Incidence and characteristics of HBV reactivation in hematological malignant patients in south Egypt

AIM:To investigate characteristics of hepatitis B virus(HBV)implicated in HBV reactivation in patients with hematological malignancies receiving immunosuppressive therapy.METHODS:Serum samples were collected from 53 patients with hematological malignancies negative for hepatitis B surface antigen(HBsAg)before the start of and throughout the chemotherapy course.HBV reactivation was diagnosed when the HBsAg status changed from negative to positive after the initiation of chemotherapy and/or when HBV DNA was detected by realtime detection polymerase chain reaction(RTD-PCR).For detecting the serological markers of HBV infection,HBsAg as well as antibodies to the core antigen(antiHBc)and to the surface antigen were measured in the sera by CEIA.Nucleic acids were extracted from sera,and HBV DNA sequences spanning the S gene were amplified by RTD-PCR.The extracted DNA was further subjected to PCR to amplify the complete genome as well as the specific genomic sequences bearing the enhancerⅡ/core promoter/pre-core/core regions(nt1628-2364).Amplicons were sequenced directly.RESULTS:Thirty-five(66%)of the 53 HBsAg-negative patients were found to be negative serologically for antiHBc,and the remaining 18(34%)patients were positive for anti-HBc.Five of the 53(9.4%)patients with hematologic malignancies experienced HBV reactivation.Genotype D1 was detected in all five patients.Four types of mutant strains were detected in the S gene product of HBV strains and were isolated from 3 patients with HBV reactivation:T/S120,L143,and I126.HBV DNA was detected in the pretreatment HBsAg-negative samples in one of the five patients with HBV reactivation.In this patient,sequences encompassing the HBV full genome obtained from sera before the start of chemotherapy and at the time of de novo HBV hepatitis were detected and it showed 100%homology.Furthermore,in the phylogenetic tree,the sequences were clustered together,thereby indicating that this patient developed reactivation from an occult HBV infection.CONCLUSION:Past infection with     

Corneal aberrations after microincision cataract surgery

PURPOSE: To study the effect of microincision cataract surgery (MICS) on the optical quality of the cornea, characterized in terms of Seidel aberrations. SETTING: Instituto Oftalmológico de Alicante, Vissum, Alicante, Spain. METHODS: This study comprised 25 eyes of 25 patients with nuclear or corticonuclear cataract of grade 2+ to 4+ (Lens Opacities Classification System III). Microincision cataract surgery was performed using low ultrasound power through a 1.6 to 1.8 mm clear corneal incision placed on the axis of the positive corneal meridian. An Acri.Smart 48S intraocular lens (Acri.Tec) was implanted in all eyes. Seidel aberration root-mean-square (RMS) values were obtained with a 6.0 mm aperture using the CSO topographer (Costruzione Strumenti Oftalmici) preoperatively and 1 and 3 months postoperatively. RESULTS: The total RMS after MICS decreased slightly from a mean of 2.15 microm +/- 2.51 (SD) preoperatively to 1.96 +/- 2.01 microm postoperatively; the decrease was not statistically significant (P = 1.00). The difference between the corneal astigmatism from preoperatively (-0.80 +/- 0.76 diopter [D]) to postoperatively (-0.63 +/- 0.62 D) was not statistically significant (P = 1.00) nor were the differences in Seidel aberrations, coma, or higher-order aberrations. CONCLUSION: Microincision cataract surgery did not degrade the optical quality of the cornea or induce a modification in corneal astigmatism, including the axis.     

Microstructure and Mechanical Properties of Friction Stir Welded 2205 Duplex Stainless Steel Butt Joints

Friction stir welding (FSW) as a solid-state process is an excellent candidate for high softening temperature materials welding; however, extending the tool life is required to make the process cost-effective. This work investigates the use of a high pin to shoulder ratio (65%) tungsten carbide (WC) tool for friction stir welding of 5 mm thick 2205 DSS to extend the tool life of this low-cost tool material. In addition, the effect of FSW parameters in terms of rotational rates, travel speeds, and downward forces on the microstructural features and mechanical properties of the welded joints were investigated. Characterization in terms of visual inspection, macro and microstructures, hardness, and tensile testing was conducted. The obtained results indicated that the combined rotational rate, travel speed, and downward force parameters govern the production of defect-free joints. The 2205 DSS friction stir welds show an enhancement in hardness compared to the base material. The stir zone showed a significantly refined grain structure of ferrite and austenite with the reduction in the average grain size from 8.8 µm and 13.3 µm for the base material to 2.71 µm and 2.24 µm, respectively. Moreover, this joint showed higher yield strength and ultimate tensile strength compared to the DSS as-received material.     

