Amelogenin Peptide-Chitosan Hydrogel for Biomimetic Enamel Regrowth.

We designed synthetic peptides that have demonstrated an effective remineralization potential to restore incipient enamel decay. In order to develop a clinically viable approach we incorporated the amelogenin-derived peptides P26 and P32 into chitosan hydrogel and examined their efficacy in the remineralization of enamel. Peptides in chitosan exhibited increased stability in vitro as compared to peptides in solution at room temperature and at 37°C. Tooth models for enamel erosion (sections) and white spot lesions (blocks) were subject to periods of demineralization. Treatment groups were subjected to remineralization in artificial saliva in the presence of P26 and P32 in solution and in chitosan hydrogel (P26-CS and P32-CS). Quantitative light-induced fluorescence (QLF) was employed to analyze mineral density following demineralization and remineralization across all the treatment groups. Scanning electron microscopy and nanoindentation were used to characterize the surface structure and mechanical strength of regrown enamel. Control enamel sections treated in artificial saliva demonstrated randomly distributed, tiny, needle-shaped crystals with a low packing density and porosities displaying mineralization defects. In samples treated with P26-CS or P32-CS a denser coating of organized hydroxyapatite (HAP) crystals was formed covering the entire surfaces of demineralized enamel window. The hardness and modulus of enamel surfaces were increased after treatment with P26-CS and P32-CS with no significant difference in the mechanical properties between the two peptide hydrogels. Analysis of mineral density by QLF showed that in enamel sections P26 peptide alone or P26-CS significantly enhanced the remineralization. In enamel blocks P26 in solution had a better efficacy than P26-CS.

Time-course study of cellular immune response and testosterone metabolism in an autoimmune model for chronic prostatic inflammation.

PURPOSE: Little is known of the etiology and pathogenesis of chronic inflammatory prostate diseases of noninfectious origin. In our experimental autoimmune rat model for chronic prostatic inflammation (CPI) we evaluated, in a time-course study, the specific cellular immune response to male accessory glands (MAG) and metabolic activity in the prostate gland. Results obtained in CPI rats were compared with data from rats immunized with kidney homogenate as well as from non-treated rats. MATERIALS AND METHODS: Specific cellular immune response against MAG antigen(s) was studied by delayed type hypersensitivity (DTH) and lymphocyte proliferation tests. The prostate 5alpha-reductase activity was studied in prostate homogenates by thin layer chromatography (TLC). RESULTS: DTH values were positive in MAG treated rats sacrificed at days 7 and 28 after first immunization (FI) (p < or = 0.05) in relation to kidney treated and non-treated rats. When we analyzed the proliferative responses to MAG antigen(s), an antigen specific proliferation, as shown by the mean [3H]thymidine uptake (cpm), was observed in rats sacrificed on days 14 and 28 (p < or = 0.05) after FI. The metabolic studies indicated that the 5alpha-reductase activity decreased slightly in MAG treated groups at day 14 after FI and diminished significantly at the end of CPI development. CONCLUSION: These data reveal that the prostatic endocrine cell destruction during CPI could be a consequence of immune/inflammatory cell mediated processes.

Experimental autoimmune prostatitis: in vivo induction of the autoimmune response to lymphocytic soluble factors. Alterations at the endocrine metabolism level.

PROBLEM: In rats, immunization with male accessory gland (MAG) extract promotes experimental autoimmune vesicle prostatitis. A specific mononuclear cell-mediated immune response and prostate androgen metabolism impairment in MAG-immunized rats were observed. The possibility that lymphocytic soluble factors (SoFs) can regulate the local steroid metabolism in these rats directly was studied. We investigated whether the SoFs released by MAG-sensitized lymphocytes are capable of modifying the prostatic androgen metabolism and whether they induce histologic lesions "in vivo" when they are inoculated, carried by liposomes, into untreated rats. METHOD OF STUDY: "In vitro" enzymatic [3H]-5 alpha-dihydrotestosterone bioconversion and histologic studies were performed with prostates from SoF-treated rats (LK rats). The obtained 3 alpha/beta-hydroxysteroid-oxidoreductase activities showed that LK rat values were significantly lower than in controls: 79.0 +/- 2.5 vs 158.7 +/- 10.2 pmol/min/mg protein, respectively (P < 0.01). RESULTS: In the histologic studies, LK rat prostates showed focalized mononuclear infiltrates of various degrees, whereas control rats showed non-atypic modification of the gland. CONCLUSION: These results indicate that SoFs (probably total lymphokines) contribute significantly to the pathogenesis of experimental autoimmune prostatitis, involving a biochemical relationship between immune reaction and the androgenic enzymatic inhibition in the prostate.

