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1.
Ann Oncol ; 31(8): 1040-1045, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32387456

RESUMO

BACKGROUND: Cell entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) depends on binding of the viral spike (S) proteins to angiotensin-converting enzyme 2 and on S protein priming by TMPRSS2. Inhibition of TMPRSS2 may work to block or decrease the severity of SARS-CoV-2 infections. Intriguingly, TMPRSS2 is an androgen-regulated gene that is up-regulated in prostate cancer where it supports tumor progression and is involved in a frequent genetic translocation with the ERG gene. First- or second-generation androgen-deprivation therapies (ADTs) decrease the levels of TMPRSS2. Here we put forward the hypothesis that ADTs may protect patients affected by prostate cancer from SARS-CoV-2 infections. MATERIALS AND METHODS: We extracted data regarding 9280 patients (4532 males) with laboratory-confirmed SARS-CoV-2 infection from 68 hospitals in Veneto, one of the Italian regions that was most affected by the coronavirus disease 2019 (COVID-19) pandemic. The parameters used for each COVID-19-positive patient were sex, hospitalization, admission to intensive care unit, death, tumor diagnosis, prostate cancer diagnosis, and ADT. RESULTS: There were evaluable 9280 SARS-CoV-2-positive patients in Veneto on 1 April 2020. Overall, males developed more severe complications, were more frequently hospitalized, and had a worse clinical outcome than females. Considering only the Veneto male population (2.4 million men), 0.2% and 0.3% of non-cancer and cancer patients, respectively, tested positive for SARS-CoV-2. Comparing the total number of SARS-CoV-2-positive cases, prostate cancer patients receiving ADT had a significantly lower risk of SARS-CoV-2 infection compared with patients who did not receive ADT (OR 4.05; 95% CI 1.55-10.59). A greater difference was found comparing prostate cancer patients receiving ADT with patients with any other type of cancer (OR 4.86; 95% CI 1.88-12.56). CONCLUSION: Our data suggest that cancer patients have an increased risk of SARS-CoV-2 infections compared with non-cancer patients. However, prostate cancer patients receiving ADT appear to be partially protected from SARS-CoV-2 infections.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vigilância da População , Neoplasias da Próstata/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , COVID-19 , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/epidemiologia , Fatores de Risco , SARS-CoV-2
2.
Gynecol Endocrinol ; 35(10): 894-898, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31081709

RESUMO

Several studies have compared the effectiveness of corifollitropin alfa versus daily gonadotropins in poor ovarian responders (PORs) undergoing controlled ovarian stimulation (COS), showing conflicting results in terms of IVF outcomes. Given the heterogeneity of patients included in the classification of POR according to 'Bologna criteria', the aim of this study was to evaluate the impact of corifollitropin alfa in two different categories of POR distinguished according to patients' antral follicle count (AFC). We retrospectively evaluated 104 infertile POR, split into two groups according to AFC (Group A ≤ 5; Group B > 5) and subgroups according to the ovarian stimulation regimen (corifollitropin alfa plus daily gonadotropins (Subgroup 1) versus daily gonadotropins alone (Subgroup 2)). Outcome measures were total oocytes, MII oocytes, total embryos, follicular output rate (FORT), implantation rate (IR), clinical pregnancy rate (CPR), miscarriage rate (MR), and live birth rate (LBR). Subgroup A1 experienced a lower number of total oocytes, MII oocytes, total embryos, and FORT (p < .05) in comparison to Subgroup A2, while no difference was found when comparing Subgroups B1 and B2. No difference was found between subgroups even in terms of IR, CPR, MR, and LBR. In conclusion, corifollitropin alfa may be as effective as daily gonadotropins in POR with AFC > 5 undergoing COS, while it might be inferior to daily gonadotropins in POR with AFC ≤ 5.


Assuntos
Coeficiente de Natalidade , Hormônio Foliculoestimulante Humano/administração & dosagem , Indução da Ovulação/métodos , Taxa de Gravidez , Adulto , Feminino , Fertilização in vitro/métodos , Humanos , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos , Resultado do Tratamento
3.
Gynecol Endocrinol ; 34(9): 752-755, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29463152

RESUMO

The influence of thyroid autoimmunity in assisted reproductive technology (ART) outcome in euthyroid women is still controversial. In this study, we retrospectively evaluated embryo quality in 123 euthyroid women undergoing ART with or without thyroid autoantibodies (TAA). Embryo quality was assessed in 119 embryos of 29 infertile patients with TAA and in 394 embryos of 94 infertile patients without TAA. Our results showed not statistically significant differences in age, body mass index, anti-Müllerian hormone, follicle stimulating hormone, free triiodothyronine, and free thyroxine levels between cases and controls. Thyroid stimulating hormone was within the normal range, but significantly higher in TAA patients compared with the controls (2.4 ± 0.8 vs. 2 ± 0.9 mIU/L, respectively, p < .01). The number of oocytes picked up and fertilized was comparable between the two groups. Embryo quality was significantly impaired in women with at least one autoantibody (p < .001). Implantation rate, pregnancy rate, and ongoing pregnancy rate were comparable in the two groups. These results suggest a negative impact of thyroid autoimmunity in embryo quality in women undergoing ART even when thyroid function is normal.


