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1.
Occup Med (Lond) ; 74(1): 86-92, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38070493

RESUMO

BACKGROUND: It is well recognized that some individuals experience persistent symptoms following an initial SARS-CoV-2 infection. Symptoms affect physical, cognitive and mental well-being and can adversely impact activities of daily living, including the ability to work. AIMS: To examine the impact of post-COVID-19 syndrome with respect to effects on quality of life and impact on work in a cohort of people referred to a 'Long COVID' service. METHODS: All triaged patients (over 18 years with symptoms more than 12 weeks since the initial infection) completed a symptom assessment questionnaire. Occupation and working status (at work, at work struggling with symptoms and off work) were also recorded. Impact on function and quality of life was assessed using the EQ5D5L questionnaire. RESULTS: A total of 214 patients (median age 51.0 years, 135 females) were seen from January to September 2021. Analysis of occupational status showed: 18% were working, 40% were working but struggling and 35% had stopped working due to symptoms. Those unable to work reported significantly more fatigue, a greater perception of the need for support and lower quality-of-life scores. CONCLUSIONS: This study shows the extensive impact of post-COVID-19 syndrome on the ability to return to work. Specific return-to-work guidance is needed to support a large proportion of those struggling with the condition. The involvement of the Occupational Health team should form part of the multidisciplinary, collaborative approach to support rehabilitation and improve long-term outcomes for this condition.


Assuntos
COVID-19 , Feminino , Humanos , Pessoa de Meia-Idade , COVID-19/complicações , Síndrome de COVID-19 Pós-Aguda , Atividades Cotidianas , Qualidade de Vida , SARS-CoV-2
2.
Respir Med ; 112: 81-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26874894

RESUMO

INTRODUCTION: CT density correlates with quality of life (QOL) scores and impaired upper zone lung density associates with higher mortality in alpha one antitrypsin deficiency (A1ATD). We hypothesised that decline in CT densitometry would relate to survival or deterioration in QOL in A1ATD. METHODS: All augmentation naïve PiZZ patients in the UK A1ATD registry with ≥ two successive quantitative CT scans were selected. Patients were divided into groups based on CT density decline and the relationship to survival and change in QOL compared by univariate analyses and multivariate Cox regression. Analyses were performed for whole lung, upper zone and lower zone density separately. Exploratory analyses of FEV1 subgroups were conducted. RESULTS: 110 patients were identified; 77 had whole lung and lung zone density recorded on two CT scans, 33 patients had upper zone data only on four scans. Decline in lower zone density associated with survival, even after adjustment for baseline lung density (p = 0.048), however upper zone density and whole lung density decline did not. This difference appeared to be driven by those with FEV1 >30% predicted. CONCLUSION: Rate of change in lung densitometry could predict survival in A1ATD.


Assuntos
Bronquite Crônica/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Enfisema Pulmonar/diagnóstico por imagem , Sistema de Registros , Deficiência de alfa 1-Antitripsina/diagnóstico por imagem , Adulto , Idoso , Bronquite Crônica/fisiopatologia , Progressão da Doença , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Capacidade de Difusão Pulmonar , Enfisema Pulmonar/fisiopatologia , Qualidade de Vida , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , Reino Unido , Capacidade Vital , Deficiência de alfa 1-Antitripsina/mortalidade , Deficiência de alfa 1-Antitripsina/fisiopatologia
3.
Thorax ; 70(10): 939-45, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26141072

