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Biomedical subjects

M A Ahmed

Publications and source records attributed to M A Ahmed.

At least 19 recordsLinked to original sources

Longlasting antalgic effects of daily sessions of repetitive transcranial magnetic stimulation in central and peripheral neuropathic pain.

BACKGROUND AND OBJECTIVE: A single session of repetitive transcranial magnetic stimulation (rTMS) over motor cortex had been reported to produce short term relief of some types of chronic pain. The present study investigated whether five consecutive days of rTMS would lead to longer lasting pain relief in unilateral chronic intractable neuropathic pain. PATIENTS AND METHODS: Forty eight patients with therapy resistant chronic unilateral pain syndromes (24 each with trigeminal neuralgia (TGN) and post-stroke pain syndrome (PSP)) participated. Fourteen from each group received 10 minutes real rTMS over the hand area of motor cortex (20 Hz, 10x10 s trains, intensity 80% of motor threshold) every day for five consecutive days. The remaining patients received sham stimulation. Pain was assessed using a visual analogue scale (VAS) and the Leeds assessment of neuropathic symptoms and signs (LANSS) scale, before, after the first, fourth, and fifth sessions, and two weeks after the last session. RESULTS: No significant differences were found in basal pain ratings between patients receiving real- and sham-rTMS. However, a two factor ANOVA revealed a significant "+/- TMS" x "time" interaction indicating that real and sham rTMS had different effects on the VAS and LANSS scales. Post hoc testing showed that in both groups of patients, real-rTMS led to a greater improvement in scales than sham-rTMS, evident even two weeks after the end of the treatment. No patient experienced adverse effects. CONCLUSION: These results confirm that five daily sessions of rTMS over motor cortex can produce longlasting pain relief in patients with TGN or PSP.

Electromyography↗

Placental pathology in relation to the White's classification of diabetes mellitus.

The objective of this study was to investigate various macroscopic and microscopic features of the placenta in pregnancies complicated by diabetes according to White's classification. A total of 148 placentas were studied. Sixty-five were from control patients and 83 from diabetic mothers. The diabetic mothers were further divided into three groups according to White's classification. There were 40 cases in White's group A and 36 cases in White's group B. There were 7 cases in White's groups C and D combined. Advanced maternal age and grandmultiparity were significantly higher in White A, White B and White C&D compared to the normal group. Mean weight of the mother was higher in White group A and group B compared to the control group and group C&D. The placental weight and neonatal weight were increased provided the diabetes was not complicated by vascular disease. With accompanying vascular disease the placental weight and neonatal weight were reduced compared to the controls. As a result of increased perinatal jeopardy the rate of operative delivery was higher in diabetic mothers. No major difference was observed in microscopic changes of placentas in different groups according to White's classification and the normal group.

Adolescent↗

The status of rubella immunity among pregnant women in Kuwait: screening in childbearing age should be reintroduced.

The objective of this study was to investigate the immunity against rubella in the obstetric population in Kuwait by testing 600 pregnant women at a prenatal clinic, using the haemagglutination inhibition technique. In addition, a comparison was made between this study and one done in 1978 at the same clinic; its relation to the vaccination programme is also discussed. 7.7% of the population under study were non-immune. Statistically significant effect was demonstrated for maternal age but not for parity and nationality. Though it has been almost 20 years since an intense rubella vaccination programme was implemented, the percentage of non-immune pregnant women has not decreased. In Kuwait, termination of pregnancy for congenital rubella syndrome is prohibited. As a result, it is recommended that women be screened and vaccinated at the time of marriage.

Adolescent↗

Familial thrombocytosis as a recessive, possibly X-linked trait in an Arab family.

Familial thrombocytosis (FT) has previously been described as an autosomal-dominant disorder with manifestations similar to those of sporadic essential thrombocythaemia. We studied an Arab family consisting of four brothers, aged 4-8 years, who had either sustained markedly elevated (> 1000 x 109/l) or moderately elevated (> 500 x 109/l) platelet counts, two healthy sisters and their parents who had normal platelet counts. The four brothers with FT had normal plasma thrombopoietin levels and are currently not presenting with any thrombotic or haemorrhagic complications. Mutation analysis at the thrombopoietin gene (THPO) of the affected family members failed to detect the intron 3 G-->C splice mutation that had been described as causing FT. In addition, segregation analysis using a polymorphic CA marker revealed completely discordant THPO alleles among the affected brothers. We postulate the existence of a new locus for FT whereby the disease is transmitted as a recessive, possibly X-linked trait.

