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author:("Jin, chengqi")
1.  The Association of Self-perception of Body Fat Changes and Quality of Life in the Women’s Interagency HIV Study 
AIDS care  2013;25(12):10.1080/09540121.2013.793265.
Body fat changes are of concern to HIV-seropositive adults on highly active antiretroviral therapy (HAART). Studies examining the association of body fat changes and quality of life (QOL) in the setting of HIV infection have been conducted predominately in men. We examined the relationship of self-perceived body fat change with QOL among 1,671 HAART-using HIV-seropositive women (mean age 40 ± 8 years; 54% African American, 24% reporting ≤ 95% HAART adherence) from the Women’s Interagency HIV Study. Self-perception of any fat loss was associated with lower overall QOL. Report of any peripheral fat loss was strongly associated with nearly all QOL domains (i.e., physical functioning, role functioning, energy/fatigue, social functioning, pain, emotional well-being, health perception, and perceived health index) except cognitive functioning, whereas report of any central fat loss was significantly associated with lower social and cognitive functioning. Report of any central fat gain was associated with lower overall QOL, but only physical functioning, energy/fatigue, and cognitive functioning were significantly affected. A significant association of report of any peripheral fat gain with overall QOL was not observed, however peripheral fat gain was significantly associated with lower physical functioning and pain. We found that any report of fat loss, especially in peripheral body sites is associated with lower QOL, as was any report of central fat gain. Ultimately health providers and patients need to be informed of these associations so as to better support HIV-seropositive women who live with these effects.
PMCID: PMC3769511  PMID: 23656440
body image perception; lipoatrophy; lipohypertrophy; Quality of life; HIV-seropositive women; HAART
2.  A randomized controlled phase II trial of riluzole in early multiple sclerosis 
We evaluated the effect of riluzole versus placebo added to weekly IM interferon beta-1a in early multiple sclerosis (MS).
This is a randomized (1:1), double-blind, placebo-controlled trial of riluzole 50 mg twice daily in subjects with MS onset less than 1 year prior. Trial participation was up to 3 years. The primary endpoint was change in percent brain volume change. Secondary endpoints included changes in normalized gray and normal-appearing white matter volumes, retinal nerve fiber layer thickness (RNFL), MS Functional Composite and Symbol Digit Modalities Test scores. Mixed model regression analysis was used to compare the changes over time between groups.
Forty-three subjects were randomized to study drug (22 riluzole, 21 placebo). Baseline characteristics were overall similar between groups except for older age (P = 0.042), higher normalized cerebrospinal fluid volume (P = 0.050), lower normalized gray matter volume (P = 0.14), and thinner RNFL (P = 0.043) in the riluzole group. In the primary analysis, percent brain volume change in the placebo group decreased at a rate of 0.49% per year whereas the riluzole group decreased by 0.86% per year (0.37% more per year; 95% CI −0.78, 0.024; P = 0.065). Although age did not influence the rate of brain volume decline, the difference between groups was attenuated after adjustment for baseline normalized gray matter and lesion volume (0.26% more per year in riluzole group; 95% CI −0.057, 0.014; P = 0.22). Analyses of secondary outcomes showed no differences between groups.
This trial provides class 1 evidence that riluzole treatment does not meaningfully reduce brain atrophy progression in early MS.
PMCID: PMC4184685  PMID: 25356404
3.  Risk of Thyroid Cancer Based on Thyroid Ultrasound Imaging Characteristics: Results of a Population-Based Study 
JAMA internal medicine  2013;173(19):1788-1796.
There is wide variation in the management of thyroid nodules identified on ultrasound imaging.
To quantify the risk of thyroid cancer associated with thyroid nodules based on their ultrasound characteristics.
Retrospective case-control study of patients who underwent thyroid ultrasound between January 1st, 2000 and March 30th, 2005. Thyroid cancers were identified through linkage with the California Cancer Registry.
