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51.
Acute postinfectious glomerulonephritis are defined by an acute nonsuppurative inflammatory insult predominantly glomerular. Its current incidence is uncertain because of the frequency of subclinical forms. The most common infectious agent involved is beta hemolytic streptococcus group A. Acute postinfectious glomerulonephritis is uncommon in adults, and its incidence is progressively declining in developed countries. Humoral immunity plays a key role in the pathogenesis of kidney damage. Complement activation by the alternative pathway is the dominant mechanism, but a third way (lectin pathway) has been recently identified. The classic clinical presentation is sudden onset of acute nephritic syndrome after a free interval from a streptococcal infection. Treatment is essentially symptomatic and prevention is possible through improved hygiene and early treatment of infections.  相似文献   
52.
PURPOSE: To compare the pre and post treatment 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) imaging findings of an inflammatory myofibroblastic tumor (IMT) with its clinical response to immunosuppressive therapy. PROCEDURE: Forty-nine-year-old female presented with dyspnea, chest pain, and weight loss and underwent an FDG-PET/CT scan before and after mediastinal biopsy and treatment with dexamethasone and thalidomide. RESULTS: FDG-PET/CT scan demonstrated a hypermetabolic mediastinal mass. The biopsy of the lesion was consistent with IMT. Following immunosuppressive therapy, the patient's clinical findings resolved, and PET/CT showed a significant decrease in the FDG uptake and the size of the mass. CONCLUSION: Pre-treatment imaging features and post-treatment imaging characteristics of IMT correlate with clinical findings and suggest that FDG-PET/CT may be useful as an adjunct to clinical evaluation in monitoring of immunosuppressive therapy of IMT.  相似文献   
53.
This case report involves a 60-year-old diabetic man who developed septic arthritis as a result of the pathogen Morganella morganii. The patient had complaints of elevated body temperature, malaise, rigors and pain in the left knee, despite no history of trauma. On examination of the knee, erythema, warmth, tenderness and swelling was observed. Arthrocentesis performed on his left knee indicated the presence of straw-coloured, cloudy fluid without crystals. Bacterial identification based on biochemical and automated methods indicated the growth of M morganii. M morganii was also isolated sedimentafrom the exudate of a diabetic ulcer in the left foot, with antibiotic susceptibilities identical to those from the knee effusion. This case indicates that M morganii may be considered as a possible cause of septic arthritis in diabetic patients, especially those with diabetic foot infections.  相似文献   
54.
Near-Infrared Spectroscopy (NIRS) measures the functional hemodynamic response occurring at the surface of the cortex. Large pial veins are located above the surface of the cerebral cortex. Following activation, these veins exhibit oxygenation changes but their volume likely stays constant. The back-reflection geometry of the NIRS measurement renders the signal very sensitive to these superficial pial veins. As such, the measured NIRS signal contains contributions from both the cortical region as well as the pial vasculature. In this work, the cortical contribution to the NIRS signal was investigated using (1) Monte Carlo simulations over a realistic geometry constructed from anatomical and vascular MRI and (2) multimodal NIRS-BOLD recordings during motor stimulation. A good agreement was found between the simulations and the modeling analysis of in vivo measurements. Our results suggest that the cortical contribution to the deoxyhemoglobin signal change (ΔHbR) is equal to 16-22% of the cortical contribution to the total hemoglobin signal change (ΔHbT). Similarly, the cortical contribution of the oxyhemoglobin signal change (ΔHbO) is equal to 73-79% of the cortical contribution to the ΔHbT signal. These results suggest that ΔHbT is far less sensitive to pial vein contamination and therefore, it is likely that the ΔHbT signal provides better spatial specificity and should be used instead of ΔHbO or ΔHbR to map cerebral activity with NIRS. While different stimuli will result in different pial vein contributions, our finger tapping results do reveal the importance of considering the pial contribution.  相似文献   
55.

Background

To treat viral infection of chronic hepatitis C (CHC) is a main strategy to prevent progression of liver disease, and cancer. Some patients with CHC have failed to respond to the common antiviral therapy in different populations.

Objectives

In the current study it was aimed to find out the possible role of multiple drug resistance gene1 (MDR1) in non-responder patients with CHC infection in Turkish population.

Patients and Methods

Peripheral blood-EDTA samples were used for total genomic DNA isolation. In total of 55 patients with chronic hepatitis C and positive results for genotype 1 [31 male (56.4%), 24 female (43.6%) and mean age-min-max; 56.9 ± 9.66 (39-71)]; 19 responder (34.5%), 21 non responder (38.2%), and 15 recurrence (27.3%) were included in the presented results. Functional MDR1 gene was genotyped by multiplex PCR-based reverse-hybridization Strip Assay method, and some samples were confirmed by direct sequencing.

