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1.
Theriogenology ; 221: 1-8, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38518659

RESUMEN

The aim of the study was to determine the effect of carbetocin administration (a long-acting analog of oxytocin) 20 or 10 min before electroejaculation (EE) on the duration of semen collection procedure, quantitative and qualitative characteristics of the ejaculate, and stress biomarkers in rams. Semen was collected from 12 Corriedale rams (age, 2.5-5.5 years old) with EE, in a Latin-square design, administrating carbetocin (0.2 mg/100 kg of body weight i.v.) 20 or 10 min before EE, or without carbetocin administration (CB-20, CB-10, and CON treatments, respectively). Each treatment was applied to different rams every 3-4 days, allowing all the rams to receive all three treatments. Carbetocin administered 20 or 10 min before EE increased the number of sperm ejaculated (P = 0.01), the semen concentration (P = 0.02), the number of insemination doses collected in a single collection (P = 0.01), and the number of insemination doses collected/electrical pulses administered (P = 0.05) compared to control rams. Carbetocin administered 20 or 10 min before semen collection prolonged the time required for EE and the number of pulses administered during EE compared to CON rams (P < 0.03 for both). The CB-10 rams required the administration of more electrical pulses during ejaculation than CON rams (P = 0.001), and CB-20 treatment tended to require more electrical pulses than CON rams (P = 0.06). The volume of the ejaculate was greater in CB-10 than in CON rams (P = 0.01), and that of CB-20 treatment tended to be greater than CON rams (P = 0.08). The percentage of sperm with intact membrane was greater in CB-20 than in CON rams (P = 0.01). Total protein, albumin, and globulin concentrations were lower immediately after carbetocin administration 20 or 10 min before EE. The treatments did not affect cortisol concentration, glycemia, rectal and surface temperatures, heart rate, and facial expressions. Carbetocin administration before EE of rams improved the quantitative and qualitative characteristics of the ejaculate, duplicating the number of insemination doses collected. It can be a promising treatment to obtain a greater quantity of doses to inseminate with a lower frequency of semen collections, reducing the negative impacts of EE on animal welfare.


Asunto(s)
Oxitocina , Oxitocina/análogos & derivados , Semen , Masculino , Ovinos , Animales , Semen/fisiología , Oxitocina/farmacología , Oveja Doméstica , Espermatozoides/fisiología , Eyaculación/fisiología , Inseminación
2.
J Eur Acad Dermatol Venereol ; 33 Suppl 7: 25-33, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31588614

RESUMEN

Octocrylene or octocrilene is an organic ultraviolet (UV) filter which absorbs mainly UVB radiation and short UVA wavelengths. It is used in various cosmetic products to either provide an appropriate sun protection factor in sunscreen products or to protect cosmetic formulations from UV radiation. There is no discussion that UV filters are beneficial ingredients in cosmetics since they protect from skin cancer, but octocrylene has been recently incriminated to potentially induce adverse effects on the endocrine system in addition to having allergic and/or photoallergic potential. However, the substance has the advantage to work synergistically with other filters allowing a beneficial broad photoprotection, e.g. it stabilizes the UVA filter avobenzone (i.e. butylmethoxydibenzoylmethane). Like all chemicals used in cosmetics, the safety profile of octocrylene is constantly under assessment by the European Chemical Agency (ECHA) since it has been registered according to the European regulation Registration, Evaluation, Authorisation and Restriction of Chemicals. Summaries of safety data of octocrylene are publicly available on the ECHA website. This review aims to present the main safety data from the ECHA website, as well as those reported in scientific articles from peer-reviewed journals. The available data show that octocrylene does not have any endocrine disruption potential. It is a rare sensitizer, photocontact allergy is more frequent and it is considered consecutive to photosensitization to ketoprofen. Based on these results, octocrylene can be considered as safe when used as a UV filter in cosmetic products at a concentration up to 10%.


