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1.
International journal of dentistry ; 2009Nov 2008. ilustab
Artigo em Inglês | MedCarib | ID: med-17794

RESUMO

Objective. This in vitro study uses measurements of fracture resistance to compare maxillary premolars restored with the bonded amalgam technique using a new resin luting cement, glass ionomer, and resin-modified glass ionomer as the bonding agents. Materials. Eighty-five sound maxillary premolars were selected and randomly assigned to one of five test groups of 17 teeth each. One group of intact teeth served as the control. The remaining groups were prepared to a standard cavity form relative to the dimensions of the overall tooth and restored with amalgam alone or a bonded amalgam using one of three luting agents: RelyX Arc (a new resin luting cement), RelyX luting (a resin-modified glass ionomer), or Ketac-Cem æ (a glass ionomer) as the bonding agents. Each tooth was then subjected to compressive testing until catastrophic failure occurred. The mean loads at failure of each group were statistically compared using ANOVA with a post hoc Bonferroni test. Results. It was found that regardless of the luting cement used for the amalgam bonding technique, there was little effect on the fracture resistance of teeth. Conclusion. Cusp fracture resistance of premolars prepared with conservative MOD cavity preparations is not improved by using an amalgam-bonding technique compared to similar cavities restored with amalgam alone.


Assuntos
Humanos , Técnicas In Vitro , Dente Canino , Amálgama Dentário , Cimentos de Ionômeros de Vidro , Cimentos Dentários , Trinidad e Tobago
2.
West Indian Veterinary Journal ; 5(1): 16-18, November 2005. graf, tab
Artigo em Inglês | MedCarib | ID: med-17843

RESUMO

This paper describes the extraction of the Neem (Azadirachta indica) bark and the determination of any statistically significant ascaricidal activity in the extract. The hexane extract of a bark sample, after reconstitution in dimethlysufoxide, was used to perform a bioassay on tick (Boophilus microplus) specimens, which were collected from cattle that had not been exposed to any acaricide for six weeks preceding (tick) collection. The percentage mortality of Boophhilus microplus obtained post administration were 100% for the pyrethroid cypermethrin, 56% for Azadirachta indica bark extract, distilled water- 8% and dimethylsulfoxide-16%. These differences in results were statistically significant at p<0.001.


Assuntos
Técnicas In Vitro , Azadirachta , Infestações por Carrapato , Bioensaio , Trinidad e Tobago
3.
West Indian veterinary journal ; 5(1): 16-18, November 2005. graf, tab
Artigo em Inglês | MedCarib | ID: med-18171

RESUMO

This paper describes the extraction of the Neem (Azadirachta indica) bark and the determination of any statistically significant ascaricidal activity in the extract. The hexane extract of a bark sample, after reconstitution in dimethlysufoxide, was used to perform a bioassay on tick (Boophilus microplus) specimens, which were collected from cattle that had not been exposed to any acaricide for six weeks preceding (tick) collection. The percentage mortality of Boophhilus microplus obtained post administration were 100% for the pyrethroid cypermethrin, 56% for Azadirachta indica bark extract, distilled water- 8% and dimethylsulfoxide-16%. These differences in results were statistically significant at p<0.001.


Assuntos
Técnicas In Vitro , Azadirachta , Infestações por Carrapato , Bioensaio , Trinidad e Tobago
4.
Cpd dentistry ; 5(3): 90-94, 2004.
Artigo em Inglês | MedCarib | ID: med-17570

RESUMO

Purpose: The purpose of this study was to assess the shear bond strength of amalgam when bonded to dentine with various cements. Materials and Methods: Eighty human molars were divided into five groups and ground dentine surfaces treated, with one of five cements (Fuji I, Vitrebond, Rely X, Fuji II and Panavia F). Spherical amalgam (Tytin) was condensed onto the unset cement and shear bond strengths were measured after one week. Results: The mean shear bond strength of Panavia F (25.3 MPa) was significantly higher compared with Fuji I (16.8 MPa), Fuji II (10.3 MPa) and Vitrebond (5.1 MPa) however there was no significant difference with Rely X (19.0 MPa). Conclusion: The combination of a resin modified glass ionomer luting cement with a spherical alloy may enhance bonding of amalgam to dentine.


