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91.
Insertion of inferior vena cava filters has been well established in literature, reducing occurrence of pulmonary embolism after an episode of deep venous thrombosis in patients with contraindication to anticoagulation. There are a small number of complications related to procedure and embolization is rare. In this context, we described a case of intracardiac embolization associated with cardiac tamponade.  相似文献   
92.

Background

The upper esophageal sphincter is composed of striated muscle. The stress of intubation and the need to inhibit dry swallows during an esophageal manometry test may lead to variations in basal pressure of this sphincter. Upper esophageal sphincter is usually only studied at the final part of the test. Was observed during the performance of high resolution manometry that sphincter pressure may vary significantly over the course of the test.

Aim

To evaluate the variation of the resting pressure of the upper esophageal sphincter during high resolution manometry.

Methods

Was evaluated the variation of the basal pressure of the upper esophageal sphincter during high resolution manometry. Were reviewed the high resolution manometry tests of 36 healthy volunteers (mean age 31 years, 55% females). The basal pressure of the upper esophageal sphincter was measured at the beginning and at the end of a standard test.

Results

The mean time of the test was eight minutes. The basal pressure of the upper esophageal sphincter was 100 mmHg at the beginning of the test and 70 mmHg at the end (p<0.001). At the beginning, one patient had hypotonic upper esophageal sphincter and 14 hypertonic. At the end of the test, one patient had hypotonic upper esophageal sphincter (same patient as the beginning) and seven hypertonic upper esophageal sphincter.

Conclusion

A significant variation of the basal pressure of the upper esophageal sphincter was observed in the course of high resolution manometry. Probably, the value obtained at the end of the test may be more clinically relevant.  相似文献   
93.

Introduction

Renal transplantation (RT) in patients infected with human immunodeficiency virus (HIV) has significantly improved under the advent of combined antiretroviral therapy (cART). The authors describe their experience in RT in patients with HIV from September 2010 to June 2013.

Cases Report

Four patients underwent transplantation (3 with HIV-1 and 1 with HIV-2), three patients were male, and one was black. None were coinfected with hepatitis B virus (HBV) or hepatitis C virus (HCV). Etiology of kidney disease was HIV-associated nephropathy (2 patients), immunoglobulin (Ig)A nephropathy, and unknown. Average age at RT was 51 (range, 41–63) years. No patient was of high immunologic risk. Immunosuppression consisted of basiliximab for induction and prednisolone, tacrolimus (TAC), and mycophenolate mofetil for maintenance. TAC levels varied considerably in the early days (8.5–46 ng/mL), requiring major adjustments in TAC dose. Only the HIV-2 patient had delayed graft function. The follow-up of patients with HIV-1 was 37, 19, and 16 months, and 3 months for the HIV-2 patient. CD4+ T cells decreased in the early days after transplantation with subsequent improvement, along with persistent virological suppression. In the HIV-1 group there were no major infectious, cardiovascular, or neoplastic complications. Nevertheless, the HIV-2 patient died 3 months after RT due to H1N1 pneumonia complicated by pulmonary aspergillosis. Average estimated (CKD- EPI) glomerular filtration rate (eGFR) at 6 months was 85.6 mL/min/1.73 m2.

