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81.
Cancer cachexia (CC), a progressive loss of body mass, is associated with decreased energy production. Abnormally low levels of L-carnitine (LC) in skeletal muscle means that mitochondrial β-oxidation of long-chain fatty acids (LCFA) does not occur efficiently in patients with CC. We assessed the influence of CC on LC distribution and the effects of parenteral lipid emulsions on plasma LC levels and urinary excretion. Fifty patients with CC were randomly assigned to total parenteral nutrition (TPN) with long-chain triglycerides (LCTs), or LCTs plus medium-chain triglycerides (MCTs) as 50/50. Patients were further separated into those with body-mass index (BMI) ≤ 19 kg/m(2) and BMI >19 kg/m(2). Plasma concentrations of total LC (TC) and free LC (FC) and their urinary excretion were measured, along with skeletal muscle LC levels. On average, plasma FC and TC were higher than reference values in all patients. Patients with BMI ≤ 19 kg/m(2) had lower plasma FC and TC than those with BMI >19 kg/m(2). Skeletal muscle FC in the BMI ≤ 19 kg/m(2) group was lower than reference value, but within the normal range in others. LC and FC urinary excretion was higher than reference values. Plasma LC and its urinary excretion were higher in patients administered pure LCTs relative to those given MCTs/LCTs. A decrease in skeletal muscle LC in cancer patients with CC (BMI ≤ 19 kg/m(2)) correlates with an increase in its plasma levels and increased renal excretion. A diet of MCTs/LCTs reduces LC release from muscle to plasma and urine more effectively than LCTs.  相似文献   
82.
Reduced expression of the metastasis suppressor NM23-H1 is associated with aggressive forms of multiple cancers. Here, we establish that NM23-H1 (termed H1 isoform in human, M1 in mouse) and two of its attendant enzymatic activities, the 3'-5' exonuclease and nucleoside diphosphate kinase, are novel participants in the cellular response to UV radiation (UVR)-induced DNA damage. NM23-H1 deficiency compromised the kinetics of repair for total DNA polymerase-blocking lesions and nucleotide excision repair of (6-4) photoproducts in vitro. Kinase activity of NM23-H1 was critical for rapid repair of both polychromatic UVB/UVA-induced (290-400 nm) and UVC-induced (254 nm) DNA damage, whereas its 3'-5' exonuclease activity was dominant in the suppression of UVR-induced mutagenesis. Consistent with its role in DNA repair, NM23-H1 rapidly translocated to sites of UVR-induced (6-4) photoproduct DNA damage in the nucleus. In addition, transgenic mice hemizygous-null for nm23-m1 and nm23-m2 exhibited UVR-induced melanoma and follicular infundibular cyst formation, and tumor-associated melanocytes displayed invasion into adjacent dermis, consistent with loss of invasion-suppressing activity of NM23 in vivo. Taken together, our data show a critical role for NM23 isoforms in limiting mutagenesis and suppressing UVR-induced melanomagenesis.  相似文献   
83.
The present study examines the association between disgust sensitivity (DS) and obsessive-compulsive disorder (OCD) symptoms in two non-clinical samples. Findings from Study 1 (n = 270) revealed a significant association between DS and OCD symptoms even after controlling for negative affect and anxiety sensitivity. Subsequent analysis also revealed a specific association between DS and the washing subtype of OCD symptoms when controlling for other OCD symptom dimensions. DS did not significantly predict residual change in total symptoms of OCD over a 12-week period (n = 300) when controlling for risk factors for anxiety disorder symptoms in general (e.g., negative affect, anxiety sensitivity) and OCD specifically (e.g., obsessive beliefs) in Study 2. However, exploratory analyses suggest that DS may be predictive of residual change in some OCD symptom subtypes but not others. Implications of these findings for future research on the role of disgust in OCD are discussed.  相似文献   
84.
Compared with our understanding of endochondral ossification, much less is known about the coordinated arrest of growth defined by the narrowing and fusion of the cartilaginous growth plate. Throughout the musculoskeletal system, appropriate cell and tissue responses to mechanical force delineate morphogenesis and ensure lifelong health. It remains unclear how mechanical cues are integrated into many biological programs, including those coordinating the ossification of the adolescent growth plate at the cessation of growth. Primary cilia are microtubule-based organelles tuning a range of cell activities, including signaling cascades activated or modulated by extracellular biophysical cues. Cilia have been proposed to directly facilitate cell mechanotransduction. To explore the influence of primary cilia in the mouse adolescent limb, we conditionally targeted the ciliary gene Intraflagellar transport protein 88 (Ift88fl/fl) in the juvenile and adolescent skeleton using a cartilage-specific, inducible Cre (AggrecanCreERT2 Ift88fl/fl). Deletion of IFT88 in cartilage, which reduced ciliation in the growth plate, disrupted chondrocyte differentiation, cartilage resorption, and mineralization. These effects were largely restricted to peripheral tibial regions beneath the load-bearing compartments of the knee. These regions were typified by an enlarged population of hypertrophic chondrocytes. Although normal patterns of hedgehog signaling were maintained, targeting IFT88 inhibited hypertrophic chondrocyte VEGF expression and downstream vascular recruitment, osteoclastic activity, and the replacement of cartilage with bone. In control mice, increases to physiological loading also impair ossification in the peripheral growth plate, mimicking the effects of IFT88 deletion. Limb immobilization inhibited changes to VEGF expression and epiphyseal morphology in Ift88cKO mice, indicating the effects of depletion of IFT88 in the adolescent growth plate are mechano-dependent. We propose that during this pivotal phase in adolescent skeletal maturation, ciliary IFT88 protects uniform, coordinated ossification of the growth plate from an otherwise disruptive heterogeneity of physiological mechanical forces. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
85.
86.

