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61.
OBJECTIVES: The relation between the occurrence of pacing-induced mechanical alternans and prognosis in patients with mild-to-moderate idiopathic dilated cardiomyopathy (IDCM) in sinus rhythm was investigated prospectively. The myocardial expression of genes for Ca2+-handling proteins in such patients was also examined. BACKGROUND: Mechanical alternans occurs in some patients with severe heart failure, but the relation between the occurrence of mechanical alternans and prognosis in patients with IDCM has remained unknown. METHODS: Left ventricular (LV) pressure was measured during atrial pacing, and LV endomyocardial biopsy specimens were collected in 36 IDCM patients and 8 controls. Idiopathic dilated cardiomyopathy patients were divided into two groups consisting of 22 individuals who did not develop mechanical alternans at heart rates up to 140 beats/min (group A) and of 14 individuals who did (group B). The patients were followed up for a mean of 3.7 years. RESULTS: There was no significant difference in LV ejection fraction or the plasma concentration of brain natriuretic peptide between groups A and B. The myocardial abundance of ryanodine receptor 2 messenger ribonucleic acid (mRNA) was significantly lower in groups A and B than in controls, whereas that of sarcoplasmic reticulum Ca2+-ATPase mRNA was significantly lower in group B than in group A or controls. Stepwise multivariate analysis identified pacing-induced mechanical alternans as the strongest predictor of cardiac events. Event-free survival in group A was significantly greater than that in group B. CONCLUSIONS: The occurrence of pacing-induced mechanical alternans is a potentially useful indicator of poor prognosis in patients with mild-to-moderate IDCM in sinus rhythm.  相似文献   
62.
Oxidative challenge can compromise intestinal growth and death responses. This study examines the effect of chronic consumption of subtoxic levels of peroxidized lipids on intestinal redox balance and turnover and the effect of glutathione (GSH) supplementation. Male Sprague-Dawley rats were fed standard rat chow or 4% peroxidized menhaden oil chow (2–8 weeks). Intestinal GSH and glutathione disulfide (GSSG), GSH synthetic and redox enzymes as well as proliferative (ornithine decarboxylase, ODC) and apoptotic activities were evaluated. Chronic peroxide intake did not affect overall animal growth, but decreased intestinal GSH/GSSG ratio that directly correlated with decreased GSH and increased GSSG, and suppressed peak circadian ODC activities and postprandial mucosal apoptosis. Supplementation with GSH restored the mucosal GSH/GSSG ratio and abrogated the peroxide-induced suppression of intestinal cell turnover. Collectively, the results show that chronic lipid peroxide consumption induces intestinal GSH redox imbalance that interferes with regulation of enterocyte death and proliferation in vivo. These disruptive effects of lipid peroxides were reversed by GSH supplementation in accordance with the normalization of tissue GSH/GSSG redox balance.  相似文献   
63.
Environmental Control Units (ECU) are devices or a system that allows a person to control appliances in their home or work environment. Such system can be utilized by clients with physical and/or functional disability to enhance their ability to control their environment, to promote independence and improve their quality of life. Over the last several years, there have been an emergence of several inexpensive, commercially-available, voice activated smart speakers into the market such as Google Home and Amazon Echo. These smart speakers are equipped with far field microphone that supports voice recognition, and allows for complete hand-free operation for various purposes, including for playing music, for information retrieval, and most importantly, for environmental control. Clients with disability could utilize these features to turn the unit into a simple ECU that is completely voice activated and wirelessly connected to appliances. Smart speakers, with their ease of setup, low cost and versatility, may be a more affordable and accessible alternative to the traditional ECU.
  • Implications for Rehabilitation
  • Environmental Control Units (ECU) enable independence for physically and functionally disabled clients, and reduce burden and frequency of demands on carers.

  • Traditional ECU can be costly and may require clients to learn specialized skills to use.

  • Smart speakers have the potential to be used as a new-age ECU by overcoming these barriers, and can be used by a wider range of clients.

