Beneficial effects of n-hexane bark extract of Onosma echioides L. on diabetic peripheral neuropathy

Onosma echioides Linn (Boraginaceae) is the most frequently used curative herb widely used for kidney obstruction, sciatic pain, and gout. The present study was designed to investigate the therapeutic effects of n-hexane bark extract of O. echioides (OE) L. root in vivo against Streptozotocin-induced diabetic neuropathy in SD rats. For in vivo activity, the experiment was categorized into five different groups (n = 5). Group-I was considered as nondiabetic/normal control (NC) treated with 0.5% carboxymethyl cellulose (CMC), Group II as diabetic control, Group-III, IV, and V served as diabetic treated with OE 50, OE 100, and pregabalin at a dose of 50, 100, and 10 mg/kg body weight, orally, respectively. Body weight, blood glucose, oral glucose tolerance test, behavioral studies (motor coordination test, thermal hyperalgesia, cold allodynia, locomotor activity, oxidative biomarkers (thio barbituric acid reactive substances [TBARS], superoxide dismutase [SOD], glutathione [GSH], and catalase), and histopathology of the sciatic nerve were performed. Treatment with OE showed a dose-dependent increase in neuroprotective activity by improving the myelination and decreasing the axonal swelling of nerve fibers. The verdicts of behavioral activities showed a remarkable effect on animals after the treatment of extract and standard drug pregabalin. In conclusion, our findings supported the traditional application of OE and explored its importance in the management of diabetic neuropathy. Additional clinical experiments may provide novel therapeutic drugs for diabetes and its complications.     

Interaction between zinc and calcium in skeletal muscle in young growing rats

The purpose of the present study was to determine whether zinc and calcium could interact at the tissue level. In the first part of the study, adult rats were injected with ZnCl₂ dissolved in a physiological saline solution to determine the effects of Zn on Ca levels in various tissues. In the second part of the study, weaned rats (at day 22 postnatally) were fed a diet supplemented with Zn until day 50 and were then sacrificed. In both instances, blood, brain, heart, liver, and skeletal muscle were taken and analyzed. In the Zn-injected group, the brain, heart, and liver showed no interaction between Zn and Ca. The skeletal muscle, in contrast, showed a decrease in Ca in the homogenate, whereas Zn contents showed a significant increase at the sarcoplasmic reticulum (SR). Likewise, in the Zn-supplemented group, the Zn content of the SR vesicle of the skeletal muscle showed an increase, whereas Ca content of the pellet (14,000 g), which contains cell debris, nucleus, mitochondria, and SR vesicles of this group, showed a decrease. Current findings suggest antagonistic effects between Zn and Ca on this tissue. Zn may play a critical role in cellular function through the alteration of itnracellular distribution of Ca in skeletal muscle.     

绿脓杆菌群集生长效应

本文通过群集的绿脓杆菌在高盐、酸性培养基上生长试验,抗金黄色葡萄球菌的拮抗试验及冷休克试验,证明了绿脓杆菌群集生长效应。主要表现为群集的绿脓杆菌可以在含10～20%NaCl 的培养基上生长;pH4环境中也可生长。同样条件下,对照几乎均为阴性。分散成单个细胞分布的绿脓杆菌对冷反应敏感,群集则有抗冷休克作用。实验条件下,密集的金黄色葡萄球菌生长对分散的绿脓杆菌有拮抗作用,群集则可抵抗这种作用而生长。讨论中初步分析了群集生长效应的机理和对细菌种群在自然生境中的稳定作用。     

Intrinsically Unstructured Sequences in the mRNA 3ʹ UTR Reduce the Ability of Poly(A) Tail to Enhance Translation

The 5? cap and 3? poly(A) tail of mRNA are known to synergistically stimulate translation initiation via the formation of the cap?eIF4E?eIF4G?PABP?poly(A) complex. Most mRNA sequences have an intrinsic propensity to fold into extensive intramolecular secondary structures that result in short end-to-end distances. The inherent compactness of mRNAs might stabilize the cap?eIF4E?eIF4G?PABP?poly(A) complex and enhance cap-poly(A) translational synergy. Here, we test this hypothesis by introducing intrinsically unstructured sequences into the 5? or 3? UTRs of model mRNAs. We found that the introduction of unstructured sequences into the 3? UTR, but not the 5? UTR, decreases mRNA translation in cell-free wheat germ and yeast extracts without affecting mRNA stability. The observed reduction in protein synthesis results from the diminished ability of the poly(A) tail to stimulate translation. These results suggest that base pair formation by the 3? UTR enhances the cap-poly(A) synergy in translation initiation.     

