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1.
Int J Phytoremediation ; : 1-10, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38900190

RESUMEN

Plant growth on mine wastes is restricted by the lack of water, nutrients, phytotoxic responses and the absence of a seedbank. In a mesocosm study, we addressed the establishment of vegetation on metalliferous mine wastes from two seed mixtures. Besides the composition of the vegetation and the increase in plant cover and biomass over time, we studied concentrations of heavy metals in the shoot and analyzed the quantity of throughflow, its pH and EC to follow pollutant discharge. We hypothesized that the types of mine wastes and sown grasslands will affect species composition and the formation of a protective plant cover. Our platform was well-suited to study build-up and succession of a vegetation layer and its potential to stabilize mine wastes. However, the establishing community was less diverse than expected. The dilution of wastes increased species number and biomass, and we found a reduction of material discharge with increasing vegetation cover. Over time, drainage was reduced, while pH of the throughflow did not change. However, it was higher under the addition of greywater. Interestingly, the use of greywater led to a higher biomass in one mixture and slight changes in the chemistry of the throughflow and the plant matter.


Here, we present an integrative method to test the greening potentials of mine wastes. In the mesocosm approach different mine wastes, additives and seed mixtures can be screened and the potential of the establishing vegetation to reduce drainage and runoff may be addressed at the same time. Furthermore, analyses of pollutants in plants, soil substrates and drainage waters serve to study the phytoextraction and phytostabilization potentials of the established vegetation and their ecological services.

2.
Ecotoxicol Environ Saf ; 162: 505-513, 2018 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-30015197

RESUMEN

Restoration potential of mine wastes or approaches to improve soil conditions and to ameliorate phytotoxicity on these sites may be simulated in standardized greenhouse experiments. Plants can be cultivated side by side on materials from different origins in dilution series with defined admixtures of certain aggregates. Mine wastes used in the present study originated from Fenice Capanne (FC, Tuscany, Italy) and Altenberg (ALT, Saxony, Germany). Tailings of the Italian site contain high concentrations of lead, zinc, arsenic and sulphur while tin, wolfram, molybdenum and lithium are highly elevated in the German mine waste. We tested growth responses of five crop species and analyzed concentrations of various metals and nutrients in the shoot to evaluate the toxicity of the FC mine waste and found oilseed rape being the most and corn the least resistant crop. Interestingly, oilseed rape accumulated seven times higher levels of lead than corn without showing adverse effects on productivity. In a subsequent comparison of FC and ALT mine waste, we cultivated different species of buckwheat (Fagopyrum spec.), a fast growing genus that evolved in mountain areas and that has been shown to be tolerant to low pH and high concentrations of metals. We found that the FC mine waste was more toxic than the ALT substrate in F. tataricum and F. esculentum. However, lower admixtures of FC material (10%) resulted in stronger growth reductions than higher proportions (25%) of the mine waste which was primarily related to the slightly lower pH and higher availability of essential metals due to the admixture of sand. These results confirm the importance of managing the soil chemical and physical characteristics of wastelands and call for the development of assisted reclamation to prepare sites for regular biomass production.


Asunto(s)
Arsénico/toxicidad , Productos Agrícolas/efectos de los fármacos , Metales Pesados/toxicidad , Minería , Contaminantes del Suelo/toxicidad , Suelo/química , Azufre/toxicidad , Agricultura , Arsénico/análisis , Biomasa , Brassica rapa/efectos de los fármacos , Brassica rapa/crecimiento & desarrollo , Productos Agrícolas/crecimiento & desarrollo , Fagopyrum/efectos de los fármacos , Fagopyrum/crecimiento & desarrollo , Alemania , Residuos Industriales , Italia , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Azufre/análisis , Zea mays/efectos de los fármacos , Zea mays/crecimiento & desarrollo , Zinc/análisis , Zinc/toxicidad
3.
Nanotechnology ; 28(5): 055201, 2017 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-28008871

