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991.
Skin lesions in sarcoidosis are often the initial symptoms that enable the dermatologist to be the first to diagnose this granulomatosis. However, diagnosis is sometimes very problematic. In 2015, the diagnostic criteria for sarcoidosis were updated in Japan, with elevated serum soluble interleukin‐2 receptor (sIL‐2R) replacing negative tuberculin reaction. Therefore, we assessed the clinical utility of sIL‐2R compared with two other common markers, angiotensin‐converting enzyme (ACE) and lysozyme, in patients who visited the dermatology clinic. Data from 72 patients showed that sIL‐2R was more sensitive than both ACE and lysozyme in supporting a diagnosis of sarcoidosis (52.8%) compared with ACE (29%) and lysozyme (26.4%). Additionally, the sIL‐2R level was significantly higher in patients with multiple organ involvement and parenchymal infiltration. Patients with elevated sIL‐2R levels had higher serum ACE and lysozyme levels, a higher incidence of pulmonary involvement, more severe chest radiographic stage and a high incidence of expression‐specific signs by imaging analysis. Receiver–operator curve analysis showed that sIL‐2R was a better marker at the threshold cut‐off point compared with ACE and lysozyme for identifying patients with multiple organ involvement, detecting patients with pulmonary disease and parenchymal infiltration as well as predicting the presence of specific signs in the diagnosis of sarcoidosis. Moreover, the kinetics of sIL‐2R levels correlated closely with clinical manifestations, in contrast to the modest changes of ACE and lysozyme levels during the follow‐up period. In conclusion, sIL‐2R may be considered a good marker for diagnosis and a potential indicator of disease activity.  相似文献   
992.
Chronic cellular stress associated with neurodegenerative disease can result in the persistence of stress granule (SG) structures, membraneless organelles that form in response to cellular stress. In Huntington’s disease (HD), chronic expression of mutant huntingtin generates various forms of cellular stress, including activation of the unfolded protein response and oxidative stress. However, it has yet to be determined whether SGs are a feature of HD neuropathology. We examined the miRNA composition of extracellular vesicles (EVs) present in the cerebrospinal fluid (CSF) of patients with HD and show that a subset of their target mRNAs were differentially expressed in the prefrontal cortex. Of these targets, SG components were enriched, including the SG-nucleating Ras GTPase-activating protein-binding protein 1 (G3BP1). We investigated localization and levels of G3BP1 and found a significant increase in the density of G3BP1-positive granules in the cortex and hippocampus of R6/2 transgenic mice and in the superior frontal cortex of the brains of patients with HD. Intriguingly, we also observed that the SG-associated TAR DNA-binding protein 43 (TDP43), a nuclear RNA/DNA binding protein, was mislocalized to the cytoplasm of G3BP1 granule–positive HD cortical neurons. These findings suggest that G3BP1 SG dynamics may play a role in the pathophysiology of HD.  相似文献   
993.
目的 研究机械刺激对大鼠骨髓间充质干细胞(bone marrow mesehchymal stem cells,BMSCs)分化的影响.方法 对大鼠BMSCs施以10%形变,1 Hz的周期性单向牵张刺激,并检测牵张不同时段后,其Ⅰ型、Ⅲ型胶原mRNA的表达和这2种蛋白的分泌.结果 牵张12 h后,BMSCs Ⅰ型胶原和Ⅲ型胶原mRNA的表达与对照组相比增高有显著差异,24 h后,种胶原蛋白的合成与对照组相比有统计学差别.结论 说明机械刺激可以促进BMSCs合成Ⅰ型胶原和Ⅲ型胶原蛋白.  相似文献   
994.
The cardiac aging process is accompanied by global mechanical dysfunction that reflects increased myocardial stiffness. Accordingly, age-related changes in microscopic material properties of myocardium were delineated with high-frequency ultrasound (US) (30 to 44 MHz) tissue characterization methods for aging Fischer 344 rats at 6 (adult), 18 (aged), and 24 (senescent) months of age. The excised lateral wall of the left ventricle of rats (n = 10 per group) was insonified with a 50-MHz acoustic microscope for determination of integrated backscatter, backscatter coefficient and attenuation coefficient. Histological and biochemical analyses for collagen content and cardiac myocyte diameter were performed. Collagen concentration increased progressively with age, with the greatest increments occurring from 6 to 18 months (38.0 +/- 6.3 to 53.0 +/- 7.1 mg/g dry wt), and leveling off at 24 months (60.0 +/- 7.4 mg/g dry wt). Tissue microscopic material properties also changed progressively from 6 to 24 months of age, as determined by US methods: integrated backscatter increased (-44.7 +/- 1.8 vs. -40.8 +/- 1.9 dB, p < 0.05), attenuation increased (47.1 +/- 5.9 to 65.3 +/- 7.8 dB/cm, p < 0.05), and the backscatter coefficient increased (0.73 +/- 0.16 x 10(-5) to 3.76 +/- 1.6 x 10(-5) cm(-1), p < 0.05), from 6 to 24 months of age in each case. Age-related alterations in indices of cardiac microscopic material properties were closely correlated with the changes in cardiac microstructure. Ultrasonic tissue characterization may prove to be a sensitive tool to monitor changes in the cardiac microstructure, such as increased collagen deposition, that occur within age-related diastolic dysfunction.  相似文献   
995.
