Association between polymorphisms in arsenic metabolism genes and urinary arsenic methylation profiles in girls and boys chronically exposed to arsenic

Disease manifestations or susceptibilities often differ among individuals exposed to the same concentrations of arsenic (As). These differences have been associated with several factors including As metabolism, sex, age, genetic variants, nutritional status, smoking, and others. This study evaluated the associations between four As metabolism‐related gene polymorphisms/null genotypes with urinary As methylation profiles in girls and boys chronically exposed to As. In a total of 332 children aged 6–12 years, the frequency of AS3MT, GSTO1, GSTT1, and GSTM1 polymorphisms/null genotypes and As urinary metabolites were measured. The results revealed that total As and monomethyl metabolites of As (MMA) levels were higher in boys than in girls. No differences in the frequency of the evaluated polymorphisms were found between girls and boys. In AS3MT‐Met287Thr carriers, %MMA levels were higher and second methylation levels (defined as dimethylarsinic acid divided by MMA) were lower. In children with the GSTM1 null genotype, second methylation levels were higher. In boys, a positive association between the AS3MT‐Met287Thr polymorphism with %MMA and between the GSTO1‐Glu155del and As^v was found; whereas, a negative relationship was identified between AS3MT‐Met287Thr and second methylation profiles. In girls, a positive association was found between the GSTO1‐Ala140Asp polymorphism with second methylation levels. In conclusion, our data indicate that gender, high As exposure levels, and polymorphisms in the evaluated genes negatively influenced As metabolism. Environ. Mol. Mutagen. 57:516–525, 2016. © 2016 Wiley Periodicals, Inc.     

Functional electrical stimulation as a component of activity-based restorative therapy may preserve function in persons with multiple sclerosis

Objective

To examine the effect of functional electrical stimulation (FES) cycling on disability progression in persons with multiple sclerosis (MS).

Design

Retrospective cohort, 40 participants with mean follow-up of 15 months.

Setting

International Center for Spinal Cord Injury at Kennedy Krieger Institute in Baltimore, a rehabilitation referral center.

Participants

Forty consecutive persons with MS undergoing rehabilitation from 2007 to 2011, with at least two evaluations based on the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI).

Interventions

FES cycling as part of activity-based restorative therapy interventions.

Outcome measures

Change in Expanded Disability Status Scale (EDSS) and ISNCSCI motor, light touch, and pin prick scores from baseline to latest evaluation.

Results

In 71% of patients, activity-based rehabilitation included FES cycling. There was no disability progression on the EDSS. Lower extremity motor scores improved or stabilized in 75% of patients with primary progressive MS (PPMS), 71.4% with secondary progressive MS (SPMS), and 54.5% with relapsing remitting MS (RRMS). Among patients with improved or stabilized lower extremity motor function, PPMS recorded a mean 9% improvement, SPMS 3% and RRMS 6%. In PPMS, use of FES showed trend towards improvement in motor scores (P = 0.070).

Conclusions

FES as part of activity-based rehabilitation may help preserve or improve neurological function in patients with MS.     

NCB-02(standardized Curcumin preparation)protects dinitrochlorobenzene-induced colitis through down-regulation of NFκ-B and iNOS

AIM:To evaluate the efficacy and mechanism of action of NCB-02,a standardized Curcumin preparation,against 2,4-dinitrochlorobenzene(DNCB)-induced ulcerative colitis in rats.METHODS:Ulcerative colitis was induced in male rats by sensitizing with topical application of DNCB in acetone for 14 d and intra-colonol challenge with DNCB on day 15.A separate group of animals with vehicle treatment in similar fashion served as control group.Colitis rats were divided into different groups and treated with NCB-02 at doses of 25,50 and 100 mg/kg b.wt p.o.for 10 d.Sulfasalazine at a dose of 100 mg/kg b.wt for 10 d served as a reference group.On day 10 after respective assigned treatment,all the animals were euthanized and the length of the colon,weight of entire colon and distal 8 cm of the colon were recorded.The distal part of the colon was immediately observed under a stereomicroscope and the degree of damage was scored.Further distal 8 cm of the colon was subject to the determination of colonic myeloperoxidase(MPO),lipid peroxidation(LPO)and alkaline phosphatase (ALP)activities.A small piece of the sample from distal colon of each animal was fixed in 10% neutral buffered formalin and embedded in paraffin wax and sectioned for immunohistochemical examination of NFκ-B and iNOS expression.RESULTS:NCB-02 showed a dose dependent protection against DNCB-induced alteration in colon length and weight.NCB-02 treatment also showed a dose dependent protection against the elevated levels of MPO,LPO and ALP,induced by DNCB.NCB-02 demonstrated a significant effect at a dose of 100 mg/kg b.wt.,which was almost equipotent to 100 mg/kg b.wt.of sulfasalazine.Treatment with sulfasalazine and curcumin at a dose of 100 mg/kg b.wt.inhibited the DNCB-induced overexpression of NFκ-B and iNOS in the colon.CONCLUSION:Curcumin treatment ameliorates colonic damage in DNCB-induced colitic rats,an effect associated with an improvement in intestinal oxidative stress and downregulation of colonic NFκ-B and iNOS expression.     

