Immunocytochemical and electron-microscopic investigations of the pineal organ in adult agamid lizards,Uromastix hardwicki

Summary Lacertilian species display a remarkable diversity in the organization of the neural apparatus of their pineal organ (epiphysis cerebri). The occurrence of immunoreactive S-antigen and opsin was investigated in the retina and pineal organ of adult lizards, Uromastix hardwicki. In this species, numerous retinal photoreceptors displayed S-antigen-like immunoreactivity, whereas only very few pinealocytes were labeled. Immunoreactive opsin was found neither in retinal photoreceptors nor in pinealocytes. Electron microscopy showed that all pinealocytes of Uromastix hardwicki resemble modified pineal photoreceptors. A peculiar observation is the existence of a previously undescribed membrane system in the inner segments of these cells. It is evidently derived from the rough endoplasmic reticulum but consists of smooth membranes. The modified pineal photoreceptor cells of Uromastix hardwicki were never seen to establish synaptic contacts with somata or dendrites of intrapineal neurons, which are extremely rare. Vesiclecrowned ribbons are prominent in the basal processes of the receptor cells, facing the basal lamina or establishing receptor-receptor and receptor-interstitial type synaptoid contacts. Dense-core granules (60–250 nm in diameter) speak in favor of a secretory activity of the pinealocytes. Attention is drawn to the existence of receptor-receptor and receptor-interstitial cell contacts indicating intramural cellular relationships that deserve further study.Supported by the Deutsche Forschungsgemeinschaft (Ko 758/31) and the Deutscher Akademischer Austauschdienst (Senior DAAD Research Fellowship to M.A.H.)     

Effect of salinity and inoculation on growth,nitrogen fixation and nutrient uptake ofVigna radiata (L.) Wilczek

This study reports the effect of salinity and inoculation on growth, ion uptake and nitrogen fixation byVigna radiata. A soil EC_e level of 7.5 dS m⁻¹ was quite detrimental causing about 60% decline in dry matter and grain yield of mungbean plants whereas a soil EC_e level of 10.0 dS m⁻¹ was almost toxic. In contrast most of the studied strains of Rhizobium were salt tolerant. Nevertheless, nodulation, nitrogen fixation and total nitrogen concentration in the plant was drastically affected at high salt concentration. A noticeable decline in acetylene reduction activity occurred when salinity level increased to 7.5 dS m⁻¹.     

High-temperature stress in crops: male sterility,yield loss and potential remedy approaches

Global food security is one of the utmost essential challenges in the 21st century in providing enough food for the growing population while coping with the already stressed environment. High temperature (HT) is one of the main factors affecting plant growth, development and reproduction and causes male sterility in plants. In male reproductive tissues, metabolic changes induced by HT involve carbohydrates, lipids, hormones, epigenetics and reactive oxygen species, leading to male sterility and ultimately reducing yield. Understanding the mechanism and genes involved in these pathways during the HT stress response will provide a new path to improve crops by using molecular breeding and biotechnological approaches. Moreover, this review provides insight into male sterility and integrates this with suggested strategies to enhance crop tolerance under HT stress conditions at the reproductive stage.     

Morphology,physiology and infectivity of twoFrankia isolates An 1 and An 2 from root nodules ofAlnus nitida

Summary Two different strains, An 1 and An 2, were obtained from root nodules ofAlnus nitida Endl., collected from one locality in the area of its natural habitat near Bahrin, District Swat, Pakistan. The light and electron microscopy of the isolates revealed the occurrence of septate and branched hyphae bearing sporangia and vesicles. The strains differed in their growth requirements, nitrogen-fixing ability and production of extracellular pigments, thus indicating the existence of more than oneFrankia strain in the same locality. In the absence of combined nitrogen in the medium strain An 1 formed vesicles and fixed N₂ (up to 200 nmol C₂H₄. mg protein^–1.h^–1), while strain An 2 under the experimental conditions formed only few vesicles and fixed N₂ at a very low rate (ca 10 nmol C₂H₄. mg protein^–1 .h^–1). The nitrogenase activity of strain An 1 was strongly affected by the O₂ concentration.Frankia An 1 and An 2 were infective and effective onA. nitida andA. glutinosa but not onDatisca cannabina andElaeagnus umbellata. Both An 1 and An 2 strains were more infective and effective onA. glutinosa thanFrankia strains AvcIl and CpI1.     

NMR-based metabolomics associated with chronic kidney disease in humans and animals: a one health perspective

Molecular and Cellular Biochemistry - Chronic kidney disease (CKD) is a renal dysfunction that can lead to high rates of mortality and morbidity, particularly when coupled with late diagnosis. CKD...     

