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Biomedical subjects

S Haider

Publications and source records attributed to S Haider.

17 recordsLinked to original sources
PubMed1992

Spontaneous extrusion of an intraocular lens implant.

A 51-year-old man with ankylosing spondylitis had intracapsular cataract extraction and anterior chamber lens implantation in the left eye in 1985. He had localized sclerokeratitis around the corneal section and a protracted anterior uveitis in the immediate postoperative period. He developed a spontaneous extrusion of the implant in 1991 (six years later). The extrusion was through a site 1.5 mm posterior to the previous surgical section. There was no corneal decompensation or corneal melt and no history of trauma. Signs of localized scleritis were present. It is suggested that anterior chamber lens implantation should be avoided under these circumstances.

Anterior Chamber↗
PubMed1992

Oocyte maturation in Clarias batrachus: in vitro effect of various gonadotropins and homologous pituitary homogenate.

The effects of five different gonadotropins and homologous pituitary homogenate (HP) on germinal vesicle breakdown (GVBD) were investigated in vitro using folliculated oocytes of Clarias batrachus. Among all the gonadotropins, salmon gonadotropin (SG-G100) was the most potent in vitro inducer of oocyte maturation. At concentrations of 1, 0.1, 0.01 and 0.001 microgram/ml it induced 86.98 +/- 2.71, 68.74 +/- 2.85, 44.56 +/- 1.75 and 25.90 +/- 2.36% GVBD. Next to SG-G100 in inducing GVBD was luteinizing hormone (LH) which was consistently found to be effective at all the concentrations used. Human chorionic gonadotropin was also found to be effective at all the concentrations but when compared to SG-G100 and LH, it was less effective. Follicle stimulating hormone and pregnant mare serum gonadotropin were found to be effective at higher concentrations but were ineffective at the lowest concentration. HP treatment resulted in a significant number of GVBD at all the three concentrations used.

Animals↗
PubMed1991

Testis and epididymis of the Indian wall lizard (Hemidactylus flaviviridis): effects of flutamide on FSH and testosterone influenced spermatogenesis, Leydig cell, and epididymis.

To determine the separate spermatogenic actions of FSH and testosterone, adult male lizards Hemidactylus flaviviridis with recrudescent testes were administered the non-steroidal antiandrogen flutamide either alone or in combination with FSH or testosterone, and the histology and histochemistry of the testes and ductus epididymides were studied. Flutamide-treated animals displayed a marked hypertrophy of Leydig cells. A few spermatids were also seen in testis of more than half the animals treated with flutamide. Flutamide also produced a significant increase of primary spermatocytes; no spermatids were observed in controls. A significant inhibition of spermatogenesis was noted in lizards treated either with testosterone alone or in combination with flutamide. Ovine FSH treatment caused a significant stimulation of spermatogenesis, as indicated by the increase of primary and secondary spermatocytes and the transformation of secondary spermatocytes into spermatids or, in a few cases, into spermatozoa. A considerable depletion of sudanophilic lipid and moderate delta 5-3 beta-hydroxysteroid dehydrogenase activity was noted in the Leydig cells of FSH-treated animals indicating enhanced steroidogenesis. Similar results were obtained when lizards were treated with flutamide + FSH. The effects of simultaneous treatment of flutamide with FSH or testosterone on ductus epididymidis revealed that flutamide markedly inhibited the epithelial cell height and lumen diameter with a loss of luminal content when compared to FSH or testosterone-treated lizards.

Animals↗
PubMed1990

Further experimental evidence in support of the involvement of ovarian follicles in oocyte maturation of the Indian catfish, Mystus vittatus.

The role of the ovarian follicular layer in the oocyte maturation of the Indian catfish, Mystus vittatus, was investigated in vitro using cyanoketone and epostane (specific inhibitors of the 3 beta-hydroxysteroid dehydrogenase enzyme system). Folliculated oocytes incubated with luteinizing hormone (LH) at the concentration of 10 micrograms/ml induced 67.7 +/- 1.5% of germinal vesicle breakdown (GVBD). When the oocytes were incubated with LH + cyanoketone or epostane, there was a significant drop in the frequency of GVBD. It revealed that the maturational response of M. vittatus oocytes to LH depends on the synthesis of delta 4 steroids (probably 17 alpha,20 beta-dihydroxy-4-pregen-3-one; 17 alpha,20 beta-diOHprog) from the follicular layer since both the inhibitors failed to abolish the maturational effect of 17 alpha, 20 beta-diOHprog (the most potent maturation-inducing steroid for this species).

Androstenols↗
PubMed1990

Trace element studies on Karachi populations. Part V: Blood lead levels in normal healthy adults and grammar school children.

