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1.
Transpl Infect Dis ; 14(4): 434-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22188555

RESUMO

Penicillium marneffei is a thermally dimorphic fungus that causes severe human immunodeficiency virus-related opportunistic infection in endemic areas of Southeast Asia and has rarely been reported in solid organ transplant (SOT) recipients. We report here the case of an Australian renal transplant patient who presented with disseminated P. marneffei infection shortly after a 10-day holiday to Vietnam, and review all previously published cases of penicilliosis associated with renal transplantation. This is the first reported case, to our knowledge, of P. marneffei infection in an SOT recipient acquired during travel to an endemic country, and highlights the importance of an accurate travel history when opportunistic infection is suspected, as well as giving appropriate health advice to transplant patients who travel.


Assuntos
Transplante de Rim/efeitos adversos , Micoses/diagnóstico , Penicillium/isolamento & purificação , Viagem , Idoso , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Austrália , Humanos , Hospedeiro Imunocomprometido , Itraconazol/uso terapêutico , Masculino , Micoses/tratamento farmacológico , Micoses/microbiologia , Penicillium/classificação , Resultado do Tratamento , Vietnã
2.
AIDS ; 11(10): 1249-54, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9256943

RESUMO

OBJECTIVE: The potential role of antiretroviral treatment on the infectiousness of HIV-1-infected men was examined by studying the effect of antiviral treatment on the shedding of HIV-1 in semen. METHODS: Forty-four patients enrolled in various treatment protocols were asked to donate a semen sample before they began a new antiviral treatment and at a follow-up visit after 6 to 15 weeks of treatment. Since most patients were on blinded protocols, patients were stratified by response of blood viral load. The effect of each patient's treatment was classified as good (n = 24), fair (n = 8) and marginal (n = 13) by measurement of the HIV RNA reduction in blood plasma (> 1.0 log10; 0.5-1.0 log10 and < 0.5 log10 HIV RNA copies/ml reduction, respectively). The effect of treatment on shedding of HIV-1 in semen was documented by the reduction of HIV RNA concentration in seminal plasma and by quantitative HIV-1 seminal cell culture. RESULTS: Overall, antiviral treatment resulted in a significant fall in the viral load in semen (RNA and culture) that paralleled the reduction of viral load in blood. More pronounced reductions of HIV RNA in semen were observed as the effectiveness of treatment on blood HIV RNA levels increased (median drop from baseline 0, 0.3 log10 and 0.8 log10 RNA copies/ml in patients with marginal, fair and good treatment effect, respectively). Thirteen patients lost detectable HIV RNA in blood on treatment and all of these had undetectable levels of HIV-1 in semen by culture and RNA analysis at follow-up. In 19 of the 31 patients (62%) who still had HIV RNA in their blood during treatment, semen HIV levels were below detection in semen at follow-up. CONCLUSIONS: Treatment-induced changes of HIV RNA concentration in blood are generally associated with a corresponding change in seminal HIV RNA: If confirmed in larger studies, potent antiretroviral therapy might reduce the spread of HIV-1.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1/isolamento & purificação , Sêmen/virologia , Infecções por HIV/sangue , Infecções por HIV/transmissão , Humanos , Masculino , RNA Viral/sangue , Estatísticas não Paramétricas , Cultura de Vírus
3.
AIDS ; 13(4): 487-94, 1999 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-10197377

