Dioxins and furans maternal transfer: A study of breast milk and cord serum levels among Lebanese mothers and associations with newborn anthropometric measurements

Dioxins and furans (PCDD/Fs) are anthropogenic pollutants that persist in the environment for long years, bioaccumulating in food & contaminating humans. In pregnancy, they can transfer through the placenta and reach the fetus, which negatively affects fetal growth. They can also reach newborns through breastfeeding. In this study, we focused on this critical subpopulation and identified the presence of PCDD/Fs among pregnant women in breast milk (n = 41) and cord serum (n = 49); we assessed the correlation between different matrices, evaluated the predictors and associations with newborn anthropometric measurements. Over 70.7 % of PCDD/Fs were detected in breast milk and 46.9-55.1 % in cord serum. Cord/maternal serum and breast milk to maternal serum ratios were > 1 with a significant positive Spearman correlation (0.669-0.729). Breast milk & maternal serum PCDD/Fs were associated inversely with age and positively with red meat intake. Cord serum PCDD/Fs were inversely associated with pre-pregnancy weight loss and passive smoking. Parity and gestational weight gain showed positive associations with Z-scores at birth. Z-score differences showed negative and positive associations with passive smoking and pre-pregnancy BMI respectively.

Evaluation of Peer Review Practice in Radiation Oncology Treatment Planning: Single Institution Experience

PURPOSE/OBJECTIVE(S)

Pretreatment Peer review meeting at our radiation oncology department is a weekly meeting, where the initial radiation treatment (RT) planning process for every patient is discussed including: Computed Tomography (CT) simulation and treatment planning. In this study, we are aiming to evaluate our peer review process and to report the compliance to the suggested modifications.

MATERIALS/METHODS

All RT plans for all patients indicated for radiotherapy accepted by the primary radiation oncology team then presented in our weekly peer review meeting for final approval. A minimum of two radiation oncologists reviewed each plan and their suggestions documented then suggested modifications are classified as changes in: field arrangement, clinical target volume (CTV), dose and fractionation. Compliance to suggested modification also recorded as: applied and not applied with or without documented justification.

RESULTS

Atotal of 1779 radiation treatment plans were discussed in our regular weekly peer review meetings for a period of 3 years. 67.5% of them were treated with radical intent while 32.5% treated with palliative intent. The most common technique used was three-dimensional conformal (3DCRT) followed by intensity modulated RT (IMRT) (70.6% and 29.4%, respectively). The most frequently reviewed sites were: breast (38%), Gastrointestinal (11.9%) and head and neck (9.3%).1592 plans (89.48%) were labeled as: approved, 162 (9.1%) labeled as: modified and only 25 (1.4%) plans labeled as: hold. The frequency of modifications was significantly greater in breast (39.5%) than Gastrointestinal (17.9%) followed by gynecological cancers (14.2%) (P value <0.001). Modifications were more predominant with radical plans (64.2%) than palliative ones (35.8%) (P value <0.001) and statistically greater using 3DCRT (64.2%) than IMRT (35.8%) (P value <0.001). CTV recorded as the most frequent variable suggested for modifications (34.6%), followed by dose and fractionation (24.7%) (P value = 0.035). 72.2% of recommended modifications were applied by the consultant of primary team and 22.2% of non-applied modifications were justified and documented. There was 100% compliance rate to all plans labeled as hold.

CONCLUSION

The practiceof peer review in radiation oncology specialty is very challenging. Its role in quality assurance of the radiotherapy process is highly accepted by radiation oncologists at our radiation oncology department. It is reflected in their high compliance rate to the suggested modifications. We recommend its implementation routinely at any radiation oncology department to enhance the quality of RT plans.

Physical Activity Levels and Predictors during COVID-19 Lockdown among Lebanese Adults: The Impacts of Sociodemographic Factors, Type of Physical Activity and Work Location

BACKGROUND

Although effective against COVID-19, national lockdowns have several deleterious behavioral and health effects, including physical inactivity. The objective of this study is to assess physical activity (PA) levels during lockdown and the predictors of PA among Lebanese adults, while comparing classical statistics to machine learning models.

METHODS

Data were collected using an online questionnaire, with PA being evaluated through the "International Physical Activity Questionnaire" (IPAQ)-long form. Machine learning models were applied to predict total PA ≥ 600 MET·min/week.

RESULTS

Among 795 participants, while 67.5% auto-declared a decrease in PA level during lockdown, 36.2% did not meet the minimum recommendations for PA. Multivariate analysis showed that participants who went to their workplace during lockdown had significantly higher total and job-related PA, higher walking and moderate PA, and lower sitting time. PA level and intensity increased with age, while sitting time decreased. Participants who practiced a combination of both outdoor and at-home workouts had higher total, housework and leisure-related PA, and higher moderate and vigorous-intensity PA. Machine learning models confirmed these findings as well as the importance of outdoor activity for total PA levels, with Random Forest being the highest-performing model.

CONCLUSIONS

Bringing to light the levels of physical inactivity and sedentary behavior, this study highlighted the importance of outdoor activity in contributing to PA.

