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1.
Lett Appl Microbiol ; 75(3): 578-587, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34687564

RESUMEN

Broth microdilution assays were used to determine minimum inhibitory concentrations (MICs) and fractional inhibitory concentration indices (FICIs) of tea tree oil (TTO), tobramycin, colistin and aztreonam (ATM) against clinical cystic fibrosis-associated Pseudomonas aeruginosa (CFPA) isolates (n = 20). The minimum biofilm eradication concentration (MBEC) and fractional biofilm eradication concentration index (FBECI) were also determined using a similar microbroth dilution checkerboard assay, with biofilms formed using the MBEC device® . TTO was effective at lower concentrations against multidrug-resistant (MDR) CFPA isolates (n = 3) in a biofilm compared to in a planktonic state (MBEC 18·7-fold lower than MIC). CFPA within biofilm was less susceptible to ATM, colistin and tobramycin compared to planktonic cells (MBEC 6·3-fold, 9·3-fold, and 2·1-fold higher than MIC respectively). All combinations of essential oil and antibiotic showed indifferent relationships (FICI 0·52-1·72) when tested against planktonic MDR CFPA isolates (n = 5). Against CFPA isolates (n = 3) in biofilm, combinations of TTO/aztreonam and TTO/colistin showed indifferent relationships (mean FBECI 0·85 and 0·60 respectively), whereas TTO/tobramycin showed a synergistic relationship (mean FBECI 0·42). The antibiofilm properties of TTO and the synergistic relationship seen between TTO and tobramycin against CFPA in vitro make inhaled TTO a promising candidate as a potential therapeutic agent.


Asunto(s)
Fibrosis Quística , Melaleuca , Aceites Volátiles , Aceite de Árbol de Té , Antibacterianos/farmacología , Aztreonam/farmacología , Biopelículas , Colistina/farmacología , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/farmacología , Pseudomonas aeruginosa , , Aceite de Árbol de Té/farmacología , Tobramicina/farmacología , Árboles
2.
Water Res X ; : 100063, 2020 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-32875284

RESUMEN

Cities are wrestling with the practical challenges of transitioning urban water services to become water sensitive; capable of enhancing liveability, sustainability, resilience and productivity in the face of climate change, rapid urbanisation, degraded ecosystems and ageing infrastructure. Indicators can be valuable for guiding actions for improvement, but there is not yet an established index that measures the full suite of attributes that constitute water sensitive performance. This paper therefore presents the Water Sensitive Cities (WSC) Index, a new benchmarking and diagnostic tool to assess the water sensitivity of a municipal or metropolitan city, set aspirational targets and inform management responses to improve water sensitive practices. Its 34 indicators are organised into seven goals: ensure good water sensitive governance, increase community capital, achieve equity of essential services, improve productivity and resource efficiency, improve ecological health, ensure quality urban spaces, and promote adaptive infrastructure. The WSC Index design as a quantitative framework based on qualitative rating descriptions and a participatory assessment methodology enables local contextual interpretations of the indicators, while maintaining a robust universal framework for city comparison and benchmarking. The paper demonstrates its application on three illustrative cases. Rapid uptake of the WSC Index in Australia highlights its value in helping stakeholders develop collective commitment and evidence-based priorities for action to accelerate their city's water sensitive transition. Early testing in cities in Asia and the Pacific has also showed the potential of the WSC Index internationally.

