Diabetes inducida por estreptozotocina y comportamiento de la barrera sanguínea del nervio óptico / Streptozotocin-induced diabetes, and the optic nerve blood barrier

OBJETIVOS: Conocer las características de la barrera sanguínea del nervio óptico de animales con diabetes inducida por estreptozotocina. MÉTODO: Los nervios ópticos de animales diabéticos y controles se estudiaron mediante microscopia óptica y microscopia electrónica de transmisión. La permeabilidad de los vasos fue determinada mediante la detección de albúmina con inmunofluorescencia indirecta y la expresión de las moléculas del complejo mayor de histocompatibilidad clase II mediante inmunofluorescencia directa. Asimismo, se realizó un análisis morfométrico de la superficie del nervio, el número de vasos y el engrosamiento de la célula endotelial y lámina basal. RESULTADOS: Los microvasos de los nervios ópticos de los animales diabéticos por efecto de la estreptozotocina se caracterizaron por un incremento en el grosor de su pared, conservación de los pericitos, incremento de la transcitosis en la célula endotelial y la presencia de una población importante de macrófagos perivasculares. En general, las manifestaciones del efecto de la hiperglucemia en el nervio óptico fueron más semejantes a las descritas para la microcirculación cerebral que a las descritas para la retina

OBJECTIVE: To study the features of the endoneurial micro-vessels of the optic nerve in streptozotocin-induced diabetic animals. METHODS: Optic nerves from control and streptozotocin-induced diabetic animals were studied by light and transmission electron microscopy. Patency was determined by indirect immunofluorescence albumin detection. The expression of major histocompatibility complex class II molecules was performed by direct immunofluorescence. The endoneurial vessels were counted, and the endothelial cell, the basement membrane, and the surface of the transverse section of the nerve were measured. RESULTS: Vessels of diabetic rats showed vessel wall thickening, preservation of pericytes, an increase in endothelial cell transcytosis, and an increased number of perivascular macrophage cells. It may be concluded that the effects of hyperglycaemia on the inner vessels of the optic nerve are more similar to the cerebral diabetic vessels than to the retinal vessels in diabetic animals

Streptozotocin-induced diabetes, and the optic nerve blood barrier.

OBJECTIVE: To study the features of the endoneurial micro-vessels of the optic nerve in streptozotocin-induced diabetic animals. METHODS: Optic nerves from control and streptozotocin-induced diabetic animals were studied by light and transmission electron microscopy. Patency was determined by indirect immunofluorescence albumin detection. The expression of major histocompatibility complex class II molecules was performed by direct immunofluorescence. The endoneurial vessels were counted, and the endothelial cell, the basement membrane, and the surface of the transverse section of the nerve were measured. RESULTS: Vessels of diabetic rats showed vessel wall thickening, preservation of pericytes, an increase in endothelial cell transcytosis, and an increased number of perivascular macrophage cells. It may be concluded that the effects of hyperglycaemia on the inner vessels of the optic nerve are more similar to the cerebral diabetic vessels than to the retinal vessels in diabetic animals.

[Diarrhoea in the traveller]. / Diarrea del viajero.

Diarrhoeic diseases caused by water and food contaminated by enteropathogens continue to be an important cause of morbidity in countries with a low level of development. Some 50,000 cases of diarrhoea in travellers are estimated in the world every day, and this is the main cause of consultation by travellers who return from undeveloped zones. The principal determinant of risk is the place of destination; there are significant differences between different regions with respect to risk and to the aetiology of the diarrhoea. The most frequent cause of diarrhoeas is of bacterial origin, which represents between 60 and 85% of the cases, while parasites represent 10% and some 5% are produced by viruses. Although it normally follows a benign course, complications can arise, with mortality being only exceptionally associated to this disease. Prevention is essentially based on strictly following elemental hygienic measures and avoiding the ingestion of foodstuffs and drinks with a risk of contamination. Prophylaxis with antibiotics is only advisable in journeys of short duration, in which the risk and/or seriousness of diarrhoeas, above all in immunosuppressed patients, are higher than the possible collateral effects. The treatment of diarrhoea in the traveller is based on adequate hydration, and the use of microbians is reserved for moderate and serious situations, with quinolones being the drug of choice. Rifaximine is a new drug approved for the treatment of diarrhoeas in the traveller, above all in areas with enteropathogens that are resistant to quinolones.

