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1.
Anal Chim Acta ; 1104: 105-109, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32106940

RESUMO

Solid-state 13C and 19F NMR spectroscopy offers a non-destructive, highly selective protocol for the identification of forensically relevant synthetic cannabinoids on herbal substrates. Using this technique, well resolved 13C spectra were obtained that readily enabled structural identification; in some instances complemented by 19F spectral data. The approach described has potential for related applications such as the direct detection of pesticides on plants.


Assuntos
Canabinoides/análise , Drogas Desenhadas/análise , Ressonância Magnética Nuclear Biomolecular/métodos , Preparações de Plantas/química , Turnera/química , Canabinoides/química , Drogas Desenhadas/química , Estrutura Molecular
2.
Eur J Pharm Biopharm ; 96: 484-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25758122

RESUMO

The effectiveness of delivering oral therapeutic peptides, proteins and nucleotides is often hindered by the protective mucus barrier that covers mucosal surfaces of the gastrointestinal (GI) tract. Encapsulation of active pharmaceutical ingredients (API) in nanocarriers is a potential strategy to protect the cargo but they still have to pass the mucus barrier. Decorating nanoparticles with proteolytic enzymes has been shown to increase the permeation through mucus. Here we investigate the effect of poly(acrylic acid) (PAA) nanoparticles decorated with bromelain (BRO), a proteolytic enzyme from pineapple stem, on the bulk rheology of mucus as well as non-decorated poly(lactic-co-glycolic acid) (PLGA) nanoparticles. Porcine intestinal mucus from the small intestine was incubated for 30min in the presence of PLGA nanoparticles or polyacrylic nanoparticles decorated with bromelain (PAA-BRO). The effect of nanoparticles on the rheological properties, weight of gel, released glycoprotein content from mucus as well as the viscosity of liquid removed was assessed. Treatment with nanoparticles decreased mucus gel strength with PAA-BRO reducing it the most. PAA-BRO nanoparticles resulted in the release of increased glycoprotein from the gel network whereas mucus remained a gel and exhibited a similar breakdown stress to control mucus. Therefore it would be possible to use bromelain to increase the permeability of nanoparticles through mucus without destroying the gel and leaving the underlying mucosa unprotected.


Assuntos
Resinas Acrílicas/química , Bromelaínas/metabolismo , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Muco/metabolismo , Nanopartículas/química , Matadouros , Ananas/enzimologia , Animais , Portadores de Fármacos , Enzimas Imobilizadas/metabolismo , Glicoproteínas/metabolismo , Ácido Láctico/química , Muco/química , Permeabilidade , Proteínas de Plantas/metabolismo , Caules de Planta/enzimologia , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Reologia , Propriedades de Superfície , Sus scrofa , Viscosidade
3.
Clin Pharmacol Ther ; 97(6): 628-40, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25704128

RESUMO

With increasing use of herbal medicines for chronic or serious illness, relevant quality assurance methods are essential for making claims of therapeutic benefit. Adequate demonstration of safety and efficacy based on chemical composition and ensuring consistency between manufactured batches is critical. To date, there has been no uniform standard approach or detailed framework provided to industry for selecting relevant chemical markers used to standardize herbal products. We developed the Herbal Marker Ranking System (Herb MaRS) providing guidance on prioritizing the selection of chemical markers for quality control of complex multi-herb mixtures, while also taking into account the bioactivity in relation to the symptoms of the disease and its concentration in the formula. We apply the Herb MaRS evaluation criteria to a seven-herb formulation for the treatment of irritable bowel syndrome with constipation. Our ranking scale accommodates the clinical and pharmacological use of the formulation and its claimed indications.