RESUMEN

Nanotextured surfaces provide an ideal platform for efficiently capturing and emitting light. However, the increased surface area in combination with surface defects induced by nanostructuring e.g. using reactive ion etching (RIE) negatively affects the device's active region and, thus, drastically decreases device performance. In this work, the influence of structural defects and surface states on the optical and electrical performance of InGaN/GaN nanorod (NR) light emitting diodes (LEDs) fabricated by top-down RIE of c-plane GaN with InGaN quantum wells was investigated. After proper surface treatment a significantly improved device performance could be shown. Therefore, wet chemical removal of damaged material in KOH solution followed by atomic layer deposition of only 10 [Formula: see text] alumina as wide bandgap oxide for passivation were successfully applied. Raman spectroscopy revealed that the initially compressively strained InGaN/GaN LED layer stack turned into a virtually completely relaxed GaN and partially relaxed InGaN combination after RIE etching of NRs. Time-correlated single photon counting provides evidence that both treatments-chemical etching and alumina deposition-reduce the number of pathways for non-radiative recombination. Steady-state photoluminescence revealed that the luminescent performance of the NR LEDs is increased by about 50% after KOH and 80% after additional alumina passivation. Finally, complete NR LED devices with a suspended graphene contact were fabricated, for which the effectiveness of the alumina passivation was successfully demonstrated by electroluminescence measurements.

4.
Intern Med J ; 46(8): 917-24, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27246246

RESUMEN

BACKGROUND/AIM: This study aims to examine differences between outer regional (OR) and remote/very remote (RVR) patients in northern Queensland, Australia in the times taken to receive various aspects of head and neck cancer management. METHODS: Our study prospectively recruited head and neck cancer patients presenting to three North Queensland regional hospitals from January 2009 to January 2011. Data on demographic and cancer-specific details, comorbidities and timing of presentation to various services, were collected using a self-administered questionnaire that included two questions in relation to possible reason for delays to health services. Multivariate linear regression analyses were conducted to assess the effects of various demographic characteristics on time delays. Survival and disease recurrence data were analysed in 2014. RESULTS: One hundred and fifty-eight patients participated. RVR patients had significantly longer median times between diagnosis and first treatment compared with OR patients (P = 0.015). Indigenous patients had significant delays from diagnosis to first treatment (P = 0.013) and visit to first specialist and treatment (P = 0.031) compared to non-Indigenous patients. Longer median times between symptoms and first treatment was associated with low income (P = 0.03) and lower education level (P = 0.04). Disease recurrence was higher for RVR patients compared with OR patients (P = 0.04), without significant differences in overall survival. Possible reasons for delays included patient and professional factors. CONCLUSION: Significant delays in various aspects of head and neck cancer management were associated with remoteness, Indigenous and socioeconomic status. While patient and professional factors could be addressed at local levels, sustainable improvement in outcomes requires a state and national level approach.


Asunto(s)
Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/terapia , Recurrencia Local de Neoplasia/epidemiología , Tiempo de Tratamiento/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Femenino , Hospitales , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Nativos de Hawái y Otras Islas del Pacífico , Estudios Prospectivos , Queensland , Derivación y Consulta , Salud Rural , Encuestas y Cuestionarios
5.
Gesundheitswesen ; 77(10): 820-6, 2015 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-26515711

RESUMEN

BACKGROUND: General cognitive abilities are still considered as the most important predictor of school achievement and success. Whether the high correlation (r=0.50) can be explained by other variables has not yet been studied. Learning behavior can be discussed as one factor that influences the relationship between general cognitive abilities and school achievement. METHODS: This study examined the relationship between intelligence, school achievement and learning behavior. Mediator analyses were conducted to check whether learning behavior would mediate the relationship between general cognitive abilities and school grades in mathematics and German. RESULTS: Statistical analyses confirmed that the relationship between general cognitive abilities and school achievement was fully mediated by learning behavior for German, whereas intelligence seemed to be the only predictor for achievement in mathematics. These results could be confirmed by non-parametric bootstrapping procedures. CONCLUSION: RESULTS indicate that special training of learning behavior may have a positive impact on school success, even for children and adolescents with low IQ.