Asunto(s)
Acrilatos/efectos adversos , Cosméticos/efectos adversos , Dermatitis Alérgica por Contacto/etiología , Protectores Solares/efectos adversos , Acrilatos/farmacocinética , Acrilatos/toxicidad , Administración Cutánea , Administración Oral , Animales , Disponibilidad Biológica , Cosméticos/química , Disruptores Endocrinos/efectos adversos , Humanos , Reproducción/efectos de los fármacos , Absorción Cutánea , Protectores Solares/farmacocinética , Protectores Solares/toxicidad , Rayos Ultravioleta
3.
J Eur Acad Dermatol Venereol ; 33(8): 1496-1505, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30897234

RESUMEN

Indoor and outdoor airborne pollutants modify our environment and represent a growing threat to human health worldwide. Airborne pollution effects on respiratory and cardiac health and diseases have been well established, but its impact on skin remains poorly described. Nonetheless, the skin is one of the main targets of pollutants, which reach the superficial and deeper skin layers by transcutaneous and systemic routes. In this review, we report the outcomes of basic and clinical research studies monitoring pollutant levels in human tissues including the skin and hair. We present a current understanding of the biochemical and biophysical effects of pollutants on skin metabolism, inflammatory processes and oxidative stress, with a focus on polyaromatic hydrocarbons and ground-level ozone that are widespread outdoor pollutants whose effects are mostly studied. We reviewed the literature to report the clinical effects of pollutants on skin health and skin ageing and their impact on some chronic inflammatory skin diseases. We also discuss the potential interactions of airborne pollutants with either ultraviolet radiation or human skin microbiota and their specific impact on skin health.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Piel/efectos de los fármacos , Contaminantes Atmosféricos/análisis , Humanos , Microbiota , Estrés Oxidativo , Piel/química , Piel/microbiología , Envejecimiento de la Piel/efectos de los fármacos , Rayos Ultravioleta
4.
J Eur Acad Dermatol Venereol ; 32(5): 812-819, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29377341

RESUMEN

BACKGROUND: Acne vulgaris is one of the main reasons for dermatological consultations. Severity and response to treatment may be impacted by various external factors or exposome. AIM: To assess the impact of environmental factors on acne and to provide a comprehensive overview of the acne exposome. METHODS: Two consensus meetings of five European dermatologists and a comprehensive literature search on exposome factors triggering acne served as a basis for this review. RESULTS: Acne exposome was defined as the sum of all environmental factors influencing the occurrence, duration and severity of acne. Exposome factors impact on the response and the frequency of relapse to treatments by interacting with the skin barrier, sebaceous gland, innate immunity and cutaneous microbiota. They may be classified into the following six main categories: nutrition, psychological and lifestyle factors, occupational factors including cosmetics, as well as pollutants, medication and climatic factors. Moreover, practical considerations for the dermatologist's clinical practice are proposed. CONCLUSION: Exposome factors including nutrition, medication, occupational factors, pollutants, climatic factors, and psychosocial and lifestyle factors may impact on the course and severity of acne and on treatment efficacy. Identifying and reducing the impact of exposome is important for an adequate acne disease management.


Asunto(s)
Acné Vulgar , Contaminantes Atmosféricos/efectos adversos , Dieta , Acné Vulgar/etiología , Clima , Consenso , Cosméticos/efectos adversos , Dieta/efectos adversos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Hormonas/efectos adversos , Humanos , Estilo de Vida , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
5.
J Eur Acad Dermatol Venereol ; 30(12): 2038-2047, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27735094

RESUMEN

The skin is a complex barrier organ made of a symbiotic relationship between microbial communities and host tissue via complex signals provided by the innate and the adaptive immune systems. It is constantly exposed to various endogenous and exogenous factors which impact this balanced system potentially leading to inflammatory skin conditions comprising infections, allergies or autoimmune diseases. Unlike the gut and stool microbiome which has been studied and described for many years, investigations on the skin or scalp microbiome only started recently. Researchers in microbiology and dermatology started using modern methods such as pyrosequencing assays of bacterial 16S rRNA genes to identify and characterize the different microorganisms present on the skin, to evaluate the bacterial diversity and their relative abundance and to understand how microbial diversity may contribute to skin health and dermatological conditions. This article aims to provide an overview on the knowledge about the skin microbiota, the microbiome and their importance in dermatology.


