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81.
We studied the seroprevalence of antibodies against Trypanosoma cruzi in the human population along with domiciliary infestation by triatomine bugs in an area endemic for Chagas disease in the Chaco Province of Argentina. In addition, we carried out parasitologic surveys in patients, dogs, wild mammals, and vectors. The mean seroprevalence in humans was 27.81% (109 of 392) and 24.14% (63 of 261) in 1-15-year-old children. The minimum domiciliary infestation rate was 13.33%, with certain areas reaching 53.85%. The prevalence was 15.09% (16 of 106) in dogs and 35.71% (10 of 28) in opossums. Infection with T. cruzi was detected in 30.10% (59 of 196) of the Triatoma infestans tested. Compared with nationwide studies, our data suggest that 1) there are zones requiring immediate sanitary action, and 2) nationwide estimates are based on very heterogeneous epidemiologic situations. This heterogeneity emphasizes the importance of in-depth studies of restricted areas to provide additional information for a better understanding of the present status of Chagas disease in Argentina.  相似文献   
82.
The objective of the study was to determine the degree of linear growth retardation of patients with vitamin D deficiency rickets at presentation and the magnitude of catch-up growth in relation to their calcium (Ca) homeostasis and hormones affecting it before and after treatment. This prospective study recorded the anthropometric data and measured the circulating 25-hydroxy vitamin D (25-OH-D), insulin-like growth factor I (IGF-I), parathyroid hormone, Ca, phosphate, and alkaline phosphatase concentrations in 46 infants and children with nutritional (vitamin D deficiency) rickets before and 6 months or more after treatment with one intramuscular injection of vitamin D3 megadose (300000 IU). Forty normal age- and sex-matched children were included as controls for the auxological data. At presentation, patients' mean age = 13.1 +/- 1.1 months, length standard deviation scores (LSDS) = -1.5 +/- 0.2, and body mass index = 16.3 +/- 0.85. They were significantly shorter and had markedly lower growth velocity standard deviation scores (GVSDS) compared with normal controls (LSDS = 0.25 +/- 0.18 and 0.31 +/- 0.22, respectively). Six months after treatment, the LSDS increased significantly in patients to -0.45 +/- 0.13, with a significantly increased GVSDS (2.76 +/- 0.45) and body mass index (16.9 +/- 0.65). They were still shorter but with significantly higher GVSDS compared with normal controls. Serum Ca and phosphate concentrations increased from 2.07 +/- 0.25 and 1.23 +/- 0.24 mmol/L, respectively, before treatment to 2.44 +/- 0.2 and 1.94 +/- 0.2 mmol/L, respectively, after treatment. Serum alkaline phosphatase and parathyroid hormone concentrations decreased from 1183 +/- 219 U/L and 294 +/- 87 pg/mL, respectively, before treatment to 334 +/- 75 U/L and 35.2 +/- 15.2 pg/mL, respectively, after treatment. The 25-OH-D level increased from 4.5 +/- 0.56 ng/mL before treatment to 44.5 +/- 3.7 ng/mL after treatment. Circulating concentrations of IGF-I increased significantly after treatment (52.2 +/- 18.9 ng/mL) vs before treatment (26.6 +/- 12.8 ng/mL). The 25-OH-D concentrations were correlated significantly with the IGF-I levels before and after treatment (r = 0.603 and r = 0.59, respectively; P < .001). The GVSDS after treatment was correlated with the increase of IGF-I and 25-OH-D levels (r = 0.325 and r= 0.314, respectively; P < .01). These data denote that the accelerated linear growth after treatment of nutritional vitamin D deficiency is mediated through activation of the growth hormone/IGF-I system and suggests an important role of vitamin D as a link between the proliferating cartilage cells of the growth plate and growth hormone/IGF-I secretion. Three different sequential stages of vitamin D deficiency can be recognized according to the clinical/radiological, biochemical, and hormonal data of patients at presentation.  相似文献   
83.
Semmo N  Barnes E  Taylor C  Kurtz J  Harcourt G  Smith N  Klenerman P 《Lancet》2005,365(9456):327-329
Blood donors are routinely screened for hepatitis C virus infection. Some individuals have weak or restricted virus-specific antibody responses, and are classed as indeterminate. Such donors are almost always negative for viral RNA in blood. We postulated that previous transient virus exposure might account for some of these cases. With sensitive ex-vivo analyses of T-cell responses, we identified virus-specific responses in 15 of 30 indeterminate blood donors tested, compared with none in controls (p=0.0013). Additionally, these responses were typically focused on core-derived peptides. These findings suggest previous exposure to the virus in many indeterminate blood donors.  相似文献   
84.

