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1.  Discrepancies between HIV prevention communication attitudes and actual conversations about HIV testing within social and sexual networks of African American men who have sex with men 
Sexually transmitted diseases  2014;41(4):221-226.
Promoting communication among African American men who have sex with men (AA MSM) and their social networks about HIV testing is an avenue for altering HIV prevention social norms. This study examined attitudes of AA MSM on talking with peers about HIV testing and characteristics of their network members with whom they have these conversations.
Data came from a cross-sectional survey of n=226 AA MSM who were aged >=18 years and self-reported sex with another male in the prior 90 days. Participants completed an inventory to characterize network members with whom they had conversations about HIV testing and HIV status.
The majority of the sample reported that it was important/very important to talk to male friends about HIV (85%) and that they were comfortable/very comfortable talking with their friends about sexual behaviors (84%). However, a small proportion of the social network had been talked to by the participant about HIV testing (14%). Among sexual networks, 58% had been talked to about their HIV status and this was positively associated with main and casual partner type compared to partners with whom money or drugs were exchanged.
Findings suggest that positive attitudes about communication may be necessary but not sufficient for actual conversations to occur. Designing interventions that increase communication with social networks is warranted.
PMCID: PMC4516456  PMID: 24622631
MSM; social networks; communication; HIV testing
2.  An examination of associations between social norms and risky alcohol use among African American men who have sex with men 
Drug and alcohol dependence  2013;134:218-221.
Research has indicated associations between risky alcohol consumption and sexual risk behavior, which may in turn present risk of HIV acquisition or transmission. Little is known about social determinants of problematic alcohol use among African American MSM (AA MSM), a risk group disproportionately affected by HIV. The present study sought to explore associations between risky alcohol use and perceived peer norms of alcohol use among a sample of urban African American men who have sex with men (AA MSM).
A cross-sectional survey was administered to 142 AA MSM in Baltimore, Maryland, recruited using active and passive methods. Risky and hazardous alcohol use was assessed using the Alcohol Use Disorders Identification Test (AUDIT) and participants self-reported descriptive and injunctive peer norms regarding frequency and quantity of alcohol consumption.
Nearly half reported hazardous or high risk consumption of alcohol. Perceived peer alcohol norms, both descriptive and injunctive, were associated with alcohol use, including hazardous use.
The findings highlight the role of social factors on problematic alcohol use among AA MSM. Results indicate that AA MSM's use of alcohol is associated with their perceptions of peer alcohol use. Potential interventions could include norms-based campaigns that seek to reduce risky alcohol consumption among AA MSM as well as programs to screen and identify individuals with problematic alcohol use.
PMCID: PMC4499778  PMID: 24210770
African American men who have sex with men; social norms; alcohol use; AUDIT
3.  HIV, syphilis, hepatitis C and risk behaviours among commercial sex male clients in Sichuan province, China 
Sexually transmitted infections  2010;86(7):559-564.
Commercial sex male clients (CSMC) are at risk of sexually transmitted infections (STI) including HIV. This study reports the prevalence of HIV, syphilis and hepatitis C virus (HCV), a history of STI and HIV-related risk behaviours in a sample of 600 CSMC in three urban areas in Sichuan province, China. The risk factors for prevalent syphilis infection are also examined.
A cross-sectional survey was conducted with 600 CSMC in Sichuan province, China. Finger stick blood samples were collected for HIV, syphilis and HCV tests. Risk factors for syphilis were assessed using multivariate logistic regression by accounting for variance within and between study sites.
Western blot confirmatory test results indicated that HIV prevalence was 1.5% (n=9). 32 participants (5.3%) screened positive for syphilis and 52 (8.7%) positive for HCV. The overall prevalence of consistent condom use with female sex workers (FSW) was 30.5%. Multivariate logistic regression analyses revealed local household registration (AOR 0.35, 95% CI 0.25 to 0.50), having snorted heroin in the past 6 months (AOR 2.36, 95% CI 1.18 to 4.74), always washing genitals after having sex with FSW (AOR 3.04, 95% CI 1.10 to 9.12) and consistent condom use with FSW (AOR 0.67, 95% CI 0.46 to 0.98) were significant correlates of syphilis infection.
There is a large burden of syphilis infection coupled with high-risk sexual and substance use behaviours among male clients in Sichuan province, China. The data suggest that effective and comprehensive prevention interventions to promote condom use and reduce substance use among male clients in Sichuan province are urgently needed.
PMCID: PMC4487621  PMID: 20826867
4.  A qualitative study on commercial sex behaviors among male clients in Sichuan Province, China 
AIDS care  2010;22(2):246-252.