Conclusion

Besides the difficulty in adjusting calcineurin inhibitors levels due to its interaction with antiretroviral therapy, namely with protease inhibitors, no patient had acute rejection. Furthermore, all patients presented an excellent control of viro-immunologic parameters. At the last follow-up neither cardiovascular events nor neoplastic complications were observed. Our results highlight the favorable outcome of RT in HIV-1–infected patients. The HIV-2 patient died due to severe infection, and the clinical management and potential benefit of RT in HIV-2–infected patients needs further study.  相似文献   
94.
The aim of this study was to assess morphometrically and histologically, the effects of light-emitting diode (LED) (λ630?±?20 nm) phototherapy on reepithelialization and wound contraction during tissue repair in hypothyroid rats. Thyroid hormone deficiency has been associated with disorders of tissue repair. LED phototherapy has been studied using several healing models, but their usefulness in the improvement of hypothyroidism wound healing remains unknown. Under general anesthesia, a standard surgical wound (1 cm2) was produced on the dorsum of 48 male Wistar rats divided into four groups of 12 animals each: EC—control euthyroid, ED—euthyroid + LED, HC—control hypothyroid, and HD—Hypothyroid + LED. The irradiation started immediately after surgery and was repeated every other day for 7 and 14 days. Photographs of the wound were taken at the day of the surgical procedure and on days 8 and 15 after surgery, when animals’ deaths occurred. The specimens were removed, routinely processed, and stained with hematoxylin/eosin. Seven days after the surgery, it was possible to observe statistically significant reductions in the wound area of the irradiated euthyroid group, in comparison to hypothyroid group, irradiated and non-irradiated (ANOVA, p?<?0.05). The reepithelialization was significantly higher in the euthyroid and hypothyroid groups irradiated with LED than in the non-irradiated groups (Fisher’s test, p?<?0.05). No significant difference was found in the experimental period of 14 days among the groups. The hypothyroidism delayed wound healing and the LED phototherapy, at these specific parameters, improved the process of reepithelialization in the presence of hypothyroidism.  相似文献   
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98.
A reduced response of cystathionine beta-synthase (CBS) to its allosteric activator S-adenosylmethionine (SAM) has been reported to be a cause of CBS dysfunction in homocystinuria patients. In this work we performed a retrospective analysis of fibroblast data from 62 homocystinuria patients and found that 13 of them presented a disturbed SAM activation. Their genotypic background was identified and the corresponding CBS mutant proteins were produced in E. coli. Nine distinct mutations were detected in 22 independent alleles: the novel mutations p.K269del, p.P427L, p.S500L and p.L540Q; and the previously described mutations p.P49L, p.C165Rfs*2, p.I278T, p.R336H and p.D444N. Expression levels and residual enzyme activities, determined in the soluble fraction of E. coli lysates, strongly correlated with the localization of the affected amino acid residue. C-terminal mutations lead to activities in the range of the wild-type CBS and to oligomeric forms migrating faster than tetramers, suggesting an abnormal conformation that might be responsible for the lack of SAM activation. Mutations in the catalytic core were associated with low protein expression levels, decreased enzyme activities and a higher content of high molecular mass forms. Furthermore, the absence of SAM activation found in the patients’ fibroblasts was confirmed for all but one of the characterized recombinant proteins (p.P49L). Our study experimentally supports a deficient regulation of CBS by SAM as a frequently found mechanism in CBS deficiency, which should be considered not only as a valuable diagnostic tool but also as a potential target for the development of new therapeutic approaches in classical homocystinuria.  相似文献   
99.
The toxicity of titanium dioxide nanoparticles (TiO2‐NP) in the blood, liver, muscle, and brain of a Neotropical detritivorous fish, Prochilodus lineatus, was tested. Juvenile fish were exposed to 0, 1, 5, 10, and 50 mg L?1 of TiO2‐NP for 48 hours (acute exposure) or 14 days (subchronic exposure) to evaluate changes in hematology, red blood cell (RBC) genotoxicity/mutagenicity, liver function (reactive oxygen species (ROS) production, antioxidant responses, detoxification, and histopathology), acetylcholinesterase (AChE) activity in muscles and brain, and Ti bioaccumulation. TiO2‐NP did not cause genetic damage to RBC, but acutely decreased white blood cells (WBC) and increased monocytes. Subchronically, RBC decreased, mean cell volume and hemoglobin increased, and WBC and lymphocytes decreased. Therefore, NP has the potential to affect immune system and increase energy expenditure, reducing the fish's ability to avoid predator and to resist pathogens. In the liver, acute exposure decreased ROS and increased glutathione (GSH) content, while subchronic exposure decreased superoxide dismutase activity and increased glutathione‐S‐transferase (GST) activity and GSH content. GSH and GST seem to play an essential role in metabolizing NP and ROS, likely increasing hepatocytes' metabolic rate, which may be the cause of observed cell hypertrophy, disarrangement of hepatic cords and degenerative morphological alterations. Although most studies indicate that the kidney is responsible for metabolizing and/or eliminating TiO2‐NP, this study shows that the liver also has a main role in these processes. Nevertheless, Ti still accumulated in the liver, muscle, and brain and decreased muscular AChE activity after acute exposure, showing neurotoxic potential. More studies are needed to better understand the biochemical pathways TiO2‐NP are metabolized and how its bioaccumulation may affect fish homeostasis and survival in the environment.  相似文献   
100.
Some evidences suggest the involvement of the central nervous system in patients infected with SARS-CoV-2. We aim to analyze possible associations between coronavirus disease 2019 (COVID-19) pandemic and spontaneous subarachnoid hemorrhage (SAH), in a comprehensive neurological center.We conducted a retrospective case series of 4 patients infected by COVID-19, who developed spontaneous SAH. Clinical data were extracted from electronic medical records.Between March 24, 2020, and May 22, 2020, 4 cases (3 females; 1 male) of SAH were identified in patients infected with SARS-CoV-2, in a comprehensive neurological center in Brazil. The median age was 55.25 years (range 36 -71). COVID-19-related pneumonia was severe in 3 out of 4 cases, and all patients required critical care support during hospitalization. The patients developed Fisher grade III and IV SAH. Digital subtraction angiography (DSA) was performed in 3 of the 4 patients. However, in only 1 case, an aneurysm was identified. Inflammatory blood tests were elevated in all cases, with an average D-dimer of 2336 μg/L and mean C-reactive protein (CRP) of 3835 mg/dl The outcome was poor in the majority of the patients, with 1 death (25%); 2 (50%) remained severely neurologically affected (mRS:4); and 1 (25%) had slight disability (mRS:2).This study shows a series of 4 rare cases of SHA associated with COVID-19. The possible mechanisms underlying the involvement of SARSCoV-2 and SHA is yet to be fully understood. Therefore, SHA should be included in severe neurological manifestations in patients infected by this virus.  相似文献   
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