in many of these cases is that the recipient received blood from a donor homozygous for one of the recipient's HLA haplotypes. However, the observed frequency of TA-GVHD is much lower than the estimated probability of this donor/recipient combination. The potential role of recipient immune responses in controlling TA-GVHD was investigated using an analogous murine model in which GVHD is induced by the injection of parental lymphoid cells into unirradiated F1 hybrid recipients. The effect of various immune manipulations of the recipient of GVHD induction was assessed by determining the number of donor lymphoid cells required to induce GVHD responses. Whereas depletion of recipient CD4+ cells increased the number of donor cells needed to induce GVHD, depletion of recipient CD8+ and natural killer cells resulted in fewer donor cells being needed to induce a GVHD response. These studies suggest a central role for functioning recipient CD8 and natural killer cells in the down-regulation of TA-GVHD development in recipients.  相似文献   
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