8 806 patients underwent 11 618 thyroid ultrasound examinations during the study period including 105 subsequently diagnosed with thyroid cancer. Thyroid nodules were common in patients diagnosed with cancer (97%) and patients not diagnosed with thyroid cancer (56%). Three ultrasound nodule characteristics–micro-calcifications (odds ratio [OR] 8.1 [95% CI 3.8, 17.3]), size greater than 2 cm (OR 3.6 [95% CI 1.7, 7.6]) and an entirely solid composition (OR 4.0 [95% CI 1.7, 9.2] - were the only findings associated with the risk of thyroid cancer. If a single characteristic is used as an indication for biopsy, most patients with thyroid cancer would be detected (sensitivity .88 [95% CI .80, .94]) with a high false positive rate (.44 [95% CI .43, .45]) and a low likelihood ratio positive (2.0 [95% CI 1.8, 2.2]), and 56 biopsies will be performed per cancer diagnosed. If two characteristics were required for biopsy, the sensitivity and false positive rates would be lower (sensitivity 0.52 [95% CI 0.42, 0.62]; false positive rate 0.07 [95% CI 0.07, 0.08]), the likelihood ratio positive would be higher (7.1 [95% CI 6.2, 8.2]), and only 16 biopsies will be performed per cancer diagnosed. In comparison to performing biopsy of all thyroid nodules greater than 5 mm, adoption of this more stringent rule requiring two abnormal nodule characteristics to prompt biopsy would reduce unnecessary biopsies by 90%, while maintaining a low risk of cancer, 5 per 1000 patients, for whom biopsy is deferred.
Thyroid ultrasound could be used to identify patients who have a low risk of cancer for whom biopsy could be deferred. Based on these results, these findings should be validated in a large prospective cohort.
PMCID: PMC3936789  PMID: 23978950
4.  Strong Relationship between Oral Dose and Tenofovir Hair Levels in a Randomized Trial: Hair as a Potential Adherence Measure for Pre-Exposure Prophylaxis (PrEP) 
PLoS ONE  2014;9(1):e83736.
Pre-exposure prophylaxis (PrEP) trials using tenofovir-based regimens have demonstrated that high levels of adherence are required to evaluate efficacy; the incorporation of objective biomarkers of adherence in trial design has been essential to interpretation, given the inaccuracy of self-report. Antiretroviral measurements in scalp hair have been useful as a marker of long-term exposure in the HIV treatment setting, and hair samples are relatively easy and inexpensive to collect, transport, and store for analysis. To evaluate the relationship between dose and tenofovir concentrations in hair, we examined the dose proportionality of tenofovir in hair in healthy, HIV-uninfected adults.
A phase I, crossover pharmacokinetic study was performed in 24 HIV-negative adults receiving directly-observed oral tenofovir tablets administered 2, 4, and 7 doses/week for 6 weeks, with a ≥3-week break between periods. Small samples of hair were collected after each six-week period and analyzed for tenofovir concentrations. Geometric-mean-ratios compared levels between each pair of dosing conditions. Intensive plasma pharmacokinetic studies were performed during the daily-dosing period to calculate areas-under-the-time-concentration curves (AUCs).
Over 90% of doses were observed per protocol. Median tenofovir concentrations in hair increased monotonically with dose. A log-linear relationship was seen between dose and hair levels, with an estimated 76% (95% CI 60–93%) increase in hair level per 2-fold dose increase. Tenofovir plasma AUCs modestly predicted drug concentrations in hair.
This study found a strong linear relationship between frequency of dosing and tenofovir levels in scalp hair. The analysis of quantitative drug levels in hair has the potential to improve adherence measurement in the PrEP field and may be helpful in determining exposure thresholds for protection and explaining failures in PrEP trials. Hair measures for adherence monitoring may also facilitate adherence measurement in real-world settings and merit further investigation in upcoming PrEP implementation studies and programs.
Trial Registration +NCT00903084.
PMCID: PMC3885443  PMID: 24421901
5.  A Single-Nucleotide Polymorphism in CYP2B6 Leads to >3-Fold Increases in Efavirenz Concentrations in Plasma and Hair Among HIV-Infected Women 
The Journal of Infectious Diseases  2012;206(9):1453-1461.
Background. Efavirenz exhibits marked interindividual variability in plasma levels and toxicities. Prior pharmacogenetic studies usually measure exposure via single plasma levels, examine limited numbers of polymorphisms, and rarely model multiple contributors. We analyzed numerous genetic and nongenetic factors impacting short-term and long-term exposure in a large heterogeneous population of human immunodeficiency virus (HIV)–infected women.
Methods. We performed 24-hour intensive pharmacokinetic studies in 111 women receiving efavirenz under actual-use conditions and calculated the area-under-the-concentration-time curve (AUC) to assess short-term exposure; the efavirenz concentration in hair was measured to estimate long-term exposure. A total of 182 single-nucleotide polymorphisms (SNPs) and 45 haplotypes in 9 genes were analyzed in relationship to exposure by use of multivariate models that included a number of nongenetic factors.
