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1.
Eur J Clin Microbiol Infect Dis ; 36(1): 43-48, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27638008

RESUMO

The influence of contraception on vaginal microflora can have a major impact on the risk of developing acute or recurrent vaginal infections, but also may influence the risk of acquiring sexually transmissible infections (STI) such as HIV. A cohort of 248 women presenting for levonorgestrel-releasing intrauterine system (LNG-IUS) insertion or reinsertion were stratified according to their current contraceptive method. Information concerning their menstrual pattern and data about the medical history were collected. The composition of their vaginal microflora was studied by detailed phase contrast microscopy of fresh vaginal fluid, and aerobic cultures were taken to detect enteric bacterial growth and fungal colonisation. LNG-IUS and progesterone-only-pill (POP) users had significantly lower blood loss (p < 0.001) than other women. Regardless of the type of contraception used, all women reported similar rates of symptomatic lower genital tract infection during the preceding year. Women using combined oral contraception (COC) and long-term LNG-IUS had the same bacterial composition of vaginal microflora as non-contraceptive users, even when infections were combined. Both hormonal and non-hormonal intrauterine device users had an increased tendency to have more vaginal colonisation with Candida. Women on POPs or subcutaneous implants had a tendency towards increased vaginal atrophy, but had a lower Candida carriage rate compared to IUCD users (LNG-IUS and Copper-IUCD, p = 0.037). Women with an increased risk of acquiring STIs or recurrent BV could benefit from LNG-IUS or COC due to a well-preserved vaginal bacterial flora. Women with a susceptibility for RVVC should prefer POPs, and avoid intrauterine contraception.


Assuntos
Bactérias/classificação , Anticoncepção/métodos , Anticoncepcionais/administração & dosagem , Fungos/classificação , Microbiota , Vagina/microbiologia , Adulto , Bactérias/isolamento & purificação , Feminino , Fungos/isolamento & purificação , Humanos , Técnicas Microbiológicas , Microscopia de Contraste de Fase , Pessoa de Meia-Idade
2.
Facts Views Vis Obgyn ; 7(4): 257-260, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-27729971

RESUMO

Prevention of progression to invasive carcinoma in patients with a premalignant endometrial lesion using longterm treatment with levonorgestrel (LNG) releasing intrauterine systems (IUS) remains controversial, especially when manifest cellular atypia has been found in the endometrial biopsy specimen. We present a case of a 44-year old premenopausal woman with a premalignant uterine polyp who declined hysterectomy and was followed-up for more than 12 years after the first LNG-IUS was inserted. Endometrial atrophy installed, no pathology was detected and hysterectomy was thereby successfully avoided. The positive experience in this case should encourage further studies as literature data indicate that conservative treatment of premalignant endometrial pathology is a real option with a high success rate for women who have a contra-indication for surgery, refuse the classical approach for personal reasons or want to preserve their fertility.

3.
Eur J Clin Microbiol Infect Dis ; 30(1): 59-63, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20878199

RESUMO

Antibacterial therapy may enhance the risk of symptomatic vulvo-vaginal candidosis in susceptible women. We addressed the question whether oral antifungal treatment for vulvo-vaginal candidosis also influences the bacterial vaginal microflora. One hundred and forty-two patients with a culture-proven acute episode of recurrent vulvo-vaginal candidosis (RVC) were treated with fuconazole according to the ReCiDiF regimen (induction dose of 600 mg orally per week followed by 200 mg per week) or with a single dose of 200 mg pramiconazole, a new potent oral triazole. At inclusion, 1 week and 1 month after the end of antifungal treatment, the bacterial microflora was assessed by microscopy of vaginal fluid to detect lactobacillary grades and bacterial vaginosis (BV). The presence of BV was studied in these patients with vulvo-vaginal candidosis after treatment with antifungal medication. At the start of oral antifungal treatment, 6.3% of women with Candida were co-infected with BV. Of the BV-negative women, 10 out of 133 (8%) developed BV after 1 week and after 1 month 8 of them (7%) were still BV-positive. Although no patients received antibacterial treatment at any moment of the study, 6 out of 9 (66%) of the women with Candida and BV at inclusion no longer had BV 1 week after antifungal treatment and 6 out of 7 (86%) lacked BV after 1 month. Treatment with antifungals may have a beneficial effect on women with concurrent BV, but does not prevent BV from occurring in BV-negative women with Candida vaginitis.