Assuntos
Autoanticorpos/sangue , Autoimunidade/fisiologia , Implantação do Embrião/fisiologia , Infertilidade Feminina/terapia , Técnicas de Reprodução Assistida , Glândula Tireoide/imunologia , Fatores Etários , Hormônio Antimülleriano/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Infertilidade Feminina/sangue , Infertilidade Feminina/imunologia , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Tiroxina/sangue , Tri-Iodotironina/sangue
4.
J Endocrinol Invest ; 39(9): 1015-21, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27072668

RESUMO

PURPOSE: Spironolactone (SP) is an effective treatment for polycystic ovary syndrome (PCOS), but it is often associated with menstrual abnormalities whose mechanism is still under investigation. In this study, we investigated the serum sex steroids and endometrial thickness in 30 PCOS patients, before and after one-month 100 mg SP treatment. METHODS: Serum FSH, LH, estradiol, progesterone and endometrial thickness were evaluated at the 14th and 16th day of the menstrual cycle, before and during short-term SP treatment. According to the presence (15 cases) or absence (15 cases) of menstrual bleeding at the 14th day during SP, the patients were divided into two groups, which were then compared using a two-tailed Student's t test. RESULTS: Serum estradiol and endometrial thickness were lower than pretreatment at both determinations in all patients, but patients with bleeding had significantly lower estradiol values than non-bleeding ones, both before and after therapy. Endometrial thickness was significantly lower in the bleeding group compared with non-bleeding group only at the 16th day of the cycle. These differences were significant, even though the values of estradiol and endometrial thickness remained in the normal range. CONCLUSIONS: SP therapy can reduce the values of estradiol and the endometrial thickness in patients with PCOS compared with pretreatment, but PCOS patients with bleeding had pretreatment estradiol values lower than the patients who did not complain of this side effect. Intermenstrual abnormalities may represent the low estrogen impregnation of endometrium due to SP, whose mechanism is complex, involving several factors, such as the effects of some metabolites of SP on estradiol and progesterone production, on their receptors, and the individual metabolism of SP in vivo.


Assuntos
Índice de Massa Corporal , Ciclo Menstrual/efeitos dos fármacos , Metrorragia/induzido quimicamente , Antagonistas de Receptores de Mineralocorticoides/efeitos adversos , Síndrome do Ovário Policístico/tratamento farmacológico , Espironolactona/efeitos adversos , Adulto , Feminino , Humanos , Ultrassonografia , Adulto Jovem
5.
Nutr Metab Cardiovasc Dis ; 25(4): 418-25, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25636381

RESUMO

BACKGROUND AND AIMS: ApoA-I can undergo oxidative changes that reduce anti-atherogenic role of HDL. The aim of this study was to seek any significant differences in methionine sulfoxide (MetO) content in the ApoA-I of HDL isolated from young patients with coronary heart disease (CHD), type 2 diabetics and healthy subjects. METHODS AND RESULTS: We evaluated the lipid profile of 21 type 2 diabetic patients, 23 young patients with premature MI and 21 healthy volunteers; we determined in all patients the MetO content of ApoA-I in by MALDI/TOF/TOF technique. The typical MALDI spectra of the tryptic digest obtained from HDL plasma fractions all patients showed a relative abundance of peptides containing Met(112)O in ApoA-I in type 2 diabetic and CHD patients. This relative abundance is given as percentages of oxidized ApoA-I (OxApoA-I). OxApoA-I showed no significant correlations with lipoproteins in all patients studied, while a strong correlation emerged between the duration of diabetic disease and OxApoA-I levels in type 2 diabetic patients. CONCLUSIONS: The most remarkable finding of our study lies in the evidence it produced of an increased HDL oxidation in patients highly susceptible to CHD. Levels of MetO residues in plasma ApoA-I, measured using an accurate, specific method, should be investigated and considered in prospective future studies to assess their role in CHD.