Asunto(s)
Dermatólogos , Microbiota , Piel/microbiología , Bacterias/genética , Humanos , ARN Ribosómico 16S/genética
6.
Br J Dermatol ; 172 Suppl 1: 47-51, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25597636

RESUMEN

Inflammatory lesions commonly associated with acne have a propensity to form scars which can substantially impact an individual's quality of life. As a result of variations in collagen levels during the wound-healing process, different types of scars can form requiring a tailored approach to treatment; treatment success depends on the modality of the treatment chosen. Here, I briefly discuss the different acne scar types, and their relationship with skin anatomy and histology, in relation to the different treatment options available. This paper was developed to accompany my state of the art presentation at 'The Changing Faces of Acne' meeting in June 2014 and I aim to share my personal experiences in order to offer guidance for appropriate treatment decisions.


Asunto(s)
Acné Vulgar/terapia , Cicatriz/terapia , Trasplante de Médula Ósea/métodos , Ablación por Catéter/métodos , Dermabrasión/instrumentación , Dermabrasión/métodos , Rellenos Dérmicos/uso terapéutico , Humanos , Queratolíticos/uso terapéutico , Terapia por Láser/métodos , Agujas , Fototerapia/métodos , Calidad de Vida , Trasplante de Células Madre/métodos , Trasplante Autólogo
7.
J Eur Acad Dermatol Venereol ; 28(11): 1409-17, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24684296

RESUMEN

Our increased knowledge of normal skin physiology has ushered in a subtle revolution in cosmetic science. Originally designed as preparations to enhance personal appearance by direct application on to the skin, cosmetics have now taken on a new role in dermatology, through the support of the management of many skin disorders. This evolving role of cosmetics in skin care is primarily due to scientific and technological advancements that have changed our understanding of normal skin physiology and how cosmetics modify its appearance both physically and biologically. The vast array of techniques currently available to investigate skin responsivity to multiple stimuli has brought about a new era in cosmetic and dermocosmetic development based on a robust understanding of skin physiology and its varied responses to commonly encountered environmental insults. Most cosmetic research is undertaken on reconstructed skin models crucial in dermatological research, given the strict ban imposed by the European Union on animal testing. In addition, the design and conduct of trials evaluating cosmetics now follow rules comparable to those used in the development and evaluation of pharmaceutical products. Cosmetic research should now aim to ensure all trials adhere to strictly reproducible and scientifically sound methodologies. The objective of this review is to provide an overview of the multidisciplinary scientific approach used in formulating dermocosmetics, and to examine the major advances in dermocosmetic development and assessment, the safety and regulatory guidelines governing their production and the exciting future outlook for these dermocosmetic processes following good practice rules.


Asunto(s)
Cosméticos , Dermatología/tendencias , Investigación/tendencias , Química Farmacéutica/tendencias , Cosméticos/efectos adversos , Cosméticos/farmacología , Humanos , Piel/efectos de los fármacos , Fenómenos Fisiológicos de la Piel/efectos de los fármacos
8.
J Environ Manage ; 129: 423-34, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23995510

RESUMEN

Zn(II) and Cd(II) removal by biosorption using Undaria pinnatifida was studied in batch and dynamic systems. The kinetic uptake follows a pseudo second order rate equation indicating that the rate limiting step is a chemical reaction. The equilibrium data are described by the Langmuir isotherm in mono-component solutions. In binary solutions, the Jain and Snowyink model shows that most of the active sites are exclusively accessible to cadmium ions without competition with the zinc ions. The dynamic studies show that the biosorbent has higher retention and affinity for Cd(II) than for Zn(II) in both mono- and bi-component systems. SEM-EDX analysis indicates that the active sites are heterogeneously distributed on the cell wall surface. FT-IR spectrometry characterization shows that carboxylic groups and chemical groups containing N and S contribute to Zn(II) and Cd(II) uptake by U. pinnatifida. According to these results calcium-treated U. pinnatifida is a suitable adsorbent for Zn(II) and Cd(II) pollutants.