Results. Efavirenz AUCs increased 1.26-fold per doubling of the alanine aminotransferase level and 1.23-fold with orange and/or orange juice consumption. Individuals with the CYP2B6 516TT genotype displayed 3.5-fold increases in AUCs and 3.2-fold increases in hair concentrations, compared with individuals with the TG/GG genotype. Another SNP in CYP2B6 (983TT) and a p-glycoprotein haplotype affected AUCs without substantially altering long-term exposure.
Conclusions. This comprehensive pharmacogenomics study showed that individuals with the CYP2B6 516TT genotype displayed >3-fold increases in both short-term and long-term efavirenz exposure, signifying durable effects. Pharmacogenetic testing combined with monitoring of hair levels may improve efavirenz outcomes and reduce toxicities.
PMCID: PMC3466997  PMID: 22927450
6.  Trends and Outcomes Associated With Serum Albumin Concentration Among Incident Dialysis Patients in the United States 
Objective and Methods:
Serum albumin concentrations are associated with mortality, and respond to nutritional and inflammatory states. To explore whether changing demographics and practice patterns in dialysis have influenced serum albumin concentrations, we analyzed trends in serum albumin among incident patients on dialysis from 1995 through 2004.
Mean serum albumin concentrations declined significantly over time, even after accounting for changes in age, diabetes, body size, and other factors. Although laboratory assays were not uniform within or across years, serum albumin declined over time, regardless of the reported laboratory lower limit of normal. Moreover, serum albumin retained its potent association with mortality over time. Lower serum albumin was especially hazardous among younger patients and blacks, and was less hazardous among persons with diabetes as a primary cause of kidney disease.
Despite higher body weights and the initiation of dialysis earlier in the course of progressive chronic kidney disease, hypoalbuminemia remains common and hazardous to persons starting dialysis.
PMCID: PMC3786208  PMID: 18558296
7.  Influence of Cannabis Use on Severity of Hepatitis C Disease 
Complications of hepatitis C virus (HCV) infection are primarily related to the development of advanced fibrosis.
Baseline data from a prospective community-based cohort study of 204 persons with chronic hepatitis C virus (HCV) infection were used for analysis. The outcome was fibrosis score on biopsy and the primary predictor evaluated was daily cannabis use.
The median age of the cohort was 46.8 years, 69.1% were male, 49.0% were Caucasian, and the presumed route of infection was injection drug use in 70.1%. The median lifetime duration and average daily use of alcohol were 29.1 years and 1.94 drink equivalents per day. Cannabis use frequency (within prior 12 months) was daily in 13.7%, occasional in 45.1%, and never in 41.2%. Fibrosis stage, assessed by Ishak method, was F0, F1–2 and F3–6 in 27.5%, 55.4% and 17.2% of subjects, respectively. Daily compared to non-daily cannabis use was significantly associated with moderate to severe fibrosis (F3–6 versus F1–2) in univariate [OR = 3.21 (95% CI, 1.20–8.56), p = 0.020] and multivariate analyses (OR = 6.78, (1.89–24.31), p=0.003). Other independent predictors of F3–6 were ≥11 portal tracts (compared to <5, OR = 6.92 (1.34–35.7), p=0.021] and lifetime duration of moderate and heavy alcohol use [OR per decade = 1.72 (1.02–2.90), p=0.044].
We conclude that daily cannabis use is strongly associated with moderate to severe fibrosis and that HCV-infected individuals should be counseled to reduce or abstain from cannabis use.
PMCID: PMC3184401  PMID: 18166478
fibrosis; alcohol; viral load; marijuana; cirrhosis
8.  Citalopram is not Effective Therapy for Non-Depressed Patients with Irritable Bowel Syndrome 
Background & Aims
Data are conflicting on the benefit of selective serotonin reuptake inhibitors (SSRIs) for patients with irritable bowel syndrome (IBS); the role of visceral sensitivity in IBS pathophysiology is unclear. We assessed the effects of citalopram and the relationships between, symptoms, and quality of life (QOL), and rectal sensitivity in non-depressed patients with IBS.
Patients from primary, secondary and tertiary care centers were randomly assigned to groups given citalopram (20 mg/day for 4 weeks, then 40 mg/day for 4 weeks) or placebo. The study was double masked with concealed allocation. Symptoms were assessed weekly; IBS-QOL and rectal sensation were determined from barostat measurements made at the beginning and end of the study.