Assuntos
HDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Infarto do Miocárdio/sangue , Adulto , Apolipoproteína A-I/sangue , LDL-Colesterol/sangue , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Metionina/análogos & derivados , Metionina/metabolismo , Pessoa de Meia-Idade , Estresse Oxidativo , Fatores de Risco , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
6.
Diabet Med ; 28(9): 1074-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21658125

RESUMO

AIMS: The International Association of the Diabetes and Pregnancy Study Groups (IADPSG) Consensus Panel recommends new criteria for diagnosing gestational diabetes. We evaluated the clinical and metabolic characteristics, and pregnancy outcome, in women previously classifiable as 'normal' according to the 4th International Workshop Conference on gestational diabetes criteria, but reclassified as 'abnormal' according to the new recommendations. METHODS: Using the new IADPSG criteria, 3953 pregnancies were retrospectively reclassified as 1815 women with normal glucose tolerance and 2138 with gestational diabetes, 112 (2.8%) of whom would have been classified as normal according to the older criteria. RESULTS: Of the 2138 women classified as abnormal by the new criteria, the 112 women now reclassified as abnormal were younger and had a lower pre-pregnancy BMI than the 2026 women who had also been classified as abnormal by the previous criteria. The 100-g oral glucose tolerance test showed significantly higher glucose levels in these 112 women than in the 1815 women reclassified as normal (P < 0.0001). Caesarean section was significantly more frequent (P < 0.01) and the ponderal index for the newborn significantly higher in these reclassified women than in those classified as normal (P < 0.0001), and their basal glucose levels correlated significantly with the ponderal index (P < 0.05). CONCLUSION: The new criteria for diagnosing gestational diabetes identified a group of women previously classifiable as normal according to the 4th International Workshop Conference criteria, but revealing metabolic characteristics and pregnancy outcomes resembling those of women who would have been considered to have gestational diabetes by the previous criteria.


Assuntos
Glicemia/metabolismo , Diabetes Gestacional/epidemiologia , Hemoglobinas Glicadas/metabolismo , Adulto , Análise de Variância , Diabetes Gestacional/classificação , Diabetes Gestacional/diagnóstico , Feminino , Teste de Tolerância a Glucose , Humanos , Recém-Nascido , Guias de Prática Clínica como Assunto , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Medição de Risco
7.
Diabetologia ; 52(7): 1419-25, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19401824

RESUMO

AIMS/HYPOTHESIS: This study examined the relationship, if any, between glucose-induced oxidative stress, antioxidant status and microalbuminuria in patients with type 2 diabetes. METHODS: The study involved 99 consecutive type 2 diabetic patients (57 men, 42 women). Patients with persistent microalbuminuria were identified and the following variables evaluated: fasting plasma glucose, HbA(1c), malonyldialdehyde (MDA), pentosidine, AGE, the total radical-trapping antioxidant parameter (TRAP), vitamin E, creatinine, estimated GFR and lipid profile. RESULTS: Patients were divided into two groups, i.e. 37 individuals without microalbuminuria (AER <20 microg/min) and 62 with microalbuminuria (AER > or =20 microg/min). The following variables were significantly higher in patients with microalbuminuria than in those without microalbuminuria (mean +/- SD): fasting plasma glucose 9.41 +/- 2.88 vs 8.19 +/- 1.93 mmol/l, p < 0.05; HbA(1c) 7.97 +/- 1.51 vs 7.39 +/- 1.03%, p < 0.05; MDA 1.18 +/- 0.35 vs 1.02 +/- 0.29 micromol/l, p < 0.05; pentosidine 98.5 +/- 24.6 vs 82.9 +/- 20.9 pmol/ml, p < 0.005; and AGE 13.2 +/- 4.8 vs 10.6 +/- 3.8 microg/mg protein, p < 0.01. However, vitamin E and TRAP did not differ between the two groups. Serum creatinine values and estimated GFR were similar in the two groups. Only in patients with microalbuminuria were significant linear correlations seen between AER and both oxidation (HbA(1c) r = 0.33, p < 0.01; MDA r = 0.59, p < 0.001; pentosidine r = 0.48, p < 0.001; and AGE r = 0.44, p < 0.001) and antioxidation variables (vitamin E r = -0.55, p < 0.001; TRAP r = -0.49, p < 0.001). Considering all variables together, multiple regression revealed a correlation between microalbuminuria and vitamin E, TRAP, HbA(1c) and MDA, but not pentosidine or AGE. CONCLUSIONS/INTERPRETATION: Our data suggest that microalbuminuria in type 2 diabetic patients might be promoted by an insufficient counter-regulation of the antioxidant system in the event of increased glyco-oxidation/glycation.