Maternal Serum, Cord and Human Milk Levels of Per- and Polyfluoroalkyl Substances (PFAS), Association with Predictors and Effect on Newborn Anthropometry

BACKGROUND

The understanding of per- and polyfluoroalkyl substances (PFAS) health effects is rapidly advancing among critical populations. Therefore, the objective of this study was to assess PFAS serum levels among Lebanese pregnant women, cord serum and human milk levels, their determinants, and effects on newborn anthropometry.

METHODS

We measured concentrations of six PFAS (PFHpA, PFOA, PFHxS, PFOS, PFNA and PFDA) using liquid chromatography MS/MS for 419 participants, of which 269 had sociodemographic, anthropometric, environmental and dietary information.

RESULTS

The percentage of detection for PFHpA, PFOA, PFHxS and PFOS was 36.3-37.7%. PFOA and PFOS levels (95th percentile) were higher than HBM-I and HBM-II values. While PFAS were not detected in cord serum, five compounds were detected in human milk. Multivariate regression showed that fish/shellfish consumption, vicinity to illegal incineration and higher educational level were associated with an almost twice higher risk of elevated PFHpA, PFOA, PFHxS and PFOS serum levels. Higher PFAS levels in human milk were observed with higher eggs and dairy products consumption, in addition to tap water (preliminary findings). Higher PFHpA was significantly associated with lower newborn weight-for-length Z-score at birth.

CONCLUSIONS

Findings establish the need for further studies, and urgent action to reduce exposure among subgroups with higher PFAS levels.

Serum levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in a sample of Lebanese pregnant women: The role of dietary, anthropometric, and environmental factors

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are unintentionally produced, toxic environmental chemicals that persist for long years and bioaccumulate along the food chain, contaminating humans through diet. A particularly critical population subgroup is pregnant women given the adverse health effects on fetuses and newborns. Several anthropogenic sources of exposure to PCDD/Fs exist in Lebanon. Therefore, the aim of the present cross-sectional study is to measure the levels of PCDD/Fs in a sample of pregnant women in Lebanon and to explore potential associated factors. In this study, we measured serum concentrations of seven dioxins and ten furans, among 423 pregnant women recruited at delivery, using gas chromatography MS/MS. Among 269 participants, maternal sociodemographic information was collected including vicinity to landfills, incineration, pesticide use, industrial activity, and smoking. Anthropometric data were registered regarding pre-pregnancy body mass index (BMI), pre-pregnancy weight loss from restrictive diet, and gestational weight gain. Intake of major food groups generally related to PCDD/Fs was reported (fish, red meat, poultry, and dairy). Bivariate and multivariate analyses were performed to identify associations. PCDD/Fs were detected in 0 to 56.1% of the sample. Geometric mean concentrations were 75.5 (2.35) pg/g lipid and 2.25 (1.39) TEQ₂₀₀₅ pg/g lipid for total dioxins, and 2.66 (1.76) pg/g lipid and 0.34 (1.78) TEQ₂₀₀₅ pg/g lipid for total furans. Levels were relatively lower than levels previously observed in France, Germany, Mexico, Ghana, and Japan. Red meat consumption was the most consistently associated factor with a 2.38-2.57 fold increase in PCDD/F levels. Pre-pregnancy weight loss showed inverse associations with PCDD/F congeners. Vicinity to illegal incineration was also associated with a 2.32-2.43 fold increase in PCDD/F levels. In conclusion, results showed the importance of dietary, anthropometric, and environmental factors in the present sample's exposure to PCDD/Fs, in a region that contains anthropogenic sources of contamination.

Association between dietary quality indices and serum polychlorinated biphenyls and organochlorine pesticides levels among Lebanese adults

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) remain a global concern in both developed and developing countries. Given that diet constitutes the major route of exposure to these pollutants, the objective of the current study is to investigate PCBs and OCPs serum levels in relation to dietary quality indices in a sample of Lebanese adults. Sociodemographic, nutritional, and anthropometric data were obtained from 302 participants in face-to-face interviews. Nutritional intakes from a previously validated quantitative 164-item food frequency questionnaire were used to calculate six a priori dietary indices: Healthy Eating Index (HEI-2015), alternate Healthy Eating Index (aHEI), Diet Quality Index-International (DQI-I), Mediterranean Diet Quality Index (Med-DQI), Med-DQIf, Mediterranean Diet Scale (MDS), and Mediterranean Diet Score (MedDietScore). Serum levels of six indicator PCBs (PCBs 28, 52, 101, 138, 153, 180) and four OCPs (HCB, β-HCH, DDT, and DDE) were investigated in relation to diet quality indices. Individuals with a higher adherence to the HEI-2015 and to the Mediterranean diet assessed by the Med-DQI/Med-DQIf displayed increased levels of OCPs (HCB, βHCH, DDT, and DDE). An inverted U-shaped association was observed between DQI-I and PCBs serum levels (PCBs 138, 153, 180, and ƩPCBs). This is the first study in the Middle East and North Africa region to investigate the association between POPs serum levels and a substantial number of a priori dietary indices. The impact of different food combinations and nutrient interactions on pollutants body burden and toxicity remains to be established in future studies.

