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Cass QB, Tiritan ME, Calafatti SA, Matlin SA. ENANTIOSEPARATION ON AMYLOSE TRIS(3,5-DIMETHOXYPHENYL CARBAMATE): APPLICATION TO COMMERCIAL PHARMACEUTICAL CHIRAL DRUGS. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-100102077] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Morel CM, Acharya T, Broun D, Dangi A, Elias C, Ganguly NK, Gardner CA, Gupta RK, Haycock J, Heher AD, Hotez PJ, Kettler HE, Keusch GT, Krattiger AF, Kreutz FT, Lall S, Lee K, Mahoney R, Martinez-Palomo A, Mashelkar RA, Matlin SA, Mzimba M, Oehler J, Ridley RG, Senanayake P, Singer P, Yun M. Health Innovation Networks to Help Developing Countries Address Neglected Diseases. Science 2005; 309:401-4. [PMID: 16020723 DOI: 10.1126/science.1115538] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Gross inequities in disease burden between developed and developing countries are now the subject of intense global attention. Public and private donors have marshaled resources and created organizational structures to accelerate the development of new health products and to procure and distribute drugs and vaccines for the poor. Despite these encouraging efforts directed primarily from and funded by industrialized countries, sufficiency and sustainability remain enormous challenges because of the sheer magnitude of the problem. Here we highlight a complementary and increasingly important means to improve health equity: the growing ability of some developing countries to undertake health innovation.
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Norton R, Matlin SA. The role of health research in the prevention and control of road traffic injuries in South Asia. JCPSP-JOURNAL OF THE COLLEGE OF PHYSICIANS AND SURGEONS PAKISTAN 2005; 14:705-6. [PMID: 15610624 DOI: 12.2004/jcpsp.705706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Received: 10/06/2004] [Accepted: 10/06/2004] [Indexed: 11/13/2022]
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Cosentino MJ, Matlin SA. Pharmacological developments in male contraception. Expert Opin Investig Drugs 2005; 6:635-53. [PMID: 15989632 DOI: 10.1517/13543784.6.6.635] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
To date, the current methods of male contraception are limited to condoms, coitus interruptus and vasectomy, all of which are beset with difficulties. The condom is inconvenient, dulls sensation, and although somewhat effective against sexually transmitted disease, has an increased failure rate over time of usage. Coitus interruptus reduces the pleasurable aspects of intercourse and is plagued with a high failure rate. Vasectomy is virtually sterilisation. The current research into new forms of contraception is as diverse as the mechanisms controlling male fertility. The majority of effort has focused on antispermatogenic agents. Hormonal agents that suppress spermatogenesis appear nearest to final development and are primarily centred around various testosterone esters. These can be administered alone or in combination with progestogens. Another promising line of study centres on gonadotropin releasing hormone (GnRH) antagonism resulting in suppression of gonadotropins. Non-hormonal antispermatogenic agents include numerous phytochemicals, and testicular enzyme inhibitors. Post-testicular approaches to male contraception include agents that interfere with sperm metabolism, motility, maturation or transport. This review summarises recent clinical and animal studies on these compounds with emphasis on their mechanism of action, advantages and drawbacks.
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Matlin SA. Perspectives for the development of new contraceptives. SOCIAL BIOLOGY AND HUMAN AFFAIRS 2002; 49:43-57. [PMID: 12340738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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Cass QB, Bassi AL, Matlin SA. First direct resolution of gossypol enantiomers on a chiral high-performance liquid chromatography phase. Chirality 1999. [DOI: 10.1002/(sici)1520-636x(1999)11:1<46::aid-chir8>3.0.co;2-i] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Tiritan ME, Cass QB, Del Alamo A, Matlin SA, Grieb SJ. Preparative enantioseparation on polysaccharide phase using microporous silica as a support. Chirality 1998. [DOI: 10.1002/(sici)1520-636x(1998)10:7<573::aid-chir4>3.0.co;2-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Sharaf M, el-Ansari MA, Matlin SA, Saleh NA. Four flavonoid glycosides from Peganum harmala. PHYTOCHEMISTRY 1997; 44:533-536. [PMID: 9014375 DOI: 10.1016/s0031-9422(96)00531-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The aerial parts of Peganum harmala yielded four new flavonoids: acacetin 7-O-rhamnoside, 7-O-[6"-O-glucosyl-2"-O-(3'''-acetylrhamnosyl)glucoside and 7-O-(2'''-O-rhamnosyl-2"-O-glucosylglucoside), and the glycoflavone 2'''-O-rhamnosyl-2"-O-glucosylcytisoside.
