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51.
Leishmania (Viannia) braziliensis, a protozoan parasite widespread in the New World, is responsible for the infection of different mammal orders, including humans. This species is considered to be a major etiological agent of American cutaneous leishmaniasis. A proteomic study was carried out to identify proteins expressed by L. (V.) braziliensis. One hundred and one spots representing 75 protein entries were identified by MALDI-TOF-TOF. Isoelectric point values estimated by gel electrophoresis matched closely with predicted values, although some discrepancies existed suggesting that post-translational protein modifications may be common in L. braziliensis. Moreover, 20 hypothetical proteins were experimentally identified. Identified proteins were classified into 15 groups according to biological process. Among the proteins identified, approximately 40% have not been previously reported in a proteomic map of Leishmania. In addition, a number of potential virulence factors and drug targets were identified in this protein map, including some proteins associated with the metastatic phenotype. This study describes the first compilation of a proteomic reference map for L. braziliensis (pI 4-7, M(r) 10-130 kDa) and provides a very useful tool for comparative studies of strains isolated from patients presenting different clinical manifestations of leishmaniasis as well as a potential tool to identify markers for clinical diagnosis, therapeutics, and prognosis.  相似文献   
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The cytomegalovirus (CMV) antigenemia assay has been used frequently for rapid diagnosis of CMV infection, and antigenemia threshold values are recommended for triggering preemptive therapy. Hybrid capture of CMV's DNA and quantitative polymerase chain reaction (qPCR) are increasingly being adopted for early detection of CMV. The performance of the antigenemia assay, qPCR in plasma and hybrid capture in leukocytes were compared in 110 immunocompromised patients (38 bone-marrow transplants, 50 renal transplants and 22 AIDS patients). The most sensitive test was hybrid capture for transplants, while antigenemia and the qPCR showed similar performance for patients with AIDS. QPCR and hybrid capture thresholds requiring antiviral therapy were calculated using a receiver-operating-characteristic curve for antigenemia values corresponding to 2 positive cells for bone-marrow transplants and to 10 positive cells for renal transplants and AIDS patients. These threshold values varied with the group of patients considered, with corresponding sensitivities higher than 86% and specificities higher than 76% for hybrid capture, and sensitivities higher than 61% and specificities higher than 75% for qPCR in plasma. Hybrid capture in leukocytes can substitute for antigenemia in the case of transplants, and qPCR in plasma can substitute for it in the case of AIDS patients.  相似文献   
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Background and objectives

Comparisons of predictive performance of various anthropometric measures in high blood pressure have not been investigated. This study aimed at evaluating and comparing the predictive power of Body Mass Index (BMI), Body Adiposity index (BAI) and A Body Shape Index (ABSI) for predicting hypertension in adults.

Methods

The data of 277 subjects (109 men and 168 women) as a part of the major Lifestyle Promotion Project (LPP) conducted in the districts of Tabriz-East Azerbaijan-Iran were collected for this study. The weight, height, waist and hip circumferences were measured and BMI, BAI and ABSI were calculated. Blood pressure was measured twice, after 5 minutes of rest. The ANOVA and Receiver Operating Characteristic (ROC) were used for statistical analysis.

Results

In all subjects, BMI (area under the curve (AUC): 0.65) predicted systolic blood pressure equally (P < 0.05). None of them had a significant prediction for diastolic blood pressure. By gender, considering P-value (P < 0.05), BMI predicted systolic in men (AUC: 0.71) and women (AUC: 0.61) and diastolic blood pressure only in men (AUC: 0.79). In addition systolic blood pressure in women was predicted by both BAI (AUC: 0.66) and ABSI (AUC: 0.67). Furthermore, BAI (AUC: 0.82) predicted diastolic blood pressure in men.