Pre-junctional alpha2-adrenoceptors modulation of the nitrergic transmission in the pig urinary bladder neck

AIMS: To investigate the nitric oxide (NO)-mediated nerve relaxation and its possible modulation by pre-junctional alpha2-adrenoceptors in the pig urinary bladder neck. METHODS: Urothelium-denuded bladder neck strips were dissected, and mounted in isolated organ baths containing a physiological saline solution (PSS) at 37 degrees C and continuously gassed with 5% CO2 and 95% O2, for isometric force recording. The relaxations to transmural nerve stimulation (electrical field stimulation [EFS]) or exogenously applied NO were carried out on strips pre-contracted with 1 microM phenylephrine (PhE) and treated with guanethidine (10 microM) and atropine (0.1 microM), to block noradrenergic neurotransmission and muscarinic receptors, respectively. RESULTS: EFS (0.2-1 Hz, 1 msec duration, 20 sec trains, current output adjusted to 75 mA) evoked frequency-dependent relaxations which were abolished by the neuronal voltage-activated Na+ channel blocker tetrodotoxin (TTX, 1 microM). These responses were potently reduced by the nitric oxide synthase (NOS) inhibitor NG-nitro-L-arginine (L-NOARG, 30 microM) and further reversed by the NO synthesis substrate L-arginine (L-ARG, 3 mM). The alpha2-adrenoceptor agonist BHT-920 (2 microM) reduced the electrically evoked relaxations, its effectiveness being higher on the responses induced by low frequency stimulation. BHT-920-elicited reductions were fully reversed by the alpha2-adrenoceptor antagonist rauwolscine (RAW, 1 microM). Exogenous NO (1 microM-1 mM) induced concentration-dependent relaxations which were not modified by BHT-920, thus eliminating a possible post-junctional modulation. CONCLUSIONS: These results indicate that NO is involved in the non-adrenergic non-cholinergic (NANC) inhibitory neurotransmission in the pig urinary bladder neck, the release of NO from intramural nerves being modulated by pre-junctional alpha2-adrenoceptor stimulation.     

Constituents of Oxandra cf. xylopioides with anti-inflammatory activity

A new triterpenoid (1) derived from 24-methylcycloartanol was isolated from the leaves of Oxandra cf. xylopioides. An unusual structure of the new compound was assigned as 1, for which the name berenjenol is proposed, on the basis of the spectroscopic data of the natural product and of its derivatives 2 and 3. The leaves also afforded the known monoterpene isoespintanol (4). Compounds 1 and 4 significantly reduced the paw edema induced by carrageenan by 64% and 43%, at 3 h, respectively. Moreover, 4 reduced IL-1 beta production by 72% at 100 microM and reduced IL-1 beta mRNA synthesis.     

Duration and predictors of emergency surgical operations - basis for medical management of mass casualty incidents

Background

Hospitals have a critically important role in the management of mass causality incidents (MCI), yet there is little information to assist emergency planners. A significantly limiting factor of a hospital''s capability to treat those affected is its surgical capacity. We therefore intended to provide data about the duration and predictors of life saving operations.

Methods

The data of 20,815 predominantly blunt trauma patients recorded in the Trauma Registry of the German-Trauma-Society was retrospectively analyzed to calculate the duration of life-saving operations as well as their predictors. Inclusion criteria were an ISS ≥ 16 and the performance of relevant ICPM-coded procedures within 6 h of admission.

