Genetic variability of hepatitis B virus in Uruguay: D/F, A/F genotype recombinants

Hepatitis B virus (HBV) infection is a serious global health problem. Approximately 2 billion people worldwide have been infected, and approximately 350 million individuals currently suffer from HBV-induced chronic liver infection, which causes 600,000 deaths annually from chronic hepatitis, cirrhosis and hepatocellular carcinoma. HBV is classified in eight genotypes (A-H), and two more have been proposed (I-J). In this paper, complete genome sequences of nine Uruguayan HBV are reported. Five samples belong to genotype F1b and one to genotype A2. Three HBV recombinants were detected: A1/F1b, A2/F1b and D3/F1b. The following mutations were detected: a G1896A substitution, a 33-nucleotide deletion from position 2896 to 2928 in the Pre-S1 region involving Pre-S1 residues 3-13, a 33-nt deletion in the Pre-S1 region involving nt 2913-2945 and Pre-S1 residues 9-19. More F genotypes strains than expected were detected in this study, supporting the hypothesis that there are more people of indigenous origin than declared in our population. Also, one third of the samples analyzed were recombinants. This cannot be explained by the low HBV prevalence in Uruguay, but a high HBV infection rate in drug addicts and dialysis patients could act in favor of multiple-genotype HBV infections that could lead to recombination.

Electronically addressable nanomechanical switching of i-motif DNA origami assembled on basal plane HOPG

Here, a pH-induced nanomechanical switching of i-motif structures incorporated into DNA origami bound onto cysteamine-modified basal plane HOPG was electronically addressed, demonstrating for the first time the electrochemical read-out of the nanomechanics of DNA origami.

Aerobic co-treatment of landfill leachate and domestic wastewater - are slowly biodegradable organics removed or simply diluted?

This study investigated the co-treatment of landfill leachate/domestic wastewater in bench-scale activated sludge (AS) reactors to determine whether the slowly biodegradable organic matter (SBOM) was removed rather than diluted. The AS reactors were loaded with mixtures of raw leachate and leachate that was pretreated by air stripping. The tested volumetric ratios were 0%, 0.2%, 2% and 5%. For all of the tested conditions, the reactors performed better when pretreated leachate was used rather than raw leachate, and the best volumetric ratio was 2%. The following removals were obtained: 97% for the biochemical oxygen demand (BOD5,20), 79% for total suspended solids, 77% for dissolved organic carbon and 84% for soluble chemical oxygen demand. Most of the pretreated leachate SBOM (65%) was removed rather than diluted or adsorbed into the sludge, as confirmed by Fourier transform infrared (FTIR) spectroscopy analyses.

Inflammatory muscle pain is dependent on the activation of kinin B₁ and B₂ receptors and intracellular kinase pathways

BACKGROUND AND PURPOSE

B(1) and B(2) kinin receptors are involved in pain transmission but they may have different roles in the muscle pain induced by intense exercise or inflammation. We investigated the contribution of each of these receptors, and the intracellular pathways involved, in the initial development and maintenance of the muscle pain associated with inflammation-induced tissue damage.

EXPERIMENTAL APPROACH

Mechanical hyperalgesia was measured using the Randall-Selitto apparatus after injecting 5% formalin solution into the gastrocnemius muscle in mice treated with selective antagonists for B(1) or B(2) receptors. The expression of kinin receptors and cytokines and the activation of intracellular kinases were monitored by real-time PCR and immunohistochemistry.

KEY RESULTS

The i.m. injection of formalin induced an overexpression of B(1) and B(2) receptors. This overexpression was associated with the mechanical hyperalgesia induced by formalin because treatment with B(1) receptor antagonists (des-Arg(9) [Leu(8)]-BK, DALBK, and SSR240612) or B(2) receptor antagonists (HOE 140 and FR173657) prevented the hyperalgesia. Formalin increased myeloperoxidase activity, and up-regulated TNF-α, IL-1β and IL-6 in gastrocnemius. Myeloperoxidase activity and TNF-α mRNA expression were inhibited by either DALBK or HOE 140, whereas IL-6 was inhibited only by HOE 140. The hyperalgesia induced by i.m. formalin was dependent on the activation of intracellular MAPKs p38, JNK and PKC.

CONCLUSIONS AND IMPLICATIONS

Inflammatory muscle pain involves a cascade of events that is dependent on the activation of PKC, p38 and JNK, and the synthesis of IL-1β, TNF-α and IL-6 associated with the up-regulation of both B(1) and B(2) kinin receptors.

First WHO International Reference Panel containing hepatitis B virus genotypes A-G for assays of the viral DNA

BACKGROUND

WHO International Standards (IS) are provided for the calibration and validation of diagnostic and screening assays, e.g. for hepatitis B virus (HBV). HBV forms numerous subgenotypes and the current IS for HBV DNA reflects subgenotype A2.

OBJECTIVE

A reference panel with the most prevalent subgenotypes should facilitate evaluation of genotype-specific detection efficiencies.

STUDY DESIGN

215 HBV positive plasma samples collected worldwide were characterized for HBV markers and sequenced. Fifteen subgenotype A1, A2, B2, B4, C2, D1, D3, E, F2 and G samples were selected for the panel. The lyophilized samples were tested in parallel with the IS in an international collaborative study with 16 laboratories using 13 different nucleic acid amplification techniques (NATs).

RESULTS

Eight of 13 NAT had a HBV DNA detection efficiency which was independent of the genotype and consistent with the IS, while with five assays, certain deviations were noted, particularly with genotype F which was under quantitated or even missed by three assays. The panel was accepted by the WHO as the "1st WHO International Reference Panel for HBV Genotypes for HBV NAT-Based Assays".