Purpose of Review

The purpose of this review is to examine the impact and effectiveness of community interventions for controlling hypertension in African-Americans. The questions addressed are as follows: Which salient prior and current community efforts focus on African-Americans and are most effective in controlling hypertension and patient-related outcomes? How are these efforts implemented and possibly sustained?

Recent Findings

The integration of out-of-office blood pressure measurements, novel hypertension control centers (i.e., barbershops), and community health workers improve hypertension control and may reduce the excess hypertension-related complications in African-Americans. Several community-based interventions may assist effectiveness of clinical care teams, decrease care barriers, and improve adherence.

Summary

A multifaceted, tailored, multidisciplinary community-based approach may effectively reduce barriers to blood pressure control among African-Americans. Future research should evaluate the long-term benefits of community health workers, barbershops as control centers, and out-of-office blood pressure monitoring upon control and eventually on morbidity and mortality.
  相似文献   
85.
Patient safety is a fundamental aspect of a healthcare system. The aim of this study was to assess the perception and determinants of the patient safety culture of pharmacists in hospitals, in Riyadh, Saudi Arabia.A survey was conducted with pharmacists in the pharmacies of governmental, /military and private hospitals in Riyadh, Saudi Arabia. The pharmacy survey on patient safety culture questionnaire developed by Agency for Healthcare Research and Qualtity, a hard copy was distriuted to the pharmacists. The positive response rate (RR) was calculated and compared across hospitals using a chi-square test. The predictors of patient safety grades were identified using the generalized estimating equation. The data was analyzed using SAS.A total of 538 questionnaires were distributed, of which 411 responded (RR 76.4%). Of the participants, 229 (56%) were females. The majority 255 (62%) were in the 18 to 34 years age range, and 361 (88%) had a bachelor''s degree. The majority of the sample 376 (92%) was a pharmacist. The Positive RR (PRR) ranged between (25.6%–74%). The highest PRR was observed in teamwork (74.4%), followed by ‘staff, training and skills’ (68%), and ‘organizational learning continuous improvement’ (66%). The lowest PRR was observed in ‘staffing, work pressure, and pace’ (25.5%). Comparing the PPR of the various healthcare sectors, the governmental hospitals scored the highest in all patient safety domains. Generalized Estimating Equation analysis showed that with increase in scores of all patient safety culture domains increased the likelihood of reporting a better patient safety grade, whereas respondents’ demographic characteristics had no effect except the working experience years 6 years and above had odds of poor reporting of the patient safety grade (odds ratio = 2.54, 95% confience interval (1.543, 4.194), (P = .0003).The grades achieved in the various domains of patient safety culture by pharmacists in Riyadh are below the expected standard. The highest scores were achieved in teamwork, with the lowest scores in staffing, work pressure and pace. Overall, pharmacists in government hospital settings have a better perception of patient safety than their peers in other settings. These results provide the baseline evidence for developing future interventional studies aiming at improving patient safety culture in hospital pharmacy settings.  相似文献   
86.

Background

Nanoparticles (NPs) play an important role in anticancer delivery systems. Surface modified NPs with hydrophilic polymers such as human serum albumin (HSA) have long half-life in the blood circulation system.

Methods

The method of modified nanoprecipitation was utilized for encapsulation of paclitaxel (PTX) in poly (lactic-co-glycolic acid) (PLGA). Para-maleimide benzoic hydrazide was conjugated to PLGA for the surface modifications of PLGA NPs, and then HSA was attached on the surface of prepared NPs by maleimide attachment to thiol groups (cysteines) of albumin. The application of HSA provides for the longer blood circulation of stealth NPs due to their escape from reticuloendothelial system (RES). Then the physicochemical properties of NPs like surface morphology, size, zeta potential, and in-vitro drug release were analyzed.