Assuntos
Humanos , Técnicas In Vitro , Amálgama Dentário/análise , Cimentos de Ionômeros de Vidro/análise , Cimentos de Ionômeros de Vidro , Resistência ao Cisalhamento
5.
West Indian med. j ; 50(suppl 7): 33, Dec. 2001.
Artigo em Inglês | MedCarib | ID: med-62

RESUMO

Long-term potentiation (LTP) is a molecular engram of memory. Previous work has demonstrated that LTP decreases the sensitivity of glutamate receptors in the rat hippocampus. Glutamate has beem implicated in the pathogenesis of hypoxic/ischaemic damage. We therefore tested the hypothesis that LTP could reduce the effects of LTP on hypoxia in the rat hippocampus. The effects of LTP on hypoxia were measured by the changes in the extracellular potentials recorded from the hippocampal slice. Hypoxia was induced by perfusing the slice with artificial cerebrospinal fluid that contained varying concentrations of oxygen. Each slice was initially exposed to the hypoxic medium for 1.5-3.0 minutes. This led to a decrease in the potentials, which recovered to control levels within 5 minutes. Repeat exposure to the same hypoxic medium for the same duration as the first, also caused a reduction in the potentials. There was no significant difference between the degree of reduction caused by the first or second exposure for all types of hypoxic media tested (p >0.05; paired t test). In some slices, LTP was induced after the first hypoxic exposure. LTP brought about an inhibition of the reduction in potentials caused by the second hypoxic insult; the differences in reducation in potentials were highly significant for all the hypoxic media used (p <0.01; paired t test). The neuroprotective effects of LTP were not prevented by cyclothiazide (an inhibitor of AMPA receptor desensitization) or NOS inhibitors (antagonists of intracellular nitric oxide production). These compounds have been shown to be effective in blocking the effects of LTP on the actions of exogenously applied AMPA and NMDA, respectively. The neuroprotective effects of LTP were similar to that of propentofylline, a known neuroprotective compound. We conclude that LTP causes an appreciable protection of the hippocampus slices to in-vitro models of acute hypoxia. There have been reports that there is a possible inverse relationship between educational attainment and the development of dementia and the results of our study may have a role to play in this relationship. (AU)


Assuntos
Ratos , Técnicas In Vitro , 21003 , Hipóxia/prevenção & controle , Potenciação de Longa Duração/efeitos dos fármacos , Receptores de Glutamato/efeitos dos fármacos , Receptores de AMPA/efeitos dos fármacos , Estudo de Avaliação
6.
West Indian med. j ; 50(Suppl 5): 29-30, Nov. 2001.
Artigo em Inglês | MedCarib | ID: med-145

RESUMO

OBJECTIVE: To develop an agglutination technique using Staphylococcal protein A (SpA) and Steptococcalprotein G (SpG) to detect human red blood cell antibodies. METHODS: Blood samples were obtained from the National Transfusion Service of Jamaica. SpA, SpG, and anti-IgG, -C3d were commercial preparations. SpA and ApG were incubated with sensitized human red blood cells (RBC) to assess their RBC agglutinating capacity. The Ouchterlony technique was used to determine binding between the bacterial antigens and the IgG in human serum. Polyethyleneglycol (PEG) was used as an agglutination enhancer. Agglutination techniques for a large number of samples were developed, using 96 percent well polystyrene microplates and a microscope for visualizing the agglutination techniques to detect human anti-RBC IgG was compared with the traditional Coombs' test. Sensitivity and specificity were determined. RESULTS: SpA and SpG did not appear to cause agglutination of the red cells sensitized in vivo and in vitro. However, no precipitation bands were formed between human serum and the supernatant obtained after reaction of the sensitized RBC with SpA and SpG (Ouchterlony technique). These results indicated that indeed there was binding of SpA and SpG with the sensitized cells since they were not available for binding with human serum. In additon, SpA and SpG agglutinated the sensitized red blood cells in the presence of the PEG. When compared to the Coombs' test, the following results were obtained with new techniques. For the direct method, sensitivity was 93.8 percent and 95.1 percent for SpA and SpG respectively (n= 81), and specificity was 91.4 percent and 93.5 percent for SpA and SpG, respectivley (n= 93). For the indirect method, sensitivity was 96.3 percent and 97.5 percent for SPA and SpG, respectively (n= 81) and its specificity was 100 percent for both proteins (n= 85). CONCLUSION: Agglutination techniques using SpA and SpG constitute alternative and feasible tests for the detection of human red blood cell antibodies. (AU)


