Gain-saturated one-pump fiber optical parametric amplifiers in presence of longitudinal dispersion fluctuations.

In this paper, we investigate the impact of longitudinal dispersion fluctuations of the optical fiber on the gain spectrum and the saturation behavior of one-pump fiber-optical parametric amplifiers (1-P FOPAs). The gain spectra and the saturation curves of 1-P FOPAs are simulated by solving the coupled amplitude equations numerically and taking into account the dispersion fluctuations as a stochastic process with a given standard deviation and correlation length. Results show that the shape and the level of the gain spectrum and also the saturation power of 1-P FOPAs are considerably changed in the presence of dispersion fluctuations in comparison with the case when dispersion fluctuations are ignored. This feature is also totally different compared with the small-signal gain spectrum of the FOPA in the presence of dispersion fluctuations. Moreover, the value of the change in the gain and the saturation power depends strongly on the fluctuation parameters, i.e., the standard deviation and the correlation length.

The Impact of a Low Glycemic Index Diet on Inflammatory Markers and Serum Adiponectin Concentration in Adolescent Overweight and Obese Girls: A Randomized Clinical Trial.

Although the effects of dietary glycemic index (GI) on insulin resistance are well documented in adults, the complex interaction among glucose intolerance, inflammatory markers, and adipokine concentration has not been well studied, especially among adolescents. We investigated the effect of a low glycemic index (LGI) diet on insulin concentration, fasting blood sugar (FBS), inflammatory markers, and serum adiponectin concentration among healthy obese/overweight adolescent females. In this parallel randomized clinical trial, 2 different diets, an LGI diet and a healthy nutritional recommendation diet (HNRD) with similar macronutrient composition were prescribed to 50 obese and overweight adolescent girls with the same pubertal status. Biochemical markers FBS, serum insulin concentration, high sensitivity C-reactive protein (hs-CRP), interleukin 6 (IL-6), and adiponectin were measured before and after a 10 week intervention. Using an intention-to-treat analysis, data from 50 subjects were analyzed. According to a dietary assessment, GI in the LGI group was 43.22±0.54. While the mean for FBS, serum insulin concentration, the homeostasis model assessment (HOMA), the quantitative insulin sensitivity check index (QUICKI), and adiponectin concentration did not differ significantly within each group, the average hs-CRP and IL-6 decreased significantly in the LGI diet group after the 10 week intervention (p=0.009 and p=0.001; respectively). Comparing percent changes, we found a marginally significant decrease in hs-CRP in the LGI group compared with the HNRD group after adjusting for confounders. Compliance with an LGI diet may have favorable effect on inflammation among overweight and obese adolescent girls.

Effectiveness of cold therapy in reducing pain, trismus, and oedema after impacted mandibular third molar surgery: a randomized, self-controlled, observer-blind, split-mouth clinical trial.

Cold therapy is a conventional and widely used modality for reducing pain, trismus, and oedema after dentoalveolar surgeries. However, information reported in the literature on its effectiveness is insufficient and controversial. This study was performed to evaluate the effect of local cold application in reducing pain, trismus, and swelling after impacted mandibular third molar surgery. Thirty patients (seven males and 23 females) with bilateral symmetrical mandibular impacted third molars were enrolled in this randomized, self-controlled, observer-blind clinical trial. The patients were aged between 18 and 30 years. After surgical removal of the tooth on one side (intervention), ice pack therapy was given for 24h after surgery; for the other side (control), no cold therapy was given. The time interval between the two surgeries was at least 4 weeks. The amount of pain, trismus, and facial swelling was measured on days 2 and 7 postoperative, and patient satisfaction with the cold therapy vs. no cold therapy was assessed. The amount of pain, trismus, and facial swelling, and the extent of patient satisfaction were not significantly different between the intervention and control sides. Cold therapy had no beneficial effects on postoperative sequelae after impacted mandibular third molar surgery.

