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61.
G Costin  M D Kogut  C Hyman  J A Ortega 《Diabetes》1977,26(3):230-240
To investigate the development of diabetes mellitus in patients with thalassemia major, plasma glucose and immunoreactive insulin (IRI) levels following oral glucose and intravenous tolbutamide and glucose disappearance rates following intravenous insulin were measured in 10 patients before and during five years on a high transfusion program (HTP). Plasma immunoreactive glucagon (IRG) levels following oral glucose, intravenous insulin, and arginine were measured during the sixth year. Serial percutaneous liver biopsies were performed on seven patients. The oral glucose tolerance tests (OGAT) and mean peak IRI levels were normal in nine of 10 patients before HTP. After HTP was begun a progressive deterioration of OGTT occurred despite normal IRI levels. Following tolbutamide, the mean per cent fall in plasma glucose in the patients before HTP was significantly less than in controls (p less than 0.01) and similar to that of controls during five years of HTP in spite of higher than normal peak IRI levels. Of seven survivors after six years of HTP, three had normal OGTT and four had chemical diabetes; mean peak IRI levels were normal, but fasting IRG levels were significantly higher than in controls (p less than 0.05). In all seven patients, plasma IRG failed to increase following insulin-induced hypoglycemia and was significantly higher than in controls after arginine (p less than 0.01); after oral glucose, plasma IRG fell significantly below that of fasting only in the patients with chemical diabetes (p less than 0.03). Following intravenous insulin, the mean per cent fall in glucose before and during HTP was significantly less than in controls (p less than 0.01). Hemosiderosis and cirrhosis were present in all biopsied patients. Four patients died; two had chemical and two had nonketotic insulin-dependent diabetes. These data suggest that diabetes mellitus occurs frequently in patients with thalassemia on HTP and that insulin resistance and hyperglucagonemia, possibly due to cirrhosis, are important etiologic factors.  相似文献   
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63.
PURPOSE: This analysis was performed to determine the long-term results of a Phase I trial that included 3-times-a-day radiotherapy (TIDRT) and concurrent daily cisplatin (CDDP) for Stage III non-small-cell lung cancer. METHODS AND MATERIALS: Twenty patients with Stage III non-small-cell lung cancer were treated with TIDRT delivered over 12 weekdays that included 57.6 Gy administered in 1.5 Gy fractions at 8 a.m. and 4 p.m., and 1.8 Gy fractions at noon. AP-PA fields were used at 8 a.m. and 4 p.m. Opposed oblique off cord fields were used at noon. The first 5 patients were given no CDDP, the second 5 patients received 5 mg/m2 of CDDP, and the remaining 10 patients received 7.5 mg/m2 of CDDP. All survivors were followed for greater than 5 years. RESULTS: The maximum tolerated dose of daily CDDP during this program of radiation therapy was 7.5 mg/m2. None of the patients died as a result of toxicity. The median survival was 19.2 months, and the 5-year survival rate was 25%. Tumor response and patterns of failure were also evaluated. CONCLUSIONS: This study was performed to determine the maximum tolerated dose of CDDP when administered daily during an aggressive program of TIDRT. The survival results were promising, suggesting that the combination of TIDRT and systemic therapy deserves further study.  相似文献   
64.
Yeast species such as Saccharomyces cerevisiae are known to be potent activators of the immune system. S. cerevisiae activates the innate immune system by engaging pattern recognition receptors such as toll like receptor 2 (TLR2) and dectin-1. In the current project, we express the immunogenic envelope protein E2 of bovine viral diarrhoea virus (BVDV) on the surface of S. cerevisiae. After successful expression, components of the innate and adaptive immune response induced by the recombinant S. cerevisiaein vitro were analysed to determine if expression in yeast enhances the immunogenicity of the viral protein. Recombinant S. cerevisiae stimulated production of the chemokine CXCL-8 in primary bovine macrophages, but did no stimulate production of reactive oxygen species (ROS) in the same cells. Additionally, bovine macrophages primed with S. cerevisiae expressing viral envelope proteins had a greater capacity for stimulating proliferation of CD4+ T-cells from BVDV-free animals compared to macrophages primed with envelope protein alone or S. cerevisiae without envelope protein expression. Heat inactivation of recombinant S. cerevisiae increased ROS production and capacity to stimulate CD4+ T-cells in macrophages but did not alter CXCL-8 release compared to the live counter-part. Additionally, heat-inactivation of recombinant S. cerevisiae induced less INFγ and IL-4 but equal amounts of IL-10 compared to live yeast T-cell cultures. Our studies demonstrate a use for S. cerevisiae as a vehicle for transporting BVDV vaccine antigen to antigen-presenting cell in order to elicit cell-mediated immunity even in na?ve animals.  相似文献   
65.