3.
Water Res ; 186: 116411, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32949887

RESUMEN

Cities are wrestling with the practical challenges of transitioning urban water services to become water sensitive; capable of enhancing liveability, sustainability, resilience and productivity in the face of climate change, rapid urbanisation, degraded ecosystems and ageing infrastructure. Indicators can be valuable for guiding actions for improvement, but there is not yet an established index that measures the full suite of attributes that constitute water sensitive performance. This paper therefore presents the Water Sensitive Cities (WSC) Index, a new benchmarking and diagnostic tool to assess the water sensitivity of a municipal or metropolitan city, set aspirational targets and inform management responses to improve water sensitive practices. Its 34 indicators are organised into seven goals: ensure good water sensitive governance, increase community capital, achieve equity of essential services, improve productivity and resource efficiency, improve ecological health, ensure quality urban spaces, and promote adaptive infrastructure. The WSC Index design is a quantitative framework based on qualitative rating descriptions and a participatory assessment methodology, enabling local contextual interpretations of the indicators while maintaining a robust universal framework for city comparison and benchmarking. The paper demonstrates its application on three illustrative cases. Rapid uptake of the WSC Index in Australia highlights its value in helping stakeholders develop collective commitment and evidence-based priorities for action to accelerate their city's water sensitive transition. Early testing in cities in Asia, the Pacific and South Africa has also showed the potential of the WSC Index internationally.


Asunto(s)
Ecosistema , Agua , Australia , Ciudades , Sudáfrica
4.
Arch Gynecol Obstet ; 301(5): 1199-1205, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32303887

RESUMEN

PURPOSE: The aim of our study was to compare the maternal arterial stiffness in pregnant women with diabetic disease, hypertension and those with normal pregnancies. METHODS: A cross-sectional study was performed involving 65 pregnant women with diabetic disease (DD group), 26 pregnant women with hypertension (RR group) and 448 women with normal pregnancies (control group). The augmentation index (AIx) and the pulse wave velocity (PWV) of the right carotid artery were assessed using non-invasive sonographic wave intensity analysis. Furthermore, the reliability of the measurements was evaluated in 21 healthy women. RESULTS: Compared with the controls, the AIx and PWV were increased in the DD group [11.0 (interquartile range, IQR 7.3, 15.2) vs. 5.7 (IQR 2.4, 9.3), P < 0.001; 5.7 (IQR 5.1, 6.4) vs. 5.2 (IQR 4.6, 6.1), P = 0.001; respectively] and the RR group [9.3 (IQR 6.6, 11.5) vs. 5.7 (IQR 2.4, 9.3), P < 0.001; 7.1 (6.3, 7.9) vs. 5.2 (IQR 4.6, 6.1), P < 0.001; respectively]. The intraclass and interclass correlation coefficients were good to excellent for the AIx (ICC: 0.91, P < 0.001 and 0.74, P < 0.002; respectively) and PWV measurements (ICC: 0.71, P < 0.004 and 0.70, P < 0.005; respectively). CONCLUSION: Pregnancies complicated by diabetic disease or hypertension are associated with increased maternal arterial stiffness. The importance of wave intensity analysis needs to be verified and larger studies are needed to establish both normal and cutoff values that may be relevant for clinical decisions.


Asunto(s)
Arterias/fisiopatología , Velocidad del Flujo Sanguíneo/fisiología , Diabetes Gestacional/fisiopatología , Hipertensión Inducida en el Embarazo/fisiopatología , Flujo Pulsátil/fisiología , Análisis de la Onda del Pulso/métodos , Rigidez Vascular/fisiología , Adulto , Estudios de Casos y Controles , Estudios Transversales , Diabetes Mellitus/epidemiología , Diabetes Mellitus/fisiopatología , Diabetes Gestacional/epidemiología , Femenino , Humanos , Hipertensión/epidemiología , Hipertensión Inducida en el Embarazo/epidemiología , Persona de Mediana Edad , Embarazo , Reproducibilidad de los Resultados , Factores de Riesgo , Ultrasonografía
5.
J Assist Reprod Genet ; 37(4): 953-962, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32130614