Assuntos
Técnicas In Vitro , Humanos , Testes de Aglutinação/métodos , Antígenos de Grupos Sanguíneos/imunologia , Anticorpos Anti-Idiotípicos/imunologia , Proteína Estafilocócica A/sangue , Antígenos de Bactérias/imunologia , Imunoglobulina G/análise , Eritrócitos/imunologia
7.
West Indian med. j ; 50(Suppl 5): 29, Nov. 2001.
Artigo em Inglês | MedCarib | ID: med-147

RESUMO

OBJECTIVE: Several local plant extracts are used in folklore practice as abortifacients. The objectives was to determine the scientific basis, if any, for these claims. METHODS: Aqeous extracts were prepared from 6 plants collected from St.Thomas, Jamaica: Leonotis nepetifolia (LN), Mentha pulegium (MP), Phyllanthus amarus (PA), Stachytarpheta jamaicensis (SJ), Gliricidia sepium (GS) and Wedelia gracilis (WG). The extracts were tested for contractile activity on isolated mouse uteri maintained in de Jalons solution. The effects of indomethacin and atropine on the contractions were used to indicate the possible mechanism of action. RESULTS: Three plant extracts (LN, MP and PA) produced dose-dependent contractions of the non-pregnant and pregnant mouse uteri. No contractions were observed with the other three extracts (SJ, GS, and WG). The contractions produced by MP were significantly reduced by indomethacin (p<0.05) but not by atropine. Contractions produced by LN and MP were blocked by either drug. Pregnant mice given LN litterd with live offspring within 24 hours. CONCLUSIONS: Of the 6 plants evaluated, 3 contracted the uterus in vitro but only one (LN) had a significant action in vivo. The contractile effect of MP may possibly be mediated via prostaglandins. However, this plant extract showed significant toxicity in vivo. (AU)


Assuntos
Camundongos , Técnicas In Vitro , Gravidez , 21003 , Feminino , Extratos Vegetais/toxicidade , Medicina Tradicional , Abortivos/uso terapêutico , Folclore , Estudo de Avaliação , Jamaica/etnologia
8.
West Indian med. j ; 50(3): 227-9, Sept. 2001. ilus
Artigo em Inglês | MedCarib | ID: med-279

RESUMO

Ovarian hyperstimulation is a recognized complication of ovulation induction with gonadotrophins. The syndrome is becoming more common as the number of women undergoing in-vitro fertilization increases. It is rarely seen in conjunction with clomiphene citrate usage. This case report is of moderate to severe ovarian hyperstimulation in a patient who was treated with clomiphene citrate because of infertility secondary to anovulation. She presented with amenorrhoea for five weeks, lower abdominal pain and a positive urinary human chronic gonadotrophin (hCG) test. Pelvic ultrasonography was suggestive of a possible ectopic pregnancy with a different diagnosis of a ruptured ovarian cyst. Diagnostic laparoscopy was done followed by laparotomy. Oophorectomy was performed because the ovary was thought to be complex with solid areas. However, conservative management with advance of laparotomy is the recommendation in confirmed cases of ovarian hyperstimulation but this requires a high level of suspicion in patients who have ovulation induction. (AU)


