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1.
Lasers Surg Med ; 55(8): 741-747, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37293831

RESUMEN

OBJECTIVE: Port wine birthmarks (PWBs) are vascular malformations affecting 0.3%-0.5% of newborns with the tendency to persist into adulthood without adequate treatment of the heterogenous ectatic vessels. This study compares treatment outcomes and parameters of the prior generation pulsed dye laser (PPDL) and the larger spot novel generation pulsed dye laser (NPDL) to establish whether a larger spot size laser provides greater clearance with fewer treatments. METHODS: One hundred and sixty patients were treated with either the PPDL (80 patients) and NPDL (80 patients) with retrospective review of age, body site, laser treatment parameters, number of treatments, and improvement following laser therapy. RESULTS: Patients treated with PPDL were older on average than patients treated with NPDL (mean 24.8 ± 19.7 vs. mean 17.1± 19.3 years, p < 0.05). The majority of lesions treated with PPDL were located on the face and neck, whereas truncal and extremity sites were more frequently treated with the NPDL. Use of NPDL was associated with a mean maximum spot size of 13.1 mm and mean maximum fluence of 7.3 J/cm2 with pulse durations of 0.45-3 ms, whereas use of the PPDL was associated with a mean spot size of 10.8 mm and mean maximum fluence of 8.8 J/cm2 with pulse durations of 0.45-6 ms. Fifty percent improvement was seen with 8.8 PPDL treatments compared to 4.3 NPDL treatments (p ≤ 0.01) with no significant difference in overall mean improvement between both devices at the chosen parameters. Multiple regression analysis showed that device type, not age or lesion location, was the only statistically significant independent variable to affect the endpoint of at least 50% improvement of the lesion. CONCLUSIONS: Use of the larger spot NPDL is associated with achieving 50% improvement with fewer treatments.


Asunto(s)
Terapia por Láser , Láseres de Colorantes , Terapia por Luz de Baja Intensidad , Mancha Vino de Oporto , Recién Nacido , Humanos , Niño , Adulto , Láseres de Colorantes/uso terapéutico , Resultado del Tratamiento , Mancha Vino de Oporto/radioterapia , Mancha Vino de Oporto/cirugía , Mancha Vino de Oporto/patología
2.
Sci Total Environ ; 882: 163550, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37080318

RESUMEN

Conversion of natural land cover can degrade water quality in water supply watersheds and increase treatment costs for Public Water Systems (PWSs), but there are few studies that have fully evaluated land cover and water quality relationships in mixed use watersheds across broad hydroclimatic settings. We related upstream land cover (forest, other natural land covers, development, and agriculture) to observed and modeled water quality across the southeastern US and specifically at 1746 PWS drinking water intake facilities. While there was considerable complexity and variability in the relationship between land cover and water quality, results suggest that Total Nitrogen (TN), Total Phosphorus (TP) and Suspended Sediment (SS) concentrations decrease significantly with increasing forest cover, and increase with increasing developed or agricultural cover. Catchments with dominant (>90 %) agricultural land cover had the greatest export rates for TN, TP, and SS based on SPARROW model estimates, followed by developed-dominant, then forest- and other-natural-dominant catchments. Variability in modeled TN, TP, and SS export rates by land cover type was driven by variability in natural background sources and catchment characteristics that affected water quality even in forest-dominated catchments. Both intake setting (i.e., run-of-river or reservoir) and upstream land cover were important determinants of water quality at PWS intakes. Of all PWS intakes, 15 % had high raw water quality, and 85 % of those were on reservoirs. Of the run-of-river intakes with high raw water quality, 75 % had at least 50 % forest land cover upstream. In addition, PWS intakes obtaining surface water supply from smaller upstream catchments may experience the largest losses of natural land cover based on projections of land cover in 2070. These results illustrate the complexity and variability in the relationship between land cover and water quality at broad scales, but also suggest that forest conservation can enhance the resilience of drinking water supplies.


