Repeated low-dose skin exposure is an effective sensitizing stimulus, a factor to be taken into account in predicting sensitization risk

BACKGROUND

Contact sensitization by ingredients in personal products is an important clinical problem. It is not clear how sensitization is induced by the generally low concentrations at which they occur but it might be the result of repeated exposure.

OBJECTIVES

To compare the strength of contact sensitization induced by a single exposure to 2,4-dinitrochlorobenzene (DNCB) (60 microg cm(-2)) or three repeated exposures to a subsensitizing dose (10 microg cm(-2)).

METHODS

Two groups (n = 10) of healthy adult volunteers were randomized to receive either a single patch of DNCB 60 microg cm(-2) or three once-weekly applications to the same site of 10 microg cm(-2) DCNB. Four weeks after the last application, sensitization was quantified by measurement of responses (skinfold thickness) to a graded series of four challenge doses.

RESULTS

All the volunteers were sensitized and the strength of the responses was virtually identical between the groups.

CONCLUSIONS

The same degree of sensitization was induced by three exposures to DNCB 10 microg cm(-2) as by one exposure to 60 microg cm(-2) of DNCB. Thus repeated exposure to low doses of contact sensitizers may increase the sensitizing potency. This must be taken into account in future risk assessments.

Drug use patterns among Thai illicit drug injectors amidst increased police presence

Thailand has traditionally pursued an aggressive enforcement-based anti-illicit drug policy in an effort to make the country "drug-free." In light of this ongoing approach, we sought to assess impacts of enforcement on drug use behaviors among a cohort of injection drug users (IDU) in Thailand. We examined drug use patterns among IDU participating in a cross-sectional study conducted in Bangkok (n = 252). Participants were asked to provide data regarding patterns of drug use in the previous six months, including types of drugs consumed, method of consumption, frequency of use, and weekly income spent on drugs. We also conducted bivariate analyses to identify a possible effect of a reported increase in police presence on measures of drug use and related risk behaviors among study participants. One hundred fifty-five (61.5%) individuals reported injection heroin use and 132 (52.4%) individuals reported injection midazolam use at least daily in the past six months. Additionally, 86 (34.1%) individuals reported at least daily injection Yaba and Ice (i.e., methamphetamine) use. Participants in our study reported high levels of illicit drug use, including the injection of both illicit and licit drugs. In bivariate analyses, no association between increased police presence and drug use behaviors was observed. These findings demonstrate high ongoing rates of drug injecting in Thailand despite reports of increased levels of strict enforcement and enforcement-related violence, and raise questions regarding the merits of this approach.

Factors Associated with Public Injecting Among Users of Vancouver's Supervised Injection Facility

BACKGROUND

We evaluated factors associated with public drug injection among a cohort of injection drug users (SEOSI) originally recruited from within Vancouver's supervised injecting facility (SIF).

METHODS

We used univariate statistics and logistic regression to examine factors associated with public drug injection among SEOSI participants.

FINDINGS

Between June 2004 and July 2005, 714 IDU were followed up as part of SEOSI. In multivariate analyses, factors associated with public drug injection included homelessness (adjusted odds ratio (aOR) = 3.10; p < .001), syringe lending (aOR = 5.39; p < .001), requiring help injecting (aOR = 1.60; p = .05), and reporting that wait times affected frequency of SIF use (aOR = 3.26; p < .001).

INTERPRETATION

Persistent public injection was independently associated with elevated HIV risk behaviors, as well as programmatic factors that limit SIF use. SIF program expansion may further help to reduce persistent risk behaviors and the community concerns related to public injection drug use.

Analysis of neuronal proliferation, migration and differentiation in the postnatal brain using equine infectious anemia virus-based lentiviral vectors

Ongoing neurogenesis in discrete sectors of the adult central nervous system depends on the mitotic activity of an elusive population of adult stem cells. The existence of adult neural stem cells provides an alternative approach to transplantation of embryonic stem cells in cell-based therapies. Owing to the limited intrinsic fate of adult stem cells and inhibitory nature of the adult brain for neurogenesis, accommodation for circuit replacement in the brain will require genetic and epigenetic manipulation. Here, we show that a replication-incompetent Equine Infectious Anemia Virus (EIAV) is highly suitable for stable and persistent gene transfer to adult neural stem cells. The transduced regions were free of long-lasting neuroimmune responses to EIAV. Transduction in the subventricular zone was specific to the stem cell niche, but spared the progeny of adult neural stem cells that includes transit amplifying progenitors (TAPs) and migrating neuroblasts. With time, EIAV-transduced stem cells passed on the transgene to TAPs and migrating neuroblasts, which ultimately differentiated into neurons in the olfactory bulbs. We show that EIAV is highly suitable for discovery and assessment of mechanisms that regulate proliferation, migration and differentiation in the postnatal brain.

