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Biomedical subjects

M M Omar

Publications and source records attributed to M M Omar.

At least 19 recordsLinked to original sources
PubMed2006

Preparation and spectroscopic characterization of novel cyclodiphosph(V)azane of N(1)-2-pyrimidinylsulfanilamide complexes. Magnetic, thermal and biological activity studies.

Hexachlorocyclophosph(V)azane of sulfadiazine, (sulfupyrimidine) [N(1)-2-pyrimidinylsulfanilamide] (H2L1), was prepared and reacted with sulfur and glycine to give (H2L2) and (H2L3) ligands, respectively. The prepared ligands; H2L1, H2L2 and H2L3, react in 1:2 [ligands]:[metal ions] molar ratio with transition metals to give coloured complexes in a relatively good yields. The complexes were characterized using different physicochemical techniques, namely elemental analyses, IR, UV-vis, mass, 1H NMR, molar conductance, magnetic, solid reflectance and thermal analysis. The spectral data reveal that all the ligands behave as neutral bidentate ligands and coordinated to the metal ions via pyrimidine-N and enolic sulfonamide OH. The molar conductance data reveal that the complexes are non-electrolytes while UV-vis, solid reflectance and magnetic moment data have been shown that the complexes have octahedral geometry. The thermal behaviour of the complexes is studied and the thermodynamic activation parameters are calculated. The ligands and their complexes show high to moderate bactericidal activity.

Bacteria↗
PubMed2005

Synthesis, characterization and biological activity of some transition metals with Schiff base derived from 2-thiophene carboxaldehyde and aminobenzoic acid.

Metal complexes of Schiff base derived from 2-thiophene carboxaldehyde and 2-aminobenzoic acid (HL) are reported and characterized based on elemental analyses, IR, 1H NMR, solid reflectance, magnetic moment, molar conductance and thermal analysis (TGA). The ligand dissociation as well as the metal-ligand stability constants were calculated pH metrically at 25 degrees C and ionic strength mu=0.1 (1M NaCl). The complexes are found to have the formulae [M(HL)2](X)n.yH2O (where M=Fe(III) (X=Cl, n=3, y=3), Co(II) (X=Cl, n=2, y=1.5), Ni(II) (X=Cl, n=2, y=1) and UO2(II) (X=NO3, n=2, y=0)) and [M(L)2] (where M=Cu(II) (X=Cl) and Zn(II) (X=AcO)). The molar conductance data reveal that Fe(III) and Co(II), Ni(II) and UO2(II) chelates are ionic in nature and are of the type 3:1 and 2:1 electrolytes, respectively, while Cu(II) and Zn(II) complexes are non-electrolytes. IR spectra show that HL is coordinated to the metal ions in a terdentate manner with ONS donor sites of the carboxylate O, azomethine N and thiophene S. From the magnetic and solid reflectance spectra, it is found that the geometrical structure of these complexes are octahedral. The thermal behaviour of these chelates shows that the hydrated complexes losses water molecules of hydration in the first step followed immediately by decomposition of the anions and ligand molecules in the subsequent steps. The activation thermodynamic parameters, such as, E*, DeltaH*, DeltaS* and DeltaG* are calculated from the DrTG curves using Coats-Redfern method. The synthesized ligands, in comparison to their metal complexes also were screened for their antibacterial activity against bacterial species, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus pyogones and Fungi (Candida). The activity data show that the metal complexes to be more potent/antibacterial than the parent Schiff base ligand against one or more bacterial species.

4-Aminobenzoic Acid↗
PubMed2005

Potentiometric, spectroscopic and thermal studies on the metal chelates of 1-(2-thiazolylazo)-2-naphthalenol.

