Multiscale analysis of hydrogen-induced softening in f.c.c. nickel single crystals oriented for multiple-slips: elastic screening effect.

Hydrogen-deformation interactions and their role in plasticity are well accepted as key features in understanding hydrogen embrittlement. In order to understand the nature of the hydrogen-induced softening process in f.c.c. metals, a substantial effort was made in this study to determine the effect of hydrogen on the tensile stress-strain behavior of nickel single crystal oriented for multiple-slips. It was clearly established that the hydrogen softening process was the result of a shielding of the elastic interactions at different scales. Hydrogen-induced softening was then formalized by a screening factor S of 0.8 ± 0.05 for 7 wppm of hydrogen, which can be incorporated into standard dislocation theory processes. The amplitude of softening suggests that the shielding process is mainly responsible for the stress softening through the formation of vacancy clusters, rather than a direct impact of hydrogen. This effect is expected to be of major importance when revisiting the impact of hydrogen on the processes causing damage to the structural alloys used in engineering.

An international comparison of risk factors between two regions with distinct differences in asthma prevalence

BACKGROUND AND PURPOSE: Investigation of the geographic variation in asthma prevalence can improve our understanding of asthma etiology and management. The purpose of our investigation was to compare the prevalence of asthma and wheeze among adolescents living in two distinct international regions and to investigate reasons for observed differences. METHODS: A cross-sectional survey of 13-14 year olds was completed in Saskatoon, Canada (n = 1200) and Skopje, Republic of Macedonia (n = 3026), as part of the International Study of Asthma and Allergies in Childhood (ISAAC) Phase 3 study. Surveys were self-completed by students following the ISAAC protocol. Multiple logistic regression models were used to investigate associations with reports of asthma and current wheeze. A mediation analysis was then completed. RESULTS: Asthma prevalence was much higher in Saskatoon than Skopje (21.3% vs. 1.7%) as was the prevalence of current wheeze (28.2% vs. 8.8%). Higher paracetamol (acetaminophen) use was a consistent risk factor for asthma and wheeze in both locations and showed dose-response relationships. In both countries, paracetamol use and physical activity mediated some of the association for both asthma and wheeze. In Saskatoon, among those with current wheeze, 42.6% reported ever having a diagnosis of asthma compared to 10.2% among Skopje adolescents. CONCLUSIONS: The results suggest that the variation in risk factors between the two locations may explain some of the differences in the prevalence of asthma and wheeze between these two study sites. However, diagnostic labeling patterns should not be ruled out as another potential explanatory factor

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Effects of the incorporation of cantaloupe pulp in yogurt: Physicochemical, phytochemical and rheological properties.

The therapeutic effects of cantaloupe are of great interest for the development of functional foods such as yogurt. In this study a new dairy product has been formulated by enriching natural yogurt with fruit cantaloupe (yogurt with cantaloupe puree, yogurt with dry cantaloupe and yogurt with dry cantaloupe and cantaloupe puree). Thus, composition (moisture, ash, lipids, proteins), including amino acid contents, lactic flora as well as rheological (viscoelasticity, viscosity) property of cantaloupe yogurt and natural yogurt is assessed. In addition, pH value, water holding capacity and antioxidant activity (reducing power) are measured over refrigerated storage time. There are significant differences between natural yogurt and cantaloupe yogurt in almost all parameters. The results show that the pH decreases during the storage period and the antioxidant activity as well as the water holding capacity are more remarkable in the yogurt with dry cantaloupe at the 14th and the 28th day of storage, respectively. The addition of cantaloupe in natural yogurt ameliorates the load of lactic flora and modifies the rheological property of the new products. The results of the current study show that the addition of cantaloupe to yogurt significantly improved its quality.

[Cerebral and pulmonary nocardiosis to Nocardia abscessus in an immunocompetent Algerian patient]. / Nocardiose cérébrale et pulmonaire à Nocardia abscessus chez un patient algérien immunocompétent.

Nocardial brain abscess is often occurring in immunocompromised patients. It is uncommon in immunocompetent individuals. Here, the authors describe a case of cerebral and pulmonary nocardiosis mimicking a metastatic tumor in an apparently health 40-year-old Algerian male. The patient presented multiple brain abscess revealed by inaugural epileptic seizure. He was afebrile and presented with left hemiparesis. Staging imaging showed a nodular lung lesion in the apical segment of the right lower lobe. The patient underwent double craniotomy for resection of the lesion. Culture of the resected specimen isolated Nocardia abscessus. The patient was initially started on intravenous trimethoprim-sulfamethoxazole and intravenous amikacine. He was switched to oral trimethoprim-sulfamethoxazole. He finished seven months of antibiotic therapy with a good clinical response. Imaging revealed reduction in the brain abscess and a complete resolution of the lung lesion. Cotrimoxazole was stopped after twelve months of therapy. After two years, the health status of our patient improves day after day. He is however regularly under medical supervision for control exams.