Maternal and cord serum levels of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) among Lebanese pregnant women and predictors of exposure

In this study, the six indicator non-dioxin-like polychlorinated biphenyls NDL-PCBs (PCB28, PCB52, PCB101, PCB138, PCB153, PCB180), as well as four organochlorine pesticides (OCPs), hexachlorobenzene (HCB), β-hexachlorocyclohexane (β-HCH), dichlorodiphenyltrichloroethane (DDT), and dichlorodiphenyldichlorethylene (DDE) were measured in 98 maternal and 49 cord sera samples of a group of Lebanese women who gave birth in three hospitals in Greater Beirut, between March and July 2018. Results showed that the levels of these persistent organic pollutants (POPs) in maternal serum were below critical limits as well as those in other countries (Tunisia, France, Portugal, Spain, Poland, Greenland, Canada, Brazil, and China). The ratios of cord serum concentrations to maternal serum concentrations of analyzed POPs were higher than 1. PCB maternal serum concentrations were found to be linked to illegal incineration (OR = 5.78; p = 0.004) as well as eggs (OR = 4.68; p = 0.027) and fruits and vegetables consumption (OR = 3.92; p = 0.016). OCP concentrations were linked to red meat and cold cuts intake (OR = 3.67-4.59; p = 0.001-0.004). While PCB levels were not correlated to newborns anthropometric measurements, OCP levels in cord serum were found to be positively linked to the birth length of newborns (p = 0.014-0.027).

Development and validation of a quantitative food frequency questionnaire to assess dietary intake among Lebanese adults

BACKGROUND

The food frequency questionnaire (FFQ) is the most frequently used method to assess dietary intake in epidemiological studies evaluating diet-disease association. The objective of this study was to validate a FFQ for use among Lebanese adults by evaluating various facets of validity and reproducibility.

METHODS

The quantitative 164-items FFQ was validated against the average of six 24-h dietary recalls (DRs) in a sample of 238 Lebanese adults. Reproducibility of the FFQ was assessed by administering it twice within 1 month' time interval.

RESULTS

Positive statistically significant Pearson correlations were observed in most macro and micronutrients between the FFQ and the six 24-h DRs, ranging from 0.16 to 0.65, with two thirds of the correlation coefficients exceeding 0.3. Energy, gender, and age-adjusted statistically significant Pearson correlation coefficients ranged from 0.14 to 0.64, with two thirds of the coefficients exceeding 0.2. Intakes from the FFQ were mostly higher than those of the 24-h DRs. Mean percent difference between nutrient intakes from both dietary methods decreased remarkably after using energy-adjusted mean intakes. Values were acceptable to good for all macronutrients and several micronutrients. Cross-classification analysis revealed that around 64.3 to 83.9% of participants were classified into the same and adjacent quartile whereas grossly misclassified proportions ranged from 3.7 to 12.2%. Weighted kappa values ranged from 0.02 to 0.36 with most of them exceeding 0.2. In indirect validity analysis, key nutrient mean intakes estimated from the six 24-h DRs were significantly positively associated with tertiles of food groups derived from the FFQ. Bland Altman plots showed that the majority of data points fell within the limits of agreement (LOA) for all nutrients. As for reproducibility analysis, ICC values were all statistically significant ranging from 0.645 to 0.959 and Bland Altman plots confirmed these results.

CONCLUSIONS

Based on various aspects of validity and reproducibility, and an extensive range of statistical tests, the present FFQ developed for a Lebanese community is an acceptable tool for dietary assessment and is useful for evaluating diet-disease associations in future studies.

Combined effect of physical activity and sedentary behavior on body composition in university students

BACKGROUND & AIMS

This study aimed to evaluate the domain-specific physical activity (PA) levels and sitting time of a sample of university students and examine the association of PA with percent body fat.

METHODS

Two hundred and twenty-one students were included in the analysis. We administered the long form of the International Physical Activity Questionnaire (IPAQ) twice within one-month interval. Total PA as well as occupational, transportation-, housework-, and leisure-related PA were assessed, in addition to sitting time. Dietary intake was derived from six non-consecutive 24-hour dietary recalls. Percent body fat (dependent variable) was analyzed using a bioelectrical impedance analyzer (BIA). Multivariate logistic regression, adjusted for potential confounders, examined the associations of domain-specific PA and sitting time with percent body fat.

RESULTS

Men had higher levels of total and leisure PA than women. All participants had prolonged sitting time, with 48% having a sitting time of more than 10.15 hours/day. In multivariate analysis, moderate leisure PA, compared to vigorous PA was associated with a lower percent body fat. This association remained statistically significant even after adjustment for energy intake and sitting time. Housework-related PA was associated with a higher percent body fat.

CONCLUSION

Moderate leisure PA was highly associated with percent body fat even after adjustment for confounding variables. Adequate interventions targeting this kind of leisure should be promoted among universities students.

Validity and reliability of an adapted arabic version of the long international physical activity questionnaire

Background

The International Physical Actvity Questionnaire (IPAQ) is a validated tool for physical activity assessment used in many countries however no Arabic version of the long-form of this questionnaire exists to this date. Hence, the aim of this study was to cross-culturally adapt and validate an Arabic version of the long International Physical Activity Questionnaire (AIPAQ) equivalent to the French version (F-IPAQ) in a Lebanese population.