Assuntos
Albuminúria/metabolismo , Antioxidantes/metabolismo , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Estresse Oxidativo/fisiologia , Idoso , Nefropatias Diabéticas/metabolismo , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Oxirredução
8.
J Endocrinol Invest ; 32(11): 895-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19509473

RESUMO

Clinical studies have demonstrated that aldosterone receptor antagonists do improve the survival of patients with chronic heart diseases and in vitro studies have shown that canrenone blocks the proinflammatory effect of aldosterone in mononucler leukocytes (MNL). The aim of the study was to compare, in the model of human MNL, the effect of potassium-sparing diuretics amiloride and canrenone, on the protein expression of p22phox, a NADPH-oxidase system subunit, that is a principal marker of production of superoxide anions. MNL were isolated from 10 informed healthy volunteers (5 males and 5 females, age range 24-36 yr) and the proteins extracted. p22phox protein expression was evaluated by Western blot and quantified using a densitometric semiquantitative analysis. The experiments showed that aldosterone (10(-8) M) enhances the protein expression of p22phox and that its effect is reversed by co-incubation with canrenone (10(-6) M), while incubation with amiloride (10(-6) M) reduced the prooxidative effect of aldosterone at a significantly lower extent than canrenone. Co-incubation with canrenone, amiloride, and aldosterone together produced the same effect as aldosterone plus canrenone. Incubation with cortisol (40(-8) M) was not effective. These data confirm the prooxidative effect of aldosterone in MNL. The addition of aldosterone-receptor antagonist canrenone produced a higher inhibition than sodium channel blocker amiloride on the effect of aldosterone on p22phox protein expression.


Assuntos
Aldosterona/farmacologia , Amilorida/farmacologia , Canrenona/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , NADPH Oxidases/biossíntese , Adulto , Feminino , Humanos , Hidrocortisona/farmacologia , Leucócitos Mononucleares/metabolismo , Masculino , Antagonistas de Receptores de Mineralocorticoides/farmacologia , NADPH Oxidases/efeitos dos fármacos , Bloqueadores dos Canais de Sódio/farmacologia
9.
Urol Int ; 81(1): 94-100, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18645279

RESUMO

INTRODUCTION: Normal and abnormal bladder contractions are principally mediated by acetylcholine released from postganglionic parasympathetic nerves. Since amikacin was reported to affect neurotransmission by a prejunctional mechanism, we investigated the effect of amikacin on isolated detrusor smooth muscle contraction to further evaluate its potential relaxant properties. MATERIALS AND METHODS: Detrusor smooth muscle obtained from 15 rats and 8 patients undergoing surgery were studied through measurement of isometric muscular contraction induced with electrical field stimulation (EFS) (10-60 Hz), carbachol (10(-7) to 10(-3)M) and nicotine (10(-7) to 10(-3)M) in the presence or absence of 1 mM amikacin in a low-Ca medium. RESULTS: Amikacin (1 mM) significantly reduced EFS-induced contraction of isolated rat and human detrusor muscle by 33 +/- 6.57% (p < 0.005) and 40 +/- 1.14% (p < 0.001), respectively. Contraction was restored after addition of calcium chloride (1 mM). The effect of amikacin was comparable to that of magnesium ions. Rat and human detrusor contractile response to nicotine was inhibited by 70 +/- 8.27% (p < 0.001) and 64 +/- 14.09% (p < 0.01) after the addition of amikacin (1 mM), while no significant effect was observed on carbachol-induced stimulation. CONCLUSION: Amikacin significantly inhibited detrusor contraction evoked by prejunctional stimulation in vitro, suggesting a depressant effect on autonomic neurotransmission in urinary bladder.


Assuntos
Amicacina/farmacologia , Antibacterianos/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/patologia , Bexiga Urinária/efeitos dos fármacos , Animais , Cloreto de Cálcio/metabolismo , Carbacol/metabolismo , Relação Dose-Resposta a Droga , Humanos , Técnicas In Vitro , Masculino , Neurotransmissores/metabolismo , Nicotina/metabolismo , Ratos , Ratos Wistar , Bexiga Urinária/inervação
10.
Neurogastroenterol Motil ; 19(8): 668-74, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17640182

RESUMO

A protective role of the transient potential vanilloid receptor 1 (TRPV1) in intestinal inflammation induced by dinitrobenzene sulphonic acid (DNBS) has been recently demonstrated. Curcumin, the major active component of turmeric, is also able to prevent and ameliorate the severity of the damage in DNBS-induced colitis. We evaluated the possibility that curcumin (45 mg kg(-1) day p.o. for 2 days before and 5 days after the induction of colitis) was able to reduce DNBS-induced colitis in mice, by acting as a TRPV1 agonist. Macroscopic damage score, histological damage score and colonic myeloperoxidase (MPO) activity were significantly lower (by 71%, 65% and 73%, respectively; P < 0.01), in animals treated with curcumin compared with untreated animals. Capsazepine (30 mg kg(-1), i.p.), a TRPV1 receptor antagonist, completely abolished the protective effects of curcumin. To extend these data in vitro, Xenopus oocytes expressing rat TRPV1 were examined. Capsaicin-evoked currents (3.3 micromol L(-1)) disappeared subsequent either to removal of the agonist or subsequent to the addition of capsazepine. However, curcumin (30 micromol L(-1)) was ineffective both as regard direct modification of cell membrane currents and as regard interference with capsaicin-mediated effects. As sensitization of the TRPV1 receptor by mediators of inflammation in damaged tissues has been shown previously, our results suggest that in inflamed, but not in normal tissue, curcumin can interact with the TRPV1 receptor to mediate its protective action in DNBS-induced colitis.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Colite/tratamento farmacológico , Colite/fisiopatologia , Curcumina/farmacologia , Canais de Cátion TRPV/fisiologia , Animais , Benzenossulfonatos , Capsaicina/análogos & derivados , Capsaicina/farmacologia , Membrana Celular/fisiologia , Colite/induzido quimicamente , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Oócitos/fisiologia , Peroxidase/metabolismo , Índice de Gravidade de Doença , Canais de Cátion TRPV/antagonistas & inibidores , Xenopus
11.
Acta Diabetol ; 54(1): 45-51, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27638302

