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1.
Infection ; 49(2): 313-320, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33387261

RESUMO

PURPOSE: This study aimed to determine the proportion of people living with HIV with anti-SARS-CoV-2 IgG antibodies in a sample from a large single HIV center in Munich, Germany, after the first phase of the coronavirus pandemic and to infer the prevalence of SARS-CoV-2 co-infection in people living with HIV. METHODS: Prospective sub-study of the ongoing ArcHIV cohort between May and July 2020. Anti-SARS-CoV-2 IgG antibodies were measured using the recomWell SARS-CoV-2 IgG ELISA (Mikrogen, Neuried, Germany); positive and borderline results were re-tested using the recomLine SARS-CoV-2 IgG immunoassay (Mikrogen, Neuried, Germany). Demographic and medical data were extracted from the electronic patient files. RESULTS: Overall, 500 people living with HIV were included in the study (83% male, median age 51 years). Three participants had been diagnosed with COVID-19 prior to study inclusion. Of those, nine were confirmed positive for SARS-CoV-2 IgG antibodies, resulting in an estimated seroprevalence (accounting for sensitivity and specificity of the test) of 1.5% (CI 95%: 0.69; 3.13) for the entire study sample, and 2.2% (CI 95%: 1.1; 3.9) for the subset of the Munich citizens. There were no marked differences for people living with HIV with and without SARS-CoV-2 co-infection. CONCLUSION: The seroprevalence of SARS-CoV-2 co-infection in people living with HIV as found in our study does not seem to exceed previous reports from general populations of 'hot-sport' areas; comparative data from the Munich population can be expected to be published soon. Our data also highlight, once more, the need to do confirmatory testing on positive samples to minimize the impact of false-positive results.


Assuntos
COVID-19/epidemiologia , Coinfecção/epidemiologia , Hotspot de Doença , Infecções por HIV/epidemiologia , Adulto , Anticorpos Antivirais/sangue , COVID-19/diagnóstico , Coinfecção/diagnóstico , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Alemanha/epidemiologia , Infecções por HIV/diagnóstico , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade , Estudos Soroepidemiológicos
2.
Platelets ; 31(6): 756-762, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-31608753

RESUMO

Cardiovascular disease is an important contributor to morbidity and mortality in people living with HIV . The immature platelet fraction (IPF) is increased in HIV-negative patients with cardiovascular disease and evidence suggests that an enlarged IPF is associated with adverse cardiovascular events. In this multi-center observational study, we aimed to investigate how the IPF in people living with HIV is influenced by antiretroviral therapy and cardiovascular disease. Subjects without cardiovascular disease that received antiretroviral therapy showed a smaller IPF accompanied by lower D-dimer and C-reactive protein (CRP) levels compared to therapy-naïve subjects (mean IPF: 2.9% vs. 3.9%, p = .016; median D-dimer: 252 µg/L vs. 623 µg/L, p < .001; median CRP: 0.2 mg/dL vs. 0.5 mg/dL, p = .004). No significant differences for the IPF, D-dimer or CRP were found between subjects on antiretroviral therapy with documented cardiovascular disease and therapy-naïve subjects. In conclusion, we observed a reduction in the IPF among subjects on therapy only in the absence of cardiovascular disease. In contrast, subjects receiving therapy that had documented cardiovascular disease showed an IPF comparable to therapy-naïve subjects. Future studies are needed to investigate if an enlarged IPF may serve as a biomarker in predicting adverse cardiovascular events in people living with HIV.