Males who seek commercial sex have been identified as an important “bridging population” in the transmission of HIV. There is little information on the HIV-related risk perceptions and behaviors among commercial sex male clients (CSMCs) in China. This study reports qualitative findings from six focus groups and 41 in-depth interviews with CSMCs in Sichuan Province, China. Commercial sex visits were described as a group activity and associated with patterns of social-network specific interactions and norms. Primary motivations for visiting female sex workers included peer pressure, stress reduction, and fulfilling a need for an intimate and emotional support. Male clients’ decisions about condom use were influenced by their perceived norms of condom use, susceptibility of HIV infection, and the condom policy and availability in the establishments. Implications of these findings for further research and interventions are discussed.
PMCID: PMC4487632  PMID: 20390503
commercial sex; male clients; China; HIV; qualitative; social norms
5.  Equilibrative Nucleoside Transporters 1 and 4: Which One Is a Better Target for Cardioprotection Against Ischemia–Reperfusion Injury? 
The cardioprotective effects of adenosine and adenosine receptor agonists have been studied extensively. However, their therapeutic outcomes in ischemic heart disease are limited by systemic side effects such as hypotension, bradycardia, and sedation. Equilibrative nucleoside transporter (ENT) inhibitors may be an alternative. By reducing the uptake of extracellular adenosine, ENT1 inhibitors potentiate the cardioprotective effect of endogenous adenosine. They have fewer systemic side effects because they selectively increase the extracellular adenosine levels in ischemic tissues undergoing accelerated adenosine formation. Nonetheless, long-term inhibition of ENT1 may adversely affect tissues that have low capacity for de novo nucleotide biosynthesis. ENT1 inhibitors may also affect the cellular transport, and hence the efficacy, of anticancer and antiviral nucleoside analogs used in chemotherapy. It has been proposed that ENT4 may also contribute to the regulation of extracellular adenosine in the heart, especially under the acidotic conditions associated with ischemia. Like ENT1 inhibitors, ENT4 inhibitors should work specifically on ischemic tissues. Theoretically, ENT4 inhibitors do not affect tissues that rely on ENT1 for de novo nucleotide synthesis. They also have no interaction with anticancer and antiviral nucleosides. Development of specific ENT4 inhibitors may open a new avenue in research on ischemic heart disease therapy.
PMCID: PMC4461397  PMID: 26070128
nucleoside transporters; adenosine; cardioprotection; ischemia
6.  Ginsenoside-Rb1 Protects Hypoxic- and Ischemic-Damaged Cardiomyocytes by Regulating Expression of miRNAs 
Ginsenoside (GS-Rb1) is one of the most important active compounds of ginseng, with extensive evidence of its cardioprotective properties. However, the miRNA mediated mechanism of GS-Rb1 on cardiomyocytes remains unclear. Here, the roles of miRNAs in cardioprotective activity of GS-Rb1 were investigated in hypoxic- and ischemic-damaged cardiomyocytes. Neonatal rat cardiomyocytes (NRCMs) were first isolated, cultured, and then incubated with or without GS-Rb1 (2.5–40 μM) in vitro under conditions of hypoxia and ischemia. Cell growth, proliferation, and apoptosis were detected by MTT and flow cytometry. Expressions of various microRNAs were analyzed by real-time PCR. Compared with that of the control group, GS-Rb1 significantly decreased cell death in a dose-dependent manner and expressions of mir-1, mir-29a, and mir-208 obviously increased in the experimental model groups. In contrast, expressions of mir-21 and mir-320 were significantly downregulated and GS-Rb1 could reverse the differences in a certain extent. The miRNAs might be involved in the protective effect of GS-Rb1 on the hypoxia/ischemia injuries in cardiomyocytes. The effect might be based on the upregulation of mir-1, mir-29a, and mir-208 and downregulation of mir-21 and mir-320. This might provide us a new target to explore the novel strategy for ischemic cardioprotection.
PMCID: PMC4449925  PMID: 26074986
7.  Relaxation Effect of Abacavir on Rat Basilar Arteries 
PLoS ONE  2015;10(4):e0123043.
The use of abacavir has been linked with increased cardiovascular risk in patients with human immunodeficiency virus infection; however, the mechanism involved remains unclear. We hypothesize that abacavir may impair endothelial function. In addition, based on the structural similarity between abacavir and adenosine, we propose that abacavir may affect vascular contractility through endogenous adenosine release or adenosine receptors in blood vessels.
The relaxation effect of abacavir on rat basilar arteries was studied using the myograph technique. Cyclic GMP and AMP levels were measured by immunoassay. The effects of abacavir on nucleoside transporters were studied using radiolabeled nucleoside uptake experiments. Ecto-5′ nucleotidase activity was determined by measuring the generation of inorganic phosphate using adenosine monophosphate as the substrate.
