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131.
Tetiana Kiriazova Karsten Lunze Anita Raj Natalia Bushara Elena Blokhina Evgeny Krupitsky 《AIDS care》2017,29(5):559-563
Many HIV-positive people who inject drugs (PWID) globally are not receiving HIV care. This represents a major challenge among key populations to end the global HIV epidemic. This qualitative study explored the process and associated barriers of linking HIV-positive PWID who are in addiction treatment to HIV care in St. Petersburg, Russia. We conducted three focus groups and seven semi-structured interviews with participants in the LINC (“Linking Infectious and Narcology Care”) project at addiction and HIV hospitals in St. Petersburg. The sample consisted of 25 HIV-infected patients with opioid dependence and seven health-care providers, including addiction and infectious disease physicians and case managers. A variety of intertwining factors influence effective engagement of PWID with HIV treatment. Stigma, problematic patient–provider relationships, and fragmented health care were the main challenges for HIV care initiation by PWID, which were further exacerbated by injection drug use. Effective linkage of PWID to HIV care requires acknowledging and addressing stigma’s role and different perspectives of patients and providers. 相似文献
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133.
María Julia Lamberti Natalia Belén Rumie Vittar Viviana Alicia Rivarola 《World journal of clinical oncology》2014,5(5):901-907
Photodynamic therapy is a minimally invasive and clinically approved procedure for eliminating selected malignant cells with specific light activation of a photosensitizer agent. Whereas interstitial and intra-operative approaches have been investigated for the ablation of a broad range of superficial or bulky solid tumors such as breast cancer, the majority of approved photodynamic therapy protocols are for the treatment of superficial lesions of skin and luminal organs. This review article will discuss recent progress in research focused mainly on assessing the efficacies of various photosensitizers used in photodynamic therapy, as well as the combinatory strategies of various therapeutic modalities for improving treatments of parenchymal and/or stromal tissues of breast cancer solid tumors. Cytotoxic agents are used in cancer treatments for their effect on rapidly proliferating cancer cells. However, such therapeutics often lack specificity, which can lead to toxicity and undesirable side effects. Many approaches are designed to target tumors. Selective therapies can be established by focusing on distinctive intracellular (receptors, apoptotic pathways, multidrug resistance system, nitric oxide-mediated stress) and environmental (glucose, pH) differences between tumor and healthy tissue. A rational design of effective combination regimens for breast cancer treatment involves a better understanding of the mechanisms and molecular interactions of cytotoxic agents that underlie drug resistance and sensitivity. 相似文献
134.
135.
Nicole A. Najor Lauren Albrecht Natalia Malchin Tomer Goldsmith Meital Grafi‐Cohen Dan Vodo Gilad Fainberg Benjamin Meilik Ilan Goldberg Emily Warshauer Tova Rogers Sarah Edie Akemi Ishida‐Yamamoto Lisa Burzenski Noam Erez Steve A. Murray Alan D. Irvine Lenny Shultz Kathleen J. Green Jouni Uitto Eli Sprecher Ofer Sarig 《Experimental dermatology》2017,26(5):423-430
SVEP1 is a recently identified multidomain cell adhesion protein, homologous to the mouse polydom protein, which has been shown to mediate cell‐cell adhesion in an integrin‐dependent manner in osteogenic cells. In this study, we characterized SVEP1 function in the epidermis. SVEP1 was found by qRT‐PCR to be ubiquitously expressed in human tissues, including the skin. Confocal microscopy revealed that SVEP1 is normally mostly expressed in the cytoplasm of basal and suprabasal epidermal cells. Downregulation of SVEP1 expression in primary keratinocytes resulted in decreased expression of major epidermal differentiation markers. Similarly, SVEP1 downregulation was associated with disturbed differentiation and marked epidermal acanthosis in three‐dimensional skin equivalents. In contrast, the dispase assay failed to demonstrate significant differences in adhesion between keratinocytes expressing normal vs low levels of SVEP1. Homozygous Svep1 knockout mice were embryonic lethal. Thus, to assess the importance of SVEP1 for normal skin homoeostasis in vivo, we downregulated SVEP1 in zebrafish embryos with a Svep1‐specific splice morpholino. Scanning electron microscopy revealed a rugged epidermis with perturbed microridge formation in the centre of the keratinocytes of morphant larvae. Transmission electron microscopy analysis demonstrated abnormal epidermal cell‐cell adhesion with disadhesion between cells in Svep1‐deficient morphant larvae compared to controls. In summary, our results indicate that SVEP1 plays a critical role during epidermal differentiation. 相似文献
136.