Asunto(s)
Cognición/fisiología , Escolaridad , Inteligencia/fisiología , Aprendizaje/fisiología , Matemática/educación , Estudiantes/estadística & datos numéricos , Niño , Femenino , Alemania , Humanos , Pruebas de Inteligencia/estadística & datos numéricos , Lenguaje , Masculino , Solución de Problemas
6.
Diabetologia ; 56(2): 311-22, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23229156

RESUMEN

AIMS/HYPOTHESIS: Genome-wide association studies (GWAS) have identified numerous single-nucleotide polymorphisms associated with obesity, consequently implying a role in adipocyte biology for many closely residing genes. We investigated the functional relevance of such genes in human adipocytes. METHODS: We selected eight genes (BDNF, MAF, MTCH2, NEGR1, NPC1, PTER, SH2B1 and TMEM18) from obesity GWAS and analysed their effect in human adipogenesis using small interfering (si)RNA-mediated knockdown, their regulation by metabolic agents in adipocytes and pre-adipocytes, and gene expression in paired samples of human fat biopsies (68 non-obese, 165 obese) by quantitative real-time PCR. RESULTS: We show a two- to threefold upregulation of MAF, MTCH2 and NEGR1 and a two- to fourfold downregulation of BDNF and PTER during adipogenesis. Knockdown of BDNF (mean ± SEM; 83.8 ± 4.7% of control; p = 0.0002), MTCH2 (72.7 ± 9.5%; p = 0.0006), NEGR1 (70.2 ± 5.7%; p < 0.0001) and TMEM18 (70.8 ± 6.1%; p < 0.0001) significantly inhibited adipocyte maturation, while knockdown of the other proteins had no effect. Insulin slightly induced MAF (1.65-fold; p = 0.0009) and MTCH2 (1.72-fold; p < 0.0001), while it suppressed BDNF (59.6%; p = 0.0009), NEGR1 (58.0%; p = 0.0085) and TMEM18 (69.3%; p = 0.0377) in adipocytes. The synthetic glucocorticoid dexamethasone suppressed MAF (45.7%; p = 0.0022), BDNF (66.6%; p = 0.0012) and TMEM18 (63.5%; p = 0.0181), but induced NEGR1 (3.2-fold; p = 0.0117) expression. Furthermore, MTCH2, NEGR1 and TMEM18 were differentially expressed in subcutaneous and visceral adipose tissue. TMEM18 expression was decreased in the adipose tissue of obese patients, and negatively correlated with anthropometric variables and adipocyte size. CONCLUSIONS/INTERPRETATION: Our results imply a regulatory role for TMEM18, BDNF, MTCH2 and NEGR1 in adipocyte differentiation and biology. In addition, we show a variation of MAF expression during adipogenesis, while NPC1, PTER and SH2B1 were not regulated.


Asunto(s)
Adipocitos/metabolismo , Estudio de Asociación del Genoma Completo/métodos , Obesidad/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Tejido Adiposo/metabolismo , Factor Neurotrófico Derivado del Encéfalo/genética , Proteínas Portadoras/genética , Moléculas de Adhesión Celular Neuronal/genética , Femenino , Proteínas Ligadas a GPI/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular , Masculino , Glicoproteínas de Membrana/genética , Proteínas de la Membrana/genética , Proteínas de Transporte de Membrana Mitocondrial/genética , Proteína Niemann-Pick C1 , Proteínas Proto-Oncogénicas c-maf/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
7.
Br J Cancer ; 107(3): 422-8, 2012 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-22782342

RESUMEN

BACKGROUND: Established prognostic factors are of limited value to predict long-term survival and benefit from metastasectomy in advanced melanoma. This study aimed to identify prognostic factors in patients with distant metastasis. METHODS: We analysed overall survival of 855 institutional melanoma patients with distant metastasis by bivariate Kaplan-Meier survival probabilities and multivariate Cox hazard regression analysis. RESULTS: Serum lactate dehydrogenases (LDH), S100B, the interval between initial diagnosis and occurrence of distant metastasis, the site of distant metastases, and the number of involved distant sites were significant independent prognostic factors in both bivariate and multivariate analyses. Visceral metastases other than lung (hazard ratio (HR) 1.8), elevated S100B (HR 1.7) and elevated LDH (HR 1.6) had the highest negative impact on survival. Complete metastasectomy was likewise an independent prognostic factor in multivariate analysis. This treatment was associated with favourable survival for patients with normal LDH and S100B values (5-year survival, 37.2%). CONCLUSION: The serum markers LDH and S100B were both found to be prognostic factors in melanoma patients with distant metastasis. Furthermore, complete metastasectomy had an independent favourable prognostic impact in particular for the patient subgroup with normal LDH and S100B values.


