Interaction between cytotoxic effects of γ-radiation and folate deficiency in relation to choline reserves

The search for non-toxic radio-protective drugs has yielded many potential agents but most of these compounds have certain amount of toxicity. Recent studies have indicated that bio-molecules such as folate and choline might be of radio-protective value as they are, within broad dose ranges, non-toxic to humans and experimental animals. The objective of the present study was to investigate choline dependent adaptive response to potential synergistic cytotoxic effect of folate deficiency and γ-radiation. Male Swiss mice maintained on folate sufficient diet (FSD) and folate free diet (FFD) based on AIN-93 M formula, were subjected to 1–4 Gy total body γ-irradiation. To investigate liver DNA damage, apurinic/apyrimidinic sites (AP sites) were quantified. A significant increase in liver DNA AP sites with concomitant depletion of liver choline reserves was observed when γ-radiation was combined with folate deficiency. Further work in this direction suggested that cytotoxic interaction between folate deficiency and gamma radiation might induce utilization of choline and choline containing moieties by modifying levels of key regulatory enzymes dihydrofolate reductase (DHFR) and choline oxidase (ChoOx). Another major finding of these studies is that significant liver damage at higher doses of radiation (3–4 Gy), might release considerable amounts of choline reserves to serum. In conclusion, a plausible interpretation of the present studies is that folate deprivation and γ-radiation interact to mobilize additional choline reserves of hepatic tissue, for redistribution to other organs, which could not be utilized by folate deficiency alone. Present results clearly indicated a distinct choline pool in liver and kidney tissues that could be utilized by folate deficient animals only under radiation stress conditions.     

种根粗度对丹参出苗及药材产量和质量的影响研究

目的:了解不同粗细根条作种对丹参出苗及药材产量和质量的影响,为丹参规范化栽培技术提供依据.方法:试验采用单因素随机区组设计,齐苗后调查出苗情况和苗子长势,收获时实测小区产量,采用高效液相色谱法测定丹参酮ⅡA和丹酚酸B含量.结果:不同粗细种根对丹参出苗、植株生长、药材产量和质量均有一定影响.结论:中江丹参生产上应采用直径为7～15 mm的根条作种为宜.     

Interaction between cadmium and zinc,copper, or lead in relation to the collagen and mineral content of embryonic chick bone in tissue culture

To investigate the interaction between Cd and Zn, Cu, or Pb in relation to the content of collagen and mineral in bone, femurs obtained from 9-day-old chick embryos were cultivated for 6 days by the Rollertube method. Zn prevented a decrease in collagen content caused by Cd, although Cu and Pb showed no such protective effect. Neither Zn, Cu, nor Pb prevented the decrease in mineral content caused by Cd. In the Cd-treated bone, the Cd content in the presence of Zn was larger than that in the absence of Zn. The Cd content in the cytosol fraction from Cd plus Zn-treated bones was larger than that from Cd-treated ones. When the cytosol fraction was applied to a Sephadex G-75 column, three Cd-containing peaks were observed. The first small peak (HM fraction) was eluted near the void volume, the second large peak (MT fraction) was metallothionein-like protein (MW = about 10,000), and the third peak contained low-molecular-weight (about 2500) compounds. The Cd content in the MT fraction from Cd plus Zn-treated bones was larger than that from Cd-treated ones. From these results it was concluded that a metallothionein-like protein, induced by Zn, served as a Cd scavenger and contributed to the protection against Cd-induced toxicity. On the other hand, when the 100,000g precipitate from cultured bone was solubilized and applied to a Sephadex G-75 column, one peak was observed in the position of the HM fraction. The activity of alkaline phosphatase in the HM fraction from Cd-treated bones was inhibited, but this inhibition was not observed in Cd plus Zn-treated ones. This finding suggests that competition between Cd and Zn in the HM fraction contributes, at least partly, to the protection against Cd-induced toxicity.     