Assuntos
Medicina Herbária/normas , Atractylodes , Química Farmacêutica , Citrus , Humanos , Magnolia , Paeonia , Garantia da Qualidade dos Cuidados de Saúde , Controle de Qualidade , Rheum
4.
Exp Physiol ; 98(7): 1156-63, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23585326

RESUMO

Simulated haemorrhage, e.g. lower body negative pressure (LBNP), reduces central blood volume and mean arterial pressure, while ventilation increases. Passive whole-body heat stress likewise increases ventilation. The objective of this project was to test the hypothesis that ventilatory responses to reductions in central blood volume and arterial pressure during simulated haemorrhage are enhanced when individuals are heat stressed rather than normothermic. Eight healthy men (34 ± 9 years old, 176 ± 6 cm tall and 80.2 ± 4.2 kg body weight) underwent a simulated haemorrhagic challenge via LBNP until presyncope on two separate occasions, namely normothermic control and whole-body heat-stress trials. Baseline ventilation and core and mean skin temperatures were not different between trials (all P > 0.05). Prior to LBNP, heat stress increased core (from 36.8 ± 0.2 to 38.2 ± 0.2°C, P < 0.05) and mean skin temperatures (from 33.9 ± 0.5 to 38.1 ± 0.6°C, P < 0.05), as well as minute ventilation (from 8.01 ± 2.63 to 13.68 ± 6.68 l min(-1), P < 0.01). At presyncope, mean arterial pressure and middle cerebral artery blood velocity decreased in both trials (P < 0.05). At presyncope, ventilation increased to 23.22 ± 6.78 (P < 0.01) and 25.88 ± 10.16 l min(-1) (P < 0.01) in the normothermic and hyperthermic trials, respectively; however, neither the increase in ventilation from the pre-LBNP period nor the absolute ventilation was different between normothermic and hyperthermic trials (P > 0.05). These data suggest that the increase in ventilation during simulated haemorrhage induced via LBNP is not altered in heat-stressed humans.


Assuntos
Pressão Arterial/fisiologia , Resposta ao Choque Térmico/fisiologia , Temperatura Cutânea/fisiologia , Síncope/fisiopatologia , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Volume Sanguíneo/fisiologia , Hemorragia/fisiopatologia , Humanos , Hipertermia Induzida/métodos , Pressão Negativa da Região Corporal Inferior/métodos , Masculino
5.
Exp Physiol ; 98(2): 444-50, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22903981

RESUMO

During a simulated haemorrhagic challenge, syncopal symptoms develop sooner when individuals are hyperthermic relative to normothermic. This is due, in part, to a large displacement of blood to the cutaneous circulation during hyperthermia, coupled with inadequate cutaneous vasoconstriction during the hypotensive challenge. The influence of local skin temperature on these cutaneous vasoconstrictor responses is unclear. This project tested the hypothesis that local skin temperature modulates cutaneous vasoconstriction during simulated haemorrhage in hyperthermic humans. Eight healthy participants (four men and four women; 32 ± 7 years old; 75.2 ± 10.8 kg) underwent lower-body negative pressure to presyncope while heat stressed via a water-perfused suit sufficiently to increase core temperature by 1.2 ± 0.2 °C. At forearm skin sites distal to the water-perfused suit, local skin temperature was either 35.2 ± 0.6 (mild heating) or 38.2 ± 0.2 °C (moderate heating) throughout heat stress and lower-body negative pressure, and remained at these temperatures until presyncope. The reduction in cutaneous vascular conductance during the final 90 s of lower-body negative pressure, relative to heat-stress baseline, was greatest at the mildly heated site (-10 ± 15% reduction) relative to the moderately heated site (-2 ± 12%; P = 0.05 for the magnitude of the reduction in cutaneous vascular conductance between sites), because vasoconstriction at the moderately heated site was either absent or negligible. In hyperthermic individuals, the extent of cutaneous vasoconstriction during a simulated haemorrhage can be modulated by local skin temperature. In situations where skin temperature is at least 38 °C, as is the case in soldiers operating in warm climatic conditions, a haemorrhagic insult is unlikely to be accompanied by cutaneous vasoconstriction.


Assuntos
Transtornos de Estresse por Calor/fisiopatologia , Resposta ao Choque Térmico , Hemorragia/fisiopatologia , Temperatura Cutânea , Pele/irrigação sanguínea , Vasoconstrição , Adulto , Pressão Arterial , Feminino , Transtornos de Estresse por Calor/complicações , Hemorragia/complicações , Humanos , Hipertermia Induzida , Pressão Negativa da Região Corporal Inferior , Masculino , Síncope/etiologia , Síncope/fisiopatologia , Fatores de Tempo
6.
Acta Neuropsychiatr ; 21(3): 133-40, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26953751