Asunto(s)
Biomarcadores de Tumor/sangre , Lactato Deshidrogenasas/sangre , Melanoma/sangre , Factores de Crecimiento Nervioso/sangre , Proteínas S100/sangre , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Melanoma/enzimología , Melanoma/patología , Melanoma/cirugía , Metastasectomía/métodos , Persona de Mediana Edad , Análisis Multivariante , Metástasis de la Neoplasia , Pronóstico , Subunidad beta de la Proteína de Unión al Calcio S100 , Análisis de Supervivencia
8.
Eur J Vasc Endovasc Surg ; 39(5): 606-11, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20122854

RESUMEN

OBJECTIVES: The aims of this study were to investigate the change in maximum diameter of ectatic popliteal arteries during ultrasound surveillance and assess clinical predictors of their expansion. METHODS: Over a ten year period 67 patients with ectasia affecting one (n = 1) or both (n = 66) popliteal arteries entered this surveillance study. Patients were followed for a median of 3.1 years, at a median scan interval of 7.6 months. RESULTS: Growth of ectatic popliteal arteries was typically slow (<1 mm/yr). Initial artery diameter at entry to the study was not found to be predictive of subsequent growth. Seven patients followed for a median of 2 years had an expansion in popliteal artery diameter to >or=20 mm during follow-up. All of these patients had undergone aneurysm repairs at other arterial sites and none of them had diabetes. These participants also had a significantly higher rate of previous intervention of the contralateral popliteal artery in comparison to those that did not reach the 20 mm threshold (p < 0.001). Growth profiles of arteries that underwent significant expansion during surveillance were frequently characterised by a staccato pattern. CONCLUSIONS: Expansion of ectatic popliteal arteries is typically slow but difficult to predict. Trends observed in this study suggest that patients with extra-popliteal aneurysms, patients with previously treated contralateral popliteal artery ectasia and those who are not diabetics may be more prone to significant expansion. Further studies are required to validate these potential growth predictors.


Asunto(s)
Aneurisma/diagnóstico por imagen , Arteria Poplítea/diagnóstico por imagen , Anciano , Dilatación Patológica , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Medición de Riesgo , Factores de Riesgo , Tromboembolia/diagnóstico por imagen , Trombosis/diagnóstico por imagen , Factores de Tiempo , Ultrasonografía Doppler Dúplex
9.
Nanoscale ; 10(18): 8385-8390, 2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29696279

RESUMEN

Preparation of pre-patterned alumina substrates using bottom-up techniques compatible with nanotechnology applications is still a challenge. We present a novel methodology to achieve superior order in 'anodic' alumina with large interpore distances by a convenient one-step anodization process. The use of transparent insulators renders such anodic layers applicable as templates for nanostructured photovoltaic or photoelectrochemical devices.

10.
J Invest Dermatol ; 102(5): 695-9, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8176250

RESUMEN

Different pigmentary characteristics as well as different parameters of sun exposure have previously been identified as risk factors for developing cutaneous melanoma. The aim of the present study was to identify significant risk factors, determine the related magnitude of their estimated relative risks, and define criteria for the detection of persons at risk. Five hundred thirteen melanoma patients and 498 controls matched for age and sex underwent a whole-body examination for the number and type of melanocytic lesions and were interviewed on ultraviolet exposure and other potential risk factors. The total number of common melanocytic nevi on all body sites represented the most important risk factor in multiple logistic regression analysis with a relative risk of 7.6 for subjects with more than 100 versus no more than 10 melanocytic nevi. Other significant independent risk factors were the number of atypical melanocytic nevi (relative risk, 6.1 for at least 5 melanocytic nevi versus none), the number of actinic lentigines (relative risk, 3.5 for many versus none), hair color, skin type, and reported melanocytic nevus growth. No single parameter of sun exposure was significantly related to melanoma risk in the multivariate analysis. Groups with an estimated relative risk between 1 and 121.0 were distinguished by considering common and atypical melanocytic nevi as well as actinic lentigines as the decisive criteria. In conclusion, even without any information on the case history, whole-body examination and diagnosis of pigmented lesions was found to be an effective strategy for identifying persons at risk of developing melanoma. Furthermore, clinical recognition of at least 5 atypical melanocytic nevi without histologic examination is a key for identifying subjects at high risk.