RESUMO

AIMS: Analyze plasma phospholipid fatty acids (PPFA) composition and desaturase activity in women with gestational diabetes (GDM) and in women with a normal glucose tolerance (NGT) before and after delivery, and to evaluate the possible relationship between desaturase activity and inflammatory parameters. METHODS: PPFA composition was analyzed by gas chromatography in 21 women with GDM and from 21 with NGT, during the third trimester of pregnancy and 6 months after delivery. We used fatty acid product-to-precursor ratios to estimate desaturase activity, and we also measured in all women interleukins six and ten, tumor necrosis factor alpha and C-reactive protein. RESULTS: No significant differences were observed between NGT and GDM women in terms of PPFA composition, both in pregnancy and after pregnancy. Estimated desaturase Δ9-18 activity was significantly higher, and estimated desaturase Δ5 activity was significantly lower during pregnancy in all women. We observed no correlations between inflammatory markers and desaturases activity, during or after pregnancy, in both groups. CONCLUSIONS: Our data suggest that GDM does not influence PPFA composition and desaturase activity during pregnancy. In addition, late pregnancy characterized by hyperinsulinemia appears to upregulate desaturase Δ9-18 activity in NGT and GDM women.


Assuntos
Diabetes Gestacional/sangue , Ácidos Graxos Dessaturases/sangue , Ácidos Graxos/sangue , Fosfolipídeos/sangue , Adulto , Proteína C-Reativa , Colesterol/sangue , Citocinas/sangue , Registros de Dieta , Feminino , Teste de Tolerância a Glucose , Humanos , Inflamação/sangue , Gravidez , Terceiro Trimestre da Gravidez
12.
J Mass Spectrom ; 41(12): 1534-45, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17051519

RESUMO

The standardization and quality control of plant extracts is an important topic, in particular, when such extracts are used for medicinal purposes. Consequently, the development of fast and effective analytical methods for metabolomic fingerprinting of plant extracts is of high interest. In this investigation, electrospray mass spectrometry (ESI-MS) and (1)H NMR techniques were employed with further statistical analyses of the acquired data. The results showed that negative ion mode ESI-MS is particularly effective for characterization of plant extracts. Different samples of the same species appear well-clustered and separated from the other species. To verify the effectiveness of the method, two other batches of extracts from a species, in which the principal components were already identified (Cynara scolymus), were analyzed, and the components that were verified by the principal component analysis (PCA) were found to be within the region identified as characteristic of Cynara Scolymus extracts. The data from extracts of the other species were well separated from those pertaining to the species previously characterized. Only the case of a species that was strictly correlated from a botanical point of view, with extracts that were previously analyzed, showed overlapping.


Assuntos
Ressonância Magnética Nuclear Biomolecular/métodos , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Achillea/química , Cimicifuga/química , Análise por Conglomerados , Cynara scolymus/química , Filipendula/química , Helianthus/química , Análise Multivariada , Prótons , Salvia officinalis/química
14.
Geobiology ; 14(4): 364-73, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27027519

RESUMO

During the past two decades, a plethora of fossil micro-organisms have been described from various Triassic to Miocene ambers. However, in addition to entrapped microbes, ambers commonly contain microscopic inclusions that sometimes resemble amoebae, ciliates, microfungi, and unicellular algae in size and shape, but do not provide further diagnostic features thereof. For a better assessment of the actual fossil record of unicellular eukaryotes in amber, we studied equivalent inclusions in modern resin of the Araucariaceae; this conifer family comprises important amber-producers in Earth history. Using time-of-flight secondary ion mass spectrometry (ToF-SIMS), we investigated the chemical nature of the inclusion matter and the resin matrix. Whereas the matrix, as expected, showed a more hydrocarbon/aromatic-dominated composition, the inclusions contain abundant salt ions and polar organics. However, the absence of signals characteristic for cellular biomass, namely distinctive proteinaceous amino acids and lipid moieties, indicates that the inclusions do not contain microbial cellular matter but salts and hydrophilic organic substances that probably derived from the plant itself. Rather than representing protists or their remains, these microbe-like inclusions, for which we propose the term 'pseudoinclusions', consist of compounds that are immiscible with the terpenoid resin matrix and were probably secreted in small amounts together with the actual resin by the plant tissue. Consequently, reports of protists from amber that are only based on the similarity of the overall shape and size to extant taxa, but do not provide relevant features at light-microscopical and ultrastructural level, cannot be accepted as unambiguous fossil evidence for these particular groups.