Assuntos
Antifúngicos/uso terapêutico , Bactérias/crescimento & desenvolvimento , Candidíase Vulvovaginal/tratamento farmacológico , Vaginose Bacteriana/induzido quimicamente , Administração Oral , Antifúngicos/administração & dosagem , Feminino , Fluconazol/administração & dosagem , Fluconazol/uso terapêutico , Humanos , Imidazóis/administração & dosagem , Imidazóis/uso terapêutico , Triazóis/administração & dosagem , Triazóis/uso terapêutico
4.
Infect Immun ; 77(5): 2084-93, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19289516

RESUMO

Currently available Neisseria meningitidis serogroup B (MenB) vaccines are based on outer membrane vesicles (OMVs) that are obtained from wild-type strains. They are purified with the aim of decreasing the lipooligosaccharide (LOS) content and hence reduce the reactogenicity of the vaccine even though LOS is a potential protective antigen. In <2-year-old children, these MenB vaccines confer protection only against strains expressing homologous PorA, a major and variable outer membrane protein. Our objective was to develop a safe LOS-based vaccine against MenB. To this end, we used modified porA knockout strains expressing genetically detoxified (msbB gene-deleted) L2 and L3,7 LOSs, allowing the production of LOS-enriched OMVs. The vaccine-induced antibodies were found to be bactericidal against nearly all invasive strains, irrespective of capsular serogroup. In addition, we have also demonstrated that LOS lacking the terminal galactose (with a lgtB mutation; truncated L3 LOS), but not LOS produced without the galE gene, induced a bactericidal antibody response in mice similar to that seen for LOS containing the full lacto-N-neotetraose (L3,7 LOS). In conclusion, a bivalent detoxified LOS OMV-based vaccine demonstrated the potential to afford a broad cross-protection against meningococcal disease.


Assuntos
Anticorpos Antibacterianos/sangue , Lipopolissacarídeos/genética , Lipopolissacarídeos/imunologia , Viabilidade Microbiana , Neisseria meningitidis Sorogrupo B/química , Neisseria meningitidis Sorogrupo B/imunologia , Vesículas Secretórias/imunologia , Animais , Feminino , Técnicas de Inativação de Genes , Camundongos , Porinas/genética
5.
Maturitas ; 57(2): 210-3, 2007 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-17270370

RESUMO

OBJECTIVES: Levonorgestrel (LNG), delivered locally into the uterine cavity has a profound effect on the endometrium. The aim of the study was to use a LNG intrauterine system to treat non-atypical and atypical endometrial hyperplasia in women and to evaluate the long-term cure (remission) rate. METHODS: Each of the 20 women in the study, of whom eight were diagnosed with atypical hyperplasia, received a LNG-IUS, releasing 20 microg LNG/day. The study is a non-comparative study with long-term follow-up (range 14-90 months). RESULTS: All women developed a normal endometrium, except one asymptomatic woman with atypical hyperplasia who still had focal residual non-atypical hyperplasia at 3 years follow-up in the presence of a thin (< 4 mm) endometrium. CONCLUSION: Continuous intrauterine delivery of LNG appears to be a promising alternative to hysterectomy for the treatment of endometrial hyperplasia and could enhance the success rate when compared with other routes of progestagen administration as well as intrauterine progesterone delivery. The significant reduction of the PR expression observed during treatment with the LNG-IUS appears to be a marker for the strong antiproliferative effect of the hormone at a cellular level resulting in an inhibition of estrogen bioactivity and endometrial suppression.


