PubMed Health⌕ Search

Biomedical subjects

M Metwally

Publications and source records attributed to M Metwally.

10 recordsLinked to original sources

Fluid and pharmacological agents for adhesion prevention after gynaecological surgery.

BACKGROUND: Pelvic surgery is associated with high rates of both de novo adhesion formation and adhesion reformation. Since subsequent fertility is reduced with increasing severity of periadnexal adhesions, pelvic adhesions will remain a clinical problem in infertility patients. Steroids, antihistamines and heparin were amongst the first substances to be advocated for adhesion prevention. More recently icodextrin 4%, hyaluronic acid agents and SprayGel have been used. This review aims to evaluate the role of fluid and pharmacological agents in the prevention of adhesions in fertility-conserving gynaecological surgery. OBJECTIVES: To investigate fluid and pharmacological agents for adhesion prevention when used as adjuvants during pelvic surgery. SEARCH STRATEGY: This review has drawn on the search strategy developed for the Menstrual Disorders and Subfertility Group. The following databases were searched: the Cochrane Menstrual Disorders and Subfertility Group Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE. SELECTION CRITERIA: Randomised controlled trials investigating the use of fluid and pharmacological agents to prevent adhesion formation after fertility-conserving gynaecological surgery. DATA COLLECTION AND ANALYSIS: Data extraction and analysis was performed independently by two authors (Metwally M and Watson A). Two-by-two tables were generated for dichotomous outcomes and expressed as odds ratios (OR) with 95% confidence intervals (CI). For continuous outcomes a standardised mean difference was used. MAIN RESULTS: There is no evidence of benefit from the use of steroids, dextran or other pharmacological agents in any of the outcomes. The use of hyaluronic acid agents may decrease adhesion formation (OR 0.31, 95% CI 0.19 to 0.51) and prevent the deterioration of pre-existing adhesions (OR 0.28 (95% CI 0.12 to 0.66). There is insufficient evidence for the use of icodextrin 4% or SprayGel as adhesion-preventing agents. None of the studied agents has been shown to improve the pregnancy rate when used as an adjunct during pelvic surgery. AUTHORS' CONCLUSIONS: The current evidence for the use of fluid and pharmacological agents for the prevention of adhesions is limited. There is no evidence on any benefit for improving pregnancy outcomes when pharmacological and fluid agents are used as an adjunct during pelvic surgery. There is insufficient evidence for the use of the following agents: steroids, icodextrin 4%, SprayGel and dextran in improving adhesions following surgery. There is some evidence that hyaluronic acid agents may decrease the proportion of adhesions and prevent the deterioration of pre existing adhesions. However, due to the limited number of studies available, this evidence should be interpreted with caution and further studies are needed.

Anticoagulants↗

Fungal fermentation of whey incorporated with certain supplements for the production of proteases.

The pattern and the extent of formation of proteases and secretion varied with the fungus, age and/or the nature of the co-supplement. Addition of yeast extract induced the best yield of proteases from both Aspergillus niger and A. terreus. Proteases from A. niger were highly induced by glutamic acid, alanine or albumin, with minor differences, whereas gelatin, peptone, aspartic acid, casein or acetamide stimulated the accumulation of proteases in the culture medium of A. terreus. Galactose stimulated the yield of the enzyme particularly with A. terreus while most C-supplements inhibited such processes, more prominently in the presence of cellulose or starch. Incorporation of nicotinic acid and wheat bran initiated the maximum productivity of proteases from A. niger and A. terreus, respectively. Co+2 and Cu+2 highly stimulated the output of proteases from A. niger and A. terreus, respectively. Co+2 and Ca+2 stimulated the enzyme activity of alkaline and acid proteases from A. terreus and acid proteases from A. niger. The other six cations and DTT inhibited variably the three proteases particularly alkaline proteases from A. terreus indicating that proteases from various sources even from closely related species showed different properties.

Aspergillus↗

Bioenergetic consequences of glucoamylase production in carbon-limited chemostat cultures of Aspergillus niger.

Aspergillus niger has been grown in glucose- and maltose-limited continuous cultures to determine the bioenergetic consequences of the production of the extracellular enzyme glucoamylase. Growth yields (g biomass per mol substrate) were high, indicating that growth was very efficient and protein production for biomass was not exceedingly energy consuming. It has been found that the energy costs for the production of this extracellular enzyme is very high. Depending on the efficiency of energy conservation the glucoamylase protein yield on ATP is between 1.3 and 2.6 g protein per mol ATP, which is equal or less than 10% of the theoretical maximum of 25.5. These high energy costs most probably have to be invested in the process of excretion. A comparison between an industrial over-producing strain and the wild type Aspergillus niger showed that this over-producing strain most probably is a regulatory mutant. Two regions of specific growth rates could be determined (one at specific growth rates lower and one at specific growth rates higher than 0.1 h-1), which are characterized by differences in mycelium morphology and a significant deviation from linearity in the linear equation for substrate utilization. Analysis of the region of specific growth rates higher than 0.1 h-1 yielded maintenance requirements of virtual zero. It has been concluded that for a good analysis of the growth behaviour of filamentour fungi the linear equation for substrate utilization is not suitable, since it contains no term for the process of differentiation.

Adenosine Triphosphate↗

Quantitative evaluation of ECG components of workers exposed to carbon disulfide.

The components of electrocardiograms (ECG) of 253 workers exposed to carbon disulfide (CDS) and those of 99 controls were quantitatively measured and evaluated. ECG of the exposed workers showed a statistically significant higher prevalence of ECG pathological changes, higher P amplitude and Macruz index, longer P duration, longer both crude and corrected Q-T intervals and R-R intervals and shorter P-R segments and QRS intervals than that of the controls. On the other hand, P-R intervals and heart rates of the two groups were not significantly different. Among both the the exposed and control groups, values of P duration were significantly negatively correlated with that of P-R segment: r = -0.216 and -0.132, respectively, p greater than 0.05. Values of the ECG components were not related to duration of exposure to CDS. Moreover, no significant difference was observed between duration of exposure of the exposed workers with and of those without pathological ECG changes. The method used in our study may be useful in evaluating the ECG of exposed workers before the appearance of the known pathological abnormalities.

Adult↗

Determination of the maximum product yield from glucoamylase-producing Aspergillus niger grown in the recycling fermentor.

Aspergillus niger has been grown in glucose- and maltose-limited recycling cultures to determine the maximum growth yield, the maximum product yield for glucoamylase production, and the maintenance requirements at very slow specific growth rates. Using the linear equation for substrate utilization, and using the experimental data from both recycling experiments, both the maximum growth yield, Yxsm, and the maximum product yield, Ypsm, could be determined. The values estimated were 157 g biomass per mol maltose for Yxsm and 100 g protein per mol maltose for Ypsm. Expressed on a C1-basis these values are 0.52 and 0.36 C-mole per C-mol for respectively Yxsm and Ypsm. The found value for Ypsm is half the value found for alkaline serine protease production in Bacillus licheniformis, and it can be concluded that formation of extracellular protein is more energy consuming in filamentous fungi than in prokaryotic organisms. Maintenance requirements are no significant factor during growth of Aspergillus niger, and reported maintenance requirements are most probably due to differentiation.

Aspergillus niger↗