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91.
Tension development in response to direct and indirect electrical stimulation was studied in an isolated phrenic nerve hemidiaphragm preparation of the mouse. β-Endorphin (β-EP) caused an increase in the preparation of the mouse. β-Endorphin (β-EP) caused an increase in the response to low frequency stimulation of the nerve. Upon direct stimulation of the muscle the peptide had no effect. The actions of β-EP were abolished in the presence of the opioid antagonist naloxone and mimicked by β opioid agonists. Upon high frequency stimulation of the nerve, β-EP caused an increase in the initial, maximum, and mean tension. It also prevented the fall in the final tension seen in the control preparations with repeated periods of stimulation. The findings are consistent with β-EP having a role to improve neuromuscular function and deley fatigue, and indicate the possible therapeutic potential of opioid substances in conditions where muscle weakness is present. © John Wiley & Sons, Inc.  相似文献   
92.

Background

Patients with lower extremity peripheral artery disease (PAD) are at increased risk of major adverse cardiovascular events (MACE) and major adverse limb events (MALE). There is limited information on the prognosis of patients who experience MALE.

Objectives

Among participants with lower extremity PAD, this study investigated: 1) if hospitalizations, MACE, amputations, and deaths are higher after the first episode of MALE compared with patients with PAD who do not experience MALE; and 2) the impact of treatment with low-dose rivaroxaban and aspirin compared with aspirin alone on the incidence of MALE, peripheral vascular interventions, and all peripheral vascular outcomes over a median follow-up of 21 months.

Methods

We analyzed outcomes in 6,391 patients with lower extremity PAD who were enrolled in the COMPASS (Cardiovascular Outcomes for People Using Anticoagulation Strategies) trial. COMPASS was a randomized, double-blind placebo-controlled study of low-dose rivaroxaban and aspirin combination or rivaroxaban alone compared with aspirin alone. MALE was defined as severe limb ischemia leading to an intervention or major vascular amputation.

Results

A total of 128 patients experienced an incident of MALE. After MALE, the 1-year cumulative risk of a subsequent hospitalization was 61.5%; for vascular amputations, it was 20.5%; for death, it was 8.3%; and for MACE, it was 3.7%. The MALE index event significantly increased the risk of experiencing subsequent hospitalizations (hazard ratio [HR]: 7.21; p < 0.0001), subsequent amputations (HR: 197.5; p < 0.0001), and death (HR: 3.23; p < 0.001). Compared with aspirin alone, the combination of rivaroxaban 2.5 mg twice daily and aspirin lowered the incidence of MALE by 43% (p = 0.01), total vascular amputations by 58% (p = 0.01), peripheral vascular interventions by 24% (p = 0.03), and all peripheral vascular outcomes by 24% (p = 0.02).

Conclusions

Among individuals with lower extremity PAD, the development of MALE is associated with a poor prognosis, making prevention of this condition of utmost importance. The combination of rivaroxaban 2.5 mg twice daily and aspirin significantly lowered the incidence of MALE and the related complications, and this combination should be considered as an important therapy for patients with PAD. (Cardiovascular Outcomes for People Using Anticoagulation Strategies [COMPASS]; NCT01776424)  相似文献   
93.
Valuable effects of gold particles have been reported and used in complementary medicine for decades. The aim of this study was to evaluate the therapeutic efficacy of gold nanoparticles (AuNPs) against acetaminophen (APAP) induced toxicity. Albino rats were administered APAP at a dose of 2 g/kg p.o. once only. After 24 h of APAP intoxication, animals were treated with three different doses of AuNPs (50 μg/kg, 100 μg/kg, 150 μg/kg) orally or silymarin at a dose of 50 mg/kg p.o., once only. Animals of all the groups were sacrificed after 24 h of last treatment. APAP administered group showed a significant rise in the AST, ALT, SALP, LDH, cholesterol, bilirubin, albumin, urea and creatinine in serum which indicated the hepato-renal damage. A significantly enhanced LPO and a depleted level of GSH were observed in APAP intoxicated rats. Declined activities of SOD and Catalase, after acetaminophen exposure indicated oxidative stress in liver and kidney. The activities of ATPase and glucose-6-Phosphatase were significantly inhibited after APAP administration. AuNPs treatment reversed all variables significantly towards normal level and was found nontoxic. Thus it is concluded that gold nanoparticles played a beneficial role in reducing acetaminophen induced toxicity and can be used in the development of drug against hepatic as well as renal diseases, after further preclinical and clinical studies.  相似文献   
94.
Mutations or deletions involving ZFHX1B (previously SIP1) have recently been found to cause one form of syndromic Hirschsprung disease (HSCR), associated with microcephaly, mental retardation, and distinctive facial features. Patients with the characteristic facial phenotype and severe mental retardation, but without HSCR, have now also been shown to have mutations in this gene. Mutations of ZFHX1B are frequently associated with other congenital anomalies, including congenital heart disease, hypospadias, renal tract anomalies, and agenesis of the corpus callosum (ACC). We present the clinical data and mutation analysis results from a series of 23 patients with this clinical syndrome, of whom 21 have proven ZFHX1B mutations or deletions (15 previously unpublished). Two patients with the typical features (one with and one without HSCR) did not have detectable abnormalities of ZFHX1B. We emphasize that this syndrome can be recognized by the facial phenotype in the absence of either HSCR or other congenital anomalies, and needs to be considered in the differential diagnosis of dysmorphism with severe mental retardation +/- epilepsy.  相似文献   
95.

