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991.
Wael Ammar Aldaddou Abdullah S. M. Aljohani Idris Adewale Ahmed Naser A. Al-Wabel Ibrahim M. El-Ashmawy 《化学与生物多样性》2023,20(7):e202300115
Most heavy metals and industrial chemicals such as nicotine and lead cause harm to the reproduction process through a decrease in sperm motility, fertilization process, and sperm binding to the oocyte. Salvia officinalis L. (sage) has been reported to enhance serum testosterone levels and other certain biochemical enzymes. Thus, the current study is aimed at evaluating the potential health benefits of S. officinalis L. methanol extract on lead and nicotine hydrogen tartrate-induced sperm quality degeneration in male rats and also identifying some of the non-polar volatile bioactive compounds that might be attributed to the bioactivity of S. officinalis extract using gas chromatography-mass spectrometry (GC/MS). In the study, fifty-four mature male albino rats of about 220–250 g [were divided randomly and equally into 9 groups (n=6)]. Sperm quality degeneration was induced through the oral administration of 1.5 g/L of lead acetate in drinking water or peritoneal injection of 0.50 mg/kg (animal weight) nicotine hydrogen tartrate for sixty days. Two doses (200 & 400 mg/kg b.w.) of S. officinalis L. were used. The rats were anesthetized after the experimental period and then sacrificed. Blood samples were collected while the epididymis, testicle, and accessory sex organs (prostates and seminal vesical) were taken for histopathological studies. Twelve major compounds were identified through the GC/MS analysis of S. officinalis L. methanol extract. Lead and nicotine toxicity had a great effect on the rats’ sperm quality causing a significant (p<0.05) decrease in the quantity of sperm and sperm motility as well as an upsurge in the abnormalities of the sperm and a reduction in the length & diameter of seminiferous tubules and size & weight of sexual organs (accessory sex glands, epididymis, and testis). The administration of S. officinalis L. methanol extract, however, had a positive impact on the sexual organ weights, semen quality & quantity, and rats’ fertility, thus, ameliorating the adversative effects of both lead and nicotine. Further evaluation and isolation of the bioactive components are recommended as potential drug leads. 相似文献
992.
William M. U. Daniels Abdullah Jaffer Vivienne A. Russell Joshua J. F. Taljaard 《Neurochemical research》1994,19(12):1539-1543
Bipolar electrodes were implanted into the CA1 pyramidal cells of the dorsal hippocampus and the effect of electrical stimulation of these cells on corticosterone secretion was investigated in freely moving rats. Histology showed that the electrodes were positioned in close proximity to the CA1 pyramidal cells. Rats that were subjected to high intensity electrical stimulation (1, 10, and 100A) behaved differently when compared to their sham stimulated controls. They were more active and displayed wet dog shakes. Plasma corticosterone levels increased dose-dependently in rats subjected to different electrical stimulation intensities. Although prior treatment (24 hours) of rats with DSP4 (60 mg/kg, i.p.) significantly reduced hippocampal noradrenaline content by 46%, it did not bring about any behavioural changes. DSP4 treatment also had no effect on electrically stimulated corticosterone release. These data suggested that stimulation of CA1 pyramidal cells may lead to increased corticosterone release and that a decrease in hippocampal noradrenaline concentration was unable to alter this corticosterone response. 相似文献
993.
Abdullah M.A. Ali A.M. Marziah M. Lajis N.H. Ariff A.B. 《Plant Cell, Tissue and Organ Culture》1998,54(3):173-182
Morinda elliptica (Rubiaceae) cell suspension cultures were established in shake flask system for the production of anthraquinones.
The optimized medium formulation for cell growth and anthraquinone production is proposed. Murashige and Skoog's basal medium
(MS) was found to be the best medium, used in combination with 0.5 mg l-1 NAA and 0.5 mg l-1 kinetin. At the range of sucrose
concentration tested (3–8% w/v), 8% was the best in enhancing both cell growth and anthraquinone production. A strategy to
formulate growth and production medium by manipulating culture age and inoculum age, the type of medium formulation used to
grow inoculum, incubation temperature and light intensity was established. By using 18 month old culture and 7 day old inoculum
at incubation temperature of 27 ± 3 °C, anthraquinone yield of 2.9 g l-1 and 4.5 g l-1, under illumination of 1200 lux and
in the dark was obtained, respectively.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
994.
