NovaSil clay intervention in Ghanaians at high risk for aflatoxicosis: II. Reduction in biomarkers of aflatoxin exposure in blood and urine.

The efficacy of NovaSil clay (NS) to reduce aflatoxin (AF) biomarkers of exposure was evaluated in 656 blood samples and 624 urine samples collected from study participants during a 3-month phase IIa clinical intervention trial in Ghana. NS was delivered before meals via capsules. Serum AFB (1)-albumin adduct was measured by radioimmunoassay and urinary AFM (1) metabolites were quantified by immunoaffinity-high-performance liquid chromatography (HPLC)-fluorescence methods. Levels of AFB (1) -albumin adduct in serum samples collected at baseline and at 1 month were similar (p = 0.2354 and p = 0.3645, respectively) among the placebo (PL), low dose (LD, 1.5 g NS day (-1)), and high dose (HD, 3.0 g NS day (-1)) groups. However, the levels of AFB (1)-albumin adduct at 3 months were significantly decreased in both the LD group (p < 0.0001) and the HD group (p < 0.0001) compared with levels in the PL group. Levels of AFM(1) in urine samples collected at baseline and at 1 month were not statistically different among the three study groups. However, a significant decrease (up to 58%) in the median level of AFM (1) in samples collected at 3 months was found in the HD group when compared with the median level in the PL group (p < 0.0391). In addition, significant effects were found for dose, time, and dose-time interaction with serum AFB(1)-albumin adduct and dose-time interaction with urinary AFM (1) metabolites. The results suggest that capsules containing NS clay can be used to reduce effectively the bioavailability of dietary AF based on a reduction of AF-specific biomarkers.     

用深入的冶金模型预测板坯质量

铸坯的缺陷是由连铸过程中某些参数引起的，通过计算和根据水力学模型试验可以模拟这些参数。这种模拟预测的效果是：需要对板坯末端进行清理的量减少9％，消除由AlN引起的横裂纹，更清楚地了解了结晶器保护渣卷入的情况；同时指出，换钢包后较慢的中间罐的注入速度可减少板坯内的钢包渣夹杂物。     

Effect of topical oral G-CSF on oral mucositis: a randomised placebo-controlled trial

Oral mucositis is a dose-limiting toxicity of intensive chemotherapy. It is caused directly by the cytotoxic effect of chemotherapeutic agents and indirectly by sustained neutropenia. Severe oral mucositis is an important predisposing factor for life-threatening septic complications during aplasia. It also reduces quality of life. At present, no effective causal prophylaxis or treatment against oral mucositis is established. We performed a prospective randomised placebo-controlled trial using topical oral r-metHuG-CSF (filgrastim) in high-grade lymphoma patients treated according to the B-NHL protocol, which contains high-dose methotrexate and causes severe oral mucositis (WHO grades I-IV) in >50% of patients. Between August 1996 and July 1997, a total of 32 chemotherapy cycles were documented in eight patients (four male, four female). Mucosal erythema and ulceration were recorded. All patients assessed their oral pain and impact on swallowing daily, using a subjective scale from no to maximal discomfort (1-10). In addition, oral mucositis was assessed according to the WHO score. Filgrastim was administered in 16 cycles as a viscous mouthrinse (carboxymethylcellulose 2%, oleum citrii) 4 x 120 microg/day from days 10 to 16. Sixteen cycles were given to control patients, of these 14 with placebo, and another two cycles with no treatment. Severe mucositis (WHO grade III/IV) was documented in 21 of 32 cycles (65.5%). A difference of borderline significance was observed for the reduction of maximum severity of oral mucositis between G-CSF vs placebo (P = 0.058), with a reduction of WHO grade IV of 50% (four G-CSF vs eight control). The number of days in hospital was reduced significantly in the G-CSF group (P = 0.02). In conclusion, topical oral G-CSF mouthrinses may be beneficial to reduce oral mucositis.     

The murine Fhit locus: isolation, characterization, and expression in normal and tumor cells

The murine Fhit locus maps near the centromere nu proximal Ptprg locus on mouse chromosome 14. The cDNA sequence and structure are similar to those of the human gene, with exons 5-9 encoding the protein. The predominant mRNA in the tissues and cell lines tested was an alternatively spliced form missing exon 3. Most murine cell lines tested, including lines established from normal mouse embryos and tumors, expressed very low or undetectable levels of Fhit mRNA. Most normal mouse tissues expressed wild-type Fhit mRNA, whereas approximately 40% of murine lung carcinomas expressed wild-type and aberrant Fhit RT-PCR products that lacked various exons. Several tumorigenic mouse cell lines exhibited homozygous deletions of Fhit exons. We conclude that the murine Fhit gene, like its human counterpart, is a target of alterations involved in murine carcinogenesis.     

