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Siddiqui BS, Begum S, Siddiqui S, Lichter W. Two cytotoxic pentacyclic triterpenoids from Nerium oleander. PHYTOCHEMISTRY 1995; 39:171-174. [PMID: 7786484 DOI: 10.1016/0031-9422(94)00855-n] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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202
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Khabar KS, Siddiqui S, Armstrong JA. WEHI-13VAR: a stable and sensitive variant of WEHI 164 clone 13 fibrosarcoma for tumor necrosis factor bioassay. Immunol Lett 1995; 46:107-10. [PMID: 7590904 DOI: 10.1016/0165-2478(95)00026-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Bioassaying tumor necrosis factor (TNF) relies not only on a sensitive but also on a stable cell line towards TNF action. A variant of WEHI 164 clone 13, WEHI-13VAR, was characterized by us. This variant demonstrated both stability and high sensitivity towards rTNF-alpha or rTNF-beta when assayed in the presence of actinomycin-D (AcD). Fifteen subclones were generated from WEHI-13VAR (rTNF-alpha; ED50 range: 0.005-0.065 ng/ml). No clones were found more sensitive than the AcD-treated WEHI-13VAR cell line. An important feature of this line is its stable sensitivity. The stability of the cell line sensitivity towards rTNF-beta was demonstrated in the presence of AcD over a period of 16 months with an average ED50 of 0.046 +/- 0.004 ng/ml. In conclusion, unlike other TNF-sensitive cell lines in which the sensitivity is lost or the stability is unknown, WEHI-13VAR provides a sensitive, reliable and stable bioassay system to detect cytotoxin, TNF-alpha, and TNF-beta.
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al-Dalaan A, al-Sedairy S, al-Balaa S, al-Janadi M, Elramahi K, Bahabri S, Siddiqui S. Enhanced interleukin 8 secretion in circulation of patients with Behçet's disease. J Rheumatol 1995; 22:904-7. [PMID: 8587080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE The pathogenesis of Behçet's disease (BD) has not yet been determined. Several hypotheses have been postulated and cytokines that control growth proliferation and hematopoiesis of progenitor cells play a role in relation to immune response and inflammatory dysfunction. We investigated whether cytokines play a role in pathogenesis of BD. METHODS We employed the quantitative sandwich enzyme immunoassay technique, in which antibody is already coated on the microtiter plate standard and samples are pipetted into the wells. Antigen present is bound by immobilized antibody. After incubation and washing steps, conjugate, which is enzyme linked polyclonal antibody specific for the antigen is added to the wells. Following a wash to remove any unbound antibody enzyme reagent, a substrate solution is added to the wells, and color develops in proportion to the antigen bound in the initial steps, which can be read in terms of optical density present in the standards and in the samples. RESULTS Of a total of 53 samples with BD, 33 (64%) had detectable levels of interleukin 8 (IL-8). Levels of IL-6, tumor necrosis factor alpha and interferon-gamma were not significantly elevated in patients with BD. CONCLUSION We found that IL-8 levels are higher in patients with active BD, and since IL-8 has a potent effect on the neutrophil, this cytokine most likely participates in the inflammatory response of this disease.
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Faizi S, Siddiqui BS, Saleem R, Siddiqui S, Aftab K, Gilani AH. Fully acetylated carbamate and hypotensive thiocarbamate glycosides from Moringa oleifera. PHYTOCHEMISTRY 1995; 38:957-63. [PMID: 7766390 DOI: 10.1016/0031-9422(94)00729-d] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Six new and three synthetically known glycosides have been isolated from the leaves of Moringa oleifera, employing a bioassay-directed isolation method on the ethanolic extract. Most of these compounds, bearing thiocarbamate, carbamate or nitrile groups, are fully acetylated glycosides, which are very rare in nature. Elucidation of the structures was made using chemical and spectroscopic methods, including 2D NMR techniques. Thiocarbamates showed hypotensive activity.
