Optimization of digital image processing to determine quantum dots' height and density from atomic force microscopy.

An optimized method of digital image processing to interpret quantum dots' height measurements obtained by atomic force microscopy is presented. The method was developed by combining well-known digital image processing techniques and particle recognition algorithms. The properties of quantum dot structures strongly depend on dots' height, among other features. Determination of their height is sensitive to small variations in their digital image processing parameters, which can generate misleading results. Comparing the results obtained with two image processing techniques - a conventional method and the new method proposed herein - with the data obtained by determining the height of quantum dots one by one within a fixed area, showed that the optimized method leads to more accurate results. Moreover, the log-normal distribution, which is often used to represent natural processes, shows a better fit to the quantum dots' height histogram obtained with the proposed method. Finally, the quantum dots' height obtained were used to calculate the predicted photoluminescence peak energies which were compared with the experimental data. Again, a better match was observed when using the proposed method to evaluate the quantum dots' height.

Modelación y simulación de la arteria aorta a partir de datos clínicos utilizando un modelo fraccional viscoelástico y el método del elemento finito / Modeling and simulation of the aorta from clinical data using a fractional viscoelastic model and finite element method

Los modelos y simulaciones de los efectos biomecánicos presentes en la arteria aorta, le proporcionan al especialista de la salud una herramienta computacional, que puede ser empleada en la prevención y el tratamiento de las enfermedades cardiovasculares. Es por esto que en la presente investigación se desarrolla un modelo matemático con la finalidad de implementarlo en simulaciones tridimensionales digitales que permitan analizar el comportamiento mecánico de arterias. Primero se describe la metodología utilizada en la construcción de la geometría de la arteria basada en imágenes provenientes de una tomografía axial computarizada, los ensayos experimentales necesarios para la obtención de los parámetros mecánicos requeridos por el modelo y por último su orden fraccional. Con lo que se obtiene una simulación mediante elementos finitos donde se identifican las zonas de mayor concentración de esfuerzos y el campo de desplazamientos. Para poder obtener estos resultados se empleó una formulación novedosa basada en modelos viscoelásticos de orden fraccional donde además se obtuvieron, a través del módulo complejo, los valores requeridos para la simulación.

The modeling and simulation of the biomechanical effects present in the aorta, give the health specialist a computational tool that can be used in the prevention and treatment of cardiovascular diseases. For that reason on this research a mathematical model was developed in order to implement digital dimensional simulations to analyze the mechanical behavior of arteries. First, its described the methodology used in the construction of the geometry of the artery based on images from a CT scan, next the necessary experimental tests to obtain mechanical parameters required by the model and finally his fractional order. Obtaining a finite element simulation where the areas of greatest stress concentration and the displacement field are identified. To obtain these results a novel formulation based on fractional order viscoelastic models was used and the values required for simulation were obtained through the complex modulus.

Determinación de la Rigidez Arterial Empleando Simulación Computacional / Determination of Arterial Stiffness Using Computational Simulation

El incremento de la rigidez arterial está asociado con el desarrollo de enfermedades cardiovasculares, las cuales constituyen una de las principales causas de muertes en el mundo. Por este motivo el desarrollo de métodos no invasivos que permitan cuantificar la rigidez arterial ha alcanzado un gran impacto. En este trabajo se estudia el método no invasivo de medición de la velocidad de la onda del pulso de la arteria braquial al tobillo (baPWV), por sus siglas en inglés. Para estudiar este método se simularon las formas de ondas de presión en el sistema arterial empleando un modelo unidimensional, a partir de las cuales se determinaron los valores de baPWV. Estos valores fueron comparados con los calculados por otros dos métodos: cfPWV (velocidad de la onda del pulso entre la carótida y la femoral, el método estándar) y PWVteor (ecuación de Bramwell-Hill), obteniéndose correlaciones significativas, r=0.967 y r=0.9828 respectivamente. Se investigó la sensibilidad del método baPWV a la variación de la rigidez, representada por la variación de la distensibilidad y, se concluyó que el método es sensible a los cambios de rigidez que ocurren tanto en las arterias centrales como en las arterias periféricas.