Blood lead levels of healthy Karachi population were estimated. Mean levels for males, females, soldiers and school children were 34.4, 31.8, 29.9 and 38.2 micrograms/dl respectively. About 93% cases of either sex had elevated lead levels, of whom 30% males and 10% females had levels above the safety limits (40 micrograms/dl). Soldiers living in relatively pollution free area though had levels lower than the rest of the population but 91% had levels over 25 micrograms/dl and only two had acceptable levels. Ninety-two percent children showed levels above 25 micrograms/dl with a large number having levels over 40 micrograms/dl. A very small percentage had normal levels. Pollution by traffic exhaust was assumed to be the principal cause for these high levels.

Adolescent↗
PubMed1979

An in situ study of the hypothalamo-neurohypophysial complex of the freshwater teleost Ompok bimaculatus (Bloch) with a note on the tetrapodan features of its vascularization.

In Ompok bimaculatus the neurosecretory axons of both the pars magnocellularis and pars parvocellularis component of the nucleus preopticus contribute to the formation of the left and right main tracts. At rostral levels, one third of the tracts are loosely built forming a king of curtain, while they become more compact at caudal levels. The caudal two thirds of the main tracts give off several pairs of lateral tracts which join at the midline to form the paired median tracts. The median and the main tract jointly enter the pituitary as a common tract which, on entering the proximal pars distalis, separates into two and enters the pars intermedia. The hypothalamic and the hypophysial arteries take their origin from the internal carotid artery. The former contribute to the formation of the primary capillary plexus of the median eminence, whereas the latter enter the pituitary directly and ramify in the neuroadeno-interface. The primary capillary plexus is in close topographical contact with the neurosecretory axonal complex where the median and common tracts are formed. At this site at least some axons might have their endings on the capillary plexus. Thus, this region my be comparable in structure to the median eminence of the tetrapods. The neurons of the nucleus lateralis tuberis of O. bimaculatus are AF-positive. The infundibular cavity extends into the main neurohypophysial trunk and is lined by ependymal cells like the third ventricle.

Animals↗
PubMed1979

Occurrence of oocytes in the liver of the percoid fish, Trichogaster fasciatus (Bloch and Schneider) and its probable significance.

Out of 500 Trichogaster fasciatus examined in one fish stage I and II oocytes were noticed in the liver and its blood sinuses. Apparently this is the first record of such occurrence. It is highly suggestive of the vascular migration of the germ cells enroute to the genital ridge. Possibly due to unknown reasons some might have been stuck up in the liver which is highly vascular.

Animals↗
PubMed1978

Experimental and seasonal changes in the pituitary of the Teleost Heteropneustes fossilis (Bloch).

The pituitary of Heteropneustes fossilis is composed of a glandular adenohypophysis and a neurohypophysis (NH). The adenohypophysis is divided into three regions namely: rostral and proximal pars distalis (RPD and PPD) and pars intermedia (PI) consisting of seven different cell types. The RPD is made up of two cell types, the erythrosinophilic acidophils which form the major component of this region and H. Pb positive cells which border the NH. The latter exhibited hypertrophy during spawning and in radiothyroidectomised fishes. The erythrosinophils and H. Pb positive cells can be compared to the lactotrophs and corticotrophs described in the literature. The PPD is composed of three cell types: thyrotrophs, gonadotrophs and acidophils. The gonadotrophs and thyrotrophs readily take up the PAS, aldehyde fuchsin and anilin blue. The gnadotrophs show a marked numerical increase and hypertrophy in the breeding season, whereas they are small and comparatively few in nonbreeding season. In radiothyroidectomised fish the thyrotrophs show hypertrophy and degranulation and tendency to migrate into all the component parts, reaching upto the stalk region. In the control only few cells compared to thyrotrophs are seen in the NH and PI. The PI consists of H. Pb and PAS positive cells. They may be involved in the secretion of melanocyte stimulating hormone (MSH) and osmoregulation as suggested in the literature.

Animals↗
PubMed1978

Micromorphology of the median eminence in the percoid fish, Trichogaster fasciatus (Bloch and Schneider).

The pituitary of Trichogaster fasciatus is devoid of a distinct stalk and is closely attached to the floor of the brain. The third ventricle is in wide communication with the anterior neurohypophysis adjacent to the pars distalis. The subterminal region of the hypothalamus and the anterior neurohypophysis forms the median eminence. Structurally this region can be compared to the median eminence of tetrapods as it is differentiated into ependymal, fibrous and reticular layers. A close morphological contact between the stainable neurosecretory and silver positive axons with the capillary plexus and accumulation of neurosecretory material around the capillary network suggest the presence of an incipient tetrapodan type of median eminence in this species.

