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1.
BACKGROUND: Cutaneous cancers exhibit a much higher incidence in patients with chronic lymphocytic leukemia than in nonleukemic patients. Squamous and basal cell carcinomas also exhibit greater subclinical tumor extension in patients with chronic lymphocytic leukemia. OBJECTIVE: The purpose of this study was to estimate and compare the recurrence rates of squamous cell carcinoma after Mohs' surgery in patients with chronic lymphocytic leukemia compared with those in controls and to evaluate differences among squamous cell carcinoma size and histologic grade. METHODS: We retrospectively assessed the clinical histories, postoperative notes, and surgical photographs of patients with chronic lymphocytic leukemia and controls matched (2:1) for age, sex, and surgical year. Both patients and controls underwent Mohs' surgery for squamous cell carcinoma of the head and neck at the Mayo Clinic between March 1988 and April 1999. RESULTS: Twenty-eight patients who underwent Mohs' surgery for 57 squamous cell carcinomas had 7 recurrences. The cumulative incidence of recurrence on a per-tumor basis was 4.3% at 1 year, 14.8% at 3 years, and 19.0% at 5 years. Squamous cell carcinoma was seven times more likely to recur in patients with chronic lymphocytic leukemia than in controls (p = .003). The distribution of tumor histologic grade was not significantly different between patients and controls (p = .39). Maximum preoperative tumor diameters were clinically similar between patients and controls (median 15 mm vs 14 mm; p = .04). CONCLUSION: The recurrence rates of squamous cell carcinoma were significantly higher in patients with chronic lymphocytic leukemia. Squamous cell carcinomas in patients with chronic lymphocytic leukemia did not exhibit a significant difference in histologic grade or clinical difference in preoperative tumor size. Close surveillance for squamous cell carcinoma recurrence is warranted in patients with chronic lymphocytic leukemia.  相似文献   
2.
A novel animal model of insulin resistance, the fructose-fed Syrian golden hamster has been previously documented to exhibit considerable hepatic very-low-density lipoprotein (VLDL) overproduction concomitant with the development of whole body insulin resistance. Here, we investigated whether hepatic lipoprotein overproduction can be ameliorated by treatment with a hydroxymethyl glutaryl conenzyme A (HMG-CoA) reductase inhibitor, atorvastatin, using a series of ex vivo experiments. Hamsters were fed a fructose-enriched diet for 14 days to induce a state of insulin resistance, and then continued on a fructose-enriched diet supplemented with or without 40 mg/kg atorvastatin per day for 14 days. Fructose feeding in the first 2 weeks caused a significant increase in plasma total cholesterol and triglyceride levels. There was a significant decline in plasma triglyceride levels following supplementation with the inhibitor (50% to 59%; P <.05). Experiments with primary hepatocytes revealed a decreased VLDL-apolipoprotein B (apoB) production (37.4% +/- 10.4%; P <.05) in hamsters treated with atorvastatin. Interestingly, atorvastatin treatment partially attenuated (by 23%) the elevated hepatic level of microsomal triglyceride transfer protein (MTP) induced by fructose feeding. There was molecular evidence of improved hepatic insulin sensitivity with atorvastatin treatment based on assessment of the phosphorylation status of the insulin receptor and the expression of protein tyrosine phosphatase-1B. The improvement in insulin signaling was not mediated by a change in hepatic triglyceride accumulation as no significant difference was observed in liver triglyceride levels. Taken together, these data suggest that statins can ameliorate the VLDL-apoB overproduction state observed in a fructose-fed, insulin-resistant hamster model, and may potentially contribute to an enhanced hepatic insulin sensitivity.  相似文献   
3.
To effectively implement the Canadian Cardiovascular Society (CCS) guidelines for dyslipidemia management into clinical laboratories, clear recommendations for lipid reporting are essential. In this study, the Canadian Society of Clinical Chemists Working Group on Reference Interval Harmonisation surveyed Canadian laboratories on adult lipid reporting practices to set a foundation for the development and implementation of harmonised lipid reporting across Canada. Key aspects of the survey asked laboratories: what reporting parameters were in place to assess lipid results; what interpretative comments were provided; whether nonfasting lipids were permitted and, if so, what strategy was used to document fasting status; and whether there was interest in implementing a harmonised lipid report. A total of 101 laboratories were represented by 24 respondents, as many responses were submitted by laboratory networks that included more than 1 laboratory. There was at least 1 response from 9 Canadian provinces and representation across 5 testing platforms. Upper and lower limits for lipid parameters and referenced source of limits varied substantially across laboratories, with only 56% of laboratories (9 respondents) referencing the 2016 CCS guidelines. Eighty-six percent of laboratories (19 respondents) report nonfasting lipids, although the method of documenting nonfasting status varied. Overall, 36% of laboratories (8 respondents) reported interest in implementing a harmonised lipid report. Assessment of current lipid-reporting practices supports the need for harmonised lipid reporting across Canada. Development of a harmonised lipid report for the adult population, consistent with up-to-date Canadian guidelines, will improve continuity of lipid test interpretation across Canada and improve clinical decision making.  相似文献   
4.
Malignant adenomyoepithelioma (MAME) of the breast is a rare lesion characterized by dual population of epithelial and myoepithelial cells which one or both components show malignant features. We report a case of MAME of the breast in a 46‐year‐old woman diagnosed by fine‐needle aspiration with extensive review of the literature. Classification, clinical presentation, cyto‐pathologic, and immunohistochemical features are described. This lesion showed both malignant components of epithelial and myoepithelial cells in cytology and histology. The malignancy was convincingly supported by high mitotic figures, pleomorphism, and invasion in tissue sections. This review of MAMEs showed that cyto‐histologic diagnosis is difficult and should be supported by immunohistochemical study.  相似文献   
5.