Assuntos
Hiperplasia Endometrial/tratamento farmacológico , Terapia de Reposição de Estrogênios , Dispositivos Intrauterinos Medicados , Levanogestrel/administração & dosagem , Congêneres da Progesterona/administração & dosagem , Adulto , Idoso , Hiperplasia Endometrial/patologia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
6.
Syst Appl Microbiol ; 28(3): 277-86, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15900973

RESUMO

The family Acetobacteraceae currently includes three known nitrogen-fixing species, Gluconacetobacter diazotrophicus, G. johannae and G. azotocaptans. In the present study, acetic acid-producing nitrogen-fixing bacteria were isolated from four different wetland rice varieties cultivated in the state of Tamilnadu, India. Most of these isolates were identified as G. diazotrophicus on the basis of their phenotypic characteristics and PCR assays using specific primers for that species. Based on 16S rDNA partial sequence analysis and DNA: DNA reassociation experiments the remaining isolates were identified as Acetobacter peroxydans, another species of the Acetobacteraceae family, thus far never reported as diazotrophic. The presence of nifH genes in A. peroxydans was confirmed by PCR amplification with nifH specific primers. Scope for the findings: This is the first report of the occurrence and association of N2-fixing Gluconacetobacter diazotrophicus and Acetobacter peroxydans with wetland rice varieties. This is the first report of diazotrophic nature of A. peroxydans.


Assuntos
Acetobacter/isolamento & purificação , Gluconacetobacter/isolamento & purificação , Oryza/microbiologia , Acetobacter/classificação , Acetobacter/genética , Acetobacter/metabolismo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Microbiologia Ambiental , Genes de RNAr , Gluconacetobacter/classificação , Gluconacetobacter/genética , Gluconacetobacter/metabolismo , Índia , Dados de Sequência Molecular , Fixação de Nitrogênio , Hibridização de Ácido Nucleico , Oxirredutases/genética , Filogenia , Reação em Cadeia da Polimerase , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Int J Syst Evol Microbiol ; 54(Pt 2): 551-556, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15023974

RESUMO

Fourteen homofermentative lactic acid bacteria that were isolated from kefir grains and kefir fermented milks were assigned to either Lactobacillus kefiranofaciens or Lactobacillus kefirgranum, based on their characteristic morphotypes, phenotypic features and SDS-PAGE profiles of whole-cell proteins. Further genotypic analyses on representative strains from both taxa demonstrated that L. kefiranofaciens and L. kefirgranum share 100 % 16S rDNA sequence similarity and belong phylogenetically to the Lactobacillus acidophilus species group. DNA-DNA binding values of >79 % and analogous DNA G+C contents of 37-38 mol% showed that the strains studied belonged to one species: L. kefirgranum is a later synonym of L. kefiranofaciens. An emended description is proposed for L. kefiranofaciens. Due to the specific morphological and biochemical characteristics of these taxa in kefir grain formation, it is proposed that L. kefirgranum should be reclassified as L. kefiranofaciens subsp. kefirgranum subsp. nov.


Assuntos
Lactobacillus/classificação , Animais , Sequência de Bases , DNA Bacteriano/genética , DNA Ribossômico/genética , Grão Comestível/microbiologia , Fermentação , Ácido Láctico/metabolismo , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Lactobacillus/fisiologia , Leite/microbiologia , Dados de Sequência Molecular , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética
8.
Int J Syst Evol Microbiol ; 53(Pt 5): 1457-1459, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-13130033

RESUMO

The 16S rDNA sequences of [Aquaspirillum] dispar LMG 4329(T) and Microvirgula aerodenitrificans SGLY2(T) (=LMG 18919(T)) were found to be very similar (>99 %). DNA-DNA hybridizations between the two strains revealed a high level of DNA-DNA binding (84 %), showing that they represent a single species. M. aerodenitrificans and [A.] dispar were also phenotypically very similar. It is concluded that [A.] dispar and M. aerodenitrificans are subjective synonyms. As [A.] dispar was wrongly assigned to the genus Aquaspirillum, we propose that strains of [A.] dispar must be reclassified in the genus MICROVIRGULA: The name Microvirgula aerodenitrificans must be retained for the unified taxon since it is the type of the genus MICROVIRGULA:


Assuntos
Neisseriaceae/classificação , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/análise , Dados de Sequência Molecular , Neisseriaceae/genética , Neisseriaceae/metabolismo , Fenótipo , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Terminologia como Assunto
9.
Int J Syst Evol Microbiol ; 52(Pt 5): 1551-1558, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12361257

RESUMO

Thirty-four Acetobacter strains, representing Acetobacter aceti, Acetobacter pasteurianus, Acetobacter pomorum, Acetobacter peroxydans, Acetobacter lovaniensis, Acetobacter estunensis, Acetobacter orleanensis, Acetobacter indonesiensis and Acetobacter tropicalis, were subjected to a polyphasic study that included DNA-DNA hybridizations, DNA base ratio determinations, 16S rDNA sequence analysis and phenotypic characterization. Two novel species are proposed, Acetobacter cerevisiae sp. nov. and Acetobacter malorum sp. nov. The type strains of these species are respectively LMG 1625T (= DSM 14362T = NCIB 8894T = ATCC 23765T) and LMG 1746T (= DSM 14337T).


Assuntos
Acetobacter/classificação , Acetobacter/genética , Acetobacter/isolamento & purificação , Acetobacter/metabolismo , Composição de Bases , Sequência de Bases , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/genética , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fenótipo , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Especificidade da Espécie , Terminologia como Assunto
10.
Eur J Contracept Reprod Health Care ; 7(1): 24-30, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12041861

RESUMO

OBJECTIVE: To evaluate the return to fertility following removal of the GyneFix intrauterine implant system in women wishing to conceive. STUDY DESIGN: A retrospective study was performed on a sample of healthy, sexually active nulligravid/nulliparous and parous women. The participants were 18-41 years of age, with no apparent infertility problem, living in a stable relationship and planning to become pregnant. Women who changed their mind and did not wish to become pregnant immediately after intrauterine device (IUD) removal were excluded from the study. Women were evaluated in terms of rates of conception and fertility outcome. A total of 128 women were evaluated. RESULTS: The study shows that 119 out of 128 (93%) past users of GyneFix have conceived, accounting for a net cumulative pregnancy rate of 88% at 12 months and 99% after 2 years' observation. No statistical differences in pregnancy rates were found for age and duration of use of the IUD. A strong significant difference in pregnancy rate was shown (p = 0.007) between parous and nulligravid/nulliparous women. Seventy-seven women (66.9%) gave birth to a term infant. There were no stillbirths. Twenty-five women (21.8%) are pregnant at the time of writing. Five (4.4%) spontaneous abortions occurred and in eight women (6.9%) the pregnancy was terminated. There were no ectopic pregnancies. CONCLUSION: The results obtained compare favorably with those obtained in previous studies conducted following the removal of copper IUDs. The use of the frameless IUD does not affect future fertility in nulligravid/nulliparous and parous women wishing to become pregnant following removal of the device. Nulliparous women conceive significantly earlier than parous women.


Assuntos
Fertilidade , Dispositivos Intrauterinos , Paridade , Resultado da Gravidez/epidemiologia , Taxa de Gravidez , Aborto Induzido/estatística & dados numéricos , Aborto Espontâneo/epidemiologia , Aborto Espontâneo/etiologia , Adolescente , Adulto , Bélgica/epidemiologia , Parto Obstétrico/métodos , Parto Obstétrico/estatística & dados numéricos , Desenho de Equipamento , Feminino , Humanos , Recém-Nascido , Dispositivos Intrauterinos/efeitos adversos , Dispositivos Intrauterinos/estatística & dados numéricos , Masculino , Menstruação , Gravidez , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
11.
Int J Syst Evol Microbiol ; 51(Pt 5): 1773-1782, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11594608