Assuntos
Antirretrovirais/uso terapêutico , Plaquetas/metabolismo , Doenças Cardiovasculares/sangue , Infecções por HIV/sangue , Adulto , Antirretrovirais/farmacologia , Plaquetas/efeitos dos fármacos , Plaquetas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
5.
Sci Total Environ ; 912: 169087, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38056641

RESUMO

Climate change is driving compositional shifts in ecological communities directly by affecting species and indirectly through changes in species interactions. For example, competitive hierarchies can be inversed when competitive dominants are more susceptible to climate change. The brown seaweed Fucus vesiculosus is a foundation species in the Baltic Sea, experiencing novel interactions with the invasive red seaweed Gracilaria vermiculophylla, which is known for its high tolerance to environmental stress. We investigated the direct and interactive effects of warming and co-occurrence of the two algal species on their performance, by applying four climate change-relevant temperature scenarios: 1) cooling ) 2 °C below ambient - representing past conditions), 2) ambient summer temperature (18 °C), 3) IPCC RCP2.6 warming scenario (1 °C above ambient), and 4) RCP8.5 warming (3 °C above ambient) for 30 days and two compositional levels (mono and co-cultured algae) in a fully-crossed design. The RCP8.5 warming scenario increased photosynthesis, respiration, and nutrients' uptake rates of mono- and co-cultured G. vermiculophylla while growth was reduced. An increase in photosynthesis and essential nutrients' uptake and, at the same time, a growth reduction might result from increasing stress and energy demand of G. vermiculophylla under warming. In contrast, the growth of mono-cultured F. vesiculosus significantly increased in the highest warming treatment (+3 °C). The cooling treatment (-2 °C) exerted a slight negative effect only on co-cultured F. vesiculosus photosynthesis, compared to the ambient treatment. Interestingly, at ambient and warming (RCP2.6 and RCP8.5 scenarios) treatments, both F. vesiculosus and G. vermiculophylla appear to benefit from the presence of each other. Our results suggest that short exposure of F. vesiculosus to moderate or severe global warming scenarios may not directly affect or even slightly enhance its performance, while G. vermiculophylla net performance (growth) could be directly hampered by warming.


Assuntos
Fucus , Gracilaria , Alga Marinha , Aquecimento Global , Mudança Climática , Temperatura
6.
Int Endod J ; 45(6): 542-51, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22264187

RESUMO

AIM: To evaluate morphological changes to the major foramen after overinstrumentation with ProTaper Universal and ProFile Vortex Ni-Ti rotary instruments. METHODOLOGY: Twenty-eight mesiobuccal canals of maxillary and mandibular first molars were divided into two groups of 14 canals each. The root canals were prepared with ProTaper Universal or ProFile Vortex instruments. ProTaper and Vortex instruments were used until the file tip protruded 1 mm beyond the working length (0.5 mm beyond the major foramen). The major foramen was photographed before and after overinstrumentation with each file of the two systems used. The images were superimposed and evaluated using Adobe Photoshop. The parameters evaluated were canal transportation, centring ability and shape of the major foramen. Transportation and centring ability were calculated in two directions: the direction of maximum curvature (MC) and a direction vertical to the maximum curvature (VC). Measurements of canal transportation and centring ability were analysed by anova followed by post hoc least significance difference (LSD) multiple comparisons. RESULTS: No significant differences were observed amongst the different instruments with respect to centring ability in either direction (P > 0.05). The F3 ProTaper Universal instrument was associated with a higher mean values for transportation in the direction of MC (P < 0.05) than the S1, S2 and F1 ProTaper Universal instruments and the size 15, 0.06 taper, size 20, 0.06 taper, and size 25, 0.06 taper ProFile Vortex instruments. The size 30, 0.06 taper ProFile Vortex instrument had a larger mean value for transportation in the direction of MC (P < 0.05) than the S1 ProTaper Universal and size 15, 0.06 taper ProFile Vortex instruments. The S1, S2, F1, F2 and F3 ProTaper Universal files and the size 15, 0.06 taper, size 20, 0.06 taper, size 25, 0.06 taper, and size 30, 0.06 taper ProFile Vortex files produced an oval foramen in 71%, 71%, 85%, 85%, 71%, 71%, 85%, 85% and 89% of the cases, respectively. CONCLUSIONS: In most samples, the ProTaper Universal and ProFile Vortex files produced transportation of the major foramen and created an oval-shaped major foramen after overinstrumentation.