Patients that received citalopram did not have a higher rate of adequate relief from IBS symptoms than subjects that received placebo (12/27, 44% vs 15/27, 56% respectively; P=0.59), regardless of IBS subtype. The odds ratio for weekly response to citalopram vs placebo was 0.80 (95% confidence interval [CI] 0.61–1.04). Citalopram did not reduce specific symptoms or increase IBS-QOL scores; it had no effect on rectal compliance and a minimal effect on sensation. Changes in IBS-QOL score and pressure-eliciting pain were correlated (r=0.33, 95% CI 0.03–0.57); changes in symptoms and rectal sensitivity or IBS-QOL scores were not correlated.
Citalopram was not superior to placebo in treating non-depressed IBS patients. Changes in symptoms were not correlated with changes in rectal sensation assessed by barostat; Any benefit of citalopram in non-depressed IBS patients is likely to be modest.
PMCID: PMC2818161  PMID: 19765674
9.  Self-Perception of Body Fat Changes and HAART Adherence in the Women’s Interagency HIV Study 
AIDS and behavior  2008;13(1):53-59.
To determine the association of self-perceived fat gain or fat loss in central and peripheral body sites with adherence to highly active antiretroviral therapy (HAART) in HIV-seropositive women. 1,671 women from the Women’s Interagency HIV Study who reported HAART use between April 1999 and March 2006 were studied. Adherence was defined as report of taking HAART ≥ 95% of the time during the prior 6 months. Participant report of any increase or decrease in the chest, abdomen, or upper back in the prior 6 months defined central fat gain and central fat loss, respectively. Report of any increase or decrease in the face, arms, legs or buttocks in the prior 6 months defined peripheral fat gain or peripheral fat loss. Younger age, being African-American (vs. White non-Hispanic), a history of IDU, higher HIV RNA at the previous visit, and alcohol consumption were significant predictors of HAART non-adherence (P <0.05). After multivariate adjustment, self-perception of central fat gain was associated with a 1.5-fold increased odds of HAART non-adherence compared to no change. Perception of fat gain in the abdomen was the strongest predictor of HAART non-adherence when the individual body sites were studied. Women who perceive central fat gain particularly in the abdomen are at risk for decreased adherence to HAART despite recent evidence to suggest that HIV and specific antiretroviral drugs are more commonly associated with fat loss than fat gain.
PMCID: PMC2902995  PMID: 18688706
Lipodystrophy; HIV; Women; HAART adherence; body image perception
10.  Connexin43 PDZ2 Binding Domain Mutants Create Functional Gap Junctions and Exhibit Altered Phosphorylation 
Cell communication & adhesion  2004;11(2-4):67-87.
Connexin43 (Cx43) is the most abundantly expressed gap junction protein. The C-terminal tail of Cx43 is important for regulation of gap junctions via phosphorylation of specific tyrosine and serine residues and through interactions with cellular proteins. The C-terminus of Cx43 has been shown to interact with the PDZ2 domain of the tight and adherens junction associated zona occludens 1 (ZO-1) protein. Analysis of the PDZ2 binding domain of Cx43 indicated that positions −3 and −2, and the final hydrophobic amino acid at the C-terminus, are critical for ZO-1 binding. In addition, the C-termini of connexins 40 and 45, but not Cx32, interacted with ZO-1. To evaluate the functional significance of the Cx43-ZO-1 interaction, Cx43 wild type (Cx43wt) and mutants lacking either the C-terminal hydrophobic isoleucine (Cx43ΔI382) or the last five amino acids (Cx43Δ378–382), required for ZO-1 binding in vitro, were introduced into a Cx43-deficient MDCK cell line. In vitro binding studies and coimmunoprecipitation assays indicated that these Cx43 mutants failed to interact with ZO-1. Confocal and deconvolution microscopy revealed that a fraction of Cx43wt colocalized with ZO-1 at the plasma membrane. A similar colocalization pattern was observed for the Cx43ΔI382 and Cx43Δ378–382 mutants, which were translocated to the plasma membrane and formed functional gap junction channels. The wt and mutant Cx43 appeared to have similar turnover rates. However, the P2 and P3 phosphoisoforms of the Cx43 mutants were significantly reduced compared to Cx43wt. These studies indicated that the interaction of Cx43 with ZO-1 may contribute to the regulation of Cx43 phosphorylation.
PMCID: PMC2880920  PMID: 16247852
Gap junctions; connexin; ZO-1; PDZ domain; phosphorylation
11.  A Novel Connexin43-interacting Protein, CIP75, Which Belongs to the UbL-UBA Protein Family, Regulates the Turnover of Connexin43*S 
The Journal of biological chemistry  2007;283(9):5748-5759.
