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611.
Systemic Sclerosis is a connective tissue disorder featuring vascular alterations and an immunological activation leading to a progressive and widespread fibrosis of several organs such as the skin, lung, gastrointestinal tract, heart and kidney. Moreover men with systemic sclerosis (SSc) present an increased risk of developing erectile dysfunction (ED). Recently, we evaluated the extent of penile vascular damage in sclerodermic patients using Duplex ultrasonography. The aim of this paper is to investigate whether penile thermal differences exist between sclerodermic patients and healthy controls. For this reason 10 men with SSc receiving current treatment for their disease, and 10 healthy controls were enrolled; penile thermal properties were assessed through non-contact thermal imaging (functional Infra Red Imaging fIRI); erectile function was evaluated using the sexual health inventory for men (SHIM) questionnaire. The SHIM results confirmed the presence of ED in sclerodermic patients. Baseline penile temperature in patients (32.1 +/- 1.4 degrees C) was lower than in controls (34.1 +/- 0.9 degrees C). Recovery from cooling test was seen to be faster in healthy controls than in patients, both in terms of recovery amplitude (patients 3.75 +/- 2.09 degrees C, controls 9.80 +/- 2.77 degrees C) and amplitude to time constant ratio (patients 1.21 +/- 0.64 degrees C/min, controls 1.96 +/- 0.48 degrees C/min). These results show that penile thermal abnormalities occur in almost all sclerodermic patients. Non-contact thermal imaging not only identifies thermal alterations but also clearly distinguishes between SSc patients and healthy controls and therefore could represent a valuable instrument in identifying early ED in SSc patients.  相似文献   
612.
CONTEXT: Papillary thyroid carcinoma (PTC) is frequently multifocal. Independent PTC foci may occur either from intraglandular metastases from a single dominant tumor or as unrelated neoplastic clones. In rare cases, the simultaneous presence of PTC foci of different histopathological subtypes points to independent sites of tumor formation. OBJECTIVES: We examined the pattern of BRAF mutations in noncontiguous tumor foci and node metastases from 69 patients affected by multicentric PTC. These included 19 cases characterized by the simultaneous presence of different PTC histopathological variants. DESIGN: BRAF (exon 15) mutation was examined by PCR-single strand conformational polymorphism followed by DNA sequencing in laser-capture microdissected tissue samples. RESULTS: Discordant patterns of BRAF mutation were found in about 40% of the multifocal PTCs. In node metastases, BRAF mutations were, in most but not all the cases, concordant with the dominant tumor. A discordant pattern of BRAF mutation was also found in about 50% of the cases in which multiple foci of different histopathological variants were present. CONCLUSIONS: The heterogeneous distribution of BRAF mutations suggests that discrete tumor foci in multifocal PTC may occur as independent tumors. This information has to be considered in the design of targeted therapeutic approaches with BRAF pathway inhibitors.  相似文献   
613.
Researchers in the health field often deal with the problem of incomplete databases. Complete Case Analysis (CCA), which restricts the analysis to subjects with complete data, reduces the sample size and may result in biased estimates. Based on statistical grounds, Multiple Imputation (MI) uses all collected data and is recommended as an alternative to CCA. Data from the study Saúde em Beagá, attended by 4,048 adults from two of nine health districts in the city of Belo Horizonte, Minas Gerais State, Brazil, in 2008-2009, were used to evaluate CCA and different MI approaches in the context of logistic models with incomplete covariate data. Peculiarities in some variables in this study allowed analyzing a situation in which the missing covariate data are recovered and thus the results before and after recovery are compared. Based on the analysis, even the more simplistic MI approach performed better than CCA, since it was closer to the post-recovery results.  相似文献   
614.
BACKGROUND AND OBJECTIVES: The aim of this prospective, observational study was to evaluate changes in regional cerebral oxygen saturation (rSO2) and incidence of intraoperative cerebral desaturation in a cohort of elderly patients undergoing major abdominal surgery. METHODS: rSO2 was continuously monitored on the left and right sides of the forehead in 60 patients older than 65 yr (35 males and 25 females; ASA II-III; age: 72 +/- 5 yr; without pre-existing cerebral pathology, and baseline Mini Mental State Examination (MMSE) score >23) undergoing sevoflurane anaesthesia for major abdominal, non-vascular surgery >2 h. RESULTS: Baseline rSO2 was 63 +/- 8%; cerebral desaturation (rSO2 decrease <75% of baseline or <80% in case of baseline rSO2 <50%) occurred in 16 patients (26%). The MMSE decreased from 28 +/- 1 before surgery to 27 +/- 2 on 7th postoperative day (P = 0.05). A decline in cognitive function (decrease in MMSE score > or = 2 points one week after surgery as compared to baseline value) was observed in six patients without intraoperative cerebral desaturation (13.6%) and six patients who had intraoperative cerebral desaturation (40%) (P = 0.057) (odds ratio: 4.22; CI95%: 1.1-16). Median (range) hospital stay was 14 (5-41) days in patients with an area under the curve of rSO2 <50% (AUCrSO2<50%) >10 min%, and 10 (4-30) days in those with an AUCrSO2<50% <10 min% (P = 0.0005). CONCLUSIONS: In a population of healthy elderly patients, undergoing non-vascular abdominal surgery cerebral desaturation can occur in up to one in every four patients, and the occurrence of cerebral desaturation is associated with a higher incidence of early postoperative cognitive decline and longer hospital stay.  相似文献   
615.