Assuntos
Âmbar/química , Eucariotos/química , Fósseis , Espectrometria de Massa de Íon Secundário , Árvores
15.
Biochim Biophys Acta ; 1527(3): 167-75, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11479034

RESUMO

The following enzyme activities of the tryptophan-nicotinic acid pathway were studied in male New Zealand rabbits: liver tryptophan 2,3-dioxygenase, intestine indole 2,3-dioxygenase, liver and kidney kynurenine 3-monooxygenase, kynureninase, kynurenine-oxoglutarate transaminase, 3-hydroxyanthranilate 3,4-dioxygenase, and aminocarboxymuconate-semialdehyde decarboxylase. Intestine superoxide dismutase and serum tryptophan were also determined. Liver tryptophan 2,3-dioxygenase exists only as holoenzyme, but intestine indole 2,3-dioxygenase is very active and can be considered the key enzyme which determines how much tryptophan enters the kynurenine pathway also under physiological conditions. The elevated activity of indole 2,3-dioxygenase in the rabbit intestine could be related to the low activity of superoxide dismutase found in intestine. Kynurenine 3-monooxygenase appeared more active than kynurenine-oxoglutarate transaminase and kynureninase, suggesting that perhaps a major portion of kynurenine available from tryptophan may be metabolized to give 3-hydroxyanthranilic acid, the precursor of nicotinic acid. In fact, 3-hydroxyanthranilate 3,4-dioxygenase is much more active than the other previous enzymes of the kynurenine pathway. In the rabbit liver 3-hydroxyanthranilate 3,4-dioxygenase and aminocarboxymuconate-semialdehyde decarboxylase show similar activities, but in the kidney 3-hydroxyanthranilate 3,4-dioxygenase activity is almost double. These data suggest that in rabbit tryptophan is mainly metabolized along the kynurenine pathway. Therefore, the rabbit can also be a suitable model for studying tryptophan metabolism in pathological conditions.


Assuntos
Dioxigenases , Intestinos/enzimologia , Rim/enzimologia , Cinurenina/metabolismo , Fígado/enzimologia , Triptofano/metabolismo , 3-Hidroxiantranilato 3,4-Dioxigenase , Animais , Carboxiliases/análise , Hidrolases/análise , Indolamina-Pirrol 2,3,-Dioxigenase , Quinurenina 3-Mono-Oxigenase , Masculino , Oxigenases de Função Mista/análise , Modelos Químicos , Niacina/metabolismo , Oxigenases/análise , Ácidos Picolínicos/metabolismo , Coelhos , Triptofano/sangue , Triptofano Oxigenase/análise
16.
Ann N Y Acad Sci ; 1043: 217-24, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16037242

RESUMO

Advanced glycation end products (AGEs) accumulate in serum and tissues of patients with chronic renal failure, even in the absence of diabetes, and a different clearance of these species has been observed by hemodialysis and peritoneal dialysis (CAPD). Furthermore, it has been shown that not only AGE but also 1,2-dicarbonyl compounds are formed during heat sterilization of glucose-based peritoneal dialysis fluids. Therefore, we investigated the level of some AGEs (pentosidine and free pentosidine) and dicarbonyl compounds (glyoxal and methylglyoxal) in end-stage renal disease patients subjected to peritoneal dialysis. Samples (20 from healthy subjects, 16 from uremic patients before and after 12 h of peritoneal dialysis) were analyzed, and the plasma and dialysate levels of glyoxal, methylglyoxal, pentosidine, and free pentosidine were determined. In plasma of uremic patients, mean values of pentosidine showed a small decrease after dialysis and were always higher than those of healthy control subjects. An analogous trend was observed for free pentosidine. In the case of peritoneal dialysate, no pentosidine and free pentosidine were found at time zero, whereas both compounds were detected after 12 h of dialysis. Glyoxal and methylglyoxal mean levels showed a decrease in plasma after dialysis even if their values were always higher than those of healthy control subjects. Surprisingly, an analogous trend was observed also in dialysate. These results might indicate that glyoxal and methylglyoxal already present in the dialysis fluid react with the peritoneal matrix proteins, accounting for the gradual loss of peritoneal membrane function that is often observed in patients subjected to CAPD for a long time.