RESUMO

OBJECTIVES: This study was undertaken to determine the relative effect of malaria infection on HIV concentration in blood plasma, and prospectively to monitor viral concentrations after antimalarial therapy. DESIGN: A prospective, double cohort study was designed to compare the blood HIV-1 RNA concentrations of HIV-positive individuals with and without acute malaria illness. Subjects were followed for 4 weeks after successful malaria therapy, or for 4 weeks from enrollment (controls). METHODS: Malawian adults with symptomatic Plasmodium falciparum parasitemia (malaria group) and asymptomatic, aparasitemic blood donors (control group) were tested for HIV-1 antibodies to identify appropriate study groups. The malaria group received antimalarial chemotherapy only and were followed with sequential blood films. In both groups, blood plasma HIV-1 RNA viral concentrations were determined at enrollment and again at 1, 2 and 4 weeks. RESULTS: Forty-seven malaria patients and 42 blood donors were enrolled. At enrollment blood plasma HIV-1 RNA concentrations were approximately sevenfold higher in patients with malaria than in blood donors (medians 15.1 x 10(4) and 2.24 x 10(4) copies/ml, respectively, P = 0.0001). No significant changes in median HIV-1 concentrations occurred in the 21 blood donors followed to week 4 (P = 0.68). In the 27 subjects successfully treated for malaria who were followed to week 4, a reduction in plasma HIV-1 RNA was observed from a median of 19.1 x 10(4) RNA copies/ml at enrollment, to 12.0 x 10(4) copies/ml at week 4, (P = 0.02). Plasma HIV-1 concentrations remained higher in malaria patients than controls (median 12.0 x 10(4) compared with 4.17 x 10(4) copies/ml, P = 0.086). CONCLUSIONS: HIV-1 blood viral burden is higher in patients with P. falciparum malaria than in controls and this viral burden can, in some patients, be partly reduced with antimalarial therapy.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/virologia , HIV-1 , Malária Falciparum/virologia , Carga Viral , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Adulto , Animais , Feminino , HIV-1/genética , Humanos , Malária Falciparum/tratamento farmacológico , Masculino , Estudos Prospectivos , RNA Viral/sangue
4.
J Clin Endocrinol Metab ; 80(9): 2761-7, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7673421

RESUMO

Disturbances in calcium metabolism in acute renal failure (ARF) remain incompletely understood. Most data are from patients with rhabdomyolysis. As renal impairment commonly accompanies severe malaria in the absence of rhabdomyolysis, falciparum malaria provides an alternative model of mineral homoeostasis in ARF. We studied 25 Vietnamese subjects, aged 18-63 yr, with severe malaria and 10 controls. Fourteen patients had a serum creatinine level of 250 mumol/L or less during treatment (group 1), five developed ARF but were not dialyzed (group 2a), and six required dialysis (group 2b). Group 1 patients presented with mild hypocalcemia (mean +/- SD serum ionized calcium, 1.18 +/- 0.05 vs. 1.23 +/- 0.02 mmol/L in controls; P = 0.01) that persisted until discharge in the presence of normal serum phosphate, PTH, and vitamin D metabolite levels. Group 2 patients were more hypocalcemic on admission (1.10 +/- 0.08 mmol/L; P < 0.0001 vs. controls), especially those in group 2b whose serum ionized calcium fell to 0.88 +/- 0.13 mmol/L when renal dysfunction was maximal. In group 2 patients, the admission serum PTH level was raised (5.4 +/- 3.8 vs. 2.7 +/- 0.9 pmol/L in controls; P < 0.02) and changed reciprocally with calcemia. Significant rises in serum phosphate occurred only in group 2b patients who had depressed serum free 1,25-dihydroxyvitamin D levels throughout. Hypercalcemia did not accompany the diuretic phase of ARF. These data suggest that parathyroid gland dysfunction is a cause of hypocalcemia in severe malaria without ARF, as seen in group 1 patients; in patients with ARF, the effect of the combination of phosphate retention and altered vitamin D metabolism on skeletal PTH sensitivity is of prime significance.