Assuntos
Adulto , Técnicas In Vitro , Relatos de Casos , Feminino , Humanos , Síndrome de Hiperestimulação Ovariana/induzido quimicamente , Clomifeno/efeitos adversos , Fármacos para a Fertilidade Feminina/efeitos adversos , Indução da Ovulação/efeitos adversos , Síndrome de Hiperestimulação Ovariana/diagnóstico , Síndrome de Hiperestimulação Ovariana/cirurgia
9.
West Indian med. j ; 50(3): 189-93, Sept. 2001. ilus, tab
Artigo em Inglês | MedCarib | ID: med-304

RESUMO

Homemade spacer devices are commonly used by children with asthma to improve aerosol deposition from pressurized metered dose inhalers (pMDI); however, the efficacy and efficiency of these devices are not fully characterized. We determined the quality of fine particle fraction (<4.7 um) and ultrafine particle fraction (<3.3 um) of three bottles (from 280 ml to 500 ml) commonly used as spacers in Trinidad and Tobago and compared their performance to the commercially available valved holding chamber (OpT) and pMDI. These data were obtained in vitro using a cascade impactor. All 3 bottles and OpT were similar (p>0.05) in reducing the amount of albuterol emitted as large particles (>4.7 um) to less than 10 ug. The diffreent sized bottles (from 280 ml to 500 ml) produced identical quantities of albuterol in the fine particle and ultrafine particle ranges (p>0.05). All of the sample bottle spacers emitted a higher amount (p<0.002) of fine and ultrafine particles than the OpT and pMDI alone. The OpT resulted in a significantly higher fraction of fine particles (p<0.05) and greater quantity of drug (<0.05) in the ultrafine range as compared to MDI only. The sizes of particles obtained from the bottle spacers are those that have a high probability of reaching the lower airway; however, the clinical relevance of these findings remains to be determined. (AU)


Assuntos
Humanos , Técnicas In Vitro , Estudo Comparativo , Nebulizadores e Vaporizadores/normas , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/normas , Trinidad e Tobago , Asma/tratamento farmacológico , Tamanho da Partícula , Plásticos
10.
West Indian med. j ; 50(2): 105-8, Jun. 2001.
Artigo em Inglês | MedCarib | ID: med-351

RESUMO

The tetracyclines are a group of broad-spectrum antimicrobial agents. The first of these compounds, chlortetracycline was isolated from Streptomyces aureofaciens by Benjamin Duggar and introduced into the market in 1948. In 1952, tetracycline was derived semisynthetically from chlortetracycline by removal of its chlorine atom by catalytic hydrogenation. Methacycline, doxycycline and minocycline are all semi-synthetic derivatives. The tetracyclines are closely congeneric derivatives of polycyclic napthacenecarboxamide. The tetracyclines posses a wide range of antimicrobial activity against gram-positive and gram-negative bacteria. In vitro, these drugs are primarily bacteriostatic. Tetracycline have been used extensively as antimicrobial, chemically modified non-antimicrobial properties by Golub. The tetracyclines and their non-antimicrobial, chemically modified analogues have properties that appear to modulate host response by inhibiting the activity of the matrix metalloproteinases that cause collagen destruction. They also inhibit osteoclast function, stimulate osteoblastic bone formation, and regulate angiogenesis.(Au)


Assuntos
Técnicas In Vitro , Humanos , Tetraciclinas/farmacologia , Resistência Microbiana a Medicamentos , Doenças Periodontais/tratamento farmacológico , Metaloproteinase 3 da Matriz/antagonistas & inibidores , /farmacologia , Neovascularização Fisiológica , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Periodontite/tratamento farmacológico
11.
West Indian med. j ; 50(suppl. 1): 55, Mar. 1-4, 2001.
Artigo em Inglês | MedCarib | ID: med-420