Asunto(s)
Cadmio/metabolismo , Restauración y Remediación Ambiental/métodos , Undaria/metabolismo , Eliminación de Residuos Líquidos/métodos , Zinc/metabolismo , Adsorción , Argentina , Biodegradación Ambiental , Monitoreo del Ambiente , Cinética , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier
10.
Bioresour Technol ; 116: 195-203, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22609676

RESUMEN

Zinc and cadmium can be efficiently removed from solutions using the brown algae, Macrocystis pyrifera. Treatment with CaCl(2) allowed stabilization of the biosorbent. The maximum biosorption capacities in mono-component systems were 0.91 mmol g(-1) and 0.89 mmol g(-1) and the Langmuir affinity coefficients were 1.76 L mmol(-1) and 1.25 L mmol(-1) for Zn(II) and Cd(II), respectively. In two-component systems, Zn(II) and Cd(II) adsorption capacities were reduced by 50% and 40%, respectively and the biosorbent showed a preference for Cd(II) over Zn(II). HNO(3) (0.1M) and EDTA (0.1M) achieved 90-100% desorption of both ions from the loaded biomass. While HNO(3) preserved the biomass structure, EDTA destroyed it completely. Fourier transform infrared spectra identified the contribution of carboxylic, amine and sulfonate groups on Zn(II) and Cd(II) biosorption. These results showed that biosorption using M. pyrifera-treated biomass could be an affordable and simple process for cadmium and zinc removal from wastewaters.


Asunto(s)
Técnicas de Cultivo Celular por Lotes/métodos , Cadmio/aislamiento & purificación , Calcio/farmacología , Macrocystis/efectos de los fármacos , Macrocystis/metabolismo , Zinc/aislamiento & purificación , Adsorción/efectos de los fármacos , Biodegradación Ambiental/efectos de los fármacos , Biomasa , Cinética , Solventes , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
11.
Neurosci Lett ; 491(1): 18-22, 2011 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-21215291

RESUMEN

A spinal cord hemi-section with a homologous transplant of medullar tissue at the level of C5-C6 and preservation of the anterior spinal artery was used to evaluate the histological characteristics such as quantity and quality of axons, myelin index and blood vessels after quadriplegia recovery. Vascular changes after spinal injury results in severe endothelial damage, axonal edema, neuronal necrosis and demyelinization as well as cysts and infarction. Preservation of the anterior spinal artery has demonstrated clinical recuperation; therefore, in addition to the lesion we included a homologous transplant to visualize changes at a cellular level. Two groups of dogs (hemi-section and transplant) went through a traumatic spinal cord hemi-section of 50% at the level of C5-C6. The transplant group formed by animals which simultaneously had 4 mm of spinal cord removed and the equal amount substituted from a donor animal at the level of C5-C6 corresponding to the half right side; both preserving the anterior spinal artery. Histological evaluation of all groups took place at days 3 (acute) and 28 (chronic) post-operation. Changes of degeneration and axonal regeneration were found in the hemi-section and transplant groups at acute and chronic time, as well as same quadriplegia recovery at chronic time in the hemi-section and transplant groups which closely related to mechanisms which participate in regeneration and functional recuperation due to the preservation of the anterior spinal artery and presence of new blood vessels.


Asunto(s)
Regeneración Nerviosa/fisiología , Cuadriplejía/cirugía , Recuperación de la Función/fisiología , Traumatismos de la Médula Espinal/cirugía , Médula Espinal/trasplante , Animales , Modelos Animales de Enfermedad , Perros , Masculino , Cuadriplejía/fisiopatología , Médula Espinal/irrigación sanguínea , Médula Espinal/fisiopatología , Traumatismos de la Médula Espinal/fisiopatología , Trasplante de Tejidos/métodos
12.
J Eur Acad Dermatol Venereol ; 25(6): 695-704, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21029205

RESUMEN

BACKGROUND: Superficial chemical peels offer therapeutic results in a convenient, affordable treatment. Many clinicians use these peels in the treatment of acne and acne-prone oily skin. OBJECTIVES: This article examines the evidence base that supports the widespread use of superficial peels in this setting. METHODS: A search of the English language medical literature was performed to identify clinical trials that formally evaluated the use of chemical peeling in active acne. RESULTS: Search of the literature revealed very few clinical trials of peels in acne (N=13); a majority of these trials included small numbers of patients, were not controlled and were open label. The evidence that is available does support the use of chemical peels in acne as all trials had generally favourable results despite differences in assessments, treatment regimens and patient populations. Notably, no studies of chemical peels have used an acne medication as a comparator. As not every publication specified whether or not concomitant acne medications were allowed, it is hard to evaluate clearly how many of the studies evaluated the effect of peeling alone. This may be appropriate, however, given that few clinicians would use superficial chemical peels as the sole treatment for acne except in rare instances where a patient could not tolerate other treatment modalities. CONCLUSIONS: In the future, further study is needed to determine the best use of chemical peels in this indication.