RESUMO

INTRODUCTION: The PiSZ genotype results in less severe deficiency of alpha-1 antitrypsin (AAT) than PiZZ. Less is known about phenotypic and prognostic features. METHODS: We studied 699 PiZZ, 126 PiSZ and 316 PiMM patients. All AAT deficiency (AATD) patients were augmentation naive. PiSZ were compared with PiZZ patients for clinical phenotype at baseline including CT findings, smoke exposure, progression of lung disease and survival. Similarly, PiSZ patients diagnosed as a result of investigation for possible lung disease (lung index cases) were compared with PiMM. Multivariable analytical techniques and matching (PiSZ to PiZZ) were employed to account for demographic differences. RESULTS: Pack-years smoked and FEV1 exhibited a negative correlation in PiSZ and ZZ patients (both r=-0.43), with emphysema and COPD occurring more commonly in PiZZ patients at <20 pack-year exposure. In multivariable analyses, PiSZ patients were less likely to have emphysema (p<0.01) and had better survival than PiZZ (p=0.017), but lung function decline did not differ significantly. 42% of PiSZ patients had upper-zone-dominant emphysema on CT scan. Analyses of AAT level confirmed a critical threshold at 11 µM, particularly with regard to phenotypes classical of PiZZ AATD.Significant baseline differences suggested that PiSZ had presented earlier to health services than PiMM. Once this was accounted for, risk of emphysema did not differ between PiSZ and PiMM although survival was lower in PiMM patients (p<0.01). CONCLUSIONS: PiSZ patients are less susceptible to cigarette smoke than PiZZ. The pattern of emphysema may be similar at diagnosis to usual COPD.


Assuntos
Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/etiologia , Deficiência de alfa 1-Antitripsina/complicações , Deficiência de alfa 1-Antitripsina/genética , Adulto , Idoso , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Prognóstico , Doença Pulmonar Obstrutiva Crônica/mortalidade , Sistema de Registros , Estudos Retrospectivos , Fumar , Reino Unido , Deficiência de alfa 1-Antitripsina/mortalidade
4.
Environ Pollut ; 179: 167-76, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23685629

RESUMO

Historic emissions from two zinc smelters have injured the forest on Blue Mountain near Palmerton, Pennsylvania, USA. Seedlings of soybeans and five tree species were grown in a greenhouse in a series of mixtures of smelter-contaminated and reference soils and then phytotoxic thresholds were calculated. As little as 10% Palmerton soil mixed with reference soil killed or greatly stunted seedlings of most species. Zinc was the principal cause of the phytotoxicity to the tree seedlings, although Mn and Cd may also have been phytotoxic in the most contaminated soil mixtures. Calcium deficiency seemed to play a role in the observed phytotoxicity. Exposed soybeans showed symptoms of Mn toxicity. A test of the effect of liming on remediation of the Zn and Mn phytotoxicity caused a striking decrease in Sr-nitrate extractable metals in soils and demonstrated that liming was critical to remediation and restoration.


Assuntos
Manganês/toxicidade , Plântula/efeitos dos fármacos , Poluentes do Solo/toxicidade , Solo/química , Zinco/toxicidade , Monitoramento Ambiental , Metalurgia , Pennsylvania
5.
Psychol Med ; 41(2): 243-50, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20406524

RESUMO

BACKGROUND: International agreement dictates that clients must be help-seeking before any assessment or intervention can be implemented by an 'at-risk service'. Little is known about individuals who decline input. This study aimed to define the size of the unengaged population of an 'at-risk service', to compare this group to those who did engage in terms of sociodemographic and clinical features and to assess the clinical outcomes of those who did not engage with the service. METHOD: Groups were compared using data collected routinely as part of the service's clinical protocol. Data on service use and psychopathology since referral to Outreach and Support in South London (OASIS) were collected indirectly from clients' general practitioners (GPs) and by screening electronic patient notes held by the local Mental Health Trust. RESULTS: Over one-fifth (n=91, 21.2%) of those referred did not attend or engage with the service. Approximately half of this group subsequently received a diagnosis of mental illness. A diagnosis of psychosis was given to 22.6%. Nearly 70% presented to other mental health services. There were no demographic differences, except that those who engaged with the service were more likely to be employed. CONCLUSIONS: Over one-fifth of those referred to services for people at high risk of psychosis do not attend or engage. However, many of this group require mental health care, and a substantial proportion has, or will later develop, psychosis. A more assertive approach to assessing individuals who are at high risk of psychosis but fail to engage may be indicated.