  相似文献   
64.
X-ray radiotherapy activates tumor antigen-specific T-cell responses, and increases in the serum levels of high mobility group box 1 (HMGB1) induced by X-ray irradiation play a pivotal role in activating anti-tumor immunity. Here, we examined whether carbon-ion beams, as well as X-rays, can induce HMGB1 release from human cancer cell lines. The study examined five human cancer cell lines: TE2, KYSE70, A549, NCI-H460 and WiDr. The proportion of cells surviving X- or carbon-ion beam irradiation was assessed in a clonogenic assay. The D10, the dose at which 10% of cells survive, was calculated using a linear–quadratic model. HMGB1 levels in the culture supernatants were assessed by an ELISA. The D10 dose for X-rays in TE2, KYSE70, A549, NCI-H460 and WiDr cells was 2.1, 6.7, 8.0, 4.8 and 7.1 Gy, respectively, whereas that for carbon-ion beams was 0.9, 2.5, 2.7, 1.8 and 3.5 Gy, respectively. X-rays and carbon-ion beams significantly increased HMGB1 levels in the culture supernatants of A549, NCI-H460 and WiDr cells at 72 h post-irradiation with a D10 dose. Furthermore, irradiation with X-rays or carbon-ion beams significantly increased HMGB1 levels in the culture supernatants of all five cell lines at 96 h post-irradiation. There was no significant difference in the amount of HMGB1 induced by X-rays and carbon-ion beams at any time-point (except at 96 h for NCI-H460 cells); thus we conclude that comparable levels of HMGB1 were detected after irradiation with iso-survival doses of X-rays and carbon-ion beams.  相似文献   
65.
66.
Miliary tuberculosis is a potentially lethal type of tuberculosis that results from the hematogenous dissemination of Mycobacterium tuberculosis bacilli. We herein describe the case of a 34-year-old man that presented with a one-month history of cough and fever, while his sputum smear results were negative. Chest computed tomography revealed bilateral centrilobular ground-glass opacification (GGO), suggestive of hypersensitivity pneumonitis; thus, bronchoscopy was performed. Cryobiopsy specimens revealed necrotic granulomas. A re-examination of sputum after bronchoscopy identified Mycobacterium tuberculosis, and miliary tuberculosis was diagnosed. A cryobiopsy might be useful for diagnosing miliary tuberculosis pathologically, particularly when miliary nodules may be masked by GGO.  相似文献   
67.
Ethambutol-induced optic neuropathy (EON) is a well-known complication, although low-dose ethambutol seldom causes EON. An 85-year-old man with non-tuberculous mycobacterial lung disease was taking antibiotics, including low-dose ethambutol. On day 85 of treatment, the diagnosis of EON was made. Despite prior discontinuation, his best corrected visual acuity drastically deteriorated from 20/17 (right eye) and 20/20 (left eye) to 20/330 (right eye) and 20/1,000 (left eye) within 3 weeks, and this symptom did not resolve. To our knowledge, there have been no reported cases with drastically progressing and irreversible EON even after the withdrawal of low-dose and short-term ethambutol.  相似文献   
68.
69.
Summary This case concerns a 20-year-old male patient with an approximate 10-year history of recurrent and severe abdominal pain radiating to the back. Endoscopic retrograde cholangiopancreatography revealed a short obstructing stenosis of the main pancreatic duct in the head of the pancreas, marked and tortuous dilatation of the prestenotic portion of the main pancreatic duct and its side branches, and a filling defect in the side branch in the body of the gland. Pancreaticojejunostomy was performed to induce decompression of the pancreatic duct. Histology of the pancreas showed advanced chronic pancreatitis. Three nonopaque concretions were obtained at operation. The largest one, which was milky white in appearance and elastic and soft in consistency, proved to be made up of protein. The concretion was rich in acidic amino acids, but poor in basic or aromatic residues. The molar composition of amino acids in the concretion was, in decreasing order, aspartic acid, serine, valine, glycine, and glutamic acid. Powder x-ray diffractometry revealed no crystalline structures.  相似文献   
70.
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