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1.
Science ; 373(6558): 1012-1016, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34446602

RESUMO

Materials with multiple superconducting phases are rare. Here, we report the discovery of two-phase unconventional superconductivity in CeRh2As2 Using thermodynamic probes, we establish that the superconducting critical field of its high-field phase is as high as 14 tesla, even though the transition temperature is only 0.26 kelvin. Furthermore, a transition between two different superconducting phases is observed in a c axis magnetic field. Local inversion-symmetry breaking at the cerium sites enables Rashba spin-orbit coupling alternating between the cerium sublayers. The staggered Rashba coupling introduces a layer degree of freedom to which the field-induced transition and high critical field seen in experiment are likely related.

2.
Eur J Clin Microbiol Infect Dis ; 36(9): 1685-1690, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28429163

RESUMO

Empiric initial antibiotic therapy of bacterial infections is based primarily upon the susceptibility of the most common causative pathogens. The purpose of this study was to provide susceptibility data on six bacterial species known to cause ear, nose and throat (ENT) infections. A total of 1066 isolates collected during a nationwide laboratory-based surveillance study were analysed. All Streptococcus pyogenes isolates were penicillin (PEN)-susceptible, indicating that natural penicillins can still be recommended as the first-line treatment for group A streptococcal tonsillopharyngitis. Of the S. pneumoniae isolates, 92.9% were PEN-susceptible and of the Haemophilus influenzae isolates, 89.7% were amoxicillin-susceptible, retaining aminopenicillins as the first-line treatment for acute otitis media (AOM) and acute rhinosinusitis (ARS), in case antibiotic therapy is considered. In contrast, cefuroxime axetil seems less likely to be suitable for the treatment of AOM or ARS, as all Moraxella catarrhalis and >99% of the H. influenzae isolates were categorised as intermediate or resistant. The susceptibility rates of Pseudomonas aeruginosa were 97-100% for the drugs tested, except for the fluoroquinolones (87.6%). Overall, bacterial isolates from outpatients presenting with ENT infections showed low frequencies of resistance in Germany. However, given the emergence of multidrug resistance to standard antibiotics in Escherichia coli and other pathogens, inappropriate use of broad-spectrum antibiotics for the treatment of ENT infections has to be avoided.


Assuntos
Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Otite/epidemiologia , Otite/microbiologia , Faringite/epidemiologia , Faringite/microbiologia , Rinite/epidemiologia , Rinite/microbiologia , Anti-Infecciosos/farmacologia , Serviços de Saúde Comunitária , Alemanha/epidemiologia , Humanos , Testes de Sensibilidade Microbiana
3.
Allergy ; 68(6): 724-31, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23621350

RESUMO

BACKGROUND: Recombinant allergens offer a tool for improving specific immunotherapy (SIT). OBJECTIVE: To find the optimal dose of a new hypoallergenic folding variant of recombinant Bet v 1 (rBet v 1-FV) as SIT for patients with birch pollen allergy. METHODS: Before SIT, thirty-seven adult patients were exposed for eight hours in an environmental exposure chamber (EEC) to birch pollen at an average concentration of 3500 ± 500 grains/m(3) , then randomized to four maintenance dose groups of rBet v 1-FV and one placebo group: 20 µg (n = 7), 80 µg (n = 8), 160 µg (n = 7), 320 µg (n = 8), and placebo (n = 7). Patients were treated for 10 weeks with weekly injections and then re-exposed in the EEC. The optimal dose for SIT was assessed using efficacy results from the EEC, IgG responses, and tolerability. RESULTS: Thirty-six patients were evaluable for efficacy assessment. The total symptom score significantly decreased in all active groups compared with placebo (-18.8% for placebo patients; -71.9%, P = 0.0022 for 20 µg; -75.6%, P = 0.0007 for 80 µg; -81.8%, P = 0.0009 for 160 µg; -78.3%, P = 0.0003 for 320 µg). IgG1 increased significantly in all active groups compared to placebo. All four active doses were well tolerated, no serious adverse event occurred; two Grade II reactions, according to EAACI classification, were observed, one in each of the 160- and 320-µg groups. CONCLUSIONS: Considering efficacy, immunological response, and tolerability, a maintenance dose of 80 µg of rBet v 1-FV appears to be the ideal dose for allergen immunotherapy in birch pollen allergic patients.


