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1.

Background:

Structural magnetic resonance imaging techniques are powerful tools for examining the effects of drug use on the brain. The nicotine and cannabis literature has demonstrated differences between nicotine cigarette smokers and cannabis users compared to controls in brain structure; however, less is known about the effects of co-occurring cannabis and tobacco use.

Methods:

We used voxel-based morphometry to examine gray matter volume differences between four groups: (1) cannabis-dependent individuals who do not smoke tobacco (Cs); (2) cannabis-dependent individuals who smoke tobacco (CTs); (3) cannabis-naïve, nicotine-dependent individuals who smoke tobacco (Ts); and (4) healthy controls (HCs). We also explored associations between gray matter volume and measures of cannabis and tobacco use.

Results:

A significant group effect was observed in the left putamen, thalamus, right precentral gyrus, and left cerebellum. Compared to HCs, the Cs, CTs, and Ts exhibited larger gray matter volumes in the left putamen. Cs also had larger gray matter volume than HCs in the right precentral gyrus. Cs and CTs exhibited smaller gray matter volume than HCs in the thalamus, and CTs and Ts had smaller left cerebellar gray matter volume than HCs.

Conclusions:

This study extends previous research that independently examined the effects of cannabis or tobacco use on brain structure by including an examination of co-occurring cannabis and tobacco use, and provides evidence that cannabis and tobacco exposure are associated with alterations in brain regions associated with addiction.  相似文献   
2.
Existing serological methods for diagnosis of leptospirosis are still unsatisfactorily due mainly to their low accuracy. In this study, serum samples of 18 clinically diagnosed-, IgM dipstick positive-, MAT positive-leptospirosis patients (group 1) were analyzed by IgG Western blotting against SDS-PAGE separated-whole cell homogenates of pathogenic and non-pathogenic Leptospira spp. belonging to 20 serovars of 15 serogroups. The samples of group 1 were collected from the patients at days 3 to 10 after the fever onset (fist samples). Second and third samples could be obtained from 4 patients. Sera of the 22 patients with other febrile illnesses (group 2) and 22 healthy counterparts (group 3) were used as patient- and normal- controls, respectively. Irrespective of the serovar or serogroup of the pathogenic Leptospira spp. used as antigen in the Western blotting, all of the 18 sera of patients with leptospirosis (group 1) gave characteristic diffuse antigen-antibody reactive bands located at approximately 35-38 and 22-26 kDa; and thus 100% diagnostic sensitivity of the Western blot assay. Some serum samples of the leptospirosis patients also reacted to components located at 80-100, approximately 70, 60, 54, and 48 kDa. More bands or the early recognized bands with increased intensity were observed when tested the second and third samples. The characteristic bands were not seen when homogenates of L. biflexa, serogroup Semaranga, serovar Patoc (saprophytic) and L. biflexa, serogroup Andamana, serovar Andamana (non-pathogenic but can infect host) were used in the assay. Sera of groups 2 and 3 did not react to the components at the seven locations implying 100% diagnostic specificity of the IgG Western blot assay. While awaiting validation with more patients' samples, the IgG Western Blot analysis aiming at the detection of the characteristic antigen-antibody reactive bands described in this study has high potential for early, rapid, simple and accurate diagnosis of human leptospirosis.  相似文献   
3.

BACKGROUND

The Centers for Medicare & Medicaid Services publicly reports risk-standardized mortality rates (RSMRs) within 30-days of admission and, in 2013, risk-standardized unplanned readmission rates (RSRRs) within 30-days of discharge for patients hospitalized with acute myocardial infarction (AMI), heart failure (HF), and pneumonia. Current publicly reported data do not focus on variation in national results or annual changes.

OBJECTIVE

Describe U.S. hospital performance on AMI, HF, and pneumonia mortality and updated readmission measures to provide perspective on national performance variation.

DESIGN

To identify recent changes and variation in national hospital-level mortality and readmission for AMI, HF, and pneumonia, we performed cross-sectional panel analyses of national hospital performance on publicly reported measures.

PARTICIPANTS

Fee-for-service Medicare and Veterans Health Administration beneficiaries, 65 years or older, hospitalized with principal discharge diagnoses of AMI, HF, or pneumonia between July 2009 and June 2012. RSMRs/RSRRs were calculated using hierarchical logistic models risk-adjusted for age, sex, comorbidities, and patients’ clustering among hospitals.

Results

Median (range) RSMRs for AMI, HF, and pneumonia were 15.1% (9.4–21.0%), 11.3% (6.4–17.9%), and 11.4% (6.5–24.5%), respectively. Median (range) RSRRs for AMI, HF, and pneumonia were 18.2% (14.4–24.3%), 22.9% (17.1–30.7%), and 17.5% (13.6–24.0%), respectively. Median RSMRs declined for AMI (15.5% in 2009–2010, 15.4% in 2010–2011, 14.7% in 2011–2012) and remained similar for HF (11.5% in 2009–2010, 11.9% in 2010–2011, 11.7% in 2011–2012) and pneumonia (11.8% in 2009–2010, 11.9% in 2010–2011, 11.6% in 2011–2012). Median hospital-level RSRRs declined: AMI (18.5% in 2009–2010, 18.5% in 2010–2011, 17.7% in 2011–2012), HF (23.3% in 2009–2010, 23.1% in 2010–2011, 22.5% in 2011–2012), and pneumonia (17.7% in 2009–2010, 17.6% in 2010–2011, 17.3% in 2011–2012).