Effects of Carum carvi L. (Caraway) extract and essential oil on TNBS-induced colitis in rats.

Carum carvi L. (Apiaceae family) or caraway is a common household plant grown around the world including Iran. Caraway fruits are used as flavoring agent in foods and beverages, and have various traditional uses in ethnomedicine. Anti-inflammatory, spasmolytic, antimicrobial, antioxidant, carminative and immunomodulatory properties of caraway suggest that it might exert beneficial effects on inflammatory bowel disease (IBD). Therefore, this study was carried out to investigate the effects of caraway hydroalcoholic extract (CHE) and its essential oil (CEO) in an immunological model of colitis in rats induced by trinitrobenzene sulfonic acid (TNBS). Different doses of CHE (100, 200, 400 mg/kg) and CEO (100, 200, 400 µl/kg) were administered orally (p.o.) and also doses of CHE (100, 400 mg/kg) and CEO (100, 400 µl/kg) were given intraperitoneally (i.p.) to the separate groups of male Wistar rats (n=6). Administration of the doses started 6 h after induction of colitis and continued daily for 5 consecutive days. Wet colon weight/length ratio was measured and tissue damage scores as well as indices of colitis were evaluated both macroscopically and histopathologically. CHE and CEO at all doses tested were effective in reducing colon tissue lesions and colitis indices and the efficacy was nearly the same when different doses of plant fractions were administered p.o. or i.p. Administration of prednisolone (p.o., 4 mg/kg), Asacol® (mesalazine microgranules, p.o., 100 mg/kg) and hydrocortisone acetate (i.p., 20 mg/kg) as references were effective in reducing colon tissue injures as well. These data suggest that caraway fractions are both effective and possess anti-colitic activity irrespective of the dose and route of administration.

Molecular epidemiology of cryptosporidiosis in Iranian children, tehran, iran.

BACKGROUND: Cryptosporidium is a worldwide protozoan parasite and one of the most common causes of infection and diarrhea in humans and cattle. The aim of the present study was determination of subtypes of Cryptosporidium among children with diarrhea in Tehran by sequence analysis of the highly polymorphic 60-kDa glycoprotein (GP60) gene. METHODS: Fecal samples were collected from 794 diarrheic children. Initial identification of Cryptosporidium was carried out on stool samples by Ziehl-Neelsen acid-fast staining method. DNA was extracted from positive microscopically samples and Cryptosporidium genotypes and subtypes were determined, accordingly. RESULTS: Out of 794 collected samples, 19 (2.40%) were positive for Cryptosporidium oocysts. Sequences analysis of GP60 gene showed that 17 (89.47%) of the positive isolates were Cryptosporidium parvum and 2 (10.52%) were C. hominis. All subtypes of C. parvum isolates belonged to allele families IIa (6/17) and IId (11/17). The most common allele in all 17 isolates belonged to IId A20G1a (41.18%). A22G1 (IF) subtype was detected in two C. hominis isolates of the children. CONCLUSION: The predominancy of C. parvum species (specially, IId A20G1a subtype) in current study underlines the importance of zoonotic Cryptosporidium transmission in Iran.

Socio-demographic Factors Associated with Body Mass Index of Female Adolescent Students in Semnan City, Iran.

Malnutrition among adolescents is not only an important health problem but also an economic development problem in Iran and other developing countries. The home environment is found to be related to the development of malnutrition in children. Information on this relationship is important to identify the target risk groups for nutritional intervention. The objective of this study was to determine the association between socio-demographics with BMI status in high school adolescent girls in Semnan. In a cross- sectional study, using two-stage random sampling, 256 girl students aged 14-18 years were randomly selected from eight Semnan high schools. Weight and height were measured and BMI was calculated. Weight status was determined based on the CDC 2000 reference for BMI-for-age. Data on socio-demographic factors like age, age at menarche, family size, parental education, parental job and economic status was collected through a questionnaire. Age at menarche and mother's literacy had significant association with weight status (P =0.031, P =0.001 respectively). Logistic regression analyses showed mother's literacy and age at menarche were strong predictors for overweight but not for under weight. Increasing maternal nutritional knowledge is necessary to initiate changes in nutritional conduct. In addition, a longitudinal study of adolescent nutrition and its associated factors is suggested.