Assuntos
Alérgenos/administração & dosagem , Antígenos de Plantas/administração & dosagem , Dessensibilização Imunológica/métodos , Rinite Alérgica Sazonal/terapia , Adolescente , Adulto , Idoso , Alérgenos/uso terapêutico , Análise de Variância , Antígenos de Plantas/uso terapêutico , Câmaras de Exposição Atmosférica , Dessensibilização Imunológica/instrumentação , Relação Dose-Resposta Imunológica , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Análise dos Mínimos Quadrados , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Rinite Alérgica Sazonal/imunologia , Resultado do Tratamento , Adulto Jovem
4.
J Vet Pharmacol Ther ; 35(6): 571-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22276681

RESUMO

Pradofloxacin (PRA), a novel veterinary 8-cyano-fluoroquinolone (FQ), is active against Staphylococcus pseudintermedius, the primary cause of canine pyoderma. An in vitro pharmacokinetic-pharmacodynamic model was used to compare the activities of PRA and marbofloxacin (MAR) against three clinical isolates of S. pseudintermedius and reference strain Staphylococcus aureus ATCC 6538. Experiments were performed involving populations of 10(10) CFU corresponding to an inoculum density of approximately 5 × 10(7) CFU/mL. The time course of free drug concentrations in canine serum was modelled, resulting from once daily standard oral dosing of 3 mg of PRA/kg and 2 mg of MAR/kg. In addition, experimentally high doses of 6 mg of PRA/kg and 16 mg of MAR/kg were tested against the least susceptible strain. Viable counts were monitored over 24 h. At concentrations associated with standard doses, PRA caused a faster and more sustained killing than MAR of all strains. The ratios of free drug under the concentration-time curve for 24 h over MIC and the maximum concentration of free drug over MIC were at least 90 and 26, and 8.5 and 2.1 for PRA and MAR, respectively. At experimentally high doses, PRA was superior to MAR in terms of immediate killing. Subpopulations with reduced susceptibility to either FQ did not emerge. We conclude that PRA is likely to be an efficacious therapy of canine staphylococcal infections.


Assuntos
Antibacterianos/farmacologia , Cães , Fluoroquinolonas/farmacologia , Modelos Biológicos , Staphylococcus/efeitos dos fármacos , Animais , Antibacterianos/farmacocinética , Área Sob a Curva , Fluoroquinolonas/farmacocinética , Meia-Vida , Testes de Sensibilidade Microbiana , Staphylococcus/classificação
5.
Horm Metab Res ; 43(12): 858-64, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22105476

