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1.
Br J Dermatol ; 185(5): 988-998, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33959940

RESUMO

BACKGROUND: Genome-wide association studies (GWASs) have identified genes influencing skin ageing and mole count in Europeans, but little is known about the relevance of these (or other genes) in non-Europeans. OBJECTIVES: To conduct a GWAS for facial skin ageing and mole count in adults < 40 years old, of mixed European, Native American and African ancestry, recruited in Latin America. METHODS: Skin ageing and mole count scores were obtained from facial photographs of over 6000 individuals. After quality control checks, three wrinkling traits and mole count were retained for genetic analyses. DNA samples were genotyped with Illumina's HumanOmniExpress chip. Association testing was performed on around 8 703 729 single-nucleotide polymorphisms (SNPs) across the autosomal genome. RESULTS: Genome-wide significant association was observed at four genome regions: two were associated with wrinkling (in 1p13·3 and 21q21·2), one with mole count (in 1q32·3) and one with both wrinkling and mole count (in 5p13·2). Associated SNPs in 5p13·2 and in 1p13·3 are intronic within SLC45A2 and VAV3, respectively, while SNPs in 1q32·3 are near the SLC30A1 gene, and those in 21q21·2 occur in a gene desert. Analyses of SNPs in IRF4 and MC1R are consistent with a role of these genes in skin ageing. CONCLUSIONS: We replicate the association of wrinkling with variants in SLC45A2, IRF4 and MC1R reported in Europeans. We identify VAV3 and SLC30A1 as two novel candidate genes impacting on wrinkling and mole count, respectively. We provide the first evidence that SLC45A2 influences mole count, in addition to variants in this gene affecting melanoma risk in Europeans.


Assuntos
Melanoma , Envelhecimento da Pele , Adulto , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , Envelhecimento da Pele/genética
2.
Solid State Nucl Magn Reson ; 104: 101623, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31678745

RESUMO

We carried out a detailed investigation of the local ordering and dynamics of the lithium intercalation in paramagnetic LixVOPO4.2H2O (with 0 < x ≤ 1) materials. This question was addressed using a combination of X-ray diffraction, 31P and 7Li MAS NMR experiments. We first studied the structure of the fully ordered end-member of the series, Li1VOPO4.2H2O, revisiting the X-ray single crystal diffraction data on the basis of the information provided by 31P MAS NMR. We then carried out 7Li MAS and exchange NMR experiments and 31P MAS experiments on the polycrystalline powders obtained after partial lithium insertion in VOPO4.2H2O phases. These experiments evidenced an unexpected ageing of the material related with lithium dynamics between the VOPO4 layers and a V4+/V5+ charge ordering mechanism within the layers.

3.
Mol Genet Genomics ; 292(6): 1209-1219, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28688048

RESUMO

The genetic risk of developing type 2 diabetes (T2D) increases in parallel with the proportion of Native American ancestry. Mestizo Mexicans have a 70% Native Amerindian genetic background. The T130I polymorphism in the HNF4A gene has been associated with early-onset T2D in mestizo Mexicans. Thus, the aim of the present study was to evaluate the frequency and relationship of the T130I variant in the HNF4A gene with risk factors for developing T2D in eleven indigenous groups from Mexico. In two groups, all exons of the HNF4A gene were directly sequenced; in the remaining the T130I polymorphism was analyzed by restriction fragment length polymorphism. Ancestry informative markers were assessed to confirm the Amerindian component. An additional analysis of EHH was carried out. Interestingly, HNF4A gene screening revealed only the presence of the T130I polymorphism. The range frequency of the risk allele (T) in the indigenous groups was from 2.7 to 16%. Genotypic frequencies (T130I/I130I) were higher and significantly different from those of all of the populations included in the HapMap Project (P < 0.005). EHH scores suggest a positive selection for T130I polymorphism. Metabolic traits indicate a relationship between the T130I/I130I genotypes with high triglyceride concentrations in the indigenous groups (P < 0.005). These results strongly suggest that the high frequency of the T130I polymorphism and its biological relationship with dysfunction in lipid metabolism in Mexican indigenous groups is a risk factor for the developing of T2D in Mexicans.


