Tomografía de Coherencia Óptica. Uso en Dermatología / Optical Coherence Tomography. Use in Dermatology

RESUMEN La Tomografía de Coherencia Óptica (OCT) ha sido recientemente muy usada en diversas patologías de piel. Es una técnica no invasiva para la investigación morfológica de los tejidos, comparable con una biopsia virtual, capaz de generar imágenes en sección transversal de la microestructura del tejido; esta técnica se basa principalmente en el esparcimiento de la luz en los medios a estudiar y gracias a las fibras de colágeno hace que pueda utilizarse en la piel. Con el uso de OCT, es posible caracterizar la morfología normal y patológica de la piel, similar a la arquitectura del tejido que se observa en la histología de rutina, así como la progresión de la enfermedad, la cual se puede investigar in situ. Representa un enfoque no traumático y eficiente en el tiempo para el diagnóstico y seguimiento de un amplio número de enfermedades dermatológicas.

SUMMARY The Optical Coherence Tomography (OCT) has recently been widely used in various skin pathologies. It is a non-invasive technique for the morphological research of tissues, comparable with a virtual biopsy, capable of generating cross-sectional images of the tissue microstructure; this technique is based mainly on the scattering of light in the media to be studied and thanks to the collagen fibers it can be used on the skin. With the use of OTC, it is possible to characterize the normal and pathological morphology of the skin, similar to the tissue architecture observed in routine histology, as well as the progression of the disease which can be investigated in situ. Representing a non-traumatic and time-efficient approach for the diagnosis and monitoring of a large number of dermatological diseases.

Potential Applications of Silk Fibroin as Vascular Implants: A Review.

Cardiovascular disease is a worldwide main cause of morbidity and mortality. Treatment alternatives include the use of cardiovascular implants that have generated a constant search for materials, and transformation processes that provide structures similar to those that need to be replaced. Among the biomaterials available for vascular implants, silk fibroin (SF) is of great interest because it is a natural, biodegradable, biocompatible protein. In addition, SF has outstanding mechanical properties and can be easily processed by various techniques. This article presents a general review of SF, its potential use as a biomaterial for vascular applications, and modifications that improve its hemocompatibility.

La lente dermatológica… historia y algo más / Dermatological vision lens... history and something else

El microscopio es un instrumento, que desde hace muchos años es herramienta diagnóstica en Dermatología. La evolución del microscopio ha ido en sinergia con el avance de la tecnología, siendo el desarrollo de imágenes microscópicas digitalizadas, fuente de estudio en la época actual. El uso de estas imágenes en Dermatología ha permitido realizar diagnósticos en tiempo real; situación que vence la celeridad diagnóstica y aminora tanto para el médico como para el paciente, la lentitud de otras técnicas. El conocimiento sobre los diferentes métodos que se utilizan actualmente, para confirmar diagnósticos de enfermedades cutáneas, como: la dermatoscopía, la dermatoscopía multiespectral y la microscopía confocal de reflectancia, son imprescindibles para la formación del dermatólogo de hoy en día, ya que, con ellos se resumen pasos para el manejo definitivo de los pacientes. Con esta disertación, realizaremos un breve análisis de la historia de la microscopía, desde sus inicios hasta la era digital y los beneficios que se obtienen, con el uso de cada una de estas técnicas diagnósticas.

The microscope, is an instrument that for many years is used as a diagnostic tool in Dermatology. The evolution of the microscope has gone in synergy with the advancement of technology, being the development of digitized microscopic images a source of study and research in the present time. The use of these images in Dermatology has carried out diagnoses in real time; situation that overcomes the diagnostic speed and reduces for both the doctor and the patient the slowness of other techniques. The knowledge about the different methods currently used to confirm skin diseases, such as dermatoscopy, multispectral dermoscopy and confocal reflectance microscopy, is essential for the formation of today's dermatologist, since they summarize the steps for the definitive management of patients. With this dissertation, we will make a brief analysis of the history of microscopy from its beginnings to the digital age, and the benefits obtained with the use of each of these diagnostic techniques.

Morfea localizada en cuero cabelludo / Localized morphea on the scalp

La morfea o esclerodermia localizada, es una enfermedad del tejido conectivo, benigna, crónica y autoinmune, que se caracteriza por un endurecimiento de la piel, debido a una síntesis aumentada de colágeno. La incidencia anual varía entre 0,4 y 2,7 por 100.000 personas, con un predominio femenino de 2,4 a 4,2:1 y es dos a tres veces más frecuente que la esclerosis sistémica. Existen diversas formas de presentación, siendo la morfea en placas la más común en los adultos y la afectación del cuero cabelludo, en niños. El diagnóstico es clínico y se confirma mediante biopsia.