Assuntos
Serviços Comunitários de Saúde Mental/estatística & dados numéricos , Relações Comunidade-Instituição , Aceitação pelo Paciente de Cuidados de Saúde , Transtornos Psicóticos/prevenção & controle , Encaminhamento e Consulta , Adolescente , Adulto , Diagnóstico Precoce , Feminino , Medicina Geral , Humanos , Londres , Masculino , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Estudos Retrospectivos
6.
Xenobiotica ; 40(3): 195-206, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20039779

RESUMO

(R,R)-fenoterol (Fen), a beta(2)-adrenoceptor agonist, is under clinical investigation in the treatment of congestive heart disease. The pharmacokinetics and metabolism of the 4-methoxyphenyl derivative of (R,R)-Fen, (R,R)-MFen, have been determined following intravenous and oral administration to the rat and compared with corresponding results obtained with (R,R)-Fen. Results from the study suggest that (R,R)-MFen can offer pharmacokinetic and metabolic advantages in comparison to an earlier (R,R)-Fen. The oral administration revealed that the net exposure of (R,R)-MFen was about three-fold higher than that of (R,R)-Fen (7.2 versus 2.3 min x nmol ml(-1)), while intravenous administration proved that the clearance was significantly reduced, 48 versus 146 ml min(-1) kg(-1), the T(1/2) was significantly longer, 152.9 versus 108.9 min, and the area under the curve (AUC) was significantly increased, 300 versus 119 min x nmol ml(-1). (R,R)-MFen was primarily cleared by glucuronidation associated with significant presystemic glucuronidation of the compound. After intravenous and oral administration of (R,R)-MFen, (R,R)-Fen and (R,R)-Fen-G were detected in the urine samples indicating that (R,R)-MFen was O-demethylated and subsequently conjugated to (R,R)-Fen-G. The total (R,R)-Fen and (R,R)-Fen-G as a percentage of the dose after intravenous administration was 3.6%, while after oral administration was 0.3%, indicating that only a small fraction of the drug escaped presystemic glucuronidation and was available for O-demethylation. The glucuronidation pattern was confirmed by the results from in vitro studies where incubation of (R,R)-MFen with rat hepatocytes produced (R,R)-MFen-G, (R,R)-Fen and (R,R)-Fen-G, while incubation with rat intestinal microsomes only resulted in the formation of (R,R)-MFen-G.


Assuntos
Fenoterol/análogos & derivados , Fenoterol/metabolismo , Fenoterol/farmacocinética , Administração Oral , Animais , Cromatografia Líquida de Alta Pressão , Fenoterol/química , Fenoterol/urina , Hepatócitos/metabolismo , Injeções Intravenosas , Masculino , Taxa de Depuração Metabólica , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
7.
Am J Drug Alcohol Abuse ; 35(2): 95-102, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19322730

RESUMO

AIMS: Difficulty identifying effective pharmacotherapies for cocaine dependence has led to suggestions that subgroup differences may account for some of the heterogeneity in treatment response. Well-attested methodological difficulties associated with these analyses recommend the use of Bayesian statistical reasoning for evaluation of salient interaction effects. METHODS: A secondary data analysis of a previously published, double-blind, randomized controlled trial examines the interaction of decision-making, as measured by the Iowa Gambling Task, and citalopram in increasing longest sustained abstinence from cocaine use. RESULTS: Bayesian analysis indicated that there was a 99% chance that improved decision-making enhances response to citalopram. Given the strong positive nature of this finding, a formal, quantitative Bayesian approach to evaluate the result from the perspective of a skeptic was applied. CONCLUSIONS: Bayesian statistical reasoning provides a formal means of weighing evidence for the presence of an interaction in scenarios where conventional, Frequentist analyses may be less informative. [Supplementary materials are available for this article. Go to the publisher's online edition of The American Journal of Drug and Alcohol Abuse for the following free supplemental resource: Appendix 1].