Effect of male accessory glands autoaggression on androgenic cytosolic and nuclear receptors of rat prostate.

The effect of immunization against male accessory gland (MAG) homogenates over androgenic cytosolic and nuclear receptors of rat prostate was studied. In the MAG-immunized rats the Bmax of cytosolic receptors was significantly increased (120.3 +/- 44.3 vs 47.7 +/- 24.9 fmol/mg protein, p less than 0.01, mean +/- SD). In contrast, the Bmax of nuclear receptors in the MAG-immunized rats showed no significant difference as regarded controls (kidney immunized rats) when expressed as fmol/100 micrograms DNA (196.1 +/- 84.8 vs 148.3 +/- 88.9) but it show to slight differences (p less than 0.1) when data were reported as percent of weight of tissue (2,189 +/- 918.6 vs 1,303 +/- 611.2 fmol/g wet issue). Results (mean +/- SD) on binding affinity of cytosolic receptors showed no significant differences in MAG-immunized rats as compared with controls (Kd: 1.98 +/- 0.66 vs 1.92 +/- 0.20 nM). Likewise, only a slight difference between both groups was attained for Kds of nuclear receptors (2.34 +/- 0.28 vs 1.80 +/- 0.62 nM, p less than 0.2). On the other hand, 5 alpha 1-dihydrotestosterone (DHT) values obtained in prostate homogenates were significantly decreased in MAG-immunized rats as compared with controls (17.4 +/- 2.0 vs 7.1 +/- 0.9 ng/g tissue, mean +/- SD, p less than 0.01). However, testosterone (T) levels in gland tissue showed no significant differences between both groups (2.4 +/- 0.5 vs 2.6 +/- 0.3 ng/g tissue) with an increase in the T: DHT ratio from 0.14 to 0.37.(ABSTRACT TRUNCATED AT 250 WORDS)

Valores de la yoduria en muestras de la población de diversas zonas de la Provincia de Córdoba en relación al bocio endémico / Valuation of urinary iodine excretion in different areas of the Province of Córdoba in relation with endemic goiter

Se determinaron yodurias de 324 escolares de 5 a 17 años, de ambos sexos, en cinco zonas sanitarias (Z.S.) rurales de la provincia de Córdoba, diferenciados según su edad y detallando la condición socio-económica de cada individuo (Z.S. 1, al Norte, Departamento Tulumba; 2, al Oeste, Departamento San Alberto; 3, al Centro, Departamento Santa María; 4, al Este, Departamento San Justo; 7, al Sur, Departamento Río IV) y en 49 adultos, ambos sexos, residentes en la ciudad de Córdoba, para estudiar si la ingesta de yodo es adecuada, tamándose Río IV como zona control de referencia. En dos zonas se encontraron altos porcentajes de escolares con excreción subnormal de yodo (grupo III de Follis): San Vicente, Dpto. San Alberto, 15%, Alto del Durazno, Dpto. Santa María, 30% del total con valores disminuidos. Todas las localidades restantes analizadas, con valores que se corresponden con los grupos I y II (normales y ligeramente disminuidos respectivamente). Se completa el trabajo con: a) un estudio comparativo entre orinas de 24h y muestras casuales respecto a la expresión de los resultados, y b) la incidencia del sexo en los valores hallados. Se preconiza el empleo de muestras casuales de orina para estudios complementarios de campo. Se concluye que no existen diferencias en la yoduria respecto a la condición socioeconómica, y las diferencias dadas por el sexo y edad se corrigen mediante el uso de factores ad-hoc