Assuntos
Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Fator 4 Nuclear de Hepatócito/genética , Estudos Transversais , Diabetes Mellitus Tipo 2/etnologia , Etnicidade/genética , Haplótipos , Humanos , México/etnologia , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único
4.
Pharmacogenomics J ; 16(6): 559-565, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26503810

RESUMO

N-acetyltransferase 2 (NAT2) is responsible for metabolizing xenobiotics; NAT2 polymorphisms lead to three phenotypes: rapid, intermediate and slow acetylators. We aimed to investigate NAT2 diversity in Native Americans. NAT2 exon 2 was sequenced for 286 individuals from 21 populations (Native American and American Mestizos). Excluding the basal/rapid haplotype NAT2*4, the most frequent haplotypes are NAT2*5B (35.95%) in hunter-gatherers and NAT2*7B (20.61%) and NAT2*5B (19.08%) in agriculturalists that were related to the slow phenotype. A new haplotype was identified in two Amerindians. Data from the ~44 kb region surrounding NAT2 in 819 individuals from Africa, East-Asia, Europe and America were used in additional analyses. No significant differences in the acetylator NAT2 haplotype and phenotype distributions were found between Native American populations practicing farming and/or herding and those practicing hunting and gathering, probably because of the absence or weakness of selection pressures and presence of demographic and random processes preventing detection of any selection signal.


Assuntos
Indígena Americano ou Nativo do Alasca/genética , Arilamina N-Acetiltransferase/genética , Evolução Molecular , Variação Genética , Acetilação , Agricultura , América , Animais , Arilamina N-Acetiltransferase/metabolismo , Dieta/etnologia , Comportamento Alimentar/etnologia , Frequência do Gene , Haplótipos , Humanos , Cinética , Fenótipo , Comportamento Predatório , Xenobióticos/metabolismo
5.
Rev. chil. nutr ; 36(2): 143-150, jun. 2009. tab
Artigo em Espanhol | LILACS | ID: lil-554841

RESUMO

Se midieron las cantidades de acido linoleico conjugado (ALC) - isómeros: cis-9, trans-11, trans-10, cis-12 y cis-10, cis-12 -en leche de estanque de la empresa NESTLE y de alimentos lácteos en Chile, mediante cromatografía de gas. El ALC encontrado fue más alto (p < 0.05) en las muestras tomadas en la ciudad de Osorno comparado con la leche de la ciudad de Los Angeles. A nivel estacional el valor más alto de ALC de leche líquida fue encontrado durante la primavera en la ciudad Osorno (1,72 g/100g), mientras que el valor más bajo se presentó en invierno (0,415 g/100g) en la ciudad de Los Angeles. La cantidad promedio de ALC en leche en polvo y de leche condensada fue de 1,967 y 1,493 g/100g respectivamente durante el año 2004. La mantequilla, el queso y la crema presentaron promedios de 1,502,0,883 y 1,900 g/ lOOg respectivamente de ALC. Se concluye que los productos lácteos analizados tienen altos valores de ALC en Chile.


The amounts of conjugated linoleic acid (ALC) - homers: cis-9, trans-11, trans-10, cis-12 and cis-10, cis-12- were measured in a milk tank of the NESTLE Company and of diary food in Chile and were analyzed through gas chromatography. The ALC was found higher (p <0.05) in samples taken in the city of Osorno compared to milk of the city of Los Angeles. The highest value was found during spring in Osorno (1,72 g/100 g), while the lowest value (0,415 g/100 g) was found in winter in Los Angeles. The average amount of ALC in milk powder and condensed milk was of 1,967 and 1,493 g/100 g, respectively, during 2004. Butter, cheese and cream had respectively an average of 1,502, 0,883 and 1,900 g/100 g. In conclusion, the diary products analyzed have a high value of ALC in Chile.