Asunto(s)
Melanoma/epidemiología , Neoplasias Cutáneas/epidemiología , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Análisis de Regresión , Factores de Riesgo
11.
J Invest Dermatol ; 102(5): 700-5, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8176251

RESUMEN

Several case-control studies identified common and atypical melanocytic nevi as major risk indicators for the development of cutaneous melanoma. The present investigation was planned to detect factors associated with the prevalence of these melanoma risk markers. Whole-body examination findings and interview data of 513 melanoma patients and 498 age- and sex-matched control subjects were analyzed. Existence of more than 50 common melanocytic nevi and the presence of atypical melanocytic nevi were significantly related to age and gender, with significantly elevated relative risk for their prevalence before the age of 60 and in males. Additionally, sunburns before the age of 20 were significantly associated with both more than 50 common melanocytic nevi (relative risk = 1.7) and the presence of atypical melanocytic nevi (relative risk = 1.5). Actinic lentigines were found more frequently with increasing age, and the presence of actinic lentigines was significantly related to a tendency of freckling in adolescence (relative risk = 2.0) and to two or more sunburns after the age of 20 (relative risk = 1.6). In conclusion, sunburns before the age of 20 contribute to the development of multiple melanocytic nevi and atypical melanocytic nevi. In adulthood, this type of sun exposure is associated with the development of actinic lentigines. The relative risk of developing cutaneous melanoma increases in association with the development of these benign melanocytic lesions.


Asunto(s)
Lentigo/epidemiología , Nevo Pigmentado/epidemiología , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Color del Cabello , Humanos , Masculino , Melanoma/etiología , Melanosis/epidemiología , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Prevalencia , Piel/patología , Neoplasias Cutáneas/etiología
12.
Am J Cardiol ; 71(8): 720-6, 1993 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-8447272

RESUMEN

To evaluate the significance of clinical, hemodynamic and electrocardiographic risk factors in idiopathic dilated cardiomyopathy 94 patients were followed prospectively for 49 +/- 37 months. During follow-up, 30 patients died, 13 died suddenly, 13 died of congestive heart failure and 4 of other causes. Follow-up was completed in 85 patients, and overall cardiac mortality was 31%. Univariate analysis revealed left ventricular ejection fraction among 20 variables as the major indicator of risk of both cardiac death of all causes and sudden cardiac death separately. Multivariate overall analysis determined 3 independent risk factors in the following order for all causes of cardiac death: Ventricular pairs > 40/24 hours (RR 7.2, p < 0.0001), left ventricular ejection fraction < or = 35% (RR 6.5, p < 0.001) and first- or second-degree atrioventricular (AV) block (RR 3.1, p < 0.05). In the subset of patients with ejection fraction < or = 35% ventricular pairs > 40 per 24 hours (RR 10.7, p < 0.001), AV block (RR 3.9, p < 0.05), and the missing administration of vasodilators (RR 3.3, p < 0.05) were the most important. The chief risk factors for sudden cardiac death were age (RR 7.4, p < 0.01) and AV block (RR 4.6, p < 0.05) by adjustment for age, and ejection fraction < or = 35% (RR 7.1, p < 0.01) and AV block (RR 4.2, p < 0.05) if not adjusted for age. A differentiation into 4 risk groups was attempted. The additional independent prognostic importance of AV block was shown, especially in combination with reduced ejection fraction or a high incidence of ventricular pairs.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Cardiomiopatía Dilatada/complicaciones , Muerte Súbita Cardíaca , Bloqueo Cardíaco/complicaciones , Adulto , Arritmias Cardíacas/complicaciones , Arritmias Cardíacas/tratamiento farmacológico , Fibrilación Atrial/complicaciones , Cardiomiopatía Dilatada/fisiopatología , Fármacos Cardiovasculares/uso terapéutico , Femenino , Estudios de Seguimiento , Bloqueo Cardíaco/fisiopatología , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Análisis de Supervivencia
13.
Cancer Lett ; 105(1): 1-4, 1996 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-8689623

RESUMEN

An immunohistochemical assay, using 96-well microtiter plates and based on the avidin-biotin peroxidase reaction, was developed for the quantitation of E-cadherin and CEA expression on HT-29 and SW620 colon carcinoma cells. The optical density of the generated dye was measured after solubilization with alkaline SDS solution. The staining procedure was evaluated with respect to reproducibility (coefficient of variation and intra-class correlation coefficient). On HT-29 cells the level of agreement for both E-cadherin and CEA were substantial, on SW620 cells almost perfect. The method allows testing compounds for their differentiation inducing capacity in screening programmes on the basis of protein marker expression.