Valores de la yoduria en muestras de la población de diversas zonas de la Provincia de Córdoba en relación al bocio endémico / Valuation of urinary iodine excretion in different areas of the Province of Córdoba in relation with endemic goiter

Se determinaron yodurias de 324 escolares de 5 a 17 años, de ambos sexos, en cinco zonas sanitarias (Z.S.) rurales de la provincia de Córdoba, diferenciados según su edad y detallando la condición socio-económica de cada individuo (Z.S. 1, al Norte, Departamento Tulumba; 2, al Oeste, Departamento San Alberto; 3, al Centro, Departamento Santa María; 4, al Este, Departamento San Justo; 7, al Sur, Departamento Río IV) y en 49 adultos, ambos sexos, residentes en la ciudad de Córdoba, para estudiar si la ingesta de yodo es adecuada, tamándose Río IV como zona control de referencia. En dos zonas se encontraron altos porcentajes de escolares con excreción subnormal de yodo (grupo III de Follis): San Vicente, Dpto. San Alberto, 15%, Alto del Durazno, Dpto. Santa María, 30% del total con valores disminuidos. Todas las localidades restantes analizadas, con valores que se corresponden con los grupos I y II (normales y ligeramente disminuidos respectivamente). Se completa el trabajo con: a) un estudio comparativo entre orinas de 24h y muestras casuales respecto a la expresión de los resultados, y b) la incidencia del sexo en los valores hallados. Se preconiza el empleo de muestras casuales de orina para estudios complementarios de campo. Se concluye que no existen diferencias en la yoduria respecto a la condición socioeconómica, y las diferencias dadas por el sexo y edad se corrigen mediante el uso de factores ad-hoc (AU)

Testosterone metabolism in vitro by male sexual accessory glands from normal and autoimmunized rabbits.

In vitro metabolism of (3H)-testosterone from male accessory gland homogenates from autoimmunized and normal rabbits was studied at different times of incubation. Results indicated that 5 alpha - androstane-3 alpha, 17 beta-diol was the main metabolite formed in both cases, though the presence of the 3 beta-isomer cannot be excluded. On autoimmunized rabbits with small histological alteration, transformation of the precursor (3H)-testosterone was significantly greater (40 min: P less than 0.01; 60 min: P less than 0.05). This led to a higher yield of 5 alpha-androstane-3 alpha, 17 beta-diol at both incubation times, being significant only at 40 min (P less than 0.02). The 4-androstene-3,17-dione also increased as compared with the normal group. In autoimmunized rabbits with a greater histological alteration, the bioconversion of (3H)-testosterone decreased for both incubation times, being significant only for the 40 min (P less than 0.05). A decreased interconversion to 4-androstene-3,17-dione was also observed, being significant only for 40 min (P less than 0.05). These results suggest that in an early stage of autoimmunization there might be a transient stimulation of enzyme activities in the sexual accessory glands. In another moment of the phenomena a more severe histological lesion with infiltration of male accessory glands was present. At the same time, decrease in the enzymatic activities could be noticed.

Testosterone metabolism in vitro by male sexual accessory glands from normal and autoimmunized rabbits

In vitro metabolism of (3H)-testosterone from male accessory gland homogenates from autoimmunized and normal rabbits was studied at different times of incubation. Results indicated that 5 alpha - androstane-3 alpha, 17 beta-diol was the main metabolite formed in both cases, though the presence of the 3 beta-isomer cannot be excluded. On autoimmunized rabbits with small histological alteration, transformation of the precursor (3H)-testosterone was significantly greater (40 min: P less than 0.01; 60 min: P less than 0.05). This led to a higher yield of 5 alpha-androstane-3 alpha, 17 beta-diol at both incubation times, being significant only at 40 min (P less than 0.02). The 4-androstene-3,17-dione also increased as compared with the normal group. In autoimmunized rabbits with a greater histological alteration, the bioconversion of (3H)-testosterone decreased for both incubation times, being significant only for the 40 min (P less than 0.05). A decreased interconversion to 4-androstene-3,17-dione was also observed, being significant only for 40 min (P less than 0.05). These results suggest that in an early stage of autoimmunization there might be a transient stimulation of enzyme activities in the sexual accessory glands. In another moment of the phenomena a more severe histological lesion with infiltration of male accessory glands was present. At the same time, decrease in the enzymatic activities could be noticed.