The arterial stiffness increased is associated with the development of cardiovascular diseases, which constitute one of the first causes of death globally. For this reason the development of noninvasive methods to quantify arterial stiffness have had great impact. The purpose of this paper is the study of the noninvasive measurement method of brachial ankle pulse wave velocity (baPWV). To perform this study pressure waveforms in the arterial system were simulated, by using a one-dimensional model. With these pressure waveforms baPWV's values were calculated, and were compared with two others calculated methods: cfPWV (carotid-femoral PWV, gold standard method), and PWVteor (Bramwell-Hill equation). Significant correlations were obtained, r=0.967 y r=0.9828 respectively. The sensibility of the baPWV method to the stiffness change, represented for the distensibility change, was investigated, and we conclude that baPWV method is sensitive to the changes that take place in both central and peripheral arteries.

Epidemiology of bovine tuberculosis in Mexico, bordering the United States, at establishment of controlling strategies / Epidemiologia da tuberculose bovina na fronteira do México com os Estados Unidos, por ocasião do estabelecimento das estratégias de controle

A case-control study was carried out for determining epidemiological patterns at the beginning of the Mexican campaign against bovine tuberculosis (BTB) in the State of Tamaulipas, Mexico, bordering the United States of America. From January 1995 to March 1998, 599 direct tissue smears of cattle from routine slaughterhouse inspection were analyzed for the presence of Mycobacterium bovis acid-fastness with Ziehl-Neelsen stain. BTB status was associated with year of diagnosis, age, breed, geographical origin of cattle, and type of slaughterhouse using the odds ratio (OR) (95 percent confidence level). The prevalence at slaughterhouse surveillance was 15.36 percent, which was considerably higher in 1995 (41.38 percent, OR=5.78, P<0.0001), in comparison with 8.09 percent, 14.42 percent, and 10.14 percent for the years 1996, 1997, and 1998, respectively. BTB was associated with cattle from the State of Tamaulipas (19.73 percent, OR= 4.438, P=0.01), adult cattle (19.13 percent, OR=2.19, P<0.0001), Bos taurus (22.54 percent, OR=2.135, P<0.0001) and B. taurus x B. indicus cross bred animals (29.31 percent, 2.769, P<0.0001), and cattle slaughtered at federal inspected abattoir (17.58 percent, OR=1.23, P<0.0001).

O estudo foi realizado para determinar os padrões epidemiológicos no início da campanha mexicana contra a tuberculose bovina (BTB), no Estado de Tamaulipas, fronteira com os Estados Unidos da América. De janeiro de 1995 a março de 1998, 599 amostras de tecidos bovinos, obtidas em inspeção de rotina em abatedouros, foram analisadas para a presença de Mycobacterium bovis, fixadas em corante Ziehl-Neelsen. O status BTB foi associado ao ano do diagnóstico, idade, raça e origem geográfica do bovino utilizando a razão de probabilidade (OR) (com intervalo de confiança de 95 por cento). A prevalência no abatedouro sob inspeção foi de 15,36 por cento, consideravelmente maior em 1995 (41,38 por cento, OR=5,78), P<0,0001) em relação a 8,09 por cento, 4,42 por cento e 10,14 por cento para 1996, 1997 e 1998, respectivamente. Houve associação entre BTB e animais provenientes do estado de Tamaulipas (19,73 por cento; OR=0.438; P=0.01), idade adulta (19,13 por cento; OR=2,19; P<0,0001), Bos taurus (22,54 por cento; OR=2,135; P<0,0001) e cruzamentos B. taurus x B. indicus (29,31 por cento; 2,769; P<0,0001), e animais abatidos em abatedouros federais inspecionados (17,58 por cento; OR=1,23; P<0,0001).