Assuntos
Cavidade Pulpar/ultraestrutura , Preparo de Canal Radicular/instrumentação , Dentina/ultraestrutura , Desenho de Equipamento , Humanos , Processamento de Imagem Assistida por Computador/métodos , Teste de Materiais , Dente Molar/ultraestrutura , Odontometria/métodos , Radiografia Dentária Digital/métodos , Preparo de Canal Radicular/normas , Ápice Dentário/ultraestrutura
7.
Int J STD AIDS ; 30(5): 447-452, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30630396

RESUMO

Hyperparathyroidism has been described in people living with HIV undergoing tenofovir disoproxil fumarate (TDF)-containing antiretroviral therapy (ART), but differences in calcium levels have never been investigated in detail. We aimed to compare the prevalence of hypocalcemia between patients with and without TDF-containing ART. The patients and methods were a retrospective cohort study in HIV-infected adult patients receiving dolutegravir and either abacavir (ABC)/lamivudine (3TC) or TDF/emtricitabine in a single center in Munich, Germany. Of 172 patients, 126 (73.3%) were male and the median age was 48.5 years (interquartile range 42-54). Average calcium levels were 2.24 (2.21-2.29) mmol/l and 2.21 (2.16-2.26) mmol/l (P < 0.001) with a prevalence of at least one episode of total calcium <2.12 mmol/l of 16.2 and 34.4% in the groups treated with ABC/3TC and TDF/emtricitabine, respectively (P = 0.006). TDF use was independently associated with the occurrence of albumin-corrected calcium levels of <2.12 mmol/l (odds ratio: 6.7 [1.3-35.6]; P = 0.025). Hypocalcemia seems to occur more often in TDF-treated patients. Further research into hypocalcemia with TDF and potential cardiovascular effects may be of benefit based on these findings.


Assuntos
Fármacos Anti-HIV/efeitos adversos , Terapia Antirretroviral de Alta Atividade/métodos , Didesoxinucleosídeos/efeitos adversos , Infecções por HIV/tratamento farmacológico , Inibidores de Integrase de HIV/efeitos adversos , Compostos Heterocíclicos com 3 Anéis/efeitos adversos , Hipocalcemia/induzido quimicamente , Lamivudina/efeitos adversos , Tenofovir/efeitos adversos , Adulto , Fármacos Anti-HIV/uso terapêutico , Cálcio/sangue , Estudos de Coortes , Didesoxinucleosídeos/uso terapêutico , Combinação de Medicamentos , Feminino , Infecções por HIV/virologia , Inibidores de Integrase de HIV/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Humanos , Hipocalcemia/diagnóstico , Hipocalcemia/epidemiologia , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oxazinas , Piperazinas , Prevalência , Piridonas , Estudos Retrospectivos , Tenofovir/uso terapêutico , Resultado do Tratamento
8.
Plant Biol (Stuttg) ; 10(1): 163-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18211554

RESUMO

Research on biogenic volatile organic compound (BVOC) emissions has mainly focused on native species in natural ecosystems. However, much of the ozone and aerosol formation occurs in city atmospheres due to BVOC emissions by local urban vegetation. Plant composition of urban habitats is often dominated by non-native ornamental plant species, for which only limited data on BVOC emissions are available. To gain insight into the influence of ornamental vegetation on the urban atmospheric reactivity in Barcelona, Spain, we studied volatile isoprenoid emissions in 11 widespread ornamental tree species (three conifers and nine angiosperms). We found significant monoterpene emissions in all studied species, with normalized emission potentials (T=30 degrees C, photosynthetic photon flux density (PPFD)=1000 micromol x m(-2) x s(-1)) ranging between 0.2 to 110 microg x g(-1) (dry weight) h(-1). Depending on species, the emissions were dominated by alpha- and beta-pinene, myrcene, alpha- and beta-phellandrene, carene, limonene and eucalyptol. These data demonstrate that ornamental plants may significantly contribute to the BVOC load in urban atmospheres and also underscore the importance of broadleaf angiosperms as significant monoterpene emitters.