Assuntos
Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Homeostase , Malária Falciparum/complicações , Minerais/metabolismo , Injúria Renal Aguda/fisiopatologia , Adolescente , Adulto , Cálcio/sangue , Creatina Quinase/sangue , Feminino , Hemoglobinas/análise , Humanos , Rim/fisiopatologia , Fígado/fisiopatologia , Masculino , Pessoa de Meia-Idade , Mioglobinúria/urina , Hormônio Paratireóideo/sangue , Fosfatos/sangue , Vitamina D/metabolismo
5.
J Clin Endocrinol Metab ; 82(9): 3029-33, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9284738

RESUMO

Patients with malaria can have features of adrenal insufficiency. Because of the pathophysiological and clinical implications of an Addisonian state, the hypothalamic-pituitary-adrenocortical axis was assessed in nine Vietnamese adults with complicated malaria. A CRH test was performed on admission (in convalescence in five cases) and in six healthy controls. Basal plasma ACTH concentrations in the patients and controls were similar [median (range): 2.9 (0.2-9.7) vs. 3.5 (1.9-13.4) pmol/L, respectively; P > 0.1]. Serum cortisol levels were greater in the patients [882 (294-1682) vs. 190 (110-676) nmol/L; P < 0.01], but three (33%) had values within the control range. Basal serum corticosteroid-binding globulin concentrations were similar in patients and controls (P = 0.23). The post-CRH rise in plasma ACTH was attenuated in the patients [peak: 6.1 (0.9-23.2) vs. 14.5 (6.2-21.5) pmol/L in controls; P < 0.05]; basal and peak plasma ACTH correlated with plasma interleukin-6 in this group (rs > or = 0.60; P < or = 0.04). Serum cortisol responses to CRH were depressed in acute illness [peak 990 (394-1, 805) nmol/L or 10 (0-50%) above baseline vs. 500 (429-703) nmol/L or 160 (10-380%) in controls; P < 0.05]. The median estimated serum cortisol t1/2 was 4.6 h in the patients and 1.6 h in the controls. These data suggest that, relative to a normal stress response, primary and secondary adrenal insufficiency can occur in severe malaria but may be attenuated by increased circulating interleukin-6 concentrations and impaired cortisol metabolism. The benefits of stress-dose corticosteroid replacement are unknown but could be considered in hypoglycemic patients or those with a serum cortisol within or below the reference range.


Assuntos
Citocinas/fisiologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Malária Falciparum/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Hormônio Adrenocorticotrópico/sangue , Adulto , Hormônio Liberador da Corticotropina , Citocinas/sangue , Feminino , Humanos , Hidrocortisona/sangue , Malária Falciparum/sangue , Malária Falciparum/diagnóstico , Masculino , Pessoa de Meia-Idade , Nitratos/sangue , Hormônios Tireóideos/sangue
6.
Neuroscience ; 116(1): 13-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12535932

RESUMO

Activation of the extracellular signal-related kinase is important for long-term increases in synaptic strength in the Aplysia nervous system. However, there is little known about the mechanism for the activation of the kinase in this system. We examined the activation of Aplysia extracellular signal-related kinase using a phosphopeptide antibody specific to the sites required for activation of the kinase. We found that phorbol esters led to a prolonged activation of extracellular signal-related kinase in sensory cells of the Aplysia nervous system. Surprisingly, inhibitors of protein kinase C did not block this activation. Serotonin, the physiological transmitter involved in long-term synaptic facilitation, also led to prolonged activation of extracellular signal-related kinase, but inhibitors of protein kinase A or protein kinase C did not block this activation. We examined whether the protein synthesis-dependent increase in excitability stimulated by phorbol esters was dependent on phorbol ester activation of extracellular signal-related kinase, but increases in excitability were still seen in the presence of inhibitors of extracellular signal-related kinase activation. Our results suggest that prolonged phosphorylation of extracellular signal-related kinase in the Aplysia system is not mediated by either of the classic second messenger activated kinases in this system, protein kinase A or protein kinase C and that extracellular signal-related kinase is not important for phorbol ester induced long-term effects on excitability.