Efficacy of celecoxib in treating symptoms of viral pharyngitis: a double-blind, randomized study of celecoxib versus diclofenac.

This study compared the efficacy and safety of the cyclooxygenase-2 specific inhibitor celecoxib with the conventional non-steroidal anti-inflammatory drug diclofenac in the symptomatic treatment of viral pharyngitis. Adult patients from 27 study centers in Latin America were treated with oral doses of celecoxib 200 mg once daily or 200 mg twice daily, or diclofenac 75 mg twice daily for 5 days in a double-blind, randomized study. The primary efficacy assessment was 'Throat Pain on Swallowing' on day 3. In addition, secondary quality-of-life assessments were performed on days 3 and 5. All adverse events and treatment-emergent signs and symptoms were recorded. Data from 313 patients were evaluable for efficacy (105 celecoxib 200 mg once daily, 107 celecoxib 200 mg twice daily, 101 diclofenac 75 mg twice daily). The upper 95% confidence limits for the visual analog scale of 'Throat Pain on Swallowing' on day 3 for celecoxib 200 mg once daily relative to diclofenac 75 mg twice daily, and celecoxib 200 mg twice daily relative to diclofenac 75 mg twice daily were 9.26 and 7.83, respectively. All secondary efficacy and quality-of-life measures were clinically similar for the three treatment groups, and no statistically significant differences were detected. The incidences of treatment-emergent adverse events and withdrawals due to adverse events were similar for all groups, but numerically higher among patients taking diclofenac than celecoxib. More patients in the diclofenac group reported gastrointestinal complaints (7.3%) compared with those in the celecoxib groups (4.3% in the celecoxib 200 mg once-daily group and 3.4% in the celecoxib 200 mg twice-daily group). In conclusion, 5 days of treatment with celecoxib 200 mg once daily is as effective as diclofenac 75 mg twice daily in the symptomatic treatment of viral pharyngitis. Celecoxib 200 mg once daily is also as effective as celecoxib 200 mg twice daily in this condition.

Acute fulminant hepatic failure in a woman treated with phenytoin and trimethoprim-sulfamethoxazole.

Massive hepatic necrosis following exposure to phenytoin and trimethoprim-sulfamethoxazole is a rare occurrence and to the best of our knowledge has not been reported previously. Acute hepatic failure following administration of trimethoprim-sulfamethoxazole has rarely been seen, and only 4 cases have been well documented pathologically. We report a case of acute liver failure in a 60-year-old woman following ingestion of phenytoin and trimethoprim-sulfamethoxazole concomitantly over a 9-day period. Autopsy findings revealed acute fulminant hepatic failure. This case demonstrates the effects of chemical-chemical interactions in the potentiation of hepatotoxicity of single agents and specifically illustrates the need for discontinuing trimethoprim-sulfamethoxazole in the presence of early liver injury.

Angiogenesis in early-invasive and low-malignant-potential epithelial ovarian carcinoma.

OBJECTIVE: To evaluate angiogenesis in ovaries of women with stage I invasive and low-malignant-potential epithelial ovarian carcinoma. METHODS: Ovarian specimens of 49 consecutive women with primary stage I invasive (n = 15) or stage I low-malignant-potential epithelial ovarian carcinoma (n = 34) were stained immunohistochemically for factor VIII-related antigen. Microvessel counts were tested for correlation with patient age, race, parity, previous oral contraceptive use, histologic type, tumor grade, tumor size, ascites, tumor excrescences, and disease-free and overall survival. Statistical analysis included multiple linear regression, Student t tests, factorial analysis of variance, and Cox proportional hazards regression, with P <.05 considered statistically significant. RESULTS: Microvessel counts of ovarian specimens of women with stage I invasive epithelial ovarian carcinoma (median 30, range 17-73) were significantly higher than those of women with stage I low-malignant-potential epithelial ovarian carcinoma (median 10, range 5-23), (P <.001). Among women with low-malignant-potential disease, microvessel counts did not differ significantly between serous and mucinous carcinomas (median 10, range 5-23 versus median 11, range 5-20, respectively, P =.78). There was no correlation between microvessel counts and age, tumor grade, tumor size, ascites, or tumor excrescences. CONCLUSION: Angiogenesis as assessed by microvessel counts is more intense in stage I invasive ovarian epithelial carcinoma compared with stage I low-malignant-potential carcinoma, and might assist in differentiating between these histopathologic entities.