RESUMEN

PURPOSE: To determine whether gestational carrier (GC) in vitro fertilization (IVF) cycles (commissioned cycles) for same-sex or single male intended parents have an increased incidence of adverse perinatal outcomes compared with spontaneous cycles in the same GCs. DESIGN: GC singleton pregnancies were identified from a database of 895 commissioned cycles from a large fertility center. Of these, 78 commissioned cycles met inclusion and exclusion criteria and were compared with 71 spontaneous cycles by the same GCs. The primary outcome was the composite score for adverse perinatal outcomes. Secondary outcomes included mode of delivery, birthweight, and gestational age. Chi-square test of association and Mann-Whitney U tests were used to compare categorical and continuous variables between the cohorts, respectively. Logistic and linear regressions controlling for GC age were constructed to determine the influence of GC cycle type on adverse perinatal outcomes. RESULTS: Commissioned cycles were significantly associated with adverse perinatal outcomes (25.6% vs. 9.9%; p = 0.02) and lower average gestational age (38.7 ± 1.5 vs. 39.4 ± 0.9; p < 0.001) compared with spontaneous cycles. Commissioned cycle increased the likelihood of adverse perinatal outcomes (OR 3.3; p = 0.03) and was a significant independent predictor of a lower average gestational age (ß = 0.897; p < 0.001). There were no significant differences in the incidence of vaginal deliveries or cesarean sections between commissioned and spontaneous cycles. CONCLUSIONS: Commissioned cycles confer a greater incidence of composite perinatal complications and were independently associated with a lower average gestational age when compared with spontaneous pregnancies carried by the same GC despite a confirmed healthy uterine environment, sperm samples, and donor oocytes.


Asunto(s)
Fertilidad/fisiología , Fertilización In Vitro , Resultado del Embarazo , Madres Sustitutas , Adulto , Peso al Nacer , Cesárea , Transferencia de Embrión , Femenino , Fertilidad/genética , Edad Gestacional , Humanos , Recién Nacido , Masculino , Matrimonio , Inducción de la Ovulación/métodos , Atención Perinatal , Embarazo , Nacimiento Prematuro , Estudios Retrospectivos , Transferencia de un Solo Embrión
6.
J Lesbian Stud ; 23(2): 279-293, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30698080

RESUMEN

This article pays homage to the antique term "B.D. (bulldyke) Woman" of the 1920s and 1930s, at a moment when the rise of a universal queer subject threatens to erase specific lesbian histories. Characterized by an aggressive stance and an enormousness that confronts rather than merely protests, Black B.D. artists "stole" both masculinity and White privilege to accumulate power and cultural capital. B.D. is therefore a multilayered response to sexism, racism, and homophobia. This performance style is a product of outrage at the oppressive conditions that marked the legacy of slavery, to which B.D. blues must be viewed as a response rather than a more static sexual aesthetic style belonging to lesbian women. Such masculine bravado in Black women disrupted gender/sex alignments and notions of cisnormativity embedded in African American communities. In order to think through this historical legacy, I perform close readings of song lyrics performed by Gertrude "Ma" Rainey and Bessie Smith. The rejection of oppressive conditions occurs most acutely through the theme of travelling in songs that decenter racialized and heteronormative conceptions of home. Through this theme, Rainey and Smith expanded the phallic possibilities of their time period, and for the 2010s, these artists tamper with our staid notions of what gender, sex, and sexuality have meant in the past.


Asunto(s)
Identidad de Género , Homosexualidad Femenina/psicología , Minorías Sexuales y de Género/psicología , Adulto , Negro o Afroamericano/historia , Femenino , Historia del Siglo XX , Homosexualidad Femenina/historia , Humanos , Masculinidad , Minorías Sexuales y de Género/historia , Población Blanca/historia
7.
J Appl Microbiol ; 126(2): 468-479, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30412324