Assuntos
Ácidos Linoleicos Conjugados/análise , Cromatografia Gasosa , Laticínios/análise , Chile , Leite/química
6.
J Appl Microbiol ; 102(6): 1544-50, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17578419

RESUMO

AIMS: The in vitro activity of some essential oils (EO) (thyme red, fennel, clove, pine, sage, lemon balm and lavender) against clinical and environmental fungal strains was determined. METHODS AND RESULTS: The minimal inhibitory concentrations were determined by a microdilution method in RPMI 1640 and by a vapour contact assay. The composition of oils was analysed by gas chromatography (GC) and GC/mass spectrometry. The results indicated that the oils antifungal activity depended on the experimental assay used. The inhibiting effects of EO in vapour phase were generally higher than those in liquid state. According to both methods thyme red and clove were found to be the oils with the widest spectrum of activity against all fungi tested. CONCLUSIONS: Despite the differences between the two methods, our results demonstrate that some EO are very active on dermatophytes and dematiaceous fungi. However, more data will be necessary to confirm this good in vitro efficacy. SIGNIFICANCE AND IMPACT OF THE STUDY: This study could identify candidates of EO for developing alternative methods to control environmental and clinically undesirable filamentous fungi.


Assuntos
Antifúngicos/farmacologia , Fungos Mitospóricos/efeitos dos fármacos , Óleos Voláteis/farmacologia , Alternaria/efeitos dos fármacos , Antifúngicos/química , Aspergillus/efeitos dos fármacos , Cladosporium/efeitos dos fármacos , Ionização de Chama/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Testes de Sensibilidade Microbiana , Mucor/efeitos dos fármacos , Óleos Voláteis/química , Penicillium/efeitos dos fármacos , Rhizopus/efeitos dos fármacos
7.
Clin Exp Immunol ; 148(3): 469-77, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17493019

RESUMO

Tuberculosis remains one of the most important infectious diseases worldwide. Several studies have suggested that genetic factors may affect susceptibility to tuberculosis, but the specific genes involved have not yet been fully characterized. NRAMP1/SLC11 A1 and P2X(7) genes have been linked to increased risk for tuberculosis in some African and Asiatic populations. To explore the potential role of these genes in the susceptibility to pulmonary tuberculosis in a Mexican mestizo population, we evaluated the association of D543N and 3'-UTR polymorphisms in NRAMP1/SLC11 A1 and - 762 and A1513C polymorphisms in P2X(7) genes with the risk for tuberculosis. Polymerase chain reaction (PCR) amplification of genomic DNA followed by restriction fragment length polymorphism analysis, and allelic-specific PCR was employed. We found no significant differences in allelic frequency in NRAMP1/SLC11 A1 gene polymorphisms in 94 patients with tuberculosis compared to 100 healthy contacts. Similarly, no significant association of the P2X(7)-762 gene polymorphism with tuberculosis was detected. In contrast, the P2X(7) A1513C polymorphism was associated significantly with tuberculosis (P = 0.02, odds ratio = 5.28, 95% CI, 0.99-37.69), an association that had not been reported previously. However, when the function of P2X(7) was assessed by an L-selectin loss assay, we did not find significant differences in patients compared to healthy contacts or between PPD(+) and PPD(-) control individuals. This study further supports the complex role of P2X(7) gene in host regulation of Mycobacterium tuberculosis infection, and demonstrates that different associations of gene polymorphisms and tuberculosis are found in distinct racial populations.


Assuntos
Proteínas de Transporte de Cátions/genética , Polimorfismo de Fragmento de Restrição , Receptores Purinérgicos P2/genética , Tuberculose Pulmonar/genética , Estudos de Casos e Controles , Proteínas de Transporte de Cátions/sangue , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Selectina L/sangue , Leucócitos Mononucleares/metabolismo , Masculino , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/genética , Receptores Purinérgicos P2/sangue , Receptores Purinérgicos P2/fisiologia , Receptores Purinérgicos P2X7 , Tuberculose Pulmonar/sangue
8.
Phytother Res ; 20(3): 187-90, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16521108

RESUMO

Propolis and Zingiber officinale have been shown to be specifically targeted against Helicobacter pylori strains, to possess antiinflammatory, antioxidant and antitumoral activity and to be used in traditional medicine for the treatment of gastrointestinal ailments. Considering that these natural products could potentially serve as novel therapeutic tools also in combination with an antibiotic, the aim of this work was to evaluate their effect when combined with clarithromycin on clinical H. pylori isolates (n = 25), characterized in respect to both clarithromycin susceptibility and the presence of the cagA gene. The results showed that the combinations of propolis extract + clarithromycin and Z. officinale extract + clarithromycin exhibited improved inhibition of H. pylori with synergistic or additive activity. Interestingly, the susceptibility to combinations was significantly independent of the microbial clarithromycin susceptibility status. Only one H. pylori strain showed antagonism towards the Z. officinale extract + clarithromycin combination. The data demonstrate that combinations of propolis extract + clarithromycin and Z. officinale extract + clarithromycin have the potential to help control H. pylori-associated gastroduodenal disease.


