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981.
BACKGROUNDPatients with cirrhosis are at risk of cirrhotic cardiomyopathy, with resulting cardiac dysfunction and exercise limitations. Six minute walking test (6MWT) assesses functional status and predicts morbidity and mortality in cardiopulmonary diseases. AIMTo determine if it associates with mortality by analyzing 6MWT performance in patients with liver cirrhosis.METHODSA cohort of 106 cirrhotic patients was evaluated in the outpatient setting with echocardiogram and 6MWT and follow up for one year to document hepatic decompensation and mortality. The distance in meters was recorded at the end of 6 min (6MWD).RESULTSThis cohort had a mean age of 51 years and 56% male; patients were staged as Child A in 21.7%, B 66% and C 12.3%. Walk distance inversely correlated with Child scores, and was significantly reduced as Child stages progresses. Patients who died (10.4%) showed shorter mean 6MWD (P = 0.006). Low 6MWD was an independent predictor of mortality (P = 0.01).CONCLUSION6MWT is a noninvasive inexpensive test whose result is related to Child scores and mortality. It is useful to identify patients with liver cirrhosis at high risk of mortality for closer monitoring and potential early intervention.  相似文献   
982.
983.

Ethnopharmacological relevance

Baccharis trimera (Less.) (Asteraceae) is a native plant from Brazil. Also known as “carqueja”, it is popularly used to treat liver diseases, diabetes, as well as digestive disorders, mainly by women with lower socioeconomic status.

Aim of the study

The aim of the present study was to investigate the in vivo genotoxic/antigenotoxic and mutagenic potential of this plant, using the comet and the micronucleus assays.

Material and methods

Female adult mice were treated with 500, 1000 or 2000 mg/kg of B. trimera aqueous extract (Bt-AE) by gavage for three consecutive days.

Results

Independently of the dose, no genotoxic effect was observed in blood and liver samples analyzed by the comet assay. Conversely, B. trimera showed an antigenotoxic effect in blood from treated mice, thus protecting cells against oxidative DNA damage induced by the ex vivo treatment with hydrogen peroxide. In addition, Bt-AE showed in vitro antioxidant activity, assessed by DPPH and xanthine oxidase assays, suggesting that the observed antigenotoxic effects might be related to its antioxidant properties.

Conclusions

However, the extract increased the frequency of micronucleus in bone marrow of treated mice, indicating a chromosomal mutagenic activity. Thus, medicines prepared from this plant should be used with caution, although the results also suggest antigenotoxic effects for B. trimera aqueous extract.  相似文献   
984.

Background

The etiology of patellofemoral pain (PFP) is thought to be the result of increased patellofemoral joint (PFJ) load and aberrant lower extremity mechanics, including altered vertical ground reaction forces (VGRF). However, few studies have investigated the association between an increase in pain and VGRF loading rates in the context of PFP. Thus, this study aimed to investigate the immediate effects of PFJ loading on pain and VGRF loading rate, and to see if there is a link between modification of both pain and VGRF loading rate during stair negotiation.

Methods

Thirty-four women with PFP underwent VGRF analysis during stair negotiation under two conditions: with (condition 2) and without (condition 1) being previously submitted to a PFJ loading protocol in order to or not to exacerbate their knee pain, respectively.

Results

The VGRF loading rates were significantly higher in condition 2 (Mean ± standard deviation (SD) = 4.0 ± 0.6 N/s) compared to condition 1 (Mean ± SD = 3.6 ± 0.5 N/s) during stair ascent and during stair descent (Mean ± SD: condition 1 = 6.3 ± 1.1 N/s; condition 2 = 7.0 ± 1.4 N/s). In addition, VGRF loading rates were higher during stair descent compared to stair ascent in both conditions. There were significant correlations between the increase in pain and VGRF loading rate during both tasks.

