High prevalence of suicide risk in people living with HIV: who is at higher risk?

A cross-sectional study was developed to evaluate suicide risk and associated factors in HIV/AIDS patients at a regional reference center for the treatment of HIV/AIDS in southern Brazil. We assessed 211 patients in regard to suicide risk, clinical and sociodemographic characteristics, drug use, depression, and anxiety. Suicide risk was assessed with Mini International Neuropsychiatric Interview, Module C. Multivariate analysis was performed using Poisson regression. Of the total sample, 34.1% were at risk of suicide. In the multivariate analysis, the following variables were independently associated with suicide risk: female gender; age up to 47 years; unemployment; indicative of anxiety; indicative of depression; and abuse or addiction on psychoactive substances. Suicide risk is high in this population. Psychosocial factors should be included in the physical and clinical evaluation, given their strong association with suicide risk.     

Identification of chemopreventive agents by screening for induction of glutathione-S-transferase as a biomarker

For selection and identification of potential chemopreventive agents, a biochemical assay using induction of a phase II enzyme, glutathione-S-transferase (GST) in a liver cell culture is described. A normal human liver cell line (Chang liver cells) was selected as the candidate cell line for induction of GST (liver tissues are abundant in GST) by a known chemopreventive agent, oltipraz. Exponentially growing cells plated for 24 hours are exposed to various doses of a chemopreventive agent for an additional 24 hours, homogenized by sonication, and the homogenate is assayed for GST in a modified microplate enzyme assay using CDNB (1-chloro-2,4-dinitrobenzene) as a substrate. A concurrent protein assay is performed to determine the specific enzyme activity. As the assay is modified from a spectrophotometric assay to a microplate assay, it is reliable, sensitive and fast, a significant number of test agents can be screened in a short time.     

In vitro genotoxicity of Melaleuca alternifolia essential oil in human lymphocytes

Ethnopharmacological relevance

The volatile essential oil derived from the plant Melaleuca alternifolia, also called tea tree oil (TTO), is largely employed for its antimicrobial properties against several human pathogens. It is used in many topical formulations to treat cutaneous infections.

Aim of the study

Since very few studies have been done on the safety and toxicity of the crude Melaleuca alternifolia essential oil, current investigation evaluates the possible genotoxic effects of TTO in human lymphocyte cultures.

Material and methods

The composition of current TTO sample was determined by GC/MS and NMR. The level of cytotoxicity in TTO treated cultures was determined by decrease of mitotic index when compared to that in negative control. The genotoxic potential of TTO was assessed by the in vitro mammalian cell micronucleus and the chromosome aberrations (CA) tests.

Results

Twenty-seven compounds were identified, accounting for 98.9% of the constituents. Terpinen-4-ol (42.8%), γ-terpinene (20.4%), p-cymene (9.6%), α-terpinene (7.9%), 1,8-cineole (3%), α-terpineol (2.8%) and α-pinene (2.4%) were the major compounds of the oil sample. None of the tested TTO concentrations (95 μg/ml, 182 μg/ml and 365 μg/ml) caused a significant increase in the observed frequencies of micronuclei when compared to those in the untreated cultures (negative control). Additionally, no significant differences regarding the frequencies of CA were observed among the tested TTO concentrations and the negative control.

Conclusions

Results demonstrate that TTO, in the tested concentrations, is not genotoxic in in vitro mammalian cells.     

Applications and Limitations of Blood Eosinophilia for the Diagnosis of Acute Cellular Rejection in Liver Transplantation

This study evaluates the predictive value of the blood eosinophil count in the diagnosis of acute cellular rejection, its value as a marker of response to treatment, the diagnostic use in a subgroup of patients with normal transaminases and compares blood eosinophilia in patients with and without hepatitis C virus infection. A consecutive cohort of 101 liver transplant patients, 275 liver biopsies, and blood eosinophils recorded on the day or one day before biopsy were analyzed. An elevated eosinophil count has a positive predictive value for acute cellular rejection of 82%. A normal eosinophil count excludes moderate/severe rejection with a predictive value of 86%. The eosinophil count decreases in 69% of patients following treatment of acute cellular rejection with corticosteroids irrespective of treatment outcome. Acute cellular rejection in the presence of an elevated eosinophil count occurs significantly less often (p = 0.007) in patients with hepatitis C virus. An elevated eosinophil count is a valuable marker of acute cellular rejection. However, blood eosinophil levels should not be used to predict acute cellular rejection following treatment with corticosteroids. Blood eosinophilia, seen less often in patients with hepatitis C virus, may reflect an over-diagnosis of acute cellular rejection in these patients.     