Diarrea del viajero / Diarrhoea in the traveller

Las enfermedades diarreicas causadas por la contaminación de agua y alimentos por enteropatógenos continúan siendo causa de importante morbilidad en los países con escaso nivel de desarrollo. Se estima alrededor de unos 50.000 casos diarios de diarreas del viajero en el mundo, siendo el principal motivo de consulta de los viajeros que regresan de zonas no desarrolladas. El principal determinante de riesgo es el lugar de destino, existiendo diferencias importantes entre las distintas regiones en cuanto al riesgo y la etiología de la diarrea. La causa más frecuente de diarreas es la bacteriana, que representa del 60 al 85% de los casos, los parásitos representan el 10% y un 5% están producidas por virus. Aunque habitualmente cursa de forma benigna, pueden aparecer complicaciones, siendo excepcional la mortalidad asociada esta enfermedad. La prevención se basa fundamentalmente en seguir estrictamente las medidas higiénicas elementales y evitar la ingesta de alimentos y bebidas con riesgo de contaminación. La profilaxis con antibióticos sólo se aconseja en viajes de corta duración, en los que el riesgo y/o gravedad de las diarreas, sobre todo en pacientes inmunosuprimidos, sean superiores a los posibles efectos colaterales. El tratamiento de la diarrea del viajero se basa en una adecuada hidratación y se reserva el uso de antimicrobianos para situaciones clínicas moderadas y graves, siendo las quinolonas el fármaco de elección. La rifaximina es un nuevo fármaco aprobado para el tratamiento de las diarreas del viajero, sobre todo en áreas con enteropatógenos resistentes a las quinolonas

Diarrhoeic diseases caused by water and food contaminated by enteropathogens continue to be an important cause of morbidity in countries with a low level of development. Some 50,000 cases of diarrhoea in travellers are estimated in the world every day, and this is the main cause of consultation by travellers who return from undeveloped zones. The principal determinant of risk is the place of destination; there are significant differences between different regions with respect to risk and to the aetiology of the diarrhoea. The most frequent cause of diarrhoeas is of bacterial origin, which represents between 60 and 85% of the cases, while parasites represent 10% and some 5% are produced by viruses. Although it normally follows a benign course, complications can arise, with mortality being only exceptionally associated to this disease. Prevention is essentially based on strictly following elemental hygienic measures and avoiding the ingestion of foodstuffs and drinks with a risk of contamination. Prophylaxis with antibiotics is only advisable in journeys of short duration, in which the risk and/or seriousness of diarrhoeas, above all in immunosuppressed patients, are higher than the possible collateral effects. The treatment of diarrhoea in the traveller is based on adequate hydration, and the use of microbians is reserved for moderate and serious situations, with quinolones being the drug of choice. Rifaximine is a new drug approved for the treatment of diarrhoeas in the traveller, above all in areas with enteropathogens that are resistant to quinolones

Granuloma maligno medio facial / Medial facial malignant granuloma

Ingresó en el Servicio de O.R.L. del Hospital Provincial Universitario Camilo Cienfuegos una paciente femenina R.O.R. de raza negra, de 51 años de edad, por presentar lesiones en la orofaringe y síndrome general, que al examinársele la orofaringe se aprecia lesión ulcerada del pilar anterior y posterior de la amígdala derecha, úlcera que se extiende al pilar anterior y posterior de la amígdala izquierda, con fondo limpio, bordes rosados, tejido friable y fetidez intensa. Remiten las lesiones posteriores al uso de esteroides y es egresada con tomas de biopsias con células inflamatorias. Reingresa dos meses después con desaparición anatómica de la orofaringe, úvula amputada, ausencia de ambos pilares. Fallece en shock hipovolémico por epistaxis severa, diagnosticándosele días antes Granuloma maligno medio facial por L.N.H. de alto grado de malignidad(AU)

A 51 year-old black female patient (R:O:R) was admitted at the otolaringology service of the Camilo Cienfuegos University Hospital for presenting lesions in the oropharynx and general syndrome. On exam, an ulcerated lesion of the anterior and posterior pillars of the right tonsil is observed that extends to the anterior and posterior pillar of the left tonsil, with a clean bottom, rosy borders, friable tissue and intense fetidity. Steroids are prescribed to remit the posterior lesions and she is discharged with takings of biopsies with inflammatory cells. She is readmitted two months later with an anatomical disappearance of the oropharynx, amputated uvula, and absence of both pillars. She dies in hypovolemic shock from severe epistaxis, with a diagnosis being made of medial facial malignant granuloma from L.N.H. of a high degree of malignancy some days before(AU)

Purple membrane-polyacrilamide films as holographic recording materials.