Conclusions

We report the first national unplanned readmission results demonstrating declining rates for all three conditions between 2009–2012. Simultaneously, AMI mortality continued to decline, pneumonia mortality was stable, and HF mortality experienced a small increase.  相似文献   
4.
Chronic renal impairment can lead to bone deterioration and abnormal bone morphology, but whether hydronephrosis is associated with bone loss remains unclear. Herein, we aimed to use computer‐assisted bone histomorphometric technique to investigate microstructural bone changes in Imprinting Control Region (ICR) mice with a spontaneous mutation that was associated with bilateral nonobstructive hydronephrosis (ICR/Mlac‐hydro). The results showed that 8‐week‐old ICR/Mlac‐hydro mice manifested decreases in trabecular bone number and thickness, and an increased trabecular separation, thereby leading to a reduction in trabecular bone volume compared with the wild‐type mice. Furthermore, histomorphometric parameters related to both bone resorption and formation, that is, eroded surface, osteoclast surface, and osteoblast surface, were much lower in ICR/Mlac‐hydro mice than in the wild type. A decrease in moment of inertia was found in ICR/Mlac‐hydro mice, indicating a decrease in bone strength. In conclusion, ICR/Mlac‐hydro mice exhibited trabecular bone loss, presumably caused by marked decreases in both osteoblast and osteoclast activities, which together reflected abnormally low bone turnover. Thus, this mouse strain appeared to be a valuable model for studying the hydronephrosis‐associated bone disease. Anat Rec, 297:208–214, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
5.
Evaluation of the BACTEC MGIT 960 system for the recovery of mycobacteria   总被引:6,自引:0,他引:6  
We evaluated the BACTEC MGIT 960 system, which is a fully automated, non-invasive, continuous monitoring system for the growth and detection of mycobacteria. Including respiratory and other specimens, 1,742 specimens were processed and inoculated into the BACTEC MGIT 960 and the BACTEC 460 TB Systems, as well as onto Lowenstein-Jensen (L-J) media. A total of 104 isolates of mycobacteria were recovered from all culture systems. This included Mycobacterium tuberculosis complex, Mycobacterium avium-intracellulare (MAI) complex and other mycobacteria (MOTT). The isolation rates for M. tuberculosis complex and MAI complex were comparable for the BACTEC 460 (54.8% and 13.5%) and the BACTEC MGIT 960 (51.9% and 13.5%). The overall isolation rate was less for BACTEC MGIT 960 (76.9%) which was due to lesser number of MOTT isolates recovered from this system. The mean times to detection (TTD) for all mycobacteria were 9.3 days for the BACTEC MGIT, 14.6 days for the BACTEC 460 and 21.6 days for L-J. A significant difference was observed when TTD was tested in relation to degree of positivity in smears, with the BACTEC MGIT maintaining the short TTD even with less number of bacilli in the smear. The contamination rates were, 6.4% for BACTEC MGIT, 2.9% for BACTEC 460 and 12.1% for L-J medium. The BACTEC MGIT 960 system shows performances comparable to the BACTEC 460 and seems to be a dependable, user friendly system.  相似文献   
6.
7.
Children who have completed treatment for acute lymphoblastic leukaemia (ALL) are commonly followed up for the first 5 years with regular full blood counts (FBCs) to monitor for relapse of disease. There is little evidence to suggest that this practice improves the detection rate of unexpected relapse. Surveillance FBCs, performed on 43 children with relapsed ALL between 1990 and 1999, were analysed. Of the 42 relapses in children off therapy, only two were detected by an abnormal FBC. Routine FBCs in asymptomatic children off therapy lacks specificity in detecting unexpected relapses and maybe safely discontinued.  相似文献   
8.
Erythema toxicum neonatorum is a common, inflammatory skin reaction in healthy newborn infants characterized by an accumulation of activated immune cells in the lesions. Its etiology and physiologic significance are still unclear. The purpose of this study was to extend the search for possible inflammatory mediators of the rash. We performed immunohistochemistry on punch biopsy cryosections from lesions of four, 1-day-old infants and from four matched controls without rash, using antibodies against the water channel proteins aquaporin-1 (AQP1) and aquaporin-3 (AQP3), psoriasin, and the nitric oxide synthase (NOS) enzymes, neuronal NOS (nNOS), inducible NOS (iNOS), and endothelial NOS (eNOS). All sections from the lesions showed a dense, nodular cellular infiltrate located near the hair follicle. The vessels in the dermis showed a high incidence of AQP1 and eNOS. Strong staining for AQP1, AQP3, and psoriasin, as well as nNOS, iNOS, and eNOS were seen in the entire epidermal layer. The infiltrate in the dermis contained numerous cells expressing AQP1, AQP3, nNOS, iNOS, and eNOS. Double immunofluorescence staining showed that AQP3 was located in CD1a-expressing Langerhans cells and other dendritic cells in the dermis, as well as in CD14-expressing macrophages, CD15-expressing neutrophils, and EG2-expressing eosinophils surrounding the hair follicle. Our findings show that AQP1 and AQP3, psoriasin, and NOSs are involved in the activation of the skin immune system at birth.  相似文献   
9.
10.
Mammaglobin-A is exclusively expressed by breast cancer cells. Thus, mammaglobin-A-specific T cell immune responses may be useful for the design of new breast cancer-specific immunotherapies. We show herein that CD8+ T cells generated against recombinant mammaglobin-A-pulsed dendritic cells display a marked cytotoxic activity against mammaglobin-A-positive breast cancer cell lines. This study indicates the immunotherapeutic potential of this novel antigen for the treatment of breast cancer.  相似文献   
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