An exploration of Pap smear history and behavior of patients with newly diagnosed cervical cancer in Taiwan

e20582

Background: The national health insurance policy has provided a yearly Pap smear for women >= 30 years old since 1994 in Taiwan, yet the coverage rate is still unsatisfactory. The purpose of this study is (1) to investigate the Pap smear screening history of women newly diagnosed with cervical cancer and (2) to examine factors that influence participation in Pap smear screening program in these women. Methods: Patients primarily treated for cervical cancer at Chang Gung Memorial Hospital between November 2006 and June 2007 were enrolled into this prospective study. Questionnaires included (1) socio-demographic data, and (2) knowledge on Pap smear and cervical cancer. Results: Two hundred sixty-nine patients were eligible for analysis. The median age was 51 years old (range, 25–83). Of the 269 patients, 147 (54.6%) had never had a Pap smear before diagnosis, and 35 (13.0%) did not know about Pap smear. Socio-demographic factors that significantly influenced number of previous Pap smear screening (0 vs >=1) were education level, income less than 600 U.S. dollars per month, menopaused, multiple sexual partners, and increase number of sexual partners of the male consort. Of the 147 never received Pap women, the most common reasons were thought that Pap smear screening was not necessary (46.3%), embarrassment (42.0%), busy (43.5%), and worry about the screening findings (20.4%). Of the 122 patients who have received Pap smear, 56.6% patients thought that Pap smear screening was necessary, 35.2% patients worried about the disease, 24.6% were alert on their check-ups, and 20.5% did the screening for the convenience to nearby clinics. Conclusions: Public health organizations in Taiwan should put more efforts to provide women in low education level, low income and multiple sexual partners with information on Pap smear.

No significant financial relationships to disclose.

Phase 1 study of LY317615 (enzastaurin) and temozolomide in patients with gliomas - EORTC trial 26054

e13005

Background: Enzastaurin (Enz) is a small selective inhibitor of protein kinase C (PKC). Synergy with temozolomide (TMZ) has been demonstrated in vitro. This phase I trial investigated optimal dosing and toxicity when Enz was combined with a standard TMZ regimen. Methods: Patients (pts) with recurrent high-grade glioma or newly diagnosed disease not amenable to radiotherapy (RT) and WHO PS 0–1 were eligible. Pts on EIAEDs were excluded. Two dose levels (DL) of Enz were explored. DL1: Loading dose 500 mg followed by 250 mg daily. DL2: Loading dose 1,125 mg followed by 500 mg daily. TMZ was given at 150 mg/m2 d1-d5 every 28 days in cycle 1, escalating to 200 mg/m2 in subsequent cycles. Dose-limiting toxicity (DLT) was defined by CTCAE 3.0 criteria in the first two cycles as (1) any non haematological toxicity grade 3/4 (2) ANC < 500/mm3 (3) thrombocytopenia grade 3/4 (4) any toxicity reducing drug dose intensity to <80%. Results: 15 pts were included, three at DL1, 12 at DL2. 13 pts had received prior RT, seven prior chemotherapy, and two were newly diagnosed. Median number of cycles was four (range 2–8).Treatment is ongoing in five pts. TMZ dose was escalated in all pts with no DLT. Modest and reversible thrombocytopenia was the most frequent toxicity, occurring in seven pts (3 @ Gd 1, 3 @ Gd2, 1 @ Gd 3) and led to TMZ dose reduction in two pts and treatment delays in four pts (multiple in 2). One pt discontinued after three cycles due to persistent thrombocytopenia. Five pts developed neutropenia not requiring dose modification. Two pts developed hyperbilirubinemia. Six SAE's (3 at each DL) were recorded, and one death (DL2). None was considered treatment related. Two pts showed a partial response, six pts stable disease. Conclusions: Enz can be safely combined with standard TMZ regimen. Results of the just completed phase I part with Enz 250 mg twice daily dosing will also be presented at the meeting.