Animals↗
PubMed1977

Hypothalamo-hypophysial neurosecretory system of the teleost Trichogaster fasciatus (Bloch & Schneider) with a note on it's vascularization.

The hypothalamo-hypophysial neurosecretory (HN) complex of Trichogaster fasciatus is described with the help of in situ staining technique and tissue sections. The neurons of the nucleus preopticus (NPO) give rise to fine neurosecretory axons which form the left and right main tracts. The bulk of the tracts come laterally and enter the middle portion of the neurohypophysis. However, some of them spread out and penetrate the rostral neurohypophysis as well. Hypophysial artery contributes to the formation of primary capillary plexus (PCP) which extends from the subterminal region to the extremity of the anterior neurohypophysis. Structurally, the subterminal region and the anterior neurphoyophysis can be compared to the median eminence (ME) of tetrapods as it is differentiated into ependymal, fibrous and reticular layers. Also, these areas have aboundant neurosecretory and silver positive axons suggesting the possibility of direct transmission of neurohormones into the blood.

Animals↗
PubMed1975

Antagonistic response of chlorpromazine and formalin in effecting quantitative changes in the neurosecretory material in the teleost Clarias batrachus (L.).

The hypothalamoneurohypophysial complex of Clarias batrachus maintains an appreciable quantity of neurosecretory material (NSM) under normal conditions. Stress caused by the injection of formalin depletes 70-90% of the stainable NSM from all the component parts of the neurosecretory system, namely the nucleus preopticus (NPO) the neurosecretory tract, and the neurohypophysis. Formalin apparently releases the NSM and stimulates the neurons of the NPO. Chlorpromazine (CPZ) treatment seems to cause quantitative increase of NSM throughout the neurosecretory complex. Simultaneous injection of CPZ and formalin showed that the formalin-induced depletion of NSM could be inhibited by CPZ.

Animals↗
PubMed1975

Pituitary cytology of radiothyroidectomised teleost Heteropneustes fossilis (Bloch.).

The pituitary of Heteropneustes fossilis is divisible into rostral (RPD) and proximal (PPD) pars distalis, and pars intermedia (PI). Neurohypophysis extensively ramifies in the PI. The RPD is formed of acidophilic prolactin cells and lead hematoxylin (H. Pb) positive ACTH cells. The latter is arranged around the neurohypophysial extensions. The PPD is comprised of thyrotrophs (TSH) and gonadotrophs which are stainable with PAS, AF, and aniline blue. Acidophilic somatotrophs (STH) and chromophobes are scattered throughout the PPD. In the pars intermedia PAS positive and H. Pb positive cells are present. The latter is believed to secrete MSH whereas the function of the former is yet to be confirmed. In the partly and completely thyroidectomised H. fossilis the TSH cells exhibited marked hypertrophy. They are located in the middle of the PPD flanked by the gonadotrophs on either side. Hypertrophy of the ACTH cells were also evident. But the other cell types did not show any marked changes as compared to the controls.

Animals↗
PubMed1975

Alcohol inhibition of formalin induced depletion of neurosecretory material in the teleost Clarias batrachus (L).

In the normal C. batrachus a fair amount of stainable neurosecretory material (NSM) is always present in all the component parts of the hypothalamo-neurohypophysial (HN) complex. When formalin was injected intraperitoneally 70 to 90% of the NSM was depleted from the HN complex. When ethyl alcohol was administered immediately after formalin treatment, the depletion of NSM was inhibited, and their staining intensity could be compared with those of untreated controls.

Animals↗
PubMedDate not supplied

Antibodies to lactate dehydrogenase of Plasmodium knowlesi are specific to Plasmodium species.

Polyclonal immune monkey serum raised against schizonts of Plasmodium knowlesi (H-strain) showed the presence of antibodies to lactate dehydrogenase (LDH) of P. knowlesi by immunodot enzyme staining method. The anti-LDH antibodies are most probably directed towards an epitope distinct from the catalytic site as shown by the specific enzyme staining of LDH after binding with antibody on nitrocellulose paper. These antibodies showed reactivity with LDH from different strains (H, P and W1 strains of P. knowlesi) and species (P. cynomolgi B, P. berghei, P. yoelii, P. falciparum and P. vivax) of malarial parasites but did not cross-react with three isoenzymic forms of mammalian LDH (A4, B4 and C4) as well as with LDH from some protozoan and helminth parasites. These findings suggest that the anti-LDH antibodies have defined specificity to Plasmodium spp.

Animals↗