Background

Naltrexone, an opioid receptor antagonist shifts the immune response toward a Th1 profile. In the current study, we evaluated the efficacy of the mixture of NTX and alum, as a new adjuvant, to enhance immune response and induce protection against Leishmania major in a mouse model.

Methods

BALB/c mice were immunized three times either autoclaved L. major promastigotes’ antigens alone or in combination with the adjuvant alum, naltrexone or the alum–naltrexone mixture. Both humoral and cellular immune responses were assessed two weeks after the last immunization and compared with control mice.

Results

The administration of alum- NTX in combination with the parasite antigen, significantly increased production of IFN-γ IFN-γ /IL-5 ratio, lymphocyte proliferation and improved DTH response against L. major. There was no significant difference in survival following challenge among groups.

Conclusion

Immunization with the alum– naltrexone mixture as an adjuvant, in combination with the autoclaved L. major promastigotes antigens, can enhance cellular immunity and shift the immune responses to a Th1 pattern.  相似文献   
6.

Background

Giardia lamblia is one of the most prevalent intestinal flagellate protozoa that infects a wide range of vertebrate hosts causing severe intestinal disorder in children.This study was performed to determine subspecies of G.lamblia by the PCR-RFLP method, targeting the glutamate dehydrogenase(gdh)locus, in hospitalized children at Urmia Mutahhari Hospital, West Azerbaijan Province,Iran and determining the infection transformational storages in this area.

Methods

Overall, 720 stool specimens were collected from the hospitalized children, 34 samples were positive and Giardia cysts were detected under the microscope. Cysts were partially purified by the sucrose density gradient method and then washed with sterile distilled water to remove effectively the PCR inhibitors. Genomic DNA of G. lamblia isolates was extracted by freeze-thaw cycles followed by phenol/ chloroform/isoamyl alcohol method. The single step PCR-RFLP assay was used to differentiate the assemblages between A and B, which were found in humans. In this method, 432 bp expected size was amplified, and then for detection of subspecies, specific restriction RsaI and BspLI enzymes were used.

Results

Totally 34 samples were positive in terms of Giardia cyst out of 720 examined samples microscopically, so the parasite spread rate is reported 4.72%. Analysis PCR-RFLP on these samples revealed that 28 samples (93.3%) have the genotype BIII and 2 samples (6.7%) belong to the subgroup BIV.