Asunto(s)
Cadherinas/metabolismo , Antígeno Carcinoembrionario/metabolismo , Carcinoma/metabolismo , Neoplasias del Colon/metabolismo , Carcinoma/patología , Neoplasias del Colon/patología , Dimetilsulfóxido/farmacología , Humanos , Inmunoensayo , Inmunohistoquímica , Células Tumorales Cultivadas
14.
Arch Dermatol ; 129(9): 1146-51, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8363398

RESUMEN

BACKGROUND AND DESIGN: A variety of therapeutic regimens has been used in keloids and hypertrophic scars with unsatisfactory final results. Application of cryosurgery could be beneficial since it was reported to produce less scarring after treatment of skin tumors compared with other surgical procedures. We performed a prospective consecutive trial of randomly enrolled case series including 32 months of average follow-up to assess the outcomes of cryosurgical treatment in keloids and hypertrophic scars and to determine factors influencing the therapeutic result. Ninety-three white patients, aged 10 to 79 years (median age, 26 years) with keloids (n = 55; median duration, 36 months; median size, 4 cm2) and with hypertrophic scars (n = 38; median duration, 12 months; median size, 2 cm2) were treated using the contact method. One freeze-thaw cycle of 30 seconds per lesion and session was employed, and, if needed, treatment was repeated every 20 to 30 days. RESULTS: Excellent responses (ER) were recorded in 30 subjects (32.3%), good responses (GR) in 27 (29.0%), poor responses (PR) in 27 (29.0%), while nine subjects (9.7%) did not respond at all. Hypertrophic scars responded better (n = 38; GR to ER, 76.3%) than keloids (n = 55; GR to ER, 50.9%; P < .005; odds ratio, 6.92). No progressions or recurrences occurred. Histologically, neovascularization, loss of the anarchic arrangement of collagen bundles, increased fibroblasts in a stroma running parallel to the skin surface, and mononuclear cells mostly arranged at the perivascular area were found in clinically responding lesions. Improved responses were detected in subjects treated with three or more sessions (n = 57; GR to ER, 78.9%) compared with subjects treated once or twice (n = 36; GR to ER, 33.3%; P < .001; odds ratio, 13.68). The cryosurgical treatment was generally well tolerated, with local pain during freezing and/or shortly after treatment (n = 32, 34.4%) and hypopigmentation or hyperpigmentation (n = 11, 11.8%) being the most frequent side effects. CONCLUSIONS: Cryosurgery was found effective and safe in keloids and, especially, in hypertrophic scars, in an open, uncontrolled study. Satisfactory results could be obtained after at least three cryosurgical sessions of 30 seconds each, applied once monthly using the contact method of treatment.


Asunto(s)
Cicatriz Hipertrófica/cirugía , Criocirugía , Queloide/cirugía , Adolescente , Adulto , Anciano , Niño , Cicatriz Hipertrófica/patología , Femenino , Estudios de Seguimiento , Humanos , Queloide/patología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Estudios Prospectivos , Análisis de Regresión , Resultado del Tratamiento
15.
Arch Dermatol ; 132(11): 1323-9, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8915310

RESUMEN

BACKGROUND AND DESIGN: To elucidate the role of lymphocyte/endothelial cell interactions in patients with Adamantiades-Behçet disease (ABD), we studied 16 patients of German and Turkish nationality (aged 18-57 years), all with active ABD, and 12 healthy volunteers (controls) of similar age and nationality. Peripheral blood lymphocytes (PBL) of patients were coincubated with human dermal microvascular endothelial cells (HDMEC) and human keratinocytes (HK) in vitro; interactions of PBL with HDMEC and HK were investigated using an established fluorometric assay. Interactions of patients' PBL with HDMEC, HK, or both were the main outcome measures. RESULTS: A significant increase of fluorescence with increasing PBL/HDMEC ratios was seen in patients and controls (P < .001); patients showed a significantly higher increase of fluorescence at higher PBL/HDMEC ratios (P < .05). The PBL/HK coincubation did not show significant alterations compared with the basal fluorescence signals of HK monolayers alone. Peripheral blood lymphocyte and HDMEC fluorescence values that were more than 2 SDs of controls (defined as positive result of assay) were found in a significantly higher number of patients with 2 or more active symptoms at the time of investigation (83%) compared with patients with only 1 active symptom (10%) (P = .008). Other clinical data did not correlate with the results of the PBL/HDMEC coincubation assay. CONCLUSIONS: Our results indicate enhanced in vitro interaction of PBL from patients with ABD with HDMEC, which was additionally shown to be a marker of the activity of the disease.