Assuntos
Citalopram/uso terapêutico , Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Tomada de Decisões , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Teorema de Bayes , Transtornos Relacionados ao Uso de Cocaína/reabilitação , Método Duplo-Cego , Jogo de Azar/psicologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Psychol Med ; 38(1): 101-11, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17903336

RESUMO

BACKGROUND: Paranoia is increasingly being studied in clinical and non-clinical populations. However there is no multi-dimensional measure of persecutory ideas developed for use across the general population-psychopathology continuum. This paper reports the development of such a questionnaire: the 'Green et al. Paranoid Thought Scales'. The aim was to devise a tool to assess ideas of persecution and social reference in a simple self-report format, guided by a current definition of persecutory ideation, and incorporating assessment of conviction, preoccupation and distress. METHOD: A total of 353 individuals without a history of mental illness, and 50 individuals with current persecutory delusions completed a pool of paranoid items and additional measures to assess validity. Items were devised from a recent definition of persecutory delusions, current assessments of paranoia, the authors' clinical experience, and incorporated dimensions of conviction, preoccupation and distress. Test-retest reliability in the non-clinical group was assessed at 2 weeks follow-up, and clinical change in the deluded group at 6 months follow-up. RESULTS: Two 16-item scales were extracted, assessing ideas of social reference and persecution. Good internal consistency and validity was established for both scales and their dimensions. The scales were sensitive to clinical change. A hierarchical relationship between social reference and persecution was found. The data provide further evidence for a continuum of paranoid ideas between deluded and healthy individuals. CONCLUSIONS: A reliable and valid tool for assessing paranoid thoughts is presented. It will provide an effective way for researchers to ensure consistency in research and for clinicians to assess change with treatment.


Assuntos
Delusões/diagnóstico , Delusões/psicologia , Transtornos Paranoides/diagnóstico , Transtornos Paranoides/psicologia , Adulto , Grupos Controle , Análise Fatorial , Feminino , Seguimentos , Humanos , Relações Interpessoais , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Inventário de Personalidade/estatística & dados numéricos , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Psicometria , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Inquéritos e Questionários , Terminologia como Assunto
9.
Toxicol Pathol ; 34(6): 776-84, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17162535

RESUMO

This article describes the toxicity of alpha-naphthylisothiocyanate (ANIT), a compound known to induce dose-dependent hepatobiliary toxicity in vivo, using the slice model. Liver slices (200 microm thick) from male Sprague-Dawley rats and male beagle dogs were cultured for 7 days while exposed to a range of ANIT concentrations (1- 100 microM for rat and 4-320 microM for dog). Tissues (and medium for dog) were evaluated using a panel of clinically relevant biomarkers for liver and histological endpoints to assess viability and proliferation. ANIT increased slice levels of enzyme biomarkers corresponding to biliary markers. At high concentrations (80-100 microM for rat, 320 microM for dog) a diminution of tissue enzyme levels was observed, corresponding to severe hepatobiliary injury. By days 5 and 7, biochemical markers in the medium of dog slices indicated an elevation of hepatocellular and biliary markers. Histologically for both species, minimal hepatocellular injury was noted, but proliferation of biliary epithelial cells (BEC) was observed using 5-bromo-2-deoxyuridine (BrdU) immunostaining. In rat slices, ANIT increased the expression of inducible nitrous oxide synthase (iNOS) within 12 hrs of exposure. In summary, additional experimentation using slice culture may further demonstrate its value in screening compounds that cause hepatobiliary toxicity.