Asunto(s)
Agua Potable , Calidad del Agua , Ecosistema , Monitoreo del Ambiente , Bosques , Agricultura , Fósforo , Ríos , Nitrógeno/análisis
3.
J Diet Suppl ; 20(5): 763-776, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36017806

RESUMEN

In this study, hydroethanolic extracts of 30 top-selling botanicals (herbs) commonly used as ingredients of herbal dietary supplements in the US were screened for their potential to activate the human pregnane X receptor (hPXR) and human aryl hydrocarbon receptor (hAhR) and to increase the activities of hPXR- and hAhR-regulated drug metabolizing cytochrome P450 enzymes (i.e., CYP3A4 and CYP1A2, respectively). Of the 30 botanicals tested, 21 induced PXR and 29 induced AhR transcriptional activities. Out of the 21 botanicals that induced hPXR transcriptional activity, 14 yielded >50% induction in CYP3A4 activity at concentrations ranging from 6 to 60 µg/mL and 16 out of the 29 botanicals that activated hAhR yielded >50% induction in CYP1A2 activity at concentrations ranging from 3 to 30 µg/mL. Moreover, eight botanicals (G. gummi-gutta [garcinia], Hemp [low and high CBD content], H. perforatum [St. John's wort], M. vulgare [horehound], M. oleifera [moringa], O. vulgare [oregano], P. johimbe [yohimbe] and W. somnifera [ashwagandha]) yielded >50% induction in both CYP3A4 and CYP1A2 activity. Herbal products are mixtures of phytoconstituents, any of which could modulate drug metabolism. Our data reveals that several top-selling botanicals may pose herb-drug interaction (HDI) risks via CYP450 induction. While in vitro experiments can provide useful guidance in assessing a botanical's HDI potential, their clinical relevance needs to be investigated in vivo. Botanicals whose effects on hPXR/CYP3A4, and hAhR/CYP1A2 activity were most pronounced will be slated for further clinical investigation.


Asunto(s)
Citocromo P-450 CYP1A2 , Receptores de Esteroides , Humanos , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP3A/metabolismo , Receptores de Esteroides/metabolismo , Interacciones de Hierba-Droga , Receptores de Hidrocarburo de Aril/metabolismo
4.
J Ethnopharmacol ; 301: 115822, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36223846

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The last three decades have witnessed a surge in popularity and consumption of herbal products. An unintended consequence of such popularity is that chronic consumption of these products can often modulate the functions of various proteins involved in drug disposition and may, in turn, impose risks for herb-drug interactions (HDIs), leading to serious adverse health outcomes. Identifying plants that may give rise to clinically relevant HDIs is essential, and proactive dissemination of such research outcomes is necessary for researchers, clinicians, and average consumers. AIM OF THE STUDY: The main objective of this study was to evaluate the HDI potential of plants commonly used as ingredients in many herbal products, including BDS. MATERIALS AND METHODS: The dried material of 123 plants selected from the NCNPR repository was extracted with 95% ethanol. The extracts were screened for agonistic effects on nuclear receptors (PXR and AhR) by reporter gene assays in PXR-transfected HepG2 and AhR-reporter cells. For cytochrome P450 enzyme (CYP) inhibition studies, CYP450 baculosomes were incubated with enzyme-specific probe substrates by varying concentrations of extracts. The inhibitory effect on the efflux transporter P-glycoprotein (P-gp) was investigated via rhodamine (Rh-123) uptake assay in P-gp overexpressing MDR1-MDCK cells. RESULTS: Out of 123 plants, 16 increased transcriptional activity of human PXR up to 4 to 7-fold at 60 µg/mL, while 18 plants were able to increase AhR activity up to 10 to 40-fold at 30 µg/mL. Thirteen plants inhibited the activity of CYP3A4, while 10 plants inhibited CYP1A2 activity with IC50 values in the range of 1.3-10 µg/mL. Eighteen plants (at 50 µg/mL) increased intracellular accumulation of Rh-123 (>150%) in MDR1-MDCK cells. Additionally, other plants tested in this study were able to activate PXR, AhR, or both to lesser extents, and several inhibited the catalytic activity of CYPs at higher concentrations (IC50 >10 µg/mL). CONCLUSIONS: The results indicate that prolonged or excessive consumption of herbal preparations rich in such plants (presented in Figs. 1a, 2a, 3a, 4a, and 5a) may pose a risk for CYP- and P-gp-mediated HDIs, leading to unwanted side effects due to the altered pharmacokinetics of concomitantly ingested medications.