Methods

The guidelines for cross-cultural adaptation provided by the World Health Organization and the International Physical Activity Questionnaire committee were followed. One hundred fifty-nine students and staff members from Saint Joseph University of Beirut were randomly recruited to participate in the study. Items of the A-IPAQ were compared to those from the F-IPAQ for concurrent validity using Spearman’s correlation coefficient. Content validity of the questionnaire was assessed using factor analysis for the A-IPAQ’s items. The physical activity indicators derived from the A-IPAQ were compared with the body mass index (BMI) of the participants for construct validity. The instrument was also evaluated for internal consistency reliability using Cronbach’s alpha and Intraclass Correlation Coefficient (ICC). Finally, thirty-one participants were asked to complete the A-IPAQ on two occasions three weeks apart to examine its test–retest reliability. Bland-Altman analyses were performed to evaluate the extent of agreement between the two versions of the questionnaire and its repeated administrations.

Results

A high correlation was observed between answers of the F-IPAQ and those of the A-IPAQ, with Spearman’s correlation coefficients ranging from 0.91 to 1.00 (p < 0.05). Bland-Altman analysis showed a high level of agreement between the two versions with all values scattered around the mean for total physical activity (mean difference = 5.3 min/week, 95% limits of agreement = −145.2 to 155.8). Negative correlations were observed between MET values and BMI, independent of age, gender or university campus. The A-IPAQ showed a high internal consistency reliability with Cronbach’s alpha ranging from 0.769–1.00 (p < 0.001) and intraclass correlation coefficient (ICC) ranging from 0.625–0.999 (p < 0.001), except for a moderate agreement with the moderate garden/yard activity (alpha = 0.682; ICC = 0.518; p < 0.001). The A-IPAQ had moderate-to-good test-retest reliability for most of its items (ICC ranging from 0.66–0.96; p < 0.001) and the Bland-Altman analysis showed a satisfactory agreement between the two administrations of the A-IPAQ for total physical activity (mean difference = 99.8 min/week, 95% limits of agreement = −1105.3; 1304.9) and total vigorous and moderate physical activity (mean difference = −29.7 min/week, 95% limits of agreement = −777.6; 718.2).

Conclusion

The modified Arabic version of the IPAQ showed acceptable validity and reliability for the assessment of physical activity among Lebanese adults. More studies are necessary in the future to assess its validity compared to a gold-standard criterion measure.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-017-4599-7) contains supplementary material, which is available to authorized users.

Effect of Curcumin on LDL Oxidation in Vitro, and Lipid Peroxidation and Antioxidant Enzymes in Cholesterol Fed Rabbits

In this study we examined the antioxidant effect of curcumin on lipid oxidation in vitro and in vivo. In vitro, curcumin at 5 microgM concentration completely prevented low-density lipoprotein (LDL) oxidation by CuS04, indicating that curcumin is an effective antioxidant in vitro. In vivo, feeding a pure cholesterol (PC)-rich diet to rabbits significantly increased the plasma and liver lipids as well as thiobarbituric acid reactive substances (TBARS) levels. Addition of curcumin to the PC diet did not show any effect on either plasma lipid and TBARS or liver lipids. Liver TBARS tended to decrease but that decrease was not significant. Erythrocyte glutathione peroxidase (GSH-Px) activity was significantly decreased while catalase activity was significantly increased in rabbits fed a PC diet. The addition of curcumin to a PC diet did not show any significant effect on erythrocyte enzyme activities compared to the rabbits fed a PC diet. The liver GSH-Px and catalase activities were significantly decreased in rabbits fed a PC diet, but the addition of curcumin to the PC diet enhanced the liver GSH-Px activity, which became nonsignificantly different from the control group. These results were discussed considering that curcumin may not be well absorbed and it did not reach a level high enough in vivo to overcome the severe hypercholesterolemia and oxidative stress produced by the PC-rich diet.

Biogenic cements from rice hull ash doped with aluminum and iron

This work describes the use of rice hull as starting material for the synthesis of cements doped with iron and aluminum. Rice hull contains about 10-20% of silica along with organic material. In many countries rice hull represents an environmental problem since this material is merely burned at rice fields, rendering suspended silica particles in the air. Dicalcium silicate (beta-Ca(2)SiO(4)) is the second most important component of Portland cement and presents many environmental advantages over commercial cement. It can be prepared at lower temperatures saving energy and raw-materials. In this work we describe the synthesis beta-Ca(2)SiO(4) using silica derived from rice hull ash. Silica was obtained from heating rice hull at 600 degrees C. Starting materials (silica, calcium oxide, barium chloride, iron or aluminum oxide) were weighed in stoichiometric proportions and aqueous dispersions having water:solid ratio of approximately 20:1 were prepared and treated in an ultrasonic bath for 60 min. After this, an intermediate silicate and the excess of calcium hydroxide were obtained. Finally solids were dried, grounded and heated up to 800 degrees C. It was observed that beta-Ca(2)SiO(4) was obtained when dopant concentration was limited to 1%.

