Reward processing in trichotillomania and skin picking disorder

Brain Imaging and Behavior - Trichotillomania (hair pulling disorder) and skin picking disorder are common and often debilitating mental health conditions, grouped under the umbrella term of body...     

A Mixed-Methods Evaluation of a Community-Based Behavior Change Program to Improve Maternal Health Outcomes in the Upper West Region of Ghana

Background: The Community Benefits Health (CBH) program introduced a community-based behavior change intervention to address social norms and cultural practices influencing maternal health and breastfeeding behaviors in rural Ghana. The purpose of this study was to determine if CBH influenced maternal health outcomes by stimulating community-level support in woman’s social networks.

Methods: A mixed-methods study was conducted to evaluate changes in six antenatal/postpartum care, birth attendance, and breastfeeding behaviors in response to the CBH intervention and to assess how the program was implemented and to what extent conditions during implementation influenced the results.

Results: We found increases in five of the six outcomes in both the intervention and control areas. Qualitative findings indicated that this may have resulted from program spillover. We considered the dose of exposure to program activities and found that women were significantly more likely to practice maternal health behaviors with increased exposure to program activities while controlling for study area and time.

Conclusions: Overall, we determined that exposure to the CBH program significantly improved uptake of three of the six study outcomes, indicating that efforts aimed at increasing communication across women and their social networks may lead to improved health outcomes.     

A substituted tetrahydro-tetrazolo-pyrimidine is a specific and novel inhibitor of hepatitis B virus surface antigen secretion

The high levels of hepatitis B virus (HBV) surface antigen (HBsAg)-bearing subviral particles in the serum of chronically infected individuals are thought to play a role in suppressing the HBV-specific immune response. Current therapeutics are not directed at reducing this viral antigenemia; thus, our group has focused on identifying inhibitors of HBsAg secretion. By using the HBV-expressing cell line HepG2.2.15, high-throughput screening of an 80,288-compound synthetic small-molecule library identified HBF-0259, an aromatically substituted tetrahydro-tetrazolo-(1, 5-a)-pyrimidine. Following resynthesis, HBF-0259 had a 50% effective concentration of approximately 1.5 microM in a secondary, HBV-expressing cell line, with a concentration that exhibited 50% cytotoxicity of >50 microM. The equilibrium concentration of HBF-0259 in aqueous solution at physiological pH was 15 to 16 microM; the selective index was thus >9. As intended by our screening paradigm, HBF-0259 is a selective, potent inhibitor of secretion of both subviral and DNA-containing viral particles, while the secretion of alpha-1-acid glycoprotein and alpha-1-antitrypsin was unaffected. The HBV e antigen, which is not a constituent of HBV particles, was also unaffected, suggesting that the secretion of particles bearing HBV structural glycoproteins is targeted directly. Inhibitory activity was also confirmed by transfection of HBsAg, indicating that the action of the compound is independent of those of other viral proteins. HBF-0259 had no effect on HBV DNA synthesis, demonstrating that inhibition is independent of viral genomic replication. Finally, HBF-0259 had little or no effect on the cell-to-cell spread of two unrelated viruses, suggesting that it is a specific inhibitor of secretion of HBsAg. Possible mechanisms of action and the implications for its development are discussed.     

The use of 5% mafenide acetate solution in the postgraft treatment of necrotizing fasciitis

Twenty-nine patients with necrotizing fasciitis who were treated with 5% mafenide acetate solution (MAS) as an adjunct after grafting were compared with 45 patients treated without MAS. Statistical analysis of differences was obtained through P values by chi2 testing. The MAS+ (M) and MAS- (C) groups were similar in percent skin deficit (M = 7.5%; C = 9.8%), with the extremity being the most common area of infection. Streptococcus was the most common single organism but polymicrobial infections were the most prevalent (M = 48%; C = 58%). Patients with necrotizing fasciitis treated with MAS had fewer debridements per patient (M = 3.7; C = 5.4), fewer closure procedures (average per patient: M = 1.2; C = 1.73) and a higher percent of first-time closures (83 vs 59%; chi2 = 4.26; P = 0.039). There is a trend toward a lower mortality rate (3.4 vs 13%; chi2 = 2.00; P = 0.158). We conclude that MAS is a useful adjunct in necrotizing fasciitis wound care protocols.     

间充质干细胞的来源

目的:间充质干细胞具有强大的增殖能力和多向分化潜能,文章对其主要的来源途径予以综述。资料来源:应用计算机检索Medline1991-01/2006-01期间的相关文章,检索词为“mesenchyma stem cells,origin,research progress”,并限定文章语言种类为English。同时计算机检索中国期刊全文数据库1998-01/2006-10期间的相关文章,检索词为“间充质干细胞,来源,研究进展”,并限定文章语言种类为中文。资料选择:对资料进行初审,并查看每篇文献后的引文。纳入标准:①间充质干细胞的起源。②间充质干细胞研究进展、干细胞的分离及鉴定。排除标准:重复研究、个案报告或Meta分析类文章。资料提炼:共收集到96篇相关文献,40篇文献符合纳入标准,排除的56篇文献为内容陈旧或重复。符合纳入标准的40篇文献中,分别涉及骨髓、肌肉、脐血、胎盘、外周血、脂肪组织、血管及其他来源的间充质干细胞。资料综合:间充质干细胞是属于中胚层的一类多能干细胞,具有强大的增殖能力和多向分化潜能,动物模型试验和临床应用研究也取得了一定的效果。间充质干细胞来源广泛,易于获得,临床上为神经损伤及其他系统的损伤修复提供了更为广泛的途径。结论:间充质干细胞主要来源于骨髓、肌肉、脐血、外周血、胎盘等组织,具有广阔的应用前景。     