Peran L Camuesco D Comalada M Nieto A Concha A Diaz-Ropero MP Olivares M Xaus J Zarzuelo A Galvez J 《World journal of gastroenterology : WJG》2005,11(33):5185-5192
AIM: To investigate the intestinal anti-inflammatory effect and mechanism of a probiotic Lactobacillus salivarius ssp. salivarius CECT5713 in the TNBS model of rat colitis. METHODS: Female Wistar rats (180-200 g) were used in this study. A group of rats were administered orally the probiotic L. salivarius ssp. salivarius(5×108 CFU suspended in 0.5 mL of skimmed milk) daily for 3 wk. Two additional groups were used for reference, a non-colitic and a control colitic without probiotic treatment, which received orally the vehicle used to administer the probiotic. Two weeks after starting the experiment, the rats were rendered colitic by intracolonic administration of 10 mg of TNBS dissolved in 0.25 mL of 500 mL/L ethanol. One week after colitis induction, all animals were killed and colonic damage was evaluated both histologically and biochemically. The biochemical studies performed in colonic homogenates include determination of myeloperoxidase (MPO) activity, glutathione (GSH) content, leukotriene B4 (LTB4) and tumor necrosis factor a (TNF-α) levels, as well as inducible nitric oxide synthase (iNOS) expression. In addition, the luminal contents obtained from colonic samples were used for microbiological studies, in order to determine Lactobacilli and Bifidobacteria counts. RESULTS: Treatment of colitic rats with L salivarius ssp. salivarius resulted in amelioration of the inflammatory response in colitic rats, when compared with the corresponding control group without probiotic treatment. This anti-inflammatory effect was evidenced macroscopically by a significant reduction in the extent of colonic necrosis and/or inflammation induced by the administration of TNBS/ethanol (2.3±0.4 cm vs 53.4±0.3 cm in control group, P<0.01) and histologically by improvement of the colonic architecture associated with a reduction in the neutrophil infiltrate in comparison with non-treated colitic rats. The latter was confirmed biochemically by a significant reduction of colonic MPO activity (105.3±26.0 U/g vs 180.6±21.9 U/g, P<0.05) a marker of neutrophil infiltration. The beneficial effect was associated with an increase of the colonic GSH content (1 252±42 nmol/g vs 1 087±51 nmol/g,P<0.05), which is depleted in colitic rats, as a consequence of the oxidative stress induced by the inflammatory process. In addition, the treatment of colitic rats with L. salivarius resulted in a significant reduction of colonic TNF-α levels (509.4±68.2 pg/g vs 782.9±60.1 pg/g, P<0.01) and in a lower colonic iNOS expression, when compared to TNBS control animals without probiotic administration. Finally, treated colitic rats showed higher counts of Lactobacilli species in colonic contents than control colitic rats, whereas no differences were observed in Bifidobacteria counts. CONCLUSION: Administration of the probiotic L. salivarius ssp. salivarius CECT5713 facilitates the recovery of the inflamed tissue in the TNBS model of rat colitis, an effect associated with amelioration of the production of some of the mediators involved in the inflammatory response in the intestine, such as cytokines, including TNF-α and NO. This beneficial effect could be ascribed to its effect on the altered immune response that occurs in this inflammatory condition. 相似文献
137.
Newton PN Hampton CY Alter-Hall K Teerwarakulpana T Prakongpan S Ruangveerayuth R White NJ Day NP Tudino MB Mancuso N Fernández FM 《The American journal of tropical medicine and hygiene》2008,79(5):662-669
Multidrug-resistant Plasmodium falciparum malaria is a severe public health problem on the Thailand-Myanmar border. Many villagers buy packets of 4-5 mixed medicines ("yaa chud") from shops without medical assessment as their first-line malaria treatment. In 2000-2001 a local researcher purchased 50 yaa chud from 44 shops around Mae Sot, Thailand and Myawaddy, Myanmar (Burma), for his wife who was said to be pregnant with fever and drowsiness. The tablets/capsules were provisionally identified by appearance and active ingredients determined in a subset by using mass and atomic spectrometry. The most frequently detected active ingredients were acetaminophen (22%), chlorpheniramine (13.4%), chloroquine (12.6%), tetracycline/doxycycline (11.4%), and quinine (5.1%). Only seven bags contained potentially curative medicine for malaria. A total of 82% of the bags contained medicines contraindicated in pregnancy. Inappropriate, ineffective antimalarial drugs on the Thailand-Myanmar border are likely to increase malaria morbidity, mortality and health costs and engender the emergence and spread of antimalarial drug resistance. 相似文献
138.