Assuntos
Antibacterianos/farmacologia , Claritromicina/farmacologia , Helicobacter pylori/efeitos dos fármacos , Extratos Vegetais/farmacologia , Própole/farmacologia , Zingiber officinale/química , Adulto , Análise de Variância , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Combinação de Medicamentos , Sinergismo Farmacológico , Etanol/química , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/classificação , Helicobacter pylori/genética , Humanos , Masculino , Medicina Tradicional , Testes de Sensibilidade Microbiana , Própole/química
9.
Forensic Sci Int ; 164(2-3): 266-70, 2006 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-16426785

RESUMO

Allelic frequencies of 15 short tandem repeats (STR) markers (CSF1PO, FGA, THO1, TPOX, VWA, D3S11358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, D19S433 and D2S1338) were determined using the AmpFl STR Identifiler PCR Amplification Kit in Puerto Rican American individuals (N=205) from Massachusetts. The FGA, D18S51 and D2S1338 loci had a high power of discrimination (PD) with values of 0.967, 0.965 and 0.961, respectively. Significant deviations from the Hardy-Weinberg (HW) equilibrium were not detected. An important genetic contribution of Caucasian European (76.4%) was detected in Puerto Rican Americans. However, comparative analysis between Puerto Rican American and other neighboring populations from United States mainly with African and Caucasian Americans, revealed significant differences in the distribution of STR markers. Our results are important for future comparative genetic studies of different American ethnic groups, in particular a cultural group called Hispanic-Americans and should be helpful for forensic and paternity testing.


Assuntos
Frequência do Gene , Genética Populacional , Hispânico ou Latino/genética , Sequências de Repetição em Tandem , Impressões Digitais de DNA , Humanos , Massachusetts , Reação em Cadeia da Polimerase , Porto Rico/etnologia
10.
Phytother Res ; 19(3): 198-202, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15934015

RESUMO

The aim of this work was to evaluate the antibacterial effect of plant extracts as alternative and[sol ]or as active agents supporting antibiotics for treating Helicobacter pylori infection. The effect of either, ethanolic or aqueous extracts from 17 plant materials were studied against one H. pylori standard strain and 11 clinical isolates using a disc diffusion test and by evaluating the minimum inhibitory concentration (MIC) on solid media. An inhibitory activity against H. pylori strains was recorded in a large percentage of tested plants. MIC values of ethanolic extracts were from two to four concentration steps lower than the aqueous ones. In particular, ethanolic extracts of Cuminum cyminum L. and Propolis expressed MIC90 values of 0.075 mg/mL. The results show a significant in vitro effect of plant extracts against H. pylori that could be considered a valuable support in the treatment of the infection and may contribute to the development of new and safe agents for inclusion in anti-H. pylori regimens.


Assuntos
Antibacterianos/farmacologia , Cuminum , Helicobacter pylori/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/farmacologia , Própole , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico
11.
J Appl Microbiol ; 97(2): 395-401, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15239707

RESUMO

AIMS: To verify the efficiency of Calamintha officinalis essential oil as natural preservative in two current formulations. METHODS AND RESULTS: The 1.0 and 2.0% (v/v) C. officinalis essential oil was assayed for its preservative activity in two product types (cream and shampoo). The microbial challenge test was performed following the standards proposed by the European Pharmacopoeia Commission (E.P.) concerning topical preparations using standard micro-organisms and in addition wild strains, either in single or mixed cultures were used. The results clearly demonstrated that the C. officinalis essential oil at 2.0% concentration reduced the microbial inoculum satisfying the criterion A of the E.P. in the cream formulation and the criterion B in the shampoo formulation. Standard and wild strains showed a behaviour similar, both in cream and in shampoo formulation, with no significant difference (gerarchic variance, P > 0.05). CONCLUSION: C. officinalis essential oil confirmed its preservative properties but at higher concentration than that shown in previous studies on cetomacrogol cream. SIGNIFICANCE AND IMPACT OF THE STUDY: The nature of the formulation in which an essential oil is incorporated as preservative could have considerable effect on its efficacy.