Involvement of a change in penicillin target and peptidoglycan structure in low-level resistance to beta-lactam antibiotics in Neisseria gonorrhoeae.

A penicillin-susceptible gonococcus and its low-level resistant penA transformant were examined with regard to their penicillin-binding proteins (PBPs) and their peptidoglycan structures. Treatment of the susceptible strain with its MIC of penicillin (0.01 microgram/ml) led to significant binding to PBPs 2 and 3 and a substantial decrease in the O-acetyl modification on the peptidoglycan. Peptidoglycan synthesis gradually ceased over an extended time. When the penA strain was treated with the same concentration of penicillin, only binding to PBP 3 was observed and there was no O-acetylation decrease, with continued peptidoglycan synthesis. This suggested that PBP 2 was the primary target in penicillin-susceptible gonococci and that this protein participated in the O-acetylation of peptidoglycan. Penicillin concentrations representing the MIC for the penA transformant (0.06 microgram/ml) caused significant binding to PBPs 1, 2, and 3 in the susceptible strain and PBPs 1 and 3 in the penA strain. In both strains the rate of peptidoglycan synthesis and the cross-linkage of the peptidoglycan made declined sharply, suggesting that significant inhibition of PBP 1 interfered with transpeptidation. A model for low-level resistance is proposed in which a decreased PBP 2 affinity leads to assumption of the role of primary target in the resistant transformant by PBP 1. The differences observed in peptidoglycan metabolism are a direct consequence of this change.     

Gray matter volumes in obsessive-compulsive disorder before and after fluoxetine or cognitive-behavior therapy: a randomized clinical trial

Serotonin reuptake inhibitors and cognitive-behavior therapy (CBT) are considered first-line treatments for obsessive-compulsive disorder (OCD). However, little is known about their modulatory effects on regional brain morphology in OCD patients. We sought to document structural brain abnormalities in treatment-naive OCD patients and to determine the effects of pharmacological and cognitive-behavioral treatments on regional brain volumes. Treatment-naive patients with OCD (n=38) underwent structural magnetic resonance imaging scan before and after a 12-week randomized clinical trial with either fluoxetine or group CBT. Matched-healthy controls (n=36) were also scanned at baseline. Voxel-based morphometry was used to compare regional gray matter (GM) volumes of regions of interest (ROIs) placed in the orbitofrontal, anterior cingulate and temporolimbic cortices, striatum, and thalamus. Treatment-naive OCD patients presented smaller GM volume in the left putamen, bilateral medial orbitofrontal, and left anterior cingulate cortices than did controls (p<0.05, corrected for multiple comparisons). After treatment with either fluoxetine or CBT (n=26), GM volume abnormalities in the left putamen were no longer detectable relative to controls. ROI-based within-group comparisons revealed that GM volume in the left putamen significantly increased (p<0.012) in fluoxetine-treated patients (n=13), whereas no significant GM volume changes were observed in CBT-treated patients (n=13). This study supports the involvement of orbitofronto/cingulo-striatal loops in the pathophysiology of OCD and suggests that fluoxetine and CBT may have distinct neurobiological mechanisms of action.     

Wireless peripheral nerve stimulation increases pain threshold in two neuropathic rat models

Neurostimulation approaches including spinal cord and peripheral nerve stimulation are typically used to treat intractable chronic pain in individuals who are refractory to pain medications. Our earlier studies have shown that a voltage controlled capacitive discharge (VCCD) method of stimulation of nerve activation is able to selectively recruit activity in large myelinated nerve fibers. In this study, we were able to wirelessly activate the sciatic nerve using the VCCD waveform. The purpose of this study was to determine whether this waveform can effectively improve two of the most troublesome pain symptoms experienced by patients with chronic neuropathic pain mechanical and cold hyperalgesia. Neuropathic mechanical hyperalgesia was reproduced using the Spinal Nerve Ligation (SNL) rat model whereas cold allodynia was reproduced using the Chronic Constriction Injury (CCI) model in male rats. Von Frey and cold plate tests were used to evaluate paw withdrawal threshold and latency to withdrawal before and after stimulation in experimental and control rats. Paw withdrawal threshold increased significantly compared to post-lesion baseline after VCCD stimulation in SNL rats. We also observed a significant improvement in cold allodynia in the active implant CCI rats after stimulation. These results suggest that the VCCD stimulation using a wireless microstimulator may be effective in the treatment of neuropathic pain.