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31.
Lee Emerson E. Gong Anna J. Gawande Rakhee S. Fishman Elliot K. Vadvala Harshna V. 《Emergency radiology》2022,29(2):263-279
Emergency Radiology - The purpose of our review is to discuss the role of CT angiography (CTA) in evaluating a variety of vascular complications in critically ill COVID-19 patients. The COVID-19... 相似文献
32.
da Silva ER Sly PD de Pereira MU Pinto LA Jones MH Pitrez PM Stein RT 《Pediatric pulmonology》2008,43(7):662-665
Non-atopic asthma is the predominant phenotype in non-affluent parts of Latin America. We recently reported that infestation with Ascaris lumbricoides increased the risk of non-atopic asthma in less affluent areas of Brazil but the mechanism is unclear. The present study was conducted to determine whether helminth infestation is associated with heightened bronchial responsiveness (BHR), a common finding in asthma. A random sample of 50 asthmatic and 50 non-asthmatic controls (mean age 10.1 years) were selected from a larger cohort (n = 1,011) without knowledge of their helminth infestation status. Three stool samples were collected from each child on different days and each sample was analyzed by the Kato-Katz method for quantitative determination of helminth eggs. Bronchial provocation tests were performed with inhaled 4.5% hypertonic saline using the ISAAC Phase II standardized protocol. There was no difference between the prevalence of positive BHR in the asthmatics (20.4%) compared with the controls (14.6%) (P = 1.0). Helminth infestation was detected in 24.0% of children, with A. lumbricoides being the most common. Children with high load infestation (>or=100 eggs/g) were five times more likely to have BHR than children with low load or no infestation. Despite the small sample size the results of the present study suggest that the link between high load helminth infestation and non-atopic asthma may be mediated via heightened bronchial responsiveness, possibly due to an inflammatory response to the pulmonary phase of the helminth life cycle. 相似文献
33.
The placenta contains iodothyronine 5-deiodinase activity (P5-Dase) that probably acts on iodothyronines in the fetal circulation to convert T4 to rT3 and T3 to 3,3'-T2. Since thyroid status and fasting have profound effects on iodothyronine deiodinases in other tissues, the present studies were performed to determine if these perturbations affected P5-Dase. Control and treated rats were mated and killed near term on the 20th day of gestation. P5-Dase was determined in placenta homogenates enriched with dithiothreitol by measuring the conversion of T4 to rT3. In four of five studies, P5-Dase was similar in dams that underwent thyroidectomy (Tx) on day 7 of gestation and sham Tx dams. P5-Dase was not altered in dams that were treated with methimazole (MMI) to induce maternal and fetal hypothyroidism. Treatment of dams with supraphysiological doses of T4, beginning on the seventh day of gestation, did not significantly affect P5-Dase. In three of four studies, P5-Dase was similar in fed dams to values in dams fasted for the last 5 days of pregnancy. Placenta iodothyronine 5'-deiodinase activity (P5'-Dase) was also measured in some studies. P5'-Dase was not decreased in Tx rats and was modestly decreased in MMI-treated rats. However, the effect of MMI was not reversed by the administration of supraphysiological doses of T4, Tx, MMI treatment, and fasting all decreased hepatic T4 5'-deiodinase activity in pregnant rats. These results strongly suggest that thyroid status and fasting do not alter P5-Dase activity. 相似文献
34.
Guilherme V. Silva Emerson C. Perin James T. Willerson 《Current cardiovascular risk reports》2008,2(5):342-349
Cardiac repair with cell-based therapy is a promising treatment for patients with coronary heart disease. Preclinical and
early clinical studies have shown that stem cell therapy is safe and effective in improving left ventricular function and
myocardial perfusion. Specifically, cardiac stem cell therapy may be beneficial in reducing left ventricular remodeling in
patients with myocardial infarction and in improving symptoms and preventing cardiac enlargement in patients with chronic
ischemic heart disease. Although not well defined, multiple mechanisms, including paracrine effects, probably contribute to
stem cell-mediated cardiac repair. The issues of timing, mode of delivery, and cell dose need to be systematically studied
to maximize benefits. Nevertheless, rapid advancements may soon make cardiac stem cell therapy a central part of the treatment
regimen for patients with coronary heart disease. 相似文献
35.