RESUMO

BACKGROUND: The protein product of INSIG2 is involved in cholesterol and triglyceride metabolism and homeostasis. Variation at rs7566605 near the gene INSIG2 has been associated with increased BMI. OBJECTIVE: To evaluate the effect of rs7566605/INSIG2 genotype on the ability of valproate-treated bipolar patients (BMI ≥ 25 kg/m2) to lose weight using carnitine supplementation during a 26-week lifestyle intervention study. DESIGN: Forty-eight bipolar patients with clinically significant treatment emergent weight gain were genotyped at the rs7566605 SNP. Participants were randomised to l-carnitine (15 mg/kg/day) or placebo for 26 weeks in conjunction with a moderately energy restricted, low-fat diet. Weight and body fat percent were measured fortnightly. Waist circumference measurements and dual-energy X-ray absorptiometry were used to assess changes in body composition. Obesity-related biomarkers were measured at baseline and 26 weeks. RESULTS: There was a significant interaction between rs7566605/INSIG2 genetic status and treatment with carnitine or placebo. Carnitine had no significant effect on body composition measures in G allele homozygous patients who lost between 0.97 and 2.23 kg of fat. However C allele carriers on average gained 2.28 kg when given a placebo. Carnitine supplementation in this group enabled average weight loss of 2.22 kg of fat (p = 0.01). Approximately half of this mass was in the vital truncal compartment (p = 0.002). Bioinformatic analysis detected that the SNP lies in a highly conserved 336 bp sequence which potentially affects INSIG2 gene expression. CONCLUSIONS: C-carriers at rs7566605, possibly regulating the homeostasis gene INSIG2, lost significantly less weight in this lifestyle intervention study. This effect was reversed by carnitine supplementation.

7.
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
8.
Xenobiotica ; 38(3): 264-80, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18274956

RESUMO

Usnic acid is a component of nutritional supplements promoted for weight loss that have been associated with liver-related adverse events including mild hepatic toxicity, chemical hepatitis, and liver failure requiring transplant. To determine if metabolism factors might have had a role in defining individual susceptibility to hepatotoxicity, in vitro metabolism studies were undertaken using human plasma, hepatocytes, and liver subcellular fractions. Usnic acid was metabolized to form three monohydroxylated metabolites and two regio-isomeric glucuronide conjugates of the parent drug. Oxidative metabolism was mainly by cytochrome P450 (CYP) 1A2 and glucuronidation was carried out by uridine diphosphate-glucuronosyltransferase (UGT) 1A1 and UGT1A3. In human hepatocytes, usnic acid at 20 microM was not an inducer of CYP1A2, CYP2B6, or CYP3A4 relative to positive controls omeprazole, phenobarbital, and rifampicin, respectively. Usnic acid was a relatively weak inhibitor of CYP2D6 and a potent inhibitor of CYP2C19 (the concentration eliciting 50% inhibition (IC(50)) = 9 nM) and CYP2C9 (IC(50) = 94 nM), with less potent inhibition of CYP2C8 (IC(50) = 1.9 microM) and CYP2C18 (IC(50) = 6.3 microM). Pre-incubation of microsomes with usnic acid did not afford any evidence of time-dependent inhibition of CYP2C19, although evidence of slight time-dependent inhibition of CYP2C9 (K(I) = 2.79 microM and K(inact) = 0.022 min(-1)) was obtained. In vitro data were used with SimCYP(R)to model potential drug interactions. Based on usnic acid doses in case reports of 450 mg to >1 g day(-1), these in vitro data indicate that usnic acid has significant potential to interact with other medications. Individual characteristics such as CYP1A induction status, co-administration of CYP1A2 inhibitors, UGT1A1 polymorphisms, and related hyperbilirubinaemias, or co-administration of low therapeutic index CYP2C substrates could work alone or in consort with other idiosyncrasy risk factors to increase the risk of adverse events and/or hepatotoxicity. Thus, usnic acid in nutritional supplements might be involved as both victim and/or perpetrator in clinically significant drug-drug interactions.


