Sister chromatid exchanges and ion release in patients wearing fracture fixation devices

The quantification of sister chromatid exchange (SCE) during mitosis is a useful index for evaluating genotoxic effects in subjects occupationally or incidentally exposed to potentially toxic substances. The authors investigated the hypothesis that ions released by corrosion from prosthetic components of fracture fixation devices are associated with change in SCE incidence. In the present study, ten patients with implants were examined, and fifteen subjects with no implants were used as controls. SCE and high frequency cell (HFC) numbers were evaluated in circulating lymphocytes. In addition, nickel (Ni) and chromium (Cr) ion values in the serum were measured because, after iron, these metals are major components of stainless steel. A significant increase in SCE numbers was observed in patients compared to the control population (4.9 +/- 1.3 vs. 3.5 +/- 1.4). Ni concentration was 1.71 +/- 1.49 ng/mL in patients and 0.72 +/- 0.52 ng/mL in control subjects; Cr concentration was, respectively, 1.01 +/- 0.77 ng/mL and 0.19 +/- 0. 27 ng/mL. The increase of serum Cr and Ni was statistically significant. No correlation was found between the increased Cr concentrations and SCE number while Cr ion levels were found to be significantly correlated to HFC. An inverse correlation between Ni level and SCE numbers was observed. Our findings suggest that Cr release by stainless steel implants could have a genotoxic effect; thus it would be useful to carefully monitor implanted subjects with regard to serum ion dosage, SCE analysis, and HFC evaluation. In any case, it would be appropriate to remove the implant when fracture fixation is reached.     

Anti-HIV effects of chloroquine: inhibition of viral particle glycosylation and synergism with protease inhibitors

OBJECTIVE: We tested the effects of chloroquine (CQ) on glycosylation of HIV particles and in combination with protease inhibitors (PIs) on HIV replication and on P-glycoprotein (P-gp)/multidrug resistance protein-1 (MRP1). DESIGN: CD4 cell lines were infected with laboratory strains and peripheral blood mononuclear cells were infected with primary isolates for evaluation of the anti-HIV effects. Peripheral blood lymphocytes were evaluated for of P-gp and MRP1 functions. METHODS: HIV replication was assessed by enzyme-linked immunosorbent assay. HIV glycosylation was measured by metabolic labeling of viral particles with [H] glucosamine. Synergism was tested using isobolograms. P-gp and MRP1 functions were assayed using rhodamine 123 (Rh123) and carboxyfluorescein (CF) efflux assays, respectively. RESULTS: CQ alone inhibited HIV replication and glycosylation in a dose-dependent manner. In combination with indinavir (IDV), ritonavir, or saquinavir (SQV), CQ had a synergistic effect at concentrations found in plasma of subjects receiving malaria prophylaxis. CQ decreased the 50% effective concentration of IDV in primary isolates from Africa and restored the response to IDV or SQV in 3 PI-resistant isolates. CQ increased the block of Rh123 and CF efflux activity exerted by PIs. CONCLUSION: The inhibitory effects of CQ on HIV glycosylation are associated with synergistic effects in combination with PIs. The CQ/PI combination exerts combined inhibitory effects on P-gp and MRP1 function.     

Biologic effects of surface roughness and fluorhydroxyapatite coating on osteointegration in external fixation systems: an in vivo experimental study

The concomitant influence of surface roughness and fluorhydroxyapatite (FHA) coating of titanium (Ti) implants on bone response was investigated. For this purpose, titanium screw-shaped implants with a lower degree (Y371) and a higher degree (TiPore300) of surface roughness, coated with FHA and uncoated, were transversally inserted into the diaphyses of sheep tibiae for 12 weeks. Four sheep received Y371 (group A) and Y371 + FHA (group B) screws and four sheep received TiPore300 (group C) and TiPore300 + FHA (group D) screws. For each type of material, the morphology and microstructure of implant-facing bone were evaluated. The host bone of each tibia was used as a control. In all groups the bone tissue did not reach a complete maturation. The higher degree of roughness, perhaps due to an excessive irregularity of the surface, induced the worst osteointegration: a fibrous tissue layer between screw and new bone tissue was often present. Nevertheless, as viewed by XRD, no crystallographic change of the apatite lattice was observed in any of the implants. In contrast, the microhardness value, an index of bone mineralization, was higher in the uncoated screws and decreased progressively in the following order: group C > group A > group B > group D. The association of plasma spraying with roughness treatment constitutes a complex system that seems to interfere with bone mineralization. A chemical change of the surface, perhaps with more Ti release or more coating degradation, could be responsible for such impairment. The authors emphasize the necessity for simultaneous evaluation of surface topography and chemistry as well as an improvement in plasma-spraying and post-processing techniques and in standard procedures for materials characterization.     

Identification of MEN1 gene mutations in sporadic carcinoid tumors of the lung

Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.      