RESUMO

Thirty-one heavy-metal-resistant bacteria isolated from industrial biotopes were subjected to polyphasic characterization, including 16S rDNA sequence analysis, DNA-DNA hybridizations, biochemical tests, whole-cell protein and fatty-acid analyses. All strains were shown to belong to the Ralstonia branch of the beta-Proteobacteria. Whole-cell protein profiles and DNA-DNA hybridizations revealed two clearly distinct groups, showing low similarity to known Ralstonia species. These two groups, of 8 and 17 isolates, were assigned to two new species, for which the names Ralstonia campinensis sp. nov. and Ralstonia metallidurans sp. nov. are proposed. The type strains are WS2T (= LMG 19282T = CCUG 44526T) and CH34T (= LMG 1195T = DSM 2839T), respectively. Six isolates were allocated to Ralstonia basilensis, which presently contains only the type strain; an emendation of the latter species description is therefore proposed.


Assuntos
Betaproteobacteria/classificação , Betaproteobacteria/efeitos dos fármacos , Farmacorresistência Bacteriana , Microbiologia Industrial , Metais Pesados/farmacologia , Proteínas de Bactérias/química , Composição de Bases , Betaproteobacteria/metabolismo , DNA Ribossômico/análise , Eletroforese em Gel de Poliacrilamida , Ácidos Graxos/análise , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fenótipo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
12.
Acta Crystallogr D Biol Crystallogr ; 57(Pt 8): 1164-6, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11468407

RESUMO

OpcA is an integral outer membrane from the Gram-negative pathogen Neisseria meningitidis that plays a role in adhesion of meningococci to host cells. The protein was overexpressed in Escherichia coli in an insoluble form and a procedure developed for refolding by rapid dilution from denaturant into detergent solution. The refolded material was identical to native OpcA isolated from meningococci, as judged by overall molecular weight, migration on SDS-PAGE and reaction against monoclonal antibodies. Both native and recombinant OpcA crystallized under similar conditions to give an orthorhombic crystal form (P2(1)2(1)2), with unit-cell parameters a = 96.9, b = 46.3, c = 74.0 A. Complete data sets of reflections were collected from native and refolded OpcA to 2.0 A resolution.


Assuntos
Proteínas de Bactérias/química , Neisseria meningitidis/química , Proteínas de Bactérias/biossíntese , Clonagem Molecular , Cristalização , Cristalografia por Raios X , Conformação Proteica , Dobramento de Proteína
13.
Syst Appl Microbiol ; 24(4): 549-53, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11876362

RESUMO

Because of differences in the reported 16S rRNA gene sequence of the Mesorhizobium loti type strain available from different culture collections, we collected different subcultures of this strain and compared them by 16S rDNA sequencing, SDS-PAGE of whole-cell protein extracts and RAPD-PCR. Our results indicate that the 16S rDNA sequence differences can be explained by the presence of two different organisms in one of the subcultures. In addition, even for subcultures of the type strain that had identical 16S rDNA sequences, small differences could be observed in the protein profiles and in the RAPD-PCR patterns. These latter observations indicate that maintenance procedures necessary for long-term preservation by freeze-drying can cause subcultures of the same original strain to undergo changes, effectively leading to different fingerprints even though 16S rDNA sequences remain identical.


Assuntos
DNA Bacteriano/genética , RNA Ribossômico 16S/genética , Rhizobium/genética , Impressões Digitais de DNA , DNA Bacteriano/química , Eletroforese em Gel de Poliacrilamida , Filogenia , RNA Ribossômico 16S/química , Técnica de Amplificação ao Acaso de DNA Polimórfico , Rhizobium/química , Rhizobium/classificação , Ribotipagem , Análise de Sequência de DNA
14.
Cytometry ; 41(2): 96-101, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11002264