Assuntos
1-Naftilisotiocianato/toxicidade , Biomarcadores/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Técnicas de Cultura de Tecidos/métodos , Testes de Toxicidade , Alanina Transaminase/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Ductos Biliares Intra-Hepáticos/efeitos dos fármacos , Ductos Biliares Intra-Hepáticos/patologia , Proliferação de Células/efeitos dos fármacos , Cães , Relação Dose-Resposta a Droga , Glicogênio/metabolismo , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie , Fatores de Tempo , gama-Glutamiltransferase/metabolismo
11.
Reproduction ; 122(6): 889-98, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11732984

RESUMO

Cryopreserved spermatozoa demonstrate reduced conception rates compared with fresh spermatozoa when used for artificial insemination. The preliminary stage of cryopreservation of spermatozoa involves cooling to 5 degrees C, during which spermatozoa experience a capacitation-like change, which may be partially responsible for the reduced conception rate observed. The aim of this study was to determine the nature of these capacitation-like changes and how much this process resembles true capacitation. Boar spermatozoa, cooled to 5 degrees C and re-warmed to physiological temperatures (39 degrees C), were compared with spermatozoa capacitated in Tyrode's complete medium (TALP) for 2 h at 39 degrees C. Fluorescent probes, and SDS-PAGE and western blotting were used to visualize events known to occur during capacitation in vitro. Chlortetracycline staining of membrane domains and Fluo-3 detection of changes in intracellular free calcium by flow cytometry in cooled and re-warmed spermatozoa showed similarities to those of capacitated spermatozoa. Alterations to lipid bilayer fluidity assessed by merocyanine fluorescence staining and intracellular signalling pathways detected by tyrosine phosphorylation of cooled and re-warmed spermatozoa, did not completely reflect the changes detected during capacitation in vitro. Thus, cooling spermatozoa to 5 degrees C results in a similar endpoint to that observed in capacitated cells in terms of reactive membranes and changes in intracellular ion concentrations, which may account for their comparable functionality. However, these modifications are not completely analogous and should not be considered true capacitation, but rather a by-passing of the capacitation process.


Assuntos
Temperatura Baixa/efeitos adversos , Capacitação Espermática/fisiologia , Espermatozoides/metabolismo , Animais , Cálcio/análise , Membrana Celular/metabolismo , Células Cultivadas , Clortetraciclina , Corantes , Eletroforese em Gel de Poliacrilamida , Líquido Intracelular/química , Masculino , Fluidez de Membrana , Fosforilação , Pirimidinonas , Espermatozoides/química , Suínos
12.
Biopharm Drug Dispos ; 22(2): 53-71, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11745908

RESUMO

We attempted to predict the in vivo metabolic clearance of alprazolam from in vitro metabolic studies using human liver microsomes and human CYP recombinants. Good correlations were observed between the intrinsic clearance (CL(int)) for 4-hydroxylation and CYP3A4 content and between the CL(int) for alpha-hydroxylation and CYP3A5 content in ten human liver microsomal samples. Using the recombinant CYP isoforms expressed in insect cells, the CL(int) for CYP3A4 was about 2-fold higher than the CL(int) for CYP3A5 in the case of 4-hydroxylation. However, the CL(int) for CYP3A5 was about 3-fold higher than the CL(int) for CYP3A4 in the case of alpha-hydroxylation. The metabolic rates for 4- and alpha-hydroxylation increased as the added amount of cytochrome b(5) increased, and their maximum values were 3- to 4-fold higher than those without cytochrome b(5). The values of CL(int), in vivo predicted from in vitro studies using human liver microsomes and CYP3A4 and CYP3A5 recombinants were within 2.5 times of the observed value calculated from literature data. The average CL(int) value (sum of 4- and alpha-hydroxylation) obtained using three human liver microsomal samples was 4-fold higher than that obtained using three small intestinal microsomal samples from the same donors, indicating the minor contribution of intestinal metabolism to alprazolam disposition. The area under the plasma concentration-time curve (AUC) of alprazolam is reported to increase following co-administration of ketoconazole and the magnitude of the increase predicted from the in vitro K(i) values and reported pharmacokinetic parameters of ketoconazole was 2.30-2.45, which is close to the value observed in vivo (3.19). A quantitative prediction of the AUC increase by cimetidine was also successful (1.73-1.79 vs 1.58-1.64), considering the active transport of cimetidine into the liver. In conclusion, we have succeeded in carrying out an in vitro/in vivo scaling of alprazolam metabolism using human liver microsomes and human CYP3A4 and CYP3A5 recombinants.