RESUMEN

AIMS: To investigate the mechanisms of action of natural products with bactericidal (cinnamon root powder, peppermint oil, trans-cinnamaldehyde, menthol and zingerone) or bacteriostatic (fresh garlic bulb extract, garlic clove powder, Leptospermum honey and allicin) activity against two Clostridium difficile strains. METHODS AND RESULTS: Bactericidal products significantly reduced intracellular ATP after 1 h (P ≤ 0·01), quantified using the BacTiter-Glo reagent, and damaged the cell membrane, shown by the leakage of both 260-nm-absorbing materials and protein, and the uptake of propidium iodide. Bacteriolysis was not observed, determined by measuring optical density of treated cell suspensions at 620-nm. The effect of three bacteriostatic products on protein synthesis was quantified using an Escherichia coli S30 extract system, with Leptospermum honey (16% w/v) showing significant inhibition (P < 0·01). Lastly, no products showed elevated minimum inhibitory concentrations against antimicrobial-resistant C. difficile, determined by broth microdilution. CONCLUSIONS: Cytoplasmic membrane damage was identified as a mechanism of action that may contribute to the activity of several natural products against C. difficile. SIGNIFICANCE AND IMPACT OF THE STUDY: This study describes the possible mechanisms of action of natural products against C. difficile, yet the efficacy in vivo to be determined.


Asunto(s)
Antibacterianos/farmacología , Productos Biológicos/farmacología , Clostridioides difficile/efectos de los fármacos , Extractos Vegetales/farmacología
8.
J Appl Microbiol ; 125(3): 710-723, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29675852

RESUMEN

AIMS: To investigate the effect of natural products on the spore cycle of Clostridium difficile in vitro. METHODS AND RESULTS: Twenty-two natural products were investigated using four C. difficile strains. Effects on sporulation, determined using microscopy and a conventional spore recovery assay, showed that fresh onion bulb extract (6·3% v v-1 ) and coconut oil (8% v v-1 ) inhibited sporulation in all four isolates by 66-86% and 51-88%, respectively, compared to untreated controls. Fresh ginger rhizome extract (25% v v-1 ) was also inhibitory, although to a lesser extent. Using a standard spore germination and outgrowth assay, germination was unaffected by the 22 products, whereas outgrowth was significantly reduced by artichoke extract (18·8 mg ml-1 ), fresh onion bulb extract (25% v v-1 ), Leptospermum honeys (8% w v-1 ) and allicin (75 mg ml-1 ; P < 0·01). Sporicidal activity, investigated using a standard plate recovery assay, was minimal. CONCLUSIONS: Three of the 22 natural products (13%) showed inhibitory effects on sporulation of C. difficile and six products (27%) reduced vegetative outgrowth of C. difficile. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows the potential of natural products to inhibit different stages of C. difficile sporulation and encourages further investigation in this field.


Asunto(s)
Antibacterianos/farmacología , Clostridioides difficile/efectos de los fármacos , Extractos Vegetales/farmacología , Esporas Bacterianas/efectos de los fármacos , Aceite de Coco/farmacología , Cynara scolymus , Pruebas de Sensibilidad Microbiana , Cebollas
10.
Artículo en Inglés | MEDLINE | ID: mdl-28630187

RESUMEN

The use of rapid diagnostic tests (RDTs) enhances antimicrobial stewardship program (ASP) interventions in optimization of antimicrobial therapy. This quasi-experimental cohort study evaluated the combined impact of an ASP/RDT bundle on the appropriateness of empirical antimicrobial therapy (EAT) and time to de-escalation of broad-spectrum antimicrobial agents (BSAA) in Gram-negative bloodstream infections (GNBSI). The ASP/RDT bundle consisted of system-wide GNBSI treatment guidelines, prospective stewardship monitoring, and sequential introduction of two RDTs, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and the FilmArray blood culture identification (BCID) panel. The preintervention period was January 2010 through December 2013, and the postintervention period followed from January 2014 through June 2015. The postintervention period was conducted in two phases; phase 1 followed the introduction of MALDI-TOF MS, and phase 2 followed the introduction of the FilmArray BCID panel. The interventions resulted in significantly improved appropriateness of EAT (95% versus 91%; P = 0.02). Significant reductions in median time to de-escalation from combination antimicrobial therapy (2.8 versus 1.5 days), antipseudomonal beta-lactams (4.0 versus 2.5 days), and carbapenems (4.0 versus 2.5 days) were observed in the postintervention compared to the preintervention period (P < 0.001 for all). The reduction in median time to de-escalation from combination therapy (1.0 versus 2.0 days; P = 0.03) and antipseudomonal beta-lactams (2.2 versus 2.7 days; P = 0.04) was further augmented during phase 2 compared to phase 1 of the postintervention period. Implementation of an antimicrobial stewardship program and RDT intervention bundle in a multihospital health care system is associated with improved appropriateness of EAT for GNBSI and decreased utilization of BSAA through early de-escalation.