Assuntos
Cidades , Monoterpenos/metabolismo , Árvores/metabolismo , Poluentes Atmosféricos/metabolismo , Transpiração Vegetal , Espanha
9.
Plant Biol (Stuttg) ; 10(1): 129-37, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17564947

RESUMO

Monoterpenes synthesized and released by emitting vegetation can be taken up by neighboring non-emitting plants, but the uptake capacity of non-emitting species has not been studied extensively. We investigated the foliar uptake potential of the hydrophobic monoterpene limonene in 13 species of contrasting leaf structure and lipid content to determine the structural and chemical controls of monoterpene uptake. Leaf dry mass per unit area (M(A,D)) varied 6.5-fold, dry to fresh mass ratio (D(F)) 2.7-fold, lipid content per dry mass (L(M)) 2.5-fold and per unit area (L(A)) 4.6-fold across the studied species. Average foliar limonene uptake rate (U(A)) from air at saturating limonene partial pressures varied from 0.9 to 6 nmol m(-2) s(-1), and limonene leaf to air partition coefficient (K(FA), ratio of limonene content per dry mass to limonene partial pressure) from 0.7 to 6.8 micromol kg(-1) Pa(-1). U(A) and K(FA) scaled positively with leaf lipid content, and were independent of D(F), indicating that variation in leaf lipid content was the primary determinant of species differences in monoterpene uptake rate and K(FA). Mass-based limonene uptake rates further suggested that thinner leaves with greater surface area per unit dry mass have higher uptake rates. In addition, limonene lipid to air partition coefficient (K(LA)=K(FA)/L(M)) varied 19-fold, indicating large differences in limonene uptake capacity at common leaf lipid content. We suggest that the significant uptake of hydrophobic monoterpenes when monoterpene ambient air concentration is high and release when the concentration is low should be included in large-scale monoterpene emission models.


Assuntos
Cicloexenos/metabolismo , Lipídeos/química , Magnoliopsida/química , Magnoliopsida/metabolismo , Monoterpenos/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Terpenos/metabolismo , Limoneno , Monoterpenos/química
10.
Int J STD AIDS ; 29(11): 1136-1139, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29749880

RESUMO

We present the case of a 58-year-old HIV-infected patient with adrenal insufficiency after local injection of triamcinolone, most likely due to drug-drug interaction with his ritonavir-boosted antiretroviral therapy (ART). This is the first case of adrenal insufficiency occurring without prior symptoms of Cushing's syndrome in a patient on a booster-containing ART. We want to draw attention to this seemingly rare, but potentially life-threatening medical condition that can occur even in short-term use of glucocorticoids in low doses in patients on booster-containing ART and summarize some considerations for management.


Assuntos
Insuficiência Adrenal/induzido quimicamente , Terapia Antirretroviral de Alta Atividade , Interações Medicamentosas , Glucocorticoides/administração & dosagem , Infecções por HIV/tratamento farmacológico , Dor Lombar/tratamento farmacológico , Ritonavir/uso terapêutico , Triancinolona/administração & dosagem , Glucocorticoides/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Triancinolona/efeitos adversos
11.
J Neuroimmunol ; 110(1-2): 161-7, 2000 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-11024546

RESUMO

The expression and function of cannabinoid receptor 1 (CB1) in mouse immune cells is unclear. Here we show that splenic B cells express more CB1 mRNA than T cells. Furthermore, splenocytes stimulated with the T cell mitogens, PMA/Io and anti-CD3, showed a decrease in CB1 message while cultures stimulated with the B cell mitogen, anti-CD40 antibody, showed an increase in message. In addition, co-treatment with mitogens and IL-2 uniformly caused an increase in CB1 mRNA. It is suggested that signaling pathways activated by T cell mitogens lead to decreased CB1 gene activation while pathways activated by B cell mitogens and IL-2 lead to increased CB1.


