44 research outputs found
Value of duplex scanning in differentiating embolic from thrombotic arterial occlusion in acute limb ischemia
No full textCRT-100.12 Temporal Changes in the Management of Acute Coronary Syndromes Over The Years, Egyptian Experience
No full textObesity and follicular fluid oxidative stress: Relationship to ICSI outcome
No full textObjective: To study the influence of female obesity on follicular fluid oxidative stress and to correlate it to intracytoplasmic sperm injection (ICSI) outcome.
Study design: Seventy-four normal females below the age of 40 undergoing ICSI for reason of male factor infertility were enrolled in the study. They were divided into 2 groups according to body mass index (BMI); Group I (non-obese) (n = 24, BMI < 25 Kg/m2) and Group II (obese) (n = 50, BMI ⩾ 25 Kg/m2). Oxidative stress markers (MDA (malonaldehyde), NO2/NO3 (Nitrite/Nitrate) ratio, GSH (reduced glutathione) and GSH/GSSG (reduced glutathione/oxidized glutathione) ratio) were measured by high performance liquid chromatography (HPLC).
Results: Obese women had significantly higher mean follicular fluid MDA (P = 0.006) as well as NO2/NO3 ratio (P = 0.004). BMI strongly correlated to follicular fluid MDA (P = < 0.01). MDA showed strong positive correlation to NO2/NO3 ratio (P = 0.02). GSH and GSH/GSSG ratio showed a non-significant difference between the two groups (P = 0.14 and 0.67, respectively). Clinical pregnancy rate was significantly higher in the non-obese group (87%) compared to the obese (43%) (P = <0.01, OR:13; 95% CI 3.54–52). With binary logistic regression, MDA was found to be a good predictor of the occurrence of pregnancy (P = <0.01). No significant differences were detected as regards parameters including estradiol on day of hCG, gonadotropin dose, number of retrieved oocytes, metaphase II(MII) and fertilized oocytes.
Conclusion: Obesity aggravates follicular fluid oxidative stress with a negative impact on pregnancy outcome of ICSI cycles
Seasonal variations of hydration status of professional soccer players in Saudi Arabia during training sessions and match play
No full textSoccer is the most widely played sport in the world. Consequently, players train and compete in a wide variety of environmental conditions. Professional soccer players normally train daily and compete once or twice a week. Exercise hot environments can lead to dehydration because sweat losses often exceed fluid intake. Sweat rate can range between 1 to 2.5 L.h-1 depending on factors such as environment conditions, fitness and clothing. Previous studies of soccer players have found that players are often dehydrated.
This thesis consists of three studies conducted in Riyadh, Saudi Arabia. Young Saudi professional soccer players based at the Al Hilal club were recruited to the study. The author worked them during their training and matches at different periods during the year to study the effects of exercise in warm and cool conditions. Their hydration status was studied using a range of methods including analysis of the blood and urine. The main aims of these experiments were to examine the effect of exercise intensity in temperate and hot environments on blood, urine, core body temperature and aldosterone concentrations.
The first study evaluated their hydration status over three days of training and one match in temperate conditions. The aim of this study was to establish that research could be conducted as players went through their normal routines determined by the club management and coaches. Change in body weight, serum osmolality and electrolytes, sweat loss, fluid intake and aldosterone concentrations were measured. The range of ambient temperatures was between 23.4 and 30.6 oC and the relative humidity ranged between 14.2 and 23.2 %. Eleven Saudi professional soccer players participated in this study. Their body weight significantly decreased during exercise. Serum osmolality was always high indicating dehydration. It increased significantly during match play, from pre 288 ± 3 mOsm/kg to 293 ± 4 mOsm/kg. Day by day changes of serum osmolality before training sessions and match were small and on some days statistically significant. Plasma aldosterone concentrations significantly increased after the match. The magnitude of dehydration was affected by the intensity of the training sessions GPS was used to measure distance covered. Players covered more distance in match play (7326 m) than in training sessions. Core body temperature was elevated during exercise but not to dangerous levels.
The second study was aimed to repeat these measurements in the summer time during the early season in September. Again, three training sessions and one match were studied. The environment conditions were above 35 oC on all days and the relative humidity was between 10.5 and 13.0 %. The success of the first study in establishing a good relationship allowed some expansion and sixteen soccer players were recruited. Similar results were obtained and fluid losses were greater in the hotter conditions. None of the players replaced all of the fluid lost in training sessions or match play. The mean of sweat rate was 1932 ± 512 ml.h-1 and players dehydrated by 1.8 ± 0.7 % during match play. The serum sodium concentrations were small but statistically significant for some sessions. Similar changes were seen in serum osmolality. Estimated urine osmolality and specific gravity values were high on all days. Plasma aldosterone concentrations increased significantly during two training sessions and match play. On all days the mean of core temperature during exercise increased significantly.