Abacavir induced the relaxation of rat basilar arteries in a concentration-dependent manner. This relaxation was abolished when endothelium was removed. In addition, the relaxation was diminished by the nitric oxide synthase inhibitor, L-NAME, the guanylyl cyclase inhibitor, ODQ, and the protein kinase G inhibitor, KT5820. Abacavir also increased the cGMP level in rat basilar arteries. Abacavir-induced relaxation was also abolished by adenosine A2 receptor blockers. However, abacavir had no effect on ecto-5’ nucleotidase and nucleoside transporters. Short-term and long-term treatment of abacavir did not affect acetylcholine-induced relaxation in rat basilar arteries.
Abacavir induces acute endothelium-dependent relaxation of rat basilar arteries, probably through the activation of adenosine A2 receptors in endothelial cells, which subsequently leads to the release of nitric oxide, resulting in activation of the cyclic guanosine monophosphate/protein kinase G-dependent pathway in vascular smooth muscle cells. It is speculated that abacavir-induced cardiovascular risk may not be related to endothelial dysfunction as abacavir does not impair relaxation of blood vessels. The most likely explanation of increased cardiovascular risk may be increased platelet aggregation as suggested by other studies.
PMCID: PMC4390379  PMID: 25853881
8.  Age and Dark Rearing Bidirectionally Regulate the Level and Laminar Pattern of Expression of Abelson Interacting Protein 2 (Abi-2), a Novel Candidate Visual Cortical Plasticity Gene 
Electrophysiological studies indicate that cat visual cortical critical period neuronal plasticity peaks around 5 weeks and largely disappears by 20 weeks. Dark rearing slows this time course. Normal cats are more plastic than dark reared cats at 5 weeks but the opposite is true at 20 weeks. Thus, a stringent criterion for identifying genes controlling neuronal plasticity is that normal and dark rearing produce opposite direction differences in expression between young and older animals. Differential display PCR identified Abelson interacting protein 2 (Abi-2) as a candidate plasticity gene regulated according to this criterion. Western blotting showed bidirectional regulation of Abi-2 protein levels in cats and mice that was specific to visual cortex and did not occur in frontal cortex. Immunohistochemistry indicated developmental changes in Abi-2 laminar expression in cat visual cortex. Dark rearing altered laminar expression such that at 5 weeks dark reared cats were similar to 1 week normally reared cats and at 20 weeks, dark reared cats were similar to 5–10 week normally reared animals. The effect of dark rearing on both Abi-2 expression levels and laminar expression patterns was to slow the normal developmental process, the same effect seen on physiologically assessed plasticity in visual cortex.
PMCID: PMC3797860  PMID: 23828391
Visual Deprivation; Visual Development; differential display PCR; Neuronal Plasticity
9.  Injection Drug Users’ Involvement In Drug Economy: Dynamics of Sociometric and Egocentric Social Networks 
Connections (Toronto, Ont.)  2013;33(1):24-34.
The purpose of this analysis was to examine the effect of social network cohesiveness on drug economy involvement, and to test whether this relationship is mediated by drug support network size in a sample of active injection drug users. Involvement in the drug economy was defined by self-report of participation in at least one of the following activities: selling drugs, holding drugs or money for drugs, providing street security for drug sellers, cutting/packaging/cooking drugs, selling or renting drug paraphernalia (e.g., pipes, tools, rigs), and injecting drugs in others’ veins. The sample consists of 273 active injection drug users in Baltimore, Maryland who reported having injected drugs in the last 6 months and were recruited through either street outreach or by their network members. Egocentric drug support networks were assessed through a social network inventory at baseline. Sociometric networks were built upon the linkages by selected matching characteristics, and k-plex rank was used to characterize the level of cohesiveness of the individual to others in the social network. Although no direct effect was observed, structural equation modeling indicated k-plex rank was indirectly associated with drug economy involvement through drug support network size. These findings suggest the effects of large-scale sociometric networks on injectors’ drug economy involvement may occur through their immediate egocentric networks. Future harm reduction programs for injection drug users (IDUs) should consider providing programs coupled with economic opportunities to those drug users within a cohesive network subgroup. Moreover, individuals with a high connectivity to others in their network may be optimal individuals to train for diffusing HIV prevention messages.
PMCID: PMC4193503  PMID: 25309015
10.  Maintenance of Large Numbers of Virus Genomes in Human Cytomegalovirus-Infected T98G Glioblastoma Cells 
Journal of Virology  2014;88(7):3861-3873.