Assuntos
Complexo CD3/imunologia , Antígenos CD40/imunologia , Interleucina-2/farmacologia , Receptores de Droga/genética , Animais , Anticorpos/farmacologia , Linfócitos B/química , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Carcinógenos/farmacologia , Feminino , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/imunologia , Interleucina-2/imunologia , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/análise , Receptores de Canabinoides , Receptores de Droga/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Baço/citologia , Baço/imunologia , Acetato de Tetradecanoilforbol/farmacologia
12.
Sleep ; 17(8): 693-702, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7701180

RESUMO

We compared three measures of daytime sleepiness, sleep behavior (as measured by the multiple sleep latency test), a biological index of sleepiness (pupillometry) and subjective sleepiness (as measured by the Stanford Sleepiness Scale), in evaluating middle-aged individuals with psychophysiological insomnia (n = 20) or no sleep problem (n = 20). Subjects underwent polysomnography (PSG) and four multiple sleep latency test/pupillometry trials the following day. The results determined that neither behavioral, biological nor subjective indices distinguished these two groups. Differentiating the insomniacs into true insomniac (n = 14) and normal sleeping insomniac (insomniacs with sleep efficiency greater than 90%, n = 6) subgroups based upon PSG did not improve daytime discriminations. Furthermore, nighttime sleep experience, measured by either PSG or self-report, was not a strong predictor of these daytime indices among either insomniacs or noninsomniacs. The results of this study support the conclusions that insomniacs do not exhibit heightened levels of daytime sleepiness and that routine fluctuations in sleep exert minimal influence on daytime sleepiness among insomniacs and noninsomniacs. The former finding is likely due either to insomniacs satisfying their biological sleep need despite poor sleep or chronic physiological hyperarousal preventing both sleep and sleepiness.


Assuntos
Narcolepsia/diagnóstico , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Adulto , Eletromiografia , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Reflexo Pupilar , Sono REM
13.
Sleep ; 20(12): 1151-6, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9493925

RESUMO

The relationship between a new operational definition of sleep sounds and apnea was examined in a population of 69 patients referred for overnight evaluations in a sleep disorders center. The sample contained 18 women (mean age 53.6 years) and 51 men (mean age 48.4 years). Subjects underwent polysomnography (PSG) with concurrent graphical recording of sleep sound intensities throughout the night. An acoustical signature event (ASE) was defined as a loud sound preceded by at least 10 but no more than 90 seconds of silence. Multiple regression was performed using known correlates of apnea and ASE to predict PSG levels of respiratory disturbance. Of the commonly known correlates, only self-reported estimate of snoring and apnea severity explained significant variance to the respiratory disturbance index (RDI; R2 = 0.24, p < 0.0001). ASE was entered into the equation as the last step, significantly improving explained variance (R2delta = 0.54, p < 0.0001). The final equation R2 was 78% (p < 0.0001). An alternative analysis compared ASE findings to polysomnographic findings in each matched 30-second interval (60,231 observations) in an analysis of receiver's operating characteristics. This analysis resulted in d' = 2.67, indicating acceptable accuracy for screening.


Assuntos
Síndromes da Apneia do Sono/complicações , Síndromes da Apneia do Sono/diagnóstico , Ronco/etiologia , Adulto , Índice de Massa Corporal , Eletroencefalografia , Eletromiografia , Eletroculografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oximetria , Polissonografia , Valor Preditivo dos Testes , Índice de Gravidade de Doença
14.
Chest ; 115(6): 1621-6, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10378559