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Faizi S, Siddiqui BS, Saleem R, Siddiqui S, Aftab K, Gilani AH. Isolation and structure elucidation of new nitrile and mustard oil glycosides from Moringa oleifera and their effect on blood pressure. JOURNAL OF NATURAL PRODUCTS 1994; 57:1256-61. [PMID: 7798960 DOI: 10.1021/np50111a011] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Bioassay-guided analysis of an EtOH extract of Moringa oleifera leaves showing hypotensive activity led to the isolation of two nitrile glycosides, niazirin [1] and niazirinin [2], and three mustard oil glycosides, 4-[(4'-O-acetyl-alpha-L-rhamnosyloxy)benzyl]isothiocyanate [4], niaziminin A, and niaziminin B. Glycoside 2 is a new compound. Niaziminins A and B have previously been obtained from the left extract as a mixture, while compound 4 is new from this source. Structural determination was accomplished by means of spectroscopic methods including appropriate 2D nmr experiments and chemical reactions. This is the first report of the isolation of nitriles, an isothiocyanate, and thiocarbamates from the same plant species. Isothiocyanate 4 and the thiocarbamate glycosides niaziminin A and B showed hypotensive activity while nitrile glycosides 1 and 2 were found to be inactive in this regard.
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Khan KA, Khan SA, Khalid SM, Ahmed A, Siddiqui BS, Saleem R, Siddiqui S, Faizi S. In vitro studies of the antibacterial and antifungal activity of oxine and its derivatives. ARZNEIMITTEL-FORSCHUNG 1994; 44:972-5. [PMID: 7945545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Twenty-one derivatives of 8-hydroxyquinoline (oxine, 8H, CAS 148-24-3) were prepared and characterized by UV, IR, MS and NMR spectroscopy. Four of these derivatives, N-butyl, 8-butyloxyquinolinium bromide (HBD), 8-pentyloxyquinoline (HPEM), N-pentyl, 8-pentyloxyquinolinium bromide (HPED) and N-benzyl, 8-benzyloxy quinolinium chloride (HBED) are new and reported for the first time. The antimicrobial activity of these compounds was carried out in vitro against 11 Gram positive and 18 Gram negative bacteria, and 18 fungi including 9 dermatophytes, 7 other filamentous fungi and 2 Candida species. Three compounds namely, HPRD, HPED and HBED were found to possess significant antibacterial activity in order of HPED > HPRD > HBED, whereas 4 were found to possess significant antifungal activity in order of 8H > HT > HPEM > 8B.
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Siddiqui S, Usmanghani K, Shameel M. Sterol and Fatty Acid compositions of a marine alga bryopsis pennata (bryopsidophyceae, chlorophyta). PAKISTAN JOURNAL OF PHARMACEUTICAL SCIENCES 1994; 7:73-82. [PMID: 16414750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The green alga Bryopsis pennata Lamouroux, collected from the coast of Karachi, has been investigated for its sterol and fatty acid compositions. Four sterols and 19 fatty acids have been isolated from methanolic extract of this alga and identified by (1)H-NMR, El- & GC-MS techniques. The sterol having cholesta skeleton was found as major constituent (78.12%), while other three with ergosta skeleton occurred in traces (5-9%). Seven saturated fatty acids were present in greater quantity (72.58%) than 12 unsaturated ones (27.41%). The latter included 7 monoenoic, 2 dicnoic, 2 trienoic and 1 pentaenoic adds. Tricosanoic acid was found in the highest amount (30.24%), cyclopentenyl undecanoic and heneicosapentaenoic acids were the unique and rare fatty acids detected.