996.
Despite good clinical results, the mechanisms of action of spinal cord stimulation (SCS) for the treatment of chronic refractory neuropathic pain have not yet been elucidated. In the present study, the effects of SCS were assessed on various neurophysiological parameters in a series of 20 patients, successfully treated by SCS for mostly unilateral, drug-resistant lower limb pain due to failed back surgery syndrome. Plantar sympathetic skin response (SSR), F-wave and somatosensory-evoked potentials (P40-SEP) to tibial nerve stimulation, H-reflex of soleus muscle, and nociceptive flexion (RIII) reflex to sural nerve stimulation were recorded at the painful lower limb. The study included two recording sets while SCS was switched ‘ON’ or ‘OFF’ for 1 h. Significant changes in ‘ON’ condition were as follows: SSR amplitude, H-reflex threshold, and RIII-reflex threshold and latency were increased, whereas SSR latency, F-wave latency, H-reflex amplitude, P40-SEP amplitude, and RIII-reflex area were reduced. Analgesia induced by SCS mainly correlated with RIII attenuation, supporting a real analgesic efficacy of the procedure. This study showed that SCS is able to inhibit both nociceptive (RIII-reflex) and non-nociceptive (P40-SEP, H-reflex) myelinated sensory afferents at segmental spinal or supraspinal level, and to increase cholinergic sympathetic skin activities (SSR facilitation). Complex modulating effects can be produced by SCS on various neural circuits, including a broad inhibition of both noxious and innocuous sensory information processing.  相似文献   
997.
OBJECTIVE: Our objective was to determine the typical distribution of thrombi in acute lower extremity deep venous thrombosis as a means of evaluating the validity of imaging techniques that only include the common femoral and popliteal veins, but not the superficial femoral vein. MATERIALS AND METHODS: The results of 2704 lower extremity venous sonograms, obtained in 2026 consecutive patients over a 4-year interval, were reviewed retrospectively. The distribution of acute deep venous thromboses across various lower extremity venous segments was analyzed for this population, which consisted of both symptomatic and asymptomatic patients. RESULTS: Of 2704 lower extremities studied with duplex sonography, acute deep venous thrombosis was identified in 269 (9.9%). Of these 269 cases, acute deep venous thrombosis was isolated to the superficial femoral vein in 60 (22.3%). The remaining 209 cases (77.7%) showed thrombus that extended into the common femoral or popliteal veins (or both). CONClUSION: An abbreviated imaging study that evaluates only the common femoral and popliteal veins would fail to identify more than 20% of lower extremity acute deep venous thromboses in a population like ours. Although evaluation of the superficial femoral vein requires additional time and resources, evaluation of this segment may prevent a substantial number of thrombi from being missed.  相似文献   
998.
999.
OBJECTIVE: To establish the relationship between the first-trimester screening markers [pregnancy-associated plasma protein A (PAPP-A), free human chorionic gonadotrophin-beta (beta-hCG), nuchal translucency (NT)], the Down syndrome (DS) risk estimate, and the adverse outcomes such as low birth weight, small for gestational age (SGA) and pre-term delivery. METHODS: A retrospective cohort study including 1,734 non-selected singleton pregnancies consecutively enrolled into the programme of first-trimester combined screening for DS in a 12-month period at a single centre. Data from the Prenatal Patient Registry in ASTRAIA were combined with the Danish National Newborn Screening Registry and Danish Birth Registry. RESULTS: There was a significant relation between low PAPP-A MoM, low beta-hCG MoM, increased risk estimate for DS and low birth weight and SGA. Low PAPP-A MoM and increased NT showed a significant relation to pre-term and spontaneous pre-term delivery. Low PAPP-A MoM showed a significant relation to early pre-term delivery. CONCLUSION: First-trimester screening markers exhibited a significant relation to low birth weight, SGA and to some extent, to pre-term and early pre-term delivery. The screening performance of individual markers was poor.  相似文献   
1000.
The wide use of continuous of fetal heart rate monitoring (FHR) since the seventies has been accompanied by an increase in cesarean delivery rates, without any decrease in cerebral palsy rate. Second line methods of fetal monitoring have been developed in order to better identify fetuses truly at risk of intrapartum asphyxia. The use of fetal scalp blood sampling (FBS) for fetal monitoring seems logical since neonatal acidosis is one of the major criteria of birth asphyxia. Studies show that the use of FBS reduces the increase in cesarean deliveries associated with the use of continuous FHR monitoring. However, FBS is invasive, non continuous and technically uneasy, with a rather high rate of failed blood samplings. Fetal scalp lactates measurement by micromethod requires a much smaller volume of blood. Although a wider assessment is required, the predictive value of fetal blood lactates seems to be similar to that of fetal scalp blood pH.  相似文献   
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