Morphea or localized scleroderma, is a benign, chronic, and autoimmune connective tissue disease, characterized by a hardening of the skin, due to an increased synthesis of collagen. The annual incidence varies from 0.4 to 2.7 per 100.000 people, with a female predominance of 2.4 to 4.2: 1 and is two to three times more frequent than systemic sclerosis. There are several forms of presentation, with plaque morphea being the most common in adults and the scalp involvement, in children. The diagnosis is clinical and confirmed by biopsy.

Paradojas del color en dermatología / Paradoxes of color in dermatology

La lógica dermatológica, ha encontrado el rompimiento de los paradigmas semiológicos, desde la incorporación de la imagen digital al estudio de las lesiones de piel, características como: forma, límites, contraste, estructura y profundidad están ligadas al color. Su percepción puede objetivarse, con la ayuda de instrumentos como el dermato-colorímetro, el derma-espectrofotómetro e inclusive el dermatoscopio digital, que permiten corregir los errores de metamerismo. En esta disertación pretendemos abrir nuevas ideas, sobre la importancia de estudiar el color de la piel más allá del fototipo cutáneo, así como, reconocer el color estructurado como una variante de la semiología pigmentaria y la incorporación del estudio heurístico, en el diseño de modelos enseñanza-aprendizaje para los programas de Dermatología.

The dermatological logic study has found breaking out paradigms since the introduction of digital imaging for the study of skin disease, features like shape, boundaries, contrast, depth and structure are related to color, color perception can be objectified through instruments such as derm-colorimeter, derm-spectrophotometer and even digital dermatoscopy, which can correct the metamerism phenomenon. In this dissertation, we intend to open mind and give new ideas about the importance of studying the skin color beyond the skin phototype, recognize the structured color as a variant of the semiology of color, as well as the incorporation of models of study design teaching-learning heuristic for dermatology programs.

Evolution of HIV incubation times in AIDS patients.

Since introduction of highly active antiretroviral therapy (HAART), the incidence of AIDS has gradually declined, although the incidence of HIV infection is largely unknown. We have studied a sample with 10,571 patients whose data were recorded by Spain's public health system, in the Andalusian Register of Cases of AIDS. The diagnoses correspond to the period January 1981 to June 2008. For this period, AIDS incubation times were analyzed by means of the survival and risk functions, using R survival and DTDA libraries. We have studied the evolution of incubation mean times according to specific variables from database. The obtained results show that the mean times of viral incubation presented a growing trend that was greater among women when the study was limited to heterosexual transmission. Stratifying by category of transmission, the longest incubation period was seen for intravenous drug users (IDU). Both gender and IDU transmission were associated with significantly greater survival without AIDS. In contrast, heterosexual transmission or pneumonia diagnosis were associated with lower survival without AIDS.

Interaction of zinc or vitamin A supplementation and specific parasite infections on Mexican infants' growth: a randomized clinical trial.

BACKGROUND: The efficacy of micronutrient supplementation on growth may be modified by specific gastrointestinal parasite infections. METHODS: We carried out a double-blind placebo-controlled trial to evaluate the effect of vitamin A and zinc supplementation on gastro-intestinal pathogen infections and growth among 584 infants in Mexico City. Children aged 5-15 months were assigned to receive either a vitamin A supplement every 2 months (20,000 IU of retinol for infants < or =; 1 year or 45,000 IU for infants >1 year), a daily supplement of 20 mg of zinc, a combined vitamin A-zinc supplement or a placebo, and were followed up for 1 year. Weight and length were measured once a month and morbidity histories were recorded twice a week for 12 months. Monthly stool samples were screened for Giardia duodenalis, Ascaris lumbricoides and Entamoeba spp. Growth velocity slopes, generated from the linear regression of individual child length, and height-for-age z-scores on time were analyzed as end points in regression models, adjusting for the presence of parasite infections. RESULTS: The main effect of vitamin A supplementation was in height improvement (P<0.05), and was only found in the model evaluating infants with any parasite. There was an interaction effect of slower growth (P<0.05) found in infants infected with any parasite and supplemented with vitamin A in slower growth (P<0.05). In addition, the interaction of zinc supplementation and Giardia duodenalis or A. lumbricoides was associated with reduced growth (P<0.05). CONCLUSION: Gastro-intestinal parasite infections may modify the effect that zinc or vitamin A supplementation has on childhood growth.

