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1.
Cureus ; 16(7): e65249, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39184733

RESUMEN

Epidermodysplasia verruciformis (EV) is a rare, lifelong, autosomal recessive genodermatosis characterized by susceptibility to certain human papillomavirus (HPV) types and increased risk of skin cancer. This report describes a 22-year-old male presenting with multiple flat erythematous papules on the trunk and extremities. Histopathological examination of a skin biopsy revealed features consistent with EV, including hypergranulosis, hyperkeratosis, and acanthosis, with notable keratohyalin granules and perinuclear vacuolization of keratinocytes. No mitotic activity or cellular atypia was observed. This case underscores the importance of early diagnosis and management of EV, which includes genetic counseling, photoprotection, and regular monitoring for premalignant lesions. Treatment options, ranging from pharmacologic interventions to surgical excision, aim to mitigate the risk of malignant transformation. This report highlights the clinical and histopathological presentation of EV, contributing to the understanding and management of this rare genodermatosis.

2.
J Taibah Univ Med Sci ; 16(6): 843-848, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34899128

RESUMEN

OBJECTIVES: Patients with vitiligo experience emotional and psychological stress as they undergo long-term therapy. The debilitating psychosocial effects of this disease on patients' quality of life is well-documented. This study evaluates the effect of the introduction of narrow-band ultraviolet-B (NB-UVB) therapy on the quality of life of patients with vitiligo in Almadinah Almunawwarah, KSA. METHODS: Thirty-eight patients from the main dermatology center of Ohud Hospital, Almadinah Almunawwarah, were interviewed between June 2017 and March 2019 using the Dermatology Life Quality Index (DLQI) questionnaire. The interviews were conducted before and one year after the course of NB-UVB therapy, which was added as a new treatment modality to the basic therapeutic regimen of topical medications. RESULTS: The patients' response to vitiligo therapy was positive. The overall patient satisfaction score regarding the NB-UVB therapy was as high as 9.1 out of 10. The initial overall DLQI score (5.67 ± 0.90) markedly decreased after the NB-UVB therapy (3.08 ± 0.56), indicating a significant improvement. The patients' adherence to the follow-up visits also improved. CONCLUSION: NB-UVB therapy is effective in alleviating psychological stress and improving the quality of life of patients with vitiligo.

3.
J Thromb Haemost ; 15(6): 1167-1179, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28397397

RESUMEN

Essentials Recombinant factor VIII (rFVIII) Fc fusion protein has a 1.5-fold longer half-life than rFVIII. Five orthogonal methods were used to characterize the structure of rFVIIIFc compared to rFVIII. The C-terminal Fc fusion does not perturb the structure of FVIII in rFVIIIFc. The FVIII and Fc components of rFVIIIFc are flexibly tethered and functionally independent. SUMMARY: Background Fusion of the human IgG1 Fc domain to the C-terminal C2 domain of B-domain-deleted (BDD) factor VIII (FVIII) results in the recombinant FVIII Fc (rFVIIIFc) fusion protein, which has a 1.5-fold longer half-life in humans. Objective To assess the structural properties of rFVIIIFc by comparing its constituent FVIII and Fc elements with their respective isolated components, and evaluating their structural independence within rFVIIIFc. Methods rFVIIIFc and its isolated FVIII and Fc components were compared by the use of hydrogen-deuterium exchange mass spectrometry (HDX-MS). The structure of rFVIIIFc was also evaluated by the use of X-ray crystallography, small-angle X-ray scattering (SAXS), and electron microscopy (EM). The degree of steric interference by the appended Fc domain was assessed by EM and surface plasmon resonance (SPR). Results HDX-MS analysis of rFVIIIFc revealed that fusion caused no structural perturbations in FVIII or Fc. The rFVIIIFc crystal structure showed that the FVIII component is indistinguishable from published BDD FVIII structures. The Fc domain was not observed, indicating high mobility. SAXS analysis was consistent with an ensemble of rigid-body models in which the Fc domain exists in a largely extended orientation relative to FVIII. Binding of Fab fragments of anti-C2 domain antibodies to BDD FVIII was visualized by EM, and the affinities of the corresponding intact antibodies for BDD FVIII and rFVIIIFc were comparable by SPR analysis. Conclusions The FVIII and Fc components of rFVIIIFc are structurally indistinguishable from their isolated constituents, and show a high degree of structural independence, consistent with the functional comparability of rFVIIIFc and unmodified FVIII.