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Cass QB, Degani AL, Tiritan ME, Matlin SA, Curran DP, Balog A. Enantiomeric resolution by HPLC of axial chiral amides using amylose tris[(S)-1-phenylethylcarbamate]. Chirality 1997; 9:109-12. [PMID: 9134693 DOI: 10.1002/(sici)1520-636x(1997)9:2<109::aid-chir6>3.0.co;2-c] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The enantiomeric resolution of a series of N-arylamides was examined on amylose tris[(S)-1-phenylethylcarbamate] coated onto aminopropylated 7 microns silica with 500 A diameter pores and on naked silica 5 microns particle size with 500 A diameter pores. The enantiomeric resolution obtained for this series was excellent on both columns. The enantioselectivity of cellulose and amylose tris(3,5-dimethylphenylcarbamate) coated onto APS-Hypersil (120 A pore size, 5 microns particle size) was also investigated for this series of compounds.
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Tarantal AF, Hendrickx AG, Matlin SA, Lasley BL, Gu QQ, Thomas CA, Vince PM, Van Look PF. Effects of two antiprogestins on early pregnancy in the long-tailed macaque (Macaca fascicularis). Contraception 1996; 54:107-15. [PMID: 8842588 DOI: 10.1016/0010-7824(96)00134-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The abortifacient effects of mifepristone and HRP 2000 were compared in gravid long-tailed macaques. Thirty-six animals were studied with treatment administered either by the oral (0.5 or 5.0 mg/kg; N = 5 per antiprogestin per dose) or intramuscular (i.m.) routes (0.5 mg/kg; N = 5 per antiprogestin) on gestational days (GD) 23-26; six vehicle controls were included. Blood samples were collected for assay of progesterone (P4) and each of the antiprogestins (pre-treatment, daily GD 23-28, every other day GD 30-40), and animals were monitored sonographically throughout gestation. Results of these studies indicated high rates of abortion with i.m. administration (3/5 mifepristone, 4/5 HRP 2000) and 5.0 mg/kg oral route (4/5, 2/5, respectively), with less effects noted at oral doses of 0.5 mg/kg (2/5, 0/5, respectively). No early abortions were observed in the control groups. Following daily i.m. treatment, peak levels of 8-16 ng/ml mifepristone were detected whereas 6-10 ng/ ml of HRP 2000 were noted (GD 26-27). No serum levels of mifepristone were detected following either of the oral doses whereas serum levels of 2-6 ng/ml HRP 2000 were noted with high dose oral administratation. Results of these studies suggest: (1) both antiprogestins are roughly comparable in terminating early pregnancy although HRP 2000 may be more efficacious when administered i.m. whereas mifepristone may be more effective when administered orally; (2) similar levels of biological activity are seen with the i.m. and high dose oral dosing regimens, with little or no activity with the oral low dose; and (3) infants resulting from surviving pregnancies were not affected by early gestation exposure.