Interaction between cadmium and copper in relation to the collagen metabolism of embryonic chick bone in tissue culture

To investigate the interaction between Cd and Cu in relation to the content of collagen in bone, femurs obtained from 9-day-old chick embryos were cultivated with a combination of Cd and Cu concentrations of 8.9 microM and below for 4 days. When 2.23 or 4.45 microM Cd was added to the medium containing 4.45 or 8.90 microM Cu, the presence of both Cd and Cu caused a remarkable decrease in collagen synthesis compared with a decrease in collagen synthesis caused by either Cd or Cu alone. The results show that Cd and Cu caused an interactive inhibition of collagen synthesis, which was not due to an increase in collagen degradation by Cd and Cu. At concentrations showing inhibition, Cd caused an increase in Cu content and Cu caused an increase in Cd content. The increase in Cd content was mainly caused by the accumulation of Cd in bone mineral. The increase in Cu content was due to binding to metallothionein-like protein in the cytosol induced by Cd. The relationship between inhibition and the increase in both Cd and Cu was not confirmed after division of the bone into diaphysis and epiphysis. The present study showed that Cu aggravated the bone matrix damage caused by Cd.     

产超广谱β-内酰胺酶革兰阴性杆菌的检测和耐药性研究

目的 研究汕头地区革兰阴性杆菌产超广谱β-内酰胺酶(ESBLs)情况及其耐药特性,为临床合理使用抗生素提供依据.方法 收集汕头地区革兰阴性杆菌共1 445株(大肠埃希菌895株和肺炎克雷伯菌550株),采用Vitek-2全自动细菌鉴定和药敏分析仪进行ESBL检测和药敏实验.结果 69.4%大肠埃希菌和33.6%肺炎克雷伯菌产ESBLs.产ESBLs菌株对青霉素类、头孢菌素类和单环类抗生素的耐药率极高;产ESBLs菌株存在多重耐药性,而且对多种抗生素的耐药率明显比不产ESBLs菌株高;产ESBLs菌株和不产ESBLs菌株对亚胺培南均未出现耐药.结论 汕头地区革兰阴性杆菌中ESBLs菌株检出率高;产ESBLs菌株耐药性比不产ESBLs菌株高,且耐药表型多样性;亚胺培南是临床治疗产ESBLs菌株感染的首选药物.     

产超广谱β-内酰胺酶革兰阴性杆菌的检测和耐药性研究

目的 研究汕头地区革兰阴性杆菌产超广谱β-内酰胺酶（ESBLs）情况及其耐药特性,为临床合理使用抗生素提供依据.方法 收集汕头地区革兰阴性杆菌共1 445株（大肠埃希菌895株和肺炎克雷伯菌550株）,采用Vitek-2全自动细菌鉴定和药敏分析仪进行ESBL检测和药敏实验.结果 69.4%大肠埃希菌和33.6%肺炎克雷伯菌产ESBLs.产ESBLs菌株对青霉素类、头孢菌素类和单环类抗生素的耐药率极高 产ESBLs菌株存在多重耐药性,而且对多种抗生素的耐药率明显比不产ESBLs菌株高 产ESBLs菌株和不产ESBLs菌株对亚胺培南均未出现耐药.结论 汕头地区革兰阴性杆菌中ESBLs菌株检出率高 产ESBLs菌株耐药性比不产ESBLs菌株高,且耐药表型多样性 亚胺培南是临床治疗产ESBLs菌株感染的首选药物.     

Interaction of neomycin, tobramycin and amikacin with melanin in vitro in relation to aminoglycosides-induced ototoxicity

The aim of this study was to examine in vitro the interaction between aminoglycoside antibiotics displaying adverse ototoxic effects and melanin which is a constituent of the inner ear. The binding of neomycin, tobramycin and amikacin to model synthetic melanin was studied. It has been demonstrated that all the investigated aminoglycosides form stable complexes with melanin biopolymer. The obtained results show that the amount of drug bound to melanin increases with the increase of initial drug concentration and the incubation time. An analysis of drugs binding to melanin by the use of Scatchard plots has shown that at least two classes of independent binding sites must be implicated in the studied aminoglycoside antibiotic-melanin complexes formation: strong binding sites (n1) with the association constant K1 approximately 0.2-2.0 x 10(5) M(-1) and weak binding sites (n2) with K2 approximately 1.0-4.9 x 10(3) M(-1). Based on the values of association constants the following order of drugs affinity to DOPA-melanin was found: tobramycin > amikacin > neomycin. The ability of the analyzed aminoglycoside antibiotics to form complexes with melanin in vitro may be one of the reasons for their ototoxicity in vivo, as a result of their accumulation in melanin in the inner ear.     