Unusual presentation of leptospirosis in the late stage of pregnancy   总被引:1,自引:0,他引:1  
Here we report a case of leptospirosis without fever during the late stage of pregnancy in which the initial clinical presentation was more suggestive of a pregnancy-related liver dysfunction rather than an infectious disease. A 32-year-old primipara at 37 week of gestation was hospitalised with a 10-day history of nausea, vomiting, and abdominal pain without fever. Initial routine blood tests showed hyperbilirubinemia, a moderate increase in transaminase levels, severe coagulopathy and an increased creatinine level. On clinical suspicion of pregnancy-related liver dysfunction such as HELLP syndrome (hemolysis, elevated liver enzyme levels, low platelet count) or acute fatty liver of pregnancy (AFLP), emergency caesarean section was performed and a healthy baby was delivered. Postoperatively, the patient was stable, but 5 days later she developed clouding of consciousness, severe jaundice and respiratory failure. At this time, an infectious disease was considered and leptospirosis was confirmed by serological tests. In conjunction with intensive care management, antibiotic therapy was given; the patient was discharged in good condition and her baby did not develop signs of active leptospirosis. While leptospirosis is rare in pregnancy, this is the first report of acute infection without fever mimicking the clinical pattern of HELLP syndrome or AFLP  相似文献   
616.
OBJECTIVE: To verify the adequacy of hospital resources for perinatal care in Belo Horizonte, MG, Brazil in 1996. METHODS: This is a cross-sectional study conducted encompassing all the 28 maternity-hospitals in the city of Belo Horizonte, capital of the State of Minas Gerais, Brazil. A model of evaluation denominated "Níveis de Complexidade e Seguran?a em Potencial de Unidades Perinatais de Hospitais-Maternidade" [Levels of Complexity and Potential Safety in Maternity-Hospitals]. This model is based on the evaluation of three major areas in the hospital: general structure, perinatal clinical infra-structure and resources available in perinatal units. Two scores involving these three areas were created. When evaluating low risk perinatal care, the score may sum to a total of 1,000 points. On the other hand, when high to medium perinatal risk care is considered, the score may sum to 2,000 points. Hosptals that scored more than 500 points were classified in two levels: I-A and I-B (for low risk); and six levels I-A through III-B (for medium/high risk). RESULTS: Five hospitals were classified as level 0 according to the low risk score, that is, they were not considered adequate to assist any delivery. When the medium/high risk score was employed, a total of seven hospitals were considered inadequate to assist any delivery. CONCLUSIONS: This evaluation model was capable of classifying hospitals according to available infra-structure for perinatal care.  相似文献   
617.
618.
Protein phosphatase 2B (PP2B) is critical for synaptic plasticity and learning, but the molecular mechanisms involved remain unclear. Here we identified different types of proteins that interact with PP2B, including various structural proteins of the postsynaptic densities (PSDs) of Purkinje cells (PCs) in mice. Deleting PP2B reduced expression of PSD proteins and the relative thickness of PSD at the parallel fiber to PC synapses, whereas reexpression of inactive PP2B partly restored the impaired distribution of nanoclusters of PSD proteins, together indicating a structural role of PP2B. In contrast, lateral mobility of surface glutamate receptors solely depended on PP2B phosphatase activity. Finally, the level of motor learning covaried with both the enzymatic and nonenzymatic functions of PP2B. Thus, PP2B controls synaptic function and learning both through its action as a phosphatase and as a structural protein that facilitates synapse integrity.SIGNIFICANCE STATEMENT Phosphatases are generally considered to serve their critical role in learning and memory through their enzymatic operations. Here, we show that protein phosphatase 2B (PP2B) interacts with structural proteins at the synapses of cerebellar Purkinje cells. Differentially manipulating the enzymatic and structural domains of PP2B leads to different phenotypes in cerebellar learning. We propose that PP2B is crucial for cerebellar learning via two complementary actions, an enzymatic and a structural operation.  相似文献   
619.
620.
A number of patients attending specialty headache centers complain of very frequent, almost continuous headaches, which are usually grouped together under the term chronic daily headache (CDH), a category which does not appear in the International Headache Society (IHS) classification published in 1988. More than 10 years later, this issue is still debated, also in light of the foreseen revised classification. Several terms have been used to define the clinical picture of CDH, and different criteria have been proposed for the diagnosis of these forms. In most cases, CDH appears to evolve from an episodic migraine, but the temporal limits between an episodic and a no-longer episodic form of migraine are questionable. Although some theoretic problems remain unresolved, it seems that the next revision of the IHS classification can no longer ignore the existence of CDH.  相似文献   
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