[Table: see text]

Incarceration experiences in a cohort of active injection drug users

BACKGROUND

Incarceration has been associated with a number of health-related harms among injection drug users (IDU). However, little is known about the prevalence and correlates of incarceration among community-based samples of IDU.

METHODS

We examined the prevalence and correlates of recent incarceration among IDU in the Scientific Evaluation of Supervised Injecting (SEOSI) cohort examined between 1 July 2004 and 30 June 2006 using generalised estimating equations (GEE).

RESULTS

A total of 902 individuals were included in the analysis, of whom 255 (28.72%) were female and 536 (59.42%) reported a history of incarceration. In a multivariate GEE model, recent incarceration was associated positively and independently with a number of high-risk drug using behaviours, including syringe sharing.

CONCLUSIONS

An alarmingly high proportion of active IDU reported recent incarceration and injecting while incarcerated. Recent incarceration was associated independently with syringe sharing. These findings add further evidence to repeated demands for an expansion of appropriate harm-reduction measures in Canada's prisons.

Low uptake of treatment for hepatitis C virus infection in a large community-based study of inner city residents

Despite the availability of effective therapy for hepatitis C virus (HCV) infection, there are little data on the uptake of treatment. We evaluated factors associated with HCV infection and the uptake of HCV treatment in a large community-based inner city cohort in Vancouver, Canada. The Community Health and Safety Evaluation is a cohort study of inner city residents recruited from January 2003 to June 2004. HIV and HCV status and information on prescriptions for HCV treatment were determined through linkage with provincial databases. HCV prevalence was calculated and factors associated with HCV infection were identified. HCV treatment uptake and incidence of HCV infection from January 2000 to December 2004 were expressed in terms of person-years of observation. Among 2913 individuals, HCV antibody testing was performed in 2118 and the HCV seroprevalence was 64.2% (1360 of 2118). In total, 1.1% of HCV antibody-positive individuals (15 of 1360) initiated treatment for HCV infection from January 2000 to December 2004 [0.28 cases per 100 person-years (95% CI, 0.15-0.46)]. Three of 15 (20.0%) treated individuals achieved a sustained virological response. During the same period, the incidence of HCV infection was 7.26 cases (95% CI, 5.72-8.80) per 100 person-years. Overall, the rate of new HCV seroconversions in this cohort in the study period was about 25 times the rate of HCV treatment uptake. There are extremely low rates of HCV treatment initiation and very limited effectiveness, despite a high prevalence of HCV infection in this large community-based cohort of inner city residents with access to universal healthcare.

Pulmonary hypertension associated with lung transplantation obliterative bronchiolitis and vascular remodeling of the allograft

Pathologic obliterative bronchiolitis (OB)/Bronchiolitis obliterans syndrome (pathologic OB/BOS) is the major obstacle to long-term survival post-lung transplantation (LT). Our group has demonstrated that pulmonary hypertension (PH) complicates the course of chronic inflammatory lung diseases that have similarities to pathologic OB/BOS and that vascular remodeling of the bronchial circulation occurs during BOS. Consequently, we hypothesized that PH is associated with pathologic OB/BOS and may result from a vasculopathy of the allograft pulmonary circulation. We conducted a single-center, retrospective study and examined the presence of PH and vasculopathy in patients with pathologic OB/BOS. Fifty-two pathologic specimens post-LT were recovered from January 10, 1997 to January 5, 2007 and divided into two groups, those with and without pathologic OB/BOS.PH was defined as a mean pulmonary artery pressure (mPAP) > 25 mmHg by right heart catheterization (RHC) or right ventricular systolic pressure (RVSP) > or = 45 mmHg by transthoracic echocardiogram (TTE). PH was more prevalent in those LT recipients with pathologic OB/BOS (72% vs. 0%, p = 0.003). Furthermore, pulmonary arteriopathy and venopathy were more prevalent in patients with pathologic OB/BOS (84% vs. 4%, p < 0.0001, and 77% vs. 35%, p = 0.004, respectively). PH is common in LT recipients with pathologic OB/BOS and is associated with a vasculopathy of the allograft pulmonary circulation.