Assuntos
Benzofuranos/efeitos adversos , Benzofuranos/metabolismo , Doença Hepática Induzida por Substâncias e Drogas , Suplementos Nutricionais/efeitos adversos , Benzofuranos/química , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/biossíntese , Interações Medicamentosas , Indução Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Humanos , Concentração Inibidora 50 , Cinética , Hepatopatias/enzimologia , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Modelos Moleculares , Ligação Proteica/efeitos dos fármacos , Fatores de Risco , Especificidade por Substrato/efeitos dos fármacos
9.
Crit Rev Food Sci Nutr ; 45(6): 497-510, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16183570

RESUMO

Alginate, an algal polysaccharide, is widely used in the food industry as a stabilizer, or as a thickening or emulsifying agent. As an indigestible polysaccharide, alginate may also be viewed as a source of dietary fiber. Previous work has suggested that dietary fibres may protect against the onset and continuation of a number of cardiovascular and gastrointestinal diseases. This article aims to examine what is currently understood about the fiber-like activities of alginate, particularly its effects on intestinal absorption and the colon, and therefore aims to gauge the potential use of alginate as a dietary supplement for the maintenance of normal health, or the alleviation of certain cardiovascular or gastrointestinal diseases.


Assuntos
Alginatos , Fibras na Dieta , Gastroenteropatias/prevenção & controle , Ácido Glucurônico , Ácidos Hexurônicos , Humanos
10.
Am J Health Promot ; 15(6): 422-32, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11523499

RESUMO

PURPOSE: To determine if participation in a Wellness-Based Mindfulness Stress Reduction intervention decreases the effect of daily hassles, psychological distress, and medical symptoms. DESIGN: A randomized controlled trial of a stress reduction intervention with a 3-month follow-up. SETTING: A university setting in West Virginia. SUBJECTS: A total of 103 adults, with 59 in the intervention group and 44 in the control group. Eight-five percent of subjects completed the intervention. Fifty-nine percent and 61% of the intervention and control subjects completed the study, respectively. INTERVENTION: The intervention consisted of an 8-week group stress reduction program in which subjects learned, practiced, and applied "mindfulness meditation" to daily life situations. The control group received educational materials and were encouraged to use community resources for stress management. MEASURES: The Daily Stress Inventory assessed the effect of daily hassles, the Revised Hopkins Symptom Checklist measured psychological distress, the Medical Symptom Checklist measured number of medical symptoms, and a Follow-up Questionnaire measured program adherence. RESULTS: Intervention subjects reported significant decreases from baseline in effect of daily hassles (24%), psychological distress, (44%), and medical symptoms (46%) that were maintained at the 3-month follow-up compared to control subjects (repeated measures analysis of variance [ANOVA]; p < .05). CONCLUSIONS: Self-selected community residents can improve their mental and physical health by participating in a stress reduction intervention offered by a university wellness program.


Assuntos
Promoção da Saúde/normas , Avaliação de Programas e Projetos de Saúde , Terapia de Relaxamento , Estresse Psicológico/terapia , Adulto , Feminino , Educação em Saúde/organização & administração , Promoção da Saúde/organização & administração , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Cooperação do Paciente , População Rural , Inquéritos e Questionários , West Virginia
11.
J Chem Neuroanat ; 16(1): 43-55, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9924972

RESUMO

The distribution of cell bodies immunoreactive for tyrosine hydroxylase and aromatic L-amino acid decarboxylase was studied in the adult human hypothalamus. Many neurons in the posterior (A11) and caudal dorsal hypothalamic areas (A13) as well as in the arcuate (A12) and periventricular (A14) zone were immunoreactive for the two enzymes, suggesting that they were dopaminergic. Numerous tyrosine hydroxylase-immunoreactive neurons, which were not immunoreactive for aromatic L-amino acid decarboxylase, could be seen in the paraventricular, supraoptic and accessory nuclei (A15) as well as in the rostral dorsal hypothalamic area. These were considered to be non-dopaminergic. Conversely, large numbers of small neurons immunoreactive for aromatic L-amino acid decarboxylase but not for tyrosine hydroxylase, were identified in the premammillary nucleus (D8), zona incerta (D10), lateral hypothalamic area (D11), anterior portion of the dorsomedial nucleus (D12), suprachiasmatic nucleus (D13), medial preoptic area and bed nucleus of the stria terminalis (D14). In the human hypothalamus, besides dopaminergic cell bodies, there exists a large number of tyrosine hydroxylase-only and aromatic L-amino acid decarboxylase-only neurons, whose physiological roles remain to be determined.