Results

From 1,228 patients fulfilling the inclusion criteria 1,793 operations could be identified as life-saving operations. Acute injuries to the abdomen accounted for 54.1% followed by head injuries (26.3%), pelvic injuries (11.5%), thoracic injuries (5.0%) and major amputations (3.1%). The mean cut to suture time was 130 min (IQR 65-165 min). Logistic regression revealed 8 variables associated with an emergency operation: AIS of abdomen ≥ 3 (OR 4,00), ISS ≥ 35 (OR 2,94), hemoglobin level ≤ 8 mg/dL (OR 1,40), pulse rate on hospital admission < 40 or > 120/min (OR 1,39), blood pressure on hospital admission < 90 mmHg (OR 1,35), prehospital infusion volume ≥ 2000 ml (OR 1,34), GCS ≤ 8 (OR 1,32) and anisocoria (OR 1,28) on-scene.

Conclusions

The mean operation time of 130 min calculated for emergency life-saving surgical operations provides a realistic guideline for the prospective treatment capacity which can be estimated and projected into an actual incident admission capacity. Knowledge of predictive factors for life-saving emergency operations helps to identify those patients that need most urgent operative treatment in case of blunt MCI.     

Different effects of ascorbate deprivation and classical vascular nitrate tolerance on aldehyde dehydrogenase-catalysed bioactivation of nitroglycerin

Background and purpose:

Vascular tolerance to nitroglycerin (GTN) may be caused by impaired GTN bioactivation due to inactivation of mitochondrial aldehyde dehydrogenase (ALDH2). As relaxation to GTN is reduced but still sensitive to ALDH2 inhibitors in ascorbate deficiency, we compared the contribution of ALDH2 inactivation to GTN hyposensitivity in ascorbate deficiency and classical in vivo nitrate tolerance.

Experimental approach:

Guinea pigs were fed standard or ascorbate-free diet for 2 weeks. Reversibility was tested by feeding ascorbate-deficient animals standard diet for 1 week. Nitrate tolerance was induced by subcutaneous injection of 50 mg·kg⁻¹ GTN 4 times daily for 3 days. Ascorbate levels were determined in plasma, blood vessels, heart and liver. GTN-induced relaxation was measured as isometric tension of aortic rings; vascular GTN biotransformation was assayed as formation of 1,2-and 1,3-glyceryl dinitrate (GDN).

Key results:

Two weeks of ascorbate deprivation had no effect on relaxation to nitric oxide but reduced the potency of GTN ∼10-fold in a fully reversible manner. GTN-induced relaxation was similarly reduced in nitrate tolerance but not further attenuated by ALDH inhibitors. Nitrate tolerance reduced ascorbate plasma levels without affecting ascorbate in blood vessels, liver and heart. GTN denitration was significantly diminished in nitrate-tolerant and ascorbate-deficient rings. However, while the ∼10-fold preferential 1,2-GDN formation, indicative for active ALDH2, had been retained in ascorbate deficiency, selectivity was largely lost in nitrate tolerance.

Conclusions and implications:

These results indicate that nitrate tolerance is associated with ALDH2 inactivation, whereas ascorbate deficiency possibly results in down-regulation of ALDH2 expression.     

Estimation of the age at onset in spinocerebellar ataxia type 2 Cuban patients by survival analysis

Almaguer‐Mederosa LE, Falcón NS, Almira YR, Zaldivar YG, Almarales DC, Góngora EM, Herrera MP, Batallán KE, Armiñán RR, Manresa MV, Cruz GS, Laffita‐Mesa J, Cyuz TM, Chang V, Auburger G, Gispert S, Pérez LV. Estimation of the age at onset in spinocerebellar ataxia type 2 Cuban patients by survival analysis. Previous studies have investigated the close association that exists between CAG repeat number and the age at onset in SCA2 = spinocerebellar ataxia type 2. These studies have focused on affected individuals. To further characterize this association and estimate the risk of a carrier developing SCA2 at a particular age as a function of a specific CAG repeat size, we have analyzed a large group of 924 individuals, including 394 presymptomatic and 530 affected individuals with a CAG repeat length of 32–79 units. Using a Kaplan–Meier survival analysis, we obtained cumulative probability curves for disease manifestation at a particular age for each CAG repeat length in the 34–45 range. These curves were significantly different (p < 0.001) and showed small overlap. All these information may be very valuable in predictive‐testing programs, in the planning of studies for the identification of other genetic and environmental factors as modifiers of age at onset, and in the design of clinical trials for people at enlarged risk for SCA2.     