RESUMO

The nitric oxide donor S-nitrosoglutathione (GSNO) has been used to prevent platelet activation in patients with severe pre-eclampsia. The study assesses the chronic administration of GSNO on glucose metabolism in the dog animal model. GSNO (10 mg/kg) was administered intravenously for 14 days and the blood glucose concentration was determined by the glucose oxidase method. Oral glucose tolerance tests revealed an impaired glucose tolerance in the GSNO-treated dogs as reflected by elevated postprandial blood glucose concentrations at the 1.0 hour to 2.5 hour time interval (p < 0.05). The elevated blood glucose concentration was associated with a statistically significant decrease in plasma insulin concentration. The plasma insulin concentration at 1.0 hour in captopril-treated controls was 41.00 uIU/ml compared with 27.33 uIU/ml in GSNO-treated dogs (p < 0.05). In contrast, the plasma glucagon concentration was enhanced by the chronic adminstration of GSNO, as confirmed by a concentration of 75.00 ñ 6.06 pg/ml in GSNO-treated dogs compared with 49.50 ñ 4.64 pg/ml in captopril-treated controls at the 1.0 hour time interval. Linear regression analysis of the data revealed a highly significant and positive correlation between the blood glucose concentration and the plasma glucagon concentration (r = 0.739, p < 0.01). Similarly, a positive correlation existed between the blood glucose concentration and the plasma insulin concentration (r = 0.513, p = 0.307). We conclude that chronic in vivo adminstration of GSNO impairs the parameters of carbohydrate metabolism. Patients who are on protracted treatment with GSNO could be risk for the development of diabetes mellitus.(Au)


Assuntos
Cães , 21003 , Técnicas In Vitro , Ativação Plaquetária , Doadores de Óxido Nítrico/administração & dosagem , Glucose/metabolismo , Teste de Tolerância a Glucose , Cães/metabolismo , Avaliação de Medicamentos , Carboidratos/metabolismo
12.
West Indian med. j ; 49(suppl.4): 17-8, Nov. 9, 2000.
Artigo em Inglês | MedCarib | ID: med-387

RESUMO

INTRODUCTION: At the Fertility Management Unit, an assisted reproduction technology service was established in June 2000. Twenty-eight couples were enrolled for treatment, which was carried out in collaboration with staff of the Midland Fertility Service, United Kingdom, and a local team of doctors, nurses and embryologist. The main Pre-treatment diagnoses were tubal factors in eight (28.5 percent) women and oligospermia in eight males (28.5 percent). The mean age of the women was 34.1 years (range 27 to 41 years). METHODS: All patients under the "long protacol" with down regulations of the hypothalamo-pituitary-ovarian axis, using subcutaneous injections of the gonadotrophin releasing hormone agonist (Buserelin), followed by stimulation with the human menopausal gonadotrophin (Pergonal), for ovulation induction. Monitoring of the response was by use of transvaginal ultrasound at the end of down regulation, day 5 of stimulation and from day 9 until the follicles were determined to be ready for retrieval. Oestradiol levels were measured and human chorionic gonadotrophin (Profasi) was given to mature the oocytes. Oocyte recovery was by transvaginal ultrasound-guided needle aspiration of the follicles 35 hours later. Two days after egg recovery and fertilisation, embryos were transferred back to the patient. There were 24 transfers of 1, 2 or 3 embryos. Fertilised embryos not transferred were cryopreserved at -70 degree celcius. Ten women received human chorionic gonadotrophin (HCG) on the day of transfer and 2, 4 and 6 days later, for luteal phase support, and 24 women received progesterone pessaries. RESULTS: All women responded and came to oocyte recovery. There were 3 cases of ovarian hyperstimulation syndrome (OHSS), one severe and 2 mild. Ten couples had intracytoplasmic sperm injection (ICSI) as planned. Two percutaneous epididymal sperm aspirations were necessary due to aspermia, so these had ICSI as well. Standard in vitro firtilzation procedures were used in 16 cases. Twenty-five patients (89.3 percent) had fertilised oocytes. Three couples had no fertilisations. The patient with severe OHSS had numerous fertilisations but no embryos were transferred to the patient. Five patients (20.8 percent) had "chemical" pregnancies. Three pregnancies have continued, 2 twins and one singleton. The pregnancy rate for viable pregnancies is therefore 12.5 percent. CONCLUSION: In vitro fertilization had been successfully achieved (Au)


