Prophylactic and curative effects of Bacopa monniera in gastric ulcer models.

Bacopa monniera Wettst. (BM, syn. Herpestis monniera L; Scrophulariaceae), is an Ayurvedic drug used as a rasayana. Its fresh juice was earlier reported to have significant antiulcerogenic activity. In continuation, methanolic extract of BM (BME) standardized to bacoside-A content (percentage-38.0 ± 0.9), when given in the dose of 10–50 mg/kg, twice daily for 5 days, showed dose-dependent anti-ulcerogenic on various gastric ulcer models induced by ethanol, aspirin, 2 h cold restraint stress and 4 h pylorus ligation. BME in the dose of 20 mg/kg, given for 10 days, twice daily showed healing effects against 50% acetic acid-induced gastric ulcers. Further work was done to investigate the possible mechanisms of its action by studying its effect on various mucosal offensive acid-pepsin secretion and defensive factors like mucin secretion, mucosal cell shedding, cell proliferation and antioxidant activity in rats. BME 20 mg/kg showed no effect on acid-pepsin secretion, increased mucin secretion, while it decreased cell shedding with no effect on cell proliferation. BME showed significant antioxidant effect per se and in stressed animals. Thus, the gastric prophylactic and curative effects of BME may be due to its predominant effect on mucosal defensive factors.     

Studies of the seminal receptacle of the crab Portunus sanguinolentus (Portunidae: Brachyura)

The seminal receptacle or spermatheca of Portunus sanguinolentus consists of two parts--an anterior glandular and a posterior chitinous part. The chitinous part continues as the oviduct, which opens on the sternite of the sixth thoracic segment. Significant morphological and histological differences were observed between the spermatheca, as well as the oviduct, of mated and unmated crabs. In mated crabs the spermatheca is much more bulging, owing to receipt of a copious supply of seminal products, and its cells are hyperactive. Further stages of ovarian development were observed as indicators of sequential changes in the spermatheca. The secretory cells gradually disintegrate by way of holocrine secretion; this results in cellular stratification and the formation of distinct furrows in the chitinous posterior part.     

Observations on the nature of neurosecretion in the marine crab Portunus sanguinolentus (Herbst) (Crustacea: Brachyura)

Several types of NS cells were identified in Portunus sanguinolentus--five types (A, A', B, C and D) in the brain and thoracic ganglion, four types (A, B, C and D) in the commissural ganglia and four types (alpha, beta, gamma and delta) in the optic ganglia. The distribution of these NS cells is described. Cytochemically, the neurosecretory material in the NS cells has a carbohydrate moiety and is rich in disulphide groups, lipids, phospholipids and RNA. It contains a small amount of sulphydryl groups and protein-bound NH2 groups, but no tyrosine or tryptophan. The NS activity of the brain was found to be closely associated with the reproductive and moult cycles. Just before the initiation of vitellogenesis and moulting the NS cells display secretory hyperactivity. Axonal transport of NS material was also observed in the NS cells.     

Restriction endonuclease resistant chromatin in human chromosomes

Summary The recent addition of restriction endonucleases in obtaining selective bands in the human genome has added a new dimension to molecular genetics. However, a considerable discrepancy exists in banding patterns produced by AluI in chromosomes 19 and 20, by MboI in chromosomes 4, 5, 8, 21 and 22 and by RsaI in chromosomes 12, 21 and 22. The principal causes of these differences are highlighted.     

Calmodulin supports the force-generating function in desensitized muscle fibers

Externally added calmodulin (CaM) restored Ca2+ regulation for the tension development by skeletal muscle fibers of hamster and rabbit desensitized by the troponin C (TnC) extraction treatment. CaM produced this action by combining with the TnC-denuded sites in the fiber. However, the binding properties differed strikingly from TnC: unlike TnC, CaM binding required the continued presence of Ca2+ and the bound portion was completely released with EGTA in the physiological milieu. The maximal uptake was 1.7 g of CaM/kg of muscle in the present study. The apparent Ca2+ sensitivity for force development with 200 micrograms/ml CaM in the solution was lower than in the native fiber or in the TnC-loaded fiber. The apparent association constant for CaM binding to the TnC-denuded sites was found as 4.9 x 10(5) M-1, and the extrapolated maximum force (Fmax) with CaM was close to PO. The intrinsic CaM level in intact muscle was also measured and was 18.6 mg/kg, amounting to about 1% of the total TnC or the CaM uptake by TnC-denuded fibers. The intrinsic CaM was not dislodged by EDTA treatment, indicating tight binding and suggesting that it exists in a separate pool from the vacated TnC sites adsorbing externally added CaM. The stringent Ca+ dependence of the CaM adsorption to TnC sites in the regulatory complex in the fiber supports the view that the evolutionary replacement of residues in the amino terminus helix portion of the "EF-hand" motif of site IV may be critical for the functional specialization by TnC.     

Immunohistochemical localization of bursin in epithelial cells of the avian bursa of Fabricius

Antibodies to the avian B-cell-differentiating hormone bursin (lysyl-histidyl-glycine amide) were raised in mice and rabbits by immunizing with bursin conjugates in Freund's adjuvant. Immunohistochemical staining with these bursin-specific antibodies was restricted to follicular and dendritic reticular epithelial cells of the bursa of Fabricius, and was not found in control avian tissues.     

Viral replication is required for induction of ocular immunopathology by herpes simplex virus.