Changes in house design reduce exposure to malaria mosquitoes 总被引:3,自引:0,他引:3
Lindsay SW Jawara M Paine K Pinder M Walraven GE Emerson PM 《Tropical medicine & international health : TM & IH》2003,8(6):512-517
House design may affect an individual's exposure to malaria parasites, and hence to disease. We conducted a randomized-controlled study using experimental huts in rural Gambia, to determine whether installing a ceiling or closing the eaves could protect people from malaria mosquitoes. Five treatments were tested against a control hut: plywood ceiling; synthetic-netting ceiling; insecticide-treated synthetic-netting ceiling (deltamethrin 12.5 mg/m2); plastic insect-screen ceiling; or the eaves closed with mud. The acceptability of such interventions was investigated by discussions with local communities. House entry by Anopheles gambiae, the principal African malaria vector, was reduced by the presence of a ceiling: plywood (59% reduction), synthetic-netting (79%), insecticide-treated synthetic-netting (78%), plastic insect-screen (80%, P < 0.001 in all cases) and closed eaves (37%, ns). Similar reductions were also seen with Mansonia spp., vectors of lymphatic filariasis and numerous arboviruses. Netting and insect-screen ceilings probably work as decoy traps attracting mosquitoes into the roof space, but not the room. Ceilings are likely to be well accepted and may be of greatest benefit in areas of low to moderate transmission and when used in combination with other malaria control strategies. 相似文献
36.
Isabele C. Angelo Patrícia S. Gôlo Wendell M. S. Perinotto Mariana G. Camargo Simone Quinelato Fillipe A. Sá Emerson G. Pontes Vânia R. E. P. Bittencourt 《Parasitology research》2013,112(2):501-509
The tick’s fat body plays an essential role in energy storage and utilization. This study aimed to analyze the fat body neutral lipid composition in Rhipicephalus microplus engorged females. In the first study (physiological profile of untreated ticks), the lipid analysis took place over the course of 4 days; the engorged females were incubated at optimal conditions and their fat bodies were dissected daily. Fat body lipid analysis after fungal infection with Metarhizium anisopliae sensu lato (s.l.) or Beauveria bassiana s.l. was performed with four groups: one without any treatment, one that was inoculated with a solution of 0.1 % Tween 80 in water, and two groups that were inoculated with M. anisopliae or B. bassiana conidial suspensions. The fat bodies were dissected 24 and 48 h after infection. Lipid analysis was conducted by thin-layer chromatography on a silica plate. The results of the physiological profile showed that the amounts of triacylglycerol (TAG) and free cholesterol (CHO) decreased with time, whereas cholesterol ester (CHOE) increased on the second and fourth days. Following M. anisopliae or B. bassiana infection, there was an increase in the amount of CHO after 24 h, whereas the other lipid classes were not altered. M. anisopliae caused an increase in CHOE and TAG and a reduction in CHO at 48 h after infection; however, B. bassiana infection did not cause significant alterations in the concentrations of these lipids. M. anisopliae and B. bassiana infection changed the fat body metabolism of engorged female R. microplus ticks. This study provides the first report of changes in the neutral lipid composition of the R. microplus fat body. 相似文献
37.
Camila P. Almeida Camila O. Silveira Enio F. Ferreira Marcia C. Ferreira Gabriella G. Oliveira Emerson S. Veloso Felipe H.S. Silva Santuza S. Coelho Leonardo M. Moraes Fernando M. Reis Helen L. Del Puerto 《Acta histochemica》2021,123(2):151670
Apoptosis regulation in luteinized granulosa cells (LGC) during assisted reproduction procedures is still controversial. Caspase-3 is a major apoptosis mediator encoded by CASP3 and formed through cleavage of its precursor pro-caspase-3. The aim of this study was to investigate the expression patterns of pro-caspase-3 (mRNA and protein) and cleaved caspase-3 in human LGC. Thirty-five women undergoing controlled ovarian stimulation for in vitro fertilization were prospectively enrolled in the study. LGC were isolated from follicular fluid during oocyte pickup and evaluated by immunocytochemistry for pro-caspase-3 and cleaved caspase-3, and by real-time PCR for CASP3 mRNA expression. We found a positive staining of pro-caspase-3 in 77 % of the LGC (95 % confidence interval [CI] 60%–84%), whereas cleaved caspase-3 was found in only 4% of the cells (95 % CI 3%–6%). The abundance of cells expressing pro-caspase-3 was independent from CASP3 mRNA levels (r = 0.24, p = 0.255) and did not correlate with the amount of cleaved caspase-3 (r = -0.24, p = 0.186). Multivariable logistic regression showed that pro-caspase-3 positivity was not influenced by clinical characteristics such as age, cause or length of infertility, antral follicle count or hormonal drugs used to induce ovulation. These findings suggest that pro-caspase-3 is constitutively expressed in LGC, allowing quick cleavage into active caspase-3 and apoptosis triggering whenever needed in the course of gonadotropin-induced follicular development. 相似文献
38.