RESUMO

Here we tested whether global histone modifications predict survival in organic hyperinsulinism and whether global histone modification pattern can be used to distinguish benign from malignant primary insulinoma. A tissue microarray (TMA) was built, using samples from 63 patients with organic hyperinsulinism. The TMA was classified according to the WHO classification of 2004 [WHO 1A: benign insulinoma (wdPET); WHO 1B: unknown behavior (wdPETub); WHO 2/3: malignant insulinoma (wdPEC/pdPEC)]. The TMA consisted of tissue cores from islands of Langerhans, primary insulinomas, lymph node metastases, and hepatic metastases. Immunohistochemistry was performed on consecutive TMA slides with antibodies against H3K9Ac, H3K18Ac, H4K12Ac, H3K4diMe, and H4R3diMe. The Remmele immunoreactive scoring system was used to classify the staining. The IHC staining results were correlated to the WHO-classification of 2004 as well as to clinical follow-up data (mean: 107 months; range: 1-312 months). A nuclear staining pattern was observed for all antibodies directed against histone H3 and H4 acetylation/methylation sites. We observed significant differences in the distribution of the medians across all investigated tissue types (H3K9Ac, p=0.004; H3K18Ac, p=0.001; H4K12Ac, p=0.006; H4R3diMe, p=0.002) except for H3K4diMe (p=0.183). Correlation of the histone modification with the WHO-classification and clinical follow-up data, showed in the dichotomized groups ["low" (score 0-3), "moderate" (4-7) vs. "high" (≥8)] that patients with lower H3K18Ac levels ("low + moderate") had a significantly decreased relapse-free survival vs. patients with high H3K18Ac levels (p=0.038). The WHO classification and age were also of significant prognostic impact upon univariate analysis. A backwards Cox proportional hazards model revealed the independent prognostic effekt of H3K18Ac levels. Our data revealed low K18 acetylation levels of histone H3 as independent prognostic factor in organic hyperinsulinism. This result warrants validation with independent data sets of organic hyperinsulinism, but is in line with several previous studies in different cancer entities. The broad applicability of this potential biomarker might lead to standardized diagnostic tests in near future and may help to manage insulinoma patients more effectively.


Assuntos
Histonas/metabolismo , Hiperinsulinismo/diagnóstico , Hiperinsulinismo/metabolismo , Processamento de Proteína Pós-Traducional , Idoso , Feminino , Humanos , Hiperinsulinismo/classificação , Hiperinsulinismo/patologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Coloração e Rotulagem , Organização Mundial da Saúde
6.
Horm Metab Res ; 43(12): 865-71, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22105477

RESUMO

PTEN (phosphatase and tensin homologue deleted from chromosome 10) is a well established tumor suppressor gene, which was cloned to chromosome 10q23. PTEN plays an important role in controlling cell growth, apoptosis, cell adhesion, and cell migration. In various studies, a genetic change as well as loss of PTEN expression by different carcinomas has been described. To date, the role of PTEN as a differentiation marker for neuroendocrine tumors (NET) and for the loss of PTEN expression is still unknown. It is assumed that loss of PTEN expression is important for tumor progression of NETs. We hypothesize that PTEN might be used as a new prognostic marker. We report 38 patients with a NET of the pancreas. Tumor tissues were surgically resected, fixed in formalin, and embedded in paraffin. PTEN expression was evaluated by immunohistochemistry and was correlated with several clinical and pathological parameters of each individual tumor. After evaluation of our immunohistochemistry data using a modified Remmele Score, a widely accepted method for categorizing staining results for reports and statistical evaluation, staining results of PTEN expression were correlated with the clinical and pathological parameters of each individual tumor. Our data demonstrates a significant difference in survival with existence of lymph node or distant metastases. Negative patients show a significant better survival compared with positive patients. Furthermore, we show a significant difference between PTEN expression and WHO or TNM classification. Taken together, our data shows a positive correlation between WHO classification and the new TNM classification of NETs, and loss of PTEN expression as well as survival. These results strongly implicate that PTEN might be helpful as a new prognostic factor.


Assuntos
Tumores Neuroendócrinos/enzimologia , PTEN Fosfo-Hidrolase/deficiência , Neoplasias Pancreáticas/enzimologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tumores Neuroendócrinos/classificação , Tumores Neuroendócrinos/patologia , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias Pancreáticas/classificação , Neoplasias Pancreáticas/patologia , Análise de Sobrevida , Organização Mundial da Saúde , Adulto Jovem
7.
Allergy ; 66(5): 629-36, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21261656