Conclusion

PCR-RFLP is a proper analytical method for determining the genotype among parasite types, using the glutamate dehydrogenizes zone’s genes. Based on the results, an animal origin of infection cycle is suggested.  相似文献   
7.
We investigated whether intestinal lipoprotein overproduction in a fructose-fed, insulin-resistant hamster model is prevented with insulin sensitization. Syrian Golden hamsters were fed either chow, 60% fructose for 5 wk, chow for 5 wk with the insulin sensitizer rosiglitazone added for the last 3 wk, or 60% fructose plus rosiglitazone. In vivo Triton studies showed a 2- to 3-fold increase in the large (Svedberg unit > 400) and smaller (Sf 100-400) triglyceride-rich lipoprotein particle apolipoprotein B48 (apoB48) but not triglyceride secretion with fructose feeding in the fasted state (P < 0.01) and partial normalization with rosiglitazone in fructose-fed hamsters. Ex vivo pulse-chase labeling of enterocytes confirmed the oversecretion of apoB48 lipoproteins with fructose feeding. Intestinal lipoprotein oversecretion was associated with increased expression of microsomal triglyceride transfer protein expression. With rosiglitazone treatment of fructose-fed hamsters, there was approximately 50% reduction in apoB48 secretion from primary cultured enterocytes and amelioration of the elevated microsomal triglyceride transfer protein mass and activity in fructose-fed hamsters. In contrast, in the postprandial state, the major differences between nutritional and drug intervention protocols were evident in triglyceride-rich lipoprotein triglyceride and not apoB48 secretion rates. The data suggest that intestinal lipoprotein overproduction can be ameliorated with the insulin sensitizer rosiglitazone.  相似文献   
8.
A series of new hybrids of aspirin (ASA), bearing both nitric oxide (NO) and hydrogen sulfide (H(2)S)-releasing moieties were synthesized and designated as NOSH compounds (1-4). NOSH-1 (4-(3-thioxo-3H-1,2-dithiol-5-yl) phenyl 2-((4-(nitrooxy)-butanoyl)oxy) benzoate); NOSH-2 (4-(nitrooxy)butyl (2-((4-(3-thioxo-3H-1,2-dithiol-5-yl)phenoxy)carbonyl)phenyl)); NOSH-3 (4-carbamothioylphenyl 2-((4-(nitrooxy)butanoyl)-oxy)benzoate); and NOSH-4 (4-(nitrooxy)butyl 2-(5-((R)-1,2-dithiolan-3-yl)pentanoyloxy)-benzoate). The cell growth inhibitory properties of compounds 1-4 were evaluated in eleven different human cancer cell lines of six different tissue origins. These cell lines are of adenomatous (colon, pancreatic, lung, prostate), epithelial (breast), and lymphocytic (leukemia) origin. All NOSH compounds were extremely effective in inhibiting the growth of these cell lines. NOSH-1 was the most potent, with an IC(50) of 48 ± 3 nM in HT-29 colon cancer cells. This is the first NSAID-based compound with such potency. This compound was also devoid of any cellular toxicity, as determined by LDH release. NOSH-1 was comparable to aspirin in its anti-inflammatory properties, using the carrageenan rat paw edema model.  相似文献   
9.
The expression of muscarinic cholinergic receptor subtypes was investigated in peripheral blood lymphocytes (PBL) of bronchial asthma patients by a combined kinetic and equilibrium labeling technique for radioligand binding assay of muscarinic cholinergic receptor subtypes and by receptor immunochemistry and immunocytochemistry. An increased expression of M2 and to a lesser extent of M5 receptors and no changes of M4 receptor were observed in PBL of asthmatics compared to control individuals. The increase was related to bronchial hyperresponsiveness detected by methacholine challenge test. Analysis of M3 receptor expression revealed biphasic changes, with a decreased receptor density in patients with normal, mild and moderate responses to methacholine test and a recovery to levels similar to those found in healthy individuals in severe responders to methacholine test. The demonstration of a different expression of lymphocyte muscarinic receptors in asthma suggests that cholinergic system may participate to a molecular framework influencing immune functions in asthma.  相似文献   
10.
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