Chemotaxonomic variability in Zizyphus mouritiana varieties and its pharmacological properties in relation to human health

Twenty varieties of ber (Zizyphus mouritiana), namely umaran, katha, bilayati, kaithli, ZG-3, gola, safeda rohtak, takadi, tikari, banarasi karaka, seo, sonaur-2, sonaur-3, ilaichi, mundia murahra, pathan, kakrola gola, seb, golden yellow and chhuhara, were investigated for the presence of phenolic acids in stem bark, leaves and fruits using high performance liquid chromatograph. Results indicated the presence of tannic (retention time (Rt.) 2.76 min), gallic (Rt. 2.86 min), caffeic (Rt. 3.12 min), vanillic (Rt. 3.26 min), ferulic (Rt. 3.42 min), chlorogenic (Rt. 4.16 min) and cinnamic acids (Rt. 4.45 min) in varying amounts in different parts in of these varieties. In fruits of seven varieties, namely, kaithly, sonaur-2, sonaur-3, mundia murahra, pathan, golden yellow and chhuhara, oxalic acid (Rt. 3.00 min) was also detected. Pharmacological properties of phenolic acids of fruits in relation to human health and the possible implications of different phenolic acids in chemotaxonomy of different varieties of ber are discussed.     

Interaction of quinidine,disopyramide and metoprolol with melanin in vitro in relation to drug-induced ocular toxicity

The aim of this work was to evaluate binding capacity of quinidine, disopyramide and metoprolol to melanin in vitro. The antiarrhythmics studied cause adverse reactions to the eye. Synthetic DOPA-melanin was used in the studies and a UV spectrophotometric method was employed to determine the drugs. The studies of the kinetics of the formation of quinidine-melanin, disopyramide-melanin and metoprolol-melanin complexes indicate that for all the complexes investigated the maximum time to reach reaction equilibrium is 24 h. Binding parameters, i.e., the numbers of independent binding sites and the association constants were determined on the basis of the Scatchard plots. An analysis of the binding curves obtained supports our conclusion that both strong (n1) and weak (n2) binding sites are involved in the formation of the complexes investigated. The total numbers of binding sites in synthetic DOPA-melanin complexes with quinidine, disopyramide and metoprolol were 0.525, 0.493 and 0.387 micromol/mg, respectively. The quinidine-melanin complex is characterized by greater stability (K1 = 3.00 x 10(5) M(-1), K2 = 1.75 x 10(3) M(-1)) in comparison with biopolymer complexes with disopyramide (K1 = 1.12 x 10(4) M(-1), K2 = 6.04 x 10(2) M(-1)) and metoprolol (K1 = 1.42 x 10(4) M(-1), K2 = 7.89 x 10(2) M(-1)). The ability of these drugs to form complexes with melanin in vitro may be one of the reasons for their ocular toxicity in vivo, as a result of their accumulation in melanin in the eye.     

The content of parthenolide and its yield per plant during the growth of Tanacetum parthenium

During the growth of Tanaceum parthenium (L.) Schultz-Bip. Feverfew, Asteraceae) the percentage of parthenolide was the highest at an early stage (just before the formation of stems). The yield of parthenolide per individual plant gradually increased from about 10 mg at the beginning of the study to about 20 mg when the plant was in full bloom. Parthenolide was present in the leaves and flowerheads, but not in the stems. Drying at ambient temperature and lyophilisation had no negative influence on the yield of parthenolide per individual plant on comparing the results with those of fresh plant material. Based on the results of this study and on data from the literature we propose to distinguish two qualities of feverfew: a: Tanaceti parthenii folium (feverfew leaf), harvested at an early stage before the formation of the stems and b: Tanaceti parthenii herba (feverfew herb), harvested at full bloom, with a minimum parthenolide content of 0.50% and 0.20%, respectively, calculated on a dry weight basis. Both drugs can be easily distinguished by means of microscopic examination.     

Interaction of cadmium,zinc and copper in relation to smoking habit,age and histopathological findings in human kidney cortex

In this study the concentrations of cadmium, zinc and copper were determined by atomic absorption spectrophotometry in 51 post mortem kidney cortex samples. A histopathological examination of the kidney was also performed. These parameters, together with age and smoking habit, were statistically related by means of factor analysis. The results show that the first factor associated smoking habit, cadmium and zinc and the second factor histopathological findings and age.     