RESUMO

BACKGROUND: Combined symptom and medication scores (SMS) are recommended as primary endpoints in clinical trials. Several SMS have been created, but none has been formally validated. OBJECTIVE: To evaluate the validity of the 'Allergy-Control-SCORE© (ACS)', a novel instrument to assess patient's allergy severity by recording symptoms and rescue medication. METHODS: One hundred and twenty-one consenting subjects (age 18-65 year), including 81 patients with allergic rhino-conjunctivitis and/or asthma and 40 healthy controls, participated in the study. They recorded daily nasal, eye, and lung symptoms using a 4-point scale (none, mild, moderate, and severe) and use of anti-symptomatic medication. Pollen counts were monitored during the study period. Symptom and medication scores values were compared to global allergy severity, quality of life, and allergy-related medical consultations. Feasibility was tested through a questionnaire on comprehensibility, easiness of use, and completeness. Retest reliability was assessed by testing consistency, in relation to pollen exposure, and for values recorded during each of 2 consecutive weeks. RESULTS: Convergent reliability analysis indicated a highly significant correlation between ACS© and global allergy severity (P < 0.0001), quality of life (P < 0.0001), and allergy-related medical consultations (P < 0.0001). Scores were highly related to pollen counts. Allergy-Control-SCORE© showed a good retest reliability (r = 0.81; P < 0.0001) and discriminated extremely well between patients with allergy and healthy controls (6.1 ± 4.8 vs 0.2 ± 0.5; t = 10.82; P < 0.0001) with a sensitivity of 97% and a specificity of 87%. Study participants evaluated the feasibility of the SMS as excellent. CONCLUSIONS: Allergy-Control-SCORE© is a valid and reliable instrument to assess allergy severity in clinical trials and observational studies of respiratory allergic diseases.


Assuntos
Ensaios Clínicos como Assunto/métodos , Hipersensibilidade/tratamento farmacológico , Índice de Gravidade de Doença , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Conjuntivite Alérgica , Humanos , Hipersensibilidade/patologia , Pessoa de Meia-Idade , Pólen , Sensibilidade e Especificidade , Adulto Jovem
8.
Curr Med Res Opin ; 23(10): 2387-94, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17714607

RESUMO

OBJECTIVE: To compare a step-down approach in well-controlled asthma patients, as recommended by treatment guidelines, from fluticasone propionate 250 microg twice daily (FP250 BID), or equivalent, to ciclesonide 160 microg once daily (CIC160 OD) with continued FP250 BID treatment. RESEARCH DESIGN AND METHODS: Patients with well-controlled asthma prior to study entry were included in two identical, randomized, double-blind, double-dummy, parallel-group studies. After a 2-week run-in period with FP250 BID, patients were randomized to CIC160 OD (n = 58) or FP250 BID (n = 53) for 12 weeks. Primary endpoints were percentage of days with asthma control, asthma symptom-free days, rescue medication-free days and nocturnal awakening-free days. Secondary endpoints included lung function variables, asthma symptom scores, rescue medication use and asthma exacerbations. Safety variables were also recorded. RESULTS: Patients had >or= 97% of days with asthma control, 98% asthma symptom-free days and 100% of days free from rescue medication use and nocturnal awakenings in both treatment groups (median values). There were no significant between-treatment differences for any of the primary or secondary efficacy variables. Overall, 42 treatment-emergent adverse events (TEAEs) were reported in the CIC160 OD group and 49 TEAEs were reported in the FP250 BID group. There were no clinically relevant changes from baseline in the safety variables in either treatment group. CONCLUSIONS: Patients well controlled on FP250 BID, or equivalent, who were stepped down to CIC160 OD, maintained similar asthma control compared with patients who received continued treatment standardized to FP250 BID.


Assuntos
Androstadienos/uso terapêutico , Antialérgicos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Asma/tratamento farmacológico , Pregnenodionas/uso terapêutico , Adolescente , Adulto , Idoso , Androstadienos/administração & dosagem , Antialérgicos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Método Duplo-Cego , Esquema de Medicação , Feminino , Fluticasona , Humanos , Masculino , Pessoa de Meia-Idade , Pregnenodionas/administração & dosagem , Resultado do Tratamento
10.
Clin Microbiol Infect ; 11(1): 39-46, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15649302

