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S Hasan

Publications and source records attributed to S Hasan.

At least 37 records · Page 2Linked to original sources
PubMed1998

Novel antipsychotics and the neuroleptic malignant syndrome: a review and critique.

OBJECTIVE: The authors' goal was to analyze reported cases of neuroleptic malignant syndrome in patients given clozapine and risperidone. METHOD: They assessed 19 cases of clozapine-induced neuroleptic malignant syndrome and 13 cases of risperidone-induced neuroleptic malignant syndrome against three criteria sets and against extent of exclusionary workup and then designated them as high or low probability of being neuroleptic malignant syndrome. RESULTS: Nine of the 19 cases of clozapine-related neuroleptic malignant syndrome and eight of the 13 cases of risperidone-related neuroleptic malignant syndrome were designated as having high probability of being neuroleptic malignant syndrome. The remainder were designated as having low probability because presentations were not linked to treatment or failed to meet criteria for the syndrome. CONCLUSIONS: Neuroleptic malignant syndrome can occur in patients given atypical antipsychotics and resembles "classical" neuroleptic malignant syndrome. However, side effect profiles overlap considerably with neuroleptic malignant syndrome criteria, and atypical antipsychotics may cause neurotoxicities unrelated to (but misattributed as) neuroleptic malignant syndrome. Insufficient evidence exists for "atypical" neuroleptic malignant syndrome with novel antipsychotics.

Adolescent↗
PubMed1996

IGF-I stimulation of muscle protein synthesis in the awake rat: permissive role of insulin and amino acids.

Infusion of insulin-like growth factor I (IGF-I) lowers plasma amino acid and insulin concentrations, which may limit the capacity of IGF-I to promote muscle protein synthesis in vivo. We measured heart and skeletal muscle incorporation of continuously infused L-[ring-2,6-3H]phenylalanine in awake postabsorptive rats receiving 4-h intravenous infusions of saline (n = 11), IGF-I (1 microgram.kg-1.min-1) with (n = 10) or without (n = 11) amino acid replacement, or IGF-I with insulin replacement (n = 8). There were no significant increases in muscle protein synthesis during the infusion of IGF-I alone, which was associated with decreases in both plasma insulin (52 +/- 5%, P < 0.001) and amino acids (25 +/- 5%, P < 0.05). When IGF-I was given together with amino acids, protein synthesis was significantly increased in gastrocnemius (4.7 +/- 0.4 vs. 2.5 +/- 0.3%/day, P < 0.001), oblique (4.5 +/- 0.4 vs. 2.8 +/- 0.4%/day, P < 0.05), and soleus (8.8 +/- 0.7 vs. 6.4 +/- 0.3%/day, P < 0.01) and tended to be higher than saline control values in heart (10.9 +/- 0.9 vs. 8.8 +/- 0.7%/day, P = 0.08). Amino acid replacement prevented plasma concentrations from falling and also blunted the decline in plasma insulin (22 +/- 5%, P < 0.01 vs. IGF-I alone). When IGF-I and insulin replacement were given, protein synthesis was increased in heart (13.0 +/- 0.6%/day), gastrocnemius (4.7 +/- 0.4%/day), and oblique (4.5 +/- 0.4%/day) (P < 0.001 for each, compared with saline). We conclude that the action of IGF-I to acutely stimulate muscle protein synthesis in the awake rat is limited by the fall in circulating insulin and/or amino acid concentrations that accompanies IGF-I infusion in vivo and is prevented by co-infusion of insulin or amino acids.

Amino Acids↗
PubMed1995

Isolation and characterization of Cajanus cajan lectin.

Cajanus cajan lectin was isolated by ammonium sulfate fractionation and affinity chromatography on an IgM-Sepharose 6B column. Gel filtration and SDS-PAGE showed size homogeneity of the lectin. The lectin with M(r) 18,000 on SDS-PAGE had gel filtration behavior which was consistent with a molecular weight of 39 kDa and a Stokes radius of 2.74 nm. The results showed that the lectin is a dimer composed of identical subunits with N- and C-terminal residues of threonine and alanine, respectively. The glycoprotein lectin contained 3% concanavalin A-reactive neutral carbohydrates. Its amino acid composition is characterized by high contents of acidic amino acids. The number of tyrosine and tryptophan residues per mole of the lectin was determined to be 14 and 4, respectively, by spectrophotometry. Results on the effects of large numbers of saccharides on lectin-mediated hemagglutination and lectin-IgM precipitation showed that the C. cajan lectin was specific for mannose and glucose. A comparative study of the properties of C. cajan lectin and concanavalin A is also presented.

Amino Acids↗
PubMed1995

Laryngeal carcinoma ex-papilloma in a non-irradiated, non-smoking patient: a clinical record and review of the literature.