Malaria and red cell genetic defects

The study of inherited RBC resistance to malaria has increased our knowledge of the biochemistry and physiology of the host-parasite interaction and suggested potential sites for therapeutic intervention. Discovery by Jensen and Trager of the in vitro culture system for P falciparum has facilitated research in this area. Known RBC defects may affect invasion, growth, or merozoite liberation (Fig 1). Significant advances made in understanding mechanisms underlying protection against malaria should not obscure the fact that the data are far from complete. More knowledge is needed about the influence of the erythrocyte cytoskeleton on invasion and growth of parasites as well as the potential role of phospholipids, erythrocyte enzymes other than G6PD, or other metabolic products. Application of DNA analysis and recombinant technology may have an increasing impact on study of the interaction of RBC defects with malarial parasites.     

New hepatitis B virus mutant form in a blood donor that is undetectable in several hepatitis B surface antigen screening assays

BACKGROUND: Envelope mutant forms of hepatitis B virus (HBV), impairing HBV antibody recognition, have been reported with mutations in single or multiple sites of the hepatitis B surface antigen (HBsAg) group- specific "a" determinant. Blood donors infected with such an HBsAg mutant form of HBV may escape detection by HBsAg screening assays and therefore may affect the safety of the blood supply. CASE REPORT: A repeat blood donor became HBsAg-reactive in an enzyme immunoassay. Confirmatory testing yielded negative results for HBsAg in a radioimmunoassay and in four enzyme immunoassays used in blood donor screening. The specificity of the HBsAg reactivity in the first enzyme immunoassay was confirmed by HBsAg neutralization with antibody to HBsAg. Additional HBV confirmatory test results were positive for antibody to hepatitis B core antigen and antibody to hepatitis B e antigen; negative for antibody to HBsAg and for hepatitis B e antigen; and positive for HBV DNA. DNA sequence analysis of the "a" determinant region of HBsAg revealed amino acid substitutions from Q (Gln) to R (Arg) at codon 129 and from M (Met) to T (Thr) at codon 133. CONCLUSION: This case illustrates the presence of HBsAg mutant forms of HBV in a West European blood donor population that were undetected by several HBsAg screening assays. Adaptation of HBsAg screening is indicated to overcome deficiencies in sensitivity in detecting HBsAg mutant forms of HBV. Screening for antibody to hepatitis B core antigen or HBV DNA may also detect blood donors infected with HBsAg mutant forms of HBV     

Diet and body composition of preterm infants

There have been few systematic studies of the effects of energy and protein intake on the body composition of preterm infants. Analysis of published studies suggests a roughly inverse relation between energy stored per gram of weight gain (a measure of the fatness of new tissues) and the ratio of protein to energy in the preterm infant's diet. At least within a certain range of energy and protein intakes, a higher protein diet promotes leaner body composition. Studies of the effects of varying the dietary ratio of carbohydrate to fat in preterm infants have shown reduced rates of carbon dioxide production with high-fat diets, fed by either the parenteral or enteral route. The little information available suggests no clear effect of varying the carbohydrate-to-fat ratio on body composition. The mineral content of the body can be influenced by diet. Insufficient intakes of calcium and phosphorus reduce the bone mineral content and thus the whole-body content of these minerals.     

Development of the hypodysplastic kidney: contribution of antenatal US diagnosis

Two cases of fetal perirenal uriniferous pseudocyst were diagnosed in utero with ultrasound studies. The perirenal collections resolved spontaneously in utero. Follow-up examination showed growth impairment of the affected kidney. At birth, no renal function was demonstrated in one case and only slight function in the other case. Pathologic examination showed a highly dysplastic kidney with extravasated urine in the case in which surgery was performed. Some hypodysplastic kidneys apparently result from acute in utero obstruction with secondary pyelocalyceal rupture. Renal dysplasia could render the kidney more vulnerable to such phenomena.     

皮肤幼年性血管瘤的处理

过去对脉管疾病的描述往往将血管瘤和脉管畸形相混淆，从而导致不恰当的治疗及医学文献记录的矛盾。Mulliken和Glowacki系统描述了血管瘤和脉管畸形的差别，认为血管瘤是真正的肿瘤，在组织学上表现为细胞增殖。在治疗方面文献报道也存在不同，有人认为血管瘤可以完全自行消退，而部分文献却主张对病变进行干预。最近．对血管瘤自然病程研究增多，并对血管瘤是观察还是干预的选择进行了讨论，设计了安全有效的治疗方案。该文分2部分，第1部分结合新近文献，综述血管瘤的诊断及其自然病程，并与旧的文献作了比较。第2部分介绍了血管瘤是治疗还是观察的原则，推荐治疗方法，并着重论述了外科技术。