Adult↗

Frequency of ABO blood groups in the Eastern region of Saudi Arabia.

OBJECTIVE: To document the frequency of the ABO and Rhesus blood groups in Saudi male donors, and to compare our results with the results of other studies in the Kingdom and elsewhere. METHODS: This study included a total of 57396 male potential blood donors; 19496 blood donors between the years 1985-1989 (referred to as first period of study) and 37700 blood donors between the years 1995-1999 (2nd period). The blood donors were Saudis, coming to donate blood for various reasons to the Blood Bank Department of King Fahd Hospital of the University, Al-Khobar, Kingdom of Saudi Arabia. ABO and Rhesus blood groups from 200 Saudi females were also determined. The frequency of ABO blood groups and Rhesus status were calculated separately. RESULTS: Our results revealed the most common blood group was O, (52%) during the first period of study and likewise the most common blood group (51%) during the 2nd period. The lowest blood group frequency was AB (4%) and (4%) during the first and 2nd period. Rhesus positive blood donors comprised 93% and Rhesus-negative donors were 7% during the first period, while they amounted to 91.5% and 8% during the 2nd period. Overall frequency of ABO and Rhesus blood groups during the 2 periods were the following: O-positive 48% and 46%; A-positive 24% and 24.5%; B-positive, 17% and 17%; AB positive 4% and 4%; O negative 4% and 5%; A negative 2% and 2%; B-negative 1% and 2%; and AB negative, 0.23% and 0.32%. Comparison of our results with the other studies from the Kingdom and other nationalities is also presented. CONCLUSION: Our results show that the most frequent blood group in Saudis is O-positive. Blood group A is observed at a lower frequency relative to values from Western populations, whereas a significant increase in blood group B combined with a slight increase in blood group AB was recorded. Knowledge of the frequencies of the different blood groups in Saudi Arabia is very important for Blood Banks and transfusion service policies. Knowledge of blood group phenotype distribution is also important for clinical studies (for example disease association), as well as for population studies.

ABO Blood-Group System↗

Middle cerebral artery to umbilical artery resistance index ratio in the prediction of neonatal outcome.

OBJECTIVE: The objectives of this study were to evaluate the usefulness of the middle cerebral artery to umbilical artery resistance index ratio (C/U ratio) as a predictor of adverse perinatal outcome, and to show that the absence of fetal umbilical artery end-diastolic velocity (AEDV) in SGA fetuses is associated with high morbidity and mortality. METHOD: In this prospective study, color Doppler flow imaging was used for the estimation of the C/U ratio in fetuses that were small for their gestational age, in 70 singleton pregnancies between 29 and 42 weeks of gestation. The subjects were categorized into two groups, with Group A consisting of 35 small for gestational age (SGA) fetuses with a normal C/U ratio (1.05 or higher), and Group B comprising 35 SGA fetuses with an abnormal C/U ratio (below 1.05). RESULT: The mean C/U ratio values for birth weight and gestational age were higher in group A than in group B. Fetuses born to mothers in group B stayed longer in the neonatal special care unit (NSCU), whereas the period from ultrasound examination to delivery was higher in the cases in group A. A higher percentage of mothers with an abnormal C/U ratio underwent cesarean section. Fetuses with an absent end-diastolic velocity of the umbilical artery had a higher morbidity. Three stillbirths occurred in fetuses with an absent end-diastolic velocity of the umbilical artery. CONCLUSION: Our results suggest that the C/U ratio is a good predictor of neonatal outcome, and could be used to identify fetuses at risk of morbidity and mortality. Fetal umbilical artery AEDV with intrauterine growth restriction is associated with high perinatal morbidity and mortality.

Adult↗

Cytogenetics of the Anopheles gambiae complex in Sudan, with special reference to An. arabiensis: relationships with East and West African populations.