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Saeed SA, Simjee RU, Farnaz S, Gilani AH, Siddiqui S, Siddiqui BS, Begum S, Faizi S, Zia A. Inhibition of platelet aggregation and arachidonic acid metabolism by B-carboline alkaloids. Biochem Soc Trans 1993; 21:461S. [PMID: 8132029 DOI: 10.1042/bst021461s] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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209
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Bouchama A, al-Sedairy S, Siddiqui S, Shail E, Rezeig M. Elevated pyrogenic cytokines in heatstroke. Chest 1993; 104:1498-502. [PMID: 8222814 DOI: 10.1378/chest.104.5.1498] [Citation(s) in RCA: 129] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
STUDY OBJECTIVES Heatstroke, characterized by hyperthermia and neurologic abnormalities, can cause shock, adult respiratory distress syndrome, and multiorgan failure culminating in death. The mediation of metabolic changes and tissue damage is not fully understood. Recent evidence suggests the involvement of endotoxin, tumor necrosis factor alpha (TNF-alpha), and interleukin 1 alpha (IL-1 alpha) and we hypothesized that other pyrogenic cytokines may be implicated. DESIGN Prospective analysis. SETTING Heatstroke Center in Makkah (Mecca), Saudi Arabia. MEASUREMENTS AND RESULTS We measured plasma IL-1 beta, IL-6, and interferon gamma (INF-gamma) concentrations by enzyme-linked immunosorbent assay in 28 heatstroke patients at the time of hospital admission (precooling) and after complete cooling (postcooling), and in 10 normal control subjects. We measured C-reactive protein (CRP) as a marker of acute phase response and calculated severity of illness using the simplified acute physiology score. Twenty-five male and 3 female subjects had mean (+/- SEM) rectal temperature of 41.2 +/- 0.2 degrees C. IL-6, IL-1 beta, and INF-gamma concentrations were elevated in 100 percent, 39 percent, and 50 percent of patients to (mean +/- SEM) 220 +/- 44 pg/ml, 42 +/- 14 pg/ml, and 1,180 +/- 879 pg/ml, respectively (normal control values: < 3.5 pg/ml, < 4.5 pg/ml, < 20 pg/ml). The CRP value was elevated in 72 percent of patients to 152 +/- 40 mg/L (control value: 0 to 17 mg/L). The IL-6 concentrations correlated with severity of illness (r = 0.516, p = 0.03); two patients with the highest concentrations died. There was no significant correlation between circulating levels of IL-6, IL-1 beta, INF-gamma, and temperature, or between IL-6, IL-1 beta, and CRP. Postcooling, IL-6, and IL-1 beta were still above normal control values; INF-gamma could be detected in one patient only. CONCLUSION Our findings of elevated circulating IL-6, IL-1 beta, and INF-gamma in the presence of acute phase response, and correlation with severity of illness, suggest that these cytokines have a role in the pathogenesis of heatstroke, which could lead to new therapeutic strategies.
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Siddiqui BS, Adil Q, Begum S, Siddiqui S, Khan KA, Khan SA, Khalid SM. Synthesis of alkyl catechols and evaluation of their antibacterial and cyfotoxic activity. PAKISTAN JOURNAL OF PHARMACEUTICAL SCIENCES 1993; 6:53-69. [PMID: 16414739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
A series of potential biologically active mono-, di- and tetra- alkyl catechols were prepared through Friedel- Crafts alkylation of catechol, and evaluated for their antibacterial and cytotoxic activity. The mono-substituted alkyl derivatives showed maximum antibacterial activity in vitro which increased with the increasing length of the alkyl chains. Primary screening results indicated that all the monoalkyl derivatives except 4- (2-octyl) catechol inhibited the growth of B. bronchoseptica and maximum zones of inhibition were observed in case of monohexyl catechols (both n- and 2-hexyl) and monobenzyl derivative. In case of Gram-negative organisms growth of Kl. pneumoniae and A. calcoaceticus was inhibited by several derivatives. Mono-3-octyl-, monononyl- and monobenzyl catechols markedly inhibited the growth of Kl. pneumoniae. Mono-2-heptyl catechol inhibited the growth of six Gram-negative bacteria. Minimum inhibitory concentration of six most active compounds of the series was determined against Gram-positive and Gram-negative organisms; it ranged from < 100 mug/ml to l0 mug/ml. The antibacterial activity of catechol was not significant. Cytotoxicity test done by brine shrimp assays showed that the order of cytotoxicity decreases in going from mono- to tetra- alkyl catechols, and among the mono- alkyl products, a decrease in order of cytotoxicity was noted in going from mono-methyl catechol (LD(50) = 59) to monopentyl catechol (LD(50) = 173) after which the order of cytotoxicity gradually increased upto the largest alkyl substituent tested i.e. monononyl catechol (LD(50) = 114). Methyl and ethyl catechol, which were almost inactive in respect of their antibacterial activity possessed prononounced cytotoxicity as compared to higher homologues. Catechol itself did not show significant cytotoxicity (LD(50) = 393.27).