Concept for diamond 3-D integrated UV sensor

In this investigation we present a novel technology for three-dimensional integration of diamond sensors and actuators. Based on a previously developed technology for the integration of a 3-D CMOS camera stack, in this attempt nano-crystalline diamond layers on silicon are used at the sensor level. The processing steps involve silicon thinning, through-silicon etching and metallization, as well as a soldering process using inter-metallic diffusion. Strong emphasis lies on a low thermal budget process, making the technology suitable for backend processing. The concept is demonstrated, however active CMOS chips are not yet implemented. First electrical measurements of the through-connected UV sensors are presented.     

Subsurface Sensing, Subsurface Aquametry

An attempt is started to define the terms of aquametry and its adjective subsurface. Subsurface Sensing represents a field of scientific research and development character, which is much wider than that of the classical non-destructive material testing in industrial production. It covers the 2 or 3D mapping of distributed parameters, broad application fields, the interactions of waves and beams with matter, signal propagation in media, almost all sensing techniques like radar, optical, acoustic and nuclear sensors as well as the measurements of material properties. Dielectric sensing dominates in the water content determination, i.e. in aquametry. The problems of aquametry are critically commented: Proposals of free and bound water definitions are made. The volume-related water content determination is preferred. The reference method, i.e. oven drying, impedes the development. The calibration or relation to the water content in indirect measurements is discussed. Optimum measuring frequency is treatedas well. Subsurface Aquametry is introduced as a development of Microwave Aquametry and Dielectric Aquametry. Also, dielectric water research is involved. By providing included and excluded examples and accepting the basic features of common Aquametry, the subject is defined with a call for contributions.     

Molecular characterization of high affinity, high capacity clays for the equilibrium sorption of ergotamine

Ergot alkaloids (mycotoxins) produced by Claviceps and Neotyphodium species of fungi may contaminate animal feedstuffs and result in disease in livestock. In this study, diverse phyllosilicate clays and other adsorbent materials, differing in chemical and structural characteristics, were tested for their ability to sorb ergotamine, a prevalent ergot mycotoxin, from acidic solution. Results indicated minimal binding to those sorbents possessing low surface area, cation exchange capacity and inaccessible interlayer regions. Cetyl pyridinium-exchanged montmorillonite (organoclay) exhibited decreased propensity for ergotamine in acidic solution as compared with the unexchanged hydrophilic parent clay. The highest ergotamine sorption was observed with cation exchanged montmorillonite clays; whereas, when collapsed, these same clays sorbed very little ligand. Based on initial binding experiments, calcium and sodium montmorillonite clays were prioritized for further characterization, including: capacity, affinity, and heat (enthalpy) of adsorption. Computer models of energy-minimized ergotamine isomers and clay were used to illustrate possible mechanisms of ergot alkaloid sorption at interlayer sites. Additional studies are warranted to assess the stability of ergot alkaloid/clay complexes under alkaline conditions to further understand the mechanism of adsorption.     

Nasopharyngeal carriage of community-acquired, antibiotic-resistant Streptococcus pneumoniae in a Zambian paediatric population

The present study was conducted to examine the response of amoeboid microglial cells in the postnatal rat brain to colchicine administration. One-day-old postnatal rats were given intraperitoneal injections of colchicine and sacrificed at 7, 14 and 21 days of age. In rats killed at 7 days age, the number of OX-42, OX-18 and ED1 positive amoeboid microglial cells was considerably reduced when compared with the control rats. At 14 and 21 days, the number of cells immunoreactive with the above antibodies was comparable to that of the control rats. The intensity of the immunoreaction with the various antibodies was also comparable in colchicine injected and control rats. When rhodamine isothiocyanate (RhIC) was administered, amoeboid microglial cells emitted a bright fluorescence in control rats as well as in colchicine-injected rats, although in the latter, the number of RhIC labelled cells was considerably reduced. With the antibody bromodeoxyuridine a large number of stained cells were observed in the control rats. On the other hand, occasional labelled cells were recognized in colchicine-injected rats. Apoptotic amoeboid microglial cells were observed in 4-day-old colchicine-injected rats. At the electron microscopic level, amoeboid microglial cells in colchicine-injected rats killed at 7 days of age showed a large number of phagosomes in their cytoplasm compared with the corresponding control rats. At 14 and 21 days, in colchicine-injected and control rats, amoeboid microglial cells did not display any noticeable differences. It is concluded from the present study that colchicine suppresses the number of amoeboid microglial cells, and that this may be attributed to the antimitotic effect of the drug as well as apoptosis induced by it; the phagocytic activity, however, was not affected. The cells returned to their normal population and morphological features once the drug was discontinued, indicating the reversible nature of the drug effect.     

Long-term survival of Streptococcus pneumoniae at room temperature on Dorset egg medium

Forty-five isolates of Streptococcus pneumoniae were inoculated on Dorset egg and supplemented Columbia agar base media, incubated overnight at 37 degrees C, and then kept at room temperature (RT; 21 degrees C) or 4 degrees C. Long-term viability was best at RT for both media, with all isolates remaining viable on Dorset egg medium for 44 days; viability was 90 and 57% on Columbia agar base medium after 7 and 30 days. We recommend the use of Dorset egg medium for the maintenance of pneumococci at RT.