Asunto(s)
Síndrome de Behçet/fisiopatología , Comunicación Celular , Endotelio Vascular/citología , Linfocitos/fisiología , Piel/irrigación sanguínea , Adolescente , Adulto , Células Cultivadas , Femenino , Humanos , Queratinocitos/fisiología , Masculino , Microcirculación , Persona de Mediana Edad
16.
Recent Results Cancer Res ; 139: 323-36, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7597301

RESUMEN

The role of elective lymph node dissection (ELND) in clinical stage I malignant melanoma continues to be controversial. We present a matched pair analysis of 375 patients treated in the Department of Dermatology in Kassel between 1979 and 1991 by wide local excision (WLE) plus ELND. Multivariate analysis revealed tumor thickness, level of invasion, age, sex, and localization as independent prognostic factors, and 375 patients treated by WLE alone were matched as controls to the patients treated by ELND and WLE. There was no significant benefit from WLE plus ELND compared to WLE alone in the total group as shown by the 5-year survival rates (87.3% versus 86.4%) and 10-year survival rates (80.1% versus 77.82%). Increased survival rates were noted for tumor thicknesses 1.51-4.0 mm for the WLE plus ELND group, as shown by the 10-year survival rates of 73.1% versus 60.3%. However, these data were not significant (p = 0.14). Disease-free survival rates were significantly higher in the group treated by additional ELND for all tumor thicknesses (p < 0.05) and even more in intermediate tumor thicknesses of 1.51-4.0 mm (p < 0.001). A significant benefit of elective lymph node dissection was detected for malignant melanoma of the trunk (all tumor thicknesses), as shown by the 5-year survival rates of 92.0% versus 79.7% and 10-year survival rates of 80.4% versus 45.16% (p < 0.05). Malignant melanoma of the extremities revealed no significant differences in survival rates. We conclude that there is a certain benefit from ELND in clinical stage I malignant melanoma for tumor thicknesses of 1.51-4.00 mm. Especially in malignant melanoma of the trunk, WLE plus ELND was more beneficious than WLE alone.


Asunto(s)
Escisión del Ganglio Linfático , Melanoma/cirugía , Neoplasias Cutáneas/cirugía , Análisis Actuarial , Adulto , Dorso , Estudios de Casos y Controles , Supervivencia sin Enfermedad , Extremidades , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática/prevención & control , Masculino , Melanoma/mortalidad , Melanoma/patología , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/patología , Tasa de Supervivencia , Resultado del Tratamiento
17.
Trans R Soc Trop Med Hyg ; 91(4): 382-6, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9373626

RESUMEN

Surveys were conducted of adult and immature mosquitoes in an area undergoing oil palm development in north Sarawak. Point prevalence data from 2 sites were collected annually, coinciding with annual phases of forest clearing, burning/cultivation, and maintenance. Major habitat perturbation during the forest/clearing transition shifted the major mosquito faunal equilibrium in terms of species composition, relative density and occurrence. Analyses of variance showed that the mean numbers of 4 species of Anopheles decreased significantly after forest clearing. Relative densities of immature stages decreased after forest clearing, but A. letifer and Culex tritaeniorhynchus remained relatively unchanged after the second year. Comparisons with the pre-development forest stage showed that the reductions in person-biting rates, adult survival and combined entomological inoculation rates (EIR) of A. donaldi and A. letifer decreased the risk of malaria transmission by 90% over the 4 years period. Concomitant reductions in EIR and annual malaria incidence were also correlated. This study highlighted the 'law of unintended consequences', since 2 contrasting effects were observed: reduction of malaria vectors but concomitant increase of dengue vectors.