Assuntos
Adulto , Feminino , Humanos , Masculino , Técnicas In Vitro , Fertilização In Vitro/métodos , Síndrome de Hiperestimulação Ovariana/complicações , Jamaica , Vagina/diagnóstico por imagem
13.
West Indian med. j ; 48(4): 198-9, Dec. 1999. gra
Artigo em Inglês | MedCarib | ID: med-1573

RESUMO

A non proteinaceous extract of Bromelia pinguin fruit was examined for activity on the rat uterus in vivo and in vitro. The in vivo experiments involved pregnant rats given the extract intraperitoneally. These rats did not abort nor were any foetal deformities observed. The extract inhibited spontaneous activity of the pregnant rat uterus in vitro. The extract of Bromelia pinguin fruit may have some utero-active compound which inhibits uterine motility.(AU)


Assuntos
Ratos , Técnicas In Vitro , 21003 , Gravidez , Feminino , Contração Uterina/efeitos dos fármacos , Extratos Vegetais , Abortivos , Plantas Medicinais , Prenhez/efeitos dos fármacos , Ratos Wistar
14.
Placenta ; 19(4): 321-31, May 1998.
Artigo em Inglês | MedCarib | ID: med-1765

RESUMO

The fetus has a substantial demand for glycine, which is satisfied in part by placental formation. The ability to form glycine through the activity of alanine: gloxylate aminotransferase enzyme was measured in placentae from normal term human pregnancies and placentae from rats at day 20 of gestation. There was no detectable enzyme activity in either human or rat placentae, although activity was measured in rat liver. It is concluded that in the placenta glycine is only formed from serine through the activity of serine hydroxymethyl transferase enzyme, which uses folate as a cofactor, because there is no other known metabolic pathways for endogenous glycine production.(AU)


Assuntos
Ratos , Técnicas In Vitro , 21003 , Feminino , Humanos , Recém-Nascido , Gravidez , Glicina/biossíntese , Placenta/metabolismo , Transaminases/metabolismo , Fígado/enzimologia , Troca Materno-Fetal , Placenta/enzimologia , Ácido Pirrolidonocarboxílico/urina
15.
Lupus ; 4(2): 138-41, Apr. 1995.
Artigo em Inglês | MedCarib | ID: med-4703

RESUMO

A retrovirus human T cell lymphotropic virus type I (HTLV-I), is an essential but not a sufficient aetiological factor for tropical spastic paraparesis (TSP). Because some TSP patients have biological false positive tests for trepomemal infections (BFP-STS), we used EISA to study BFP-STS and anticardiolipin antibodies in 42 Jamaican TSP patients. The data indicate that in TSP anticardiolipin antibodies accur in about 26 percent of patients, are associated with biological false positive treponemal serology, are relatively restricted to the IgA isotype and may be induced by HTLV-I or other non-treponemal infections. (Au)


Assuntos
Adulto , Humanos , Feminino , Masculino , Técnicas In Vitro , Imunoglobulina A , Anticorpos Antifosfolipídeos , Paraparesia Espástica Tropical , Vírus Linfotrópico T Tipo 1 Humano , Retroviridae , Manifestações Neurológicas , Vírus Linfotrópico T Tipo 1 Humano/patogenicidade , Infecções por Treponema/epidemiologia , Ensaio de Imunoadsorção Enzimática , Sífilis/diagnóstico , Região do Caribe
16.
British journal of obstetrics and gynaecology ; 97(5): 455-456, May 1990. ilus
Artigo em Inglês | MedCarib | ID: med-17134