After infection, human cytomegalovirus (HCMV) persists for life. Primary infections and reactivation of latent virus can both result in congenital infection, a leading cause of central nervous system birth defects. We previously reported long-term HCMV infection in the T98G glioblastoma cell line (1). HCMV infection has been further characterized in T98Gs, emphasizing the presence of HCMV DNA over an extended time frame. T98Gs were infected with either HCMV Towne or AD169-IE2-enhanced green fluorescent protein (eGFP) strains. Towne infections yielded mixed IE1 antigen-positive and -negative (Ag+/Ag−) populations. AD169-IE2-eGFP infections also yielded mixed populations, which were sorted to obtain an IE2− (Ag−) population. Viral gene expression over the course of infection was determined by immunofluorescent analysis (IFA) and reverse transcription-PCR (RT-PCR). The presence of HCMV genomes was determined by PCR, nested PCR (n-PCR), and fluorescence in situ hybridization (FISH). Compared to the HCMV latency model, THP-1, Towne-infected T98Gs expressed IE1 and latency-associated transcripts for longer periods, contained many more HCMV genomes during early passages, and carried genomes for a greatly extended period of passaging. Large numbers of HCMV genomes were also found in purified Ag− AD169-infected cells for the first several passages. Interestingly, latency transcripts were observed from very early times in the Towne-infected cells, even when IE1 was expressed at low levels. Although AD169-infected Ag− cells expressed no detectable levels of either IE1 or latency transcripts, they also maintained large numbers of genomes within the cell nuclei for several passages. These results identify HCMV-infected T98Gs as an attractive new model in the study of the long-term maintenance of virus genomes in the context of neural cell types.
IMPORTANCE Our previous work showed that T98G glioblastoma cells were semipermissive to HCMV infection; virus trafficked to the nucleus, and yet only a proportion of cells stained positive for viral antigens, thus allowing continual subculturing and passaging. The cells eventually transitioned to a state where viral genomes were maintained without viral antigen expression or virion production. Here we report that during long-term T98G infection, large numbers of genomes were maintained within all of the cells' nuclei for the first several passages (through passage 4 [P4]), even in the presence of continual cellular division. Surprisingly, genomes were maintained, albeit at a lower level, through day 41. This is decidedly longer than in any other latency model system that has been described to date. We believe that this system offers a useful model to aid in unraveling the cellular components involved in viral genome maintenance (and presumably replication) in cells carrying long-term latent genomes in a neural context.
PMCID: PMC3993548  PMID: 24453365
11.  MAE-FMD: Multi-agent evolutionary method for functional module detection in protein-protein interaction networks 
BMC Bioinformatics  2014;15(1):325.
Studies of functional modules in a Protein-Protein Interaction (PPI) network contribute greatly to the understanding of biological mechanisms. With the development of computing science, computational approaches have played an important role in detecting functional modules.
We present a new approach using multi-agent evolution for detection of functional modules in PPI networks. The proposed approach consists of two stages: the solution construction for agents in a population and the evolutionary process of computational agents in a lattice environment, where each agent corresponds to a candidate solution to the detection problem of functional modules in a PPI network. First, the approach utilizes a connection-based encoding scheme to model an agent, and employs a random-walk behavior merged topological characteristics with functional information to construct a solution. Next, it applies several evolutionary operators, i.e., competition, crossover, and mutation, to realize information exchange among agents as well as solution evolution. Systematic experiments have been conducted on three benchmark testing sets of yeast networks. Experimental results show that the approach is more effective compared to several other existing algorithms.
The algorithm has the characteristics of outstanding recall, F-measure, sensitivity and accuracy while keeping other competitive performances, so it can be applied to the biological study which requires high accuracy.
PMCID: PMC4262229  PMID: 25265982
Computational biology; Protein-protein interaction network; Functional module detection; Multi-agent evolution
12.  Ligusticum wallichii Extract Inhibited the Expression of IL-1β after AMI in Rats 
This study investigated the effects of Ligusticum wallichii on IL-1β expression in myocardium and central nervous system after AMI. AMI rat was administrated with Ligusticum wallichii extract. A series of assays were used to detect the effects of Ligusticum wallichii extract on infarct size, left ventricular ejection fraction, expression of TLR-4, NF-κB, and IL-1β in myocardium, IL-1β expression in serum and hypothalamus, and NPY expression in hypothalamus. We observed that Ligusticum wallichii extract improved the left ventricular ejection fraction and reduced infarct area enlargement after AMI, by inhibiting the expression of IL-1β in myocardium, serum, and hypothalamus. Ligusticum wallichii extract reduced the expression of IL-1β in myocardium by regulating TLR4-NF-κB signaling pathway and inhibited IL-1β in hypothalamus by regulating NPY mRNA expression.