Assuntos
Aplysia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Sistema Nervoso/efeitos dos fármacos , Sistema Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Proteína Quinase C/metabolismo , Serotonina/metabolismo , Animais , Western Blotting , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ativadores de Enzimas/farmacologia , Imuno-Histoquímica , Ésteres de Forbol/farmacologia , Proteína Quinase C/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
7.
DNA Cell Biol ; 16(3): 347-56, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9115644

RESUMO

Voltage-gated Na+ channels generate the depolarizing inward current that is critical for the initiation and conduction of action potentials. To study the roles of Na+ channels in neuronal signaling, we have begun the molecular analysis of Na+ channels in Aplysia californica. We have isolated cDNAs that encode a neuronal Na+ channel alpha-subunit, which we have named SCAP1. DNA sequence analysis of the SCAP1 cDNA revealed an open reading frame that predicts a protein of 1,993 amino acids, which is highly similar to other members of the Na+ channel alpha-subunit gene family. RNase protection assays carried out on various Aplysia tissues indicated that SCAP1 is expressed predominantly in the nervous system. All of the nonneuronal tissues tested were negative with the exceptions that low levels of expression were observed in ovotestis and parapodium, probably due to the presence of small numbers of neurons within these tissue preparations. Southern blot hybridization at reduced stringency indicated that the genome of Aplysia contains more than one Na+ channel alpha-subunit gene.


Assuntos
Aplysia/genética , DNA Complementar/genética , Canais de Sódio/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Regulação da Expressão Gênica , Dados de Sequência Molecular , Alinhamento de Sequência
8.
J Virol Methods ; 60(2): 161-70, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8844622

RESUMO

Human immunodeficiency virus type 1 (HIV-1) is transmitted by infected males in semen. However, the inoculum required for infection is unknown. The ability to collect such information will rely on the availability of reliable quantitative assays of HIV-1 in semen. We examined the comparative performance of NASBA and Amplicor Monitor RT-PCR in quantifying HIV-1 RNA in cell free seminal plasma from seropositive men and correlated the results obtained with viral titres measured by a seminal cell quantitative microculture (QMC) assay. Of samples analysed, 68% and 56% by both NASBA and RT-PCR contained measurable HIV-1 RNA, respectively. Amplification inhibition frequently affected RT-PCR but not NASBA. Excluding samples with complete RT-PCR inhibition, there was 90% qualitative concordance and a strong positive correlation (r = 0.86) of RNA levels measured by the two methods. Comparison of the concentration of HIV-1 RNA in seminal plasma samples, as measured by NASBA, with QMC viral titres indicated that RNA levels probably reflect the infectiousness of whole semen. NASBA is a reliable technique for quantitating HIV-1 RNA in seminal plasma and should become a valuable tool in the study of factors that influence the sexual transmission of HIV.


Assuntos
Infecções por HIV/virologia , HIV-1/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , RNA Viral/isolamento & purificação , Sêmen/virologia , Carga Viral/métodos , Estudos de Avaliação como Assunto , HIV-1/genética , Humanos , Masculino , Técnicas de Amplificação de Ácido Nucleico , RNA Viral/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
J Am Diet Assoc ; 86(6): 752-8, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3519737

RESUMO

Nutrition counselors in the Multiple Risk Factor Intervention Trial (MRFIT) were able to help middle-aged men who were at high risk for coronary heart disease change their dietary habits, maintain those changes over time, and decrease their serum cholesterol levels. Most of a 7.5% mean serum cholesterol reduction achieved after 6 years of nutrition intervention occurred during the first year of the trial and was thereafter sustained. Total cholesterol and low-density lipoprotein cholesterol fraction decreases indicated improvement in terms of coronary heart disease risk. The food record rating, a numerical, semi-objective adherence technique that assesses a 3-day food record with respect to lipid-lowering potential, was used throughout the trial to measure adherence to recommended food patterns. Participants with lower food record rating scores, which indicate better adherence, demonstrated greater reductions in serum total cholesterol, plasma total cholesterol, and low-density lipoprotein fraction cholesterol determinations on a group basis. Subjective evaluations of the suitability of home and working environments, evidence of deviation from the MRFIT food patterns, and overall nutrition program motivation also showed that as ratings in each category became more favorable, lower food record rating scores and greater blood lipid reductions were consistently observed. The subgroup of participants who were non-smokers and not hypertensive demonstrated greater lipid responses and better dietary adherence. Continued smoking and antihypertensive medications appeared to adversely influence dietary adherence and/or lipid reductions. The MRFIT experience, however, demonstrated for the first time that dietary changes and blood lipid reductions can be achieved after the initial intervention effect, despite a continued emphasis on high blood pressure management and smoking cessation.