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Cass QB, Bassi AL, Calafatti SA, Matlin SA, Tiritan ME, de Campos LMM. Carbohydrate carbamate coated onto microporous silica: Application to chiral analysis of commercial pharmaceutical drugs. Chirality 1996. [DOI: 10.1002/(sici)1520-636x(1996)8:1<143::aid-chir21>3.0.co;2-m] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Cass QB, Bassi AL, Matlin SA. Chiral discrimination by HPLC on aryl carbamate derivatives of chitin coated onto microporous aminopropyl silica. Chirality 1996. [DOI: 10.1002/(sici)1520-636x(1996)8:1<131::aid-chir19>3.0.co;2-o] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Malik NS, Matlin SA, Fried J, Pakyz RE, Consentino MJ. The contraceptive effects of etoprine on male mice and rats. JOURNAL OF ANDROLOGY 1995; 16:169-74. [PMID: 7559148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We had previously found that 2,4-diaminopyrimidines affected spermatogenesis, possibly through the inhibition of testicular dihydrofolate reductase (DHFR). The current study examined the effects of etoprine, a highly lipophilic 2,4-diaminopyrimidine that is also a potent DHFR inhibitor, on the fertility of male mice at various dosages (0.1-50 mg/kg/day) for 55 days and male rats at 5 mg/kg/day for 65 days. Two other substituted diaminopyrimidines were tested at dosages of 50 mg/kg/day for 55 days. Results of breeding trials along with assessment of various parameters indicative of male fertility were noted. We found that of the compounds tested, etoprine is a potent antifertility agent that causes complete infertility at doses of > or = 5 mg/kg/day in mice with a threshold of effectiveness occurring between 1 and 5 mg/kg/day. The antifertility action of etoprine may be related to its capacity to inhibit testicular DHFR and its high degree of lipophilicity.
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Matlin SA, Grieb SJ, Belenguer AM. Flash chiral chromatography using carbohydrate carbamate-coated silica. ACTA ACUST UNITED AC 1995. [DOI: 10.1039/c39950000301] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Liang XS, Rogers AJ, Webber CL, Ormsby TJ, Tiritan ME, Matlin SA, Benz CC. Developing gossypol derivatives with enhanced antitumor activity. Invest New Drugs 1995; 13:181-6. [PMID: 8729944 DOI: 10.1007/bf00873798] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Preclinical and clinical studies have pointed to the antitumor potential of the naturally occurring polyphenolic binaphthyl dialdehyde, gossypol, as well as its purified (-,+) enantiomers. To explore further the antitumor properties of this multifunctional agent, we synthesized several reactive derivatives including the (-,+) enantiomers of gossypolone and four different gossypol Schiff's bases (AR1, AR2, AR3, AR4). The biological activities of these new agents were screened by measuring their in vitro antiproliferative activity against malignant (MCF-7, MCF-7/adr) or immortalized (HBL-100) human breast epithelial cell lines. Racemic gossypolone showed relatively uniform antiproliferative activity against all of the breast epithelial cell lines with 3- to 5-fold less activity than (--)-gossypol against MCF-7 and MCF-7/adr cells. Of interest, the relative antitumor potency of purified gossypolone enantiomers was reverse that of gossypol enantiomers, since (+)-gossypolone showed up to 3-fold greater inhibition of MCF-7 culture growth than (--)-gossypolone. Of the Schiff's base derivatives only AR3 with its isopropyl amine substituent demonstrated cytotoxic activity comparable to that of (--)-gossypol; derivatives with ethyl, propyl, or butyl amine substituents (AR1, AR2, AR4) had little growth inhibitory activity at culture concentrations up to 25 microM. AR3 activity was greatest against HBL-100 and MCF-7 cells [MCF-7 IC50 values: AR3 = 0.9 microM, (--)-gossypol = 2.3 microM]; unlike (--)-gossypol, however, AR3 showed substantially reduced activity against the multidrug-resistant subline, MCF-7/adr. These structure-activity comparisons suggest that isolation of (-,+)-enantiomers of AR3 and additional chemical modifications including the synthesis of an isopropyl amine Schiff's base of gossypolone will likely yield a newer generation of gossypol analogues with enhanced anticancer potential.