The synthesis and characterization of Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Pd(II) and UO2(II) chelates of 1-(2-thiazolylazo)-2-naphthalenol (TAN) were reported. The dissociation constants of the ligand and the stability constants of the metal complexes were calculated pH-metrically at 25 degrees C and 0.1 M ionic strength. The solid complexes were characterized by elemental and thermal analyses, molar conductance, IR, magnetic and diffuse reflectance spectra. The complexes were found to have the formulae [M(L)2] for M = Mn(II), Co(II), Ni(II), Zn(II) and Cd(II); [M(L)X].nH2O for M = Cu(II) (X = AcO, n = 3), Pd(II) (X = Cl, n = 0) and UO2(II) (X = NO3, n = 0), and [Fe(L)Cl2(H2O)].2H2O. The molar conductance data reveal that the chelates are non-electrolytes. IR spectra show that the ligand is coordinated to the metal ions in a terdentate manner with ONN donor sites of the naphthyl OH, azo N and thiazole N. An octahedral structure is proposed for Mn(II), Fe(III), Co(II), Ni(II), Zn(II), Cd(II) and UO2(II) complexes and a square planar structure for Cu(II) and Pd(II) complexes. The thermal behaviour of these chelates shows that water molecules (coordinated and hydrated) and anions are removed in two successive steps followed immediately by decomposition of the ligand molecule in the subsequent steps. The relative thermal stability of the chelates is evaluated. The final decomposition products are found to be the corresponding metal oxides. The thermodynamic activation parameters, such as E*, delta H*, delta S* and delta G* are calculated from the TG curves.

Azo Compounds↗
PubMed1998

Immediate endoscopic injection therapy of bleeding oesophageal varices: a prospective comparative evaluation of injecting materials in Egyptian patients with portal hypertension.

The present study was conducted to compare usual sclerosants: polidocanol 1%, ethanolamine oleate 5% and the tissue adhesive: cyanoacrylate in the control of oesophageal variceal bleeding in Egyptian patients with portal hypertension in a prospective comparative trial. Sixty patients with portal hypertension due to schistosomal hepatic fibrosis and/or posthepatitic liver cirrhosis who had presented with acute oesophageal variceal bleeding were enrolled. Patients received balloon tamponade prior to injection were excluded. Resuscitation had been done before or during emergency endoscopy. Emergency endoscopy was conducted within 2 hours from the onset of hematemesis. Patients were immediately randomized during emergency endoscopy to receive polidocanol 1%, ethanolamine oleate 5% or tissue adhesive. Variceal rebleeding was managed by reinjection. The three groups were comparable for age, sex, etiology of portal hypertension, Child-Pugh class and findings at emergency endoscopy. No active bleeding was observed at the end of all injection sessions. Rebleeding had been occurred within the first 24 hours in 2 (10%) patients in polidocanol group and 3 (15%) patients in ethanolamine group (P > 0.05). Reinjection did control rebleeding in 2 (10%) patients in ethanolamine group with a total success rate of 95%. Exsanguinating rebleeding occurred in 2 (10%) patients in polidocanol group and one (5%) patient in ethanolamine group (P > 0.05). Postinjection large ulcers were diagnosed either in polidocanol (15%) or ethanolamine (10%) groups (P > 0.05). Other complications were minor and showed no significant differences between the three groups. In coclusion, polidocanol, ethanolamine and cyanoacrylate are equally safe and effective. For immediate endoscopic injection therapy an experienced team must be available.

Cyanoacrylates↗
PubMed1997

One-hundred and five new potential Drosophila melanogaster genes revealed through STS analysis.

Complementation analysis had suggested that the Drosophila melanogaster genome contains approximately 5000 genes, but it is now generally accepted that the actual number is several times as high. We report here an analysis of 1788 anonymous sequence tagged sites (STSs) from the European Drosophila Genome Project (EDGP), totalling 463 kb. The data reveal a substantial number of previously undescribed potential genes, amounting to 6.1% of the number of Drosophila genes already in the sequence databases.

Amino Acid Sequence↗
PubMed1997

Excess female mortality in rural Somalia--is inequality in the household a risk factor?