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Begum S, Adil Q, Siddiqui BS, Siddiqui S. Synthesis of 2β-Hydroxyursolic Acid and Other Ursane Analogs From Ursonic Acid. Aust J Chem 1993. [DOI: 10.1071/ch9931067] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Synthesis of the natural product 2β-hydroxyursolic acid (6) has been achieved through reaction of ursonic acid (1) with SeO2, and subsequent stereospecific reduction of the 2,3-diketo derivative (3) and its tautomer diosphenol (4), with NaBH4 under mild reaction conditions. Several other analogues (2), (5), (7) and (8) of the ursane series have also been obtained during these reactions.
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Bhatti AR, Wong JP, Siddiqui YM, Siddiqui S. A sensitive fluorogenic enzyme linked immunosorbent assay for the detection of Vipera russelli venom. NATURAL TOXINS 1993; 1:277-82. [PMID: 8167946 DOI: 10.1002/nt.2620010504] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A highly sensitive fluorogenic enzyme-linked immunosorbent assay (FELISA) has been adapted for the detection of Vipera russelli venom. The assay sensitivity was observed to be 0.1 pg/ml (1 x 10(-13) g/ml). Venoms from snakes of the Vipera group exhibited a high degree of cross-reactivity when tested with the antibody raised against V. russelli venom. With the exception of venom from Naja naja, all the tested venoms from unrelated families also showed cross-reactivity. This procedure is useful for detecting snake venom or its components in biological samples.
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213
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Saeed SA, Simjee RU, Gilani AH, Siddiqui S, Saleem R, Faizi S, Siddiqui B, Farnaz S. 8-Hydroxyquinoline and its derivatives: potential inhibitors of platelet aggregation. Biochem Soc Trans 1992; 20:357S. [PMID: 1487018 DOI: 10.1042/bst020357s] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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214
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Gilani AH, Shaheen F, Adil Q, Begum S, Siddiqui BS, Siddiqui S. Presence of arachidonic acid-like substance(s) in Thevitia neriifolia. Biochem Soc Trans 1992; 20:358S. [PMID: 1487019 DOI: 10.1042/bst020358s] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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215
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Abstract
Epidermoid cyst of the testicle is rare in children and only four previous cases have been reported. We add two cases and discuss their presentation and management. Both children presented with solid testicular masses, one of which was asymptomatic and the other was painful. Physical examination and ultrasound could not differentiate between a benign and malignant process. One child underwent radical orchiectomy and one child underwent local excision alone. Both are free of disease at follow-up.
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216
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Siddiqui S. Epidemiologic patterns and control strategies in typhoid fever. J PAK MED ASSOC 1991; 41:143-6. [PMID: 1895502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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217
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Ara I, Siddiqui BS, Faizi S, Siddiqui S. Tricyclic Diterpenes from the Stem Bark of Azadirachta indica. PLANTA MEDICA 1990; 56:84-6. [PMID: 17221373 DOI: 10.1055/s-2006-960891] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Two new diterpenoids, margosone and margosolone, have been isolated from the stem bark of AZADIRACHTA INDICA A. Juss (neem) and their structures established as 12,13-dihydroxy-14-isoporpylpodocarpa-8,11,13-trien-7-one and 13-hydroxy-12-methoxypodocarpa-8,11,13-trien-7-one, respectively, through chemical and spectroscopic studies.
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218
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Mujeeb SA, Siddiqui S, Khursheed T, Hashmi MR. Weakening of antigen D and development of anti-D in a patient with acute myeloid leukaemia. J PAK MED ASSOC 1989; 39:324-5. [PMID: 2517439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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219
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Siddiqui S, Siddiqui BS, Begum S, Hafeez F. Kanerocin: A New Triterpene from the Leaves of Nerium oleander. PLANTA MEDICA 1989; 55:292-3. [PMID: 17262420 DOI: 10.1055/s-2006-962009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
From the fresh, undried, and uncrushed leaves of NERIUM OLEANDER a new triterpenoid, kanerocin, has been isolated along with known ursolic and oleanolic acids and its structure established through chemical and spectroscopic methods as 3alpha-hydroxy-urs-18,20-dien-28-oic acid.