RESUMO

BACKGROUND: Electroporation accomplishes transient permeabilization of cells and thus aids in the uptake of drugs. The method has been employed clinically in the treatment of dermatological tumors with bleomycin. The conditions of electroporation are still largely empirical and information is lacking as to the interrelationships among voltage pulse height, pulse number and toxicity, cell permeation, drug uptake, and effects on drug toxicity. We used propidium iodide (PI) and flow cytometry to define cell permeation into cytoplasmic and nuclear compartments to determine the improvements of drug toxicity that can be accomplished by electroporation. METHODS: Human squamous carcinoma cells of defined TP53 status and normal human epithelial cells were subjected to electroporation using a square wave pulse generator in the range of 0-5,000 V/cm. Flow cytometry served to establish entry of the drug reporter, PI, into the cytoplasm and nucleus. A dye staining method served to establish cell survival and to determine the toxicity of bleomycin alone, electroporation alone, and electroporation with bleomycin. RESULTS: The electric field intensity (EFI) required to produce 50% permeabilization (EP(50)) is cell type dependent. The EP(50) varied from 1,465 to 2,027 V/cm. An EFI below 900 V/cm is growth stimulatory whereas an EFI in excess of 1,000 V/cm is growth inhibitory. An EFI of 1,000 V/cm is sufficient to increase bleomycin toxicity by a factor of 2-3. A differential electroporation efficiency is observed between normal and tumor cells. CONCLUSIONS: Tumor cells can be targeted preferentially at electroporation voltages where normal cells are less permeable.


Assuntos
Permeabilidade da Membrana Celular , Eletroporação/métodos , Citometria de Fluxo , Propídio/farmacologia , Antibióticos Antineoplásicos/farmacologia , Bleomicina/farmacologia , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , DNA/metabolismo , Eletroquímica , Humanos , Indicadores e Reagentes/metabolismo , Indicadores e Reagentes/farmacologia , Substâncias Intercalantes/metabolismo , Substâncias Intercalantes/farmacologia , Membrana Nuclear/metabolismo , Permeabilidade , Propídio/metabolismo , Células Tumorais Cultivadas
15.
Br J Pharmacol ; 130(7): 1513-24, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10928952

RESUMO

Several drugs used in the treatment of chronic peripheral ischaemic and venous diseases, i.e. aescine, Cyclo 3, Ginkor Fort, hydroxyethylrutosides, naftidrofuryl, naphthoquinone and procyanidolic oligomers, were tested on the mitochondrial respiratory activity. The results show that all these drugs protected human endothelial cells against the hypoxia-induced decrease in ATP content. In addition, they all induced a concentration-dependent increase in respiratory control ratio (RCR) of liver mitochondria pre-incubated with the drugs for 60 min. The drugs were divided into two groups according to their effects. The first group (A), comprising aescine, Ginkor Fort, naftidrofuryl and naphthoquinone, increased RCR by decreasing state 4 respiration rate. The second group of drugs (B), comprising hydroxyethylrutosides, procyanidolic oligomers and Cyclo 3, increased RCR by increasing state 3 respiration rate. The drugs of group A were able to prevent the inhibition of complexes I and III respectively by amytal and antimycin A while the first two drugs of group B increased adenine nucleotide translocase activity. Cyclo 3 inhibited the carbonylcyanide m-chlorophenyl hydrazone (mCCP)-induced uncoupling of mitochondrial respiration. None of these seven drugs could protect complexes IV and V, respectively, from inhibition by cyanide and oligomycin. When tested on endothelial cells the drugs of group A, in contrast to group B, prevented the decrease in ATP content induced by amytal or antimycin A. The present results suggest that the protective effects on mitochondrial respiration activity by these venotropic drugs may explain their protective effect on the cellular ATP content in ischaemic conditions and some of their beneficial therapeutic effect in chronic vascular diseases.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Extratos Vegetais/farmacologia , Vasodilatadores/farmacologia , Trifosfato de Adenosina/metabolismo , Amobarbital/farmacologia , Análise de Variância , Animais , Antibacterianos/farmacologia , Antimicina A/farmacologia , Hipóxia Celular/efeitos dos fármacos , Respiração Celular/efeitos dos fármacos , Células Cultivadas , Endotélio Vascular/fisiologia , Feminino , Flavonoides/farmacologia , Moduladores GABAérgicos/farmacologia , Ginkgo biloba , Humanos , Técnicas In Vitro , Mitocôndrias/fisiologia , Ratos , Ratos Wistar , Veias Umbilicais/citologia
16.
Fundam Clin Pharmacol ; 14(3): 193-201, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-15602795