PMCID: PMC4150451  PMID: 25202335
13.  Ginsenoside Rb1 Protects Neonatal Rat Cardiomyocytes from Hypoxia/Ischemia Induced Apoptosis and Inhibits Activation of the Mitochondrial Apoptotic Pathway 
Aim. To investigate the effect of Ginsenoside Rb1 (GS-Rb1) on hypoxia/ischemia (H/I) injury in cardiomyocytes in vitro and the mitochondrial apoptotic pathway mediated mechanism. Methods. Neonatal rat cardiomyocytes (NRCMs) for the H/I groups were kept in DMEM without glucose and serum, and were placed into a hypoxic jar for 24 h. GS-Rb1 at concentrations from 2.5 to 40 µM was given during hypoxic period for 24 h. NRCMs injury was determined by MTT and lactate dehydrogenase (LDH) leakage assay. Cell apoptosis, ROS accumulation, and mitochondrial membrane potential (MMP) were assessed by flow cytometry. Cytosolic translocation of mitochondrial cytochrome c and Bcl-2 family proteins were determined by Western blot. Caspase-3 and caspase-9 activities were determined by the assay kit. Results. GS-Rb1 significantly reduced cell death and LDH leakage induced by H/I. It also reduced H/I induced NRCMs apoptosis induced by H/I, in accordance with a minimal reactive oxygen species (ROS) burst. Moreover, GS-Rb1 markedly decreased the translocation of cytochrome c from the mitochondria to the cytosol, increased the Bcl-2/ Bax ratio, and preserved mitochondrial transmembrane potential (ΔΨm). Its administration also inhibited activities of caspase-9 and caspase-3. Conclusion. Administration of GS-Rb1 during H/I in vitro is involved in cardioprotection by inhibiting apoptosis, which may be due to inhibition of the mitochondrial apoptotic pathway.
PMCID: PMC4120487  PMID: 25120573
14.  “Drinking buddies” and alcohol dependence symptoms among African American men and women in Baltimore, MD 
Drug and alcohol dependence  2012;128(0):123-129.
Social network characteristics have been found to be associated with a variety of risky behaviors, including alcohol consumption. This study assessed the relationships between the characteristics of drinking buddies and alcohol dependence symptoms among a sample of African American men and women.
This is a cross-sectional study using baseline data from 721 impoverished African American men and women participating in an HIV prevention study in Baltimore, MD. Alcohol dependence symptoms were assessed through the Alcohol Use Disorders Identification Test (AUDIT) and was defined as AUDIT score>=13 for females and AUDIT score>=15 for males. Logistic regression models with generalized estimating equations (GEE) using network member as the unit of analysis were conducted to assess the associations between the gender or relationship (i.e,, kin, non-kin or sex partner) of the drinking buddies and the participants’ alcohol dependence symptoms.
Approximately 22% of the participants had alcohol dependence symptoms. Among male participants, alcohol dependence symptoms were associated with having drinking buddies who were sex partners (AOR: 2.41, 95%CI: 1.32, 4.39) or who were female (AOR: 2.29, 95%CI: 1.29, 4.05). Among female participants, association between the presence of drinking buddy and alcohol dependence symptoms did not depend on the types of relationship or the gender of the drinking buddy.
Social network characteristics with respect to alcohol dependence symptoms vary according to the type of relationship or the gender of the drinking buddies, especially among men. Gender-specific norm-based interventions may be a useful strategy to decrease drink problems.
PMCID: PMC4019971  PMID: 22999417
Alcohol dependence symptoms; African American; social networks; drinking buddy
15.  Factors associated with drinking alcohol before visiting female sex workers among men in Sichuan Province, China 
AIDS and behavior  2013;17(2):568-573.
Alcohol use in commercial sex is highly prevalent globally and alcohol use in conjunction with sexual activity might increase the probability of risky behaviors, and. In the current study, we explored individual and contextual factors associated with drinking alcohol before visiting female sex workers (FSWs) among 560 male clients in Sichuan province, China. A cross-sectional survey was conducted in Sichuan province, China. Over one-fifth (21.1%) of the participants reported always using alcohol before having sex with FSWs. As compared to those who reported not always drinking alcohol before having sex with FSWs, male clients who reported always drinking alcohol before having sex with FSWs had higher income, were more likely to have main sex partners, to drink alcohol daily, to report minor depressive symptoms and were more likely to visit FSWs with friends rather than by themselves. Results from this study highlight the importance of addressing alcohol use among men who pay for sex in China. Future interventions should promote alcohol-related norms in reducing the harms associated with consuming alcohol.
PMCID: PMC4017933  PMID: 22806054
alcohol use; risky sexual behaviors; commercial sex; HIV; China
16.  Significance of Ubiquitin Carboxy-Terminal Hydrolase L1 Elevations in Athletes after Sub-Concussive Head Hits 
PLoS ONE  2014;9(5):e96296.