Asunto(s)
Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Bacterias Gramnegativas/efectos de los fármacos , Adolescente , Programas de Optimización del Uso de los Antimicrobianos/métodos , Bacteriemia/microbiología , Cultivo de Sangre/métodos , Carbapenémicos/uso terapéutico , Humanos , Estudios Prospectivos , beta-Lactamas/uso terapéutico
11.
J Appl Microbiol ; 123(1): 92-103, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28489336

RESUMEN

AIMS: To investigate the antimicrobial activity of various natural products against Clostridium difficile in vitro. METHODS AND RESULTS: The antibacterial activity of 20 natural products was determined by the agar well diffusion and broth microdilution assays against four C. difficile strains, three comparator organisms and four gastrointestinal commensal organisms. Of the raw natural products, garlic juice had the highest activity. The most active processed products were peppermint oil and the four pure compounds trans-cinnamaldehyde, allicin, menthol and zingerone. Furthermore, Bacteroides species had similar susceptibility to C. difficile to most natural products; however, Lactobacillus casei was less susceptible. The combined effect of natural products with vancomycin or metronidazole was determined using the conventional checkerboard titration method and the fractional inhibitory concentration index was calculated. The results showed a possible synergism between trans-cinnamaldehyde and vancomycin and partial synergy between trans-cinnamaldehyde and metronidazole. CONCLUSIONS: The study indicates a range of antimicrobial activity of natural products against C. difficile and suggests that they may be useful as alternative or complementary treatments for C. difficile infection (CDI), particularly as most are able to be given orally. SIGNIFICANCE AND IMPACT OF THE STUDY: This study encourages further investigation of natural products for treatment of CDI.

12.
Arch Gynecol Obstet ; 294(2): 239-43, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26573013

RESUMEN

PURPOSE: To improve the outcome of fetuses with gastrochisis several studies evaluated prenatal predictors. But there are different guidelines established and therefore the prenatal care is not standardized. With our study we wanted to evaluate the outcome of fetuses with gastroschisis after modification of prenatal management strategies at the Department of Obstetrics and Gynecology of the University Hospital Münster. METHODS: In this explorative retrospective study of 39 fetuses with gastroschisis, we compare the clinical outcome between two management groups. In the first group (group 1, n = 14) prenatal indication for delivery was confirmed by a subjective evaluation of the small bowel diameter and the wall thickness without established cut-off values for these parameters. In the second group (group 2, n = 25) certain limits for the small bowel diameter (25 mm) and the wall thickness (2.5 mm) were used for fetal surveillance. RESULTS: Noticeable differences between the two groups regarding birth weight, weight centile, arterial pH, small bowel diameter, wall thickness, adverse bowel condition and re-operations could not be observed. In group 2, delivery was earlier (p = 0.011), and a lower rate of prenatal complications was observed (p = 0.016). CONCLUSION: To avoid adverse prenatal complications we recommend the observation of fetuses with gastroschisis by sonographic monitoring of the small bowel diameter and the wall thickness.


Asunto(s)
Gastrosquisis/diagnóstico por imagen , Enfermedades Intestinales/diagnóstico por imagen , Atención Prenatal/métodos , Ultrasonografía Prenatal/métodos , Femenino , Feto , Humanos , Intestino Delgado/diagnóstico por imagen , Embarazo , Estudios Retrospectivos , Ultrasonografía
13.
Clin Microbiol Infect ; 22(4): 381.e1-381.e8, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26711435