Asunto(s)
Culicidae/fisiología , Agricultura Forestal , Insectos Vectores , Animales , Femenino , Malaria/transmisión , Malasia , Masculino , Aceites de Plantas , Densidad de Población , Factores de Tiempo
18.
Photochem Photobiol ; 70(2): 269-74, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10461467

RESUMEN

There is strong evidence that sun exposure during childhood and adolescence plays an important role in the etiology of skin cancer, in particular cutaneous melanoma. Between the age of 6 and 18, most children and adolescents will spend around 200 days per year at school and may receive a substantial fraction of their daily total solar ultraviolet radiation (UVR) exposure while at school. This study estimated the average daily erythemally effective dose of 70 grade 8 students from a high school in Townsville during 5 school days in July 1998. Through UV measurements of shade locations at the school and a combination of frequency counts and a questionnaire of grade 8 students, it was possible to determine the fraction of solar UVR reaching under the shade structures during lunch breaks and routine outdoor activities. Also, a routinely operating UV-Biometer provided the annual variation of the daily dose that was used to calculate exposure levels for the 70 students. Our results suggest that up to 47% of the daily total dose fell within the time periods where students were outdoors during school hours. For students not seeking shade structures during the breaks (which usually was the case when involved in sport activities such as basketball or soccer), the average daily dose could have been as high as 14 SED (standard erythemal dose). Using results from the questionnaire of 70 grade 8 students, their average annual dose while at school was 414 SED or 2 SED per school day. However, the distribution of average daily erythemal effective dose per grade 8 student over the whole year showed that on 31% of all school days in 1998, this dose was exceeded. Because most previous attempts to change arguably poor sun-protective behavior of young Australian children and adolescents at school showed little success, one way of decreasing the amount of harmful UVR reaching unprotected skin is the more careful design of shade structures at schools.


Asunto(s)
Estudiantes , Luz Solar/efectos adversos , Adolescente , Niño , Femenino , Humanos , Masculino , Melanoma/etiología , Queensland , Factores de Riesgo , Instituciones Académicas , Neoplasias Cutáneas/etiología , Encuestas y Cuestionarios
19.
Oncol Rep ; 2(3): 469-72, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-21597761

RESUMEN

Recently we demonstrated that, in vitro, prothymosin alpha 1 (ProT alpha), a polypeptide from calf thymus, was able to enhance the deranged tumoristatic activity of peripheral blood monocytes from melanoma patients. Now we report, that the thymic preparation Thymex-L significantly enhanced the level of depressed monocyte activity from 19% to 26%, whereas in normal donor groups no significant change of basal activity (35%) was seen. Although the improvement of median levels of killer cell activity was found to be independent from the disease stage, the Thymex-L effect was only statistically significant in stage I and melanoma patients after chemotherapy. In contrast to ProT alpha, Thymex-L did not further enhance monocyte-mediated cytotoxicity when it was applied in combination with rIFN-gamma. However, after stimulation with rIFN-gamma, the median level of TNF-alpha secretion by melanoma monocytes significantly increased (about 2-fold) when preincubated with Thymex-L. These results indicate that depressed monocyte functions in selected melanoma patients may be partially improved by Thymex-L.

20.
Melanoma Res ; 5(3): 189-94, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7640521

RESUMEN

The role of elective lymph node dissection (ELND) in primary malignant melanoma is still controversial. Our purpose in this study was to evaluate the benefit from ELND on survival and disease-free survival in malignant melanoma of the trunk and extremities. We performed a matched-pair analysis on 750 patients. There was no significant benefit from wide local excision (WLE) plus ELND compared with WLE in the total group. Increased survival rates were noted for tumour thicknesses of 1.51-4.0 mm for the WLE+ELND group, as shown by 10-year survival rates of 73.1% vs 60.3% (p = 0.14). A significant benefit of ELND was detected for malignant melanoma of the trunk (p < 0.05). Disease-free survival rates were significantly higher in the collective treated by additional ELND for all tumour thicknesses (p < 0.05) and even more in intermediate tumour thicknesses of 1.51-4.0 mm (p < 0.001). Our data give further support that ELND may be valuable in improving the prognosis in case of malignant melanoma of intermediate Breslow thickness.


Asunto(s)
Escisión del Ganglio Linfático , Melanoma/cirugía , Adulto , Supervivencia sin Enfermedad , Extremidades , Femenino , Humanos , Masculino , Análisis por Apareamiento , Persona de Mediana Edad , Estudios Retrospectivos , Análisis de Supervivencia , Tasa de Supervivencia
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