Assuntos
Descarboxilases de Aminoácido-L-Aromático/metabolismo , Hipotálamo/enzimologia , Tirosina 3-Mono-Oxigenase/metabolismo , Idoso , Idoso de 80 Anos ou mais , Humanos , Hipotálamo/citologia , Hipotálamo Anterior/enzimologia , Hipotálamo Posterior/enzimologia , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Fixação de Tecidos
12.
Br J Obstet Gynaecol ; 105(12): 1256-61, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9883916

RESUMO

OBJECTIVE: To use information collected by the Confidential Enquiry into Stillbirths and Deaths in Infancy to help obstetric, midwifery and paediatric practice in the management of shoulder dystocia. DESIGN: Review of casenotes by a multidisciplinary focus group. SAMPLE: All 56 cases reported to the Confidential Enquiry into Stillbirths and Deaths in Infancy from England, Wales and Northern Ireland in 1994 and 1995, where stillbirth or neonatal death was attributed to shoulder dystocia. MAIN OUTCOME MEASURES: Case notes were reviewed with respect to a range of perinatal variables. Comparisons were made with normative data from other studies when appropriate. RESULTS: Maternal obesity and big babies were over-represented in pregnancies complicated by fatal shoulder dystocia. Fetal compromise was recorded in 26% of labours. The median time interval between delivery of the head and the rest of the body was only five minutes. The lead professional at the time the head was delivered was a midwife in 65% of cases. Middle grade or senior obstetric staff were supervising 47% of cases by the time the body was delivered. CONCLUSIONS: Antenatal prediction of shoulder dystocia is imprecise, and the majority of deliveries are attended by midwives. A relatively brief delay in delivery of the shoulders may be associated with a fatal outcome.


Assuntos
Distocia/mortalidade , Morte Fetal/epidemiologia , Autopsia , Peso ao Nascer , Parto Obstétrico , Inglaterra/epidemiologia , Feminino , Humanos , Mortalidade Infantil , Recém-Nascido , Tocologia , Irlanda do Norte/epidemiologia , Gravidez , Ombro , País de Gales/epidemiologia
13.
J Chromatogr A ; 746(2): 277-81, 1996 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-8916558

RESUMO

Over the past decade trifluoroacetic acid (TFA) has become the ion-pairing agent (IPA) of choice for reversed-phase high-performance liquid chromatography (RP-HPLC) of peptides and proteins. Reagent grade TFA is highly pure, water soluble, transparent at 220 nm and readily volatile. A drawback of this universal appeal is that several alternative perfluorinated carboxylic acids tend to be overlooked when TFA does not work in a particular separation. Examples are given comparing TFA selectivity with those of pentafluoropropionic acid, heptafluorobutyric acid, perfluoropentanoic acid, perfluorohexanoic acid and perfluoroheptanoic acid. We have found that increasing the IPA n-alkyl chain length can resolve sample components that otherwise co-elute in the void volume of TFA-based RP-HPLC. Examples are given for the resolution of an oligoglycine series and enhanced selectivity for a bovine hypothalamic extract.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Fluoracetatos/química , Ácido Trifluoracético/química , Animais , Bovinos , Hipotálamo/química , Indicadores e Reagentes , Oligopeptídeos/análise , Padrões de Referência , Espectrofotometria Ultravioleta
14.
Forensic Sci Int ; 76(2): 97-114, 1995 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-8566917

RESUMO

The synthesis of methamphetamine from pseudoephedrine via the reduction with hydriodic acid and red phosphorus was studied and the impurities which were generated, along with the methamphetamine, were investigated. Some of the impurities found have been reported previously, while the diastereoisomers of N-methyl-N-(alpha- methylphenethyl)amino-1-phenyl-2-propanone and the cis-cinnamoyl derivative of methamphetamine are reported here for the first time. Further work on the sequence of reactions occurring in this reduction is also reported.