Asunto(s)
Plantas Medicinales , Receptores de Esteroides , Humanos , Interacciones de Hierba-Droga , Plantas Medicinales/metabolismo , Receptor X de Pregnano , Receptores de Esteroides/genética , Extractos Vegetales/farmacología , Sistema Enzimático del Citocromo P-450/metabolismo , Citocromo P-450 CYP3A/metabolismo , Receptores Citoplasmáticos y Nucleares
5.
Pediatr Infect Dis J ; 39(12): 1092-1100, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32773662

RESUMEN

BACKGROUND: Ceftazidime-avibactam is an effective agent for the treatment of tuberculosis (TB) but requires frequent administration because of a short half-life. Due to a longer half-life, ceftriaxone could allow intermittent dosing. METHODS: First, we identified the MIC of ceftriaxone with 15 mg/L avibactam in 30 clinical Mycobacterium tuberculosis isolates. Next, 2 ceftriaxone exposure-effect studies in the intracellular hollow fiber model of TB (HFS-TB) that mimics disseminated disease in young children, were performed. Ceftriaxone was administered once or twice daily for 28 days to explore percentage of time that the concentration persisted above MIC (%TMIC) ranging from 0 to 100%. In a third HFS-TB experiment, the "double cephalosporin" regimen of ceftazidime-ceftriaxone-avibactam was examined and analyzed using Bliss Independence. CONCLUSION: The MIC99 of the clinical strains was 32 mg/L, in the presence of 15 mg/L avibactam. Ceftriaxone %TMIC <42 had no microbial effect in the HFS-TB, %TMIC >54% demonstrated a 4.1 log10 colony-forming units per milliliter M. tuberculosis kill, while %TMIC mediating Emax was 68%. The "double cephalosporin" combination was highly synergistic. Monte Carlo experiments of 10,000 subjects identified the optimal ceftriaxone dose as 100 mg/kg twice a day. CONCLUSION: The combination of ceftriaxone-avibactam at 100 mg/kg could achieve Emax in >90% of children. The ceftriaxone potent activity M. tuberculosis could potentially shorten therapy in children with disseminated TB.


Asunto(s)
Antituberculosos , Compuestos de Azabiciclo , Ceftriaxona , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis Meníngea/microbiología , Antituberculosos/farmacocinética , Antituberculosos/farmacología , Compuestos de Azabiciclo/farmacocinética , Compuestos de Azabiciclo/farmacología , Ceftriaxona/farmacocinética , Ceftriaxona/farmacología , Humanos , Lactante , Recién Nacido , Pruebas de Sensibilidad Microbiana , Modelos Biológicos
6.
J Antimicrob Chemother ; 75(2): 392-399, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31713607