Upper body obesity and hyperinsulinemia are associated with anovulation.

The objective of this study was to determine the effect of body fat distribution and hyperinsulinemia on the occurrence of ovulation. Fifty-six women (20-35 years old) either with overweight or obesity (body mass index >/=25) were studied. They were classified in two groups according to waist/hip ratio (WHR); one with predominance of adiposity in the upper body segment (n = 29, WHR >0.85) and the other with predominant adiposity in the lower body segment (n = 27, WHR

Effect of intravenous immunoglobulin G on natural killer cell cytotoxicity in vitro in women with recurrent spontaneous abortion.

Intravenous immunoglobulin (IVIg) has been used to treat women with recurrent spontaneous abortion (RSA), particularly for women with elevated natural killer (NK) cells. We investigated the effect of IVIg on peripheral blood NK cell activity in vitro in women with RSA. 51Cr-release assays using K562 in the presence of varying concentrations of IVIg were performed using PBL from 16 women with RSA. Antibody dependent cellular cytotoxicity (ADCC) was evaluated using Daudi cells. Effectors and targets were preincubated with IVIg. Binding of IVIg to K562 and Daudi was evaluated by flow cytometry. The effect of K562 absorbed IVIg on NK activity was compared to that of non-absorbed IVIg. NK cytotoxicity and ADCC in the presence of F(ab')2 fragments were compared with those in the presence of intact IVIg. IVIg produced a significant, dose dependent inhibition of NK activity in vitro. Inhibition of NK activity occurred when effectors but not targets were preincubated with IVIg. IVIg binds to K562 and Daudi. IVIg increased ADCC when targets but not effectors were incubated with IVIg. K562 absorbed IVIg produced more inhibition of NK cytotoxicity than non-absorbed IVIg. Suppression of NK cytotoxicity by F(ab')2 was as effective as that of IVIg. However, F(ab')2 did not increase ADCC. IVIg effectively reduces peripheral blood NK cytotoxicity in vitro. Inhibition of NK cytotoxicity is mediated at the effector cell level through the antigen binding portion of the immunoglobulins. Women with RSA and elevated NK cells may benefit from IVIg treatment.

Intravenous immunoglobulin inhibits natural killer cell activity in vivo in women with recurrent spontaneous abortion.

We previously reported elevation of natural killer (NK) cells in women with recurrent spontaneous abortion (RSA) of immune etiology. In this study, we investigated the effect of intravenous immunoglobulin G (IVIg) on peripheral blood NK activity in vivo in women with RSA. Blood was drawn prior to and 7-11 days after IVIg therapy in eight women with RSA. NK activity was measured using K562 as target cells for 51Cr-release assays. Serum IgG concentrations were also measured. All received 400 mg/kg/day of IVIg for 3 consecutive days. 1) Seven of eight women became pregnant. Five delivered a live born infant. Three out of five women (60%) who delivered a live born infant showed a significant inhibition of NK cytotoxicity post IVIg and the rest did not show any changes; 2) NK cytotoxicity was significantly increased in a woman who miscarried again; 3) A woman who miscarried a chromosomally abnormal fetus showed a significant inhibition of NK cytotoxicity after IVIg; and 4) Serum IgG concentration increased significantly from 9.3 +/- 3.0 mg/ml to 23.5 +/- 5.1 mg/ml post IVIg therapy. IVIg effectively inhibits peripheral blood NK activity in vivo. These results are consistent with our previous finding showing that IVIg inhibits NK cell activity in vitro. Women with RSA and elevated NK cells may benefit from IVIg treatment.