Assuntos
Ácidos , Estimulantes do Sistema Nervoso Central/análise , Contaminação de Medicamentos , Efedrina/metabolismo , Drogas Ilícitas/análise , Compostos de Iodo , Metanfetamina/análise , Fósforo , Estimulantes do Sistema Nervoso Central/química , Cromatografia Gasosa , Drogas Ilícitas/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Metanfetamina/química , Oxirredução
15.
Biochim Biophys Acta ; 1246(2): 160-6, 1995 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-7819283

RESUMO

Thioether S-methyltransferase catalyzes transfer of the methyl group from S-adenosylmethionine to X in compounds of the structure R-X-R', where X may be sulfur, selenium, or tellurium, and R and R' may be various organic groups. To obtain a cDNA clone of thioether S-methyltransferase, a mouse lung cDNA library in lambda gt11 was screened with a 99 base-pair probe obtained by performing the polymerase chain reaction on oligo(dT) primed, reverse transcribed, mouse lung RNA using two degenerate primers designed from partial amino-acid sequences of the enzyme. The entire coding and 3'-untranslated regions were obtained and sequenced. The predicted protein contains 264 amino-acid residues and has a calculated M(r) of 29,460. The amino-acid sequence of thioether S-methyltransferase contains three motifs characteristic of many methyltransferases and has a high level of identity with the amino-acid sequences of nicotinamide N-methyltransferase and phenylethanolamine N-methyltransferase. However, in spite of the fact that they are both mammalian cytosolic sulfur methyltransferases, the sequences of thioether S-methyltransferase and thiopurine S-methyltransferase share little identity.


Assuntos
Pulmão/enzimologia , Metiltransferases/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/química , Metiltransferases/química , Camundongos , Dados de Sequência Molecular
16.
J Infect Dis ; 170(5): 1248-55, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7963720

RESUMO

The growth of Mycobacterium avium 7497, serovar 4, in cultured human macrophages is enhanced by Fe3+ and serum lipids over 7 days. Iron (1-80 micrograms/mL) added to macrophages cultured in normal serum resulted in 10-fold increases in growth. If iron-supplemented macrophages were cultured in serum from hypertriglyceridemic donors after infection, M. avium growth increased 10(3)- to 10(4)-fold. Without macrophages, differences in bacterial growth between sera were not seen. Removal of very low density lipoprotein (VLDL) eliminated the differences between sera. Isolated VLDL from hyperlipidemic serum resulted in 10(5)-fold increases in growth over that seen with VLDL from normal sera. Accelerated M. avium growth in macrophages cultured with hyperlipidemic serum was partly inhibited by the addition of superoxide dismutase (1000 IU/mL). Results suggest that iron stimulates O2-induced oxidation of VLDL and its subsequent accumulation in macrophages. The resultant iron- and lipid-laden cells become excellent hosts for mycobacterial growth.


Assuntos
Hipertrigliceridemia/sangue , Ferro/farmacologia , Lipoproteínas VLDL/fisiologia , Macrófagos/microbiologia , Mycobacterium avium/crescimento & desenvolvimento , Síndrome da Imunodeficiência Adquirida/sangue , Adulto , Feminino , Humanos , Lipoproteínas VLDL/sangue , Masculino , Pessoa de Meia-Idade , Superóxido Dismutase/farmacologia
17.
Brain Res ; 403(1): 31-42, 1987 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-3548888

RESUMO

Neurotensin-like immunoreactive (NT-IR) neurons are present in discrete subregions of the anterior, medial and lateral thalamic nuclear groups of the human infant brain. The pulvinar is notably rich in such cells. Smaller numbers of cells are present in the ventral group, centromedian nucleus, reticular nuclei and intralaminar nuclei. Neurotensin immunoreactive axons accumulate dorsally in the thalamus and cross the deep white matter. The cerebral cortex contains a rich network of NT-IR axons. The subthalamic nucleus is rich in NT-IR neurons. Within the hypothalamus NT-IR perikarya are present in parts of the lateral and tuberal regions and in the lateral mammillary area. NT-IR axons are widespread being particularly prominent in parts of the tuberal region and the mammillary body.