The species composition of malaria vector mosquitoes belonging to the Anopheles gambiae complex (Diptera: Culicidae) from >40 localities in Sudan, representing most ecological situations, was determined by analysis of ovarian polytene chromosomes. Of 2162 females, 93% were identified as An. arabiensis Patton and 7% were An. gambiae Giles sensu stricto. No hybrids were found between the two species. Anopheles arabiensis occurred in all but two sites, whereas An. gambiae s.s. was effectively limited to the southernmost, more humid localities. For chromosomal paracentric inversions, the degree of polymorphism was low in An. gambiae s.s. (inversions 2La, 2Rb and 2Rd), higher in An. arabiensis (inversions Xe, 2Ra, b, bc, d1, s; 3Ra, d). Anopheles gambiae samples from Sudan were all apparently panmictic, i.e. they did not show restricted gene flow such as observed among West African populations (interpreted as incipient speciation). Chromosomal inversion patterns of An. gambiae in southern Sudan showed characteristics of intergrading Savanna/Forest populations similar to those observed in comparable eco-climatic situations of West Africa. Anopheles arabiensis was polymorphic for inversion systems recorded in West Africa (2Ra, 2Rb, 2Rdl, 3Ra) and for a novel 2Rs polymorphism, overlapping with inversion systems 2Rb and 2Rd1. Samples carrying the 2Rs inversion were mostly from Khashm-el-Girba area in central-eastern Sudan. In the great majority of the samples all polymorphic inversions were found to be in Hardy-Weinberg equilibrium. Sudan populations of An. arabiensis should therefore be considered as generally panmictic. Anopheles arabiensis shows more inversion polymorphism in west than in east African populations. Sudan populations have more evident similarities with those from westwards than those from eastwards of the Great Rift Valley. The possible influence of the Rift on evolution of An. arabiensis is discussed.

Africa, Eastern↗

Nutritive value of traditional sweets consumed in the Arab Gulf countries.

Proximate, mineral, fatty acid and cholesterol composition of eight traditional sweets commonly consumed in the Arab Gulf countries were determined. Four sweets were obtained from Bahrain, whereas the other sweets were obtained from Oman. Protein level ranged from 0.2 to 9.0%, while the fat content ranged from 7.9 to 18.0%. In general, the sweets were found to be high in energy content but poor in most minerals. Iron and zinc contents were low (less than 2 and less than 1 mg/100 g for iron and zinc, respectively). Cholesterol was high in four sweets (range from 10.6 to 20.4 mg/100 g), mainly because of the use of animal fat in preparation of these sweets. The fatty acids profiles showed that palmitic and oleic acids were predominant. One sweet (eggbaith) was found to be very high in linoleic (42%) and low in palmitic (9.6%) acids. The study showed that some traditional sweets are nutritious, while others should be consumed with moderation.

Adolescent↗

The prevalence of antibody to human parvovirus B19 in pregnant women in Kuwait.

Infection with parvovirus B19 during pregnancy is known to be associated with various fetal damage, such as aplastic anemia and hydrops fetalis. Our objective was to study the seroprevalence of parvovirus B19 in the obstetric population in Kuwait and to compare this with that in the adult population in other regions. Blood samples from 1047 pregnant women were used in this prospective study. Information regarding patient's age, parity, nationality and symptoms was obtained at the time of collection of the sample. Blood was tested for IgG and IgM antibodies specific for parvovirus B19 using the ELISA technique. The overall prevalence for IgG and IgM was 53.3 and 2.2%, respectively. IgG seropositivity was higher in non-Kuwaiti women, while IgM antibodies was more frequent in Kuwaiti women. A total of 17.4% of the acutely infected patients were symptomatic. Prevalence of parvovirus B19 infection in Kuwait is comparable with that in the other countries.

Adult↗

Pattern of parvovirus B 19 infection during different trimesters of pregnancy in Kuwait.