Immunophenotypic profiles of peripheral blood lymphocytes in women with recurrent pregnancy losses and in infertile women with multiple failed in vitro fertilization cycles.

In summary (1) Nonpregnant women with RSAs of unknown etiology have higher levels of CD56+ lymphocytes when compared to normal controls; (2) The levels of CD19+, CD56+, and CD56+/CD16+ PBL of pregnant women with RSA are significantly higher than those of multiparous pregnant normal controls; (3) Women with autoantibodies to phospholipids have significantly higher levels of elevated CD56+ and CD56+/CD16+ lymphocytes when compared to women without antiphospholipid antibodies; (4) Women with autoantibodies to nuclear components demonstrate higher numbers of CD19+/CD5+ cells compared to women without autoantibodies to nuclear components; (5) Idiopathic infertile women with multiple prior IVF failures demonstrate significantly higher levels of CD56+ pBL than normal fertile controls and the conception rate is much higher in those with CD56+ levels less than 12%; (6) Elevations of CD56+ lymphocytes to over 18% during a pregnancy is a good prognostic indicator of impending pregnancy loss. We have not seen a liveborn infant in women with levels of 18% or higher without IVIg therapy; and (7) Infertile and RSA women who fail alloimmune and autoimmune therapy have significant alterations in cellular and humoral immunity involving NK cells and CD19+/CD5+ B cells.

Up-regulated expression of CD56+, CD56+/CD16+, and CD19+ cells in peripheral blood lymphocytes in pregnant women with recurrent pregnancy losses.

PROBLEM: To analyze immunophenotypic profiles of peripheral blood and humoral autoimmune responses in women with a history of recurrent spontaneous abortions (RSA). METHOD: Peripheral blood lymphocyte subsets by flow cytometry and autoantibodies to phospholipids and nuclear components by ELISA were measured in nonpregnant and pregnant women with RSA of unknown etiology. Thirty-five pregnant and eighty-one nonpregnant women with RSA were studied. Seventeen nonpregnant and twenty-two pregnant normal controls were included. RESULTS: Natural killer (NK) cells (CD56+) were significantly elevated in nonpregnant women with RSA as compared with nonpregnant controls. Pregnant women with RSA demonstrated significantly increased NK (CD56+, CD56+/CD16+) and B cells (CD19+) as compared with pregnant controls. Women who miscarried the index pregnancy demonstrated significantly lower CD3+ cells in comparison with normal controls. Women with RSA and antiphospholipid antibodies showed significantly elevated NK cells when compared with women without antiphospholipid antibodies. Women with autoantibodies to nuclear components demonstrated significantly elevated CD19+/CD5+ cells when compared to women without autoantibodies to nuclear components. CONCLUSIONS: Women with RSA demonstrate an abnormal cellular immune response by increasing peripheral natural killer cells and B cells as compared with normal controls.

Autoantibodies to phospholipids and nuclear antigens in non-pregnant and pregnant Colombian women with recurrent spontaneous abortions.

Autoantibodies to negatively charged phospholipids have been reported to be associated with thrombotic events, thrombocytopenia and adverse pregnancy outcome, such as intrauterine growth retardation and recurrent spontaneous abortions (RSAs). In this study, autoantibodies to 6 phospholipid antigens and antinuclear antibody (ANA) were tested in Colombian women with a history of RSAs. Sixty-eight non-pregnant and 25 pregnant women with a history of RSAs comprised the study group. Twenty-five non-pregnant normal healthy women and thirty-one normal pregnant women served as controls. The non-pregnant women with RSAs showed a higher incidence of autoantibodies to cardiolipin (23% positive) as compared with non-pregnant normal controls (0% positive; P < 0.005). The incidence of autoantibodies to cardiolipin (28%; P < 0.005), phosphatidylethanolamine (16%; P < 0.005), phosphatidylserine (16%; P < 0.05), phosphatidylglycerol (16%; P < 0.05), phosphatidic acid (16%; P < 0.01) and phosphatidylinositol (20%; P < 0.01), in the pregnant women with RSAs was significantly higher than that of normal pregnant controls. There was no difference in the incidence of ANA in either group. In conclusion, women with a history of RSAs have a higher incidence of autoantibodies to phospholipids when compared to pregnant and non-pregnant normal controls. Autoimmune serological work-up is indicated during pregnancy in women with a history of RSAs.