Results

The particle size of NPs ranged from 170 to 190 nm and increased about 20–30 nm after HSA conjugation. The zeta potential was about -6 mV and it decreased further after HSA conjugation. The HSA conjugation in prepared NPs was proved by Fourier transform infrared (FT-IR) spectroscopy, faster degradation of HSA in Differential scanning calorimetry (DSC) characterization, and other evidences such as the increasing in size and the decreasing in zeta potential. The PTX released in a biphasic mode for all colloidal suspensions. A sustained release profile for approximately 33 days was detected after a burst effect of the loaded drug. The in vitro cytotoxicity evaluation also indicated that the HSA NPs are more cytotoxic than plain NPs.

Conclusions

HSA decoration of PLGA NPs may be a suitable method for longer blood circulation of NPs.  相似文献   
87.
Clinical Rheumatology - Coronavirus disease-19 (COVID-19) is a global pandemic that is caused by COVID-19 virus, which was initially identified in December 2019 in Wuhan, China. Vaccination is one...  相似文献   
88.
The aim of this study was to evaluate the use of different fixatives on the reliability of histopathological changes in a rabbit model of proliferative vitreoretinopathy (PVR). Twenty eyes from 10 rabbits were divided into four groups. The right eyes were used in two experimental groups (each n = 5), and the left, in two control groups (each n = 5). Using a newly developed scleral incision marker, an oblique scleral incision was standardized in the experimental groups, followed by intravitreal injection of 0.4 ml autologous blood and the left for wound repair for four weeks. Eyes were enucleated at four weeks. The groups differed in the type of used fixative solution (formaldehyde 4% vs. 1% buffered formaldehyde and 1.25% glutaraldehyde). The eyes were evaluated for the development of fibrosis, retinal detachment (RD), and processed for histopathology. Fibrous ingrowth of a variable degree was present in the experimental groups originating from the trauma site. Experimental eyes fixed with formaldehyde 4% had RD extension that was greater than that fixed in formaldehyde/glutaraldehyde mixture; however, the difference did not reach statistical significance (P = 0.15). This difference was not fully explained by the fibrosis which developed. In addition, in control groups, formaldehyde 4% induced a fixative-dependent retinal separation that was absent in eyes fixed with formaldehyde/glutaraldehyde mixture (P = 0.03). In conclusion, a mixture of buffered formaldehyde 1% and glutaraldehyde 1.25% combined with standardized scleral incision resulted in consistent pathological changes. A reliable PVR model is a condition sine qua non to evaluate antifibrotic treatment strategies.  相似文献   
89.
90.
Resistance toward imatinib and other BCR/ABL tyrosine kinase inhibitors remains an increasing clinical problem in the treatment of advanced stages of chronic myeloid leukemia (CML). We recently have identified the heat shock protein 32 (Hsp32)/heme oxygenase-1 (HO-1) as a BCR/ABL-dependent survival molecule in CML cells. We here show that silencing Hsp32/HO-1 in CML cells by an siRNA approach results in induction of apoptosis. Moreover, targeting Hsp32/HO-1 by either pegylated zinc protoporphyrine (PEG-ZnPP) or styrene maleic acid-micelle-encapsulated ZnPP (SMA-ZnPP) resulted in growth inhibition of BCR/ABL-transformed cells. The effects of PEG-ZnPP and SMA-ZnPP were demonstrable in Ba/F3 cells carrying various imatinib-resistant mutants of BCR/ABL, including the T315I mutant, which exhibits resistance against all clinically available BCR/ABL tyrosine kinase inhibitors. Growth-inhibitory effects of PEG-ZnPP and SMA-ZnPP also were observed in the CML-derived human cell lines K562 and KU812 as well as in primary leukemic cells obtained from patients with freshly diagnosed CML or imatinib-resistant CML. Finally, Hsp32/HO-1-targeting compounds were found to synergize with either imatinib or nilotinib in producing growth inhibition in imatinib-resistant K562 cells and in Ba/F3 cells harboring the T315I mutant of BCR/ABL. In summary, these data show that HO-1 is a promising novel target in imatinib-resistant CML.  相似文献   
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