[Pregnancy and delivery among adolescents under 15: a study of 181 cases in French Guiana]. / Grossesses et accouchement chez les adolescentes de moins de 15 ans: étude de 181 cas en Guyane française.

OBJECTIVE: The purpose of this study were to determine the effects and consequences of premature pregnancy and childbirth among adolescents under 15 years of age in French Guyana. MATERIAL AND METHODS: A retrospective field-case study between the 1(st) and the 31(st) December 2001 identified 181 births among adolescents aged 14 years and under. Comparisons were made with 181 births among 18-year-old first-time mothers taking place over the same period. RESULTS: 1.55% of all births in the maternity ward at St Laurent-du-Maroni Hospital involved adolescents under the age of 15. 24.6% of these young mothers were enrolled in secondary school, 21% were beneficiaries of the national social security health insurance and 61% of them were born outside Guyana. Pre-natal monitoring was less frequent among the group of teenage mothers, and preterm labor (0.04 < p < 0.05), anemia (0.02 < p < 0.03) and Chlamydiae trachomatis infections (0.03 < p < 0.04) are more frequent. There is no significant difference regarding high blood pressure, diabetes, or infectious diseases (except from Chlamydiae) or regarding labor and delivery. Mean birth weight was lower (p = 0.01) and the Apgar score was more often less than 7 at the first minute (p < 0.05) among newborn of teenage mothers. CONCLUSION: While pregnancies among younger teenagers appear to indicate a higher level of associated medical problems, a more thorough pre-natal check-up program would certainly reduce the number of problem related cases. The extremely high proportion of teenage pregnancies in the West of French Guiana has become a major public health issue for the entire region.

[Severe maternal anemia and pregnancy outcome]. / Anémies maternelles sévères et issues de grossesse.

OBJECTIVES: The aim of this study was to determine the effects of severe antenatal maternal anemia on pregnancy outcome. MATERIAL: and methods. A retrospective study comparing 2 groups of pregnant women: 111 (pregnant women) with anemia (Hb < 8 g/dl), 111 non- anemic pregnant women (Hb >10 g/dl). Clinical and biological characteristics for both groups were compared. Data on the newborn babies were collected. RESULTS: In the anemic group: iron deficiency was the most common cause of anemia (92.7%). There was no significant difference between the 2 groups with respect to age or parity. Maternal anemia was found to be significantly associated with more frequent preterm birth (29.2% vs 9.2%) and increased low birth weight (2933 g vs 3159 g). DISCUSSION: The literature is not conclusive on the influence of anemia in pregnant women. More frequent preterm birth and low birth weight have been reported in the majority of studies considering mild to moderate maternal anemia (in contrast to our study where the mothers had severe anemia). Many studies indicated that routine iron supplementation during pregnancy may have beneficial effects on pregnancy outcome. Severe anemia in pregnancy may have adverse effects for the newborn and should be treated or prevented early in pregnancy.

[Medical termination of pregnancy at 9-14 weeks gestation. Prospective study of 105 cases in Saint-Laurent-du-Maroni (French Guyana)]. / L'interruption volontaire de grossesse médicamenteuse de 9 à 14 semaines d'aménorrhée: étude prospective de 105 cas à Saint-Laurent-du-Maroni (Guyane française).

OBJECTIVES: To demonstrate the effectiveness and safety of mifepristone 600mg with misoprostol 800 mg, for termination of pregnancy at 9-14 weeks gestation. PATIENTS AND METHODS: This prospective study included 105 women at 9 to 14 weeks gestation given 800 mg of vaginal misoprostol, 2 or 3 days after a single dose of 600 mg of mifepristone for pregnancy termination. Outcomes measures included mean expulsion time, the interval between fotal and placental expulsion, adverse effects, vaginal bleeding, requirement for analgesia, and hospital stay, analyzed by parity and gestational age. RESULTS: Pregnancy termination was successful in 92.4% of the patients without requirement for surgery. The mean time to expulsion was 6 hours. The fetus and placenta were expelled together in 79% of the cases. In 15% the conception products were retained in the cervical canal, and removed with a ring forceps. Additional misoprostol doses were necessary in 33% and analgesia (nalbuphine sublingually, mean dose was 10mg) in 56%. Significant bleeding was observed in 7.5%, leading to curettage in 2 patients. No statistically significant differences were found between the rate of success and term (9-12 versus 12-14) or parity. CONCLUSION: Combining oral mifepristone and vaginal misoprostol is a successful alternative to surgical termination of pregnancy, even after 9 weeks' gestation. The use of nalbuphine for analgesia improves acceptability; sublingual administration helps avoid invasive procedures. Before 14 weeks gestation, the legal limit for termination of pregnancy in France, the choice between the surgical and medical alternatives should be left to the patient.