Caracterización hormonal de los adenomas hipofisarios no funcionantes / Hormonal characterization of the non fuctioning pituitary adenomas

Se estudiaron 98 pacientes con adenomas no funcionantes, 34 hombres y 64 mujeres, realizando un estudio hormonal en suero para conocer su perfil endocrino. Con tal objeto, se efectuaron determinaciones de hormona folículo estimulante y hormona luteinizante (FSH, LH), prolactina (PRL), estadiol (E2), testosterona (T), cortisol, hormona del crecimiento (GH), hormona adrenocorticotrópica (ACTH), hormona estimulante del tiroides (TSH) y gastrina (Ga) por radioinmunoanálisis. Los resultados mostraron marcado hipergonadotropismo en el 47//de los pacientes, con niveles séricos de FSH y LH muy elevados y un incremento inesperado de la concentración de Ga (Grupo I). En contraste, el resto de los pacientes tuvo concentraciones normales o bajas de gonadotrofinas y Ga (Grupo II). El grupo I mostró una relación inversa entre los niveles de gonadotropinas y esteroides gonadales (E2 o T) con cifras significativamente menores que los valores normales y los encontrados en el Grupo II (<0,00l) en el cual la relación fue lineal positiva. Tambien se observó una relación directa entre la concentración de FSH conTSH (r=0,75) y Ga (r=0,80), probablemente por los neurotransmisores que determinan la secreción de estas hormonas. La TSH al igual que las hormonas tiroideas, tuvo cifras más elevadas en el Grupo I, mientras que los valores de PRL fueron más bajos (P<0,0001). La concentración de GH y ACTH fuer normal en ambos,no obstante,el 33 por ciento de los pacientes del Grupo II presentó hipocortisolismo e hipotiroidismo. La edad promedio de los pacientes analizada por décadas, no fue estadísticmente diferente entre los grupos y no explica las diferencias encontradas, aunque en el Grupo I predominaron las mujeres. En éstas, la elevación de FSH podría estar condicionada por la deficiencia gonadal, acorde a la edad de las pacientes (49,8 9,6 años), sin embargo, algunos valores fueron extraordinariamente elevados y existe la posibilidad de que la hipófisis en condiciones patológicas, como es la forma adenomatosa,pueda producir en forma autónoma,moléculas de LH y FSH alteradas y carentes de actividad biológica, o bien, subunidad O libre, como se ha demostrado en algunos gonadotropomas. Por otra parte, algunos de los casos con TSH elevada podrían considerarse verdaderos TS-Homas, que no suprimen su secreción a pesar de la elevada concentración de hormonas tiroideas. Así, podría decirse que dentro de los no funcionantes, están enmarcados algunos de estos adenomas. Se concluye que, desde el punto de vista hormonal, los adenomas del Grupo II son los verdaderos no funcionantes

Caracterización hormonal de los adenomas hipofisarios no funcionantes / Hormonal characterization of the non fuctioning pituitary adenomas