Toll-like receptors (TLRs) play a major role in the innate immune system for initial recognition of microbial pathogens and pathogen associated components. Nitric oxide (NO) is generated in immune cells in response to microbial stimulation and is involved in pathogenesis and control of infection. We used RT-PCR analysis to examine the TLR expression profile on chicken monocytes and demonstrated these cells express chicken TLR2, 3, 4, 6, and 7. TLR5 was not detected by the TR-PCR. We also investigated the differential induction of NO synthesis in chicken monocytes by TLR agonists, including flagellin (FGN, from Salmonella typhimurium), synthetic lipoprotein Pam3CSK4 (PAM), lipopolysaccharide (LPS, from Salmonella enteritidis), lipoteichoic acid (LTA, from Staphylococcus aureus), the synthetic double stranded RNA analog (poly I:C), the guanosine analog, loxoribine (LOX), and synthetic CpG oligodeoxydinucleotide (CpG-ODN). Our results indicate that there was a vast difference among these agonists for their ability to induce NO production. CpG-ODN and LPS were the most potent stimuli and induced significant quantities of NO in cultured monocytes, whereas LTA stimulated significant NO production only at high concentrations. Other agonists such as FGN and poly I:C stimulated very little NO, while PAM, LOX, and nCpG-ODN (control ODN) did not induce NO production. RT-PCR analysis demonstrated that LPS, LTA, and CpG-ODN induced inducible nitric oxide synthase (iNOS) expression in monocytes; whereas the other agonists did not. The presence of TLRs on chicken monocytes and the differential induction of NO production in chicken monocytes by various TLR agonists suggest the differentiation of signaling pathways downstream of individual TLRs.  相似文献   
66.
Radiology conferences enable participants the opportunity to ask experts questions through question and answer (Q and A) sessions or individually. Given the time limitations and intimidating circumstances, we incorporated conference text messaging (confexting) as a method of increasing interactivity between the audience and speakers. During a 5-day radiology conference, text messaging was utilized for anonymous interactivity between the audience and speakers during Q and A sessions. There were 324 text messages; 76 of these were either follow-up statements or questions related to earlier text messages. Forty-two questions were submitted via paper notes. There was a general trend of an increasing number of text messages and a decreasing number of paper notes. The anonymous text messaging system was found to be an effective method for interactivity between the audience and the speakers. The questions and answers could be presented in a PowerPoint format at the formal Q and A sessions. Questions texted to the authors during their talks could be immediately answered or addressed in subsequent talks. Although difficult for some individuals to embrace technology, confexting allows for interactivity and prompts discussion. Confexting is an effective method for interactivity between the audience and speakers not previously utilized in a conference setting. The anonymity and asynchronous communication enable conference participants to submit more questions than in the traditional setting. The speakers may be able to explain more thoroughly difficult concepts more thoroughly with additional slides at Q and A sessions or may immediately answer texted questions during their talks.  相似文献   
67.
Enterococci, gram-positive bacterium, are found on virtually all consumer-ready retail meats. Recently, we characterized the innate immune response phenotype of parental lines of broilers (A and B) and F1 reciprocal crosses (C and D). In vitro heterophil functional analyses and in vivo challenge trials showed line A was more immunologically responsive and more resistant to Salmonella (Gram-negative bacteria) and Eimeria tenella (parasitic protozoan) infections than line B. Further, cross D was more responsive with increased resistance compared to cross C. We hypothesized that line A and D chickens were also more resistant to gram-positive bacteria. Day-old chickens were challenged with vancomycin-resistant Enterococcus gallinarum (VREG), euthanized, and hearts, livers, and spleens cultured for VREG. One-day post challenge, there were significantly fewer VREG-positive hearts, livers, and spleens in line A than line B. Likewise, cross D chickens had significantly fewer VREG-positive hearts, livers, and spleens than cross C chickens. To determine if VREG was cleared, chickens were necropsied seven days post-challenge. Again, significantly fewer organ cultures from line A and D were VREG-positive compared to line B and C. Further, this study showed the hematologic profile reflected changes associated with protection against VREG; there were significantly more circulating heterophils and monocytes in VREG-resistant lines A and D with no changes in VREG-susceptible lines B and C. Collectively, line A and D chickens are immunologically more responsive and more resistant to pathogens, including VREG, compared to line B and C chickens.  相似文献   
68.