Asunto(s)
Factor VIII/química , Hemofilia A/tratamiento farmacológico , Fragmentos Fc de Inmunoglobulinas/química , Proteínas Recombinantes de Fusión/química , Cristalografía por Rayos X , Factor VIII/administración & dosificación , Células HEK293 , Semivida , Hemofilia A/inmunología , Hemorragia , Humanos , Fragmentos Fc de Inmunoglobulinas/administración & dosificación , Cinética , Espectrometría de Masas , Microscopía Electrónica , Fragmentos de Péptidos/química , Dominios Proteicos , Proteínas Recombinantes de Fusión/administración & dosificación , Dispersión del Ángulo Pequeño , Resonancia por Plasmón de Superficie , Difracción de Rayos X
4.
Phys Med Biol ; 55(3): 761-81, 2010 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-20071772

RESUMEN

We present a nanodosimetric model for predicting the yield of double strand breaks (DSBs) and non-DSB clustered damages induced in irradiated DNA. The model uses experimental ionization cluster size distributions measured in a gas model by an ion counting nanodosimeter or, alternatively, distributions simulated by a Monte Carlo track structure code developed to simulate the nanodosimeter. The model is based on a straightforward combinatorial approach translating ionizations, as measured or simulated in a sensitive gas volume, to lesions in a DNA segment of one-two helical turns considered equivalent to the sensitive volume of the nanodosimeter. The two model parameters, corresponding to the probability that a single ion detected by the nanodosimeter corresponds to a single strand break or a single lesion (strand break or base damage) in the equivalent DNA segment, were tuned by fitting the model-predicted yields to previously measured double-strand break and double-strand lesion yields in plasmid DNA irradiated with protons and helium nuclei. Model predictions were also compared to both yield data simulated by the PARTRAC code for protons of a wide range of different energies and experimental DSB and non-DSB clustered DNA damage yield data from the literature. The applicability and limitations of this model in predicting the LET dependence of clustered DNA damage yields are discussed.


Asunto(s)
Daño del ADN/efectos de la radiación , ADN/efectos de la radiación , Modelos Genéticos , Nanotecnología/métodos , Radiometría/métodos , Algoritmos , Simulación por Computador , Roturas del ADN de Doble Cadena/efectos de la radiación , Helio/efectos adversos , Método de Montecarlo , Nanotecnología/instrumentación , Plásmidos/efectos de la radiación , Probabilidad , Protones/efectos adversos , Radiometría/instrumentación , Reproducibilidad de los Resultados , Saccharomyces cerevisiae , Programas Informáticos
5.
Radiat Prot Dosimetry ; 122(1-4): 451-4, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17158786

RESUMEN

We present the first results of our attempts to correlate yields of ionisation clusters in a gas model of DNA and corresponding double-strand break (DSB) yields in irradiated plasmids, using a simple statistical model of DNA lesion formation. Based on the same statistical model, we also provide a comparison of simulated nanodosimetric data for electrons and published DSB yields obtained with the PARTRAC code.


Asunto(s)
Daño del ADN , ADN/química , ADN/efectos de la radiación , Modelos Químicos , Modelos Genéticos , Nanotecnología/métodos , Radiometría/métodos , Algoritmos , Simulación por Computador , Bases de Datos Factuales , Relación Dosis-Respuesta en la Radiación , Microquímica/métodos , Proyectos Piloto , Dosis de Radiación
6.
Int J Radiat Biol ; 81(1): 41-54, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15962762

