School furniture match to students' anthropometry in the Gaza Strip.

This study aimed at comparing primary school students' anthropometry to the dimensions of school furniture and determining whether the furniture used matches the students' anthropometry. A sample of 600 male students, whose ages were between 6 and 11 years, from five primary schools in the Gaza Strip governorates participated in the study. Several students' body dimensions were measured. The dimensions measured included elbow-seat height, shoulder height, knee height, popliteal height and buttock-popliteal length. Measurements of the dimensions of the classroom furniture indicated that there was a considerable mismatch between the students' body dimensions and the classroom furniture. The mismatches in seat height, seat depth and desk height occurred for 99% of the students, while the mismatch for the back rest height was only 35%. Two design specifications were proposed in order to decrease the mismatch percentage based on the data obtained. The two proposed designs showed a considerable improvement in the match percentages as compared to the existing design. STATEMENT OF RELEVANCE: Having identified mismatches between the dimensions of the school furniture used in primary schools in the Gaza Strip, two new design specifications are proposed and shown to improve match with the students' anthropometric dimensions. The findings of the study are also an important addition to local knowledge on school children's anthropometry.

Neural network and multiple linear regression to predict school children dimensions for ergonomic school furniture design.

The current study investigates the possibility of obtaining the anthropometric dimensions, critical to school furniture design, without measuring all of them. The study first selects some anthropometric dimensions that are easy to measure. Two methods are then used to check if these easy-to-measure dimensions can predict the dimensions critical to the furniture design. These methods are multiple linear regression and neural networks. Each dimension that is deemed necessary to ergonomically design school furniture is expressed as a function of some other measured anthropometric dimensions. Results show that out of the five dimensions needed for chair design, four can be related to other dimensions that can be measured while children are standing. Therefore, the method suggested here would definitely save time and effort and avoid the difficulty of dealing with students while measuring these dimensions. In general, it was found that neural networks perform better than multiple linear regression in the current study.

Prevalence of low positive anti-HCV antibodies in blood donors: Schistosoma mansoni co-infection and possible role of autoantibodies.

Patients infected with schistosoma frequently show a high seroprevalence of anti-hepatitis C virus (anti-HCV) antibodies. The aim of this study was to find the underlying reason for this phenomenon, and to examine a possible involvement of autoantibodies. Out of 2,400 Egyptian blood donors, 192 (8%) were anti-HCV positive by ELISA. They were 133 males and 59 females with age ranging from 27 to 48 years. According to optical density ratio (ODR) of anti-HCV antibodies, 96 cases were low positive (LP) with ODR (1-2) designated as group I, and 96 were high positive (HP) with ODR (> or =2) (group II). Both groups were examined for quantitative HCV core antigen (HCVcAg), liver function (Albumin, ALT, AST) and anti-Schistosoma mansoni(anti-Sm) IgG. Group I cases were HCVcAg negative with normal liver function tests, and 44 of them were anti-Sm positive. Ninety cases (93.75%) of group II were HCVcAg positive with markedly affected liver function tests and 72 cases were anti-Sm positive. All group I cases were examined for autoimmune markers (ANA, AMA, SMA and LKM). In group I, 33 (75%) of anti-Sm positive cases were positive for one or more of the autoimmune markers examined, while none of anti-Sm negative was positive for any marker with significant difference between the two groups (P < 0.0001). Our results primarily on blood donors indicate that LP anti-HCV frequently represents false-positive reactivity with a possible role of Sm-induced autoantibodies in this phenomenon.

Pityriasis amiantacea: a clinical and etiopathologic study of 85 patients.

BACKGROUND: Studies on pityriasis amiantacea (PA) in the literature are limited and mostly retrospective. We prospectively analyzed the clinical and etiopathologic factors in a large series of PA diagnosed at our department within a defined period (2000-01). METHODS: All PA patients who attended our department were evaluated clinically and underwent bacteriologic, mycologic, and histopathologic examinations. Forty healthy control persons were similarly subjected to bacteriologic and mycologic investigations of their scalp hairs. RESULTS: A total of 85 PA patients were collected and studied. Pathological diagnosis of scalp psoriasis was confirmed in 35.3% of cases. Eczematous features suggesting a diagnosis of seborrheic and atopic dermatitis were detected in 34.2%. Diagnosis of tinea capitis, diagnosed by potassium hydroxide preparation, fungal culture, and periodic-acid Schiff staining, was detected in 12.9% of the PA patients. Staphylococcus isolates were detected in 96.5% of the PA patients compared with 15% in healthy persons as the control (P > 0.00001). CONCLUSIONS: Pityriasis amiantacea represents a particular reaction pattern of the scalp to various inflammatory scalp diseases. The most frequent skin diseases associated with PA are psoriasis and seborrheic dermatitis. It is important to keep the diagnosis of tinea capitis in mind when evaluating PA patients. Staphylococci on the scalp could participate in the pathogenesis of PA.