Assuntos
Lamiaceae , Óleos Voláteis , Óleos de Plantas , Conservantes Farmacêuticos , Anti-Infecciosos , Cosméticos , Contaminação de Medicamentos/prevenção & controle , Testes de Sensibilidade Microbiana/métodos , Pomadas , Plantas Medicinais
12.
Lett Appl Microbiol ; 38(5): 423-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15059215

RESUMO

AIMS: The purpose of the present study was to examine whether sublethal concentrations of Helichrysum italicum extract could affect some of the cariogenic properties of Streptococcus mutans. METHODS AND RESULTS: We studied the antibacterial activity of H. italicum (ethanolic extract) against oral streptococci (Strep. mutans ATCC 35668, Strep. salivarius ATCC 13419 and Strep. sanguis ATCC 10556) and its influence on cell-surface hydrophobicity, in vitro sucrose-dependent adherence to glass surface and cellular aggregation of Strep. mutans. The results indicate that all streptococci were susceptible to ethanolic extract with minimum inhibitory concentration (MIC) values of 31.25-62.50 microg x ml(-1). Sub-MIC concentrations of H. italicum (7.81-31.25 microg x ml(-1)) reduced the hydrophobicity and the adherence (almost 90%) to glass surface of Strep. mutans. The aggregation in the presence of dextran T2000 was also affected. CONCLUSION: The inhibitory activity of H. italicum extract on Strep. mutans is worthy of further study. SIGNIFICANCE AND IMPACT OF THE STUDY: There is considerable interest in the use of natural compounds as alternative methods to control undesirable micro-organisms.


Assuntos
Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Helichrysum/química , Interações Hidrofóbicas e Hidrofílicas , Extratos Vegetais/farmacologia , Streptococcus mutans/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus mutans/fisiologia
13.
Lett Appl Microbiol ; 35(5): 385-9, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12390486

RESUMO

AIMS: This study was focused on the preserving properties of Calamintha officinalis essential oil, a plant known for its diaphoretic, expectorant and aromatic properties. METHODS AND RESULTS: The commercial aerial parts of C. officinalis Moench were hydrodistilled and the essential oil analysed by Gas chromatography/Electron impact mass spectrometry (GC/EIMS). The inhibition efficacy of this essence, alone (0.5 and 1.0% v/v) and in combination with 2.0 mM EDTA, was assayed, in culture medium and in cetomacrogol cream, using preservative efficacy testing against standard microrganisms (E. coli ATCC 25922, Ps. aeruginosa ATCC 9027, Staph. aureus ATCC 6538P, C. albicans ATCC 10231 and A. niger ATCC 16404). C. officinalis essential oil in cetomacrogol cream with EDTA showed long-lasting antimicrobial activity, satisfying the European Pharmacopoeia Commission (E. P.) criteria. CONCLUSION: C. officinalis essential oil could have a potential for a future use as a cosmetic preservative. IMPACT OF THE STUDY: To find natural compounds with antimicrobial activity which could be alternatives to the synthetic chemical preservatives.


Assuntos
Ácido Edético/farmacologia , Microbiologia Industrial , Óleos Voláteis/farmacologia , Plantas Medicinais/metabolismo , Conservantes Farmacêuticos/farmacologia , Aspergillus niger/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Cetomacrogol/metabolismo , Meios de Cultura , Escherichia coli/efeitos dos fármacos , Óleos de Plantas/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
14.
Lett Appl Microbiol ; 35(3): 181-4, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12180937

RESUMO

AIMS: The purpose of this work was to evaluate the effect of Helichrysum italicum extract on enterotoxin (A-D) production by Staphylococcus aureus strains. METHODS AND RESULTS: The production of enterotoxins A-D in the presence or absence of H.italicum diethyl ether extract was estimated in microtiter plates using a reversed passive latex agglutination (SET-RPLA) kit (Oxoid, Basingstoke, UK). The results indicate that, in culture medium, inhibition of staphylococcal growth and enterotoxins appeared with 250-125 microg ml(-1) of the extract. Lower concentrations of the extract (62.5-31.25 microg ml(-1)) did not affect the final viable count of Staph. aureus but reduced the production of enterotoxins B and C. CONCLUSIONS: H. italicum interferes with growth and production of enterotoxins by Staph. aureus. SIGNIFICANCE AND IMPACT OF THE STUDY: There is considerable interest in the use of natural compounds as alternative methods to control undesirable pathogenic micro-organisms.