RESUMO

A surveillance study was performed throughout Germany from November 2001 to June 2002 to assess the prevalence of linezolid-resistant isolates among Gram-positive bacteria from routine susceptibility data and to compare the in-vitro activity of linezolid to that of other antibacterial agents. Each of 86 laboratories provided routine susceptibility data for 100 consecutive isolates. Most laboratories (c. 60%) used the disk diffusion test. Laboratories were also requested to send a representative sample of their isolates, as well as all isolates reported as intermediate or resistant to linezolid, to a reference laboratory for MIC determination. Susceptibility data for 8594 isolates were evaluated. Sites of infection were skin and soft tissue (29.9%), upper and lower respiratory tract (19.1%), foreign body or catheter (10.5%), or urinary tract (9.8%). Routine linezolid susceptibility data were reported for 6433 isolates. The prevalence of linezolid resistance, as reported to the clinician, was 0.4% in Staphylococcus aureus, 0.3% in Staphylococcus epidermidis, 2.9% in Enterococcus faecalis, 2.3% in Enterococcus faecium, 1.4% in Streptococcus pyogenes and 2.9% in Streptococcus agalactiae. Linezolid resistance was not detected in Streptococcus pneumoniae or in viridans group streptococci. Sixty-nine of 115 isolates reported as intermediate or resistant to linezolid were retested, but none was resistant to linezolid. Linezolid exhibited excellent in-vitro activity against representative isolates of the six most frequently encountered species (MIC90, 1-2 mg/L). The prevalence of resistance to linezolid was very low in Germany. Organisms reported as linezolid-resistant should be retested, either in the same laboratory with an alternative method or in a reference laboratory.


Assuntos
Acetamidas/farmacologia , Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana , Infecções por Bactérias Gram-Positivas/epidemiologia , Cocos Gram-Positivos/efeitos dos fármacos , Oxazolidinonas/farmacologia , Vigilância da População , Adulto , Idoso , Antibacterianos/farmacologia , Feminino , Alemanha/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Linezolida , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade
11.
Artigo em Inglês | MEDLINE | ID: mdl-12726850

RESUMO

Kavain metabolism in humans was the target of this current investigation. In the present study a high-performance liquid chromatographic (HPLC-DAD) assay method for the simultaneous determination of kavain and its main metabolites (p-hydroxykavain, p-hydroxy-5,6-dehydrokavain and p-hydroxy-7,8-dihydrokavain) in serum and urine was developed and validated. The metabolites were mainly excreted in the form of their conjugates. All kavain metabolites were detectable in serum and urine, except for p-hydroxy-7,8-dihydrokavain, which was found in urine only. Confirmation of the results and identification of the metabolites were performed by LC-MS or LC-MS-MS. Kinetics of kavain and its metabolites in serum were investigated after administration of a single oral dose (800 mg kavain). Within 1 and 4 h after uptake, the serum concentrations ranged between 40 and 10 ng/ml for kavain, 300 and 125 ng/ml for p-hydroxykavain, 90 and 40 ng/ml for o-desmethyl-hydroxy-5,6-dehydrokavain, and 50 and 30 ng/ml for 5,6-dehydrokavain.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Pironas/farmacocinética , Administração Oral , Biotransformação , Humanos , Pironas/administração & dosagem , Pironas/sangue , Pironas/urina , Padrões de Referência , Reprodutibilidade dos Testes
14.
Intensive Care Med ; 27(9): 1526-31, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11685347