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Barrios N, Tebbi CK, Rotstein C, Siddiqui S, Humbert JR. Brainstem invasion by Aspergillus fumigatus in a child with leukemia. NEW YORK STATE JOURNAL OF MEDICINE 1988; 88:656-8. [PMID: 3068594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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221
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Siddiqui S, Mahmood T, Siddiqui BS, Faizi S. Non-terpenoidal constituents from Azadirachta indica. PLANTA MEDICA 1988; 54:457-9. [PMID: 17265315 DOI: 10.1055/s-2006-962500] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Studies on the acidic fraction of the fresh, uncrushed twigs of AZADIRACHTA INDICA JUSS (Meliaceae) (Neem) have resulted in the isolation and structure elucidation of one new and three unreported isocoumarins along with two unreported coumarins. The petroleum ether extract of the fresh leaves yielded a hydrocarbon fraction, the GC-MS of which led to the identification of eight saturated hydrocarbons. Fatty acid compositions of leaves, twigs, and fruits of neem have also been determined.
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Siddiqui S, Siddiqui BS, Hafeez F, Begum S. Oleanderoic Acid and Oleanderen from the Leaves of Nerium oleander. PLANTA MEDICA 1988; 54:232-4. [PMID: 17265258 DOI: 10.1055/s-2006-962413] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
A new labdane diterpene, oleanderoic acid and a new triterpene, oleanderen have been isolated from the fresh, undried and uncrushed leaves of NERIUM OLEANDER. Their structures have been established as 8alpha-methoxylabdan-18-oic acid, and 12-ursene, respectively, through chemical and spectral studies, including 2D-NMR (COSY-45, NOESY and 2D- J resolved) and (13)C-NMR data.
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223
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Ahmad SS, Haider SI, Siddiqui S. A One-Pot Synthesis of Sandwicoline and its Three Diastereoisomers from Related Alkaloids. SYNTHESIS-STUTTGART 1988. [DOI: 10.1055/s-1988-27613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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224
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Grant D, Siddiqui S, Graham J. Receptor-mediated endocytosis of enterokinase by rat liver. Preliminary characterisation of low-density endosomes. BIOCHIMICA ET BIOPHYSICA ACTA 1987; 930:346-58. [PMID: 2820502 DOI: 10.1016/0167-4889(87)90008-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The endocytosis of enterokinase by rat hepatocytes has been studied both in a perfused liver system and in the intact, anaesthetised animal. 10 min after administration of the enzyme, only 70% of the activity was cleared by the perfused liver, whereas clearance was total in the intact animal. In both cases, about 85% of the internalised enzyme co-purified with the smooth microsomes and virtually all (more than 90%) of the catalytic activity was latent and could only be detected in the presence of detergent. After 10 min, 22.5% of the activity remained with the sinusoidal plasma membrane in the case of the perfused liver, while for the intact animal this figure was only 10%, confirming the more efficient clearance of enterokinase in the intact animal. Further subcellular fractionation showed that in the anaesthetised animal 8% of the internalised enzyme was associated with a low-density Golgi-like endosomal compartment (prepared from the mitochondrial pellet), whereas the corresponding value for the perfused liver was only 2.5%. Enterokinase specific activity was also up to 50-times greater in the low-density endosomes prepared from the intact animal. A second low-density Golgi-like compartment (purified from the smooth microsomes) also contained latent enterokinase, which together with the endosomes derived from the mitochondria accounted for 20% of the total enterokinase internalised by the liver 10 min after its administration to the intact animal. The passage of enterokinase through these two low-density compartments was shown not to be synchronous with its passage through the peripheral (sinusoidal membrane) and internal endosomes (smooth microsomes). There were qualitative differences in marker enzymes and polypeptide composition between the mitochondria and microsome-derived low-density endosomes. The sub-fractionation of low-density fractions on shallow sucrose gradients revealed a complex enzyme and polypeptide heterogeneity both between and within fractions. There was an apparent density-dependent separation of enterokinase from galactosyltransferase and the asialoglycoprotein receptor which was coincident with marked changes in the polypeptide composition of the endosomal membranes, particularly in the 30-45 kDa range.