Se estudiaron 98 pacientes con adenomas no funcionantes, 34 hombres y 64 mujeres, realizando un estudio hormonal en suero para conocer su perfil endocrino. Con tal objeto, se efectuaron determinaciones de hormona folículo estimulante y hormona luteinizante (FSH, LH), prolactina (PRL), estadiol (E2), testosterona (T), cortisol, hormona del crecimiento (GH), hormona adrenocorticotrópica (ACTH), hormona estimulante del tiroides (TSH) y gastrina (Ga) por radioinmunoanálisis. Los resultados mostraron marcado hipergonadotropismo en el 47//de los pacientes, con niveles séricos de FSH y LH muy elevados y un incremento inesperado de la concentración de Ga (Grupo I). En contraste, el resto de los pacientes tuvo concentraciones normales o bajas de gonadotrofinas y Ga (Grupo II). El grupo I mostró una relación inversa entre los niveles de gonadotropinas y esteroides gonadales (E2 o T) con cifras significativamente menores que los valores normales y los encontrados en el Grupo II (<0,00l) en el cual la relación fue lineal positiva. Tambien se observó una relación directa entre la concentración de FSH conTSH (r=0,75) y Ga (r=0,80), probablemente por los neurotransmisores que determinan la secreción de estas hormonas. La TSH al igual que las hormonas tiroideas, tuvo cifras más elevadas en el Grupo I, mientras que los valores de PRL fueron más bajos (P<0,0001). La concentración de GH y ACTH fuer normal en ambos,no obstante,el 33 por ciento de los pacientes del Grupo II presentó hipocortisolismo e hipotiroidismo. La edad promedio de los pacientes analizada por décadas, no fue estadísticmente diferente entre los grupos y no explica las diferencias encontradas, aunque en el Grupo I predominaron las mujeres. En éstas, la elevación de FSH podría estar condicionada por la deficiencia gonadal, acorde a la edad de las pacientes (49,8 Ð 9,6 años), sin embargo, algunos valores fueron extraordinariamente elevados y existe la posibilidad de que la hipófisis en condiciones patológicas, como es la forma adenomatosa,pueda producir en forma autónoma,moléculas de LH y FSH alteradas y carentes de actividad biológica, o bien, subunidad Ó libre, como se ha demostrado en algunos gonadotropomas. Por otra parte, algunos de los casos con TSH elevada podrían considerarse verdaderos TS-Homas, que no suprimen su secreción a pesar de la elevada concentración de hormonas tiroideas. Así, podría decirse que dentro de los no funcionantes, están enmarcados algunos de estos adenomas. Se concluye que, desde el punto de vista hormonal, los adenomas del Grupo II son los verdaderos no funcionantes

[Effect of primary ovarian insufficiency on the molecular heterogeneity of pituitary gonadotropins]. / Efecto de la insuficiencia ovárica primaria sobre la heterogeneidad molecular de las gonadotropinas hipofisarias.

It is known that hypophysial gonadotropins circulate in different molecular forms which are provided with different biological activity and that the proportion of such varieties keep a relation with the concentrations of estrogens in circulation. In physiological menopause predominate the great molecular forms which have a lesser biological activity and when estrogens are administrated a change is produced to smaller molecular forms. The present study tries to determine if in cases of ovarian insufficiency of long duration as in precocious menopause and the syndrome of refractory ovary the chromatographic conduct of gonadotropin is similar. Six patients with precocious menopause, and three with the syndrome of refractory ovary, were studied, in order to make a comparison of chromatographic pattern of FSF and LH in serum, with the one found in women with normal ovarian function and with physiologic menopause. The chromatographic analysis was done by filtration in gel of the serum and the subsequent determination of LH and FSH by RIA of double antibody. It was found that the chromatographic pattern of patients with ovarian insufficiency of long duration, characteristically presents larger molecular forms, specially in the refractory ovary syndrome with a greater alteration in the profile of LH. With base on these results it is concluded that the duration of ovarian insufficiency determine the type of molecular form, predominant, of gonadotropins. Also it is suggested that for the syndrome of refractory ovary, the greater heterogenicity of gonadotropins may explain part of physiopathogeny.

Distribution of follicle-stimulating hormone and luteinizing hormone isoforms in sera from women with primary ovarian failure compared with that of normal reproductive and postmenopausal women.