The third study aimed to improve hydration in a group of players before they started training. Responses were compared in hydration intervention (HI) and hydration control (HC) groups. Each group comprised of eight soccer players. The ambient temperature during this study was about 29 oC. Measurements were taken on three days; the first day was as base line. Next two days, intervention group were instructed to consume 500 ml before attending the club. Independent t-test showed no significant differences between the two groups in base line of age, body weight, height and BMI (P > 0.05). Blood, urine, intensity of exercise, aldosterone and core body temperature were measured between groups. Serum electrolyte concentrations were not different in the two groups on three days. The serum osmolality of HI was significantly lower than HC before training two (T2) during the study (P < 0.05). No differences in fluid intake were observed during training and sweat rate and loss did not differ during training sessions in the two groups. In addition, serum osmolality did not change after T2 in HI, where the control group had significant increase in osmolality after this training session (P < 0.05). On the third day, serum osmolality did not differ between the two groups. However, after exercise serum osmolality elevated from pre to post exercise. The HI group had lower aldosterone concentrations before T2 started than HC group (P < 0.05). The core temperatures rose during exercise in both groups and there were no differences between the two groups.
In conclusion, the three studies were completed successfully. Good data were obtained and it was possible to conduct research with the players as they followed their normal routines of training and playing. These data showed that the players were dehydrated before and during training and match play. Sweat loss was greater in hot conditions than in temperate conditions. Serum osmolality elevated after exercise in hot and temperate conditions and by different intensity of exercise. Plasma aldosterone concentrations were affected by the exercise in all studies
Why articles continue to be cited after they have been retracted : An audit of retraction notices
No full textBackground: Papers continue to be cited by authors even after they have been retracted. Retraction notices provide readers with information about retracted papers and may help minimise post-retraction citation. To date, a review of the quality of retraction notices in nursing science has not been reported. Design: An audit of retraction notices associated with 29 retracted manuscripts published in nursing science journals. Methods: Retraction notices were reviewed again using the Committee on Publication Ethics (COPE) guidelines. Results: In total, 28 retraction notices were retrieved and reviewed (one retracted paper did not have a retraction notice). Details of the retracted manuscripts were included in all reviewed notices and, in all but two, author names were reported. Details of the time between a paper being published and retracted were not reported and generally there was a little information in notices about how the retraction decisions were made. All retraction notices were freely available. Seven notices stated who had made the decision to retract. Twenty-two (77%) notices stated the reason for retraction. Notices were brief and contained factual information. The webpages of three retracted articles did not clearly indicate that the paper had been retracted. Conclusion: More detailed and informative retraction notices will inform readers and may help reduce post- retraction citation
Enhancing lignite coal quality with biomass waste in slow pyrolysis Fischer-Tropsch reactor
No full textCoal is a non-renewable natural resource that is widely used in thermal power plants in major industrialized countries. Most of the world's coal contains a high percentage of moisture and ash and a low caloric value. The slow pyrolysis process of coal improves its quality and significantly reduces its smoke and ash. In this study, Soma Kisrakdere lignite coal in Manisa province in Turkey with some biomass wastes (peanut shells, pine cones, and olive seeds) was evaluated by applying a slow pyrolysis process using a Fischer-Tropisch reactor. Firstly, Soma Kisrakdere lignite alone, then each waste biomass was mixed with lignite coal at weight percentages of 10 %, 25 %, and 50 % to form three mixtures for each biomass waste. The process temperature was 500°C, and the temperature rate was 0.1 °C/s. The findings obtained in this study showed that with the increase of weight percentages of biomass which added from biomass waste to lignite coal, the productivity of coal (biochar) decreased and the products of tar, decomposed water, and gases increased. As for calories, its value increased with the increase in weight of the addition the waste of biomass which added where 50 % of biomass additions were the highest value of low heating value (LHV) and high heating value (HHV) and most effective than others which added to lignite coal. Among the biomass residues used, the olive seeds were the most valuable, compared with the peanut shells and pine cones. © 2024 The Author
Recent Advances in Stem Cell Therapy for Limbal Stem Cell Deficiency: A Narrative Review