RESUMO

OBJECTIVE: To assess the effects of C1 inhibitor (INH) administration and r-SP-C surfactant application on oxygenation and lung histology in an acute respiratory distress syndrome model. DESIGN AND SETTING: Randomized, controlled experimental study in an animal research laboratory. MATERIAL: 36 adult male Sprague-Dawley rats. INTERVENTIONS: Animals were subjected to repetitive lung lavage. Four experimental groups and two control groups were studied: groups 1 and 2 served as controls. Animals of groups 3-6 received 200 U/kg body weight C1-INH (group 3), 25 mg/kg r-SP-C surfactant (group 4) or both (group 5) at 60 min postlavage (pl). Animals of group 6 were treated with 200 U/kg C1-INH1 at 10 min pl. Animals of group 1 were killed 60 min (min) pl, animals of groups 2-6 were killed at 210 min pl. Thereafter the lungs were excised for histological examination. MEASUREMENTS AND RESULTS: Hyaline membrane formation, intra-alveolar neutrophil (PMN) accumulation and intra-alveolar/perivascular haemorrhage were graded semiquantitatively (0-4). Blood gases were determined 120, 150, 180 and 210 min pl. At 210 min pl pO(2) in group 4 (456+/-74 mmHg) and group 5 (387+/-155 mmHg) was significantly higher than in controls (72+/-29 mmHg) or after C1-INH monotherapy (group 3: 120+/-103, group 6: 63+/-12 mmHg). PMN infiltration after C1-INH monotherapy was significantly less severe than in controls. The combination of r-SP-C surfactant and C1-INH led to significantly lower PMN infiltration than surfactant monotherapy. CONCLUSION: In this lavage-induced acute respiratory distress syndrome model the administration of C1-INH might be followed by a higher clinical efficacy of exogenously supplied recombinant SP-C surfactant.


Assuntos
Proteínas Inativadoras do Complemento 1/uso terapêutico , Modelos Animais de Doenças , Consumo de Oxigênio/efeitos dos fármacos , Proteolipídeos/uso terapêutico , Surfactantes Pulmonares/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/metabolismo , Animais , Biópsia , Gasometria , Proteínas Inativadoras do Complemento 1/farmacologia , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Masculino , Neutrófilos , Proteolipídeos/farmacologia , Surfactantes Pulmonares/farmacologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/patologia , Índice de Gravidade de Doença , Fatores de Tempo
15.
J Clin Microbiol ; 39(10): 3724-6, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11574602

RESUMO

The prevalence of integrons in five enterobacterial species was analyzed in 900 blood culture isolates from 1993, 1996, and 1999. Remarkably, the prevalence increased from 4.7% in 1993 to 9.7% in 1996 and finally to 17.4% in 1999 (P < 0.01). Within 7 years the combined percentage of P1 strong promoters and P1 weak plus P2 active promoters with high transcription efficacies has increased from 23.1 to 33.3 and finally 60% (P < 0.05).


Assuntos
Elementos de DNA Transponíveis , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/genética , Hospitais Universitários , Integrases/genética , Sangue/microbiologia , Meios de Cultura , Enterobacter/genética , Enterobacter/isolamento & purificação , Enterobacteriaceae/isolamento & purificação , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Alemanha/epidemiologia , Humanos , Klebsiella/genética , Klebsiella/isolamento & purificação , Prevalência
18.
J Clin Microbiol ; 39(5): 1928-31, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11326015

RESUMO

In a prospective multicenter study (1996 to 1999), 156 episodes of bacteremic streptococcal infections of neutropenic patients were evaluated. Streptococcus oralis (26.3%), S. pneumoniae (26.3%), S. agalactiae (11.5%), S. mitis (9%), and S. pyogenes (5.8%) were the predominant species. Four strains (2.6%) were found to be intermediately resistant to penicillin. One strain (0.6%) was found to be highly resistant to penicillin (MIC, 8 mg/liter). Reduced susceptibility to penicillin was detected among S. oralis (14.6%), S. mitis (7.1%), and S. pneumoniae (4.9%) isolates but was not recorded among S. agalactiae and S. pyogenes. Resistance rates and intermediate resistance rates for other antimicrobials were as follows (all species): amoxicillin, 1.3 and 3.2%; erythromycin, 16 and 2.6%; clindamycin, 5.8 and 0%; ciprofloxacin, 1.9 and 7.7%. Quinupristin-dalfopristin showed good in vitro activity against most streptococcal isolates (MIC at which 50% of the isolates were inhibited [MIC(50)], 0.5 mg/liter; MIC(90), 1 mg/liter, MIC range, 0.25 to 4 mg/liter).