Assuntos
Asteraceae , Enterotoxinas/biossíntese , Extratos Vegetais/farmacologia , Staphylococcus aureus/metabolismo , Contagem de Colônia Microbiana , Testes de Fixação do Látex , Testes de Sensibilidade Microbiana , Kit de Reagentes para Diagnóstico , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
15.
Int J Antimicrob Agents ; 18(6): 583-5, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11738350

RESUMO

Nepeta cataria L., commonly known as catnip, is a perennial herb with a considerable folkloric reputation. A diethyl ether extract of this plant has been shown to have antimicrobial activity against fungi and Gram-positive bacteria. The aim of this work was to study the activity of N. cataria extract on 44 Staphylococcus aureus strains, some resistant to methicillin, and S. aureus 6538P (American Type Culture Collection) by evaluating the effect of subminimum inhibitory concentrations on coagulase, DNAse, thermonuclease and lipase production, and on in-vitro adherence. DNAse, thermonuclease and lipase were inhibited by concentrations equal to 1/2 and 1/4 MIC. A reduction of adherence was also observed.


Assuntos
Nepeta , Staphylococcus aureus/efeitos dos fármacos , Aderência Bacteriana/efeitos dos fármacos , Coagulase/biossíntese , Desoxirribonucleases/biossíntese , Éter , Humanos , Lipase/biossíntese , Testes de Sensibilidade Microbiana , Nuclease do Micrococo/biossíntese , Extratos Vegetais/farmacologia , Staphylococcus aureus/metabolismo
16.
Mar Environ Res ; 52(4): 301-21, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11695652

RESUMO

Field studies were carried out to determine and compare the impact of organic loads due to the biodeposition of a mussel farm on the water quality and sediment in a coastal area of the Tyrrhenian Sea (Western Mediterranean). A total of five environmental and five microbial parameters were examined from March, 1997 to February, 1998 on a monthly basis at three stations: the first was located under the mussel farm, the second located at about 40 m away from the mussel farm, while the third designed as a control was at about 1-km. No clear changes in the physical characteristics of the water masses were observed, comparing the three sampling sites and the water column generally showed homogeneous conditions (in terms of temperature and salinity). Changes in density of aerobic heterotrophic bacteria, Escherichia coli and Enterococci in the water column are apparently independent from changes in environmental parameters. At all stations a constant significant correlation between temperature and presumptive Vibrio parahaemolyticus was reported suggesting that this abiotic factor exerted a major control on this bacterial group and its distribution in the water column is not related to the biodeposition of the mussel farm. The major impact identified was on the sediment where variations in bacterial abundance was observed. In the Mussel station sediment enrichment of organic compounds, and the consequent modification of the characteristics of the benthic environment, determined an increase in aerobic heterotrophic bacteria, and particularly of vibrios density (on average about 60%), suggesting that these bacteria are good indicators of organic enrichment.


Assuntos
Aquicultura , Bactérias , Bivalves , Microbiologia da Água , Poluentes da Água/análise , Animais , Monitoramento Ambiental/métodos , Sedimentos Geológicos , Compostos Orgânicos , Dinâmica Populacional
17.
Int J Antimicrob Agents ; 17(6): 517-20, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11397624

RESUMO

Helichrysum italicum G. Don (Compositae) is a shrub commonly found in dry, sandy and stony areas of Mediterranean regions. This plant is known for its anti-inflammatory, anti-allergic and antimicrobial activity. The aim of this study was to evaluate the effect of the diethyl ether extract on growth of Staphylococcus aureus (ATCC 6538P, MRSA and MSSA isolates) and the influence of subminimum inhibitory concentrations (subMICs) on some enzymes which are considered virulence factors. The results indicate that the H. italicum extract had an inhibitory effect on S. aureus strains reducing both their growth and some of the enzymes such as coagulase, DNAse, thermonuclease and lipase. Helichrysum italicum extract could be a novel antimicrobial agent, less toxic to human skin and tissues, worthy of further studies.