No full text\ua9 2020, The Author(s). Destruction of the limbus and depletion of limbal stem cells (LSCs), the adult progenitors of the corneal epithelium, leads to limbal stem cell deficiency (LSCD). LSCD is a rare, progressive ocular surface disorder which results in conjunctivalisation and neovascularisation of the corneal surface. Many strategies have been used in the treatment of LSCD, the common goal of which is to regenerate a self-renewing, transparent, and uniform epithelium on the corneal surface. The development of these techniques has frequently resulted from collaboration between stem cell translational scientists and ophthalmologists. Direct transplantation of autologous or allogeneic limbal tissue from a healthy donor eye is regarded by many as the technique of choice. Expansion of harvested LSCs in vitro allows smaller biopsies to be taken from the donor eye and is considered safer and more acceptable to patients. This technique may be utilised in unilateral cases (autologous) or bilateral cases (living related donor). Recently developed, simple limbal epithelial transplant (SLET) can be performed with equally small biopsies but does not require in vitro cell culture facilities. In the case of bilateral LSCD, where autologous limbal tissue is not available, autologous oral mucosa epithelium can be expanded in vitro and transplanted to the diseased eye. Data on long-term outcomes (over 5 years of follow-up) for many of these procedures is needed, and it remains unclear how they produce a self-renewing epithelium without recreating the vital stem cell niche. Bioengineering techniques offer the ability to re-create the physical characteristics of the stem cell niche, while induced pluripotent stem cells offer an unlimited supply of autologous LSCs. In vivo confocal microscopy and anterior segment OCT will complement impression cytology in the diagnosis, staging, and follow-up of LSCD. In this review we analyse recent advances in the pathology, diagnosis, and treatment of LSCD
Determination of polycyclic aromatic hydrocarbon content in heat-treated meat retailed in Egypt: Health risk assessment, benzo[a]pyrene induced mutagenicity and oxidative stress in human colon (CaCo-2) cells and protection using rosmarinic and ascorbic acids
No full textThis study was undertaken to estimate the concentrations of the formed polycyclic aromatic hydrocarbons (PAHs) in heat-treated (boiled, pan-fried and grilled) meats collected from Egypt. Dietary intakes and cancer risks of PAHs among Egyptian adults were calculated. Benzo[a]pyrene (B[a]P)-induced mutagenicity and oxidative stress in human colon (CaCo-2) cell line and mechanisms behind such effects were also investigated. Finally, protection trials using rosmarinic (RMA) and ascorbic acids (ASA) were carried out. The results indicated formation of PAHs at high levels in the heat-treated meats. Calculated incremental life time cancer risk among Egyptian adults were 7.05179E - 07, 7.00604 E - 06 and 1.86069 E - 05 due to ingestion of boiled, panfried and grilled meats, respectively. B[a]P-exposed CaCo-2 cells had high abilities for mutagenicity (490.05 +/- 21.37 His + revertants) and production of reactive oxygen species. RMA and ASA protected CaCo-2 cells via reduction of B[a]P-induced mutagenicity and oxidative stress and upregulation of phase II detoxification enzymes and xenobiotic transporters
Timing of salicylic acid application affects the response of maize (Zea mays L.) hybrids to salinity stress
No full textThe effect of genotype and timing of salicylic acid (SA) application on response of maize to salinity stress has been investigated. Single and triple hybrids (SH and TH, respectively) of maize were grown hydroponically and sprayed with 1 mM SA one week either before or after application of 150 mM NaCl. The effect of salinity on maize performance was stronger than that of SA regime or maize hybrid. The effect of treatments was most evident on root biomass but least evident on number of leaves. The genotypic difference in shoot biomass was vague in non-amended plants but emerged, in favor of the SH, in SA-amended plants. The more vigorous SH exhibited less pigment content (particularly the post-amended plants) and less salt resistance, with preferential native allocation of plant biomass to root compared with the TH. Salicylic acid, particularly the post amendment under salinity stress, was stressful to maize foliage but beneficial to roots. Salinity reduced root growth to a greater extent than shoot growth, with the production of wider and shorter blades; but SA led to the opposite effect. The effect of salinity on leaf chlorophyll a concentration was non-significant in the SH, versus an increase (in the post-amended plants) or a decrease (in the non-amended and pre-amended plants) of the TH. Sub-stomatal CO2 concentration (Ci) was higher in the SH than the TH, particularly in the post-amended plants. Both salinity and SA induced stomatal closure, reduced rates of transpiration and photosynthesis but increased Ci, with variable magnitudes in the two hybrids. Salinity increased concentrations of soluble sugars, proline and Na+ in the leaves, decreased K+ and phenolics concentrations but marginally affected protein concentration with limited effect of SA, which varied according to time of application. The further stressing effect of SA post-amendment to salt-stressed maize can be related to reduced stomatal conductance and concentrations of phenolics, proline and K+ but increased Na+ concentration of the shoot, particularly of the TH
Coronary artery ectasia: prevalence, clinical and angiographic characteristics using multislice computed tomography coronary angiography
No full text