Asunto(s)
Acné Vulgar/terapia , Quimioexfoliación , Glicolatos/uso terapéutico , Queratolíticos/uso terapéutico , Ácido Pirúvico/uso terapéutico , Ácido Salicílico/uso terapéutico , Medicina Basada en la Evidencia , Humanos
13.
Br J Haematol ; 150(2): 209-17, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20507310

RESUMEN

Pathogen reduction (PR) of platelet products increases costs and available clinical studies are equivocal with respect to clinical and haemostatic effectiveness. We conducted a multicentre, open-label, randomized, non-inferiority trial comparing the clinical effectiveness of buffy-coat derived leukoreduced platelet concentrates (PC) stored for up to 7 d in plasma with platelets stored in platelet additive solution III (PASIII) without and with treatment with amotosalen-HCl/ultraviolet-A (UVA) photochemical pathogen reduction (PR-PASIII). Primary endpoint of the study was 1-h corrected count increment (CCI). Secondary endpoints were 24-h CCI, bleeding, transfusion requirement of red cells and PC, platelet transfusion interval and adverse transfusion reactions. Compared to plasma-PC, in the intention to treat analysis of 278 evaluable patients the mean difference for the 1-h CCI of PR-PASIII-PC and PASIII-PC was -31% (P < 0.0001) and -9% (P = n.s.), respectively. Twenty-seven patients (32%) had bleeding events in the PR-PASIII arm, as compared to 19 (19%) in the plasma arm and 14 (15%) in the PASIII arm (P = 0.034). Despite the potential advantages of pathogen (and leucocyte) inactivation of amotosalen-HCl/UVA-treated platelet products, their clinical efficacy is inferior to platelets stored in plasma, warranting a critical reappraisal of employing this technique for clinical use.


Asunto(s)
Plaquetas/microbiología , Conservación de la Sangre/métodos , Procedimientos de Reducción del Leucocitos/métodos , Transfusión de Plaquetas/métodos , Trombocitopenia/terapia , Adulto , Anciano , Infecciones Bacterianas/prevención & control , Infecciones Bacterianas/transmisión , Femenino , Furocumarinas , Hemorragia/etiología , Humanos , Masculino , Persona de Mediana Edad , Plasma , Transfusión de Plaquetas/efectos adversos , Resultado del Tratamiento , Rayos Ultravioleta , Virosis/prevención & control , Virosis/transmisión
14.
J Eur Acad Dermatol Venereol ; 24(3): 281-92, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19744174

RESUMEN

BACKGROUND/OBJECTIVES: Peelings are among the oldest and most widespread aesthetic procedures used in aesthetic dermatology worldwide. More than 50 commercial peelings are currently available on the European market. MATERIALS AND METHODS: In the present review, we summarise the current knowledge on chemical peels. RESULTS/CONCLUSIONS: A state-of-the-art peeling procedure will take into account the depth of the targeted structure and the skin condition of the patient to choose carefully among the variables such as chemical class of the peeling agent, concentration, frequency and pressure of the application. The usual classification of chemical peels comprises superficial, medium and deep peels. For superficial peels alpha-hydroxy-acids and most recently lipo-hydroxy acid are used to induce an exfoliation of the epidermis. Medium-depth agents such as trichloroacetic acid (<50%) cause an epidermal to papillary dermal peel and regeneration. Deep peels using trichloroacetic acid (>50%) or phenol based formulations reach the reticular dermis to induce dermal regeneration. The success of any peel is crucially dependent on the physicians understanding of the chemical and biological processes, as well as of indications, clinical effectiveness and side effects of the procedures.