995.
Ca2+ and protein kinase C activation of mucin granule exocytosis in permeabilized SPOC1 cells 总被引:2,自引:0,他引:2
Scott C. E.; Abdullah Lubna H.; Davis C. William 《American journal of physiology. Cell physiology》1998,275(1):C285
Mucin secretion by airway goblet cells is under the control ofapical P2Y2, phospholipaseC-coupled purinergic receptors. In SPOC1 cells, the mobilization ofintracellular Ca2+ by ionomycin orthe activation of protein kinase C (PKC) by phorbol 12-myristate13-acetate (PMA) stimulates mucin secretion in a fully additive fashion[L. H. Abdullah, J. D. Conway, J. A. Cohn, and C. W. Davis.Am. J. Physiol. 273 (Lung Cell. Mol. Physiol. 17):L201-L210, 1997]. This apparent independence between PKC andCa2+ in the stimulation of mucinsecretion was tested in streptolysin O-permeabilized SPOC1 cells. Thesecells were fully competent to secrete mucin whenCa2+ was elevated from 100 nM to3.1 µM for 2 min following permeabilization; theCa2+EC50 was 2.29 ± 0.07 µM.Permeabilized SPOC1 cells were exposed to PMA or 4-phorbol atCa2+ activities ranging from 10 nMto 10 µM. PMA, but not 4-phorbol, increased mucin release at allCa2+ activities tested: at 10 nMCa2+ mucin release was 2.1-foldgreater than control and at 4.7 µM Ca2+ mucin release was maximal(3.6-fold increase). PMA stimulated 27% more mucin release at 4.7 µMthan at 10 nM Ca2+. Hence, SPOC1cells possess Ca2+-insensitive,PKC-dependent, and Ca2+-dependentPKC-potentiated pathways for mucin granule exocytosis. 相似文献
996.
L.Z. JIN Y.W. Ho N. Abdullah M.A. Ali S. Jalaludin 《Letters in applied microbiology》1996,23(2):67-71
L.Z. JIN, Y.W. HO, N. ABDULLAH, M.A. ALI AND S. JALALUDIN. 1996. Twelve Lactobacillus strains isolated from chicken intestine, which demonstrated a strong and moderate capacity to adhere to the ileal epithelial cells in vitro , were used to investigate their inhibitory ability against five strains of salmonella, i.e. Salmonella enteritidis 935/79, Salm. pullorum, Salm. typhimurium, Salm. blockley and Salm. enteritidis 94/448, and three serotypes of Escherichia coli , viz. E. coli O1 : K1, O2 : K1 and O78 : K80. The results showed that all the 12 Lactobacillus isolates were able to inhibit the growth of the five strains of salmonella, and the three strains of E. coli in varying degrees. Generally, they were more effective in inhibiting the growth of salmonella than E. coli . Inhibition of the pathogenic bacteria was probably due to the production of organic acids by the Lactobacillus isolates. 相似文献
997.
L.Z. Jin Y.W. Ho M.A. Ali N. Abdullah K.B. Ong S. Jalaludin 《Letters in applied microbiology》1996,22(3):229-232
L.Z. JIN, Y.W. HO, M.A. ALI, N. ABDULLAH, K.B. ONG AND S. JALALUDIN. 1996. A total of 46 Lactobacillus isolates obtained from chicken intestine were assessed on their ability to adhere to the chicken ileal epithelial cell (IEC) in vitro . Twelve out of the 46 isolates showed moderate to good ability to adhere to the IEC. Temperature (between 4°C and 42°C) did not affect attachment. Incubation (contact) time of 30 min was found to be insufficient for the attachment of bacteria to the IEC, but contact time beyond 1 h did not increase this ability. The pH values (4–7) of the suspending buffer did not have any significant effect on the attachment of bacteria to the IEC, but at pH 8 it was reduced significantly (P < 0.05). 相似文献
998.