Objective

To investigate the hypoglycemic, hypolipidemic and antioxidant activities of aqueous extract of Terminalia paniculata bark (AETPB) in streptozotocin (STZ)-induced diabetic rats.

Methods

Acute toxicity was studied in rats after the oral administration of AETPB to determine the dose to assess hypoglycemic activity. In rats, diabetes was induced by injection of STZ (60 mg/kg, i.p.) and diabetes was confirmed 72 h after induction, and then allowed for 14 days to stabilize blood glucose level. In diabetic rats, AETPB was orally given for 28 days and its effect on blood glucose and body weight was determined on a weekly basis. At the end of the experimental day, fasting blood sample was collected to estimate the haemoglobin (Hb), glycosylated haemoglobin (HbA1c), serum creatinine, urea, serum glutamate-pyruvate transaminase (SGPT), serum glutamate-oxaloacetate transaminase (SGOT) and insulin levels. The liver and kidney were collected to determine antioxidants levels in diabetic rats.

Results

Oral administration of AETPB did not exhibit toxicity and death at a dose of 2 000 mg/kg. AETPB treated diabetic rats significantly (P<0.001, P<0.01 and P<0.05) reduced elevated blood glucose, HbA1c, creatinine, urea, SGPT and SGOT levels when compared with diabetic control rats. The body weight, Hb, insulin and total protein levels were significantly (P<0.001, P<0.01 and P<0.05) increased in diabetic rats treated with AETPB compared to diabetic control rats. In diabetic rats, AETPB treatment significantly reversed abnormal status of antioxidants and lipid profile levels towards near normal levels compared to diabetic control rats.

Conclusions

Present study results confirm that AETPB possesses significant hypoglycemic, hypolipidemic and antioxidant activities in diabetic condition.  相似文献   
87.
Neurotoxic intrathecal chemotherapy for childhood acute lymphoblastic leukemia (ALL) affects developing structures and functions of memory and learning subsystems selectively. Results show significant reductions in magnetic resonance imaging morphometry of mamillary bodies, components of the corticolimbic-diencephalic subsystem subserving functionally later developing, single-trial memory, nonsignificant changes in bilateral heads of the caudate nuclei, components of the corticostriatal subsystem subserving functionally earlier developing, multitrial learning, significant reductions in prefrontal cortical volume, visual and verbal single-trial memory deficits, and visuospatial, but not verbal, multitrial learning deficits. Multiple regression models provide evidence for partial dissociation and connectivity between the subsystems, and suggest that greater involvement of caudate may compensate for inefficient corticolimbic-diencephalic components.  相似文献   
88.
89.
1病例报告患者,男,22岁,因间歇性全身乏力、肌肉酸痛2 wk,发冷1 wk,发热4 d入院.曾在我院查WBC 4.5×109/L,N 0.60,L 0.4,体温波动在38~40℃.初步诊断"上呼吸道感染",用阿莫西林、VC银翘片、清热解毒冲剂等治疗无效.查体:T 38.9℃,BP面性12/8 kPa.全身皮肤无出血点,双眼球结膜轻度充血,咽部充血,软腭未见充血点,心肺腹部未见阳性体征.实验室检查:WBC 7.85 × 109/L,N 0.79,L 0.21,HGB 150g/L,PCL30×109/L,尿蛋白3.2g/L,流行性出血热抗体( ).诊断:流行性出血热.入院后立即按照流行性出血热的治疗原则给予抗病毒、抗渗出、抗出血治疗.具体包括卧床休息,给予高热量,多维生素,易消化饮食;维持水、电解质、酸碱及血浆渗透压平衡;给予大剂量(5 g)Vit.C和Vit.E.同时给予氢化可地松100 mg/d,稀释后缓慢静脉滴注.入院后3 d患者的尿量由450 mL/d增至750 mL/d,肌酐204.6μmol/L,BUN 13.3 mmol/L.5 d尿量增加至4000 mL/d.经综合治疗10 d,肌酐和BUN检查等正常,痊愈出院,随访1 mo未见异常.  相似文献   
90.
A new tissue-equivalent phantom material has been developed which also acts as a dosimeter. The new phantom material has a similar elemental composition to that of soft tissue and has a density 1.1 g/cm3. The phantom has an agar-gel base, and contains crystallized L-alpha-alanine which traps radiation-induced free radicals. Samples from the phantom were analyzed by an electron paramagnetic resonance (EPR) spectrometer and the intensity of the EPR signal was related to the absorbed dose. When calibrated, the phantom material acts as a dosimeter, with applications in radiation therapy.  相似文献   
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