Conclusion

There seemed to be an important relation between the increase in pain and VGRF loading rates in women with PFP. Based on these findings, interventions aimed at reducing VGRF loading rates are important in the context of PFP.  相似文献   
985.
The accumulation of chylous fluid in the abdominal cavity is an infrequent, yet alarming, complication in abdominal surgery. Laparoscopic fundoplication has assumed a central role in the surgical treatment of gastroesophageal reflux disease and is significantly altering the balance of therapy toward more common and earlier surgical intervention. We report the case of a 67-year-old woman with gastroesophageal reflux disease and intense esophagitis who underwent a laparoscopic Nissen fundoplication in February 2000. The procedure was performed without apparent complications. Twenty days later, the patient complained of abdominal pain and distension. Ultrasonography showed ascites, whereas endoscopic and radiological exploration of the fundoplication demonstrated no abnormalities. A paracentesis was performed, which showed a milky fluid with high concentrations of triglycerides (1024 ng/dL) and cholesterol (241 ng/dL). The patient was treated successfully with total parenteral nutrition for 3 weeks, followed by a low-fat diet. To our knowledge, this is the third reported case of chylous ascites after a Nissen fundoplication and the second case after laparoscopic fundoplication. The development of chylous ascites seems to be related to the injury of lymphatic vessels, including the thoracic duct, during the retroesophageal window dissection. The careful dissection and judicious use of diathermy is proposed to prevent this rare complication.  相似文献   
986.
PURPOSE: Total thyroidectomy (TT) with level VI and VII central neck dissection is the initial treatment for medullary thyroid carcinoma (MTC) without identifiable neck metastasis. Level II to V lateral neck dissection is performed if neck metastasis is present or suspected. We conducted this study to identify the frequency and clinical determinants of skip neck metastasis in MTC. METHODS: We reviewed the medical records of 32 patients who underwent TT and bilateral neck dissection for MTC. The clinical features were correlated with pN status in the central versus lateral compartments of the neck. RESULTS: Neck lymph node metastasis (pN+) was found in 20 patients (62.5%) and skip metastases were found in 7 (35%) patients. The sensitivity of the pN status of the central compartment of the neck to predict the pN status of the lateral compartment of the neck was 53.8% and specificity was 63.2%. We found pN+ in 90% of the patients with lymph nodes >15 mm in diameter versus 50% in those with lymph nodes <15 mm in diameter. CONCLUSIONS: There is skip metastasis in MTC. It is unsafe to use the lymph node status of the central compartment of the neck to define the pN status of the lateral neck. A lymph node greater than 15 mm in diameter is related to pN status.  相似文献   
987.
988.
In this study, a quinoline derivate, clioquinol (5‐chloro‐7‐iodoquinolin‐8‐ol), was evaluated against Leishmania amazonensis and Leishmania infantum promastigotes and amastigotes. The cytotoxicity in murine macrophages and human red blood cells, as well as the efficacy in treating infected macrophages and the inhibition of infection using pre‐treated parasites were also evaluated. Results showed that clioquinol inhibited L. amazonensis and L. infantum promastigotes with effective concentration 50% (EC50) values of 2.55 ± 0.25 and 1.44 ± 0.35 μg/mL, respectively, and of 1.88 ± 0.13 and 0.98 ± 0.17 μg/mL against axenic amastigotes, respectively. The cytotoxic EC50 concentrations of clioquinol in murine macrophages and human red blood cells were, respectively, 255 ± 23 and 489 ± 20 μg/mL. With these results, the selectivity index was calculated, showing values of 99.9 and 177.1 against promastigotes, respectively, and of 135.6 and 260.1 against axenic amastigotes, respectively. Significant reductions in the percentage of infected macrophages after treatment using clioquinol were also observed, as well as when parasites were pre‐treated with clioquinol and used to infect murine macrophages. The mechanism of action of clioquinol was investigated in L. amazonensis, and results revealed morphological and biochemical alterations in the clioquinol‐treated parasites, including reduction in cell volume, loss of mitochondrial membrane potential, increase in the ROS production and rupture of the plasma membrane. The externalization of phosphatidylserine (PS) at the cell surface was evaluated in treated parasites that had been doubly labelled with annexin and propidium iodide (PI). The results showed no significant difference for PS exposure when compared to the untreated control, although a significant increase in the PI/annexin V‐labelled cell population was found in the treated parasites. Results suggest that clioquinol induces a discontinuity of the parasite membrane, possibly related to a characteristic event of cell death caused by necrosis. This study demonstrates, for the first time, the antileishmanial activity of clioquinol against two relevant Leishmania species and suggests that the mitochondria of the parasites may be a possible biological target leading to parasite necrosis. Our findings suggest that clioquinol may have a potential application in treatment of leishmaniasis and further studies should be performed in infected mammalian hosts.  相似文献   
989.
990.
ABSTRACT

The sexual exploitation of children and adolescents is a frequently underestimated health problem which includes transactional sex (TS), or the practice of sexual activity based on an expected return of benefits, favours and/or support in some form. This qualitative study focuses on age-disparate transactional sex (ATS) in urban favela communities of Rio de Janeiro between adult men (over 18) and girls and adolescents (G/A) (under 18), involving a minimum 5-year age disparity. We have employed social norms theory as a framework to identify the prevailing social norms contributing to or protecting children and adolescents from these relationships. Data collection utilised semi-structured interviews (n?=?30) and ten focus groups with a total of 130 men/boys and women/girls selected through purposive sampling and varying in age from 15 to 65. Overall the findings identify factors, especially the essentialisation of gender, which promote the acceptability of ATS. When ATS surpassed the acceptability threshold, social norms discouraged direct interference. Concluding remarks point to possible strategies for reducing the occurrence of ATS. These must include girls, boys, women and men with community involvement in the deconstruction of social norms involving gender, age and economic consumption.  相似文献   
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