An international comparison of risk factors between two regions with distinct differences in asthma prevalence.

BACKGROUND AND PURPOSE: Investigation of the geographic variation in asthma prevalence can improve our understanding of asthma etiology and management. The purpose of our investigation was to compare the prevalence of asthma and wheeze among adolescents living in two distinct international regions and to investigate reasons for observed differences. METHODS: A cross-sectional survey of 13-14 year olds was completed in Saskatoon, Canada (n=1200) and Skopje, Republic of Macedonia (n=3026), as part of the International Study of Asthma and Allergies in Childhood (ISAAC) Phase 3 study. Surveys were self-completed by students following the ISAAC protocol. Multiple logistic regression models were used to investigate associations with reports of asthma and current wheeze. A mediation analysis was then completed. RESULTS: Asthma prevalence was much higher in Saskatoon than Skopje (21.3% vs. 1.7%) as was the prevalence of current wheeze (28.2% vs. 8.8%). Higher paracetamol (acetaminophen) use was a consistent risk factor for asthma and wheeze in both locations and showed dose-response relationships. In both countries, paracetamol use and physical activity mediated some of the association for both asthma and wheeze. In Saskatoon, among those with current wheeze, 42.6% reported ever having a diagnosis of asthma compared to 10.2% among Skopje adolescents. CONCLUSIONS: The results suggest that the variation in risk factors between the two locations may explain some of the differences in the prevalence of asthma and wheeze between these two study sites. However, diagnostic labeling patterns should not be ruled out as another potential explanatory factor.

Modelling the effect of temperature, water activity and carbon dioxide on the growth of Aspergillus niger and Alternaria alternata isolated from fresh date fruit.

AIMS: To quantify and model the combined effects of temperature (T) (10-40°C), water activity (aw ) (0·993-0·818) and CO2 concentration (9·4-55·1%, v/v) on the growth rate of Aspergillus niger and Alternaria alternata that cause spoilage during the storage and packaging of dates. METHODS AND RESULTS: The effects of environmental factors were studied using the γ-concept. Cardinal models were used to quantify the effect of studied environmental factors on the growth rates. Firstly, the cardinal parameters were estimated independently from experiments carried out on potato dextrose agar using a monofactorial design. Secondly, model performance evaluation was conducted on pasteurized date paste. The boundary between growth and no-growth was predicted using a deterministic approach. Aspergillus niger displayed a faster growth rate and higher tolerance to low aw than Al. alternata, which in turn proved more resistant to CO2 concentration. Minimal cardinal parameters of T and aw were lower than those reported in the literature. CONCLUSIONS: The combination of the aw and CO2 effects significantly affected As. niger and Al. alternata growth. The γ-concept model overestimated growth rates, however, it is optimistic and provides somewhat conservative predictions. SIGNIFICANCE AND IMPACT OF THE STUDY: The developed model provides a decision support tool for the choice of the date fruit conservation mode (refrigeration, drying, modified atmospheric packaging or their combination) using T, aw and CO2 as environmental factors.

A metabolite-profiling approach allows the identification of new compounds from Pistacia lentiscus leaves.

Pistacia lentiscus L., commonly known as Mastic tree or lentisk, is a Mediterranean evergreen shrub widely used in traditional medicine to treat such diseases as eczema, diarrhoea, and throat infections. Furthermore, other properties are currently attributed to P. lentiscus, such as antioxidant capacity, hepatoprotective action, and anti-inflammatory effects. High-performance liquid chromatography with diode array coupled to electrospray ionization mass spectrometry (HPLC-ESI-QTOF-MS) was used for the comprehensive characterization of methanol extract from P. lentiscus leaves. After the optimisation of the HPLC-ESI-QTOF-MS method and the use of the negative ionization mode, 46 different compounds were identified, 20 of which were tentatively characterized for the first time in P. Lentiscus leaves. The majority of the compounds were quantified. Flavonoids, phenolic acids and their derivatives were the most abundant compounds, those with the highest concentrations being myricetin glycoside (6216.13 mg/kg of plant), catechin (3354.78 mg/kg of plant), ß-glucogallin (2214.461 mg/kg of plant), and quercitrin gallate (1160 mg/kg of plant). The importance of the knowledge of plants is increasing and our study may help in the future to formulate nutraceutical preparations and will provide the basis for new investigation into activities of the various compounds found in P. lentiscus.