Abdullah Kutlar Ferdane Kutlar Li-Ghao Gu Sylvia M. Mayson Titus H. J. Huisman 《Human genetics》1990,85(1):106-110
Summary A recently developed high performance liquid chromatographic (HPLC) procedure using a weak cation exchanger (PolyCAT) in columns of different sizes was used to quantify fetal hemoglobin (Hb F) in blood of normal adults and -thalassemia (-thal) heterozygotes with ten different types of mutations. Preparative PolyCATHPLC greatly facilitated the characterization of isolated Hb F, i.e., the determination of the relative quantities of the G and A chains. The method is accurate and allows quantitation of Hb F at the 0.5% level; preparative PolyCAT-HPLC allows isolation of (nearly) pure Hb F from blood samples with low (< 1%) Hb F. Adult Hb F levels were determined in 69 normal adults (including 24 diabetics); Hb F levels fell below 1% except for subjects with abnormal -G-G arrangement and a CT mutation at position -158 relative to the Cap site of both G genes. The effect of the same mutation in the normal-G-A-arrangement was variable. Certain -thal mutations (namely, those at positions -29;-88; IVS-I-1; IVS-II-1) were associated with high Hb F levels in heterozygotes, while those at nucleotide (nt) positions IVS-I-6; IVS-I-110; codon 24; codon 39; codons 41/42; IVS-II-745 were not. G values varied and often fell into two groups (high G and low G); high G values were not associated with high Hb F values. The chromatographic procedure is ideally suited for Hb A2 quantitation. Average values of Hb A2 in -thal heterozygotes with any one of nine of the ten mutations were twice that of normals; the one exception was the -thal heterozygote with the IVS-I-6 (TC) mutation with an average low Hb A2 value of 3.6%. 相似文献
999.
Abdullah Jaffer Anita Searson Vivienne Ann Russell Joshua Joachim Fransua Taljaard 《Neurochemical research》1990,15(1):13-16
The effect of DSP4 [N-(2-chloroethyl)-N-ethyl-2 bromobenzylamine], a neurotoxin which selectively lesions noradrenergic projections from the locus coeruleus, on thyrotropin (TSH) secretion was investigated in the rat. DSP4 treatment (60 mg/kg injected i.p. 10 days prior to experimentation) significantly decreased the noradrenaline (NA) content of the hippocampus, frontal cortex and hypothalamus of the rat brain. DSP4 treatment did not affect the clonidine (250 g/kg, i.p.) or TSH-releasing-hormone (TRH 5 g/kg i.v.) induced stimulation or the isoproterenol induced inhibition of TSH secretion in the rat. These results suggest that the noradrenergic projection from the locus coeruleus to the hypothalamus does not play a significant role in the regulation of TSH secretion. Furthermore, the noradrenergic deficiency did not give rise to the development of the abnormal TSH response to TRH administration which is frequently observed in depression. 相似文献
1000.
B Collett A Alhaq N B Abdullah L Korjtsas R J Ware N J Dodd E Alimo J Ponte D Vergani 《BMJ (Clinical research ed.)》1984,289(6454):1251-1254
Complement activation was assessed in 34 patients undergoing cardiopulmonary bypass. Arterial concentrations of complement fragments Ba and C3d rose in all patients, the increase in Ba preceding that of C3d. At the same time as complement fragments were being generated the arterial neutrophil count fell. These findings suggest (a) that complement activation is initiated by the alternative pathway during cardiopulmonary bypass and (b) that complement activation mediates loss of neutrophils during bypass. Complement mediated loss of neutrophils during the analogous setting of haemodialysis is the result of leucosequestration in the pulmonary vasculature. During cardiopulmonary bypass the lungs are out of circuit, so that activated leucocytes may sequester in other target organs. This may be an aetiological factor in the multi-organ failure occasionally seen after uneventful cardiopulmonary bypass. 相似文献