Corneal infection of BALB/c mice with herpes simplex virus type 1 results in a chronic inflammatory response in the stroma termed herpetic stromal keratitis (HSK). This disease is considered to be immunopathological and mediated primarily by CD4+ T cells of the type 1 cytokine profile. However, the nature of the antigens, virus or host derived, which drive the inflammatory response remains in doubt. In this study, the relevance of infection with replicating virus for the subsequent development of HSK was evaluated with immunocompetent mice as well as with SCID mice reconstituted with herpes simplex virus-immune CD4+ T cells. In the corneas of immunocompetent mice, infectious virus, viral antigen, and mRNA expression were detectable for only a brief period of time (< or = 7 days postinfection), and all were undetectable by the time clinical lesions were evident (10 to 15 days). Viral replication, however, was necessary for the development of HSK in both models, since infection with UV-inactivated virus or with mutant viruses which were incapable of multiple rounds of replication in vivo failed to induce HSK. The inactivated and mutant viral preparations did, however, stimulate T-cell immune responses in immunocompetent mice. The results are discussed in terms of possible involvement of host antigens exposed in response to transient progeny virion replication in the immune-privileged cornea.     

Clustering in non-stationary environments using a clan-based evolutionary approach

 Clustering techniques are used to discover structure in data by optimizing a defined criterion function. Most of these methods assume that the data are stationary, and these techniques are based on gradient descent which converge to a locally optimal clustering. There are many potential applications that require clustering to be performed in non-stationary temporal environments. In this paper, we investigate the applicability of a clan-based evolutionary optimization method for clustering data in non-stationary environments. Due to the stochastic nature of the technique, the problem of becoming entrapped in local optima is avoided, and the method can converge to (nearly) optimal clusters. Different cases are considered in the experiments, and the results demonstrate the efficacy of the evolutionary approach for clustering time-varying data. Received: 7 September 1994/Accepted in revised form: 28 March 1995     

Neuroanatomy of the central nervous system of the wandering spider,Cupiennius salei (Arachnida,Araneida)

Summary In Cupiennius salei (Ctenidae), as in other spiders, the central nervous system is divided into the supraoesophageal ganglion or brain and the suboesophageal ganglia (Fig. 1). The two masses are interconnected by oesophageal connectives. The brain gives off four pairs of optic and one pair of cheliceral nerves. From the suboesophageal ganglia arise a pair of pedipalpal, four pairs of leg, and several pairs of opisthosomal nerves (Fig. 2). 1. Cell types. In the brain a total of 50900 cells were counted, in the suboesophageal ganglia 49000. They are all monopolar cells, found in the ganglion periphery and may be classified into four types: (a) Small globuli cells (nuclear diameter 6–7 m) forming a pair of compact masses in the protocerebrum (Fig. 10b); (b) Small and numerous cells (cell diameter 12–20 m) with processes forming the bulk of the neuropil in the brain and suboesophageal ganglia; (c) Neurosecretory cells (cell diameter ca. 45 m) in the brain and suboesophageal ganglia; (d) Large motor and interneurons (cell daimeter 40–112 m), mostly in the suboesophageal ganglia (Figs. 10a and c). 2. Suboesophageal mass. The cell bodies form a sheet of one to several cell layers on the ventral side of each ganglion and are arranged in groups. Three such groups were identified as motor neurons, four as interneurons. At the dorsal, dorso-lateral, and mid-central parts of the ganglion there are no cell somata. The fibre bundles arising from them form identifiable transverse commissural pathways (Fig. 9b). They form the fibrous mass in the central part of the suboesophageal mass.Neuropil is well-formed in association with the sensory terminations of all major nerves (Fig. 9a). As these proceed centrally they break up into five major sensory tracts forming five layers one above the other. There are six pairs of additional major longitudinal tracts arranged at different levels dorsoventrally (Fig. 8). They ascend into the brain through the oesophageal connectives and terminate mostly in the mushroom bodies and partly in the central body. 3. Protocerebrum. Fine processes of the globuli cells form the most important neuropil mass in the fibrous core, called the mushroom bodies. These consist of well developed glomeruli, hafts, and bridge which are interconnected with the optic masses of the lateral eyes and most fibre tracts from the brain and suboesophageal mass (Fig. 7). The median eye nerves form a small optic lamella and optic ganglia, connected to the central body through an optic tract. Each posterior median and posterior lateral eye nerve ends in large optic lamellae (Fig. 13a). These are connected through chiasmata to a large optic mass where fibres from globuli cells form conspicuous glomeruli. There are 10–12 large fibres (diameter 9 m) of unknown origin on each side, terminating in the optic lambella of the posterior lateral eye.The central body, another neuropil mass (Fig. 13b) in the protocerebrum, is well developed in Cupiennius and located transversely in its postero-dorsal region (Fig. 10d). It consists of two layers and is interconnected with optic masses of the median and lateral eyes through optic tracts. Fibre tracts from the brain and suboesophageal mass join the central body.     

Fruit dimorphism inPhaseolus sublobatus (Fabaceae) and its evolutionary significance

Populations of the annualPhaseolus sublobatus from different ecogeographical zones are genetically differentiated. In twelve populations from the western ghats (Maharashtra range) chasmogamous flowers are arranged in peduncled capitate racemes borne in leaf axils of higher nodes. One population (Poona Race S₄) has additional inflorescences, also with chasmogamous flowers, on the main axis between the cotyledonary node and the ground. When the pods of these flowers ripen, the inflorescence gradually coils and, eventually, gets bury the fruits in the soil. This phenomenon is not known in any other plant.—The seed-coat patterns as revealed by SEM, and germination behaviour of both aerial and subterranean seeds are similar, and both types of seeds lack dormancy.—Heavy seed predation selection pressure is probably the principal cause for the evolution of fruit dimorphism inP. sublobatus. The origin of geocarpy in relation to fruit dimorphism and seed predation is discussed.