Genotypes and phylogenetic characterization of hepatitis B and delta viruses in Egypt.

Hepatitis B virus (HBV) and hepatitis D virus (HDV) sequences among HBV carriers from Egypt have not been evaluated sufficiently. The genotypes of HBV isolated from 105 serum samples from Egyptian carriers were determined. Four complete genomes and 11 entire preS1/S2/S genes were sequenced and evaluated. All serum samples were classified into HBV genotype D using serologic and genetic methods. The length of four complete nucleotide sequences was 3,182 bp. In all 15 samples, the common 33 nucleotides (11 amino acids) deletions in the preS1 region specific for HBV genotype D were observed. In the phylogenetic analysis based on the complete nucleotide sequences, all samples were clustered with the HBV isolates reported from previously Western and Mediterranean countries with nucleotide homology ranging from 96.0-98.0%. Of 75 HBsAg positive samples, anti-HDV was found in 15 (20%), and HDV RNA was detected in 9 of 15 (60%). The proportion of the patients with liver disease was higher in HBV carriers of anti-HDV positive with HDV RNA than in HBV carriers of anti-HDV positive without HDV RNA (P < 0.05). In the phylogenetic analysis based on the sequences in nucleotide position 853-1267 of HDV, nine samples were classified into HDV genotype I with the nucleotide homology ranging from 88.3-92.1% (mean; 90.5%) and clustered with HDV strains reported previously from Ethiopia, Somalia, Egypt, and Lebanon. These results indicate that HBV genotype D and HDV genotype I are most prevalent in Egypt, and HDV co-infection in HBV carriers is related to severity of liver disease.

Exponential spread of hepatitis C virus genotype 4a in Egypt.

Hepatitis C virus (HCV) infects >10% of the general population in Egypt, in which intravenous injection with an antimony compound for endemic schistosomiasis in the past has been implicated. To simulate the epidemic history of HCV in Egypt, sera were obtained from 3608 blood donors at 13 governorates in or surrounding the Nile valley during 1999. The prevalence of antibody to HCV (anti-HCV) and genotypes was determined in them, and the molecular evolutionary analysis based on the neutral theory was applied to HCV isolates of genotype 4a, which is outstandingly prevalent in Egypt and indigenous there. Of 3608 sera, 317 (8.8%) were positive for anti-HCV. The molecular evolutionary analysis on 47 HCV genotype 4a isolates of carriers from various districts in Egypt indicated that the spread of HCV-4a would have increased exponentially during the 1940s through 1980 when oral medications became available. In conclusion, the estimated spread time is consistent with the duration of intravenous antimony campaigns in Egypt.

Reliability of hepatitis C virus core antigen assay for detection of viremia in HCV genotypes 1, 2, 3, and 4 infected blood donors: a collaborative study between Japan, Egypt, and Uzbekistan.

Nucleic acid amplification-based methods are used for confirmation of viremia in antibody to hepatitis C virus (anti-HCV)-positive patients. However, this technology is labor intensive, time consuming, requires complex laboratory conditions, and expensive. The aim of this study was to evaluate the sensitivity and specificity of the HCV core antigen (HCVcAg) assay as an alternative approach for confirmation of viremia in HCV-infected subjects with HCV genotype 1-4. Two hundred forty-six asymptomatic HCV RNA- positive donors were enrolled in this study, consisting of 122 blood donors from Egypt (116 with genotype 4, 4 with genotype 1, and 2 with 1 + 4 genotypes), 109 from Japan (85 with genotype 1, and 24 with genotype 2), and 15 from Uzbekistan (all with genotype 3). A total of 234 (95.1%) of 246 RNA-positive specimens were detected by the HCVcAg assay; the sensitivity of HCVcAg assay consisted 93.4, 100, 100, and 94.8% for genotypes 1, 2, 3, and 4, respectively in comparison with RT-PCR assay. The specificity of the assay was confirmed in the absence of the false-positive results among 53 anti-HCV-negative, but anti-Schistosoma mansoni (anti-Sm) positive donors from Egypt. A positive correlation between HCVcAg and HCV RNA concentration levels (r = 0.671, P < 0.05) was observed among specimens with HCV genotype 4. The mean HCVcAg level was significantly lower in specimens with genotype 4 (2,935 fmol/L) comparing to genotypes 1, 2, and 3 (5,034, 4,962, and 4,740 fmol/L, respectively). No specific mutation was found in the core-encoding region of the studied specimens. In conclusion, HCVcAg is shown to be specific, sensitive, and informative qualitative index for HCV viremia in asymptomatic carriers.