RESUMO

A modified bivalve vaginal speculum has been designed which acts to prevent loss of semen when the instrument is removed during DI treatment. It would be valuable at this stage to assess its effect on success rates by means of a long-term study (AU)


Assuntos
Humanos , Feminino , Técnicas In Vitro , Inseminação Artificial/instrumentação , Inseminação Artificial , Obstetrícia , Fertilização , Técnicas de Diagnóstico Obstétrico e Ginecológico
17.
Eur J Clin Nutr ; 44(5): 363-9, May. 1990.
Artigo em Inglês | MedCarib | ID: med-13163

RESUMO

Red cells in oedematous malnutrition (kwashiorkor) have an increased sodium content, 'leakiness' to sodium and enhanced sodium pumping. In non-oedematous malnutrition (marasmus) there is a reduction in the sodium pump activity. The explanation has hitherto been unknown but the glutathione content of red cells is low in kwashiorkor and normal in marasmus. We artifically lowered the glutathione content of normal red cells to values characteristic of mild oedematous malnutrition, using the enzyme inhibitors bischloronitrosourea (BCNU) and buthionine sulfoximine (BSOX). After preincubation, the cells were washed to remove the inhibitors and oxidized glutathione. Cellular content of sodium and potassium, and 86Rb influx were then measured. The reduction in glutathione reproduce the abnormalities of sodium content and flux observed in kwashiorkor. We suggest that oxidant stress in kwashiorkor, by reducing cellular glutathione, may affect cell membrane electrolyte transport. This may act through alterations in membrane sulfhydryl groups. Glutathione depletion may therefore play an important role in the clinical picture and natural history of oedematous malnutrition and may have relevance to other conditions where oxidant stress occurs. (AU)


Assuntos
Humanos , Adulto , Masculino , Técnicas In Vitro , Eritrócitos/enzimologia , Glutationa/metabolismo , Kwashiorkor/metabolismo , Sódio/metabolismo , Antimetabólitos/farmacologia , Carmustina/farmacologia , Membrana Eritrocítica/metabolismo , Eritrócitos/efeitos dos fármacos , Glutationa/deficiência , Kwashiorkor/induzido quimicamente , Metionina Sulfoximina/análogos & derivados , Metionina Sulfoximina/farmacologia , Desnutrição Proteico-Calórica/metabolismo , Canais de Sódio/metabolismo , Kwashiorkor/sangue , Desnutrição Proteico-Calórica/sangue
18.
West Indian med. j ; 39(Suppl. 1): 56-7, Apr. 1990.
Artigo em Inglês | MedCarib | ID: med-5257

RESUMO

There are still uncertainties about the origin of the fatty acids (FA) deposited in the foetus, notably the percentage derived from the maternal circulation. This study describes a method to determine the amount of FA synthesized de novo in the foetus and the amount derived from the maternal circulation. Autopsy samples of subcutaeneous adipose tissue were obtained from 42 black foetuses and newborn infants. Samples of similar tissue were obtained from 50 pregnant women and 13 non-pregnant black women during surgery. FA analysis was done by gas chromatography. The accretion rate of FA in foetal adipose tissue was calculated by linear regression analysis of the FA data obtained from foetal/infant samples from the 22nd to 43rd week of gestation. The rate of foetal FA synthesized de novo in adipose tissue was calculated as the difference between the total foetal FA accretion rate and an estimate of the maternally derived FA. The latter was estimated from the values for accretion rates of saturated FA (SAFA), mono-unsaturated FA (MUFA), and polyunsaturated FA (PUFA) and total FA in foetal tissue, and the SAFA, MUFA and PUFA composition of adipose tissue in women (Table). Results show that of the total FA increment in foetal adipose tissue (22.7mg/g wet wt./week), 86.6 per cent was synthesized de novo by the foetus and the rest (13.2 per cent) was maternally derived (AU)