RESUMEN

OBJECTIVES: Animal models have suggested that the combination of pretomanid with pyrazinamide and moxifloxacin (PaMZ) may shorten TB therapy duration to 3-4 months. Here, we tested that in the hollow-fibre system model of TB (HFS-TB). METHODS: A series of HFS-TB experiments were performed to compare the kill rates of the PaMZ regimen with the standard three-drug combination therapy. HFS-TB experiments were performed with bacilli in log-phase growth treated for 28 days, intracellular bacilli treated daily for 28 days and semi-dormant Mycobacterium tuberculosis treated with daily therapy for 56 days for sterilizing effect. Next, time-to-extinction equations were employed, followed by morphism transformation and Latin hypercube sampling, to determine the proportion of patients who achieved a time to extinction of 3, 4 or 6 months with each regimen. RESULTS: Using linear regression, the HFS-TB sterilizing effect rates of the PaMZ regimen versus the standard-therapy regimen during the 56 days were 0.18 (95% credible interval=0.13-0.23) versus 0.15 (95% credible interval=0.08-0.21) log10 cfu/mL/day, compared with 0.16 (95% credible interval=0.13-0.18) versus 0.11 (95% credible interval=0.09-0.13) log10 cfu/mL/day in the Phase II clinical trial, respectively. Using time-to-extinction and Latin hypercube sampling modelling, the expected percentages of patients in which the PaMZ regimen would achieve sterilization were 40.37% (95% credible interval=39.1-41.34) and 72.30% (95% credible interval=71.41-73.17) at 3 and 4 months duration of therapy, respectively, versus 93.67% (95% credible interval=93.18-94.13) at 6 months for standard therapy. CONCLUSIONS: The kill rates of the PaMZ regimen were predicted to be insufficient to achieve cure in less than 6 months in most patients.


Asunto(s)
Moxifloxacino/uso terapéutico , Mycobacterium tuberculosis/efectos de los fármacos , Nitroimidazoles/uso terapéutico , Pirazinamida/uso terapéutico , Tuberculosis/tratamiento farmacológico , Antituberculosos/uso terapéutico , Quimioterapia Combinada , Humanos , Matemática
7.
J Antimicrob Chemother ; 74(6): 1607-1617, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30820554

RESUMEN

BACKGROUND: MDR-TB and XDR-TB have poor outcomes. OBJECTIVES: To examine the efficacy of tigecycline monotherapy in the hollow fibre system model of TB. METHODS: We performed pharmacokinetic/pharmacodynamic studies using tigecycline human-like concentration-time profiles in the hollow fibre system model of TB in five separate experiments using Mycobacterium tuberculosis in log-phase growth or as semi-dormant or intracellular bacilli, as monotherapy. We also compared efficacy with the isoniazid/rifampicin/pyrazinamide combination (standard therapy). We then applied extinction mathematics, morphisms and Latin hypercube sampling to identify duration of therapy with tigecycline monotherapy. RESULTS: The median tigecycline MIC for 30 M. tuberculosis clinical and laboratory isolates (67% MDR/XDR) was 2 mg/L. Tigecycline monotherapy was highly effective in killing M. tuberculosis in log-phase-growth and semi-dormant and intracellular M. tuberculosis. Once-a-week dosing had the same efficacy as daily therapy for the same cumulative dose; thus, tigecycline efficacy was linked to the AUC0-24/MIC ratio. Tigecycline replacement by daily minocycline after 4 weeks of therapy was effective in sterilizing bacilli. The AUC0-24/MIC ratio associated with optimal kill was 42.3. Tigecycline monotherapy had a maximum sterilizing effect (day 0 minus day 28) of 3.06 ±âŸ0.20 log10 cfu/mL (r2 = 0.92) compared with 3.92 ±âŸ0.45 log10 cfu/mL (r2 = 0.80) with optimized standard therapy. In our modelling, at a tigecycline monotherapy duration of 12 months, the proportion of patients with XDR-TB who reached bacterial population extinction was 64.51%. CONCLUSIONS: Tigecycline could cure patients with XDR-TB or MDR-TB who have failed recommended therapy. Once-a-week tigecycline could also replace second-line injectables in MDR-TB regimens.