Assuntos
Glioxal/sangue , Falência Renal Crônica/sangue , Aldeído Pirúvico/sangue , Uremia/sangue , Idoso , Proteínas Sanguíneas/análise , Feminino , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Diálise Peritoneal Ambulatorial Contínua , Uremia/terapia
17.
Pharmazie ; 60(12): 910-6, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16398267

RESUMO

The aim of the present study was to design a test to ascertain the behaviour and reliability of a membrane used in drug release and simulated absorption tests in order to arrive at useful indications for simulating topical as well as gastro-intestinal absorption. The membrane can be used in two different conditions: a) as a simple porous membrane placed between the ointment and an accepting liquid phase, generally water phase; b) as a membrane soaked in a lipophilic liquid phase to simulate the horny layer between the ointment and accepting water phase. In this study the "bubble point test" was used to test the integrity of the soaking film as well as the membrane, during and after drug release and simulated absorption tests with different types of ointment. In the case of a drug release test from an ointment, the bubble point test may determine the test conditions, that is the ointment applied to either a dry or hydrated membrane. Only the use of a previously hydrated membrane can guarantee constant conditions in the in vitro model. Use of a dry membrane may lead to infiltration of liquid components of the ointment base, thus altering the contact conditions between the two phases of the cutaneous compartment model (lipogel and W/O creams). The use of a hydrated membrane may also lead to interactions between the two phases of the compartment, with osmotic exchanges between the acceptor phase and ointment sample (hydrogel, PEG gel, O/W creams). The hydrated membrane is therefore reliable only for comparison between lipophilic base ointments. In a simulated absorption test, determination of the bubble point makes it possible to ascertain the physical integrity of the lipoid liquid film immobilized by capillary action in the inner microporous structure of the membrane during the test. This condition is essential to maintain a balance between the parameters regulating the diffusion process between the different compartments of the system. The use of a lipoid-soaked membrane makes it possible to avoid interactions between the ointment sample and an aqueous acceptor phase, such as hydrosoluble bases. Since the diffusion across a lipoid film immobilised within a porous membrane depends on the drug release rate from the ointment base, the test allows a contextual evaluation of the release kinetics as well as an indication of the drug absorption possibilities through an in vitro model of the cutaneous compartment.


Assuntos
Pomadas/normas , Algoritmos , Anestésicos Locais/administração & dosagem , Anestésicos Locais/química , Área Sob a Curva , Benzocaína/administração & dosagem , Benzocaína/química , Química Farmacêutica , Excipientes , Filtração , Cinética , Membranas Artificiais , Modelos Químicos , Bases para Pomadas , Porosidade , Absorção Cutânea
18.
Exp Hematol ; 28(7): 775-83, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10907639

RESUMO

OBJECTIVE: Transforming growth factor beta3 (TGF-beta3) is a potent suppressor of human hematopoietic progenitor cells. In this article, we compare the activity of TGF-beta3 on highly purified CD34+ cells and more immature CD34-DR(-) cells from chronic myelogenous leukemia (CML) patients in chronic phase and normal donors. MATERIALS AND METHODS: Primitive hematopoietic progenitors were stimulated in liquid cultures and clonogenic assays by early-acting growth factors such as stem cell factor (SCF) and interleukin 11 (IL-11) and the intermediate-late-acting stimulating factors IL-3, granulocyte-macrophage colony-stimulating factor, and erythropoietin. Molecular analysis of bcr/abl mRNA was performed on single CML colonies by nested reverse transcriptase polymerase chain reaction. Moreover, cell cycle analysis and assessment of apoptosis of normal and leukemic CD34+ cells were performed by propidium iodide (PI) alone and simultaneous staining with annexin V and PI, respectively. RESULTS: The colony-forming efficiency of CML CD34+ cells was generally inhibited by more than 90% regardless of whether the colony-stimulating factors were used alone or combined. When compared to normal CD34+ cells, leukemic cells were significantly more suppressed in 6 of 8 culture conditions. The inhibitory effect of TGF-beta3 on CD34+ cells was exerted within the first 24 hours of incubation as demonstrated by short-term preincubation followed by IL-3-and SCF-stimulated colony assays. Evaluation of bcr/abl transcript on residual CML colonies incubated with TGF-beta3 demonstrated a small subset of neoplastic CD34+ cells unresponsive to the inhibitory effect of the study cytokine. TGF-beta3 demonstrated a greater inhibitory activity on primitive CD34+DR cells than on more mature CD34+ cells. Again, CML CD34+DR(-) cells were significantly more inhibited by TGF-beta3 than their normal counterparts in 3 of 8 culture conditions. Kinetic analysis performed on CD34+ cells showed that TGF-beta induces cell cycle arrest in G(1) phase. However, this mechanism of action is shared by normal and leukemic cells. Conversely, TGF-beta3 preferentially triggered the programmed cell death of CML CD34-cells without increasing the proportion of leukemic cells coexpressing CD95 (Fas receptor), and this effect was not reversed by functional blockade of Fas receptor. Conclusion. We demonstrate that TGF-beta3 exerts a potent suppressive effect on CML cells that is partly mediated by Fas-independent apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Hematopoese/efeitos dos fármacos , Leucemia Mielogênica Crônica BCR-ABL Positiva/fisiopatologia , Fator de Crescimento Transformador beta/farmacologia , Receptor fas/fisiologia , Antígenos CD34/análise , Ciclo Celular , Células Cultivadas , Células Clonais/metabolismo , Citocinas/farmacologia , Humanos , Regulação para Cima
19.
Atherosclerosis ; 106(1): 51-63, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8018107