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Grieb SJ, Matlin SA, Phillips JG, Belenguer AM, Ritchie HJ. Chiral HPLC with carbohydrate carbamates: Influence of support structure on enantioselectivity. Chirality 1994. [DOI: 10.1002/chir.530060213] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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46
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Matlin SA, Tiritan ME, Crawford AJ, Cass QB, Boyd DR. HPLC with carbohydrate carbamate chiral phases: Influence of chiral phase structure on enantioselectivity. Chirality 1994. [DOI: 10.1002/chir.530060214] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Matlin SA, Belenguer A, Stacey VE, Qian SZ, Xu Y, Zhang JW, Sanders JK, Amor SR, Pearce CM. Male antifertility compounds from Tripterygium wilfordii Hook f. Contraception 1993; 47:387-400. [PMID: 8508668 DOI: 10.1016/0010-7824(93)90036-7] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Extracts of the Chinese medicinal plant, Tripterygium wilfordii, cause reversible infertility in male animals. Sub-fractionation studies have now revealed that the plant extracts contain a number of compounds which are potent antifertility agents in male mammals, including the diterpenes triptolide and tripdiolide and an isomer of the latter. A triptolide, 12,13-chlorohydrin, which is a transformation product formed reversibly by interaction of triptolide with HCl, was also found to be active.
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Tarantal AF, Hendrickx AG, Matlin SA, Lasley BL, Gu QQ, Thomas CA, Vince PM, Van Look PF. Tamoxifen as an antifertility agent in the long-tailed macaque (Macaca fascicularis). Contraception 1993; 47:307-16. [PMID: 8462320 DOI: 10.1016/0010-7824(93)90047-b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The potential use of tamoxifen, a nonsteroidal antiestrogen, as an antifertility agent was studied in the long-tailed macaque (Macaca fascicularis). Twenty-six cycling females were bred, then treated with a single oral dose of tamoxifen (5 mg/kg) (N = 13) or vehicle (N = 13) on day 4 post-ovulation. Serum progesterone (P4) and tamoxifen concentrations were evaluated on post-ovulation days 4, 8, 12, 16, and 18. No effects of treatment were observed on P4 concentrations or on the fertility rate--pregnancy was achieved in 4/13 controls (31%) and 6/13 treated females (46%). Analysis for serum tamoxifen concentrations in samples collected during the fertility and a supplemental pharmacokinetic study (N = 3; single oral dose of 10 mg/kg; urine and serum evaluated) failed to reveal any detectable tamoxifen levels. It was concluded that (1) absorption of tamoxifen may be negligible under the described treatment regimens or (2) tamoxifen metabolism/clearance occurs at a rapid rate.
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González-Garza MT, Matlin SA, Mata-Cárdenas BD, Said-Fernández S. Differential effects of the (+)- and (-)-gossypol enantiomers upon Entamoeba histolytica axenic cultures. J Pharm Pharmacol 1993; 45:144-5. [PMID: 8095532 DOI: 10.1111/j.2042-7158.1993.tb03701.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The in-vitro anti-amoebic effects of (+/-)-, (+)-, (-)-gossypol and emetine were tested against axenic trophozoites from five Entamoeba histolytica strains. The (-)-isomer was more active than the racemate and the (+)-isomer. These results indicate that the gossypol anti-amoebic activity is mainly due to its content of (-)-gossypol in all strains tested.
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Matlin SA, Belenguer A, Hall PE. Progesterone-releasing vaginal rings for use in postpartum contraception. I. In vitro release rates of progesterone from core-loaded rings. Contraception 1992; 45:329-41. [PMID: 1516365 DOI: 10.1016/0010-7824(92)90055-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Vaginal rings of Dow Corning 382 Silastic polymer, having identical outside dimensions, were fabricated to contain cores of different diameters loaded with 25% w/w progesterone. Elution of rings was carried out in continuously flowing baths of isotonic saline at 37 degrees C and quantities of progesterone released in 24 h periods measured for up to 128 days. Release of the steroid was shown to be a membrane diffusion-controlled process, modified by the development of a gradually increasing zone of depletion at the core surface. Rings of a suitable core diameter were selected to give initial release of 5 mg/24 h progesterone and sterile batches of these rings, prepared for WHO-sponsored clinical studies in post-partum, lactating women, were shown to give highly consistent and reproducible rates of in vitro drug delivery. A comparison was made with the in vitro release rates of rings containing a homogeneous dispersion of progesterone.
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