RESUMEN

PURPOSE: To measure the yield of DNA strand breaks and clustered lesions in plasmid DNA irradiated with protons, helium nuclei, and y-rays. MATERIALS AND METHODS: Plasmid DNA was irradiated with 1.03, 19.3 and 249 MeV protons (linear energy transfer = 25.5, 2.7, and 0.39 keV microm(-1) respectively), 26 MeV helium nuclei (25.5 keV microm) and gamma-rays (137Cs or 60Co) in phosphate buffer containing 2 mM or 200 mM glycerol. Single-and double-strand breaks (SSB and DSB) were measured by gel electrophoresis, and clustered lesions containing base lesions were quantified by converting them into irreparable DSB in transformed bacteria. RESULTS: For protons, SSB yield decreased with increasing LET (linear energy transfer). The yield of DSB and all clustered lesions seemed to reach a minimum around 3 keV microm(-1). There was a higher yield of SSB, DSB and total clustered lesions for protons compared to helium nuclei at 25.5 keV microm(-1). A difference in the yields between 137Cs and 60Co gamma-rays was also observed, especially for SSB. CONCLUSION: In this work we have demonstrated the complex LET dependence of clustered-lesion yields, governed by interplay of the radical recombination and change in track structure. As expected, there was also a significant difference in clustered lesion yields between various radiation fields, having the same or similar LET values, but differing in nanometric track structure.


Asunto(s)
Partículas alfa/efectos adversos , Daño del ADN , ADN/efectos de la radiación , Rayos gamma/efectos adversos , Protones/efectos adversos , Traumatismos por Radiación/etiología , ADN Bacteriano , Transferencia Lineal de Energía/efectos de la radiación , Modelos Biológicos , Plásmidos/efectos de la radiación
7.
Arch Pediatr ; 7(5): 509-12, 2000 May.
Artículo en Francés | MEDLINE | ID: mdl-10855390

RESUMEN

BACKGROUND: Disinfectants for medical devices are uncommonly a cause of iatrogenic adverse effects. Nevertheless, when misused, they can induce severe complications. Three cases of acute respiratory distress in newborns probably induced by glutaraldehyde are reported. CASE REPORTS: Three children born by Caesarean section between 8 and 19 May 1999 in the same hospital presented acute respiratory distress requiring hospitalization in the neonatal intensive care unit; one child was premature. The clinical appearance, which was initially normal, deteriorated with a respiratory distress in 30 to 60 minutes. Recovery was uneventful in all cases. The diagnosis considered was a hyaline membrane disease. The enquiry conducted after this cluster onset identified, as a main contributing factor, the disinfection procedure recently introduced in the surgical theater. CONCLUSION: Review of toxicologic data on glutaraldehyde shows this is a highly irritating chemical for the respiratory tract, even at low concentrations. Clinical and radiologic features in these three neonates are compatible with a pulmonary sub-edema on an immature alveolar setting. The hypothesis proposed is that glutaraldehyde, the active ingredient of the biocidal formula used to disinfect the respiratory masks, was massively desorbed from the rubber and foam of which masks are made.


Asunto(s)
Desinfectantes/efectos adversos , Glutaral/efectos adversos , Máscaras/microbiología , Síndrome de Dificultad Respiratoria del Recién Nacido/inducido químicamente , Equipo Reutilizado , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Unidades de Cuidado Intensivo Neonatal , Masculino
8.
Rev. Hosp. Clin. Fac. Med. Univ. Säo Paulo ; 46(2): 59-62, mar.-abr. 1991. ilus, tab
Artículo en Portugués | LILACS | ID: lil-108319

RESUMEN

Foi realizada a dosagem biologica de produtos comerciais de heparina e de amostras do Primeiro Padrao Nacional Argentino de Heparina da mucosa intestinal suina. Os resultados foram comparados com o Quarto Padrao Internacional. Foi empregado o metodo de Reinert e Winterstein, modificado preconizado pelas Farmacopeias Americana e Brasileira. Foram discutidas as metodologias descritas na literatura e indicada a importancia destas para a avaliacao da atividade anticoagulante das heparinas nao-fracionadas e das de baixo peso molecular.