RESUMEN

Reactivation of persistent human adenoviruses (HAdVs) is associated with high morbidity and mortality in paediatric haematopoietic stem cell transplant (HSCT) recipients. Although invasive HAdV infections mainly arise from the gastrointestinal (GI) tract, the specific sites of HAdV persistence are not well characterised. We prospectively screened biopsies from 143 non-HSCT paediatric patients undergoing GI endoscopy and monitored serial stool specimens from 148 paediatric HSCT recipients for the presence of HAdV by real-time PCR. Persistence of HAdV in the GI tract was identified in 31% of children, with the highest prevalence in the terminal ileum. In situ hybridisation and immunohistochemistry identified HAdV persistence in lymphoid cells of the lamina propria, whereas biopsies from five transplant recipients revealed high numbers of replicating HAdV in intestinal epithelial cells. The prevalence of HAdV species, the frequencies of persistence in the GI tract and reactivations post transplant indicated a correlation of intestinal HAdV shedding pre-transplant with high risk of invasive infection. HAdV persistence in the GI tract is a likely origin of infectious complications in immunocompromised children. Intestinal lymphocytes represent a reservoir for HAdV persistence and reactivation, whereas the intestinal epithelium is the main site of viral proliferation preceding dissemination. The findings have important implications for assessing the risk of life-threatening invasive HAdV infections.


Asunto(s)
Adenovirus Humanos/aislamiento & purificación , Adenovirus Humanos/fisiología , Tracto Gastrointestinal/virología , Activación Viral , Infecciones por Adenoviridae , Adolescente , Biopsia , Niño , Preescolar , Heces/virología , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Huésped Inmunocomprometido , Lactante , Mucosa Intestinal/virología , Linfocitos/virología , Masculino , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa , Adulto Joven
14.
Int J Antimicrob Agents ; 45(2): 106-10, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25465857

RESUMEN

Over-the-counter acne treatments containing tea tree oil from the plant Melaleuca alternifolia are widely available, and evidence indicates that they are a common choice amongst those self-treating their acne. The aims of this review were to collate and evaluate the clinical evidence on the use of tea tree oil products for treating acne, to review safety and tolerability and to discuss the underlying modes of therapeutic action.


Asunto(s)
Acné Vulgar/tratamiento farmacológico , Aceite de Árbol de Té/uso terapéutico , Humanos , Aceite de Árbol de Té/efectos adversos , Aceite de Árbol de Té/farmacología
15.
J Perinatol ; 34(10): 774-80, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24811225

RESUMEN

OBJECTIVE: To evaluate the correlation between preterm delivery before 37 weeks of gestation and ultrasound elastography strain measurement of cervical stiffness. STUDY DESIGN: In this prospective study, 182 pregnant women were examined vaginally by ultrasound elastography from a mid-sagittal plane. Cervical length was measured and strain was calculated in four regions of interest on the anterior cervical lip. First, the software was validated by intraobserver variability. Second, strain and strain ratios were calculated with adjusted software presets and correlated to the outcome of spontaneous preterm delivery (sPTD). RESULT: A total of 8928 regions of interest (ROIs) and 6696 ratios were evaluated. The median gestational age at examination was 26 ± 6.1 weeks. A median maternal age of 33 ± 5.6 and a medial parity of 1 ± 0.9 were observed. Intra-Class-Correlation values in validation phase ranged from 0.893 to 0.967. The prevalence of sPTD was 11.9%. Strain ratio Rselective was identified as the best predictor of preterm delivery. Rselective values >0.89 were associated with preterm delivery with a sensitivity of 0.59 and a specificity of 0.86 (odds ratio=1.474 for an increase of 0.1 in Rselective; P=0.002). CONCLUSION: Ultrasound elastography strain measurement of cervical stiffness is correlated with the predictability of preterm delivery.