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Siddiqui S, Siddiqui BS, Hafeez F, Begum S. Isolation and Structure of Neriucoumaric and Isoneriucoumaric Acids from the Leaves of Nerium oleander. PLANTA MEDICA 1987; 53:424-7. [PMID: 17269060 DOI: 10.1055/s-2006-962763] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Two new coumaryloxy triterpenoids, neriucoumaric and isoneriucoumaric acids, have been isolated from fresh, undried and uncrushed leaves of NERIUM OLEANDER and their structures established as 3beta-hydroxy-2alpha-cis- P-coumaryloxy-urs-12-en-28-oic acid and 3beta-hydroxy-2alpha- TRANS- P-coumaryloxy-urs-12-en-28-oic acid respectively, through chemical and spectroscopic methods.
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226
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Gutierrez-Hartmann A, Siddiqui S, Loukin S. Selective transcription and DNase I protection of the rat prolactin gene by GH3 pituitary cell-free extracts. Proc Natl Acad Sci U S A 1987; 84:5211-5. [PMID: 3474648 PMCID: PMC298824 DOI: 10.1073/pnas.84.15.5211] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Prolactin (PRL) is a member of the growth hormone gene family that is specifically expressed in the lactotroph cells of the anterior pituitary. Whole cell extracts have been prepared from cultured GH3 rat pituitary tumor cells to study lactotroph-specific expression of the rat PRL (rPRL) gene in an in vitro transcription assay. The human alpha 1-globin and Rous sarcoma virus promoters efficiently initiate transcription in both HeLa and GH3 cell extracts, whereas the rPRL promoter containing 425 base pairs of 5' flanking DNA is active only in GH3 pituitary cell-free extracts. Transcription of the rPRL gene was reconstituted in HeLa cell extracts by the addition of GH3 cell extracts. DNase I digestion of the rPRL promoter reveals two protected regions centered at positions -55 (I) and -160 (III) that are GH3 cell-specific and rPRL promoter-selective. These "footprints" overlie a highly conserved 8-base-pair motif, CCTGATAATA. By contrast, footprint II at position -125 is common to both HeLa and GH3 cell extracts and overlies a 15-base-pair sequence found in all members of the growth hormone gene family. Thus, GH3 pituitary cell-free extracts selectively transcribe the rPRL gene and contain cell-specific factors that directly interact with the rPRL promoter. These studies provide useful assays to further identify, purify, and characterize pituitary-specific transcription factors and to address the biochemical mechanisms involved in rPRL gene expression.
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Siddiqui S, Ahmad SS, Haider SI. A New Alkaloid Ajmalimine from the Roots of Rauwolfia serpentina. PLANTA MEDICA 1987; 53:288-9. [PMID: 17269023 DOI: 10.1055/s-2006-962708] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
A new indole alkaloid ajmalimine has been isolated from the roots of RAUWOLFIA SERPENTINA collected in Thailand. Its structure, 21-(trimethoxybenzoyl)-ajmaline, was established by spectroscopic and chemical means.
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Siddiqui S, Begum S, Hafeez F, Siddiqui BS. Isolation and Structure of Neriumol and Nerifol from the Leaves of Nerium odorum. PLANTA MEDICA 1987; 53:47-9. [PMID: 17268959 DOI: 10.1055/s-2006-962616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
From the fresh, undried, uncrushed leaves of NERIUM ODORUM, two hydroxy acid methyl esters, neriumol and nerifol, have been isolated and their structures established as methyl (7 S,16)-dihydroxyhexadeca-8 Z-enoate and methyl (8,16)-dihydroxyhexadecanoate, through chemical and spectroscopic methods.