Changes in rat olfactory detection performance induced by orexin and leptin mimicking fasting and satiation

Numerous peripheral and hypothalamic peptides control food intake. Among these signals are orexin, an orexigenic molecule released into the olfactory bulb by centrifugal hypothalamic fibres and leptin, an anorexigenic molecule that is released peripherally and can pass through the blood-brain barrier. In the present study, we injected either orexin or leptin, intracerebroventricularly, and their effect on olfactory performance was evaluated in two groups of rats, using a behavioral paradigm based on conditioned olfactory aversion. Rats were made aversive to water odorized with isoamyl acetate (ISO) at 10(-5) (1microl in 100ml of water). One group was injected with orexin versus saline and the other with leptin versus saline. They were then presented with different concentrations (lower than 10(-5)) of ISO-odorized water to compare their ability to avoid the ISO-drink. Orexin decreased ISO-drink consumption, showing increased avoidance of the ISO concentrations tested which ranged from 10(-9) to 10(-7). Conversely, the administration of leptin resulted in a dose dependant increase in the odorized-drink consumption for ISO 10(-10). Orexin therefore increases and leptin decreases olfactory sensitivity. Orexin and leptin modulate the olfactory performance in a similar way as do physiological induced fasting and satiation and appear to be important factors in the interdependency of olfaction and food intake.

[Laparoscopic appendectomy as training procedure for all stages of appendicitis]

Appendectomy is one of the most common procedures in general surgery. Appendectomy is routinely performed in our department laparoscopically and as a training procedure for all stages of appendicitis. Between 1.1.2003 till 31.7.2005 642 patients underwent appendectomy. 613 of them were performed laparoscopically with a conversion rate of 0,6% in uncomplicated findings and 8,1% in complicated findings (perforated, abscess and gangrenous appendicitis). The postoperative recovery after laparoscopic appendectomy was without any significant complication in 98.2% of the patients with acute appendicitis and 89% of the patients with complicated findings. The overall morbidity rate in both situations (uncomplicated and complicated findings) did not differ from that described in literature. This supports impressively our thesis that laparoscopic appendectomy is feasible in all situations, with a high value for training young surgeons.

Fasting increases and satiation decreases olfactory detection for a neutral odor in rats

Olfaction plays a fundamental role in feeding behavior, but changes in olfactory acuity according to feeding states have never been precisely demonstrated in animals. The present study assesses the olfactory detection performance of fasted or satiated rats placed under a strictly controlled food-intake regimen. We did this using a conditioned odor aversion (COA) protocol which induced in rats an almost total aversion to an ISO-odorized drink at 10(-5) (1 microl in 100 ml of water). The rats (either fasted or satiated) were then presented with different concentrations of ISO-odorized water to compare their ability to detect and so avoid the ISO drink. In both states, the rats consumed significantly larger volumes of ISO at 10(-10), 10(-9) and 10(-8) than at 10(-5), suggesting lower detection at these three concentrations, although the fasted rats consumed significantly less ISO drink than did the satiated ones, showing better ISO detection at these concentrations. These experiments provide original data demonstrating the expected fact that olfactory sensitivity increases in fasted animals. Since these results were obtained using a neutral odor, we suggest that olfactory acuity increases during fasting, enabling animals to more easily detect both food and environmental odors such as those of predators. This would have an obvious eco-ethological role by increasing the relevance of olfactory inputs when seeking food.

Inhibition of prostacyclin release by cigarette smoke extract in endothelial cells is not related to enhanced superoxide generation and NADPH-oxidase activation

Exposure of human umbilical endothelial cells (ECs) to cigarette smoke extract (CSE) activated the NADPH-oxidase enzyme and increased the production of superoxide (O-2) as well as reactive oxygen species (ROS). CSE also inhibited the prostacyclin (PGI2) formation by ECs. Preincubation of ECs with diphenylene iodonium (DPI), the inhibitor of NADPH oxidase, blocked the increase of O-2 production, but neither lowered the ROS level nor prevented the inhibition of PGI2 formation in CSE-treated cells. Preincubation of ECs with a medium supplemented with 1 mM vitamin C did not decrease, but rather increased the O-2 production in CSE-treated cells. However, adding 1 mM glutathione (GSH) to vitamin C decreased the O-2 production, indicating that vitamin C was overwhelmed by the prooxidant in CS, and GSH enhanced the recycling process and spared vitamin C. The ROS level remained high in CSE-treated cells even after preincubation with vitamin C or vitamin C + GSH compared to the control cells. These results are discussed in light of the possible decrease of antioxidant enzyme activities in CSE-treated cells and the increase of cellular hydrogen peroxide (H2O2) generated from the CSE, which cause an imbalance between oxidizing species and the antioxidants producing oxidative stress in CSE-treated cells. These results demonstrate that CSE has a direct inhibitory effect on PGI2 formation and enhances the level of ROS in CSE-treated ECs, regardless of the activation of NADPH-oxidase.