Asunto(s)
Quimioexfoliación/métodos , Dermatología/tendencias , Estética , Envejecimiento de la Piel/efectos de los fármacos , Enfermedades de la Piel/terapia , Dermatología/métodos , Humanos
15.
G Ital Dermatol Venereol ; 144(3): 243-57, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19528906

RESUMEN

Keloids and other scars are different manifestations of the normal wound healing process. If located in visible areas, scars may have a psychological impact that could affect the quality of life of the scar-bearing population. Good preoperatory planning including hiding incisions in natural anatomical landmarks or placing them parallel to relaxed skin tension lines are among the techniques used to improve the cosmesis of scars. Once a prominent or noticeable scar has developed, multiple therapeutic modalities can be applied including surgical excision, although high recurrence rates precludes its use as monotherapy. Several advanced surgical correction techniques including Z-plasty and W-plasty may be useful in repositioning scars. Other modalities that have been reported to improve scar cosmesis include cryosurgery, radiotherapy, lasers, and skin substitute grafts. Adjuvant postsurgical treatment modalities have reduced dramatically the recurrence rates associated with the removal of the scar. In this review of the literature the authors discuss evidence based data related to the abovementioned modalities and other topical and intralesional therapies including occlusion, compression, silicone, corticosteroids, interferons, imiquimod, resiquimod, tacrolimus, 5-fluorouracil, retinoids, as well as the role of several over-the-counter agents such as onion extract, vitamin E and the combination of hydrocortisone, vitamin E and silicone. Finally, they address newer modalities including vascular endothelial growth factor inhibitor, transforming growth factor-3, interleukin-10, mannose-6-phosphate, UVA-1, narrowband UVB, intense pulsed light and photodynamic therapy. Ultimately, the decision of choosing the most appropriate postexcisional management treatment should be taken by physicians on a case-by-case basis in order to obtain the best cosmetically acceptable results.


Asunto(s)
Cicatriz/terapia , Queloide/terapia , Complicaciones Posoperatorias/tratamiento farmacológico , Administración Cutánea , Productos Biológicos/administración & dosificación , Productos Biológicos/uso terapéutico , Cicatriz/tratamiento farmacológico , Cicatriz/etiología , Cicatriz/prevención & control , Cicatriz/radioterapia , Cicatriz/cirugía , Terapia Combinada , Técnicas Cosméticas , Criocirugía , Fármacos Dermatológicos/administración & dosificación , Fármacos Dermatológicos/clasificación , Fármacos Dermatológicos/uso terapéutico , Humanos , Queloide/tratamiento farmacológico , Queloide/etiología , Queloide/prevención & control , Queloide/radioterapia , Queloide/cirugía , Terapia por Láser , Fototerapia/métodos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/cirugía , Trasplante de Piel , Cirugía Plástica/métodos
16.
J Hazard Mater ; 154(1-3): 804-10, 2008 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-18079054

RESUMEN

Integrated biological processes involving the dissolution and subsequent precipitation have been used for the treatment of the spent material from the hydrogenation of vegetable oil containing a high-level of nickel. Our results show that nickel was successfully leached using Acidithiobacillus thiooxidans. The percentages of nickel leached using A. thiooxidans were higher than those obtained with dilute sulphuric acid solutions. Due to the physical characteristics of the residue, the best results were obtained when the leaching process was carried out using sulphuric acid biogenerated by an A. thiooxidans biofilm. The recovery of nickel from the leachates was performed at room temperature by precipitating with sulphide generated by Desulfovibrio cells. Indirect precipitation using sulphide generated in Desulfovibrio sp. cultures allowed the recovery of nickel as the very insoluble nickel sulphide.