Autologous hematopoietic stem cell transplantation (autoSCT) is an effective treatment for patients with various hematologic malignancies. Despite the significant improvement in the overall outcome, disease progression after transplantation remains the major cause of treatment failure. With longer follow-up, therapy-related myelodysplasia/acute myelogenous leukemia is becoming an important cause of treatment failure. The prognosis for these 2 groups of patients is very poor. Allogeneic hematopoietic stem cell transplantation (alloSCT) is a potential curative treatment for these patients. However, the outcome with conventional myeloablative alloSCT after failed autoSCT is typically poor because of high transplant-related mortality. In an attempt to reduce the treatment-related toxicity, we studied a reduced-intensity conditioning regimen followed by alloSCT for patients with progressive disease or therapy-related myelodysplasia/acute myelogenous leukemia after autoSCT. This report describes the outcomes of 28 patients with hematologic malignancies who received a reduced-intensity alloSCT after having treatment failure with a conventional autoSCT. Fourteen patients received a hematopoietic stem cell transplant from a related donor and 14 from an unrelated donor. The conditioning regimen consisted of low-dose (2 Gy) total body irradiation with or without fludarabine in 4 patients and the combination of melphalan (140 mg/m(2)) and fludarabine in 24. Cyclosporine and mycophenolate mofetil were used for posttransplantation immunosuppressive therapy, as well as graft-versus-host disease (GVHD) prophylaxis, in all patients. All patients engrafted and had >90% donor chimerism on day 100 after SCT. Currently, 13 patients (46%) are alive and disease free, 7 patients (25%) developed disease progression after alloSCT, and 8 (32%) died of nonrelapse causes. Day 100 mortality and nonrelapse mortality were 25% and 21%, respectively. With a median follow-up of 24 months for surviving patients, the 2-year probabilities of overall survival, event-free survival, and relapse rates were 56.5%, 41%, and 41.9%, respectively. Six patients (21%) developed grade III to IV acute GVHD. Among 21 evaluable patients, 15 (67%) developed chronic GVHD. We conclude that (1) reduced-intensity alloSCT is feasible and has an acceptable toxicity profile in patients who have previously received autoSCT and that (2) although follow-up was short, a durable remission may be achieved in some patients who would otherwise be expected to have a poor outcome.  相似文献   
69.
Objective Although previous studies have examined the impact of maternal depression on child overweight and obesity, little is known about the relationship in Latino families, who suffer from high risks of depression and obesity. We prospectively investigated the association between depressive symptoms in women with young children and child overweight and obesity (overweight/obesity) at age 7 years among Latino families. Methods Participants included 332 singletons with anthropometric measures obtained at 7 years from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study, a birth cohort study. Maternal depression was assessed using the Center for Epidemiologic Studies-Depression (CES-D) scale when the children were 1, 3.5, and 7 years. Overweight and obesity was measured by body mass index (kg/m2) at age 7 years. Results 63 % of women had CES-D scores consistent with depression in at least one of the 3 given assessments. Compared to children whose mothers were never depressed, children whose mothers were depressed at all three assessments had 2.4 times the adjusted odds of overweight/obesity at age 7 years (95 % CI 1.1–5.6). However, a single positive maternal depression screen was not associated with child overweight/obesity and there was no difference in the odds of overweight/obesity by the age of the child when maternal depression occurred. Conclusion Chronic maternal depression during a child’s early life was associated with child overweight/obesity at 7 years. Addressing maternal depression is a critical component of comprehensive obesity prevention and treatment strategies for Latino children.  相似文献   
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