CONCLUSIONS

The evaluation of HBV DNA assays should include many different genotypes. The WHO Reference Panel is universally available for manufacturers of HBV DNA assays, diagnostic laboratories and control authorities to facilitate standardized validation of HBV genotype specific detection efficiency of both diagnostic (quantitative and qualitative) and screening NAT assays.

A new laser Doppler flowmeter prototype for depth dependent monitoring of skin microcirculation

Laser Doppler flowmetry (LDF) is now commonly used in clinical research to monitor microvascular blood flow. However, the dependence of the LDF signal on the microvascular architecture is still unknown. That is why we propose a new laser Doppler flowmeter for depth dependent monitoring of skin microvascular perfusion. This new laser Doppler flowmeter combines for the first time, in a device, several wavelengths and different spaced detection optical fibres. The calibration of the new apparatus is herein presented together with in vivo validation. Two in vivo validation tests are performed. In the first test, signals collected in the ventral side of the forearm are analyzed; in the second test, signals collected in the ventral side of the forearm are compared with signals collected in the hand palm. There are good indicators that show that different wavelengths and fibre distances probe different skin perfusion layers. However, multiple scattering may affect the results, namely the ones obtained with the larger fibre distance. To clearly understand the wavelength effect in LDF measurements, other tests have to be performed.

[Laparoscopic simple prostatectomy (adenomectomy): experience in 59 consecutive patients]

OBJECTIVE

Laparoscopic adenomectomy 150 is a minimally invasive alternative to open surgery in large prostates. Our aim is to discuss our series of 59 patients treated by means of laparoscopic adenomectomy with precise vascular control.

MATERIALS AND METHODS

Between June 2003 and June 2006, a total of 59 patients with a mean age of 65.5 years (51 to 82), underwent laparoscopic extraperitoneal adenomectomy. All the patients had a history of lower urinary tract symptoms (LUTS) and benign prostatic hyperplasia (BPH). The mean International Prostate Symptom Score (IPSS) was 20 points (16-22). The information was collected prospectively in a database. The analysis was performed subsequently.

RESULTS

All 59 adenomas were completely removed laparoscopically without conversion to open surgery. The mean preoperative prostate volume by ultrasound was 108.5 cc (75-150). The average operating time was 123 minutes (90-180). The mean loss of blood was 415 ml (50-1500) and 4 patients (14.8%) required a blood transfusion. Two (7.4%) of the patients presented perioperative complications. The mean hospital stay and the bladder catheterization time were 3.5 (2-7) and 4.2 (3-7) days respectively.

CONCLUSIONS

Laparoscopic extraperitoneal simple prostatectomy is an effective procedure for the treatment of large prostatic adenomas. There seems to be less perioperative morbidity and, in our experience, this technique seems to be feasible and reproducible; however, its learning curve is a complicated matter to deal with.

[Laparoscopic radical cystectomy with extracorporeal creation of a "Y" shaped orthotopic ileal neobladder using non-reabsorbable mechanical suture (Fontana)]

INTRODUCTION

We describe the technique and present the preliminary results of the laparoscopic radical cystectomy technique with the extracorporeal creation of a "y" shaped ileal orthotopic neobladder using non-absorbable mechanical suture (Fontana).

MATERIALS AND METHOD

We describe the technique step by step and we present a series of 15 patients that underwent this surgery between November 2005 and August 2009, with special emphasis on the duration of the surgery, urinary diversion time, intraoperative and postoperative complications, daytime and night time continence and the frequency of postoperative micturition.

RESULTS

The mean follow-up of the series was 24 months (6-32). The mean duration of surgery was 280 (range 210-345) minutes and the mean urinary diversion time was 54.5 (range 40-75) minutes. There were no intraoperative complications and the average hospitalization time was 7 (range 5-15) days. During the follow-up, there were 5 late postoperative complications, 2 cases of urinary infection with good response to antibiotic treatment and 3 uretero-neovesical anastomosis strictures, which were treated with percutaneous balloon dilation, with a good functional result. No lithiasis was found in the neobladder. Complete daytime continence was obtained in 13/14 patients (92.9%) and complete night time continence in 6/14 (42.9%). One patient (6.7%) required clean intermittent self-catheterization as the patient did not micturate spontaneously.

CONCLUSIONS

The creation of a "Y" shaped ileal orthotopic neobladder using non-absorbable mechanical suture is a feasible, fast and safe technique and it provides promising functional results. Further follow-up is required to determine its long-term results.

[A pilot study on a quality improvement plan with systematic nutritional screening in patients admitted to a regional hospital]

OBJECTIVE

A pilot study to assess the feasibility of implementing a hospital protocol for systematic nutritional screening of admitted patients.

METHOD

Descriptive cross-sectional study. Patients admitted to the Orthopedic Surgery Department of the Regional Hospital of Alcañiz were systematically included within the first 48 hours of hospitalization, from February to September of 2007. The screening methods used were the Nutritional Risk Index (NRI), the CONUT Nutritional Control system, and an indicator based on SENPE recommendations. The need for nutritional support was defined as the presence of any of the following instances: moderate to severe hyponutrition according to the NRI or CONUT methods, or hyponutrition according to the adapted SENPE recommendations.

RESULTS

36.4% of the patients assessed need nutritional support. The rate of hyponutrition according to CONUT is 13.6%, by SENPE criteria is 27.3%, and by the NRI 29.5%. The inter-method agreement is statistically significant and clinically acceptable: Kappa between NRI and CONUT 0.547, between NRI and SENPE 0.609, and between CONUT and SENPE 0.593.

CONCLUSIONS

The implementation of a structured protocol for collecting the anthropometrical and biochemical parameters implicating a multidisciplinary hospital team enables identifying those patients in whom appropriate nutritional support may improve their prognosis during hospital stay.