Protective effects of guanosine against sepsis-induced damage in rat brain and cognitive impairment

The development of cognitive impairment in sepsis is associated with neurotoxic effects caused by oxidative stress. We have assessed the effects of acute and extended administration of guanosine (GUA) on brain oxidative stress parameters and cognitive impairment in rats submitted to sepsis by cecal ligation and perforation (CLP). To achieve this goal, male Wistar rats underwent either sham operation or CLP with GUA. Rats subjected to CLP were treated with intraperitoneal injection of GUA (8 mg/kg after CLP) or vehicle. Twelve and 24 h after CLP, the rats were sacrificed, and samples from brain (hippocampus, striatum, cerebellum, prefrontal cortex and cortex) were obtained and assayed for thiobarbituric acid reactive species (TBARS) formation and protein carbonyls. On the 10th day, another group of rats was submitted to the behavioral tasks. GUA administration reduced TBARS and carbonyl levels in some brain regions between 12 and 24 h after CLP, and ameliorated cognitive impairment evaluated 10 days after CLP. Our data provide the first experimental demonstration that GUA was able to reduce the consequences of CLP-induced sepsis in rats, by decreasing oxidative stress parameters in the brain and recovering the memory impairment.     

Mu and alpha rhythm in comatose children

Three anoxic comatose children had EEG alpha-like activity and in two of them mu rhythm was recorded. The paradoxical appearance of these electrical activities in comatose children seems to indicate a grave prognosis. A possible role for barbiturate treatment in this phenomenon is not excluded.     

Reliability,Construct and Predictive Validity of the Hong Kong Chinese Orebro Musculoskeletal Pain Screening Questionnaire

Purpose The aim of this study was to evaluate the reliability, construct validity and predictive validity of the Hong Kong Chinese version of the Orebro Musculoskeletal Pain Screening Questionnaire (COMPSQ-HK). Methods The COMPSQ-HK was developed using the forward–backward translation. Internal consistency was assessed using Cronbach’s alpha and test–retest reliability was examined using intraclass correlation coefficient with one-way random-effects model (ICC_1,1), minimum detectable change (MDC) and 95% limits of agreement (LoA). Construct validity was evaluated by correlating the COMPSQ-HK with the Numeric Pain Rating Scale, Roland-Morris Disability Questionnaire, Northwick Park Neck Pain Questionnaire, Tampa Scale for Kinesiophobia, and Medical Outcomes Study Short Form 12. The predictive validity was investigated using receiver operating characteristics (ROC) curve analyses with sick leave?>60 days and return-to-work for ≥4 consecutive weeks as outcomes at 1 year follow-up. The areas under the curve (AUC) were calculated. Results The COMPSQ-HK was administered to 305 patients with acute/subacute low back pain and 160 patients with acute/subacute neck pain. The Cronbach’s alphas and ICC_1,1 ranged from 0.83 to 0.84 and 0.81 to 0.92 respectively. The MDC were 32.1 and 21.1. The 95% LoA were ?32.4 to 31.8 and ?15.4 to 26.7. The Pearson r ranged from 0.333 to 0.697 in absolute value. The AUC for the ROC curve analyses ranged from 0.59 to 0.71. Conclusions The COMPSQ-HK has good internal consistency, moderate test–retest reliability, satisfactory construct validity and predictive validity as a screening tool for patients with back and neck pain at risk of chronic disability.     

Assessment of bendamustine-induced genotoxicity in eukaryotic cells

Bendamustine, an anticancer drug with alkylating properties, is widely used to treat hematological malignancies. Since the nitrogen mustard family alkylators induce DNA damages and have been associated with an elevated risk of second malignancy, current study evaluates the cytotoxic, mutagenic, and recombinogenic effects of bendamustine by using, respectively the mitotic index assay, the in vitro mammalian cell micronucleus test (Mnvit) and the chromosome aberration (CA) test in human peripheral lymphocytes, and the in vivo homozygotization assay in Aspergillus nidulans, which detects the loss of heterozygosity (LOH) due to somatic recombination. Bendamustine (6.0?µg/ml, 9.0?µg/ml, and 12.0?µg/ml) induced a statistically significant concentration-related increase in the frequencies of micronuclei and a significant reduction in the cytokinesis block proliferation index (CBPI) rates when compared to negative control. In the CA test, bendamustine significantly increased the frequencies of structural aberrations at the three tested concentrations when compared to the negative control. Aspergillus nidulans diploids, obtained after bendamustine treatment (6.0?µg/ml, 12.0?µg/ml, and 24.0?µg/ml), produced, after haploidization, homozygotization index (HI) rates higher than 2.0 and significantly different from the negative control. Since bendamustine showed genotoxic effects in all tested concentrations, two of them corresponding to the peak plasma concentrations observed in cancer patients treated with bendamustine, data provided in the current research work may be useful to identify the most appropriate dosage regimen to achieve the efficacy and safety of this anticancer medication.