Delayed diagnosis of fetal and neonatal alloimmune thrombocytopenia: a cause of perinatal mortality and morbidity.

OBJECTIVE: To evaluate the rate and consequences of a late or missed diagnosis of fetal and neonatal alloimmune thrombocytopenia (FNAIT). DESIGN: Retrospective analysis of prospectively collected data of a national cohort. SETTING: National referral centre for fetal therapy in the Netherlands. POPULATION: Twenty-six women with pregnancies complicated by FNAIT and at least one previous pregnancy with a thrombocytopenic child. METHODS: Retrospective analysis of data from our electronic FNAIT database. In a consecutive cohort managed between July 2008 and July 2010, timing of first diagnosis of FNAIT was correlated to severity and outcome in the subsequent pregnancies. MAIN OUTCOME MEASURES: Occurrence of delayed diagnosis of FNAIT, and possibly associated intracranial haemorrhage (ICH). RESULTS: In four of 26 pregnancies, timely diagnostic testing for FNAIT was not performed despite fetal or neonatal thrombocytopenia or ICH. Down syndrome, dysmaturity and birth trauma were perceived to be the cause of the thrombocytopenia/ICH. In two of these four subsequent, untreated pregnancies, severe fetal ICH occurred. The other 22 women were treated for FNAIT using intravenous immunoglobulin, all children are alive and well. CONCLUSIONS: All neonates with thrombocytopenia at birth should be evaluated for FNAIT. Missing this diagnosis can have severe consequences for subsequent pregnancies.

Spatial and temporal variability of water quality of an urbanized river in Algeria: the case of Soummam Wadi.

Spatial and temporal variations of water quality were investigated at four sites of an urbanized river in Algeria during a period of low water level in the years 2002, 2003, and 2004. Physical-chemical parameters (temperature, pH, conductivity, dissolved oxygen, suspended matter, chemical oxygen demand [COD], and 5-day biochemical oxygen demand [BOD5]) were measured. The Soummam River showed a strong pollutant load, which was organic in origin and expressed by mean concentrations in suspended matter, COD and BOD5 exceeding 150, 100, and 50 mg/L, respectively. The spatial variation highlighted two areas--(1) the first one gathers the upstream and central sites of the river, and (2) the second one is found downstream. In the downstream area, the pollutant load is almost twice as high as in the first area and, the percent saturation of dissolved oxygen is relatively weak (< 55%). This load is the result of the significant volume of urban and industrial emissions in the river, the high temperature during low-water-level periods, and flood events, which occurred just before the period of low water level. The Soummam River was classified according to the criteria of appreciation of surface water and was found to be extremely polluted. This work is one of the first studies on the quality of rivers in Algeria. This research will be useful as a first step for future works in North Africa and will add to knowledge on the water quality in the Mediterranean Basin.

Removal turbidity and separation of heavy metals using electrocoagulation-electroflotation technique A case study.

The electrocoagulation (EC) process was developed to overcome the drawbacks of conventional wastewater treatment technologies. This process is very effective in removing organic pollutants including dyestuff wastewater and allows for the reduction of sludge generation. The purposes of this study were to investigate the effects of the operating parameters, such as pH, initial concentration (C(0)), duration of treatment (t), current density (j), interelectrode distance (d) and conductivity (kappa) on a synthetic wastewater in the batch electrocoagulation-electroflotation (EF) process. The optimal operating conditions were determined and applied to a textile wastewater and separation of some heavy metals. Initially a batch-type EC-EF reactor was operated at various current densities (11.55, 18.6, 35.94, 56.64, 74.07 and 91.5mA/cm(2)) and various interelectrode distance (1, 2 and 3cm). For solutions with 300mg/L of silica gel, high turbidity removal (89.54%) was obtained without any coagulants when the current density was 11.55mA/cm(2), initial pH was 7.6, conductivity was 2.1mS/cm, duration of treatment was 10min and interelectrode distance was 1cm. The application of the optimal operating parameters on a textile wastewater showed a high removal efficiency for various items: suspended solid (SS) 86.5%, turbidity 81.56%, biological oxygen demand (BOD(5)) 83%, chemical oxygen demand (COD) 68%, and color over 92.5%. During the EC process under these conditions, we have studied the separation of some heavy metal ions such as iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), lead (Pb) and cadmium (Cd) with different initial concentrations in the range of 50-600mg/L and initial pH between 7.5 and 7.8. This allowed us to show that the kinetics of electrocoagulation-electroflotation is very quick (<15min), and the removal rate reaches 95%.