Gender differences in mortality risks in rural Somali communities were studied to assess their relation to literacy, marital status and family economy between January 1987 and December 1989. In all, 6947 person-years form the basis for the demographic analysis and estimations of mortality rates and survival. Both sexes showed similar mortality risks in infancy and early childhood, but females demonstrated a greater risk of dying during their reproductive life than males. Respiratory symptoms, diarrhoea, fever and jaundice dominated the symptoms prior to death Illiteracy in women considerably increased the risk of dying from 15 years and onwards particularly when living with literate men. The life expectancy from 15 years was 58 for a literate male but only 42 years for an illiterate woman living with a literate head of household. Multivariate analyses showed after adjustment for marital status and literacy that an excess female mortality from 15 years, but especially from 45 years, was associated to a household situation, where the woman did not subside on farming but on other, mainly commercial, activities. This vulnerability of females was associated to the recession of the economy in the pre-war situation in Somalia, a backlash hitting women trying to earn their living. To conclude, gender differences in a number of factors in the household-literacy, marital status and especially source of income-were disadvantageous for the women, increasing the mortality risk in this setting.

Adolescent↗
PubMed1997

P-element insertion alleles of essential genes on the third chromosome of Drosophila melanogaster: correlation of physical and cytogenetic maps in chromosomal region 86E-87F.

We have established a collection of 2460 lethal or semi-lethal mutant lines using a procedure thought to insert single P elements into vital genes on the third chromosome of Drosophila melanogaster. More than 1200 randomly selected lines were examined by in situ hybridization and 90% found to contain single insertions at sites that mark 89% of all lettered subdivisions of the Bridges' map. A set of chromosomal deficiencies that collectively uncover approximately 25% of the euchromatin of chromosome 3 reveal lethal mutations in 468 lines corresponding to 145 complementation groups. We undertook a detailed analysis of the cytogenetic interval 86E-87F and identified 87 P-element-induced mutations falling into 38 complementation groups, 16 of which correspond to previously known genes. Twenty-one of these 38 complementation groups have at least one allele that has a P-element insertion at a position consistent with the cytogenetics of the locus. We have rescued P elements and flanking chromosomal sequences from the 86E-87F region in 35 lines with either lethal or genetically silent P insertions, and used these as probes to identify cosmids and P1 clones from the Drosophila genome projects. This has tied together the physical and genetic maps and has linked 44 previously identified cosmid contigs into seven "super-contigs" that span the interval. STS data for sequences flanking one side of the P-element insertions in 49 lines has identified insertions in the alphagamma element at 87C, two known transposable elements, and the open reading frames of seven putative single copy genes. These correspond to five known genes in this interval, and two genes identified by the homology of their predicted products to known proteins from other organisms.

Alleles↗
PubMed1997

Endoscopic control of gastric variceal bleeding with butyl cyanoacrylate in patients with schistosomiasis.

This trial represents the Egyptian experience in cyanoacrylate injection for hemostasis of bleeding gastric varices. One hundred patients with portal hypertension due to schistosomal hepatic fibrosis and/or posthepatitic liver cirrhosis were included. All patients presented with bleeding from gastric varices either fundal (80 patients) or inferior extension of esophageal varices (20 patients) were enrolled. Injection therapy was administered as the first active measure. No tamponade or drugs were used. Cyanoacrylate was mixed with lipid and injected through a hand-made probe. A mean of 3 (range 1-9) ampoules of cyanoacrylate were used per injection session. Bleeding stopped at the end of all sessions. Ten patients (12.5%) with fundal varices had rebleeding during the first 24 hours. Reinjection could control bleeding in 6 patients with a total success rate of 95%. Four patients were managed surgically. Fatal pulmonary embolism developed in one patient (1.25%) with fundal varix. Five more patients (6.25%) died from bleeding-related liver failure. In conclusion, injection of cyanoacrylate is highly satisfactory in controlling bleeding from both types of gastric varices.

Adult↗
PubMed1997

Helicobacter pylori among Egyptian patients with chronic liver diseases. A comparative study.