RESUMO

Ischaemia is a common feature of most vascular diseases. There is evidence from experimental and clinical studies that Ginkgo biloba extract protects tissues from ischaemia/reperfusion damages. Bilobalide seems to be responsible, at least in part, for this activity. However, the mechanism of the protection afforded by bilobalide is not yet known. In this work, the effects of bilobalide on mitochondrial respiration were investigated during liver and brain ischaemia, since mitochondria alteration is an early event in ischaemia-induced damage. Bilobalide could prevent the decrease in respiratory activity induced by ischaemia in liver and in brain, both when glutamate/malate or succinate was used as substrate. Ischaemia decreased state 3 respiration rate and bilobalide prevented this decrease. While bilobalide was not able to prevent the decrease in adenine translocase activity, it protected complex I activity. Bilobalide allows mitochondria to maintain their respiratory activity in ischaemic conditions by protecting complex I and probably complex III activities. Hence, the energetic pool of tissues is preserved during the ischaemic period as well as its viability. This mechanism provides, a possible explanation for the anti-ischaemic properties of bilobalide and of Ginkgo biloba extract in therapeutic interventions.


Assuntos
Ciclopentanos/uso terapêutico , Diterpenos/uso terapêutico , Furanos/uso terapêutico , Isquemia/prevenção & controle , Fígado/metabolismo , Mitocôndrias/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Animais , Isquemia Encefálica/enzimologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/prevenção & controle , Ciclopentanos/administração & dosagem , Ciclopentanos/farmacologia , Modelos Animais de Doenças , Diterpenos/administração & dosagem , Diterpenos/farmacologia , Relação Dose-Resposta a Droga , Feminino , Furanos/administração & dosagem , Furanos/farmacologia , Ginkgolídeos , Isquemia/enzimologia , Isquemia/metabolismo , Fígado/irrigação sanguínea , Fígado/enzimologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/enzimologia , Mitocôndrias Hepáticas/metabolismo , Translocases Mitocondriais de ADP e ATP/metabolismo , NADH Desidrogenase/metabolismo , Ratos , Ratos Wistar
17.
Biochem Pharmacol ; 58(1): 109-19, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10403524

RESUMO

Mitochondria alteration is an early event in ischemia-induced damage, and its prevention improves tissue survival upon reperfusion. Adenine translocase and complex I activities are rapidly affected by ischemia. Ginkgo biloba extract demonstrates anti-ischemic properties attributable to the terpenoid fraction, mainly due to the presence of bilobalide. The mechanism of the protection afforded by bilobalide is not yet known. In this work, the effects of bilobalide on mitochondrial respiration were investigated. Mitochondria isolated from rats treated with bilobalide (2 to 8 mg/kg) showed a dose-dependent increase in the respiratory control ratio, due to a lower oxygen consumption during state 4. Bilobalide also decreased the sensitivity of oxygen consumption to inhibition of complex I by Amytal or to inhibition of complex III by antimycin A or myxothiazol. There was no protection of complexes IV and V. It also increased the activity of complex I but not of adenine translocase. Similar effects were also obtained in vitro when control mitochondria were preincubated for 1 hr with 0.8 microg/mL bilobalide. Treatment of the rats with 8 mg/kg bilobalide also prevented the ischemia-induced decrease in state 3 of the mitochondrial respiration and thus the decrease in RCR. The protective effect of bilobalide on cellular ATP content observed under ischemic conditions can be correlated with the above observations. By protecting complex I and III activities, bilobalide allows mitochondria to maintain their respiratory activity under ischemic conditions as long as some oxygen is present, thus delaying the onset of ischemia-induced damage. This mechanism provides a possible explanation for the anti-ischemic properties of bilobalide and of Ginkgo biloba extract in therapeutic interventions.