Rapid Antifungal Susceptibility Determination for Yeast Isolates by Use of Etest Performed Directly on Blood Samples from Patients with Fungemia

We prospectively determined the antifungal susceptibility of yeast isolates causing fungemia using the Etest on direct blood samples (195 prospectively collected and 133 laboratory prepared). We compared the Etest direct (24 h of incubation) with CLSI M27-A3 and the standard Etest methodologies for fluconazole, voriconazole, posaconazole, isavuconazole, caspofungin, and amphotericin B. Strains were classified as susceptible, resistant, or nonsusceptible using CLSI breakpoints (voriconazole breakpoints were used for posaconazole and isavuconazole). Categorical errors between Etest direct and CLSI M27-A3 for azoles were mostly minor. No errors were detected for caspofungin, and high percentages of major errors were detected for amphotericin B. For the azoles, false susceptibility (very major errors) was found in only two (0.6%) isolates (Candida tropicalis and C. glabrata). False resistance (major errors) was detected in 46 (14%) isolates for the three azoles (in 23 [7%] after excluding posaconazole). Etest direct of posaconazole yielded a higher number of major errors than the remaining azoles, especially for C. glabrata, Candida spp., and other yeasts. Excluding C. glabrata, Candida spp., and other yeasts, the remaining species did not yield major errors. Etest direct for fluconazole, voriconazole, isavuconazole, and caspofungin shows potential as an alternative to the CLSI M27-A3 procedure for performing rapid antifungal susceptibility tests on yeast isolates from patients with fungemia. Etest direct is a useful tool to screen for the presence of azole-resistant and caspofungin-nonsusceptible strains.The incidence of fungemia continues to rise in many institutions throughout the world, and Candida is one of the leading pathogens isolated from blood (15, 28). Amphotericin B and fluconazole have been widely used for the treatment of fungemia. However, newly licensed antifungal agents (voriconazole, posaconazole, and the echinocandins) and other azoles currently under investigation (isavuconazole) have expanded the antifungal armamentarium.The mortality rate of fungemia remains high (30%) and is clearly correlated with delayed initiation of effective antifungal therapy (11, 17). Antifungal therapy is considered inappropriate when it is omitted, when the agent administered has no antifungal activity against the infecting organism, or when its serum concentrations are subtherapeutic.A growing proportion of Candida isolates obtained from blood samples have reduced antifungal susceptibility to fluconazole and other antifungal agents (14, 25). Patients with candidemia caused by Candida strains with high MICs for fluconazole or voriconazole and echinocandins can have a worse prognosis (22-24). Consequently, systematic use of empirical antifungal agents with broad-spectrum in vitro activity has led to considerable increases in the number of adverse events and in the cost of treatment (2).The combination of an increasing number of antifungal-resistant isolates and the cost of the new antifungal agents makes antifungal susceptibility testing a necessity. The reference antifungal susceptibility testing method for yeasts is the Clinical and Laboratory Standards Institute (CLSI; formerly NCCLS) testing standard M27-A3. However, this method requires pure-culture isolates, and results of antifungal susceptibility testing are not available until 48 to 72 h after the isolation of fungi in blood.The Etest performed directly on blood samples may expedite antifungal testing and provide results in 24 h. Our group has previously demonstrated that the Etest performed directly on samples from the lower respiratory tract is a rapid and accurate procedure for antimicrobial susceptibility testing of bacteria in patients with ventilator-associated pneumonia (4, 5). We compared the results of the Etest performed directly on positive blood cultures with yeasts grown in Bactec blood bottles with the results of CLSI M27-A3 in isolates from patients with fungemia and blood samples generated from previously characterized isolates.(This study was partially presented at the 20th Conference of the European Congress of Clinical Microbiology and Infectious Diseases [ECCMID] in Vienna, Austria, 2010 [abstract no. P-838] [13a].)