Assuntos
Doença das Coronárias/prevenção & controle , Dieta , Comportamento Alimentar , Lipídeos/sangue , Cooperação do Paciente , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , VLDL-Colesterol , Ensaios Clínicos como Assunto , Ingestão de Energia , Métodos Epidemiológicos , Humanos , Hipertensão/complicações , Lipoproteínas VLDL/sangue , Masculino , Pessoa de Meia-Idade , Distribuição Aleatória , Risco , Fumar
10.
J Infect ; 30(2): 147-51, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7636281

RESUMO

Cytomegalovirus (CMV) is an increasingly important opportunistic pathogen in patients with HIV infection and advanced immune deficiency. Neurological complications due to CMV cause significant morbidity but may be treatable with specific anti-viral therapy: cerebral mass lesions are not a generally recognised manifestation. We report two patients with CMV encephalitis presenting as a cerebral mass lesion, with simultaneous occurrence of a pleuro-pulmonary mass also caused by CMV in one case, and with concurrent polyradiculomyelopathy in the other. The spectrum of previously reported clinical and radiological features of CNS involvement in AIDS is discussed. CMV should be considered in the differential diagnosis of cerebral mass lesions in patients with HIV infection and severe immune deficiency so that anti-viral therapy can be rapidly deployed.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/virologia , Encefalopatias/virologia , Infecções por Citomegalovirus/virologia , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico por imagem , Adulto , Encefalopatias/diagnóstico por imagem , Infecções por Citomegalovirus/diagnóstico por imagem , Diagnóstico Diferencial , Soropositividade para HIV/complicações , Homossexualidade Masculina , Humanos , Masculino , Tomografia Computadorizada por Raios X
11.
J Infect ; 31(3): 181-8, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8586836

RESUMO

In order to examine the effects of platelet-activating factor (PAF) in complicated Plasmodium falciparum infections, plasma concentrations of lyso-PAF, stable metabolite and principal precursor of PAF, were measured in 25 Vietnamese adults with severe malaria. The concentration of PAF in the cerebrospinal fluid (CSF) was determined in a sub-group of 23 comatose patients and, together with that of lyso-PAF, in the plasma of 20 patients on recovery of consciousness. The concentration of lyso-PAF in the plasma was depressed on admission to hospital (median [range]; 21 [8-143] vs. 293 [215-410] ng/ml in 10 controls; P < 0.001). There was, however, no change in plasma activity of acetylhydrolase which converts PAF to lyso-PAF (P > 0.01 vs. controls) while simultaneous reduction in the concentration of lipoproteins associated with lyso-PAF were less than those of lyso-PAF per se in the plasma. The plasma concentration of lyso-PAF on admission was associated with parasitaemia and the concentration of serum triglycerides (rs = -0.42, P = 0.04 in each case), the latter being consistent with hepatic effects of PAF reported in previous studies. CSF concentrations of PAF on admission were low (2.3 [0.5-7.7] vs. 0.9 [0-2.5] ng/ml after recovery, P < 0.01) compared with values reported previously in bacterial meningitis. Plasma concentrations of lyso-PAF after recovery lay between admission and control values. While increased availability of PAF may reflect parasite burden and may modulate liver-mediated metabolic disturbances such as hypoglycaemia and lactic acidosis, the role of PAF in cerebral malaria is uncertain.