Malignant transformation of respiratory papillomata is not uncommon in the presence of precipitating factors such as tobacco smoking and therapeutic irradiation. Respiratory papilloma changing to carcinoma in the absence of smoking and irradiation is seldom seen, with only about 20 documented cases presented in the literature. Here we report one such case in a 30-year-old male patient.

Adult↗
PubMed1995

Serial magnetic resonance imaging in isolated angiitis of the central nervous system.

Isolated angiitis of the central nervous system (IACNS) is a rare form of vasculitis restricted to the CNS. We report serial MRI findings in a biopsy-proven case of IACNS. MRI showed extensive white matter and subcortical disease. Before specific treatment, neuroimaging showed the development of new lesions corresponding with an overall progressive clinical course of the illness; the post-treatment MRI showed improvement.

Brain↗
PubMed1994

An upstream NF-Y-binding site is required for transcriptional activation from the hst promoter in F9 embryonal carcinoma cells.

Expression of hst (k-FGF, FGF-4), a member of the fibroblast growth factor gene family, is restricted to early stages of developing embryos and to embryonal carcinoma cells. In F9, which is a prototype of embryonal carcinoma cells expressing hst, the expression of hst gene is positively regulated by a downstream octamer motif that functions as an enhancer. We have investigated, by chloramphenicol acetyltransferase (CAT) reporter fusion gene analysis in F9, the cis-acting regulatory element within the hst promoter region that interacts with this enhancer. Electrophoretic mobility shift assay and methylation interference analysis showed that the hst promoter contains, in a segment termed Y, the sequence 5'-CTGATTGGCA-3', which closely resembles the consensus binding motif for the CCAAT-binding factor NF-Y. Deletions or mutations in this element substantially reduced expression of hst-CAT constructs. The nuclear factor binding to the Y segment of the hst promoter was indistinguishable from NF-Y, as inferred from interactions with specific anti-NF-Y monoclonal and polyclonal antibodies. We conclude that the expression of the hst gene in F9 is positively regulated by the coordinated interaction between an NF-Y-binding site and an octamer motif.

Animals↗
PubMed1994

Regulatory sequences required for hst-1 expression in embryonal carcinoma cells.

The hst-1 gene, which is implicated in mammalian embryonic development and morphological transformation of NIH3T3 cells, is expressed in undifferentiated F9 cells, but not in differentiated F9 and other well-differentiated cells, such as PYS-2, NIH3T3 and HeLa cells. An octamer element present in the 3' untranslated region acts as an enhancer. Although Oct3 is down-regulated when F9 cells are differentiated, transient expression of Oct3 did not enhance the hst-1 promoter activity in HeLa, NIH3T3 or PYS-2 cells. Thus, the role of Oct3 on hst-1 expression remains elusive, and an additional transcription factor which interacts may regulate hst-1 transcription in association with Oct1, Oct3 or both.

3T3 Cells↗
PubMed1994

Pulmonary alveolar microlithiasis with pectus excavatum. Case report.

Pulmonary alveolar microlithiasis is a rare disease of unknown etiology. There is a formation of calcific bodies within the alveoli. The X-Ray shows extensive infiltration of both lungs. So far less than 100 cases were reported. However, we are unware of a case with pectus excavatum. In this report we discuss a case of pulmonary alveolar microlithiasis with pectus excavatum, and its treatment and medical intervention.

Adult↗
PubMed1993

Terguride as a new anti-hyperprolactinemic agent: characterization in rats and dogs in comparison with bromocriptine.

Terguride, a derivative of the ergot alkaloid, was characterized as a new anti-hyperprolactinemic agent in rats and dogs in comparison with bromocriptine. Terguride was found to bind selectively to the pituitary dopamine D2-receptors with a high affinity (Kd = 0.39 nM). In reserpinized rats, terguride at 0.03 mg/kg, p.o. significantly reduced the serum prolactin (PRL) level. The PRL lowering effect and the effective dose were longer lasting and about 30 times lower than those of bromocriptine, respectively. In rats bearing estrogen-induced pituitary prolactinoma, chronic terguride induced shrinkage of the prolactinoma as well as reduction of the high serum PRL level. In lactating rats, terguride (1.0 mg/kg, s.c.) reduced milk production in the mammary gland, whereas bromocriptine showed no significant effect up to 10 mg/kg, s.c. Terguride (10 mg/kg, p.o.) did not induce any stereotypy and hypermotility in reserpinized rats, while bromocriptine induced both stereotypy and hypermotility significantly at 10 mg/kg, p.o. In dogs, terguride, like bromocriptine, reduced the serum PRL level, but did not affect the serum levels of growth hormone and luteinizing hormone. In dogs, bromocriptine induced both emesis and PRL-lowering at almost the same dose, whereas emesis-inducing doses of terguride were about 100 times higher than the PRL-lowering dose. These results suggest that terguride as a dopamine D2-agonist is a potent inhibitor of PRL secretion with less neurotropic side effects compared to bromocriptine, and thus a useful drug for the treatment of galactorrhea and hyperprolactinemia including prolactinoma.