The impact of sub-concussive head hits (sub-CHIs) has been recently investigated in American football players, a population at risk for varying degrees of post-traumatic sequelae. Results show how sub-CHIs in athletes translate in serum as the appearance of reporters of blood-brain barrier disruption (BBBD), how the number and severity of sub-CHIs correlate with elevations of putative markers of brain injury is unknown. Serum brain injury markers such as UCH-L1 depend on BBBD. We investigated the effects of sub-CHIs in collegiate football players on markers of BBBD, markers of cerebrospinal fluid leakage (serum beta 2-transferrin) and markers of brain damage. Emergency room patients admitted for a clinically-diagnosed mild traumatic brain injury (mTBI) were used as positive controls. Healthy volunteers were used as negative controls. Specifically this study was designed to determine the use of UCH-L1 as an aid in the diagnosis of sub-concussive head injury in athletes. The extent and intensity of head impacts and serum values of S100B, UCH-L1, and beta-2 transferrin were measured pre- and post-game from 15 college football players who did not experience a concussion after a game. S100B was elevated in players experiencing the most sub-CHIs; UCH-L1 levels were also elevated but did not correlate with S100B or sub-CHIs. Beta-2 transferrin levels remained unchanged. No correlation between UCH-L1 levels and mTBI were measured in patients. Low levels of S100B were able to rule out mTBI and high S100B levels correlated with TBI severity. UCH-L1 did not display any interpretable change in football players or in individuals with mild TBI. The significance of UCH-L1 changes in sub-concussions or mTBI needs to be further elucidated.
PMCID: PMC4012998  PMID: 24806476
Journal of community psychology  2013;41(4):10.1002/jcop.21548.
Men who have sex with men (MSM) experience greater mental health problems as compared with heterosexual populations. Informal social support plays a critical role in emotional well-being. The primary goal of this article is to examine the relationship between depressive symptoms and received social support from family, friends, and sex partners within the social network from a sample of 188 African American MSM in Baltimore, Maryland. We found that receiving emotional support from a family member or a sex partner was associated with reduced odds of having depressive symptoms. Receiving financial support from a family member or a friend was associated with increased odds of having depressive symptoms. The results suggest the importance of emotional support provided by family and sex partner in mental health and the potential value of training African American MSM in skills to enhance the quality of the relationships.
PMCID: PMC3736997  PMID: 23935226
18.  Genetic Analysis of Diversity within a Chinese Local Sugarcane Germplasm Based on Start Codon Targeted Polymorphism 
BioMed Research International  2014;2014:468375.
In-depth information on sugarcane germplasm is the basis for its conservation and utilization. Data on sugarcane molecular markers are limited for the Chinese sugarcane germplasm collections. In the present study, 20 start codon targeted (SCoT) marker primers were designed to assess the genetic diversity among 107 sugarcane accessions within a local sugarcane germplasm collection. These primers amplified 176 DNA fragments, of which 163 were polymorphic (92.85%). Polymorphic information content (PIC) values ranged from 0.783 to 0.907 with a mean of 0.861. Unweighted pair group method of arithmetic averages (UPGMA) cluster analysis of the SCoT marker data divided the 107 sugarcane accessions into six clusters at 0.674 genetic similarity coefficient level. Relatively abundant genetic diversity was observed among ROC22, ROC16, and ROC10, which occupied about 80% of the total sugarcane acreage in China, indicating their potential breeding value on Mainland China. Principal component analysis (PCA) partitioned the 107 sugarcane accessions into two major groups, the Domestic Group and the Foreign Introduction Group. Each group was further divided based on institutions, where the sugarcane accessions were originally developed. The knowledge of genetic diversity among the local sugarcane germplasm provided foundation data for managing sugarcane germplasm, including construction of a core collection and regional variety distribution and subrogation.
PMCID: PMC3980922  PMID: 24779012
19.  Acute toxicity of nickel nanoparticles in rats after intravenous injection 
This study was carried out to add scientific data in regard to the use of metallic nanoparticles in nanomedicine. The acute toxicity of nickel (Ni) nanoparticles (50 nm), intravenously injected through the dorsal penile vein of Sprague Dawley rats was evaluated in this study. Fourteen days after injection, Ni nanoparticles induced liver and spleen injury, lung inflammation, and caused cardiac toxicity. These results indicate that precautionary measures should be taken with regard to the use of Ni nanoparticles or Ni compounds in nanomedicine.
PMCID: PMC3958504  PMID: 24648736
nickel; nanoparticles; intravenous; acute toxicity
20.  Injection drug users' and their risk networks experiences of and attitudes toward drug dealer violence in Baltimore, Maryland 
A large portion of violence associated with drug use is due to drug dealing. These analyses sought to examine injection drug users' attitudes and experiences of drug dealer violence.
The current study used the 18-month follow up data of STEP into Action (STEP) study, an HIV prevention intervention among drug injectors and their risk network members conducted in Baltimore, Maryland. Four scales assessed acceptability of drug dealer violence, willingness to talk to drug users about avoiding drug dealer violence, social norms about reporting drug dealer violence, and intentions to report drug dealer violence to the police.