OBJECTIVE: To demonstrate if molecular heterogeneity of gonadotropins correlates with the type of primary gonadal failure. DESIGN AND METHODS: Aliquots of sera from women with hypogonadism were subjected to gel filtration chromatography to be assayed for follicle-stimulating hormone (FSH) and luteinizing hormone (LH) by the use of radioimmunoassay. Molecular weight (MW) of isoforms was calculated on a calibration curve obtained with molecular markers. The molecular variants were characterized on the basis of elution volume, MW, and partition coefficient. RESULTS: Chromatographic profile of sera from four women with natural menopause exhibited two FSH peaks of immunoreactivity and a heavier LH isoform. This pattern was different from that obtained in sera from women of reproductive age who presented a single peak that eluted after the corresponding standard. In six cases of idiopathic premature menopause and three more with gonadotropin-resistant ovary, the chromatographic profile showed a marked and remarkable molecular heterogeneity, particularly LH, and this was more apparent in women with resistant ovary. CONCLUSIONS: Our investigation confirms the relationship between the gonadotropin heterogeneity with the gonadal failure. The duration of the ovarian failure may influence the molecular proportion of gonadotropins and the predominance of heavier MW isohormones.

[The distribution of adipose tissue is related to the levels of insulin in the obese woman]. / La distribución del tejido adiposo tiene relación con los niveles de insulina en la mujer obesa.

We studied 51 patients aged 20-35 years, with overweight or obesity evaluated by the body mass index (BMI = weight height2) when it was higher than 25 (normal 20-25), and a control group of six women with the same age and normal BMI. In all patients waist and hip circumferences were measured, to calculate the waist/hip ratio (WHR). Also serum insulin was measured in basal conditions and as response to 75 g oral glucose load, taking samples at 30, 60, 90, 120 and 180 minutes after. The test were performed 3 to 6 days following a spontaneous or induced genital bleeding with progestin. The WHR showed a normal distribution with the greatest frequency at 0.87. The patients were classified with predominance of adiposity in the upper body segment, when the WHR was equal or more than 0.85, and with adipose predominance in the lower body segment when it was equal or less than 0.84. The average insulin values in response to oral glucose load of patients with upper body segment obesity were significantly higher (Mann-Whitney's U = 0, p less than 0.02) than the corresponding cases with lower body segment obesity. Besides, there was a significant correlation between WHR and serum insulin values at 30 minutes after the oral glucose load (Pearson's r = 0.331, p less than 0.02). These results suggest a relation between the distribution of adiposity and insulin values, which were higher in patients with adipose predominance in the upper body segment.

[Prolactin variants in serum and amniotic fluid of women with ovulatory hyperprolactinemia]. / Variantes de prolactina en suero y líquido amniótico de mujeres con hiperprolactinemia ovulatoria.

There is enough evidence that prolactin (PRL), like many other pituitary hormones, is composed by multiple forms that differ from each other by size charge. Although they can be seen in the pituitary glands of a variety of species, their biological significance, identity and chemical nature still remain poorly understood. Recently, a new syndrome characterized by normal ovarian function in the presence of sustained hyperprolactinemia has been reported by our group. In these women, highly abnormal percentages of serum big big PRL have been consistently demonstrated. This observation suggests that big big PRL is immunologically similar, but biologically less active than monomeric or little PRL. In this study we have determined then molecular size heterogeneity of immunoreactive PRL in serum and amniotic fluid from two ovulatory hyperprolactinemic subjects (subjects A and B) who had, under non-pregnant conditions, large amounts of serum big big PRL, throughout different stages of parturition. Control subjects consisted of two women at the end of pregnancy in whom PRL species demonstrated a normal size distribution (subjects C and D). Mean basal levels of PRL were the highest in subjects A and B and remained constant during labor. In the control subjects a remarkable decline in PRL levels was observed during the periparturitional period. This pattern of PRL release was not correlated with changes in steroid hormone concentrations. The relative proportions of PRL size variants throughout delivery showed no apparent changes in all four subjects.(ABSTRACT TRUNCATED AT 250 WORDS)