Irabuena O Nieto A Ferreira AM Battistoni J Ferragut G 《Revista do Instituto de Medicina Tropical de S?o Paulo》2000,42(5):255-262
The aim of this work was to assess the influence in the diagnostic value for human hydatid disease of the composition of bovine hydatid cyst fluid (BHCF) obtained from fertile (FC) and non-fertile cysts (NFC). Eight batches from FC and 5 from NFC were prepared and analysed with respect to chemical composition: total protein, host-derived protein, carbohydrate and lipid contents. No differences were observed in the first two parameters but carbohydrate and lipid contents were shown to be higher in batches from FC than in those from NFC. Bands of 38 and 116 kD in SDS-PAGE profiles were observed to be present in BHCF from FC only. Two pools were prepared from BHCF batches obtained from FC (PFC) and NFC (PNFC), respectively. Antigen recognition patterns were analysed by immunoblot. Physicochemical conditions for adsorption of antigens to the polystyrene surface (ELISA plates) were optimized. The diagnostic value of both types of BHCF as well as the diagnostic relevance of oxidation of their carbohydrate moieties with periodate were assessed by ELISA using 42 serum samples from hydatid patients, 41 from patients with other disorders, and 15 from healthy donors. Reactivity of all sera against native antigen were tested with and without free phosphorylcholine. The best diagnostic efficiency was observed using BHCF from periodate-treated PFC using glycine buffer with strong ionic strength to coat ELISA plates. 相似文献
139.
Fridman AI Matveev SA Agalakova NI Fedorova OV Lakatta EG Bagrov AY 《Journal of hypertension》2002,20(6):1189-1194
BACKGROUND : A reduced cardiac output in chronic heart failure (CHF) evokes renal NaCl and water retention, and, therefore, activates mechanisms promoting natriuresis. Atrial natriuretic peptide (ANP) is one such factor. We hypothesized that another NaCl sensitive endogenous natriuretic factor, i.e., marinobufagenin (MBG), a specific ligand of the alpha-1 subunit of Na/K ATPase (the main kidney isoform) and also a vasoconstrictor and cardiotonic substance, would be elevated in CHF patients in a graded manner with the severity of CHF. METHODS AND RESULTS : We measured the plasma levels of MBG, alpha-hANP, ouabain-like compound (OLC) and left ventricular (LV) volumes and ejection fraction in 23 consecutive hypertensive male patients with CHF. Plasma MBG levels exhibited progressive increases (0.59 +/- 0.15, 1.08 +/- 0.20, 1.35 +/- 0.17 and 1.88 +/- 0.05 nmol/l NYHA 1-4, respectively) and paralleled the changes of alpha-hANP. Conversely, plasma OLC did not exhibit such increases. Plasma MBG correlated with alpha-hANP (r = 0.82; P < 0.0001). Both MBG and alpha-hANP correlated with LV systolic (r = 0.55 and r = 0.47; P < 0.01) diameter and inversely with ejection fraction (r = -0.73 and r = -0.60; P < 0.01). OLC did not exhibit correlations with alpha-hANP or LV volumes, but positively correlated with systolic brachial blood pressure and with pulse pressure. CONCLUSIONS : In CHF, MBG exhibits progressive increases similar to ANP, varies with CHF severity and correlates with LV systolic function. We hypothesize, that, in CHF, the concurrent production of these two natriuretic hormones, a vasorelaxant, ANP, and a vasoconstrictor, MBG, potentiate each other's natriuretic effects, but may offset their vasoactive actions. 相似文献
140.
Gutman JA Bearman SI Nieto Y Sweetenham JW Jones RB Shpall EJ Zeng C Baron A McSweeney PA 《Bone marrow transplantation》2005,36(5):443-451
We report outcomes in advanced lymphoma patients (n = 32) who enrolled in a trial of prospectively planned combined autologous/reduced-intensity transplantation (RIT) (n = 25) or who received RIT shortly after prior autografting because of high relapse risk or progressive disease (n = 7). Nine patients on the autologous/RIT transplant protocol did not proceed to planned RIT because of patient choice (n = 4), disease progression (n = 3), toxicity (n = 1), or no adequate donor (n = 1). Among the 23 other patients, RIT was started a median of 59 days (range 31-123) after autologous transplant. Fifteen patients had related donors, five patients had unrelated donors, and three patients had cord blood donors. Among all patients completing RIT, the median overall survival time was 385 days (95% CI 272-792), and the median relapse-free survival time was 157 days (95% CI 119-385). At the time of reporting, six patients (26%) remain alive and three patients (13%) remain alive without relapse. The 100-day transplant-related mortality (TRM) was 9% among all patients and was 0% among matched sibling donors. Overall TRM was 43%. Tandem transplant is feasible in advanced lymphoma with low early TRM. However, practical challenges associated with the strategy were significant and high levels of late TRM due to graft-versus-host disease and infections suggest that modifications of the procedure will be needed to improve outcomes and patient retention. 相似文献