Assuntos
Humanos , Feminino , Gravidez , Recém-Nascido , Técnicas In Vitro , Desenvolvimento Embrionário e Fetal , Ácidos Graxos/metabolismo , Tecido Adiposo/embriologia , Proteínas Fetais , Troca Materno-Fetal
19.
New Haven, Ct; s.n; 1990. 65 p. ilus, maps, tab.
Tese em Inglês | MedCarib | ID: med-41

RESUMO

Endemic tropical spastic paraparesis/HTLV-I associated myelopathy (TSP/HAM) is a slowly progressive chronic neurological disorder that is manifested clinically by spastic paraperesis frequently in association with bowel and bladder dysfunction. It is one of the most common chronic neurologic disorders in many endemic foci around the world. Human T-lymphotropic virus type-1 (HTVL-I) has been etiologically associated with TSP/HAM based primarily on the high prevalence of antibodies to HTLV-I in the serum and CSF of affected patients. We report here the isolation of HTLV-I from peripheral blood lymphocytes and cerebrospinal fluid derived mononuclear cells of TSP/HAM patients by stimulation with interleukin-2 and cocultivation with umbilical cord blood mononuclear cells. Established cell lines contained HTLV-I antigen as demonstrated by immunoflourescence and cell-associated virus particles as observed by electron microscopy; low level reverse transcriptase activity was detected in cultures expressing viral antigens. Virus infected cultures were transformed in vitro as determined by their loss of contact inhibition and their continuous growth in the absence of exogenous IL-2. Of particular significance was our location of HTLV-I from three family members with TSP/HAM of varying duration and clinical severity. This study resulted in the first isolation of virus from a cluster of TSP/HAM patients within the same family, the first isolation of virus from a childhood case of TSP/HAM, and the first in vitro transformed HTLV-I infected cells from TSP/HAM patients. In addition, the methodology applied in this investigation subsequently has been used to consistently isolate virus from HTLV-I infected persons from widely separated geographic locations. This work supports a causative role for HTLV-I in the pathogenesis of TSP/HAM and helps to extend the spectrum of disease that may result from HTLV-I infection. (AU)


Assuntos
Adulto , Feminino , Humanos , Masculino , Adolescente , Relatos de Casos , Técnicas In Vitro , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Paraparesia Espástica Tropical , Infecções por HTLV-I/etiologia , Paraparesia Espástica Tropical/etiologia , Jamaica/epidemiologia , Colômbia/epidemiologia
20.
Leiden; s.n; 1989. 167 p. ilus, tab, gra.
Tese em Inglês | MedCarib | ID: med-2232

RESUMO

Describes a comparative analysis of RNA coliphages with special emphasis on regulatory and structural features. Phylogenetic phage sequence comparison reveals kinship between different phages and facilitates deduction of their secondary structure. Complete sequences from phage fr and partial sequences from group I phages M12, R17 and f2 were determined. The nucleotide sequence from a serological intermediate JP34 was partially elucidated, Only the fr sequence proved suitable for comparison with MS2 (similarity 77 per cent). A "core" structure (3' terminal region) of phage RNA proposed a certain structural resemblance with tRNA. Comparison of the MS2 and fr nucleotide sequences revealed absence of an AUG initiator codon for the fr lysis (L) gene. However, 4 codons further downstream there is a UUG codon which proved to be the start codon for the fr lysis gene. This UUG start codon proved crucial for L-gene regulation. It is suggested that terminated but not released ribosomes mediate the L-gene activation. A general eubacterial scanning model is proposed. It seems that ribosomes can scan the mRNA in both directions and reinitiate at the first encountered restart site. This eubacterial scanning model parallels the eukaryotic translation initiation mechanism


Assuntos
Resumo em Inglês , Técnicas In Vitro , RNA , Colífagos/ultraestrutura , Fagos RNA/genética , Nucleotídeos/diagnóstico , Sequência de Bases , Códon de Iniciação , Biossíntese de Proteínas
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