Joint application of independent component analysis and non-stationary fluctuation analysis for studying the mechanisms of the early phase of long-term potentiation in the rat hippocampus

Interest in studies of synaptic plasticity have led to the development of specific methods for analyzing evoked postsynaptic currents: quantum analysis, component analysis, non-stationary fluctuation analysis, etc. However, the use and interpretation of these methods are not always consistent, which leads to the acquisition of contradictory results from similar experiments. In the present study, simulations were used to analyze the influences of the heterogeneity of the shapes of postsynaptic currents on the results obtained by non-stationary fluctuation analysis. Assessment of postsynaptic channel conductivity was found to depend on the number of synapses involved in generating the response. It is hypothesized that the increase in the assessment of AMPA channel conductivity reported in the literature in conditions of long-term potentiation may be related to changes in the synaptic composition of postsynaptic currents. The hypothesis was tested using a new method for independent component analysis. Studies using the simulation showed that the joint application of this method and non-stationary fluctuation analysis avoids errors of this type. The procedures developed here were applied to data obtained from physiological experiments; the results of this exercise provided general support for the hypothesis. __________ Translated from Zhurnal Vysshei Nervnoi Deyatel’nosti imeni I. P. Pavlova, Vol. 55, No. 3, pp. 293–304, May–June, 2005.     

Clinical Significance and Outcome of Gastric Mucosal Erosions: A Long-Term Follow-Up Study

Our purpose was to evaluate the long-term clinical significance of gastric erosions. A series of 117 patients with gastric erosions without peptic ulcer disease, and matched controls were studied in 1974–1979. All available subjects were reinvestigated 17 years later, including detailed clinical history and laboratory analysis. At follow-up, erosions were still more prevalent (39%; 20/50) in the erosion group than in the controls (11; 7/66). In Helicobacter pylori–positive participants, peptic ulcer or a scar was more common in the erosion group (17%; 9/52) than in controls (5%; 3/66). Overall malignancy rate was higher in controls (15%; 17/117) than in erosion group (5%; 6/117; P = .025), but no other differences were seen between the groups or related with current erosion. We conclude that a significant proportion of gastric erosions are chronic or recurrent but mostly without serious complications. However, H. pylori–positive patients with erosions have significant risk to develop a peptic ulcer.     

Purkinje cell activity during classical eyeblink conditioning in decerebrate guinea pigs

Purkinje cells are the sole output from the cerebellar cortex and play a critical role during classical eyeblink conditioning. The present study revealed for the first time a learning-related change in individual Purkinje cell activity during successive eyeblink conditioning in decerebrate guinea pigs which permitted continuous single unit recording from the simplex lobe of the cerebellar cortex. The pair-conditioned group received paired presentation of the conditioned stimulus (CS) and unconditioned stimulus (US) until the frequency of the conditioned response (CR) exceeded 80%. The control group received a comparable number of the CS and US in a pseudorandom fashion. Responses of Purkinje cells to the CS were classified into four types: excitatory, inhibitory, a combination of the two, or no response. Approximately half of the recorded cells from both groups changed their response type at various conditioning stages. The firing frequency of a Purkinje cell to the CS showed a tendency to decrease in the pair-conditioned group, while it had a tendency to increase in the pseudoconditioned group. This learning-related difference in change of response type was attributable to a difference in the change between the no response and the inhibitory response types. Correlation analysis of the temporal pattern between the neural activity and the CR revealed that most of the cells that developed an inhibitory response by paired conditioning acquired the CR-related temporal pattern. These results suggest that the learning-related Purkinje cells gain an inhibitory response with a temporal pattern correlated with the CR topography.     

Immigration and the Direct Long-Term Care Workforce: Implications for Education and Policy

ABSTRACT

The escalating demand for trained direct long-term care (DLTC) workers, those individuals with the most sustained direct contact with vulnerable older adults in homes and facilities, is a consequence of our rapidly aging population. Research documents the present and projected shortages of DLTC workers, and developed nations are increasingly turning to immigrant women to fulfill these workforce needs. The authors identify international trends that influence the availability of these workers. Following a broad overview of the DLTC workforce, they turn to a specific examination of immigrants working in long-term care settings in the United States. The authors raise a number of questions about this changing workforce profile. They outline four ways that institutes of higher education can help improve the DLTC workforce in the United States and suggest that colleges and universities work in partnership with policy makers and the long-term care industry to this end.     

Pediatric Emergency Departments are More Likely Than General Emergency Departments to Treat Asthma Exacerbation With Systemic Corticosteroids

Objective. To determine whether systemic corticosteroids are under-prescribed (as measured by current NIH treatment guidelines) for children in the United States seen in the emergency department (ED) for acute asthma, and to identify factors associated with prescribing systemic corticosteroids. Methods. We used data from the 2001–2007 National Hospital Ambulatory Medical Care Survey. The study population was children ≤18 years old in the ED with a primary diagnosis of asthma (ICD-9-CM code 493.xx) who received bronchodilator(s). The primary outcome was receipt of a systemic corticosteroid in the ED. Independent variables included patient-level (e.g., demographics, insurance, fever, admission), physician-level (provider type, ancillary medications and tests ordered), and system-level factors (e.g., ED type, geographic location, time of day, season, year). We used multivariable logistic regression techniques to identify factors associated with systemic corticosteroid treatment. Results. Systemic corticosteroids were prescribed at only 63% of pediatric acute asthma visits to EDs. Over the study period, there was a trend toward increasing systemic corticosteroid use (p for trend = .05). After adjusting for potential confounders, patients were more likely to receive systemic corticosteroids when treated in pediatric EDs than in general EDs (OR = 2.45; 95% CI: 1.26–4.77).Conclusion. Systemic corticosteroids are under-prescribed for children who present to EDs with acute asthma exacerbations. Pediatric EDs are more likely than general EDs to treat asthma exacerbations with systemic corticosteroids. Differences in the process of care in pediatric ED settings (compared to general EDs) may increase the likelihood of adherence to NIH treatment guidelines.     