Asunto(s)
Cuello del Útero/diagnóstico por imagen , Trabajo de Parto Prematuro/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Adulto , Medición de Longitud Cervical , Maduración Cervical/fisiología , Cuello del Útero/fisiología , Estudios de Cohortes , Elasticidad/fisiología , Diagnóstico por Imagen de Elasticidad , Estudios de Evaluación como Asunto , Femenino , Edad Gestacional , Humanos , Recién Nacido , Modelos Logísticos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Embarazo , Atención Prenatal/métodos , Estudios Prospectivos , Adulto Joven
16.
J Ethnopharmacol ; 144(2): 293-9, 2012 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-23000168

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Eucalyptus kinos are tannin-rich, mostly red-coloured wood exudates. They have played an important role in the traditional medicines of Australian Aboriginal people and were also a valued source of antibacterial and astringent agents for early European settlers. MATERIALS AND METHODS: Nineteen different Eucalyptus kinos were collected and analysed for their total phenolics and total tannin content as well as their relative amounts of hydrolysable and condensed tannins. They were also classified in accordance with Maiden's traditional kino categories. Well plate diffusion assays using three Gram positive and two Gram negative bacteria and a yeast species were carried out to assess antimicrobial properties. RESULTS: The investigated kino samples differ strongly in their total phenolics and overall tannin as well as their relative hydrolysable and condensed tannin contents. All but one could be assigned to one of the traditional Maiden kino classes. The samples, in particular those collected from Corymbia maculata and Eucalyptus ficifolia, demonstrated a strong antibacterial activity towards Gram positive bacteria but were inactive against the Gram negative strains and the yeast. No obvious correlation seems to exist between a particular Maiden class and antibacterial activity but there is a positive correlation between total phenolics/tannin content and antibacterial effect although two of the investigated kinos (Eucalyptus flocktoniae and Eucalyptus sargentii) deviated from this trend. The relative amounts of hydrolysable and condensed tannins in a kino sample do not seem to determine the antibacterial effect. CONCLUSION: Eucalpytus kinos present an interesting class of natural products which should be investigated further, not only to contribute to the growing field of tannin chemistry but to also learn more about the individual role played by the various hydrolysable and condensed tannins that determine a kino's antibacterial activity and to contribute to a better understanding of the use of some of these kinos in traditional systems of medicine. In particular samples like Eucalyptus flocktoniae kino, which recorded a higher antibacterial activity than predicted based on total tannin content, warrant more detailed chemical and antimicrobial analyses.


Asunto(s)
Antibacterianos/farmacología , Eucalyptus , Extractos Vegetales/farmacología , Taninos/farmacología , Bacterias/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/análisis , Taninos/análisis , Madera
17.
J Appl Microbiol ; 108(5): 1534-43, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19811569

RESUMEN

AIMS: The aim of this study was to determine the spectrum of antimicrobial activity of 11 samples of stingless bee honey compared to medicinal, table and artificial honeys. METHODS AND RESULTS: Activity was assessed by agar diffusion, agar dilution, broth microdilution and time-kill viability assays. By agar dilution, minimum inhibitory concentration (MIC) ranges were 4% to >10% (w/v) for Gram-positive bacteria, 6% to >16% (w/v) for Gram-negative bacteria and 6% to >10% (w/v) for Candida spp. By broth microdilution, all organisms with the exception of Candida albicans and Candida glabrata were inhibited at 3 log for Pseudomonas aeruginosa and <1 log for C. albicans. Similar treatment with each control honey resulted in decreases of <1 log for all organisms. CONCLUSIONS: Stingless bee honey has broad-spectrum antibacterial activity although activity against Candida was limited. Stingless bee honey samples varied in activity and the basis for this remains to be determined. SIGNIFICANCE AND IMPACT OF THE STUDY: Stingless bee honey had similar activity to medicinal honey and may therefore have a role as a medicinal agent.