Asunto(s)
Antituberculosos/administración & dosificación , Mycobacterium tuberculosis/efectos de los fármacos , Tigeciclina/administración & dosificación , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Antituberculosos/farmacocinética , Esquema de Medicación , Monitoreo de Drogas , Quimioterapia Combinada , Humanos , Pruebas de Sensibilidad Microbiana , Modelos Teóricos , Método de Montecarlo , Tigeciclina/farmacocinética , Distribución Tisular
8.
Clin Infect Dis ; 67(suppl_3): S342-S348, 2018 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-30496456

RESUMEN

Background: Children are often neglected during early development of antituberculosis agents, and most receive treatment after it is first tested in adults. However, very young children have tuberculosis that differs in many respects from adult cavitary pneumonia and could have different toxicity profiles to drugs. Linezolid is effective against intracellular tuberculosis, a common manifestation in young children. However, linezolid has considerable toxicity due to inhibition of mitochondrial enzymes. Tedizolid could be a replacement if it shows equal efficacy and reduced toxicity. Methods: We performed tedizolid dose-effect studies in the hollow fiber system model of intracellular tuberculosis. We measured linezolid concentrations, colony-forming units (CFU), time-to-positivity, and monocyte viability and performed RNA sequencing on infected cells collected from repetitive sampling of each system. We also compared efficacy of tedizolid vs linezolid and vs tedizolid-moxifloxacin combination. Results: There was no downregulation of mitochondrial enzyme genes, with a tedizolid 0-24 hour area under the concentration-time curve (AUC0-24) of up to 90 mg*h/L. Instead, high exposures led to increased mitochondrial gene expression and monocyte survival. The AUC0-24 to minimum inhibitory concentration ratio associated with 80% of maximal bacterial kill (EC80) was 184 by CFU/mL (r2 = 0.96) and 189 by time-to-positivity (r2 = 0.99). Tedizolid EC80 killed 4.0 log10 CFU/mL higher than linezolid EC80. The tedizolid-moxifloxacin combination had a bacterial burden elimination rate constant of 0.27 ± 0.05 per day. Conclusions: Tedizolid demonstrated better efficacy than linezolid, without the mitochondrial toxicity gene or cytotoxicity signatures encountered with linezolid. Tedizolid-moxifloxacin combination had a high bacterial elimination rate.


Asunto(s)
Antibacterianos/farmacocinética , Moxifloxacino/farmacocinética , Mycobacterium tuberculosis/efectos de los fármacos , Oxazolidinonas/farmacocinética , Tetrazoles/farmacocinética , Tuberculosis/tratamiento farmacológico , Antibacterianos/uso terapéutico , Niño , Relación Dosis-Respuesta a Droga , Humanos , Pruebas de Sensibilidad Microbiana , Moxifloxacino/uso terapéutico , Oxazolidinonas/uso terapéutico , Tetrazoles/uso terapéutico , Tuberculosis/microbiología
9.
Artículo en Inglés | MEDLINE | ID: mdl-29180526

RESUMEN

The modern chemotherapy era started with Fleming's discovery of benzylpenicillin. He demonstrated that benzylpenicillin did not kill Mycobacterium tuberculosis In this study, we found that >64 mg/liter of static benzylpenicillin concentrations killed 1.16 to 1.43 log10 CFU/ml below starting inoculum of extracellular and intracellular M. tuberculosis over 7 days. When we added the ß-lactamase inhibitor avibactam, benzylpenicillin maximal kill (Emax) of extracellular log-phase-growth M. tuberculosis was 6.80 ± 0.45 log10 CFU/ml at a 50% effective concentration (EC50) of 15.11 ± 2.31 mg/liter, while for intracellular M. tuberculosis it was 2.42 ± 0.14 log10 CFU/ml at an EC50 of 6.70 ± 0.56 mg/liter. The median penicillin (plus avibactam) MIC against South African clinical M. tuberculosis strains (80% either multidrug or extensively drug resistant) was 2 mg/liter. We mimicked human-like benzylpenicillin and avibactam concentration-time profiles in the hollow-fiber model of tuberculosis (HFS-TB). The percent time above the MIC was linked to effect, with an optimal exposure of ≥65%. At optimal exposure in the HFS-TB, the bactericidal activity in log-phase-growth M. tuberculosis was 1.44 log10 CFU/ml/day, while 3.28 log10 CFU/ml of intracellular M. tuberculosis was killed over 3 weeks. In an 8-week HFS-TB study of nonreplicating persistent M. tuberculosis, penicillin-avibactam alone and the drug combination of isoniazid, rifampin, and pyrazinamide both killed >7.0 log10 CFU/ml. Monte Carlo simulations of 10,000 preterm infants with disseminated disease identified an optimal dose of 10,000 U/kg (of body weight)/h, while for pregnant women or nonpregnant adults with pulmonary tuberculosis the optimal dose was 25,000 U/kg/h, by continuous intravenous infusion. Penicillin-avibactam should be examined for effect in pregnant women and infants with drug-resistant tuberculosis, to replace injectable ototoxic and teratogenic second-line drugs.