Algae-herbivore interactions with Allee effect and chemical defense

Macroalgae exhibit a variety of characteristics that provide a degree of protection from herbivores. One characteristic is the production of chemicals that are toxic to herbivores. The toxic effect of macroalgae on herbivorous reef fish is studied by means of a spatiotemporal model of population dynamics with a nonmonotonic toxin-determined functional response of herbivores. It is assumed that the growth rate of macroalgae is mediated by Allee effect. We see that under certain conditions the system is uniformly persistent. Conditions for local stability of the system is obtained with weak and strong Allee effects. We observe that in presence of Allee effect on macroalgae, the system exhibits complex dynamics including Hopf bifurcation and saddle-node bifurcation. The obtained results show that the spatiotemporal system does not exhibit diffusion-driven instability. Computer simulations have been carried out to illustrate different analytical results.     

A genetic and spatial Bayesian analysis of mastitis resistance

A nationwide health card recording system for dairy cattle was introduced in Norway in 1975 (the Norwegian Cattle Health Services). The data base holds information on mastitis occurrences on an individual cow basis. A reduction in mastitis frequency across the population is desired, and for this purpose risk factors are investigated. In this paper a Bayesian proportional hazards model is used for modelling the time to first veterinary treatment of clinical mastitis, including both genetic and environmental covariates. Sire effects were modelled as shared random components, and veterinary district was included as an environmental effect with prior spatial smoothing. A non-informative smoothing prior was assumed for the baseline hazard, and Markov chain Monte Carlo methods (MCMC) were used for inference. We propose a new measure of quality for sires, in terms of their posterior probability of being among the, say 10% best sires. The probability is an easily interpretable measure that can be directly used to rank sires. Estimating these complex probabilities is straightforward in an MCMC setting. The results indicate considerable differences between sires with regards to their daughters disease resistance. A regional effect was also discovered with the lowest risk of disease in the south-eastern parts of Norway.     

Biosensors for process monitoring

Summary A short review about the biosensor research activities for bioprocess monitoring in the F.R.G. after its reunification is given. The principles of biosensor applications are presented. In situ sensors and sensors based on the principles of flow injection analysis are studied. Some applications of a four-channel enzyme thermistor, bio-field effect transistors, and immunoanalysis systems for real process monitoring are presented.     

Effect of visible light on carotenogenesis in arthroconidiating Trichophyton mentagrophytes

The effect of visible light on carotenoid content in the dermatophyte Trichophyton mentagrophytes ATCC 26323 was investigated. The fungus T. mentagrophytes accumulated several carotenoids when arthroconidiated on Sabouraud glucose agar at 37°C. When this fungus was irradiated with moderate fluence rates of white light, the resultant arthroconidia contained considerably less carotenoids in comparison with dark controls although growth and arthroconidiation of this fungus were not at all affected by visible light. The reduction of carotenoid content in arthroconidia was due primarily to blue light, although red light caused a slight decrease in pigmentation. The suppressive effect of visible light on pigmentation was fluence rate dependent. Carotenoid accumulation in arthroconidia was inversely and exponentially related to the fluence rate of light. Carotenoid formation in arthroconidiating T. mentagrophytes was neither photoinducible nor photostimulative. An analysis of isolated carotenoids revealed that visible light caused a quantitative reduction in pigmentation, and no single carotenoid was selectively decreased.Non-standard abbreviations PI pigmentation index - r coefficient of correlation     

Characterization of permissivity for hobo -mediated gonadal dysgenesis in Drosophila melanogaster

The hobo transposon is responsible for one of the three hybrid dysgenic systems that have been described in Drosophila melanogaster. Most studies on the hobo dysgenic system have been carried out using the PM system as a reference. However, these two systems differ significantly. In particular, several studies have failed to find any correlation between the molecular structures of hobo elements, the instability of the transposon and the incidence of gonadal dysgenic (GD) sterility. On the other hand, no study of the ability of females to permit hobo activity in their progeny when they are crossed with males harboring active hobo elements (permissivity) has yet been reported. In order to investigate the parameters involved in hobo permissivity, four E strains were studied with regard to the molecular nature of their hobo sequences and the GD sterility induced by a controlled source of hobo transposase. We show that hobo permissivity varies both within and between E strains. Moreover, permissivity decreases with age in E females. Our results are discussed with respect to similar phenomena that have been described in relation to the reactivity of the IR dysgenic system. Received: 17 August 1998 / Accepted: 17 December 1998