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771.
The aim of the study is to determine the clinical features and outcomes of cocaine users admitted to the hospital after cardiac arrest and compare them with nonusers. Cocaine is associated with cardiovascular complications, including ventricular arrhythmias; however, resuscitated cardiac arrest in relation to cocaine use is not a well-defined clinical entity. We reviewed available hospital charts at San Francisco General Hospital with the International Classification of Diseases, Ninth Revision diagnosis of cardiac arrest and cocaine use from 1994 to 2006. Clinical features and outcomes of cocaine users were compared with those of randomly selected control patients and age-matched controls with resuscitated cardiac arrest without cocaine use. We identified 22 patients with resuscitated cardiac arrest in the setting of cocaine use. Their average age was 42 +/- 10 years, >20 years younger than nonusers (68 +/- 16 years, p <0.01). After cardiac arrest, 12 of 22 patients (55%) who used cocaine had complete neurologic recovery in contrast to only 3 of 20 unmatched controls (15%, p <0.01) and 7 of 41 age-matched controls (17%, p <0.01). Only 10 of 22 cocaine users (46%) died compared with 15 of 20 unmatched controls (75%, p = 0.05) and 32 of 41 age-matched controls (78%, p <0.01). In a combined analysis of all patients, cocaine use was the only significant predictor of neurologic recovery (p <0.01) and survival (p <0.01). In conclusion, cocaine use is associated with cardiac arrest. In patients with cardiac arrest, cocaine users are younger than nonusers and more likely to survive with neurologic recovery, even compared with age-matched controls with cardiac arrest.  相似文献   
772.
773.
Pharmaceutical, cellular and genetic therapies for Huntington's disease   总被引:2,自引:0,他引:2  
HD (Huntington's disease) is a devastating neurodegenerative disorder caused by a polyglutamine expansion in the gene encoding the huntingtin protein. Presently, there is no known cure for HD and existing symptomatic treatments are limited. However, recent advances have identified multiple pathological mechanisms involved in HD, some of which have now become the focus of therapeutic intervention. In this review, we consider progress made towards developing safe and effective pharmaceutical-, cell- and genetic-based therapies, and discuss the extent to which some of these therapies have been successfully translated into clinical trials. These new prospects offer hope for delaying and possibly halting this debilitating disease.  相似文献   
774.
To date, glyceroneogenesis has only been described in mammals but we demonstrate in this paper that it could exist in the invertebrate Schistosoma mansoni, the parasitic helminth transmitted by fresh water molluscs and responsible for the major human endemic disease, schistosomiasis. Glyceroneogenesis is a phosphoenolpyruvate carboxykinase (PEPCK)-dependent process by which glycerol can be produced from precursors like glutamine and therefore represents a truncated gluconeogenic pathway. We have previously demonstrated the possible central role of glutamine in mollusc-schistosome interactions. In this work, we show that glutamine effectively promotes in vitro survival and protein synthesis in sporocysts, the intramolluscan larval stages of S. mansoni, possibly through its role as an energy source. However, the demonstration that PEPCK is massively expressed in these larval forms as compared to adult parasites, together with the observation that 3-mercaptopicolinate, a specific inhibitor of PEPCK, significantly reduces the effect of glutamine on sporocyst growth, suggest that glutamine could also be used for glucose or glycerol production. Results of [14C] glutamine incorporation confirmed that neosynthesis of glucose and mainly of glycerol occurred in sporocysts and was dependent on PEPCK activity. Therefore, our results strongly indicate that glyceroneogenesis could exist in schistosomes. Several hypotheses can be proposed concerning the importance of glycerol for the adaptation of this helminth to its host osmotic and energetic environment.  相似文献   
775.
Background: Dental practitioners are at high risk of occupational ocular incidents during their daily work practice. The aim of this study was to assess the prevalence, pattern and determinants of ocular incidents and to establish the use of eye protection by dental staff in southwestern Saudi Arabia. Methods: This multicentre cross-sectional study was conducted among dental practitioners working in private, military and Ministry of Health dental clinics in southwestern Saudi Arabia. A predesigned self-report questionnaire was used to elicit information on demographics, splash or foreign body ocular incidents, postincident practices and use of eye protection. Results: Of the 233 dental practitioners examined, 29.6% and 51.1% reported ocular incidents as a result of foreign bodies and fluid splashing, respectively. The risk of ocular incidents as a result of fluid splashing was significantly higher in the absence of postgraduate qualification [odds ratio (OR) = 3.04, 95% confidence interval (95% CI): 1.70–5.43], poor compliance with wearing eye protection (OR = 2.52, 95% CI: 1.49–4.28) and long work hours (OR = 2.16, 95% CI: 1.17–3.96). The most frequent postexposure practice was to rinse eyes under running water (87.5%). Approximately 4.2% and 9.2% of dental practitioners reported incidents of ocular injury and infection, respectively, and 14% reported that they never wore any eye protection. Conclusion: Occupational ocular incidents as a result of splashing and foreign bodies are relatively common among dental practitioners in southwestern Saudi Arabia. The absence of postgraduate qualification, poor compliance with wearing eye protection and working long hours are predictors of ocular incidents. Awareness about eye safety is therefore considered mandatory for dental practitioners in southwestern Saudi Arabia. Also, dental clinic administrators should provide and promote the use of eye protection.Key words: Dentists, occupational, ocular incidents, splash, foreign body, injury, infection  相似文献   
776.
Putative MRI markers of iron in deep gray matter have demonstrated age related changes during discrete periods of healthy childhood or adulthood, but few studies have included subjects across the lifespan. This study reports both transverse relaxation rate (R2*) and quantitative susceptibility mapping (QSM) of four primary deep gray matter regions (thalamus, putamen, caudate, and globus pallidus) in 498 healthy individuals aged 5–90 years. In the caudate, putamen, and globus pallidus, increases of QSM and R2* were steepest during childhood continuing gradually throughout adulthood, except caudate susceptibility which reached a plateau in the late 30s. The thalamus had a unique profile with steeper changes of R2* (reflecting additive effects of myelin and iron) than QSM during childhood, both reaching a plateau in the mid‐30s to early 40s and decreasing thereafter. There were no hemispheric or sex differences for any region. Notably, both R2* and QSM values showed more inter‐subject variability with increasing age from 5 to 90 years, potentially reflecting a common starting point in iron/myelination during childhood that diverges as a result of lifestyle and genetic factors that accumulate with age.  相似文献   
777.
778.