Oxidized low density lipoprotein inhibits prostacyclin generation by rat aorta in vitro: a key role of lysolecithin

The objective of this study was to examine the effect of oxLDL on prostacyclin (PGI2) generation by rat aortic segments and to see whether the lipid fraction of oxLDL or its components are responsible for that effect. We also tested if antioxidants have any protective role. LDL oxidized by copper was characterized by higher TBARS, conjugated diene, lysophosphatidylcholine (lyso PC), oxysterols and less polyunsaturated fatty acids (PUFA) than nLDL. Preincubation of aortas with oxLDL caused a significant inhibition of PGI2 generation compared to aortas preincubated with nLDL or buffer only. The percent inhibition was dependent on the concentration of oxLDL. Most of the inhibitory effect of oxLDL resided in its lipid moiety while the lipid fraction of nLDL, as well as native LDL had no effect. Preincubation of aortas with 10 microg/ml of 7-ketocholesterol the major oxysterol in oxLDL reduced the amount of PGI2 generated by aorta at all times tested; however that decrease did not reach a significant level. Aortas preincubated with 10 microg/ml of lyso PC showed a 21-36% inhibition of PGI2 generation which was comparable to the inhibition produced by preincubating the aortas with 50 microg protein/ml of oxLDL (containing about 7.5 microg lyso PC). This indicated that most of the inhibitory effect of oxLDL was due to its lyso PC. The small molecular weight fraction (< 10 kDa) with a high level of TBARS (TBARS solution) also significantly decreased the PGI2 generation by aorta. Addition of superoxide dismutase (SOD) + catalase or vitamin E simultaneously with oxLDL or TBARS solution in the preincubation medium did not reverse their inhibitory effects. This indicated that oxygen free radicals are not a contributing factor to the inhibitory effect of oxLDL but lyso PC and the lipid peroxides and probably other components already present within oxLDL are the important inhibitors.

Cholesterol metabolism in human umbilical arterial endothelial cells cultured in low magnesium media

Epidemiological and experimental studies have shown that magnesium is closely related to regulation of lipid metabolism, membrane structure and permeability, ion migration through cellular membranes, endocrine hormone and platelet function. The cause of atherosclerosis induced by magnesium deficiency has been suggested to be due to abnormal lipid metabolism, lipid peroxidation, a decrease of prostacycline produced by endothelial cells, and an increase of platelet aggregation. We found that the plasma from cardiac catheterized patients suffering from chest pains contained higher levels of oxysterols than age and sex matched patients free of chest pain. Studies with cultured arterial cells in media deficient in magnesium or containing oxysterols indicated that both magnesium and oxysterols have an important role in lipid metabolism in patients with coronary heart disease.

Parkinson's disease, cognition and aging. Clinical, neuropsychological, electrophysiological and cranial computerized tomographic assessment

Forty-three patients with Parkinson's disease (PD) and thirty-seven normal volunteers were subjected to clinical, neuropsychological, neurophysiological (P300 component of the event-related potentials ERP) and radiological (cranial computerized tomographic scanning CCT) evaluation. Intentional memory was more impaired in PD than in normal controls, more so in the demented group of patients, and was related to enlargement of third ventricular size in CCT. While intentional memory was age related in PD patients, perception was age-related in normal controls. Neither global nor specific cognitive functions were related to duration, severity of parkinsonian motor disability, or depression. However, depression in PD was significantly related to parkinsonian motor disability. P300 latency was more prolonged in PD patients than normal controls. P300 parameters of PD patients were not influenced by age, cognitive functions, duration or severity of motor disability, or depression. The reaction time was the only P300 parameter that was age-related in normal controls. Subcortical atrophy as indicated by CCT was more marked in PD and correlated with age in both patients and controls. Subcortical atrophy was significantly related to cognitive functions in PD but not in normal controls. It was concluded that cognitive impairment in PD could be attributed to complex cognitive changes rather than age. It is a disease process, though not directly related to parkinsonian motor disability or depression. PD differed from normal aging as regards the effect of age on the specific cognitive functions, where in PD patients, age was related to intentional memory, yet in normal controls, it was related to perception. Intentional memory deterioration was found to be specific of PD, being related to subcortical atrophy as well as being more pronounced in the demented group of patients.

Brain aging in normal Egyptians: neuropsychological, electrophysiological and cranial tomographic assessment

Eighty-eight normal Egyptian volunteers above the age of 40 years were studied for brain aging and subjected to neuropsychological (the Paced Auditory Serial Addition Test; the Trailmaking test A, B; the Digit Symbol Substitution Test; sensory and secondary memory tests), electrophysiological (computerized EEG, P300 and reaction time measures), and Computerized Cranial Tomography (CCT) assessment. A significant correlation was found between age and both perception (Digit Symbol Substitution Test (DDST) and psychomotor performance (Trailmaking B test (TMb)), reaction time (RT) and the size of the third ventricle. Whereas females were worse in attention (Paced Auditory Serial Addition Test (PASAT)), males had worse performance in secondary memory test. Elderly subjects with vascular risk factors did worse in psychomotor performance (TMa) than subjects with no risk factors. Non-educated subjects showed worse perception (DSST) than educated subjects. A significant decrease in upper and lower limit percent power of the alpha band was found in subjects above 60 years, males, and non-educated subjects. A significant increase in theta activity was found only in non-educated subjects. It is concluded that decline in specific cognitive functions occurs with advancing age. Vascular risk factors and lack of education early in life enhance these changes. Moreover, the EEG slowing in the elderly was linked to lack of education early in life.