Assuntos
Alprazolam/metabolismo , Ansiolíticos/metabolismo , Sistema Enzimático do Citocromo P-450/fisiologia , Oxigenases de Função Mista/fisiologia , Adulto , Área Sob a Curva , Cimetidina/farmacologia , Citocromo P-450 CYP3A , Citocromos b5/fisiologia , Feminino , Humanos , Mucosa Intestinal/metabolismo , Cetoconazol/farmacologia , Masculino , Microssomos Hepáticos/metabolismo , Pessoa de Meia-Idade , Proteínas Recombinantes/metabolismo
13.
J Chromatogr A ; 924(1-2): 471-81, 2001 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-11521899

RESUMO

This paper describes a pharmacokinetic study performed in Sprague-Dawley rats after i.v. administration of a single 6-mg/kg dose of 2beta-carbomethoxy-3beta-(4-fluorophenyl)-N-(3-iodo-E-allyl)nortropane (Altropane). Plasma samples were collected from the retro-orbital sinus at times up to 3 h after drug administration, extracted by solid-phase extraction, and the drug levels determined by capillary electrophoresis (CE). Pharmacokinetic parameters were determined by a standard noncompartmental model using WinNonlin version 1.5. The maximum plasma concentrations, clearances of the drug, and areas under the curve for male and female rats were 5.74 and 7.26 microg/ml, 135.7 and 98.5 ml/kg x min, and 44.23 and 60.92 microg x min/ml, respectively. The drug was cleared very rapidly from the systemic circulation, with a terminal t(1/2) of 7 to 10 min and a mean residence time of about 11 min for both sexes. The volume of distribution was approximately 1 l/kg. No metabolites were detected when the samples were analyzed individually. However, after samples were pooled and concentrated, traces of two unknown peaks that may represent metabolites were detected in concentrates from the last two timepoints. Part I of this work [J. Chromatogr. A, 895 (2000) 87] describes validation of CE methods for the analysis of aqueous and plasma samples of Altropane, including its solid-phase extraction from rat plasma.


Assuntos
Cocaína/sangue , Eletroforese Capilar/métodos , Animais , Área Sob a Curva , Cocaína/análogos & derivados , Cocaína/farmacocinética , Feminino , Masculino , Ratos , Ratos Sprague-Dawley
14.
Reproduction ; 122(2): 305-15, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11467982

RESUMO

After mating, mammalian spermatozoa are transported to the lower oviductal isthmus. Spermatozoa are sequestered at the isthmus by attaching and interacting with oviductal epithelial cells, hence forming a sperm reservoir. In several mammalian species, specific carbohydrates mediate sperm-oviductal epithelial cell binding. A quantitative in vitro free cell bioassay was developed to investigate the involvement of carbohydrate recognition in pig sperm-oviductal epithelial cell interactions. This assay was validated. The sensitivity of the assay was such that it was possible to discriminate between different sperm concentrations and sperm-oviductal epithelial cell co-incubation periods, spermatozoa with damaged plasma membranes and epithelial cells of non-reproductive origin. Optimal conditions were used to incubate spermatozoa and oviductal epithelial cells in the presence of six hexose sugars at concentrations of 0, 2, 10 and 50 mmol l(-1). A significant (P < or = 0.05) reduction in the binding of spermatozoa to the oviductal epithelium was detected with 2, 10 and 50 mmol maltose l(-1), 50 mmol lactose l(-1) and 50 mmol mannose l(-1). These findings support the hypothesis that attachment of pig spermatozoa to oviductal epithelium before fertilization is mediated by carbohydrate recognition.