Assuntos
Asteraceae , Plantas Medicinais , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Coagulase/antagonistas & inibidores , Desoxirribonucleases/antagonistas & inibidores , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Humanos , Técnicas In Vitro , Lipase/antagonistas & inibidores , Nuclease do Micrococo/antagonistas & inibidores , Extratos Vegetais/farmacologia , Staphylococcus aureus/enzimologia , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/isolamento & purificação
18.
New Microbiol ; 22(2): 91-8, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10322607

RESUMO

Wild, pigmented strains of Serratia marcescens and their non-pigmented mutants were compared on the basis of fatty acid profiles and lipid content. Classic biochemical tests show only minor differences, as well as fatty acid ratio C18:C16. The total amount of lipid synthesized and the saturated/unsaturated fatty acids ratio disclose a sharp total lipid reduction and a high percentage of unsaturated fatty acids in the pigmented strains, placing them in separated clusters compared with the nonpigmented mutants. It is hypothesized that the synthesis of the polyacetate required for the completion of the prodigiosin molecule may result in waste of methyl groups and thus affect the total amount of lipids.


Assuntos
Ácidos Graxos/análise , Pigmentos Biológicos/biossíntese , Prodigiosina/biossíntese , Serratia marcescens/metabolismo , Cromatografia Gasosa , Serratia marcescens/química , Espectroscopia de Infravermelho com Transformada de Fourier
19.
New Microbiol ; 22(2): 129-38, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10322612

RESUMO

Vibrio cholerae non O1 is known to persist in estuarine and freshwater environments. Experiments evaluated the amount of microorganisms accumulated in mussels maintained in static seawater, contaminated with 10(4) to 10(6) cells/ml and the depuration time required in circulating water. Accumulation and retention times were compared with those for Escherichia coli, Salmonella typhi and Vibrio harvey. E. coli and S. typhi accumulated to a greater extent and were released from mussels more quickly than vibrios which became undetectable 2 to 3 days later than E. coli. Seasonal seawater temperatures (14 to 21 degrees C) had a limited influence on depuration but vibrios appear to be retained with more efficacy over 16 degrees C while E. coli and S. typhi were eliminated to a greater extent. When mussels were contaminated with mixed culture, vibrios appeared to predominate on E. coli, while no interference was observed between E. coli and S. typhi.


Assuntos
Bivalves/microbiologia , Escherichia coli/isolamento & purificação , Salmonella typhi/isolamento & purificação , Água do Mar/microbiologia , Vibrio/isolamento & purificação , Animais , Contagem de Colônia Microbiana , Meios de Cultura , Temperatura , Vibrio cholerae/isolamento & purificação , Microbiologia da Água
20.
New Microbiol ; 22(2): 139-50, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10322613

RESUMO

During the EOCUMM '94 cruise, 15 stations located in the Eolian Islands area (Southern Tyrrhenian Sea) were sampled to analyse the distributions of the total bacterioplankton densities and the heterotrophic viable bacteria counts on Marine Agar 2216. According to the TS (temperature-salinity) diagrams, obtained by processing the CTD (conductivity-temperature-depth) vertical profiles, the sampled stations were grouped in "hydrological clusters". The bacteriological variables, together with the chlorophyll a and the particulate organic carbon measures obtained during the same cruise were used to compare the stations of the same and different clusters. The results indicated that variabilities of the analysed microbial parameters were not obviously related to the hydrographic features of the sampling stations. This work is an attempt to verify the possibility of using microbial parameters to characterize the structure of the water column.


Assuntos
Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Ecossistema , Água do Mar/microbiologia , Microbiologia da Água , Análise de Variância , Animais , Carbono/análise , Clorofila/análise , Análise por Conglomerados , Contagem de Colônia Microbiana , Meios de Cultura , Itália , Modelos Estatísticos , Oceanos e Mares , Cloreto de Sódio , Estatísticas não Paramétricas , Temperatura
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