Asunto(s)
Animales , Heparina/farmacología , Sitios de Unión , Bioensayo , Heparina/química , Peso Molecular , Estándares de Referencia , Ovinos/sangre , Relación Estructura-Actividad , Porcinos
9.
Rev Hosp Clin Fac Med Sao Paulo ; 46(2): 59-62, 1991.
Artículo en Portugués | MEDLINE | ID: mdl-1843369

RESUMEN

Heparin samples from four manufacturers and the First Argentinian Standard Heparin obtained from porcine mucosa were assayed by the Reinert and Winterstein method, modified as suggested by USP and Brazilian Pharmacopeias. Other methods described in the literature and their importance for the evaluation of anticoagulant activity of unfractionated heparins with low molecular weight are discussed.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Heparina/farmacología , Animales , Sitios de Unión , Bioensayo , Heparina/química , Peso Molecular , Estándares de Referencia , Ovinos , Relación Estructura-Actividad , Porcinos
11.
Urology ; 22(4): 432-4, 1983 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6636405

RESUMEN

We report the case of a five-year-old child who had a hard painless left testis discovered on a routine physical examination. He underwent a left inguinal orchiectomy, and the pathology examination revealed a dermoid cyst of the testis. This is a rare tumor, considering the low incidence of testicular tumors in childhood. Histologic criteria and surgical management are also presented. We believe this report is the first well-documented case.


Asunto(s)
Quiste Dermoide/patología , Neoplasias Testiculares/patología , Castración , Preescolar , Quiste Dermoide/cirugía , Humanos , Masculino , Neoplasias Testiculares/cirugía , Testículo/patología
12.
Science ; 206(4414): 55-7, 1979 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-17812450

RESUMEN

Throttling of freshwater inputs into the meromictic Dead Sea weakened the long-term stability of the water column. Between 1975 and 1978 successive deepenings of the pycnocline from 70 meters to beyond 200 meters were recorded. Complete overturn finally took place during the winter of 1978-1979. This unique process was accompanied by changes in the geochemistry of several components.

13.
Science ; 195(4273): 90, 1977 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-17796354
14.
Science ; 175(4024): 890-4, 1972 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-5008606

RESUMEN

The radioactive emanation product lead-212 is useful in estimating rates of air exchange within the urban boundary layer. The concentration of lead-212 is negligible in air of oceanic origin as well as in air above continental areas under snow cover. On several days when conditions were such that one of these types of air mass approached New York City, measurements were made which show that the source strength of lead-212 within the city is relatively constant. On two such days vertical profiles of the concentration of lead-212 were measured from the Empire State Building, which served as a sampling tower. From the data of these profiles and a two-layer model of the urban boundary layer, we estimate the vertical eddy diffusivity to be of the order of tens of square meters per second and the residence time of air within the street layer to be of the order of S minutes. These results are consistent with the observed distribution of stable lead and with an independent estimate of the eddy viscosity from a wind profile. Under moderate wind conditions and with a mixing depth of hundreds of meters, virtually all the horizontal transport of lead-212 and other tracers with street-level sources takes place in the advective layer.


Asunto(s)
Contaminación del Aire/análisis , Plomo/análisis , Radioisótopos/análisis , Movimientos del Aire , Polvo/análisis , Modelos Teóricos , Ciudad de Nueva York , Radón/análisis , Estaciones del Año , Factores de Tiempo , Tiempo (Meteorología)
15.
Science ; 159(3818): 977-9, 1968 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-5635995

RESUMEN

The concentrations of lead-212 and its short-lived daughter bismuth-212 in air near the ground were determined simultaneously by adaptation of the immersed-filter, delayed-coincidence technique of Assaf and Gat to measurement of the 3 x 10-(7)-second bismuth-212 and polonium-212 pair. The radioactive disequilibrium between lead-212 and bismuth-212 depends strongly on the efficiency of the ground in acting as a sink for these nuclides. This efficiency is low under dry conditions.


Asunto(s)
Contaminación Radiactiva del Aire , Bismuto/análisis , Radiación Cósmica , Plomo/análisis , Radiometría
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