Aims

The pathogenesis, viral localization and histopathological features of Middle East respiratory syndrome – coronavirus (MERS‐CoV) in humans are not described sufficiently. The aims of this study were to explore and define the spectrum of histological and ultrastructural pathological changes affecting various organs in a patient with MERS‐CoV infection and represent a base of MERS‐CoV histopathology.

Methods and results

We analysed the post‐mortem histopathological findings and investigated localisation of viral particles in the pulmonary and extrapulmonary tissue by transmission electron microscopic examination in a 33‐year‐old male patient of T cell lymphoma, who acquired MERS‐CoV infection. Tissue needle biopsies were obtained from brain, heart, lung, liver, kidney and skeletal muscle. All samples were collected within 45 min from death to reduce tissue decomposition and artefact. Histopathological examination showed necrotising pneumonia, pulmonary diffuse alveolar damage, acute kidney injury, portal and lobular hepatitis and myositis with muscle atrophic changes. The brain and heart were histologically unremarkable. Ultrastructurally, viral particles were localised in the pneumocytes, pulmonary macrophages, renal proximal tubular epithelial cells and macrophages infiltrating the skeletal muscles.

Conclusion

The results highlight the pulmonary and extrapulmonary pathological changes of MERS‐CoV infection and provide the first evidence of the viral presence in human renal tissue, which suggests tissue trophism for MERS‐CoV in kidney.
  相似文献   
96.
Recurrent Crohn’s disease originates with small erosions in the follicle-associated epithelium overlying the Peyer’s patches. Animal studies have illustrated mucosal immune regulation by dendritic cells located in the subepithelial dome. The aim of this study was to characterize the dendritic cells at this specific site in patients with Crohn’s disease. Ileal tissues were obtained after surgery performed on Crohn’s patients; ileal samples from noninflammatory bowel disease and ulcerative colitis served as standard and inflammatory controls, respectively. Flow cytometry of isolated intestinal mononuclear cells showed a larger subset of dendritic cells in Crohn’s samples compared with controls. This finding was corroborated by confocal microscopy, showing enhanced infiltrates of cells positive for the dendritic cell markers, DC-SIGN+ and CD83+, in the subepithelial dome. Moreover, the CD83+ cells in Crohn’s tissues showed reduced expression of the lymph node migratory receptor, CCR7, possibly contributing to the high numbers of dendritic cells. After exposure to nonpathogenic Escherichia coli in Ussing chambers, dendritic cells in the subepithelial dome of Crohn’s disease demonstrated increased co-localization with translocated bacteria. Immunohistochemical results revealed that DC-SIGN+ cells in Crohn’s tissues were found to express toll-like receptor 4 and produce tumor necrosis factor-α. In conclusion, nonmigrating dendritic cells that accumulate in the subepithelial dome and internalize nonpathogenic bacteria may be important for the onset and perpetuation of mucosal inflammation in Crohn’s disease.  相似文献   
97.
Mechanical stimulation has been proposed to induce chondrogenesis in cell-seeded scaffolds. However, the effects of mechanical stimuli on engineered cartilage may vary substantially between different scaffolds. This advocates for the need to identify an overarching mechanobiological variable. We hypothesize that energy dissipation of scaffolds subjected to dynamic loading may be used as a mechanobiology variable. The energy dissipation would furnish a general criterion to adjust the mechanical stimulation favoring chondrogenesis in scaffold. Epiphyseal chondro-progenitor cells were then subject to unconfined compression 2 h per day during four days in different scaffolds, which differ only by the level of dissipation they generated while keeping the same loading conditions. Scaffolds with higher dissipation levels upregulated the mRNA of chondrogenic markers. In contrast lower dissipation of scaffolds was associated with downregulation of chondrogenic markers. These results showed that energy dissipation could be considered as a mechanobiology variable in cartilage. This study also indicated that scaffolds with energy dissipation level close to the one of cartilage favors chondrogenic expression when dynamical loading is present.  相似文献   
98.
Objective  To assess the zinc status in Bangladeshi children suffering from severe protein energy malnutrition (severe PEM), acute lower respiratory infection (ALRI), PEM presented with ALRI and to evaluate the relationship of zinc status with aforementioned clinical conditions. Methods  We assessed zinc status by simultaneous estimation of serum and hair zinc of Bangladeshi children less than 5 yr of age suffering from severe PEM, ALRI, severe PEM presented with ALRI and compared them with zinc status of well-nourished healthy children (control) in a hospital based cross sectional four cell study. Zinc concentration was estimated by Flame atomic absorption spectrophotometry. Results  Total one hundred and fifty two children were enrolled and number of children enrolled in severe PEM, ALRI, ALRI with PEM and control were 47, 35, 32 and 38 respectively. Both serum and hair zinc in univariate analysis were found significantly (p<0.05) low in severe PEM, ALRI and severe PEM associated with ALRI. However, in multivariate analysis, when serum and hair zinc were included in the same model, both serum and hair zinc were found to have significant negative association with PEM (p=0.002 & 0.013 respectively) and with ALRI only when ALRI was associated with PEM (p=0.043 and 0.034 respectively). Conclusion  Severe PEM and PEM with ALRI were significantly associated with low zinc status.  相似文献   
99.
100.
We report a newborn with a congenital aneurysm of the muscular interventricular septum, a conduction system abnormality involving variable left and right bundle branch block, and an abnormality of the short arm of chromosome 20, This combination of anomalies has not been previously reported. To date, the infant has progressed well from a cardiac perspective but has poor muscle tone and developmental delay.  相似文献   
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