Effects of omega-3 fatty acid supplements on serum lipids, apolipoproteins and malondialdehyde in type 2 diabetes patients.

In order to test whether hyperlipidaemia and glycaemic control can be improved among diabetes patients by dietary supplementation with purified omega-3 fatty acids, we carried out a double-blind, placebo-controlled trial on 50 type 2 diabetes patients randomized to 2 g/day purified omega-3 fatty acids or placebo for 10 weeks. Fasting triglycerides decreased significantly with supplementation relative to placebo (P = 0.01). There was a significant decrease in ApoB-100 and malondialdehyde compared to baseline values and compared to the control group. Omega-3 fatty acids had no significant effect on serum lipid levels, ApoA-I, glucose, insulin and HbA1c.

Measurement of the adsorption at solid-liquid interfaces from the pressure dependence of contact angles.

Earlier studies have indicated that in an isothermal three-phase system, the liquid-phase pressure at the three-phase line, xL3, may be viewed as the independent variable of the contact angle, theta, and that adsorption at the solid-liquid interface is the mechanism relating them. When the liquid-vapor interface is axi-symmetric, we show that theta can be predicted as a function of xL3 and that by measuring theta(xL3), the amount adsorbed at the solid-liquid interface can be determined. We consider water in differently sized borosilicate glass cylinders. For progressively larger cylinders, xL3 increases with cylinder radius, but when a particularly sized cylinder is rotated about it longitudinal axis, xL3 is decreased. The observed value of theta in each case is found to be in close agreement with that predicted. A Gibbs model of the interphase is used, and the Gibbs adsorption at the solid-liquid interface is found to be negative. As xL3 increases above its value at wetting, the amount adsorbed at the solid-liquid interface becomes progressively more negative. Negative adsorption is shown to mean that the concentration of the fluid component is greater in the bulk liquid than in the interphase and that the difference in concentration increases as xL3 is increased. The data is used to investigate the hypothesis that the curvature of the three-phase line affects theta through line tension, but we find no relation between line tension and theta. There is an apparent relation between the curvature of the liquid-vapor interface, CLV and theta, but this is shown to be because CLV affects xL3.

Effects of omega-3 fatty acid supplements on serum lipids, apolipoproteins and malondialdehyde in type 2 diabetes patients

In order to test whether hyperlipidaemia and glycaemic control can be improved among diabetes patients by dietary supplementation with purified omega-3 fatty acids, we carried out a doubleblind, placebo-controlled trial on 50 type 2 diabetes patients randomized to 2 g/day purified omega-3 fatty acids or placebo for 10 weeks. Fasting triglycerides decreased significantly with supplementation relative to placebo [P = 0.01]. There was a significant decrease in ApoB-100 and malondialdehyde compared to baseline values and compared to the control group. Omega-3 fatty acids had no significant effect on serum lipid levels, ApoA-I, glucose, insulin and HbA1[c]

Comparison of plasma and leukocyte vitamin C status between asthmatic and healthy subjects.

In a case-control study the vitamin C status of 50 adults with chronic controlled asthma was compared with that of 50 randomly selected healthy controls. Vitamin C intake was assessed by 3-day dietary recall, and plasma and leukocyte vitamin C concentrations were measured colorimetrically. A positive significant correlation was found between plasma vitamin C and dietary vitamin C intake. Plasma and leukocyte vitamin C levels were significantly lower in the asthma group. Plasma vitamin C was deficient (< 0.4 mg/dL) in significantly more patients than controls (38.0% versus 0%) and leukocyte vitamin C (< 20 microg/10(8) leukocytes) was deficient in 92.0% of asthmatics versus 8.0% of controls. A significant association was observed between duration of asthma and plasma vitamin C level.