Assuntos
Carboidratos/farmacologia , Tubas Uterinas/metabolismo , Espermatozoides/metabolismo , Suínos , Animais , Linhagem Celular , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Tubas Uterinas/ultraestrutura , Feminino , Rim , Lactose/farmacologia , Masculino , Maltose/farmacologia , Manose/farmacologia , Microscopia Eletrônica de Varredura
15.
Am J Med ; 110(2): 146, 2001 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11342010

RESUMO

Each month, we will present a challenging Case of the Month for Green Journal readers, who must use their clinical acumen to arrive at the correct answer. We will also post the case each month on the Journal's web site (http://www.elsevier.com/ajmselect). Several possible answers may be consistent with the case presentation; use your best judgment. Please send your answer (one per respondent) to The Green Journal at editors@amjmed.org or via FAX to (415) 447-2799. Indicate the case to which you are responding and include your complete address. The correct answer will appear in the next issue of the Journal. The first five persons who submit correct answers will receive a free one-year subscription to the Journal. Because of the volume of answers we receive, neither correct nor incorrect answers can be individually acknowledged. Colleagues of Drs. Green, Nallamothu, and Shea are not eligible for this month's case. If you would like to contribute a case, please submit a brief synopsis (<250 words) to the editorial office.

17.
J Chromatogr A ; 895(1-2): 87-100, 2000 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-11105851

RESUMO

Altropane, 2beta-carbomethoxy-3beta-(4-fluorophenyl)-N-(3-iodo-E-allyl)nor tropane, is an imaging agent that was developed recently for early detection of Parkinson's disease. Its promise as a useful radiopharmaceutical for single-photon emission computed tomography or positron emission tomography imaging of the brain has been well demonstrated, and it is currently undergoing clinical trials. This paper presents methods development and validation of capillary electrophoresis (CE) techniques to analyze Altropane in aqueous environments as well as in rat plasma, using an internal standard, nicotinamide. N-Allylaltropane, 2beta-carbomethoxy-3beta-(4-fluorophenyl)-N-allylnortropane, which is a known degradation product of the Altropane precursor (tributyltinaltropane), was used to verify the method's specificity. A solid-phase extraction method for extraction of Altropane from rat plasma is also described. The results presented in this paper demonstrate the applicability of CE methods to study the pharmacokinetic properties of Altropane in animal models. The results of the pharmacokinetic study will be published later, as Part II.


Assuntos
Cocaína/análogos & derivados , Cocaína/sangue , Eletroforese Capilar/métodos , Compostos Radiofarmacêuticos/sangue , Animais , Ratos , Padrões de Referência , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
18.
J Chromatogr A ; 885(1-2): 41-9, 2000 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-10941666

RESUMO

A novel experimental method for determining the equilibrium constant, Keq, and the uptake rate constant, kup, for the solid-phase extraction (SPE) of diuron from water using a C18 Empore extraction disk is reported. Log Keq and log kup are determined at 7.0, 11.0, 18.0 and 23.0 degrees C and for stirring rates of 100, 200 and 400 rpm. From a Van 't Hoff plot of log Keq versus T-1 the enthalpy of sorption, delta H0, is shown to be negative which indicates that the thermodynamic process of uptake is exothermic. The rate of stirring has no effect on log Keq over the temperature range 7.0-23.0 degrees C. The enthalpy of activation, delta H0, calculated from Arrhenius plots of log kup versus T-1 at 100, 200 and 400 rpm show that the kinetic process of uptake is endothermic. At 100 rpm the rate of uptake is limited by the aqueous diffusion of diuron. At 200 rpm or greater the aqueous diffusion layer around the disk is sufficiently small to prevent diffusion from being a limiting factor. The method described in this paper is limited to the analysis of analytes that contain a significant UV chromophore and are relatively soluble in water, but it can also be used to investigate pH and salinity effects on the SPE of diuron from water.