Chronic renal failure in Iranian children.

We investigated chronic renal failure (CRF) in 166 Iranian children (95 boys and 71 girls) from July 1991 to June 1999. The mean age at onset of CRF was 7.9+/-4.5 years. The most common cause of CRF was congenital urological malformations (78 cases). The second most common cause of CRF was hereditary nephropathy (21%). Glomerular diseases accounted for only 10% of children who later went on to develop renal failure. High rates of cystinosis and primary hyperoxaluria were seen, and these elevated rates could be due to a high prevalence of parental consanguinity. Eighty-six patients required renal replacement therapy, of whom the majority underwent hemodialysis. The prevalence of primary reflux as a cause of CRF was high compared with reports from western countries. Earlier diagnosis and management of urinary tract infections in this group could reduce the prevalence of reflux as a cause of CRF in this population.

Loss of STAT1 expression confers resistance to IFN-gamma-induced apoptosis in ME180 cells.

Interferon gamma (IFN-gamma) induces apoptosis in many tumor cell lines and sensitizes tumor cells to apoptosis by tumor necrosis factor family members. IFN-gamma induces the expression of many early response genes such as interferon regulatory factor-1 (IRF-1) by activation of signal transducer and activator of transcription (STAT) factor proteins. We found that ME180 cells became resistant to IFN-gamma-induced cell death after 4-5 passages in culture. These resistant cells were characterized by a loss of STAT1 expression and a loss of inducible IRF-1 expression. We describe for the first time the emergence of a STAT1-deficient ME180 cell line.

Proteolytic cleavage of ras GTPase-activating protein during apoptosis.

p120-ras GTPase-activating protein (rasGAP) associates with Ras and negatively regulates Ras signaling by stimulating the intrinsic rate of Ras GTPase activity. rasGAP also associates with other cellular signaling proteins which suggest that rasGAP may play a role in coordinating other signal transduction pathways. Disruption of rasGAP in vivo results in extensive apoptosis. Fas-mediated apoptosis results in the activation of caspases that cleave cellular substrates which are important for maintaining cytoplasmic and nuclear integrity. We show here that rasGAP is proteolytically cleaved by caspases early in Fas-induced apoptosis of Jurkat cells. rasGAP was also cleaved by DNA-damaging chemotherapeutic agents and TNF-related apoptosis inducing ligand (TRAIL), also known as Apo2L. Based on the size of the products generated by cleavage of deletion mutants of rasGAP we predict that cleavage of rasGAP occurs in the hydrophobic region and between the SH2(2) and ras-p21 interacting domain which would leave an intact ras-p21 interacting domain. Interestingly, cleavage of rasGAP in vitro enhanced rasGAP hydrolysis activity. Our results demonstrate that diverse apoptotic stimuli cause caspase-mediated cleavage of rasGAP early in apoptosis.

Dexamethasone inhibits lung epithelial cell apoptosis induced by IFN-gamma and Fas.

Lung epithelium plays a central role in modulation of the inflammatory response and in lung repair. Airway epithelial cells are targets in asthma, viral infection, acute lung injury, and fibrotic lung disease. Activated T lymphocytes release cytokines such as interferon-gamma (IFN-gamma) that can cooperate with apoptotic signaling pathways such as the Fas-APO-1 pathway to induce apoptosis of damaged epithelial cells. We report that IFN-gamma alone and in combination with activation of the Fas pathway induced apoptosis in A549 lung epithelial cells. Interestingly, the corticosteroid dexamethasone was the most potent inhibitor of IFN-gamma- and IFN-gamma plus anti-Fas-induced apoptosis. IFN-gamma induced expression of an effector of apoptosis, the cysteine protease interleukin-1 beta-converting enzyme, in A549 cells. Dexamethasone, in contrast, induced expression of an inhibitor of apoptosis, human inhibitor of apoptosis (hIAP-1), also known as cIAP2. We suggest that the inhibition of epithelial cell apoptosis by corticosteroids may be one mechanism by which they suppress the inflammatory response.

Lactation amenorrhea in Saudi women.