Many (44%) of the 373 participants reported witnessing drug dealers' acts of violence within the prior 6 months. Although the majority of participants disagreed with statements on the acceptability of dealers using violence, only a minority indicated that they would call the police if they observed dealer violence. Most participants indicated that they would be interested in talking to drug users about how to avoid violent dealers. Males were more likely to report that violence was acceptable, whereas African Americans were less likely to condone violence. Those who were homeless and had higher incomes were more likely to report witnessing drug dealer violence.
These results suggest that it may be feasible to train current and former drug users and their risk network members in methods to promote violence reduction among drug dealers.
PMCID: PMC3519954  PMID: 22959117
violence; drug dealer; injection drug users
21.  Syndemics of syphilis, HCV infection, and methamphetamine use along the east coast of China 
BMC Public Health  2014;14:172.
An upsurge in club drug use has been observed in recent years in some cities of China, especially methamphetamine, which is quickly replacing heroin to become the most widespread drug across the nation. This study investigated the type of drugs used, syphilis and hepatitis C virus (HCV) infection and the correlates for syphilis, HCV and unprotected commercial sex behavior among drug users in two cities along the east coast of China.
A cross-sectional survey conducted in 2010 provided demographics, sexual and drug use behaviors, HIV knowledge and the utilization of intervention services among drug users. Blood samples were tested for HIV, syphilis, and HCV infection.
Of 805 eligible participants, 0.2% were infected with HIV, 3.7% with HCV, and 9.6% with syphilis. Of the participants, 96.6% were methamphetamine users, 11.9% reported ever having used ≥2 types of these drugs, and 11.4% reported ever injecting drugs. In the multivariable logistic regression analysis, participants infected with syphilis were more likely to be female (adjusted odds ratio (AOR)=2.8, 95% confidence interval (CI): 1.2-6.5), have ever had commercial sex in the past 12 months (AOR=2.0, 95% CI: 1.0-3.9), be infected with HCV (AOR=12.1, 95% CI: 4.1-20.3) and less likely to have ever had sex with regular partners in the past 12 months (AOR=0.2, 95% CI: 0.1-0.6). Participants infected with HCV were more likely to have ever injected drugs (AOR=2.7, 95% CI: 1.1-6.5) and be infected with syphilis (AOR=8.0, 95% CI: 3.5-18.0). Participants who had unprotected sex with commercial sex partners in the last sexual encounter were more likely to be female (AOR=2.9, 95% CI:1.7-4.9), have middle school or lower level education (AOR=3.4, 95% CI:2.0-5.5), never have received intervention in the last year (AOR=2.1, 95%CI:1.2-3.6) and be infected with syphilis (AOR=4.2, 95% CI:2.4-7.4).
Methamphetamine is the predominant drug used among the drug users, the prevalence of syphilis and HCV infection are alarmingly high, and unprotected commercial sex was common among this group. The findings highlight the need for effective, multifaceted interventions addressing sexual and drug use-related risky behaviors among this group. Further research is needed to better understand the causal pathway of the syndemics.
PMCID: PMC3936988  PMID: 24533587
Syphilis; HCV; Methamphetamine; Sexual behavior; Drug user
22.  The epidemiology of finding a dead body: reports from inner-city Baltimore, Maryland US 
Community mental health journal  2013;49(1):106-109.
In the US, there are no national statistics on encountering a dead body, which can be viewed as a measure of community health and a stressful life event. Participants for an HIV prevention intervention targeting drug users were recruited in areas of inner-city Baltimore, Maryland .Nine hundred and fifty one respondents, most with a history of drug use, were asked “have you ever found a dead body?” and 17.0% reported they had. Leading causes of death were: violence (37%), natural causes (22.2%), drug overdose (21.6%), accidental death (3.1%), and suicide (2.5%). In multivariate logistic models, respondents with longer history of drug use and more roles in a drug economy were more likely to be exposed to a dead body. The study results suggest that this population has a high level of experiences with mortality associated with violence and drugs. To obtain a better understanding of community health, future studies should assess not only morbidity and mortality, but also how death and illness is experienced by the community.
PMCID: PMC3406247  PMID: 22297618
Urban Health; Mortality; Drug use; Violence; Mental Health
23.  Noninvasive Assessments of Optic Nerve Neurodegeneration in Transgenic Mice With Isolated Optic Neuritis 
To determine if phosphorylated neurofilament heavy chain (pNF-H) released into the bloodstream and the pattern ERG are noninvasive indicators of neurodegeneration in experimental optic neuritis.