The holographic parameters of purple membrane-polyacrylamide films obtained from a mutant form of Halobacterium salinarum (originally Halobacterium halobium) were measured. The synthesized films have an absorption of around 2.5 at 532 nm and a pH of 8.65. The results show that diffraction efficiencies of about 1.2 % (measured at 633 nm) can be achieved with writing intensities in the range of 200-400 mW/cm2 (532 nm), and these values remain constant after saturation. Pump-probe experiments were also used to measure the M state lifetime and our PM films were found to have the lowest M state lifetime described at this pH.

Chromatographic removal combined with heat, acid and chaotropic inactivation of four model viruses.

The virus removal of protein A affinity chromatography, inactivation capacity, acid pH and a combination of high temperature with a chaotropic agent was determined in this work. The model viruses studied were sendaivirus, human immunodeficency virus (HIV-IIIb), human poliovirus type-II, human herpesvirus I and canine parvovirus. The protein A affinity chromatography showed a maximum reduction factor of 8 logs in the case of viruses larger than 120 nm size, while for small viruses (18-30 nm) the maximum reduction factor was about 5 logs. Non viral inactivation was observed during the monoclonal antibody elution step. Low pH treatment showed a maximum inactivation factor of 7.1 logs for enveloped viruses. However, a weak inactivation factor (3.4 logs) was obtained for DNA nonenveloped viruses. The combination of high temperature with 3 M KSCN showed a high inactivation factor for all of the viruses studied. The total clearance factor was 23.1, 15.1, 13.6, 20.0 and 16.0 logs for sendaivirus, HIV-IIIb, human poliovirus type-II, human herpesvirus I and canine parvovirus, respectively.

Prognostic significance of Ki-67 nuclear proliferative antigen, bcl-2 protein, and p53 expression in follicular and diffuse large B-cell lymphoma.

We analyzed 104 patients with non-Hodgkin's lymphoma, follicular or diffuse large-B-cell-type lymphoma, in order to evaluate the correlation between clinical characteristics and immunohistochemical parameters. Immunostaining was performed by means of monoclonal antibodies against Ki-67, bcl-2, and p53 expression. Forty-nine of the patients showed follicular lymphoma. A high expression of bcl-2 was found in 93%, high expression of p53 in 57%, and low expression of Ki-67 in 96%. Follicular lymphoma grade III showed a p53 expression (p = 0.07) slightly higher than follicular lymphoma grades I and II, not reaching statistical significance. Follicular lymphoma grades I and II tended to express lower Ki-67 and higher levels of bcl-2 expression than grade III (p = 0.06). Fifty-five cases showed diffuse large-B-cell lymphoma. Among them, bcl-2 was absent in 39%, whereas p53 and Ki-67 expression were high in 38%. In the diffuse large-B-cell lymphomas, a high bcl-2 expression correlated with stages III and IV (p = 0.03) and involvement of more than one extranodal area (p = 0.03). High Ki-67 expression was also associated to extranodal involvement of more than one area (p = 0.03). Overall survival of patients did not show statistically significant differences regarding Ki-67, bcl-2, and p53 tumoral expression. Prognostic factors for overall survival in the multivariate analysis were age (p = 0.02) and LDH (p = 0.003). Time to progression was worse among follicular lymphoma with high p53 expression than with mild/moderate p53 expression (p = 0.009).

Non-viral gene delivery: vehicle and delivery characterization.

The development of non-viral gene therapy has been hampered by an inability to reproducibly manufacture and characterize delivery system components and final formulations. Formation of interpolyelectrolyte complexes as the basis of various gene delivery methods has been approached as the first step towards development of synthetic viruses. We have found that preparation of interpolyelectrolyte complexes from disperse reagents gives a more homogeneous gene delivery vehicle than other methods. Methods which increase homogeneity also result in higher transfection efficiency in vivo. Expression levels of human growth hormone and other reporter proteins in mice confirm the potential of parenteral non-viral gene delivery for some therapeutic applications. Serum is demonstrated to inhibit transfection efficiency in vivo. Our results suggest that further development of methods to manufacture homogeneous disperse non-viral delivery vehicles with stealth characteristics may enhance both the potency and reproducibility of gene transfer in vivo.

