Assessment of coliphage surrogates for testing drinking water treatment devices.

Test protocols have been developed by the United States Environmental Protection Agency (USEPA) and the World Health Organization (WHO) to test water treatment devices/systems that are used at the individual and home levels to ensure the removal of waterborne viruses. The goal of this study was to assess if coliphage surrogates could be used in this testing in place of the currently required use of animal or human enteric viruses. Five different coliphages (MS-2, PRD1, ΦX-174, Qß, and fr) were compared to the removal of poliovirus type 1 (LSc-2ab) by eight different water treatment devices/systems using a general case and a challenge case (high organic load, dissolved solids, and turbidity) test water as defined by the USEPA. The performance of the units was rated as a pass/fail based on a 4 log removal/inactivation of the viruses. In all cases, a failure or a pass of the units/system for poliovirus also corresponded to a pass/fail by all of the coliphages. In summary, in using pass/fail criteria as recommended under USEPA guidelines for testing water treatment device/systems, the use of coliphages should be considered as an alternative to reduce cost and time of testing such devices/systems.

Molecular cloning and immunogenicity evaluation of rotavirus structural proteins as candidate vaccine.

The middle capsid protein of rotavirus, VP6, constitutes approximately 51% of the virion by weight. The high degree of identity (>87-99%) in the primary amino acid sequences of VP6 proteins from mammalian rotaviruses suggests VP6-based vaccines could potentially provide heterotypic protection. For this reason, significant effort has been directed toward producing recombinant rotavirus VP6 vaccines. We have cloned and expressed 155bp of the VP6 most frequent in Egyptian rotavirus sewage isolates, encoding the VP6 protein in the pET30b vector having an apparent molecular mass of 12.5kDa. The recombinant VP6 expressed by the transformants was detected by SDS-PAGE analysis. Rabbits immunized with the recombinant rotavirus expressed VP6 elicited VP6-specific IgG antibodies that provided significant reductions in the infectious units of the Egyptian rotavirus sewage isolate and human reference rotavirus Wa strain in vitro assay.

Characterization of NS3 protease from an Egyptian HCV genotype 4a isolate.

The role of the NS3 protease in HCV replication was demonstrated by the ability of a protease inhibitor cocktail (10 microg/ml) to abolish the induced cytopathic effect in RAW macrophages upon infection with Egyptian sera. The HCV protease gene was amplified from Egyptian sera by nested PCR and cloned downstream of the CMV promotor in a mammalian expression plasmid, which was then used to transform bacteria. Colonies carrying the gene in the correct orientation were subjected to large-scale plasmid purification followed by sequencing. Phylogenetic comparison of the sequence obtained with published sequences from different genotypes confirmed that our sequence belongs to genotype 4a. Of the other genotypes, the most closely related ones were from genotype 1. Multiple alignments of protease peptides showed that the catalytic triads and binding residues for substrate, Zn2+ and the NS4 cofactor are conserved among different isolates, including ours, and confirmed the closer homology between NS3 of genotypes 4 and 1. The HCV-protease-encoding construct was successfully transcribed in both mammalian cells and mice. Mouse antibodies produced against the protease-encoding-construct detected the 18-kDa enzyme in lysates of cells transfected with the construct by Western blotting, and in the media of infected cells by ELISA.

Failure of puberty in Egyptian beta thalassemic patients: experience in north east region - Dakahlia province.

BACKGROUND: Endocrine complications in thalassemia major (TM) are classically considered to be the result of iron deposition in the endocrine glands. Hypogonadotropic hypogonadism, which still remains the commonest endocrinopathy in patients with TM, has been proven to be the result of hemosiderosis of the gonadotroph cells of the pituitary gland. THE AIM OF THE STUDY: To evaluate the prevalence of delayed puberty and hypogonadotropic hypogonadism in transfusion-dependent patients with beta-TM. PATIENT AND METHODS: Growth and sexual development of 40 patients with TM (20 males, 20 females) aged 12-22 years were evaluated. Thirty healthy individuals aged 12-20 years served as a control group. The following parameters were measured in every patient: age, sex, height, weight, body mass index (BMI) and Tanner's pubertal staging. For all patients, the following investigations were done: ophthalmological evaluation, audiograms, skeletal survey, echocardiography, serum ferritin, liver function tests, hepatitis profile, serum calcium, phosphorus and blood sugar. Thyroid, parathyroid hormones, serum follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T) and estradiol (E2) hormone were also measured. RESULTS: Failure of puberty was present in 80% of boys and 75% of girls aged 12-22 years. Gonadotropin insufficiency was found in most of the patients with lack of puberty. Arrested puberty was noted in five boys (25%) and six girls (30%). Ten girls (50%) did not menstruate, two (10%) had oligomenorrhea, one (5%) had irregular menstrual cycles and two (10%) developed secondary amenorrhea. Using univariate analyses and stepwise logistic regression analysis after adjustment for confounding factors, serum ferritin at the time of the study was identified as an independent risk factor for hypogonadotropic hypogonadism, with an odds ratio of 28.40 (95% confidence interval 3.25-245.15), P = 0.003 with a B value of 3.24 (standard error, 1.12). CONCLUSIONS: We conclude that failure of puberty is common in our thalassemic patients which necessitates newer protocols of treatment, correct blood transfusion and chelation therapy.