STUDY OBJECTIVE: The study aimed to investigate some aspects of breast feeding, namely-lactation amenorrhea, the average interval between pregnancies, and the extent of knowledge that an average Saudi woman has about breast feeding. DESIGN: This was a cross sectional study in which a pretested questionnaire was used to collect the information. SETTING: The study was conducted in the Taif area between January and April of 1990. Seventy nine primary health care centres participated. PARTICIPANTS: Altogether 1019 of 2400 women contacted who agreed to participate and met the criteria were studied. Eligible subjects were defined as Saudi women, between 16 and 40 years old, who came with their infants for vaccination, and had delivered between one week and 12 months previously. Each mother had at least one other child. MEASUREMENT AND MAIN RESULT: At birth, the percentage of infants who were initially breast fed was 98% but within three days of delivery over two thirds (68.9%) of the mothers gave other supplementary liquids to their infants. At the time of interview more than half (55.1%) of mothers had lactation amenorrhea. The mean (SD) lactation amenorrhea period and birth interval were 5.95 (5) and 26.8 (14.1) months, respectively. Mothers obtained information on breast feeding mainly from their doctors and television. Within families, husbands had the primary role in encouraging their wives to breast feed, followed by the mother and then by the mother in law. It was found that a high percentage (94.2%) of women had breast fed their previous child. CONCLUSION: The lack of adequate information on breast feeding and the short interval between births are local problems which should be considered by the health authorities.

Breast-feeding patterns in Saudi Arabia.

A survey was conducted on 1019 mothers in 79 primary health care centers in Saudi Arabia to determine the patterns of breast feeding. A large percentage of mothers (98%) had breastfed their infants at birth. This rate dropped to 96.5% during the first week of life. There were 635 (64.1%) mothers who started to breastfeed their babies within 6 hours of delivery. Over two-thirds (68.9%) of mothers gave supplemental liquids to infants during the first 3 days of their life. More than half fed their infants on demand rather than on schedule. A high proportion (94.4%) breastfed at night, with 88.1% feeding their infants more than once. There was no significant relationship between the duration of suckling and the mother's age or work status (p 0.05). However, a significant relationship (p 0.001) was found between the duration of suckling and the mother's literacy. More than three-quarters of mothers slept in the same bed with their infants or in the same room. A large percentage of women initiated breast feeding; however, many introduced a supplement too early, a practice that should be discouraged.

Effects of vitamin A status on cellular retinoic acid-binding protein in rat skin and testes.

Cellular retinoic acid-binding protein levels were determined in the skin and testes of normal and retinol-deficient rats. All-trans [3H]retinoic acid (1.1 TBq/mmol) was used to titrate the specific binding sites in tissue cytosol preparations. Scatchard plot analyses were used to determine the concentration of cellular retinoic acid-binding protein and its binding affinity (Kd) for all-trans-retinoic acid. In normal rat skin the concentration of cellular retinoic acid-binding protein was 3317 +/- 924 (SD) fmol/mg protein and the Kd was 1.98 +/- 1.0 x 10(-9) mol/l. In retinol-deficient rat skin the concentration of cellular retinoic acid-binding protein was 2584 +/- 1205 fmol/mg protein and the Kd was 3.30 +/- 3.4 x 10(-9) mol/l. In the normal rat testes the concentration of cellular retinoic acid-binding protein was 2965 +/- 1187 fmol/mg protein and the Kd was 2.30 +/- 2.1 x 10(-9) mol/l. In retinol-deficient rat testes the concentration of cellular retinoic acid-binding protein was 2439 +/- 383 fmol/mg protein and the Kd was 0.3 +/- 0.2 x 10(-9) mol/l. These findings indicate that there are no significant differences in the levels of cellular retinoic acid-binding protein between normal and deficient rat skin and testes (p greater than 0.1, by Wilcoxon rank sum test). We therefore conclude that the level of cellular retinoic acid-binding protein in skin and testes may not be controlled by the availability of vitamin A.

[Safety of donors, quality of products, how much to reduce the quantity of citrate]. / Sécurité des donneurs, qualité des produits jusqu'où diminuer la quantité de citrate.

We examined 1,053 blood samples from 48 donors, for the effect of gradual reduction of citrate. We observed that: 1--Platelet count does not show any significant variation between 1/8 to 1/18 ratio. 2--In 13.3% of the cases, platelet clumping starts at 1/18 ratio. 3--There was no significant variation of the thrombin plasma level between 1/8 to 1/16 ratio (by measuring thrombin/ATIII complex). Our results show clearly that we can reduce the citrate ratio to 1/14 without expecting any adverse effect. Therefore we designated 1/14 as the security ratio. Parallel to this we also found that the average level +/- SD of ionized calcium is 100 +/- 10 muMol at 1/14 ratio.