The degradation of connexin43 (Cx43) has been reported to involve both lysosomal and proteasomal degradation pathways; however, very little is known about the mechanisms regulating these Cx43 degradation pathways. Using yeast two-hybrid, glutathione S-transferase pull-down, and co-immunoprecipitation approaches, we have identified a novel Cx43-interacting protein of ~75 kDa, CIP75. Laser confocal microscopy showed that CIP75 is located primarily at the endoplasmic reticulum, as indicated by the calnexin marker, with Cx43 co-localization in this perinuclear region. CIP75 belongs to the UbL (ubiquitin-like)-UBA (ubiquitin-associated) domain-containing protein family with a N-terminal UbL domain and a C-terminal UBA domain. The UBA domain of CIP75 is the main element mediating the interaction with Cx43, whereas the CIP75-interacting region in Cx43 resides in the PY motif and multiphosphorylation sites located between Lys264 and Asn302. Interestingly, the UbL domain interacts with the S2/RPN1 and S5a/RPN10 protein subunits of the regulatory 19 S proteasome cap subunit of the 26 S proteasome complex. Overexpression experiments suggested that CIP75 is involved in the turnover of Cx43 as measured by a significant stimulation of Cx43 degradation and reduction in its half-life with the opposite effects on Cx43 degradation observed in small interference RNA knockdown experiments.
PMCID: PMC2877505  PMID: 18079109
12.  Akt Phosphorylates Connexin43 on Ser373, a “Mode-1” Binding Site for 14-3-3 
Cell communication & adhesion  2007;14(5):211-226.
Connexin43 (Cx43) is a membrane-spanning protein that forms channels that bridge the gap between adjacent cells and this allows for the intercellular exchange of information. Cx43 is regulated by phosphorylation and by interacting proteins. “Mode-1” interaction with 14-3-3 requires phosphorylation of Ser373 on Cx43 (Park et al. 2006). Akt phosphorylates and targets a number of proteins to interactions with 14-3-3. Here we demonstrate that Akt phosphorylates Cx43 on Ser373 and Ser369; antibodies recognizing Akt-phosphorylated sites or phospho-Ser “mode-1” 14-3-3-binding sites recognize a protein from EGF-treated cells that migrates as Cx43, and GST-14-3-3 binds to Cx43 phosphorylated endogenously in EGF-treated cells. Confocal microscopy supports the co-localization of Cx43 with Akt and with 14-3-3 at the outer edges of gap junctional plaques. These data suggest that Akt could target Cx43 to an interaction with 14-3-3 that may play a role in the forward trafficking of Cx43 multimers and/or their incorporation into existing gap junctional plaques.
PMCID: PMC2673107  PMID: 18163231
Connexin43; Akt; phosphorylation; 14-3-3; “mode-1” binding; protein interactions
13.  Novel Rab GAP-like Protein, CIP85, Interacts with Connexin43 and Induces Its Degradation† 
Biochemistry  2005;44(7):2385-2396.
Gap junctions play critical roles in tissue function and homeostasis. Connexin43 (Cx43) is a major gap junction protein expressed in the mammalian heart and other tissues and may be regulated by its interaction with other cellular proteins. Using the yeast two-hybrid screen, we identified a novel Cx43-interacting protein of 85-kDa, CIP85, which contains a single TBC, SH3, and RUN domain, in addition to a short coiled coil region. Homologues containing this unique combination of domains were found in human, D. melanogaster, and C. elegans. CIP85 mRNA is expressed ubiquitously in mouse and human tissues. In vitro interaction assays and in vivo co-immunoprecipitation experiments confirmed the interaction of endogenous CIP85 with Cx43. In vitro interaction experiments using CIP85 mutants with in-frame deletions of the TBC, SH3, and RUN domains indicated that the SH3 domain of CIP85 is involved in its interaction with Cx43. Conversely, analysis of Cx43 mutants with proline to alanine substitutions in the two proline-rich regions of Cx43 revealed that the P253LSP256 motif is an important determinant of the ability of Cx43 to interact with CIP85. Laser-scanning confocal microscopy showed that CIP85 colocalized with Cx43 at the cell periphery, particularly in areas reminiscent of gap junction plaques. The functional importance of the interaction between CIP85 and Cx43 was suggested by the observation that CIP85 appears to induce the turnover of Cx43 through the lysosomal pathway.
PMCID: PMC2670246  PMID: 15709751

Results 1-13 (13)