Long-term outcome following placement of percutaneous endoscopic gastrostomy in younger and older patients

Objective. Percutaneous endoscopic gastrostomy (PEG) is the method of choice in maintaining enteral nutrition in patients with swallowing and nutritional disorders of different etiology. The aim of this study was to assess the long-term outcome of patients following placement of a PEG. Material and methods. All patients who received a PEG between October 1999 and September 2000 were included in this prospective study. Long-term function, replacement or removal of the PEG, complications and survival of the patients were analyzed in group A (younger than 75 years) and group B (75 years or older). Results. The indications for PEG placement in group A (54 patients, mean age 54.5 years) were neurological (66.7%) and malignant (31.5%) disorders, whereas in group B (40 patients, mean age 81 years) the indications were predominantly neurological diseases (87.5%). The majority of patients (91 of 94 patients; 96.8%) could be followed long term or until death. In group A, 46 patients (85.2%) had uncomplicated long-term function of their PEG and interventions were necessary in only 8 patients. Removal of the PEG was possible during the course in 17 patients (31.5%). In group B, uncomplicated long-term function was observed in 34 patients (85%) and interventions were required in only 6 patients. Removal of the PEG was not possible in group B. Survival rates for 1-, 2- and 5 years in group A were 73.9%, 61.8% and 43.9%, respectively, and in group B 41.4%, 31.9% and 15.9%, respectively; the difference was statistically significant (p=0.002). Conclusions. Excellent long-term function of PEG was seen in this study of 94 consecutive patients, and interventions were necessary only in a minority of patients. The prognosis for older patients was worse; however, the 2-year survival rate of 32% justified the PEG insertion.     

心肺联合移植1例术后8.5年随访报告

对1例健康生存8.5年心肺移植患者进行总结分析。2003年9月20日湘雅二医院为1例室间隔缺损并重度肺动脉高压的患者施行心肺联合移植术。分别采用1500 mL改良St.Thomas心脏停搏液和3000 mL改良LPD液保护供体心肺。术后抗排斥反应,在诱导期使用甲泼尼龙+抗人淋巴细胞球蛋白治疗,稳定期采用环孢素A+骁悉+泼尼松龙三联免疫治疗。至2007年改为骁悉500 mg+FK506 4 mg,均每天2次。定期复查超声心动图、FK506血药浓度。随访时患者存活已超过8.5年。心功能恢复为(NYH A)I～II级,左心室射血分数61%～74%;提示心肺联合移植是治疗心肺功能衰竭的有效方法,良好心肺保护、正确术后处理是心肺联合移植患者长期存活的关键。     

南京地区19家综合性医院鲍曼不动杆菌抗感染药物用药趋势分析

目的:分析2007~2010年南京地区19家综合性三级和二级医院鲍曼不动杆菌(Ab)抗感染药物使用趋势,为评价临床合理用药提供依据?方法:根据限定日剂量(DDD)计算7类15种抗菌药物的用药频度,采用SPSS17.0软件对用药趋势进行线性回归分析?结果:三级医院碳青霉烯类?喹诺酮类?哌拉西林/他唑巴坦用药频度(DDDs/1 000)呈增长趋势,头孢哌酮/舒巴坦呈减少趋势;二级医院碳青霉烯类?四环素类?头孢菌素类?舒巴坦和他唑巴坦酶抑制剂用量均为增长趋势;19家医院碳青霉烯类?四环素类?哌拉西林/他唑巴坦及抗菌药物总用药频度为增长趋势?三级医院平均每半年所有抗菌药物用药频度均大于二级医院,仅环丙沙星小于二级医院?结论:19家医院每种和总碳青霉烯类?哌拉西林/他唑巴坦和总抗菌药物用药频度显著增加,需加强本地区感染控制以及抗菌药物临床合理应用?     

Trends in Substance Abuse and Infectious Disease Over 20 Years in a Large Methadone Maintenance Treatment (MMT) Clinic in Israel

ABSTRACT

Background: The objective was to study substance abuse, infectious disease, and patient outcomes (retention and substance abuse abstinence) over 2 decades in a large methadone maintenance treatment (MMT) facility within a tertiary-referral medical center.Methods: Prevalence of substance abuse was determined monthly between 1993 (35 patients) and 2013 (350 patients) based on observed random urine tests. On entry, patients were tested for hepatitis C and human immunodeficiency virus (HIV) antibodies. One-year retention and substance abuse abstinence were calculated. Results: At admission, mean age and rate of cocaine and benzodiazepines abuse increased over the years, with no change in the prevalence of hepatitis C (50%) and HIV (<10%). Retention rate increased (P = .008) (range: 42.9%–92.4%; overall: 76.2%) and opiate abstinence also increased (P = .006) (range: 49.1%–85.7%; overall: 68.1%), reflecting outcome improvement over the years.Conclusions: Outcome improvement could be attributed to the staff's growing experience and improvements in treatment but also to changes in patient characteristics over the past 2 decades.