Serum from Myelin oligodendrocyte glycoprotein (MOG)-specific T cell receptor–positive (TCR+) transgenic mice that develop isolated optic neuritis usually without any other characteristic lesions of inflammation or demyelination in the spinal cord and littermates negative for the transgene were assayed for the presence of serum phosphorylated neurofilament H (pNF-H). In vivo measurements of optic nerve and retinal ganglion cell injury were assessed by magnetic resonance imaging (MRI), optical coherence tomography (OCT), and pattern electroretinogram (PERG). Automated two dimensional fluorescence differential in-gel electrophoresis (2D-DIGE) of pooled optic nerve samples, light, and transmission electron micrographs were used to evaluate optic atrophy postmortem.
We found an almost 3-fold elevation in serum pNF-H levels in MOG+ mice relative to MOG-littermates (P = 0.02). 2D-DIGE revealed a 3-fold reduction in optic nerve neurofilaments. Visual function assessed by the PERG was reduced by one-quarter (P = 0.033) and latencies increased by 38% (P = 0.036). MOG+ mice with the lowest PERG amplitudes had optic nerve atrophy visualized by MRI. Optic nerve diameters were reduced by one-third (P = 0.0001) and axon counts reduced by more than two-thirds. Histopathology of the spinal cords was normal.
Elevated serum pNF-H levels and the PERG are useful markers of neurodegeneration of the optic nerve in isolated experimental optic neuritis. Our findings suggest that elevations of this axonal protein in patients with optic neuritis who had a poor visual outcome are likely also due to demise of optic nerve axons.
OCT detects RNFL loss after axons die off. In this report, we show elevated serum pNF-H levels are due to isolated optic neuritis, suggesting this biomarker may be useful for selecting at initial presentation optic neuritis patients in need of neuroprotection to prevent irreversible visual loss.
PMCID: PMC3700386  PMID: 23722393
optic neuritis; neuroophthalmology; neurodegeneration; axonal degeneration; neurofilaments
24.  Cornel Iridoid Glycoside Attenuates Tau Hyperphosphorylation by Inhibition of PP2A Demethylation 
Aim. The aim of the present study was to investigate the effect of cornel iridoid glycoside (CIG) on tau hyperphosphorylation induced by wortmannin (WT) and GF-109203X (GFX) and the underlying mechanisms. Methods. Human neuroblastoma SK-N-SH cells were preincubated with CIG (50, 100, and 200 µg/ml, resp.) for 24 h and then exposed to 10 µM WT and 10 µM GFX for 3 h after washing out CIG. Immunohistochemistry was used to observe the microtubular cytoskeleton of the cultured cells. Western blotting was used to measure the phosphorylation level of tau protein, glycogen synthase kinase 3β (GSK-3β), and protein phosphatase 2A (PP2A). The activity of PP2A was detected by a biochemical assay. Results. Preincubation of CIG significantly attenuated the WT/GFX-induced tau hyperphosphorylation at the sites of Thr205, Thr212, Ser214, Thr217, Ser396, and PHF-1 and improved the damage of morphology and microtubular cytoskeleton of the cells. CIG did not prevent the decrease in p-AKT-ser473 and p-GSK-3β-ser9 induced by WT/GFX. However, CIG significantly elevated the activity of PP2A by reducing the demethylation of PP2A catalytic subunit (PP2Ac) at Leu309 and the ratio of PME-1/LCMT in the WT/GFX-treated cells. The results suggest that CIG may be beneficial to the treatment of AD.
PMCID: PMC3880719  PMID: 24454482
25.  A Pilot Study of Novel Biomarkers in Neonates With Hypoxic-Ischemic Encephalopathy 
Pediatric research  2010;68(6):10.1203/PDR.0b013e3181f85a03.
Severe hypoxic-ischemic encephalopathy (HIE) is a devastating condition that can lead to mortality and long-term disabilities in term newborns. No rapid and reliable laboratory test exists to assess the degree of neuronal injury in these patients. We propose two possible biomarkers: 1) phosphorylated axonal neurofilament heavy chain (pNF-H) protein, one of the major subunits of neurofilaments, found only in axonal cytoskeleton of neurons and 2) Ubiquitin C-terminal hydrolase 1 (UCHL1 protein) that is heavily and specifically concentrated in neuronal perikarya and dendrites. High-serum pNF-H and UCHL1 levels are reported in subarachnoid hemorrhage and traumatic brain injury, suggesting that they are released into blood following neuronal injury. We hypothesized that serum pNF-H and UCHL1 were higher in neonates with moderate-to-severe HIE than in healthy neonates. A time-limited enrollment of 14 consecutive patients with HIE and 14 healthy controls was performed. UCHL1 and pNF-H were correlated with clinical data and brain MRI. UCHL1 and pNF-H serum levels were higher in HIE versus controls. UCHL1 showed correlation with the 10-min Apgar score, and pNF-H showed correlation with abnormal brain MRI. Our findings suggest that serum UCHL1 and pNF-H could be explored as diagnostic and prognostic tools in neonatal HIE.
PMCID: PMC3851011  PMID: 20736881

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