Comparison of plasma and leukocyte vitamin C status between asthmatic and healthy subjects

In a case-control study the vitamin C status of 50 adults with chronic controlled asthma was compared with that of 50 randomly selected healthy controls. Vitamin C intake was assessed by 3-day dietary recall, and plasma and leukocyte vitamin C concentrations were measured colorimetrically. A positive significant correlation was found between plasma vitamin C and dietary vitamin C intake. Plasma and leukocyte vitamin C levels were significantly lower in the asthma group. Plasma vitamin C was deficient [< 0.4 mg/dL] in significantly more patients than controls [38.0% versus 0%] and leukocyte vitamin C [< 20 micro g/10[8] leukocytes] was deficient in 92.0% of asthmatics versus 8.0% of controls. significant association was observed between duration of asthma and plasma vitamin C level

Serum antibodies to the major proteins found in cow's milk of Iranian patients with Type 1 diabetes mellitus.

The purpose of this study was to assess the humoral immune response to cow's milk proteins in Iranian children with Type 1 diabetes mellitus (T1DM). Eighty children aged 4-17 yr with T1DM from two centres in Iran (the Iranian Association of Diabetes in Tehran and Center for Diabetes Research in Hamedan), 37 apparently healthy siblings of diabetic patients (related controls), 82 apparently healthy age- and sex- matched controls (unrelated controls), and 32 patients aged 11-15 yr with auto-immune thyroiditis were examined for specific whole antibodies (Igs), IgG, and IgM to the major proteins found in cow's milk or to ovo-albumin by enzyme-linked immunosorbent assay (ELISA). A crude extract was made from 2.5% fat pasteurized cow's milk. This extract, together with individual commercial major proteins of cow's milk, was then used as antigen to evaluate the humoral immune response of the subjects to the individual proteins found in cow's milk or to cow's milk as a whole. A questionnaire on medical history, duration of exclusive and non-exclusive breast-feeding and daily intake of dairy products was completed before blood sampling. Diabetic children had significantly higher serum levels of Igs, IgG and IgM to the proteins found in cow's milk than unrelated healthy controls (p<0.001). Healthy siblings of diabetic patients, compared to unrelated controls, had significantly higher levels of serum Igs and IgG to cow's milk proteins (p<0.05 and p<0.01, respectively). Serum levels of Igs and IgG to the cow's milk proteins showed a significantly negative correlation with duration of non-exclusive breast-feeding but positive correlation with daily intake of dairy products. These correlations were stronger when calculated just within the T1DM group. In this group, serum levels of IgM to cow's milk proteins also showed a positive correlation with daily intake of dairy products. Though serum levels of IgG to casein were insignificantly higher in diabetic children than in healthy controls, there was a significant negative correlation between serum levels of IgG to casein and duration of non-exclusive breast-feeding. Again in the T1DM group, this correlation was stronger. There was no significant difference in serum levels of Igs, IgG or IgM to other major proteins of cow's milk or to ovo-albumin between groups. It was concluded that though high levels of Igs or IgG were found to cow's milk proteins, especially casein, it seems unrelated to the early introduction of cow's milk into an infant diet and the onset of T1DM in Iranian subjects.

Determination of line tension for systems near wetting.

Contact angle measurements for three n-alkanes, heptane, octane, and nonane, on two different self-assembled surfaces (SAM) are reported as a function of drop size. These liquids all formed low contact angles (below 20 degrees ); the measurements were performed using an accurate method for systems with low contact angle, ADSA-D. The observed drop size dependence of the contact angles was interpreted using the modified Young equation. It was concluded that the observed drop size dependence of contact angles was due to line tension. The choice of systems also provided the opportunity to examine the behavior of the line tension for systems near wetting (i.e., low contact angles). It was determined that the line tension is positive and ranges from below 10(-7) to just below 10(-6) J/m for the systems studied; the observations suggested that the line tension decreases as the contact angle decreases and likely vanishes at complete wetting.