Josue Acevedo Allison L. Boden Dylan N. Greif Christopher P. Emerson Jeffrey T. Ruiz Jean Jose Luis A. Feigenbaum Lee D. Kaplan 《Journal of Athletic Training》2021,56(6):565
ContextManagement of isolated grade III medial collateral ligament injuries is controversial, as both nonoperative and operative management can result in return to play. However, operative management is recommended in elite athletes who have a grade III injury with distal avulsion.ObjectiveWe present a standardized rehabilitation protocol in a case series of 7 National Collegiate Athletic Association Division I American football athletes who sustained grade III distal medial collateral ligament tears that were repaired operatively, with emphasis on return to play.ResultsMedian time to surgery was 4 days (range = 2–67 days). Median time from surgery to noncontact drills was 120.5 days (range = 104–168 days), and median time from surgery to full-contact sport was 181 days (range = 139–204 days). All athletes returned to play at their preinjury level of competition.ConclusionsOur study highlighted how operative management with a standardized rehabilitation protocol can be applied to Division I football players and result in safe return to play. 相似文献
39.
Emerson Maniwang Nahid Tayebi Ellen Sidransky 《Molecular genetics and metabolism》2013,108(4):269-271
Several genetic risk factors have been identified for Parkinson disease (PD), including mutations in glucocerebrosidase (GBA1). Recently, two single nucleotide polymorphisms (SNPs) described as SCARB2 SNPs were reported to be associated with PD. SCARB2 is an attractive candidate gene for PD as it encodes for lysosomal integral membrane protein type 2 (LIMP-2), a protein involved in transporting glucocerebrosidase from the ER to the lysosome. The first SNP, rs6812193, located 64 kb upstream of SCARB2, was identified in a Parkinson disease Genome Wide Association study of Americans with European ancestry (p = 7.6 × 10? 10, OR = 0.84), but was not replicated in a study in the Han Chinese. The second SNP, rs6825004, located within intron 2 of SCARB2 was reported in an association study of Parkinson disease in Greece (p = 0.02, OR = 0.68). We explored whether the two SNPs impact SCARB2 expression or LIMP-2 protein levels, testing fifteen control samples. First, the genotypes for each subject were determined for both SNPs using a Taqman assay. Then, RNA and protein were extracted from the corresponding cell pellets. Neither the relative RNA expression by real-time PCR, nor LIMP-2 levels on Western blots correlated with SNP genotype. Thus, these two reported SNPs may not be related to SCARB2 and demonstrate the challenges in interpreting some association studies. While LIMP-2 could still play a role in PD pathogenesis, this study does not provide evidence that the SNPs identified are in fact related to LIMP-2. 相似文献
40.
Six weeks of aerobic training improves VO2max and MLSS but does not improve the time to fatigue at the MLSS 总被引:1,自引:0,他引:1
Thiago Teixeira Mendes Tatiana Ramos Fonseca Guilherme Passos Ramos Carolina Franco Wilke Christian Emmanuel Torres Cabido Cristiano Lino Monteiro De Barros André Maia Lima Lucas de Ávila Carvalho Fleury Mortimer Moisés Vieira de Carvalho Mauro Martins Teixeira Nilo Resende Viana Lima Emerson Silami Garcia 《European journal of applied physiology》2013,113(4):965-973
The purpose of this study was to investigate the effects of a 6-week aerobic training period on the time to fatigue (t lim) during exercise performed at the maximal lactate steady state (MLSS). Thirteen untrained male subjects (TG; age 22.5 ± 2.4 years, body mass 72.9 ± 6.7 kg and VO2max 44.9 ± 4.8 mL kg?1 min?1) performed a cycle ergometer test until fatigue at the MLSS power output before and after 6 weeks of aerobic training. A group of eight control subjects (CG; age 25.1 ± 2.4 years, body mass 70.1 ± 9.8 kg and VO2max 45.2 ± 4.1 mL kg?1 min?1) also performed the two tests but did not train during the 6-week period. There were no differences between the groups with respect to the VO2max or MLSS power output (MLSSw) before the treatment period. The VO2max and the MLSSw of the TG increased by 11.2 ± 7.2 % (pre-treatment = 44.9 ± 4.8 vs. post-treatment = 49.8 ± 4.5 mL kg?1 min?1) and 14.7 ± 8.9 % (pre-treatment = 150 ± 27 vs. post-treatment = 171 ± 26 W), respectively, after 6 weeks of training. The results of the CG were unchanged. There were no differences in t lim between the groups or within groups before and after training. Six weeks of aerobic training increases MLSSw and VO2max, but it does not alter the t lim at the MLSS. 相似文献