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61.
The purpose of the present investigation is to emphasize the application of hot-melt extrusion technique (HMET) for the preparation of sustained release matrix formulation of highly dosed, freely soluble drugs. In this study, sustained release multiple unit dosage of venlafaxine hydrochloride (VH) was prepared by HMET. Custom design was used to screen the effect of four factors-type of polymer (ethylcellulose and eudragit RSPO) (X 1), amount of polymer (X 2), type of plasticizer (DBS, ATBC, TEC, and PEG) (X 3), and plasticizer concentration (X 4), on the drug release at 8 h (Y1) and machine torque (Y2). The experiments were carried out according to a four-factor 16-run statistical model and subjected to 12-h dissolution study in purified water. The significance of the model was indicated by ANOVA. Results of in vitro release study indicate that formulations prepared with higher amount of ethylcellulose and DBC show significant retardation at 8 h. The result shows that increase in concentration of polymer with the combination of water insoluble plasticizer (DBS and ATBC) has better sustained release while increasing concentration of TEC and PEG results faster in vitro release. Besides that increase in plasticizer concentration helps in reducing the melt temperature and machine torque. The in vivo study was performed, and formulations were compared using area under the plasma concentration-time curve (AUC0-∞), time to reach peak plasma concentration (Tmax), and peak plasma concentration (Cmax). The drug release profiles of extrudes were found to fit both diffusion and surface erosion models. Further to this, scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction analysis of the hot-melt extrudates demonstrated that VH remained crystalline and was homogeneously dispersed throughout the polymer matrix.  相似文献   
62.

Biofilms are responsible for causing 80% of human infections including chronic infections like-cystic fibrosis, endocarditis and osteomyelitis. The growing ability of the biofilm to resist most of the available antibiotics has caused a serious threat to different life forms. Plenty of research work has already been reported, and some are ongoing to combat this serious health issue worldwide. Recent developments in nanotechnology have given a great boost in dealing biofilm infections. The unique size-dependent properties for antibacterial and antibiofilm activities provide the nanoparticles better options to eradicate biofilms. Here, the authors have discussed the basic biology of bacterial biofilm and their impact on human health. In addition, different nanotechnology-based strategies to overcome serious health issues caused by biofilm infections have been highlighted.

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63.
This study presents a longitudinal comparison of motor nerve conduction velocities (MCVs) in patients with Charcot-Marie-Tooth type 1A with proven duplication of a segment of chromosome 17p11.2p12. Results were compared for 8 CMT1A duplication patients from one family whose MCV measurements were taken 22 years apart (1967 and 1989). Measurements from a total of seven median motor and five peroneal motor MCVs were compared. Median MCVs showed a slight reduction that averaged 2.2 m/s, and peroneal MCVs showed an average decrease of 3.0 m/s. In addition, mild objective increase in limb weakness was seen in only 1 of 8 patients and subjective symptoms of gradual worsening of leg strength were noted in half the patients over the same period. In this study of a small group of CMT1A patients with proven segmental duplication of chromosome 17p11.2p12, the motor conduction velocities and clinical motor exam did not change significantly over 22 years. © 1996 John Wiley & Sons, Inc.  相似文献   
64.
Neuronal mitochondrial dysfunction increases inflammatory mediators and leads to free radical generation and anti-oxidant enzymatic alterations,which are major neuropathological hallmarks responsible for autism.Mitochondrial dysfunction in autism is associated with decreased ATP levels due to reduced levels of cyclic adenosine monophosphate.Rat models of autism were established by intracerebroventricular injection of propionic acid.These rat models had memory dysfunction,decreased muscle coordination and gait imbalance.Biochemical estimation of propionic acid-treated rats showed changes in enzyme activity in neuronal mitochondrial electron transport chain complexes and increases in pro-inflammatory cytokines,oxidative stress and lipid biomarkers.Oral administration of 10,20 and 30 mg/kg adenylate cyclase activator forskolin for 15 days reversed these changes in a dose-dependent manner.These findings suggest that forskolin can alleviate neuronal mitochondrial dysfunction and improve neurological symptoms of rats with autism.This study was approved by the RITS/IAEC,SIRSA,HARYANA on March 3,2014(approval No.RITS/IAEC/2014/03/03).  相似文献   
65.
The study aims to examine the knowledge and the practice of the precautionary measures taken by older adults in Hong Kong against the outbreak of severe acute respiratory syndrome (SARS). Overall, more than half the participants responded correctly that droplet transmission is one of the main transmission routes of SARS. Those who received formal education demonstrated that they acquired greater knowledge of the sources and precautionary measures for SARS. The types of precautionary measures used and the factors affecting their behaviours were discussed. The results of the study could help the health-care professionals develop appropriate health promotion and disease prevention programmes for older adults.  相似文献   
66.
A new phenylpropanoid glycoside, dolichandroside‐A, together with seven known compounds α‐lapachone, lapachol, aloesaponarin II, 8‐hydroxydehydroiso‐α‐lapachone, β‐sitosterol, 3,8‐dihydroxydehydroiso‐α‐lapachone and verbascoside were isolated from the active ethyl acetate soluble extract of heartwood of Dolichandrone falcata. All except for dolichandroside‐A are known compounds, but have been isolated for the first time from this plant. The structure of all these compounds was determined on the basis of 1D‐ and 2D‐NMR spectral data. All the isolates were tested for α‐glucosidase inhibitory and DPPH radical scavenging activity. This is the first report identifying DPPH scavenging activity and α‐glucosidase inhibitory activity in D. falcata. Furthermore, along with a new compound, dolichandroside‐A, this study also assigns for the first time α‐glucosidase inhibitory activity to verbascoside and aloe saponarin‐II. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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The involvement of the cerebellum in Legionnaires' disease has been noted in occasional case reports, but there have been no reviews on this subject to date. We report a previously healthy patient who contracted Legionella pneumonia and developed profound cerebellar dysfunction during his illness. He was treated with antibiotics with improvement of his pneumonia, but his cerebellar symptoms persisted. We review 29 case reports of cerebellar dysfunction in Legionnaires' disease and summarize the clinical course, cultures, cerebrospinal fluid analyses, and neuroimaging. Finally, possible methods of pathogenicity are discussed including data regarding direct bacterial invasion, toxin production, and immune-mediated mechanisms.  相似文献   
70.
The combination of kidney paired donation (KPD) with desensitization represents a promising method of increasing the rate of living donor kidney transplantation (LDKT) in immunologically challenging patients. Patients who are difficult to match and desensitize due to strong donor specific antibody are may be transplanted by a combination of desensitization and KPD protocol with more immunologically favorable donor. We present our experience of combination of desensitization protocol with three-way KPD which contributed to successful LDKT in highly sensitized end stage renal disease patient. All recipients were discharged with normal and stable allograft function at 24 mo follow up. We believe that this is first report from India where three-way KPD exchange was performed with the combination of KPD and desensitization. The combination of desensitization protocol with KPD improves access and outcomes of LDKT.  相似文献   
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