Assuntos
Cromatografia Líquida/instrumentação , Diurona/isolamento & purificação , Água/química , Espectrofotometria Ultravioleta , Temperatura , Termodinâmica
19.
Radiographics ; 20(4): 1073-103; quiz 1110-1, 1112, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10903697

RESUMO

Primary cardiac and pericardial neoplasms are rare lesions and include both benign and malignant histologic types. Myxoma is the most frequent primary cardiac neoplasm, but other benign tumors include papillary fibroelastoma, rhabdomyoma, fibroma, hemangioma, lipoma, and paraganglioma. Cardiac sarcoma represents the second most common primary cardiac neoplasm. Lymphoma can also affect the heart primarily. Pericardial tumors that affect the heart include benign teratomas and malignant mesotheliomas. Patients affected with cardiac or pericardial neoplasms often present with cardiovascular compromise or embolic phenomena and exhibit cardiomegaly at chest radiography. Benign cardiac tumors typically manifest as intracavitary, mural, or epicardial focal masses, whereas malignant tumors demonstrate invasive features and may involve the heart diffusely. Benign lesions can usually be successfully excised, but patients with malignant lesions have an extremely poor prognosis.


Assuntos
Diagnóstico por Imagem , Neoplasias Cardíacas/diagnóstico , Pericárdio/patologia , Fibroma/diagnóstico , Fibroma/patologia , Neoplasias Cardíacas/patologia , Hemangioma/diagnóstico , Hemangioma/patologia , Humanos , Lipoma/diagnóstico , Lipoma/patologia , Linfoma/diagnóstico , Linfoma/patologia , Mesotelioma/diagnóstico , Mesotelioma/patologia , Mixoma/diagnóstico , Mixoma/patologia , Invasividade Neoplásica , Paraganglioma/diagnóstico , Paraganglioma/patologia , Prognóstico , Rabdomioma/diagnóstico , Rabdomioma/patologia , Sarcoma/diagnóstico , Sarcoma/patologia , Teratoma/diagnóstico , Teratoma/patologia
20.
Pharm Res ; 17(4): 419-26, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10870985

RESUMO

PURPOSE: To quantitatively predict the in vivo interaction between triazolam and erythromycin, which involves mechanism-based inhibition of CYP3A4, from in vitro studies using human liver microsomes (HLM) and recombinant human CYP3A4 (REC). METHODS: HLM or REC was preincubated with erythromycin in the presence of NADPH and then triazolam was added. alpha- and 4-hydroxy (OH) triazolam were quantified after a 3 min incubation and the kinetic parameters for enzyme inactivation (k(inact) and K('app)) were obtained. Drug-drug interaction in vivo was predicted based on a physiologically-based pharmacokinetic (PBPK) model, using triazolam and erythromycin pharmacokinetic parameters obtained from the literature and kinetic parameters for the enzyme inactivation obtained in the in vitro studies. RESULTS: Whichever enzyme was used, triazolam metabolism was not inhibited without preincubation, even if the erythromycin concentration was increased. The degree of inhibition depended on preincubation time and erythromycin concentration. The values obtained for k(inact) and K('app) were 0.062 min(-1) and 15.9 microM (alpha-OH, HLM), 0.055 min(-1) and 17.4 microM (4-OH, HLM), 0.173 min(-1) and 19.1 microM (alpha-OH, REC), and 0.097 min(-1) and 18.9 microM (4-OH, REC). Based on the kinetic parameters obtained using HLM and REC, the AUCpo of triazolam was predicted to increase 2.0- and 2.6-fold, respectively, following oral administration of erythromycin (333 mg t.i.d. for 3 days), which agreed well with the reported data. CONCLUSIONS: In vivo interaction between triazolam and erythromycin was successfully predicted from in vitro data based on a PBPK model involving a mechanism-based inhibition of CYP3A4.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Eritromicina/farmacologia , Microssomos Hepáticos/enzimologia , Oxigenases de Função Mista/metabolismo , Triazolam/farmacologia , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Citocromo P-450 CYP3A , Inibidores das Enzimas do Citocromo P-450 , Interações Medicamentosas , Humanos , Oxigenases de Função Mista/antagonistas & inibidores , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Triazolam/antagonistas & inibidores
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