Results

Our results indicate that MDR1 gene polymorphism is strongly associated with non-responder patients and those with recurrent chronic hepatitis C during conventional drug therapy when compared to the responder patients. Homozygous of the TT genotype for MDR1 exon 26 polymorphism was at 2.0-fold higher risk of non-responder than patients with CC and CT.

Conclusions

The homozygous MDR1 3435TT genotype which encodes the xenobiotic transporter P-glycoprotein may be associated with a poor antiviral response in HCV chronicity during conventional therapy, and large-scale studies are needed to validate this association.  相似文献   
56.
Acidic vesicles are cytoplasmatic organelles delimited by a single lipoprotein membrane. They contain a large number of enzymes, mostly acidic hydrolases, catalysing various reactions at optimal acidic pH, capable of participating in intracellular digestion. In this paper, some anti-monoamine oxidase drugs (clorgyline, pargyline, amantadine and deprenyl), utilized as pharmacological treatment in some neurological disorders (e.g., Alzheimer’s, Parkinson’s etc. diseases), were tested for their ability to influence the pH of the acidic intracellular organelles with the aim of exploring their possible pharmacological action. Of the above mentioned drugs, clorgyline showed the most effective action in modifying the acidic vesicles’ internal pH, followed by deprenyl, pargyline and amantadine. The effect was not ascribed to an increased proton conductance, but was most likely due to a weak base-like mechanism, in that they exhibit equilibria among species associated with H+ ions and species lacking this association.  相似文献   
57.
BackgroundNon-dipper blood pressure is defined by less than a 10% reduction in nighttime blood pressure, and it is associated with cardiovascular disease. Inflammation is thought to play a role in the pathogenesis of both chronic obstructive pulmonary disease (COPD) and non-dipper blood pressure pattern, and both diseases are associated with lower quality of life.ObjectiveThe aim of this study was to investigate the effects of non-dipper blood pressure pattern in patients with COPD.MethodsA cross-sectional study was carried out with 142 patients with COPD. The Saint George Respiratory Questionnaire and the Euro Quality of Life Scale were used to collect data. To understand arterial stiffness, the augmentation index and pulse wave velocity were measured, and 24-hour ambulatory blood pressure monitoring was subsequently performed. A multivariable logistic regression model was used to understand the relationship between different independent variables and blood pressure pattern. P values lower than 0.05 were considered statistically significant.ResultsAs a result, 76.1% (n = 108) of the patients had non-dipper blood pressure pattern. Non-dipper patients had higher C-reactive protein (OR:1.123; 95% CI:1.016;1.242), augmentation index (OR: 1.057; 95% CI: 1.011;1.105) and Saint George Respiratory Questionnaire total score (OR: 1.021; 95% CI: 1.001;1.042) than dipper patients. Also, as the number of people living at home increased, non-dipper blood pressure pattern was found to be more frequent (OR: 1.339; 95% CI: 1.009;1.777).ConclusionNon-dipper blood pressure pattern may increase cardiovascular risk by triggering inflammation and may adversely affect the prognosis of COPD by lowering the disease-related quality of life. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)  相似文献   
58.
BACKGROUND: Actinic cheilitis is a common premalignant condition that is most often treated with destructive therapy. The most effective technique is usually considered to be CO2 laser resurfacing. Little has been written on the use of electrodessication for this condition. OBJECTIVE: We designed a study to compare these two treatment modalities for the treatment of biopsy-confirmed actinic cheilitis. METHODS: A random half of the lower lip was treated with electrodessication. The contralateral half was then treated with CO2 laser. Healing time, subjective pain during healing, and clinical outcome at 3 months was compared. RESULTS: The side treated with electrodessication took significantly longer to heal than the side treated with the CO2 laser (23 versus 14 days, P <.001). There was no difference in subjective pain or clinical appearance at 3 months. CONCLUSION: Although the healing time is longer with electrodessication, this modality represents an inexpensive practical ablative treatment method for actinic cheilitis.  相似文献   
59.
The lung is unique as leukocytes not only migrate into the bronchoalveolar space but also return to the parenchyma and then via the lymphatics to the draining lymph node. The aim of this study was to investigate the migration of leukocytes via an epithelial monolayer in a Transwell system against a chemokine gradient. Rat type I-like R3/1 alveolar epithelial cells were cultivated on a Transwell polyester membrane (pore diameter 3 microm) for 3 days until a monolayer was formed. The tightness of the monolayer was determined by transepithelial transport of horseradish peroxidase. Isolated human and rat peripheral blood mononuclear cells (PBMC) were placed in the upper chamber, and different concentrations of monocyte chemotactic protein-1 (MCP-1) in the lower chamber. The transmigration of PBMC was quantified and investigated by light and transmission electron microscopy. PBMC migrated through the epithelial cell barrier intercellularly as well as transcellularly. The migration of PBMC against the MCP-1 gradient was dose dependent. The results indicate that this model could help in the study of key events involved in chemokine-induced cell migration from the airways into tissue.  相似文献   
60.
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