RESUMO

BACKGROUND: The diagnosis of viable myocardium in the setting of ischemic left ventricular systolic dysfunction might indicate which patients have the greatest prognostic benefit from myocardial revascularization. Single-photon emission CT (SPECT) thallium-201 (201Tl) scintigraphy for the detection of viable myocardium is widely available in the community, but outcome data using this imaging modality are limited. METHODS: Thirty-seven patients (mean [+/- SD] age, 62+/-12 years) with ischemic left ventricular dysfunction (mean ejection fraction, 30+/-9%) initially referred for rest-redistribution SPECT thallium scintigraphy were evaluated 29+/-19 months after coronary bypass surgery (n = 15) or medical therapy alone (n = 22). The relationship among myocardial viability, mode of therapy, and long-term prognosis was evaluated. RESULTS: Significant myocardial viability (defined as a viability index [VI] of > 0.5) was present in 19 patients. Among patients with a VI > 0.5, the 48-month actuarial event-free survival was 89+/-10% for patients undergoing surgical revascularization, compared with 0% for the medical treatment subgroup (p = 0.005). In contrast, patients in the low-viability subgroup tended to have intermediate event-free survival rates, which were not statistically different for patients receiving either surgical (62+/-21%) or medical therapy (50+/-14%; p = 0.55). CONCLUSIONS: Survival is significantly more favorable for surgically revascularized patients with ischemic left ventricular dysfunction and myocardial viability as detected by SPECT 201Tl scintigraphy.


Assuntos
Coração/diagnóstico por imagem , Isquemia Miocárdica/diagnóstico por imagem , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão de Fóton Único , Disfunção Ventricular Esquerda/diagnóstico por imagem , Repouso em Cama , Intervalo Livre de Doença , Eletrocardiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Isquemia Miocárdica/mortalidade , Isquemia Miocárdica/cirurgia , Revascularização Miocárdica , Prognóstico , Estudos Retrospectivos , Volume Sistólico , Taxa de Sobrevida , Disfunção Ventricular Esquerda/mortalidade , Disfunção Ventricular Esquerda/cirurgia
15.
Behav Res Ther ; 35(8): 733-40, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9256516

RESUMO

Fatigue has often been confused with sleepiness and has received little study as an independent symptom of sleep disturbance. To investigate if fatigue is a common and severe symptom in sleep disordered individuals, the Fatigue Severity Scale (FSS) was administered to 206 patients over a 12-month period at a sleep disorder center. Our sample averaged 4.8 on the 7-point FSS, which is in the severe fatigue range. High fatigue was present in a broad range of sleep disorders, but was particularly high among individuals diagnosed with psychophysiological insomnia. A number of variables predicted fatigue (being female, being a smoker, high BMI, low sleep efficiency percent, and high MMPI average clinical scale score), but surprisingly daytime sleepiness (as measured by the multiple sleep latency test) did not. Apparently, daytime sleepiness and perceived fatigue are independent phenomena. We discussed the importance of attributing credence to the complaint of fatigue and suggested some areas for future study including further study of fatigue in insomnia, expanded consideration of sleep variables causing fatigue, and testing objective measures of fatigue.


Assuntos
Fadiga/epidemiologia , Transtornos do Sono-Vigília/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
16.
J Pharm Biomed Anal ; 18(4-5): 911-8, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9919997

RESUMO

Separation buffers for the determination of the corticosteroids cortisone, hydrocortisone, prednisone and prednisolone with micellar electrokinetic chromatography were developed with respect to separation efficacy and the migration times, depending on the type and the concentration of the organic modifier acetonitrile as well as on the addition of gamma-cyclodextrin. The buffer containing 50 mM SDS and 16% (v/v) acetonitrile enables the rapid profiling of prednisolone together with cortisone and prednisone. Addition of gamma-cyclodextrin alters the elution sequence, but does not further enhance resolution of the corticosteroids. Baseline separation at long migration times for cortisone, hydrocortisone, prednisone and prednisolone is achieved with a buffer containing 50 mM each of SDS, dehydrocholic acid sodium salt and glycodeoxycholic acid sodium salt.