Conclusion

Although it was claimed that ABSI and BAI as the indexes of high waist circumference and body fat percent respectively, express the excess risk, based on our results, they are not better alternative than BMI in the clinical evaluation for screening for high blood pressure.  相似文献   
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Demineralization of enamel around orthodontic brackets is a clinical problem which can lead to some esthetic concerns like white spot lesions. The aim of this in vitro study was to evaluate the effect of the Er, Cr:YSGG laser and fluoride application on the acid resistance of enamel adjacent to orthodontic brackets. A total of 60 healthy, permanent, human premolars were selected and bonded with brackets, then they were randomly assigned to four groups (n?=?15): topical APF gel (1.23 % F, pH 3.5, for 4 min); Er,Cr:YSGG laser (P:0.25 W, E:12.5 mJ, RR:20 Hz, PD:140 μs, 11 % air, without water, for 10 s); fluoride + laser group (F + L), and control group (C). All specimens were demineralized for 10 days in a 0.2 M acetate buffer solution, and the calcium content were subsequently determined with atomic absorption spectrometry. There were significant differences between the calcium content of F + L and F group in comparison to control group. The least concentration of calcium was seen in F + L group, and the most value was observed in C group. Combination of Er, Cr:YSGG laser with fluoride and fluoride alone decreased enamel solubility significantly more than laser alone. In addition, combination of laser and fluoride leads to less consumption of fluoride amount. And patients can use it at the beginning of treatment instead of daily use of fluoride. So we suggest using it in preventing enamel demineralization around orthodontic brackets.  相似文献   
58.
Spider venoms contain neurotoxic peptides aimed at paralyzing prey or for defense against predators; that is why they represent valuable tools for studies in neuroscience field. The present study aimed at identifying the process of internalization that occurs during the increased trafficking of vesicles caused by Phoneutria nigriventer spider venom (PNV)-induced blood–brain barrier (BBB) breakdown. Herein, we found that caveolin-1α is up-regulated in the cerebellar capillaries and Purkinje neurons of PNV-administered P14 (neonate) and 8- to 10-week-old (adult) rats. The white matter and granular layers were regions where caveolin-1α showed major upregulation. The variable age played a role in this effect. Caveolin-1 is the central protein that controls caveolae formation. Caveolar-specialized cholesterol- and sphingolipid-rich membrane sub-domains are involved in endocytosis, transcytosis, mechano-sensing, synapse formation and stabilization, signal transduction, intercellular communication, apoptosis, and various signaling events, including those related to calcium handling. PNV is extremely rich in neurotoxic peptides that affect glutamate handling and interferes with ion channels physiology. We suggest that the PNV-induced BBB opening is associated with a high expression of caveolae frame-forming caveolin-1α, and therefore in the process of internalization and enhanced transcytosis. Caveolin-1α up-regulation in Purkinje neurons could be related to a way of neurons to preserve, restore, and enhance function following PNV-induced excitotoxicity. The findings disclose interesting perspectives for further molecular studies of the interaction between PNV and caveolar specialized membrane domains. It proves PNV to be excellent tool for studies of transcytosis, the most common form of BBB-enhanced permeability.  相似文献   
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Background and aimsDiabetic foot ulcers (DFUs) are among challenging hurdles both for the patient and the physician. There is a recent trend toward finding novel and clinically efficient modalities to treat this potentially hazardous complication of diabetes mellitus in a timely manner. Herein, we aim to appraise the efficacy of platelet-rich plasma (PRP) in healing of clean DFUs.Methods90 patients with clean DFUs consisting of 56 (62.2%) males and 34 (37.8%) females with mean age (±standard deviation) of 56.52 (±7.14) years were enrolled in this study between June 2017 and December 2018. They were randomly allocated into control group (47 patients who received conventional dressing along with silver sulfadiazine ointment twice daily), and case group (43 patients who received PRP gel twice weekly for 3 weeks). All the patients were followed up for 6 months.ResultsOur study showed that PRP significantly increased the healing rate of DFUs regardless of the age (p-value: 0.0), gender (p-value: 0.0), or smoking (p-value: 0.0) and blood pressure (p-value: 0.0) status of patients, but it did not have a significant impact on the need for amputation (p-value: 0.11), level of amputation (p-value: 0.16), or the need for further treatments such as graft or angioplasty (p-value: 0.52).ConclusionRegardless of the age, gender, or smoking and blood pressure status of patients, PRP can be efficiently used in diabetic patients to accelerate the healing rate of foot ulcers.  相似文献   
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