Molecular detection and genotyping of Fusarium oxysporum f. sp. psidii isolates from different agro-ecological regions of India

Twenty one isolates of Fusarium oxysporum f. sp. psidii (Fop), causing a vascular wilt in guava (Psidium guajava L.), were collected from different agro-ecological regions of India. The pathogenicity test was performed in guava seedlings, where the Fop isolates were found to be highly pathogenic. All 21 isolates were confirmed as F. oxysporum f. sp. psidii by a newly developed, species-specific primer against the conserved regions of 28S rDNA and the intergenic spacer region. RAPD and PCR-RFLP were used for genotyping the isolates to determine their genetic relationships. Fifteen RAPD primers were tested, of which five primers produced prominent, polymorphic, and reproducible bands. RAPD yielded an average of 6.5 polymorphic bands per primer, with the amplified DNA fragments ranging from 200–2,000 bp in size. A dendrogram constructed from these data indicated a 22–74% level of homology. In RFLP analysis, two major bands (350 and 220 bp) were commonly present in all isolates of F. oxysporum. These findings provide new insight for rapid, specific, and sensitive disease diagnosis. However, genotyping could be useful in strain-level discrimination of isolates from different agro-ecological regions of India.     

Correction for Irrelevant Absorption in Multicomponent Spectrophotometric Assay of Riboflavin, Formylmethylflavin, and Degradation Products: Kinetic Applications

In the spectrophotometric assay of multicomponent systems involved in drug degradation studies, some minor or unknown degradation products may be present. These products may interfere in the assay and thus invalidate the results due to their absorption in the range of analytical wavelengths. This interference may be eliminated by the application of an appropriate correction procedure to obtain reliable data for kinetic treatment. The present study is based on the application of linear and non-linear irrelevant absorption corrections in the multicomponent spectrophotometric assay of riboflavin and formylmethylflavin during the photolysis and hydrolysis studies. The correction procedures take into account the interference caused by minor or unknown products and have shown considerable improvement in the assay data in terms of the molar balance. The treatment of the corrected data has led to more accurate kinetic results in degradation studies.     

Agonist Leukadherin-1 Increases CD11b/CD18-Dependent Adhesion Via Membrane Tethers

Integrin CD11b/CD18 is a key adhesion receptor that mediates leukocyte migration and immune functions. Leukadherin-1 (LA1) is a small molecule agonist that enhances CD11b/CD18-dependent cell adhesion to its ligand ICAM-1. Here, we used single-molecule force spectroscopy to investigate the biophysical mechanism by which LA1-activated CD11b/CD18 mediates leukocyte adhesion. Between the two distinct populations of CD11b/CD18:ICAM-1 complex that participate in cell adhesion, the cytoskeleton(CSK)-anchored elastic elements and the membrane tethers, we found that LA1 enhanced binding of CD11b/CD18 on K562 cells to ICAM-1 via the formation of long membrane tethers, whereas Mn²⁺ additionally increased ICAM-1 binding via CSK-anchored bonds. LA1 activated wild-type and LFA1^−/− neutrophils also showed longer detachment distances and time from ICAM-1-coated atomic force microscopy tips, but significantly lower detachment force, as compared to the Mn²⁺-activated cells, confirming that LA1 primarily increased membrane-tether bonds to enhance CD11b/CD18:ICAM-1 binding, whereas Mn²⁺ induced additional CSK-anchored bond formation. The results suggest that the two types of agonists differentially activate integrins and couple them to the cellular machinery, providing what we feel are new insights into signal mechanotransduction by such agents.     

A New Miocene-Divergent Lineage of Old World Racer Snake from India

A distinctive early Miocene-divergent lineage of Old world racer snakes is described as a new genus and species based on three specimens collected from the western Indian state of Gujarat. Wallaceophis gen. et. gujaratenesis sp. nov. is a members of a clade of old world racers. The monotypic genus represents a distinct lineage among old world racers is recovered as a sister taxa to Lytorhynchus based on ~3047bp of combined nuclear (cmos) and mitochondrial molecular data (cytb, ND4, 12s, 16s). The snake is distinct morphologically in having a unique dorsal scale reduction formula not reported from any known colubrid snake genus. Uncorrected pairwise sequence divergence for nuclear gene cmos between Wallaceophis gen. et. gujaratenesis sp. nov. other members of the clade containing old world racers and whip snake is 21–36%.