BACKGROUND

Many patients cannot afford sterile dressings. In St John, New Brunswick, clean dressings have been used instead of sterile dressings for years, with no apparent ill effects. No previous studies have compared the sterility and cost of clean versus sterile dressing materials.

OBJECTIVES

The goals of the present study were to answer the following questions: how much more sterile are sterile dressings than clean dressings; and how much does this extra sterility cost?

METHODS

Sterility and cost of sterile gauze, panty liners, sanitary napkins, diapers and Coban tape (3M, USA) were compared. Samples, 2 cm × 2 cm in size, were cut out of each material under aseptic conditions, and delivered to the microbiology laboratory in sterile urine containers. The samples were then cultured and organisms were identified using conventional means.

RESULTS

The cost for one month, using one 20 cm × 5 cm wound dressing daily, was calculated and compared with panty liners ($2.43), sanitary napkins ($5.55), diapers ($9.39) and Coban tape ($0.66), which were much cheaper than sterile dressings ($16.50). How sterile were the dressings? None of the 20 sanitary napkins grew bacteria, one of the 20 panty liners grew bacteria (coagulase-negative Staphylococcus), two of 20 sterile dressings grew bacteria (one coagulase-negative Staphylococcus and one nonhemolytic Streptococcus), 15 of 20 diapers grew bacteria (all bacillus) and two of five Coban rolls grew bacteria (one bacillus and one coagulase-negative Staphylococcus).

CONCLUSION

The panty liners, sanitary napkins and Coban tape studied were cheaper than, and had a comparible sterility with, the sterile gauze examined.  相似文献   
779.
Analytical validation of a new liquid chromatographic-mass spectrometric (LC-MS) method for determination of total amount of ketotifen (unchanged and conjugated) in human plasma is presented. Pizotifen was used as an internal standard. An enzyme hydrolysis of conjugated ketotifen was conducted with a combination of beta-glucuronidase and aryl sulfatase. After enzyme hydrolysis a liquid-liquid extraction was performed as a cleaning step. The quantitative determination was obtained using selected ion monitoring (SIM) LC-MS. Chromatographic condition was a combination of reverse phase gradient system and a switching column technique. A satisfactory hydrolysis, acceptable accuracy, improved precision in the linear range from 0.5 to 20.0 ng/ml plasma, absolute recovery of 98.04% for ketotifen and 95.13% for pizotifen and stability for 7 months at -20 degrees C have been achieved.  相似文献   
780.
The degeneration of dopaminergic cells in dementia with Lewy bodies (DLB) may provide an important source of additional free radical generation. As a result, the oxidative stress status in DLB could be significantly enhanced. Subsequently, the levels of endogenous antioxidants, which are an indirect measure of free radical activities, may be different in DLB patients when compared with Alzheimer's disease (AD) patients and controls. In this preliminary study, we measured the activities of superoxide dismutase (SOD), catalase (CAT), glutathione (GLU) and total antioxidant capacity in the blood of DLB, AD and control subjects. The state of nigrostriatal dopaminergic system was also assessed in vivo by using a radioactive ligand with an affinity for the dopamine pre-synaptic receptors and by imaging with single-photon emission tomography. Data obtained showed a decrease in dopamine pre-synaptic receptors in all the brain regions of DLB patients. The levels of SOD did not differ significantly between DLB, AD and control subjects. However, GLU levels were significantly higher in the DLB patients when compared with AD patients (p < 0.05) and controls (p < 0.01). CAT blood levels were also higher in DLB when compared with AD, but this did not reach statistical significance. The results suggest that a different oxidative stress state may exist in DLB. This may occur due to increased free radical production from the degeneration of dopaminergic cells and auto-oxidation of dopamine, the availability of which may be maintained in early-stage DLB disease as a result of the compensatory increase in its turnover from the remaining dopaminergic cells.  相似文献   
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