Assuntos
Ciclopentanos/farmacologia , Diterpenos , Furanos/farmacologia , Mitocôndrias Hepáticas/efeitos dos fármacos , Animais , Respiração Celular/efeitos dos fármacos , Ciclopentanos/antagonistas & inibidores , Ciclopentanos/uso terapêutico , Feminino , Furanos/antagonistas & inibidores , Furanos/uso terapêutico , Ginkgolídeos , Técnicas In Vitro , Isquemia/metabolismo , Fígado/irrigação sanguínea , Fígado/efeitos dos fármacos , Fígado/metabolismo , Mitocôndrias Hepáticas/fisiologia , NAD(P)H Desidrogenase (Quinona)/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Perfusão , Substâncias Protetoras/farmacologia , Ratos , Ratos Wistar
19.
Int J Syst Bacteriol ; 49 Pt 2: 663-9, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10319489

RESUMO

An integrated genotypic and phenotypic analysis of 12 Centers for Disease Control (CDC) group IVc-2 strains revealed that this taxon represents a novel species belonging to the genus Ralstonia. Comparative 16S rDNA sequence analysis allocated a representative CDC group IVc-2 strain to the Ralstonia branch of the beta subclass of the Proteobacteria. DNA-DNA hybridizations did not detect significant binding levels towards any presently known Ralstonia species, including Ralstonia pickettii. Its DNA base ratio is between 65 and 67 mol%. The name Ralstonia paucula sp. nov. is proposed, with strain LMG 3244 (= CDC E6793), isolated from a human respiratory tract, as the type strain. R. paucula can be differentiated from other Ralstonia species by whole-cell protein analysis, amplified rDNA restriction analysis and a variety of classical biochemical tests. Strains have been isolated from various human clinical and environmental sources.


Assuntos
Bactérias Gram-Negativas/classificação , Infecções por Bactérias Gram-Negativas/microbiologia , Proteínas de Bactérias/química , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Eletroforese em Gel de Poliacrilamida , Microbiologia Ambiental , Genes de RNAr , Bactérias Gram-Negativas/genética , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Negativas/fisiologia , Humanos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
20.
J Cardiovasc Pharmacol ; 33(1): 7-11, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9890390

RESUMO

One possible mechanism that accounts for the alterations observed in varicose veins is the activation of endothelial cells by ischemia occurring in the leg veins during blood stasis and the cascade of reactions that follows. Because in vitro data suggest that endothelium alteration is a key event in the development of the pathology, it was important to confirm this hypothesis in patients. We used the number of circulating endothelial cells detached from the vascular wall as a criterion of the endothelium injury. We first compared the number of circulating endothelial cells (CECs) in patients with chronic venous insufficiency (CVI) with those of a control population. A twofold increase in the CEC count (1,001+/-127 CEC/ml of plasma compared with 514+/-82 CECs/ml) was observed in CVI patients, which indeed suggests an alteration of the endothelium in this disease. Second, the protective effect of a venotropic drug, Ginkgo biloba extract, troxerutine, and heptaminol (Ginkor Fort), was tested by a randomized double-blind, placebo-controlled clinical trial. In the active-treatment group, the mean values of the CEC count decreased by 14.5% after a 4-week treatment, whereas in the placebo group, the decrease was less (8.4%). The decrease from week 0 to the end of treatment was significantly higher in the active-treatment group than in the placebo group. These results confirm the important role of the endothelium alterations in the development of varicose veins and suggest a potential beneficial action of a venotropic drug on the venous wall.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Flavonoides/uso terapêutico , Extratos Vegetais , Insuficiência Venosa/tratamento farmacológico , Adulto , Idoso , Contagem de Células/efeitos dos fármacos , Doença Crônica , Método Duplo-Cego , Endotélio Vascular/patologia , Endotélio Vascular/fisiologia , Feminino , Flavonoides/farmacologia , Ginkgo biloba , Humanos , Pessoa de Meia-Idade , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Insuficiência Venosa/patologia
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