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N Haider

Publications and source records attributed to N Haider.

31 records · Page 2Linked to original sources
PubMed1992

Report on the sequence of DQB1*0301 gene in ocular cicatricial pemphigoid patients.

Ocular cicatricial pemphigoid (OCP) is an autoimmune disease that affects the conjunctiva and other mucous membranes. Major histocompatibility complex (MHC) class II genes are important in autoimmunity because the antigen is presented to the T cell receptor in association with these molecules. A highly statistically significant association has been observed between patients with OCP and DQw7 (DQB1*0301) gene. DNA sequences of the second and third exons of the DQB1*0301 gene were determined in three OCP patients and compared with a control homozygous cell line for DQw7 from the Tenth International Histocompatibility Workshop. The sequences were identical in the patients studied and reference cell line. This data indicates that DQB1*0301 may only partly provide the enhanced susceptibility to get OCP and that another gene(s) in linkage disequilibrium with it and other factors may play an important role in the pathogenesis.

Amino Acid Sequence↗
PubMed1990

Characterisation of a repetitive DNA family from Entamoeba histolytica containing Saccharomyces cerevisiae ARS consensus sequences.

Several repetitive DNA families were identified in Entamoeba histolytica DNA digested with Sau3AI. Characterisation of one of these repetitive DNA families showed the presence of multiple copies of Saccharomyces cerevisiae autonomously replicating sequence (ARS) core consensus sequences. The E. histolytica ARS consensus sequences allowed a yeast-integrating plasmid, YIP5, to replicate autonomously in S. cerevisiae. A 'bent DNA' fragment was located in one member of this E. histolytica repetitive DNA family.

Animals↗
PubMed1989

Pyridazine analogues of biologically active compounds. Part 5: Novel potential cardiotonics of the amrinone type.

Preparation of a series of novel pyridazine derivatives structurally related to bipyridine cardiotonics, starting from 4-methylpyridazine or 4-acetylpyridazine, respectively, is described. As observed with compounds 8, 11 and 16, an enhancement of in vitro cardiotonic activity is associated with the replacement of one or both pyridine subunit(s) in amrinone or milrinone by a 1,2-diazine system.

Amrinone↗
PubMed1986

Effects of afternoon injections of O-acetyl-5-methoxytryptophol, melatonin or 5-methoxytryptophol in female Syrian hamsters.

Female Syrian hamsters were maintained in a 14:10 light: dark photoperiod (lights on 6 a.m.) and injected each afternoon between 4 p.m. and 6 p.m. with diluent or with 25 micrograms melatonin, O-acetyl-5-methoxytryptophol (aML) or 5-methoxytryptophol (ML). After 7 or 12 weeks of treatment, only the melatonin-treated hamsters were acyclic. Gross inspection of their ovaries revealed that they were smooth, brown, and devoid of corpora lutea and large follicles. Progesterone levels of the acyclic animals were midway between the high levels observed during estrus and postestrus and the low levels observed on cycle days 2 and 3. Additionally, the melatonin-treated hamsters had significantly reduced uterine weights and pituitary and plasma levels of prolactin. Hamsters treated with aML had significantly lower pituitary prolactin and plasma and pituitary levels of LH only at the 7 week timepoint. ML-treated hamsters had lower pituitary prolactin levels also at 7 weeks. The endocrine changes wrought by injections of aML and ML, however, were insufficient to ultimately affect vaginal cyclicity. In conclusion, it would appear that at the dose used and the time administered melatonin is the more active of the indoles tested in the female hamster, at least in terms of alterations in reproductive physiology.

Animals↗
PubMed1979

The effects of dexamethasone on the growth of gamma-irradiated tadpoles.

A plausible hypothesis as to the mode of action of dexamethasone (DXM) has been proposed. Growth of irradiated tadpoles of Bufo melanostictus, treated daily with the corticoid, is more suppressed. Compared with its antagonism with ACTH, its coordinate promotion of TSH production accelerates metamorphosis. This modulated feedback is consistent with the constant course of the hypothalamic nuclei influence upon the adenohypophyseal hormones.

Adrenocorticotropic Hormone↗
PubMedDate not supplied

ATP independent calcium transport and binding by basal plasma membrane of human placenta.

The transport of large amounts of Ca2+ by the plasma membranes of human placental syncytiotrophoblast is essential to the mineralization of the growing fetal skeleton. We have investigated transport by the basal (fetal-facing) plasma membrane (BPM). Ca2+ was taken up by purified BPM vesicles in a time-dependent manner and equilibrium attained in approximately 60 min. The apparent equilibrium space was many fold higher than that determined using other substrates (e.g. leucine), suggesting that Ca2+ is concentrated or bound within the vesicles. The more rapid uptake and exit in the presence of A23187 indicates that membrane transport is rate limiting and that Ca2+ is internalized within the membrane space. The initial rate of uptake was approximately by measurement during the first 2 s of incubation. Concentration dependence data were fit to a Michaelis-Menten model with one saturable site and diffusion (Km = 12 microM; Vmax = 4 nmol/min/mg; KD = 39 nmol/min/mg/mM). Saturable Ca2+ binding (Kd = 16 microM; Bmax = 3.4 nmol/mg) was of lower capacity than previously observed for microvillous membrane.

Adenosine Triphosphate↗