Asunto(s)
Acidithiobacillus thiooxidans/metabolismo , Desulfovibrio/metabolismo , Níquel/química , Aceites de Plantas , Ácidos Sulfúricos/química , Administración de Residuos/métodos , Catálisis , Precipitación Química , Industria de Alimentos , Hidrogenación , Residuos Industriales , Níquel/metabolismo , Ácidos Sulfúricos/metabolismo
17.
Eur J Pediatr ; 166(12): 1211-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17611775

RESUMEN

Infectious gastroenteritis continues to be a leading cause of mortality and morbidity worldwide. The cornerstone of treatment remains replacement of water and electrolyte losses with oral rehydration solution. Until a few years ago, probiotics were discussed primarily in the context of alternative medicine, but they are now entering mainstream medical practice since a decrease of the severity and duration of infectious gastroenteritis in approximately 24 hours has been shown for some strains. Therefore, probiotics are a potential add-on therapy in acute gastro-enteritis. The shortening of the duration of diarrhoea and the reduction in hospital stay result in a social and economic benefit. Evidence found in viral gastroenteritis is more convincing than in bacterial or parasitic infection. Mechanisms of action are strain specific and only those commercial products for which there is evidence of clinical efficacy should be recommended. Timing of administration is also of importance. In acute gastroenteritis, there is evidence for efficacy of some strains of lactobacilli (e.g. Lactobacillus caseii GG and Lactobacillus reuteri) and for Saccharomyces boulardii. Probiotics are "generally regarded as safe", but side effects such as septicaemia and fungaemia have very rarely been reported in high-risk situations. Although most studies conclude in a statistically significant shortening of the duration of diarrhea, the clinical relevance of this finding is limited. In conclusion, selected strains of probiotics result in a statistically significant but clinically moderate benefit in shortening the duration of diarrhoea caused by acute infectious gastroenteritis.


Asunto(s)
Diarrea/etiología , Diarrea/prevención & control , Disentería/complicaciones , Disentería/prevención & control , Probióticos , Niño , Diarrea/terapia , Disentería/terapia , Humanos , Lactobacillus , Probióticos/uso terapéutico , Saccharomyces
18.
J Drugs Dermatol ; 5(1): 80-1, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16468299

RESUMEN

We describe a case of a 70-year-old woman who had been using a skin-lightening cream containing hydroquinone for a previous diagnosis of melasma. She presented a hyperpigmentation predominantly on her cheeks and eyebrows. The biopsy showed deposition of yellow-brown globules in the dermis. A diagnosis of exogenous ochronosis was made. An attempt of treatment using a Q-switched Nd:YAG laser has been initiated recently.


Asunto(s)
Hidroquinonas/efectos adversos , Ocronosis/inducido químicamente , Anciano , Femenino , Humanos
19.
J Biomed Mater Res B Appl Biomater ; 74(1): 589-600, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15793833

RESUMEN

Recently, numerous guide chambers for the treatment of injured nerves made up of different biomaterials have been designed, capable of hosting living cells or carrying neurotrophic or neuroactive substances to be directly released to the injured tissue. In this study, chitosan prostheses containing neurosteroids (progesterone and pregnenolone) were used for bridging a 10-mm gap in the rabbit facial nerve. Gas chromatography was used to quantify neurosteroid content in the prostheses prior to and after subcutaneous implantation at different periods of up to 60 days. The regeneration of the nerve fibers were evaluated at 15 and 45 days after axotomy by means of ultrastructural morphometric analysis. Different nerve fibers regenerative patterns were seen depending the groups studied and the analyzed stages. At 15 days after axotomy, the newly regenerating tissue revealed Schwann cells holding nonmyelinated nerve fiber bundles in an incipient and organized regenerative pattern. At 45 days, the regenerating tissue showed myelinated nerve fibers of different sizes, shapes, and myelin sheath thickness. Although the regeneration of the nerve fibers under neurosteroid treatment showed statistically significant differences in comparison with vehicle regenerated tissue, progesterone-loaded chitosan prostheses produced the best guided nerve regeneration response. These findings indicate that chitosan prostheses allowed regeneration of nerve fibers in their lumen, and when containing neurosteroids produced a faster guided nerve regeneration acting as a long-lasting release delivery vehicle.


Asunto(s)
Materiales Biocompatibles/química , Quitosano/química , Regeneración Nerviosa , Neuronas/ultraestructura , Pregnenolona/metabolismo , Progesterona/metabolismo , Animales , Sistemas de Liberación de Medicamentos , Nervio Facial/patología , Masculino , Microscopía Electrónica , Polímeros/química , Progesterona/química , Conejos , Regeneración , Esteroides/metabolismo , Factores de Tiempo
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