RESUMO

In this study we have considered the possibility of inducing vascular damage in Yoshida Pittsburg (YOS) rat, an inbred strain which has endogenous hyperlipidemia without vascular atherosclerotic damage. Cholesterol-enriched diet (4% cholesterol plus 1% cholic acid and 0.5% thiouracil) was administered to YOS rats, in order to induce atherogenesis. The results indicate that, despite significant increase in serum (about 2-fold) and aortic tissue cholesterol (about 6-fold), no morphological damage occurred. A reduction in acetylcholine-mediated relaxation (of about 37%) was observed. No inhibition of ATP- or sodium nitrite-induced relaxation, or of contraction induced by norepinephrine was seen. Serum triglyceride concentration did not vary after administration of a cholesterol-enriched diet. Our results suggest that in heritable hyperlipidemic Yoshida rat, after 2 months of cholesterol-enriched diet, despite increased serum cholesterol levels, no atheromatous plaque developed on the aortic wall. Impaired vascular function and reductions in the response to acetylcholine were related to changed endothelial cell function. Administration of a high cholesterol diet to YOS rat may represent a new model of mixed endogenous and exogenous hyperlipidemia that can resemble many human dislipidemic diseases and therefore may become a useful tool for the study of isolated endothelial dysfunction.


Assuntos
Aorta Torácica/fisiopatologia , Colesterol na Dieta/efeitos adversos , Hiperlipidemias/fisiopatologia , Acetilcolina/farmacologia , Trifosfato de Adenosina/farmacologia , Animais , Aorta Torácica/metabolismo , Aorta Torácica/patologia , Arteriosclerose/etiologia , Colesterol/sangue , Colesterol/metabolismo , Colesterol na Dieta/administração & dosagem , Hiperlipidemias/complicações , Hiperlipidemias/patologia , Masculino , Norepinefrina/farmacologia , Ratos , Ratos Endogâmicos , Nitrito de Sódio/farmacologia , Triglicerídeos/sangue , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
20.
Atherosclerosis ; 89(2-3): 223-30, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1793450

RESUMO

Serum and aortic tissue cholesterol levels in parallel with aortic relaxation to endothelium-dependent and independent drugs were determined in Watanabe heritable hyperlipidemic (WHHL) rabbits in comparison with New Zealand (N.Z.) normocholesterolemic rabbits, aged 4-14 months. Serum cholesterol was elevated (626 +/- 99 mg/100 ml) in 4-6-month-old WHHL rabbits and significantly lower in 12-14-month-old animals (344 +/- 51 mg/100 ml). Cholesterol infiltration in thoracic aorta was high in young WHHL compared with N.Z. rabbits (0.88 +/- 0.3 mg/100 mg fresh tissue vs. 0.08 +/- 0.003 mg/100 mg, respectively) and it did not vary with age. In N.Z. rabbits, serum and aortic cholesterol levels were low from 4 to 14 months of age. The aortic relaxation to acetylcholine (0.03-3 microM) on EC50 noradrenaline precontracted rings was similar in 4-6-month-old WHHL and N.Z. rabbits of the same age. In WHHL rabbits, the relaxation to acetylcholine was significantly reduced in 7-11- (-35% at maximum) and in 12-14-month-old rabbits (-40% at maximum). In N.Z. rabbits the response to acetylcholine was not modified in the 3 age groups. The relaxation to ATP (30 microM to 3 mM) was reduced by age both in N.Z. and in WHHL rabbits, but in 12-14-month-old WHHL rabbits the maximal relaxing response was significantly more elevated than in age-matched N.Z. rabbits (50.1 +/- 2.5% vs. 35.1 +/- 3.2%, respectively). The aortic relaxation to NaNO2 (10 microM to 3 mM) was reduced by age both in N.Z. and in WHHL rabbits.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Aorta Torácica/fisiopatologia , Hiperlipidemias/fisiopatologia , Relaxamento Muscular/efeitos dos fármacos , Acetilcolina/farmacologia , Trifosfato de Adenosina/farmacologia , Fatores Etários , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Colesterol/sangue , Colesterol/metabolismo , Feminino , Hiperlipidemias/sangue , Hiperlipidemias/genética , Técnicas In Vitro , Masculino , Norepinefrina/farmacologia , Coelhos , Nitrito de Sódio/farmacologia , Triglicerídeos/sangue
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