Changes in linoleic acid metabolism and membrane fatty acids of LLC-PK cells in culture induced by 5 alpha-cholestane-3 beta,5,6 beta-triol

The aim of this study was to investigate the effect of the oxysterol 5 alpha-cholestane-3 beta,5,6 beta-triol (triol) on the metabolism of linoleic acid (18:2n-6) to arachidonic acid (20:4n-6) and on the cell membrane fatty acid composition. Porcine kidney cells were incubated in medium with or without 10 microgram(s)/mL of triol for 24 h, then incubated for 1, 6, or 12 h in a medium which contained 50 muM of either [14C] linoleic acid or unlabeled linoleic acid. The cellular uptake of [14C] linoleic acid was significantly higher in the triol-treated cells than in control cells. After 1- and 6-h incubations despite the increase of [14C] linoleic acid pool size in the triol-treated cells, neither total n-6 polyunsaturated fatty acids (PUFA) metabolites nor arachidonic acid were increased in the triol-treated cells as compared to the control cells, but trienoic acids accumulated to a greater extent in the triol-treated cells. Therefore, the ratios of n-6 PUFA metabolites vs. pool size of linoleic acid and of tetraenoic acids vs. dienoic acids were significantly decreased in triol-treated cells as compared to the control cells. The cellular fatty acid composition also showed that linoleic acid percentage was significantly increased while arachidonic acid percentage was significantly decreased in the triol-treated cells, and that the accumulation of trienoic acids (18:3n-6 + 20:3n-6) observed from the [14C] linoleic acid experiment was due solely to increased 20:3n-6 content. This latter finding indicates that a decrease of elongase activity by triol is unlikely. Our results also showed that the triol-treated cells had a lower level of free cholesterol but higher levels of phospholipid and triol in their membranes, suggesting that triol displaced free cholesterol from the cell membrane.

Radionuclide study of the blood ocular barrier

The purpose of this study was to investigate the permeability and clinical significance of the blood-ocular barrier. A new technique using systemic, subtenon, and retrobulbar injections was applied to the study of intraocular penetration of labelled steroid compound. The study was carried out in normal rabbits and in animals with artificially induced intraventional inflammation. It is concluded that there is no blood-vitreous barrier, a vague concept in any case, in the anterior region of the vitreous where free diffusion was observed between the anterior and posterior segments of the eye. High concentration of the labelled steroids was found in the cornea with the peak of activity usually at 30 minutes. However, traces of activity were detectable for up to 4 hours. This indicates the need for a depot long term respiratory form of corticosteroid that would deliver a high concentration of the medication. Local subtenon's and retrobulbar injections resulted in a relatively higher ocular I-125 Cortisol concentration than obtained by systemic route. It is concluded therefore that a high concentration of steroids applied locally will give better and less deletrious effects than systemic administration. Subtenon injection resulted in higher activity in various ocular tissues especially aqueous and vitreous. However, the I-125 Cortisol was rapidly cleared regardless of the route of administration.

Biochemical changes induced in human plasma by its lipoprotein lipase

1. Incubation of human citrated plasma with a concentrate of lipoprotein lipase (separated from the same plasma pool), for 6 hr at 37 degree C and pH 7.0, caused a marked decrease in the concentrations of calcium, triglycerides, total phosphorus, lipid phosphorus and total fatty acids. 2. There was a concomitant increase in the concentrations of non-esterified fatty acids and inorganic phosphorus which were presumably formed by enzymatic hydrolysis of triglycerides and lipid phosphorus. 3. These changes in human plasma, induced by its lipoprotein lipase, were quantitatively comparable to the same changes which have been previously reported in liquid plasma between the 1st and 2nd months of storage at room temperature.

Multielement analysis of fingernail, scalp hair and water samples from Egypt (a preliminary study)

Scalp hair, fingernail and water samples collected from different parts of Egypt are analysed by atomic absorption spectrophotometry and neutron activation analysis. The results for hair show minimum variation of Zn among different regions; a relatively well-controlled dispersion of values (maximum to minimum less than 2) for Co, Fe, Mn and Se; an overall inter-regional variation of factors of 7, 10, 6, 4 and 6 for the elements Ag, Cd, Cs, Sc and W, respectively; a steady decline in the concentration of Sc from south (Aswan) to north (Alexandria). The findings for nail show a steady decline in the concentration of Fe and Sc from south (Aswan) to north (Alexandria); elevated levels of Cd in samples from Aswan area; and regional variations extending up to factors of 6.5, 3.6, 4.7, 5.9, 4.4, 4.5 and 1.9 for Co, Cr, Cs, Mn, Mo, W and Zn, respectively. No unified relationship is observed between the elemental compositions of hair and nail. For Cr, Cs, Fe, Sb and Sc mean values for hair are lower than in nails. Among the remaining elements the ratio nail/hair is less than 1 for Ag in Assiut, El Kharga and Alexandria, for Cd in all of the areas with the exception of Aswan, for Co, Mn and Mo in Cairo, for Zn in Cairo and Alexandria, and for W in Alexandria. The data for water samples reflect highest concentration of all the measured elements in the Mediterranean sea; a steady increase of the concentration of Cu in drinking water from south to north and for Nile water a similar trend for Ca and Mg; and elevated concentrations of Sb and Mn in river water. No distinct trend for the interrelationship between water and tissue elemental concentrations could be established for the regions around Cairo, Aswan and Alexandria.