Papaver bracteatum Lindley: thebaine content in relation to plant development

Four thebaine-rich varieties of P. bracteatum have been grown in the open over two seasons and the thebaine distribution in aerial parts examined to determine the most suitable source material for commercial production. The leaves contained only 0·1 to 0·15%; the capsules 0·5 to 3·0% and the bled latex 28 to 53%. The maximum for the latter occurred about 3–4 weeks after petal opening and during the day, at about 15.00 h. A product ‘bractium’ prepared exactly as opium from P. somniferum contained up to 55% thebaine and calculations from the 1974 results gave theoretical yields up to 58 kg of thebaine per hectare. However this is a very labour intensive method; furthermore bled latex only represents about 46% of the total thebaine of the capsule. In addition the pedicels contain significant amounts of thebaine, so that fruiting tops may be recommended as source material. In the capsule the thebaine content reaches a peak 3 to 4 weeks after petal opening and again two weeks later. At this fully ripe stage there is a theoretical yield of 50 kg per hectare. Two further advantages accrue from collection at this time: the ripe seeds can probably be used for similar purposes as poppy seed; and the pericarps at this stage contain no ‘bound thebaine’ (i.e., thebaine insoluble in MeOH:NH₄OH but soluble in acetic acid—in unripe capsules bound thebaine represents 18 to 36% of the total thebaine). There is some evidence that, as this perennial plant increases in age, the capacity for thebaine production seems to continue increasing. Storage of raw material, even in ideal conditions, led to a loss of thebaine of 12 to 20% in one year.     

Differential growth of the freshwater mussel, Lamellidens marginalis in relation to certain drugs

The survival and growth rate of the Indian freshwater mussel, Lamellidens marginalis, (Lamarck) was ascertained in cultivation by using certain drugs in CIFA, fish farm, BBSR (India) during June 1998 to February 1999.Two sets of experiments were carried out to evaluate the effects of drugs like Betamethasone, Calcium, Azathioprine, Stanazolol, and Folic acid. Chloramphenicol was added with each treatment as prophylaxis to prevent the bacterial growth. In the first set, the inactiveness and mortality of the mussels in different drugs were studied through two different dosages and in subsequent tests the fixation of dosage was employed. The study in the second set was regarding the survival, increment of shell length, its thickness, and wet weight in response to different drugs therapy. The drugs were administered parenterally in "fixed dosage" at a regular interval of 21-23 days. The survival rate was good with Betamethasone and Azathioprine that is 75%, whereas it was 16.66% in Folic acid treatment. But the mussels originating from the control site had the significant survival rate though the growth rate was average. Calcium treatment had shown a marked increment of shell thickness and luster. The culture was lasted for 160 days. The wet weight gain of mussels in all the treatments were significant, p<0.0001 whereas increment of shell thickness was significant only in treatment B (Calcium) and treatment D (Azathioprine), p<0.0001 but with regard to the increment of length of mussel, treatment E (Stanazolol) was not significant, p>0.05. The regression analysis was adopted to find out the coefficient of determination (R(2)=0.90, being the best) from the relationship between length and weight of mussels and to establish the LWR equation with condition factor k=W/L(b).     

Serotyping clinical isolates of Pseudomonas aeruginosa in relation to infection site antibiotic susceptibility and beta-lactamase production

The present study investigates the association of O-serotype with isolation site, antibiotic resistance, and beta-lactamase production to determine the profiles of Pseudomonas aeruginosa clinical isolates circulating in a Canadian teaching hospital. The most frequently encountered serotypes of Pseudomonas aeruginosa strains isolated from inpatients at H?tel-Dieu de Montréal hospital during the period 1992-1993 were O1, O3, O5, O6, O10, and O11 (9-13%) isolated from pus, urine, sputa and other sources. Serotype O1 was the most sensitive in contrast to serotype O3 which was resistant to virtually all antibiotics tested except to imipenem and quinolone. Of the strains of Pseudomonas aeruginosa, more than 50% with the most encountered serotype produced a high level of beta-lactamase.