Assuntos
Malária Cerebral/metabolismo , Malária Falciparum/metabolismo , Fator de Ativação de Plaquetas/análogos & derivados , Fator de Ativação de Plaquetas/metabolismo , Adulto , Antimaláricos/uso terapêutico , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Coma/metabolismo , Feminino , Humanos , Unidades de Terapia Intensiva , Metabolismo dos Lipídeos , Malária Cerebral/tratamento farmacológico , Malária Falciparum/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Fator de Ativação de Plaquetas/líquido cefalorraquidiano , Vietnã/etnologia , Austrália Ocidental
17.
Infect Control Hosp Epidemiol ; 29(9): 859-65, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18684094

RESUMO

OBJECTIVE: To describe an outbreak of invasive methicillin-resistant Staphylococcus aureus (MRSA) infection after percutaneous needle procedures (acupuncture and joint injection) performed by a single medical practitioner. SETTING: A medical practitioner's office and 4 hospitals in Perth, Western Australia. PATIENTS: Eight individuals who developed invasive MRSA infection after acupuncture or joint injection performed by the medical practitioner. METHODS: We performed a prospective and retrospective outbreak investigation, including MRSA colonization surveillance, environmental sampling for MRSA, and detailed molecular typing of MRSA isolates. We performed an infection control audit of the medical practitioner's premises and practices and administered MRSA decolonization therapy to the medical practitioner. RESULTS: Eight cases of invasive MRSA infection were identified. Seven cases occurred as a cluster in May 2004; another case (identified retrospectively) occurred approximately 15 months earlier in February 2003. The primary sites of infection were the neck, shoulder, lower back, and hip: 5 patients had septic arthritis and bursitis, and 3 had pyomyositis; 3 patients had bacteremia, including 1 patient with possible endocarditis. The medical practitioner was found to be colonized with the same MRSA clone [ST22-MRSA-IV (EMRSA-15)] at 2 time points: shortly after the first case of infection in March 2003 and again in May 2004. After the medical practitioner's premises and practices were audited and he himself received MRSA decolonization therapy, no further cases were identified. CONCLUSIONS: This outbreak most likely resulted from a breakdown in sterile technique during percutaneous needle procedures, resulting in the transmission of MRSA from the medical practitioner to the patients. This report demonstrates the importance of surveillance and molecular typing in the identification and control of outbreaks of MRSA infection.


Assuntos
Terapia por Acupuntura/efeitos adversos , Surtos de Doenças , Transmissão de Doença Infecciosa do Profissional para o Paciente , Injeções/efeitos adversos , Resistência a Meticilina , Infecções Estafilocócicas , Staphylococcus aureus/efeitos dos fármacos , Adulto , Idoso , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Artrite Infecciosa/terapia , Feminino , Pessoal de Saúde , Humanos , Controle de Infecções/métodos , Masculino , Pessoa de Meia-Idade , Piomiosite/terapia , Articulação do Ombro/efeitos dos fármacos , Articulação do Ombro/microbiologia , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/transmissão , Staphylococcus aureus/classificação , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Austrália Ocidental/epidemiologia
18.
Neurochem Res ; 13(6): 517-23, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2970016

RESUMO

The methionine (MET) derivative, S-adenosylmethionine (SAM), provides methyl-groups for methylation reactions in many neural processes. In rats made diabetic with streptozotocin (SZ), brain SAM levels were generally lower (10-20%) than in controls, with a constant decrease being observed five weeks after onset of diabetes. This decrease in SAM levels may be due to reduced precursor (MET) availability because greatly elevating plasma MET concentrations in SZ diabetic rats by dietary manipulation increased their neural SAM concentrations to be approximately or even greater than (5-20%) those of controls. In contrast, neural levels of SAM's demethylated product, S-adenosylhomocysteine (SAH), were reduced to a greater extent (17-44%) than SAM levels in all groups of SZ diabetic rats independent of their plasma MET concentrations or brain SAM levels. This indicates that the decrease in SAH levels is not simply due to substrate (SAM) restriction. These changes in MET metabolites appear to be a general effect of diabetes rather than a non-pancreatic side-effect of SZ, because genetically diabetic BB Wistar rats also exhibited reduced brain SAM (25%) and brain SAH (46%) levels. These results indicate that methyl-groups from MET are handled differently in the brain of the diabetic rat, which considering the variety and importance of neural methylation reactions, could have important consequences for the diabetic.