OBJECTIVE: Aims of this study were to determine the IgG and IgM seropositivity to parvovirus B19 during the three trimesters of pregnancy. METHODS: Initially, a total of 1,047 pregnant women were included in a prospective study. Blood samples were obtained from 343, 406 and 298 cases in the first, second and third trimesters, respectively. To study the incidence of seroconversion, a second sample of blood was obtained 2-4 weeks later from the first 100 cases, who were IgG and IgM negative in the first trimester. RESULTS: The seroprevalence of parvovirus B19 IgG and IgM was 53.3% and 2.2%, respectively. The incidence of seroconversion was 16.5%. The rate of fetal loss was 15.4% in patients with acute infection, all of which occurred in the first two trimesters. CONCLUSIONS: The percentage of IgG positive cases is significantly higher in first and second trimesters compared to the third trimester. The seroconversion rate was 16.5%.

Abortion, Spontaneous↗

Potentiometric sensors for the selective determination of sulbutiamine.

Five novel polyvinyl chloride (PVC) matrix membrane sensors for the selective determination of sulbutiamine (SBA) cation are described. These sensors are based on molybdate, tetraphenylborate, reineckate, phosphotun gestate and phosphomolybdate, as possible ion-pairing agents. These sensors display rapid near-Nernstian stable response over a relatively wide concentration range 1x10(-2)-1x10(-6) M of sulbutiamine, with calibration slopes 28 32.6 mV decade(-1) over a reasonable pH range 2-6. The proposed sensors proved to have a good selectivity for SBA over some inorganic and organic cations. The five potentiometric sensors were applied successfully in the determination of SBA in a pharmaceutical preparation (arcalion-200) using both direct potentiometry and potentiometric titration. Direct potentiometric determination of microgram quantities of SBA gave average recoveries of 99.4 and 99.3 with mean standard deviation of 0.7 and 0.3 for pure SBA and arcalion-200 formulation respectively. Potentiometric titration of milligram quantities of SBA gave average recoveries of 99.3 and 98.7% with mean standard deviation of 0.7 and 1.2 for pure SBA and arcalion-200 formulation, respectively.

Biosensing Techniques↗

Influence of seasonal variation on pregnancy-induced hypertension and/or preeclampsia.

Seasonal variation of temperature and humidity are said to influence the incidence of hypertensive disorders of pregnancy. The aim of this study was to determine if temperature and humidity exert any influence on the incidence of pregnancy-induced hypertension and preeclampsia in Kuwait. This is a retrospective study performed in the Maternity Hospital, Kuwait (MHK) in the years 1992-1994. Monthly distribution of all deliveries and those in which the patients had pregnancy-induced hypertension and preeclampsia were recorded. There are some studies including ours which do not show any significant correlation between meteorological factors and hypertensive disorders of pregnancy. We found that the incidence of pregnancy-induced hypertension per 1,000 deliveries was high in June when the temperature was very high and the humidity at its lowest. The reverse was true for the incidence of preeclampsia per 1,000 deliveries, which was high in November when the temperature was low and the humidity high.

Female↗

Familial hemiplegic migraine in the west of Scotland: a clinical and genetic study of seven families.

OBJECTIVES: Clinical and genetic characterisation of families in the west of Scotland with familial hemiplegic migraine. METHODS: Families with familial hemiplegic migraine were identified via probands attending the regional paediatric neurology and child development centre. All available family members were assessed clinically and genetic linkage studies for the known familial hemiplegic migraine gene locus on chromosome 19 were carried out on three families. RESULTS: Seven unrelated kindreds with familial hemiplegic migraine were identified. Clinical information was obtained on 138 family members, 27 of whom fulfilled the International Headache Society criteria for familial hemiplegic migraine. Whereas the severity, duration, frequency, and temporal progression of acute hemiplegic migrainous attacks showed pronounced variability within and between families, and even in the same individual over time, no true clinical heterogeneity of the condition was apparent. Genetic linkage analysis gave results consistent with linkage to the familial hemiplegic migraine gene locus on chromosome 19p in one family. In the other two families, evidence against linkage was obtained. There was no significant clinical difference between these three families. CONCLUSIONS: This study provides characterisation of the clinical features of familial hemiplegic migraine in a British population. Significant variability was found in the frequency and character of migraine attacks within and between families, and no true clinical heterogeneity was identified. On the other hand, further evidence for genetic heterogeneity of the condition was found.

Adolescent↗