Assuntos
Diencéfalo/metabolismo , Recém-Nascido/metabolismo , Neurotensina/metabolismo , Humanos , Hipotálamo/metabolismo , Técnicas Imunoenzimáticas , Fibras Nervosas/metabolismo , Núcleos Talâmicos/metabolismo , Tálamo/metabolismo
18.
Pharmacol Biochem Behav ; 24(5): 1175-83, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-2425376

RESUMO

5HT and 5HIAA levels were altered in neonatal males and females by treating them with 100 mg/kg p-chlorophenylalanine (PCPA) or 20 mg/kg 5-hydroxytryptophan (5HTP) over eight days 1 to 7 or 11 to 16 of life. Androgenized females (testosterone propionate given on day 1) were also treated over days 1 to 7. In adulthood the effects of these treatments on sexual behaviour were observed. None of the treatments affected feminine sexual behaviour in either sex. Reduction of 5HT activity by PCPA enhanced masculine sexual behaviour in males and potentiated the defeminizing effect of exogenous testosterone in females. Increasing 5HT by 5HTP antagonised the defeminizing effect of exogenous testosterone. These findings indicate that the lower levels of hypothalamic 5HT and 5HIAA seen in the neonatal males may have some physiological importance, since 5HT appears to antagonise the androgenizing and defeminizing effects of testosterone.


Assuntos
Animais Recém-Nascidos/fisiologia , Hipotálamo/metabolismo , Serotonina/metabolismo , Comportamento Sexual Animal/fisiologia , 5-Hidroxitriptofano/farmacologia , Animais , Feminino , Fenclonina/farmacologia , Ácido Hidroxi-Indolacético/metabolismo , Masculino , Ratos , Fatores Sexuais , Testosterona/farmacologia , Fatores de Tempo
19.
Neurosci Lett ; 41(1-2): 41-7, 1983 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-6316220

RESUMO

Horseradish peroxidase (HRP) was injected into the thalamic ventral tier of squirrel monkey and the brainstem was examined for the presence of HRP-reactive cells in the external cuneate nucleus (ECN), nuclei Z and X, and the mesencephalic nucleus of the trigeminal nerve (MNV). Results indicate that the ECN, Z and X have a direct projection to contralateral ventral tier. Thalamic projecting cells in the ECN are located predominantly in the medial part of this nucleus. The MNV projects bilaterally to the ventral tier but predominantly to the ipsilateral side. Consequently, the present report establishes evidence that the above nuclei, which are known to be extensively interconnected with cerebellum, spinal cord and/or other brainstem nuclei, also have a thalamic projection in a New World primate, (Saimiri sciureus).


Assuntos
Tronco Encefálico/fisiologia , Neurônios/classificação , Transmissão Sináptica , Tálamo/fisiologia , Nervo Trigêmeo/fisiologia , Animais , Mapeamento Encefálico , Tronco Encefálico/citologia , Peroxidase do Rábano Silvestre , Saimiri
20.
J Morphol ; 177(3): 277-99, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6644824

RESUMO

The morphology of neurons in the ventral basal complex (VBC) of the adult opossum (Didelphis virginiana) is described from thick coronal brain sections, using Golgi-, horseradish peroxidase (HRP)-, and Nissl-staining methods. Soma cross-sectional area, dendritic field shape, and the number of appendages (spines) in a defined major branch zone (MBZ) are quantified and statistically analyzed. Results indicate that neurons in opossum VBC have relatively large cell bodies, dendrites which branch in a tufted pattern, and numerous dendritic appendages. These neurons are designated as relay cells because of (1) their tufted dendritic branch patterns, considered characteristic of thalamic relay cells (Ramon-Moliner, '62), and (2) the similarity of their soma sizes with HRP-labeled somata after somatosensory cortical injections. Neurons with traditionally described interneuron morphology do not appear to be present in the VBC of this animal, and, in this respect, the neuronal morphology of opossum VBC is similar to that in rat (McAllister and Wells, '81). Based on statistical analysis of the structural features observed, the presumed relay cells in opossum VBC do not show significant differences in morphology, and consequently are not subdivided into classes. Opossum VBC neurons are recognized as forming a single category in which broad and continuous variations in morphology are indicated. Recognition of a singular class of relay cell is consistent with descriptions for rat and cat VBC (Scheibel and Scheibel, '66), but at variance with a previous report for the primate Galago VBC (Pearson and Haines, '80) subdividing thalamic relay cells into Types I, II, and intermediate categories.


Assuntos
Complexo de Golgi/ultraestrutura , Gambás/anatomia & histologia , Tálamo/ultraestrutura , Animais , Dendritos/ultraestrutura , Neurônios/citologia , Neurônios/ultraestrutura , Tálamo/citologia
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