Assuntos
Antibacterianos/farmacologia , Bacteriemia/microbiologia , Neutropenia/complicações , Infecções Estreptocócicas/microbiologia , Streptococcus/efeitos dos fármacos , Virginiamicina/farmacologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/epidemiologia , Sangue/microbiologia , Criança , Pré-Escolar , Resistência Microbiana a Medicamentos , Feminino , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Prospectivos , Infecções Estreptocócicas/epidemiologia , Streptococcus/classificação , Streptococcus/isolamento & purificação
19.
Proc Natl Acad Sci U S A ; 97(26): 14438-43, 2000 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-11095731

RESUMO

We use analyses of phylogeographic population structure across a suite of 12 mammalian, avian, amphibian, and reptilian species and species-groups to assess the role of Late Miocene to Pleistocene geological history in the evolution of a distinct Baja California Peninsular Desert biota. Comparative examination of phylogroup distributions provides support for previously hypothesized vicariant events produced by: a middle Pleistocene midpeninsular seaway, a late Pliocene northward transgression of the Sea of Cortéz, and a Pliocene seaway across the southern peninsular Isthmus of La Paz. Most of this phylogeographic architecture is cryptically embedded within widespread taxonomic species and species-groups, such that the unique evolutionary history of the Peninsular Desert has been obscured and ignored. The Peninsular Desert can no longer be considered a subset of the Sonoran Desert-it is a separate regional desert with its own unique evolutionary history, ecological arena, and conservation value.


Assuntos
Anfíbios/genética , Aves/genética , Evolução Molecular , Répteis/genética , Roedores/genética , Anfíbios/classificação , Animais , Sequência de Bases , Aves/classificação , California , DNA Complementar , DNA Mitocondrial/análise , DNA Mitocondrial/classificação , Demografia , Fósseis , México , Dados de Sequência Molecular , Filogenia , Répteis/classificação , Roedores/classificação
20.
Mol Phylogenet Evol ; 17(2): 145-60, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11083930

RESUMO

Phylogeographic relationships among 26 populations from throughout the geographic range of the Peromyscus eremicus species group are described based on sequence data for a 699-bp fragment of the mitochondrial DNA COIII gene. Distance, maximum-likelihood, and maximum-parsimony analyses of phylogenetic trees generated under four separate character-weighting strategies and representing five alternative biogeographic hypotheses revealed the existence of a cryptic species (Peromyscus fraterculus, previously included under P. eremicus) on the Baja California Peninsula and adjacent southwestern California and two distinct forms of P. eremicus, one from the Mojave, Sonoran, and northwestern Chihuahuan regional deserts (West) and one from the remainder of the Chihuahuan Desert (East). Distinctiveness of P. fraterculus is supported by previous morphometric and allozyme analyses, including comparisons with neighboring P. eremicus and parapatric P. eva, with which P. fraterculus shares a sister taxon relationship. Divergence of the eva + fraterculus, West + East eremicus, and P. merriami haplotype lineages likely occurred in the late Neogene (3 Ma), in response to northern extension of the Sea of Cortéz and elevation of the Sierra Madre Occidental; divergence of eva from fraterculus is concordant with the existence of a trans-Peninsular seaway during the Pleistocene (1 Ma); and divergence of West from East eremicus occurred during the Pleistocene pluvial-interpluvial cycles, but well before the Wisconsinan glacial interval. The sequence of divergence within the eremicus species group and causal association of geological events of the Neogene and Holocene provide a working hypothesis against which phylogeographic patterns among other arid-adapted species of the warm regional deserts of North America may be compared.


Assuntos
Clima Desértico , Peromyscus/genética , Filogenia , Animais , DNA/genética , DNA Mitocondrial/química , DNA Mitocondrial/genética , Evolução Molecular , Variação Genética , Geografia , Haplótipos , Dados de Sequência Molecular , América do Norte , Peromyscus/classificação , Proteínas de Plantas/genética , Análise de Sequência de DNA
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