[Typhoid fever and pregnancy]. / Fièvre typhoïde et grossesse.

Typhoid fever is rare in Europe, but well-recognized endemic disease in tropical zones. We report our findings in a series of 25 cases of typhoid fever during pregnancy observed in French Guiana and reviewed the literature on clinical signs, diagnosis and treatment. Salmonellea typhi causes septicemia of digestive origin that can cross the placenta resulting in chorioamniotitis. Maternal-fetal infection with S. typhi can lead to miscarriage, fetal death, neonatal infection, as well as diverse maternal complications. In order to avoid maternal complications and possible fetal transmission, treatment with ceftriaxone should be initiated as early as possible

Genes coding structural proteins in the Leishmania braziliensis complex.

Acidic ribosomal P1 and P2b proteins, referred to as P proteins, and histone H3 are reported for first time in the Leishmania braziliensis complex. Deoxyribonucleic acid analysis and multiple sequence alignment suggest that both P proteins may maintain their structural function in the ribosomal stalk, in spite of the high rate of mutations detected. The deduced amino acid sequence of protein P1 showed 51% identity with Trypanosoma cruzi protein P1 and protein P2b showed 61% identity with T. cruzi protein P2b. Another conserved protein, L. (Viannia) braziliensis histone H3, showed 82% and 70% identity with histone H3 of L. (Leishmania) infantum and T. cruzi, respectively. The N-terminal end of this histone is divergent in comparison with the consensus eukaryotic sequence. Their predicted tridimensional structure was designed.

Acidic ribosomal proteins and histone H3 from Leishmania present a high rate of divergence.

Another additional peculiarity in Leishmania will be discussed about of the amino acid divergence rate of three structural proteins: acidic ribosomal P1 and P2b proteins, and histone H3 by using multiple sequence alignment and dendrograms. These structural proteins present a high rate of divergence regarding to their homologous protein in Trypanosoma cruzi. At this regard, L. (V.) peruviana P1 and T. cruzi P1 showed 57.4% of divergence rate. Likewise, L. (V.) braziliensis histone H3 and acidic ribosomal P2 protein exhibited 31.8% and 41.7% respectively of rate of divergence in comparison with their homologous in T. cruzi.

Diagnóstico temprano del virus dengue 1 usando RT-PCR y perspectivas para la caracterización molecular de cepas autóctonas / Early Diagnosis of Dengue 1 virus used RT-PCR and perspectives for the molecular caracterization of autoctons strains

Un sistema de diagnóstico para la detección temprana del virus Dengue 1 fue llevado a cabo exitosamente usando la reacción en cadena por polimerasa de trnscriptasa reversa (RT-PCR), a través de la amplificación de una porción genómica del gen NS1. Los resultados obtenidos, a partir de muestras clínicas, corroboraron los datos de anteriores trabajos de RT-PCR dirigidos hacia la región estructural del virión. POsteriormente el ADNc del virus Dengue, correpondiente a una de las muestras serológicas, fue clonado y secuenciado. La comparación por ánalisis de secuencia nucleotídica con otras cepas referenciales determino que la cepa viral correspondía al serotipo 1

Detección de Bartonella bacilliformis usando PCR-RFLP / Detection of Bartonella bacilliformis using PCR-RFLP

Reportamos la aplicación de las técnicas moleculares PCR-RFLP para la confirmación de infecciones por Bartonella bacilliformis. El método de PCR-RFLP se basa en la amplificación in vitro de un fragmento de 380 pb correspondiente al gen citrato sintetasa a partir de sangre y cultivos in vitro. El análisis del producto de amplificación por cortes con las enzimas restricción Hinfl y Taql permite caracterizar molecularmente que el brote ocurrido en Urubamba, Cuzo fue producido por Bartonella bacilloformis. Este método es aplicado directamente a sangre y a cultivos

Recombinant antigens for specific and sensitive serodiagnosis of Latin American tegumentary leishmaniasis.

