Chronic effects of low lead levels on sperm quality, gonadotropins and testosterone in albino rats

The current study evaluates the impact of low or moderate levels of lead acetate (PbAc) on sperm parameters, gonadotropins (FSH, LH) and testosterone. Adult albino wistar male rats were allocated to five groups and given 0%, 0.025%, 0.05%, 0.1% and 0.3% PbAc in distilled drinking water for 24 weeks.There was no change in body weight gain and in absolute or relative weight of testes, epididymides and seminal vesicles. The ventral prostate weight was decreased in groups exposed to 0.05%, 0.1% and 0.3% PbAc without statistically significant differences.Sperm velocity was decreased in all treated groups while reduction of sperm motility was observed in rats exposed to 0.05%, 0.1% and 0.3% PbAc without statistically significant differences compared to the control group. However, there was a significant increase greater than 100% in the total percentage of abnormal sperm in groups treated with 0.1% (p<0.01) and 0.3% PbAc (p<0.05).The frequency of dead sperm was significantly increased only in the 0.3% PbAc group (p<0.01). Significant increases in frequencies of amorphous head sperm (p<0.01) and abnormal tails (p<0.01) were found in the group exposed to 0.1% PbAc, while the frequency of neck abnormalities was increased in the high-lead-exposed group (p<0.01).The levels of LH and FSH were not significantly affected after lead treatment and significant increase in serum testosterone level was noted only in animals administered 0.05% PbAc (p<0.01).In conclusion, our results reveal that some sperm parameters were altered at low or moderate lead concentrations with no obvious alteration of hypothalamic–pituitary function. The increase of testosterone level observed suggests that lead may target testicular function.     

Distribution of HLA-B27 and its alleles in patients with reactive arthritis and with ankylosing spondylitis in Tunisia

The purpose of the present study is to investigate the frequency of HLA-B27 and its alleles in reactive arthritis (ReA) and in ankylosing spondylitis (AS) in Tunisia. HLA-B27 alleles were typed by PCR amplification with sequence-specific primers. We studied 17 patients with ReA associated with urethritis or with gastrointestinal infection; 42 HLA-B27-positive patients with AS and 100 healthy controls. Eleven ReA patients (67.7%) were HLA-B27 positive. There was an increased frequencies of HLA-B27 (P = 7.76 × 10⁻¹², OR = 59.30) and a moderate increase of HLA-B51 (P = 0.015; OR = 4.91) alleles in ReA patients when compared with healthy controls. Four B27 subtypes were identified: B*2702, 05, 09 and B*2712. The distribution of these alleles in the ReA patients was 37.5% for B*2702 and B*2705. Only these two subtypes were detected in 18 (42.8%) and 24 (57.1%), respectively, of the AS patients. B*2709 and B*2712 were relatively rare in ReA patients and were identified in one case each. Our results showed a restricted number of HLA-B27 subtypes associated with ReA and AS. B*2702 and 2705 were common in ReA and AS patients.     

Purification and partial characterization of paralytic shellfish poison-binding protein from Acanthocardia tuberculatum.

A paralytic shellfish poison-binding protein (PSPBP) was purified 16.6-fold from the foot of the Moroccan cockles Acanthocardia tuberculatum. Using affinity chromatography, 2.5mg of PSPBP showing homogeneity on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was obtained from 93 mg of crude extract. The purified PSPBP exhibits a specific activity of about 2.78 mU/mg proteins and has estimated molecular weight of 181 kDa. Observation of a single band equivalent to 88 kDa on SDS-PAGE under reducing conditions suggested it to be a homodimer. The optimal temperature and pH for the purified PSPBP were respectively 30 degrees C and 7.0.     

Cyanobacteria and their toxins in treated-water storage reservoirs in Abha city, Saudi Arabia.

Occurrence of toxic cyanobacteria in drinking and recreational waters poses human health at risk as they can release potent toxins into the water. In the present study, open and covered treated-water storage reservoirs as well as their relevant tap waters in Abha city, Saudi Arabia, were surveyed for the presence of cyanobacteria and their toxins. The results revealed the contamination of most open reservoir and tap waters by algae and cyanobacteria, with an abundance of toxigenic species of cyanobacteria. Depending on the results of the Limulus amebocyte lysate (LAL) assay and enzyme linked immunosorbent assay (ELISA), endotoxins and microcystins (MCYSTs) were found in most open reservoir and tap waters at concentrations up to 32EUml(-1) and 0.3mugml(-1), respectively. The extracts of axenic cultures of most cyanobacterial species isolated from these reservoirs showed activity to LAL assay, with large endotoxin amounts obtained in Calothrix parietina (490EUg(-1)) and Phormidium tenue (210EUg(-1)). Based on ELISA and HPLC analysis for these extracts, only C. parietina can produce MCYSTs (202mugg(-1)) with a profile consisting of MCYST-RR and -LR. This study suggests that open treated-water storage reservoirs should be covered to prevent the presence of cyanobacteria and their toxins in such drinking and recreational waters.     

Optical coherence tomography and vessel diameter changes after intravitreal bevacizumab in diabetic macular oedema

Purpose: To assess the effect of intravitreal bevacizumab on diabetic macular oedema (DMO) and retinal vessel calibres. Methods: We performed a consecutive case series study in which 10 consecutive eyes with diffuse DMO, two of which had not previously been treated, received an intravitreal injection of bevacizumab 1 mg, which was followed by two more injections at 6‐week intervals. Fundus photography and optical coherence tomography (OCT) were carried out at baseline immediately before injection and at 1, 2.5 and 4 months after the first injection. Outcome measures were best corrected visual acuity (BCVA) in Early Treatment Diabetic Retinopathy Study letters, macular volume, foveal subfield thickness and vessel diameter measurement. Results: Intravitreal administration of bevacizumab was followed by a mean increase in BCVA of 7.3 ± 17 (mean ± standard deviation) letters between baseline and month 4, which was 1 month after the last injection (p < 0.0001). This was accompanied by a reduction in mean macular volume from 9.90 ± 1.9 mm³ to 8.96 ± 2.4 mm³ (p = 0.002) and in foveal subfield thickness from 447 ± 117 μm to 388 ± 117 μm (p = 0.03). Two eyes with early proliferative diabetic retinopathy lost all signs of proliferation without any evidence of fibrosis. Although there was a trend towards vasoconstriction, the changes in vessel diameters (arteries and veins) after 4 months of intravitreal Avastin injection were not statistically significant (p = 0.9 and p = 0.17, respectively). Foveal thickness in non‐injected fellow eyes with DMO changed from 428 ± 153 μm at baseline to 383 ± 151 μm at 4 months (p = 0.1), which did not reach statistical significance. Conclusions: Intravitreal bevacizumab 1 mg every 6 weeks was followed by a moderate reduction in DMO without normalization of foveal and macular thickness. Our observations suggest that a larger study where patients are examined sooner after injection is needed to elucidate the potential relationship between changes in retinal vessel diameters and thickness changes in DMO.