Animals↗
PubMed1992

Gamma-vinyl GABA prevents hippocampal and substantia nigra reticulata damage in repetitive transient forebrain ischemia.

GABAergic inhibitory mechanisms may offer protection to neurons after global ischemia. We tested the effects of gamma-vinyl GABA, a GABA-transaminase inhibitor, via continuous infusion in the third ventricle (Alza pumps) in a gerbil model of repetitive forebrain ischemia. We used two episodes of 3 min duration with a 'reperfusion' interval of 1 h between the insults. Histological analysis was done with silver staining 5 days after the insult. Our results show that there is significant protection of the hippocampus CA1 region and substantia nigra reticulata in treated animals compared to controls. An increase in GABA levels, decrease in glutamate, or mild hypothermia, may be potential mechanisms for this protection. GABAergic agents may prove useful agents in repetitive ischemia.

4-Aminobutyrate Transaminase↗
PubMed1992

Chondrosarcoma of the hyoid.

Two cases of chondrosarcoma of the hyoid bone are described. They were managed with surgical resection and postoperative radiotherapy. These patients are disease free at 26 months and 15 months respectively.

Adult↗
PubMed1992

Neck metastasis from an occult primary--the Kidwai experience.

This study highlights our treatment policy in 26 cases of epidermoid metastatic carcinoma in the neck from a primary deemed occult after exhaustive examination of the Upper Aero-digestive Tract (UADT). Planned Radical Neck Dissection (RND) and post-operative radiotherapy (RT) has been the favoured approach in all neck nodes deemed resectable and a loco-regional control rate of 64% was obtaining using this combined modality approach. Pre-operative RT was utilised in three cases with nodal disease of borderline resectability and loco-regional control was achieved in one case. Three cases of massive neck metastasis initially deemed unrectable became amenable to surgical salvage after Radical RT with concurrently administered chemotherapy. Only one of these remained disease free. Overall loco-regional control rate of 55 per cent could be achieved in 20 evaluable patients followed up for two years--three years (mean 30.5 months). Regional failures were noted in 25 per cent of patients while distant spread occurred in 15 per cent, thus accounting for an overall failure rate of 40 per cent. Manifest primaries were documented in 20 per cent, half of which could be salvaged and successfully controlled.

Adult↗
PubMed1991

Regulation of human hst expression by an enhancer element residing in the third exon.

The hst gene is exclusively expressed in undifferentiated embryonal carcinoma cell lines and at a limited stage of embryonal development. Two DNase I-hypersensitive sites were mapped in the 3' region (approximately 3.5 and 4.5 kb downstream of the translational initiation site) of the human hst gene, irrespective of the presence or absence of hst mRNA in the cells. A DNA fragment containing one of these DNase I-hypersensitive sites (at around 3.5 kb relative to the translational initiation site) showed enhancer activity when tested by chloramphenicol acetyltransferase (CAT) assay. These results strongly suggest that an enhancer element(s) exists in the third exon of the hst and that the expression of the hst may be regulated by the presence or absence of a putative protein factor(s) which binds to the enhancer.

3T3 Cells↗
PubMed1991

Provirus integration at the 3' region of N-myc in cell lines established from thymic lymphomas spontaneously formed in AKR mice and a [(BALB/c x B6)F1----AKR] bone marrow chimera.

Among 18 thymic leukemia cell lines which have been established from spontaneous thymic lymphomas in AKR mice as well as in bone marrow chimeras which were constructed by transplanting allogeneic bone marrow cells into irradiated AKR mice, three proviral integration sites were identified; near c-myc, N-myc and pim-1 loci. No integration site specific for chimeric leukemia cell lines was found. In three thymic leukemia cell lines which contained rearranged N-myc genes, insertions of long terminal repeats (LTRs) of murine leukemia viruses were detected at 18 or 20 bp downstream of the translational termination codon. These results demonstrate that the 3' region of the N-myc gene is one of the integration targets for murine leukemia viruses in spontaneous thymic lymphomas. In these three cell lines, N-myc mRNA was stably transcribed and transcription of c-myc mRNA was down-regulated. The integrated murine leukemia viruses in AKR thymic leukemia were most likely AKV, though the DNA sequence of the LTR inserted in the genome of a leukemic cell line from [(BALB/c x B6)F1----AKR], CAK20, was different from LTRs of murine leukemia viruses so far reported.

Antigens, Surface↗