Assuntos
Encéfalo/metabolismo , Diabetes Mellitus Experimental/metabolismo , Homocisteína/análogos & derivados , Metionina/sangue , S-Adenosil-Homocisteína/metabolismo , S-Adenosilmetionina/metabolismo , Administração Oral , Animais , Caseínas/administração & dosagem , Dieta , Feminino , Masculino , Ratos , Ratos Endogâmicos , Estreptozocina , Fatores de Tempo
19.
ASDC J Dent Child ; 49(1): 19-21, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6948831

RESUMO

Twenty-two orthodontic patients in the eleven to fifteen-year age-group participated in a one-year fluoride rinsing program. A 0.1 percent SnF2 solution was compared to a MFP solution containing an equivalent amount of fluoride. A laboratory study evaluated the enamel solubility reducing capacities of the two solutions. Enamel solubility reduction by a two-minute treatment with 0.1 percent SnF2 was 77.8 percent; that for MFP solution was only 13.1 percent. Rinsing daily with SnF2 prevented decalcification completely in twelve patients; two of ten patients rinsing with MFP developed new decalcification during orthodontic treatment. Thus, SnF2 was more effective than MFP in both the laboratory and clinical phases of the study. These results support the requirement for frequent applications, if patients are at advanced risk, and suggest that the method of treatment is at least as important as the choice of specific fluoride.


Assuntos
Fluoretos/uso terapêutico , Aparelhos Ortodônticos/efeitos adversos , Fosfatos/uso terapêutico , Fluoretos de Estanho/uso terapêutico , Doenças Dentárias/prevenção & controle , Adolescente , Criança , Cárie Dentária/prevenção & controle , Solubilidade do Esmalte Dentário , Humanos , Antissépticos Bucais/uso terapêutico
20.
J Neurochem ; 56(6): 1921-31, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1673995

RESUMO

Changing the dietary ratio of the essential fatty acids (EFA), 18:2n6 and 18:3n3, while keeping the amounts of other fatty acids in the diet constant can rapidly and specifically alter the proportions of n6 and n3 22-carbon fatty acids in the brain of the weanling rat. A dietary 18:2n6/18:3n3 ratio of 165 versus 1.8 caused higher n6 and lower n3 22-carbon fatty acid levels, without changing total 22-carbon fatty acid levels, in phosphatidylethanolamine and phosphatidylcholine from several neural membrane fractions. This was apparent after only 2 weeks and showed no sign of plateauing after 12 weeks. Other neural fatty acids were essentially unaffected. The three most abundant 22-carbon fatty acids responded somewhat differently to increments in the dietary 18:2n6/18:3n3 ratio (1.8, 9, 36, and 165). Levels of 22:4n6 increased by similar absolute amounts for each four-fold increase in dietary 18:2n6/18:3n3 ratio; in contrast, the largest absolute changes in 22:5n6 and 22:6n3 levels occurred as the 18:2n6/18:3n3 ratio increased from 36 to 165. This study shows that the 18:2n6/18:3n3 ratio of diets high in fat (40% of energy) and adequate in EFA, both typical of diets in developed countries, can substantially and relatively quickly affect the 22-carbon fatty acids in the brain, even after the rapid accumulation of these fatty acids during neural growth has ceased.


Assuntos
Gorduras na Dieta/farmacologia , Ácidos Graxos/metabolismo , Ácidos Linoleicos/farmacologia , Ácidos Linolênicos/farmacologia , Sistema Nervoso/metabolismo , Animais , Carbono , Ácidos Graxos/química , Ácido Linoleico , Masculino , Ratos , Ratos Endogâmicos , Fatores de Tempo , Desmame , Ácido alfa-Linolênico
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