止泻散敷脐治疗婴幼儿腹泻100例

0　引言　腹泻乃小儿最常见病 ,尤以 2岁以下婴幼儿最为常见 .年龄越小 ,发病率越高 ,且多在夏、秋季发病 .小儿患病后惧怕打针 ,服药以及输液 ,给治疗带来一些困难 . 12 a来 ,我们用自拟的止泻散敷脐治疗婴幼儿泄泻 ,效果良好 .1　对象和方法1.1　对象　 1998- 0 6 / 1999- 10婴幼儿腹泻发病高峰期门诊病例 10 0 (男 6 6 ,女 34 )例 ,年龄 2月龄～ 5岁 .肠炎 5 8例 ,单纯消化不良 42例 . 6 7例曾多次治疗 ,33例初诊 .凡接受治疗之患儿 ,一律停止用其他药物 .1.2　方法　药物组成 :川椒 12 g,干姜 12 g,小茴香 12 g,白芷 2 0 g,吴茱萸 5 g,…     

Epidemiology of rotavirus diarrhea in Egyptian children and implications for disease control.

Reliable epidemiologic data are essential for formulating effective policy to control rotavirus disease through immunization. The objective of this study was to describe the epidemiology of rotavirus diarrhea in a population-based cohort of children under 3 years of age residing in Abu Homos, Egypt, in 1995-1996. Rotavirus diarrhea incidence rates (episodes per person-year) were 0.13 for infants aged <6 months, 0.61 for those aged 6-11 months, 0.17 for those aged 12-23 months, and 0.15 for those aged 24-35 months. Fifty-six percent of children with rotavirus diarrhea had clinical dehydration; 90% of rotavirus diarrheal episodes occurred between July and November. In infants under 1 year of age, receipt of breast milk was associated with a lower incidence of rotavirus diarrhea. No other sociodemographic or environmental factor was found to be significantly associated with rotavirus diarrhea. Of 46 rotavirus isolates with strains identified, 41 (89%) were G serotypes 1 and 2. Rotavirus diarrhea was a major cause of morbidity in this cohort. Promotion of breastfeeding may exert a protective effect in young infants in this setting, but improvements in water and sanitation are unlikely to be effective preventive measures. The use of effective immunization against rotavirus in early infancy should be considered a public health priority.     

Incidence of apnoea and bradycardia in preterm infants following DTPw and Hib immunization: A prospective study

Objective: To evaluate the incidence and severity of apnoea and bradycardia in hospitalized preterm infants following immunization at 2 months of age, and identify risk factors.
Methodology: A prospective study of 98 preterm infants, of gestational age 24–31 weeks, immunized at approximately 2 months post natal age with diphtheria-tetanus-whole cell pertussis vaccine (DTP_w) in the neonatal intensive care unit (NICU) at King George V Hospital Sydney. Half the infants also received Haemophilus influenzae type b conjugate vaccine (Hib) simultaneously. All infants were monitored for apnoea and bradycardia in the 24 h periods pre- and post immunization.
Results: Only one infant had apnoea and/or bradycardia pre-immunization compared with 17 post immunization. For 12 infants these events were brief, self-limiting and not associated with desaturations (oxygen saturation <90%). However, for five infants (30%) these events were associated with oxygen desaturation and two of these infants required supplemental oxygen. The group that had apnoea and/or bradycardia and the group that did not were not significantly different in terms of gestational age, birth weight and other variables. Infants who received Hib together with DTP_w were less likely to have apnoea and/or bradycardia than those given DTP_w alone.
Conclusion: When considering immunization for preterm infants, the benefits of early immunization must be balanced against the risk of apnoea and bradycardia. We recommend that the cardio-respiratory function of hospitalized infants born at less than 31 weeks gestation be monitored for 48 h post immunization.     

Impedance-pH Monitoring for Diagnosis of Reflux Disease: New Perspectives

Heartburn is the most specific symptom of gastroesophageal reflux disease (GERD). In clinical practice, heartburn relief by a proton pump inhibitor (PPI) trial does suffice to confirm GERD. However, an objective diagnosis of GERD is required before anti-reflux endoscopic or surgical interventions, independently from PPI response. Thus, since normal findings at upper endoscopy are detected in the majority of patients with heartburn, reflux monitoring is often required. When traditional catheter-based or wireless pH tests are used, reflux episodes are conventionally identified by pH drops below 4.0 units. Combined impedance-pH monitoring has the advantage to provide a comprehensive assessment of both physical and chemical properties of refluxate and the distinction between acid and weakly acidic refluxes, both proven to cause heartburn. Unfortunately, the conventional impedance-pH parameters, namely acid exposure time and number of reflux events, are characterized by suboptimal diagnostic sensitivity, and the reliability of symptom–reflux association indexes remains questionable. Therefore, novel impedance parameters, namely the post-reflux swallow-induced peristaltic wave (PSPW) index and the mean nocturnal baseline impedance (MNBI), have recently been proposed in order to achieve a better diagnostic yield. In fact, they proved to be highly accurate in distinguishing reflux-related from reflux-unrelated heartburn, off- as well as on-PPI therapy. Currently, manual review of impedance-pH tracings is needed because of the modest accuracy of available software tools for automated analysis. PSPW index and MNBI are highly applicable and reproducible, and their calculation requires a few additional minutes during the manual review of impedance-pH tracings. So far, we believe that PSPW index and MNBI are ready for prime time and should become part of the standard analysis of impedance-pH tracings for GERD diagnosis in patients with endoscopy-negative heartburn.