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Friedman HS, Vasavada BC, Malec AM, Hassan KK, Shah A, Siddiqui S. Cardiac function in alcohol-associated systemic hypertension. Am J Cardiol 1986; 57:227-31. [PMID: 3946213 DOI: 10.1016/0002-9149(86)90896-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The pathogenesis of alcohol cardiomyopathy is obscure. Because systemic hypertension is observed in one-third of alcoholics, the relation of this finding to left ventricular (LV) function was analyzed in 66 alcoholics (26 with a blood pressure of 160/95 mm Hg or higher) 4 to 5 days after alcohol withdrawal. Hypertensive alcoholics had a more abnormal ratio of preejection period/LV ejection time (PEP/ET) (0.398 +/- 0.01 vs 0.35 +/- 0.01, p less than 0.02) than normotensive alcoholics (matched normal 0.290 +/- 0.01). Hypertensive alcoholics (transitory hypertension) with blood pressures of 120/80 mm Hg or less at time of study also had more abnormal PEP/LVET than matched normotensive alcoholics (0.415 +/- 0.03 vs 0.331 +/- 0.01, p less than 0.05). In both hypertensive (77 +/- 6 dynes/cm2 X 10(3)) and normotensive alcoholics (67 +/- 4 dynes/cm2 X 10(3) LV stress was elevated (normal 46 +/- 3 dynes/cm2 X 10(3), both p less than 0.02). However, LV mass was not increased (hypertensive 96 +/- 4 g/m2; vs normotensive 100 +/- 4 g/m2; (normal 92 +/- 5 g/m2), resulting in a markedly increased stress to mass ratio (hypertensive 0.8 +/- 0.06; Normal 0.05 +/- 0.05, p less than 0.02). Hypertensive alcoholics also had LV "hyperfunction," with an increased stress/LV end-systolic volume ratio (1.7 +/- 0.1 vs 1.3 +/- 0.1 dynes/cm2 X 10(3)/ml, p less than 0.02). Thus, hypertensive alcoholics, even those with transitory hypertension, have more abnormal cardiac function than normotensive alcoholics. Presence of hypertension with hyperdynamic LV features may be a prelude to heart failure.
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Siddiqui S, Siddiqui BS, Faizi S. Studies in the Chemical Constituents of Azadirachta indica Part II: Isolation and Structure of the New Triterpenoid Azadirachtol. PLANTA MEDICA 1985; 51:478-80. [PMID: 17345262 DOI: 10.1055/s-2007-969567] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
A new triterpenoid named azadirachtol ( 1) has been isolated from the fruits of AZADIRACHTA INDICA Juss. (neem) of which the structure is reported on the basis of chemical and spectral data. Azadirachtol appears to be the first apo-tirucallol (apo-euphol) derivative possessing an eight carbons side-chain with an oxygenated ring system isolated from neem. Moreover, it is the first instance of the isolation of an 11-hydroxy triterpenoid from any of the various parts of neem.
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Malik A, Siddiqui S. Isolation of serpentine and tetraphylline from Rauwolfia vomitoria. PLANTA MEDICA 1983; 47:127-8. [PMID: 17405107 DOI: 10.1055/s-2007-969971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
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232
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Malik ZA, Siddiqui S. Hypotensive effect of freeze-dried garlic (Allium Sativum) sap in dog. J PAK MED ASSOC 1981; 31:12-3. [PMID: 6782270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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233
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Siddiqui S, Firat D, Olshin S. Phase II study of emetine (NSC-33669) in the treatment of solid tumors. CANCER CHEMOTHERAPY REPORTS 1973; 57:423-8. [PMID: 4586950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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234
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Olshin S, Siddiqui S, Firat D. Phase II study of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU; NSC-409962) in the treatment of bronchogenic carcinoma. CANCER CHEMOTHERAPY REPORTS 1972; 56:259-61. [PMID: 5043228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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235
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236
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Khan MA, Siddiqui S. Isolation and structure of raucaffrinoline--a new alkaloid from Rauwolfia caffra sonder. EXPERIENTIA 1972; 28:127-8. [PMID: 5020328 DOI: 10.1007/bf01935708] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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