The prevalence of Helicobacter pylori in Egyptian patients with different stages of liver diseases was compared to those with normal liver status. Eighty patients subjected to upper gastrointestinal endoscopy were enrolled. They were divided according to their liver status into two groups; the first patients with liver cirrhosis and the second who had no liver affection. Gall bladder diseases were excluded by abdominal ultrasound examinations. Endoscopic antral mucosal biopsies were used for H. pylori screening by both culture and urease test, and for histopathological examinations. Both groups were matched as regards age, sex, and socioeconomic conditions. Culture was positive in 42.2% and 40.7% of patients in both groups respectively (P > 0.05). Urease test showed positive results in 58% and 76.6% in both groups respectively (P > 0.05). Helicobacter pylori prevalence showed no significant differences between both studied groups as regards age, sex, or type of gastric lesions. Furthermore, liver status in patients with chronic liver diseases does not play a role in distribution of infection. The study shows the high prevalence of H. pylori among Egyptians and the absence of a relation between H. pylori and chronic liver diseases.

Adult↗
PubMed1994

Maternal health and child survival in relation to socioeconomic factors.

The health of 280 rural Somali women of reproductive age was studied using a structured questionnaire, measuring weight, height, arm circumference and estimations of hemoglobin. Mean height and weight were 159 cm and 53 kg, respectively. 12.7% had a weight below 50 kg and 5.6% had a height below 150 cm. One third of the women had a body mass index of 19 indicating sub/malnutrition. Mean hemoglobin was 105 g/l. Every fourth woman had a hemoglobin level between 85 and 100, while every tenth had a value below 70 g/l. A higher hemoglobin level and better child survival rate were associated with the husband's reading ability, whether the household owned a farm, whether the woman had a second job, whether the woman possessed gold and the household's possession of a radio.

Adult↗
PubMed1994

Fertility, infertility and child survival of Somali women.

The relationship of reproductive patterns, some socio-economic factors and child survival was studied in 766 rural Somali women. A structured questionnaire was the method of data collection. Teenage marriage was the norm for the women, and divorce was very common. The mean number of live births was 5.2, and the mean number of surviving children was 3.7. 2/3 of the women aged 45+ had a parity of 6 or more, about one third had had at least one miscarriage and one fifth had experienced one stillbirth. Primary infertility was observed in 7% of the women aged 45+, while 20% were considered subfertile. Verbal autopsy showed that mortality was highest among infants and accounted for 63% of the child deaths. Major causes of death were neonatal tetanus, diarrhoea and respiratory diseases. Child survival and reproductive outcome ratios were found to be negatively related to the increasing age of the mother and parity. Divorce and widowhood were also found to be associated with low child survival.

Abortion, Spontaneous↗
PubMed1987

Fractionation of proteins in reconstituted skim-milk.

Properties of the dried milk were improved when calcium chloride was added to the raw milk prior to the drying process. Solubility, wettability, undenatured whey protein and protein retention indices of the dried milk were increased and the reconstitutability was improved. The elution profile of the protein fractions on a Sephadex G-100 column differed according to the forward preheating of the raw milk and the addition of calcium chloride.

Animals↗
PubMed1985

Size distribution of casein micelles during milk coagulation.

Electron microscopy was employed to study the size distribution and the surface to volume ratios of casein micelles in coagulum from raw milk, heated milk and milk enriched with calcium chloride before the heating process. The particles size distribution of milk protein was changed by heating resulting in an increase in the free subunits of smaller size and the surface to volume ratios. On the other hand the clotting time was prolonged. Depression in the clotting time and surface to volume ratios was occurred by adding calcium chloride to the milk before the heating process to retard the formation of complex between the whey protein and milk casein.

Animals↗
PubMed1982

Hypothalamic-pituitary function following bromocriptine therapy in patients with prolactinomas.

Bromocriptine in a dose of 5 mg daily was given to 18 patients with prolactinomas to promote resumption of menses, to overcome infertility and as a primary treatment for the tumor. Serum prolactin levels fell to within the normal range in 95% of the patients by 12 weeks of therapy. The prolactin response to TRH stimulation was significantly less than before treatment; however, the percent maximum increment was significantly higher. There was no significant change in pituitary reserve of the other hormones. Seven pregnancies occurred during treatment. All the pregnancies have been progressing normally. All patients have already been delivered of healthy babies, including one set of twins. It is suggested that follow-up studies of the various pituitary hormones be conducted on patients on maintenance bromocriptine treatment. In addition, bromocriptine treatment might be used to promote fertility in patients with prolactin-secreting microadenomas.

Adenoma↗