Asunto(s)
Antituberculosos/uso terapéutico , Mycobacterium tuberculosis/efectos de los fármacos , Penicilina G/uso terapéutico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Adulto , Compuestos de Azabiciclo/uso terapéutico , Línea Celular , Combinación de Medicamentos , Femenino , Humanos , Isoniazida/uso terapéutico , Pruebas de Sensibilidad Microbiana/métodos , Método de Montecarlo , Embarazo , Pirazinamida/uso terapéutico , Rifampin/uso terapéutico
10.
Mo Med ; 108(1): 60-3, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21462614

RESUMEN

Cosmeceuticals represent a new category of products placed between cosmetics and pharmaceuticals that are intended for the enhancement of both the health and beauty of skin. Encompassing an ever-increasing part of the skin care industry, cosmeceuticals are formulated from a multitude of ingredients, the main categories of which are discussed in this article. Given the growing interest in these products among patients and the strong claims made by manufacturers, it is important that physicians recognize these agents and understand their benefits, limitations, and potential adverse effects.


Asunto(s)
Cosméticos/uso terapéutico , Envejecimiento de la Piel/efectos de los fármacos , Cuidados de la Piel/métodos , Enfermedades de la Piel/prevención & control , Vitaminas/uso terapéutico , Belleza , Humanos , Péptidos y Proteínas de Señalización Intercelular/uso terapéutico , Fitoterapia/métodos
11.
Plant Cell Environ ; 33(3): 344-57, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19906150

RESUMEN

Effects of salinity and nutrients on carbon gain in relation to water use were studied in the grey mangrove, Avicennia marina, growing along a natural salinity gradient in south-eastern Australia. Tall trees characterized areas of seawater salinities (fringe zone) and stunted trees dominated landward hypersaline areas (scrub zone). Trees were fertilized with nitrogen (+N) or phosphorus (+P) or unfertilized. There was no significant effect of +P on shoot growth, whereas +N enhanced canopy development, particularly in scrub trees. Scrub trees maintained greater CO(2) assimilation per unit water transpired (water-use efficiency, WUE) and had lower nitrogen-use efficiency (NUE; CO(2) assimilation rate per unit leaf nitrogen) than fringe trees. The CO(2) assimilation rates of +N trees were similar to those in other treatments, but were achieved at lower transpiration rates, stomatal conductance and intercellular CO(2) concentrations. Maintaining comparable assimilation rates at lower stomatal conductance requires greater ribulose 1.5-bisphosphate carboxylase/oxygenase activity, consistent with greater N content per unit leaf area in +N trees. Hence, +N enhanced WUE at the expense of NUE. Instantaneous WUE estimates were supported by less negative foliar delta(13)C values for +N trees and scrub control trees. Thus, nutrient enrichment may alter the structure and function of mangrove forests along salinity gradients.


Asunto(s)
Avicennia/fisiología , Fertilizantes , Nitrógeno/metabolismo , Salinidad , Avicennia/crecimiento & desarrollo , Dióxido de Carbono/metabolismo , Fósforo/metabolismo , Fotosíntesis , Brotes de la Planta/crecimiento & desarrollo , Estomas de Plantas/fisiología , Transpiración de Plantas , Australia del Sur , Agua/metabolismo
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