Vigilancia epidemiológica de las infecciones intrahospitalarias: estudios sistematizados de prevalencia (1993-1994) / Epidemiological surveillance in intrahospital infections: systemic studies of prevalence (1993-1994)

A partir de la sistematización de los estudios de prevalencia en 1993, continuamos con la presentación de los datos obtenidos en 1994, en conjunto con los del peíodo anterior. Esto permite tener una visualización gráfica de los resultados obtenidos pudiéndose analizar así sus tendencias. Si bien la metodología básica de los estudios no se ha modificado, a partir de diciembre de 1993 se incorporó al análisis, un sistema subjetivo que permite estratificar el nivel de gravedad de los pacientes y relacionarlo con el riesgo de infección intrahospitalaria. Este modelo fue validado a partir de los estudios de diciembre de 1993, abril y agosto de 1994, evaluándose además su reproducibilidad. El análisis comparativo de los estudios de prevalencia, muestra la persistencia de una proporción elevada de pacientes con acceso vascular (>50 por ciento) y catéter urinario (>20 por ciento), lo que determina un riesgo incrementado de desarrollar infecciones asociadas a estos factores. La tasa de prevalencia de infecciones intrahospitalarias se mantuvo por encima del 10 por ciento...(AU)

Vigilancia epidemiológica de las infecciones intrahospitalarias: estudios sistematizados de prevalencia (1993-1994) / Epidemiological surveillance in intrahospital infections: systemic studies of prevalence (1993-1994)

A partir de la sistematización de los estudios de prevalencia en 1993, continuamos con la presentación de los datos obtenidos en 1994, en conjunto con los del peíodo anterior. Esto permite tener una visualización gráfica de los resultados obtenidos pudiéndose analizar así sus tendencias. Si bien la metodología básica de los estudios no se ha modificado, a partir de diciembre de 1993 se incorporó al análisis, un sistema subjetivo que permite estratificar el nivel de gravedad de los pacientes y relacionarlo con el riesgo de infección intrahospitalaria. Este modelo fue validado a partir de los estudios de diciembre de 1993, abril y agosto de 1994, evaluándose además su reproducibilidad. El análisis comparativo de los estudios de prevalencia, muestra la persistencia de una proporción elevada de pacientes con acceso vascular (>50 por ciento) y catéter urinario (>20 por ciento), lo que determina un riesgo incrementado de desarrollar infecciones asociadas a estos factores. La tasa de prevalencia de infecciones intrahospitalarias se mantuvo por encima del 10 por ciento...

[The molecular diagnosis of hereditary diseases. In memoriam Dr. Eduardo Aguirre Pequeño]. / Diagnóstico molecular de enfermedades hereditarias. En memoria del académico doctor Eduardo Aguirre Pequeño.

Accordingly, we have established in our unit a DNA diagnosis laboratory and have started molecular genetics and epidemiological studies of several inherited diseases. We have started with cystic fibrosis, muscular dystrophy and hemophilia A. We practice the molecular diagnosis with both, Southern transfer and the polymerase chain reaction, using either direct (detection of mutations) or indirect (restriction fragment length polymorphisms) approaches. With the studies we have so far carried out, we have been able to provide genetic counseling and gained valuable information on the type and frequency of mutation associated to these diseases in our region.

[The molecular genetics of cystic fibrosis: the delta F508 allele in Mexican families]. / Genética molecular de la fibrosis quistica: el alelo delta F508 en familias mexicanas.

We have initiated the screening of the delta F508 cystic fibrosis (CF) mutation in our country basing our study on the polymerase chain reaction technique. In a sample of 10 western and a northeastern Mexican families that have at least one CF affected child, we found a delta F508 frequency of 59.1% among CF chromosomes. This frequency is similar to those reported for Spain. Furthermore, we found a correlation between the delta F508 allele and pancreatic insufficiency. This paper points out the advantage of the polymerase chain reaction technology for the analysis of Mendelian disorders.