Iron status and socioeconomic determinants of the quantity and quality of dietary iron in a group of rural Iranian women.

Iron intake and status were investigated in 471 mothers (age range: 16-53 years) from rural areas in Khorramabad, Islamic Republic of Iran. Although average total iron intake was acceptable, only 6.4% of women derived at least 4% of their total intake from animal iron. Average energy and protein intakes were inadequate. Low iron status was seen in 8.2%-28.7%, depending on the parameter used, with 28.3% experiencing iron-deficiency anaemia. Significantly higher animal iron intakes were found in literate or employed women, or those of family size fewer than six people. Increasing employment opportunities, income levels and literacy rates for women will result in better iron intake and status and should receive particular attention in national planning.

Iron status and socioeconomic determinants of the quantity and quality of dietary iron in a group of rural Iranian women

Iron intake and status were investigated in 471 mothers [age range: 16-53 years] from rural areas in Khorramabad, Islamic Republic of Iran. Although average total iron intake was acceptable, only 6.4% of women derived at least 4% of their total intake from animal iron. Average energy and protein intakes were inadequate. Low iron status was seen in 8.2%-28.7%, depending on the parameter used, with 28.3% experiencing iron-deficiency anaemia. Significantly higher animal iron intakes were found in literate or employed women, or those of family size fewer than six people. Increasing employment opportunities, income levels and literacy rates for women will result in better iron intake and status and should receive particular attention in national planning

Reproductive function in men following exposure to chemical warfare with sulphur mustard.

To investigate the acute and chronic effects in young men of exposure to chemical warfare containing mustards, the time course of changes in serum concentrations of total and free testosterone, dehydroepiandrosterone (DS), follicle-stimulating hormone (FSH), luteinizing hormone (LH) and prolactin was evaluated in 16 men in the first three months and testicular function in 42 men one to three years after injury. Serum total and free testosterone and DS were markedly decreased in the first five weeks after exposure. The lowest values were: total testosterone 237 +/- 165, free testosterone 22.5 +/- 9.7, DS 39 +/- 25; as compared to controls: total testosterone 773 +/- 245 ng/dl, free testosterone 35.5 +/- 11.2 pg/ml and DS 207 +/- 37 micrograms/dl. FSH, LH, prolactin and 17 alpha-OH progesterone were normal in the first week. The response to GnRH was subnormal in four of five subjects. LH increased by the third and FSH and prolactin by the fifth week. All hormone levels had returned to normal by twelfth week after exposure. In 28 of 42 men seen one to three years following injury, sperm count was below 30 million cells/ml, and FSH was increased as compared to men with sperm above 60 million cells/ml. Testicular biopsy showed complete or relative arrest of spermatogenesis. This study demonstrates that the exposure to sulphur mustard results in very low androgen levels and hypo-responsiveness to GnRH in the first five weeks and normalization by the twelfth week after injury. However, side effects of mustard on sperm cells persist and may cause defective spermatogenesis years after exposure.

[Formation of nitrosamines in cheese products]. / Formation de nitrosamines dans les produits fromagers.

Several strains of micromycetes used as fermentation agents in the cheese industry or having led to accidents during cheese making are able to favor the formation of nitrosamines in 60% of the cases. The concentrations observed are similar to those found by other authors with other microorganisms. The results obtained in a semi-synthetic medium are checked during the ripening of experimental camembert type cheese made from milk containing nitrates and cultured with a strain of Penicillium camemberti, which favors very much the synthesis of nitrosamines. The amount of nitrosodimethylamine formed in this cheese increases from 5 to 20 ppb during ripening. A tentative explanation of the mechanism of formation is outlined.