Inhibition of desaturation of palmitic, linoleic and eicosa-8,11,14-trienoic acids in vitro by isomeric cis-octadecenoic acids

The effects of the positional isomers of cis-18 : 1 acids on the desaturation of 18 : 2 omega 6 leads to 18 : 3 omega 6 (delta 6 desaturase), 20 : 3 omega 6 leads to 20 : 4 omega 6 (delta 5 desaturase) and 16 : 0 leads to 16 : 1 (delta 9 desaturase) were investigated using essential fatty acid deficient rat liver microsomes. The isomeric cis-18 : 1 acids were found to be inhibitory for the delta 6, delta 5 and delta 9 desaturases, and the position of the double bond is important in determining the degree of inhibition. The effects of the several cis-18 : 1 isomers on delta 6 and delta 5 desaturases were parallel in magnitude exept for the cis-delta isomer which gave 17.5% inhibition for delta 6 desaturase and no inhibition for delta 5 desaturase. The strongest inhibitor for delta 6 desaturase (cis-delta 8 18 : 1) was also the most potent inhibitor for delta 5 desaturase, and the weakest inhibitor for delta 6 desaturase (cis-delta 3 18 : 1) was the least effective inhibitor on delta 5 desaturase. The delta 9 desaturase was maximally inhibited by cis-delta 10 and delta 11 18 : 1 isomers. The cis-18 : 1 acid isomers in partially hydrogenated edible fats may have effects on the lipid metabolism through their inhibitory effects on the desaturases.

Immune deficiency in Hodgkin and non-Hodgkin lymphoma

Forty-three previously untreated Egyptian patients with Hodgkin's disease and thirty-five patients with non-Hodgkin lymphoma were studied with several readily available tests of immune function, number of peripheral blood lymphocytes, delayed hypersensitivity to two recall antigens, in vitro blastoid transformation by PHA, the capacity of E-rosette formation and surface marker criteria. The results were correlated to the histology, stage of disease and to the presence of general symptoms and signs.

Effect of some central nervous system acting drugs on rat brain and liver monoamine oxidase activity

A number of central nervous system acting drugs were administered to male rats. At certain time intervals after the administration of these drugs, the rats were sacrificed. Liver and brain monoamine oxidase (MAO) activities were determined. The drugs employed were: ethyl alcohol, cognac, hexobarbital, diazepam, imipramine and chloralose. Results obtained indicated that the liver MAO activity was not altered by any of these drugs. Brain MAO activity, contrary to in vitro studies, was increased by alcohol and cognac. The increase was not due to a direct effect of alcohol on the enzyme activity, since the in vitro addition of equivalent concentrations of alcohol, as those calculated to be present in vivo, to brain homogenates resulted in a decrease rather than an increase in activity.

Birth weight in relation to maternal socio-economic status

On an attempt to illustrate the influence of maternal socio-economic status on birth weight, this study was carried out on 689 full term new borns. The weight, age, parity, income and occupation of their mothers were compared to the birth weight. A correlation was also performed between birth weight and the presentation of the babies and the ante-natal care offered to their mothers. A positive correlation was only found to be present between birth weight and family income below 10 pounds/month. A similar correlation was noticed between birth weight and the interpregnancy interval up to 30 months. The presentation of the foetus might be of influence on birth weight only in cephalic and breeck presentation. The age of the mother, occupation, weight were negatively correlated with birth weight.

Value of serum copper measurement in acute leukaemia of childhood

Serum copper level (SCL) determination was carried out on sixteen normal children and on 16 with acute leukaemia. A significant increase in SCL was observed in cases of leukaemia than in normal controls. Drop of SCL occurs in cases who respond to quadruple chemotherapy, while those who failed to respond showed persistantly high serum copper level.

Effect of hashish on brain gamma aminobutyric acid system, blood fibrinolytic activity and glucose and some serum enzymes in the rat

Adult male rats were exposed to Hashish smoke for 15 min. Certain biochemical parameters were determined. This treatment did not change the brain glutamic acid level, whereas it significantly decreased brain gamma aminobutyric acid level. There was a significant increase in the activity of the brain enzyme forming gamma aminobutyric acid, namely glutamate decarboxylase, as well as in that enzyme metabolizing gamma aminobutyric acid, namely aminobutyrate aminotransferase. However, the increase was much more marked in the case of aminobutyrate aminotransferase, a finding that might explain the decrease observed in brain gamma aminobutyric acid upon exposure to Hashish. Blood glucose and fibrinolytic activity were significantly increased. It was concluded that these changes might be due to an adrenaline releasing effect of Hashish smoke inhalation. Serum lactate dehydrogenase and serum glutamate oxalacetate transaminase activities were significantly increased, whereas serum glutamate pyruvate transaminase activity was unaffected. From these data it was suggested that the source of leakage of these enzyme activities into the blood is probably the skeletal muscles rather than the liver.

Intra-hepatic vascular response to sodium nitrite

1. In the perfused liver of the dog, sodium nitrite produced vasoconstriction in the hepatic arterial bed and, particularly, in the portal venous vascular bed.2. These effects on the hepatic vasculature may account in part for the reduction of venous return and diminution in cardiac output recorded by other workers, and may therefore be a factor in the clinical efficacy of the nitrites in angina pectoris.