Asunto(s)
Antiinfecciosos/farmacología , Abejas/química , Miel , Animales , Candida albicans/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana
18.
Arch Virol ; 152(2): 305-20, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17066250

RESUMEN

An activator protein, Alt, synthesized during the early state of lytic infection is required for transcription of the late operon in the lactococcal phage TP901-1. In order to identify amino acid residues in the Alt protein required for activation of the TP901-1 late promoter, P(late), hydroxylamine mutagenesis was performed, resulting in almost saturating mutagenesis of alt. Twenty-three different non-functional alt alleles containing one, and in one case two amino acid exchanges were isolated and analyzed. Eight of the twenty-three mutant proteins were still able to activate the P(late) promoter to some extent. Our results show that alt encodes a protein of 16.7 kDa and that the last fourteen amino acids in the C-terminal part of the protein are required for activation of the P(late) promoter. By combining sequence analysis with experimental data we suggest that the C-terminal half of the Alt protein contains a helix-turn-helix-like motif involved in DNA binding. We also propose that the C-terminal half of the Alt protein may be involved in interactions with the bacterial RNA polymerase, whereas the N-terminal half of the protein is proposed to be important for the overall protein structure.


Asunto(s)
Análisis Mutacional de ADN , Lactococcus lactis/virología , Transcripción Genética , Activación Transcripcional , Proteínas Virales/química , Alelos , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Genes Virales , Secuencias Hélice-Giro-Hélice , Lactococcus lactis/genética , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Proteínas Virales/genética , Proteínas Virales/metabolismo
19.
Clin Microbiol Rev ; 19(1): 50-62, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16418522

RESUMEN

Complementary and alternative medicines such as tea tree (melaleuca) oil have become increasingly popular in recent decades. This essential oil has been used for almost 100 years in Australia but is now available worldwide both as neat oil and as an active component in an array of products. The primary uses of tea tree oil have historically capitalized on the antiseptic and anti-inflammatory actions of the oil. This review summarizes recent developments in our understanding of the antimicrobial and anti-inflammatory activities of the oil and its components, as well as clinical efficacy. Specific mechanisms of antimicrobial and anti-inflammatory action are reviewed, and the toxicity of the oil is briefly discussed.


Asunto(s)
Melaleuca/química , Enfermedades Cutáneas Infecciosas/tratamiento farmacológico , Aceite de Árbol de Té , Bacterias/efectos de los fármacos , Hongos/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , Enfermedades Cutáneas Infecciosas/etiología , Aceite de Árbol de Té/efectos adversos , Aceite de Árbol de Té/farmacología , Aceite de Árbol de Té/uso terapéutico
20.
Food Chem Toxicol ; 44(5): 616-25, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16243420

RESUMEN

The essential oil of Melaleuca alternifolia, also known as tea tree or melaleuca oil, is widely available and has been investigated as an alternative antimicrobial, anti-inflammatory and anti-cancer agent. While these properties are increasingly well characterised, relatively limited data are available on the safety and toxicity of the oil. Anecdotal evidence from almost 80 years of use suggests that the topical use of the oil is relatively safe, and that adverse events are minor, self-limiting and occasional. Published data indicate that TTO is toxic if ingested in higher doses and can also cause skin irritation at higher concentrations. Allergic reactions to TTO occur in predisposed individuals and may be due to the various oxidation products that are formed by exposure of the oil to light and/or air. Adverse reactions may be minimised by avoiding ingestion, applying only diluted oil topically and using oil that has been stored correctly. Data from individual components suggest that TTO has the potential to be developmentally toxic if ingested at higher doses, however, TTO and its components are not genotoxic. The limited ecotoxicity data available indicate that TTO is toxic to some insect species but more studies are required.


Asunto(s)
Dermatitis Alérgica por Contacto/etiología , Aceite de Árbol de Té/efectos adversos , Aceite de Árbol de Té/toxicidad , Administración Oral , Administración Tópica , Animales , Antiinfecciosos Locales/efectos adversos , Antiinfecciosos Locales/uso terapéutico , Antiinfecciosos Locales/toxicidad , Antiinflamatorios/efectos adversos , Antiinflamatorios/uso terapéutico , Antiinflamatorios/toxicidad , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Antineoplásicos/toxicidad , Bioensayo , Línea Celular , Dermatitis Alérgica por Contacto/inmunología , Humanos , Aceite de Árbol de Té/química , Aceite de Árbol de Té/uso terapéutico
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