Assuntos
Corticosteroides/análise , Cromatografia Capilar Eletrocinética Micelar/métodos , Acetonitrilas , Ácidos e Sais Biliares , Soluções Tampão , Micelas , Modelos Químicos , Dodecilsulfato de Sódio
17.
Adv Exp Med Biol ; 493: 215-21, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11727768

RESUMO

There is significant evidence that cannabinoids have the ability to exert immunomodulatory effects. The identification of cannabinoid receptors in immune tissues has therefore led to questions about whether these immunomodulatory effects occur via these cannabinoid receptors. The cannabinoid receptor 1 (CB 1), although expressed primarily in the brain, is also expressed in lower amounts in peripheral tissues. Of interest to us is the fact that CB1 is expressed in immune tissues such as spleen, albeit at lower levels than the peripheral cannabinoid receptor, CB2. To examine the function of CBI in immune cells, activation experiments were performed using different stimuli e.g., anti-CD3, phorbol 12-myristate 13-acetate (PMA)/Ionomycin (Io), and PMA/Io + IL-2. Whole spleen cells were cultured in the presence of different stimuli for 0, 2, 4, and 24 hours, harvested at each time point, RNA isolated, and RT-PCR performed. FACS analysis was also performed using CD69 (an early activation marker) to determine whether cells were actually being activated. Results from anti-CD3 stimulation indicated a decrease in CB1 mRNA expression following activation. CB1 mRNA expression in murine splenocytes that were stimulated with PMA/Io in the presence or absence of IL-2 was also modulated. Expression of the message was enhanced upon stimulation with PMA/Io and PMA/Io + IL-2, however, stimulation with PMA/Io + IL-2 led to a stronger increase within 2 to 4 hours with CB1 returning to at or below baseline levels by 24 hours. Expression of CD69 was detected in all stimulated samples thereby indicating that the splenocytes were becoming activated. In summary, anti-CD3 stimulation appeared to decrease CB1 mRNA expression while PMA/Io + IL-2 stimulation significantly increased CB1 mRNA expression. These results demonstrate that the expression of CB1 mRNA is modulated upon cellular activation and that this modulation is dependent on the stimulus that is used.


Assuntos
RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Droga/genética , Baço/imunologia , Baço/metabolismo , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Sequência de Bases , Feminino , Expressão Gênica/efeitos dos fármacos , Interleucina-2/farmacologia , Ionomicina/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Receptores de Canabinoides , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
18.
Adv Exp Med Biol ; 437: 223-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9666275

RESUMO

Marijuana and other drugs have been suggested to act as cofactors for HIV infection. Interestingly, delta 9-THC has been shown to upregulate NF kappa B, a transcription factor utilized by HIV. Therefore, it was of interest to investigate whether cannabinoids can modulate HIV infection and replication. Initially, we tested for evidence of receptor expression by examining for receptor mRNA in various cell lines used to study HIV infection and replication. Cellular RNA was isolated from SupT, and H9, H9MN, and MT-2 cells and RT-PCR was performed. Results showed that, although all of the cell lines tested were positive for CB2 mRNA, only the MT-2 cells also expressed CBI mRNA. Since the MT-2 cells expressed both CBI and CB2 receptor mRNA, we next wanted to determine whether different cannabinoid receptor agonists such as CP-55,940, delta 9-THC, WIN-55,212-2, and WIN-55,212-3 influenced infection of these cells by cell free HIV-1MN. Infectivity assays were performed where MT-2 cells were incubated with drug and cell free virus for 90 min, the free virus washed off, and the cells incubated further, and checked for virus growth by syncytia formation. It was found that the drugs significantly increased syncytia formation when MT-2 cells were cultured in the presence of both drug and cell free HIV-1MN. In conclusion, of the cell lines tested, only the MT-2 cells were positive for both CB1 and CB2 mRNA. In addition, since syncytia formation is an indication of virus infection and cytopathicity it was concluded that cannabimimetic drugs may enhance HIV-1 infection of susceptible cells.


Assuntos
Dronabinol/farmacologia , HIV-1/fisiologia , Receptores de Droga/fisiologia , Linhagem Celular , Células Gigantes/efeitos dos fármacos , Células Gigantes/virologia , Receptores de Canabinoides , Receptores de Droga/agonistas , Receptores de Droga/metabolismo
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