The diagnostic potential of recombinant leishmanial antigens for Latin American tegumentary leishmaniasis (LATL) was examined. Two Leishmania (Viannia) peruviana recombinant proteins, T26-U2 and T26-U4, were assessed by their reactivity to detect specific anti-leishmanial antibodies. Seventy-eight individual sera from persons with LATL, 39 from those with other diseases, and 10 negative control sera were tested by Western blotting and enzyme-linked immunosorbent assay. The sensitivity of the test using T26-U2 plus T26-U4 was similar to that obtained with whole parasite extract (92%). However, the specificity obtained using both recombinant antigens (87%) was higher than that of the whole parasite extract (65%). All tests using recombinant proteins (T26-U2, T26-U2 plus T26-U4 or T26-U4) had a higher positive predictive value (89%, 92% and 98%, respectively) than the value obtained using total parasites (81%). Eleven Colombian sera were also tested, and the results indicated that T26-U2 plus T26-U4 could be used successfully in Peru and in other Latin American countries.

[Urban-rural variations in medical care of children with diarrhea in Mexico]. / Variaciones urbano-rurales en la atención del niño con enfermedad diarreica en México.

OBJECTIVE: To study the urban and rural variations of medical care for acute diarrhea among children under five years old. MATERIAL AND METHODS: Data from the 1993 Effective Household Treatment National Survey were analyzed. A number of 338 children from urban areas and 300 from rural areas were included in the study. Variables included were: household treatment, health-seeking behavior, mothers' previous training to manage acute diarrhea, use of oral rehydration salts (ORS) and availability of and access to health care. RESULTS: Oral rehydration therapy (ORT) as part of the household treatment and feeding the regular diet were more frequently found in rural areas. Less than 50% of children received medical care in both settings. In urban areas most children were cared for by private physicians. About 30% of children needed medical care but they were not taken to medical facilities. Physicians in rural areas prescribed ORS more frequently, while those from urban areas prescribed medication and restrictive diets in a greater proportion. Physicians working in public facilities prescribed ORT in greater proportions than private ones. Mothers from rural areas had received more training to manage diarrhea but they had restricted access to medical care in comparison to mothers from urban areas. CONCLUSIONS: It is necessary to improve health care education of urban populations, to increase access and coverage of health services in rural areas and to strength activities to improve the quality of medical care provided by private physicians and by those working in urban areas.

Antenatal diagnosis of upper urinary tract dilation by ultrasonography.

The criteria for the detection of fetal pyelectasis are still controversial. Prenatal and postnatal data from 2,170 consecutive pregnant women who underwent at least one antenatal ultrasound scan were prospectively studied. Fetal pyelectasis was defined on the basis of a mean renal pelvis dimension > 5 or 10 mm before or after 28 weeks of gestation, respectively. Pyelectasis was detected in 95 (4.4%) fetuses. Eighty-nine among them were explored after birth. In 13 (13.7%) cases, an obstructive urinary tract abnormality, a severe vesicoureteral reflux, or a megaureter were diagnosed postnatally. In 29 (30.5%) cases, pyelectasis was confirmed postnatally, while complementary investigations ruled out an obstruction of the urinary tract. The incidence of urinary tract malformations was thus 0.60%, while the positive predictive value was 13.7%. We recommend to use a value not < 10 mm of the renal pelvis mean dimension beyond 28 weeks of gestation as a threshold for detection of fetal upper urinary tract obstruction, in the absence of ureteric and/or bladder dilation. Any value between 5 and 10 mm measured during the 2nd trimester of gestation should be confirmed by a second ultrasound examination performed during the 3rd trimester, before being considered pathological.

Aplasia cutis congenita of the scalp with large underlying skull defect: a case report.

Localised agenesis of the scalp is the most frequent pattern in aplasia cutis congenita (ACC), a congenital absence of the skin and occasionally of deeper layers. Several clinical groups are characterised by the location and pattern of skin defects, associated malformations and the mode of inheritance. Death occurs in 20% of cases, secondary to the associated anomalies, to infections or to haemorrhage from ulceration of the sagittal sinus when there is also a defect of the underlying skull. In this latter case, we close the defect by two rotational scalp flaps (Orticochea technique) at birth. A three-dimensional CT study is useful for showing the extent of the skull defect and the deformity of the craniofacial complex and the changes in the bone after treatment.