Testosterone metabolism in vitro by male sexual accessory glands from normal and autoimmunized rabbits.

In vitro metabolism of (3H)-testosterone from male accessory gland homogenates from autoimmunized and normal rabbits was studied at different times of incubation. Results indicated that 5 alpha - androstane-3 alpha, 17 beta-diol was the main metabolite formed in both cases, though the presence of the 3 beta-isomer cannot be excluded. On autoimmunized rabbits with small histological alteration, transformation of the precursor (3H)-testosterone was significantly greater (40 min: P less than 0.01; 60 min: P less than 0.05). This led to a higher yield of 5 alpha-androstane-3 alpha, 17 beta-diol at both incubation times, being significant only at 40 min (P less than 0.02). The 4-androstene-3,17-dione also increased as compared with the normal group. In autoimmunized rabbits with a greater histological alteration, the bioconversion of (3H)-testosterone decreased for both incubation times, being significant only for the 40 min (P less than 0.05). A decreased interconversion to 4-androstene-3,17-dione was also observed, being significant only for 40 min (P less than 0.05). These results suggest that in an early stage of autoimmunization there might be a transient stimulation of enzyme activities in the sexual accessory glands. In another moment of the phenomena a more severe histological lesion with infiltration of male accessory glands was present. At the same time, decrease in the enzymatic activities could be noticed.

Histological lesion and testosterone biosynthesis impairment in testes from autoimmune rabbits.

The aim of the present report is to study comparatively the biosynthesis of testosterone in normal and autoimmune rabbit testes, with different degrees of histological lesion, by in vitro double tracer incubation experiments. For this purpose (3H)-pregnenolone and (14C)-progesterone were used as precursors in the presence of testicular homogenates from both groups of animals. In the autoimmune animals, an impairment in the biotransformation of the precursors leading to a lesser synthesis of testosterone was demonstrated. An accumulation of dehydroepiandrosterone, 17 alpha-hydroxyprogesterone and androstenedione was frequently found. It was also shown that the metabolic impairment seemed to be produced at an earlier stage than the histological modifications. On the other hand, a correlation between the degree of testicular damage and the intensity of metabolic impairment could not be demonstrated conclusively.

[Solubilization and purification of a 3alpha-hydroxysteroid dehydrogenase in rat liver microsomes (author's transl)]. / Solubilisierung und Anreicherung einer 3alpha-Hydroxysteroid-Dehydrogenase aus Rattenleber-Mikrosomen

The microsomal 3-hydroxysteroid dehydrogenases were solubilized with lubrol, a non-ionic detergent. A 3alpha-hydroxysteroid dehydrogenase is purified about 100-fold by double affinity chromatography on 5alpha-dihydrotestosterone-Sepharose. This enzyme can use both NADH and NADPH as coenzymes.

Histological lesion and testosterone biosynthesis impairment in testes from autoimmune rabbits

The aim of the present report is to study comparatively the biosynthesis of testosterone in normal and autoimmune rabbit testes, with different degrees of histological lesion, by in vitro double tracer incubation experiments. For this purpose (3H)-pregnenolone and (14C)-progesterone were used as precursors in the presence of testicular homogenates from both groups of animals. In the autoimmune animals, an impairment in the biotransformation of the precursors leading to a lesser synthesis of testosterone was demonstrated. An accumulation of dehydroepiandrosterone, 17 alpha-hydroxyprogesterone and androstenedione was frequently found. It was also shown that the metabolic impairment seemed to be produced at an earlier stage than the histological modifications. On the other hand, a correlation between the degree of testicular damage and the intensity of metabolic impairment could not be demonstrated conclusively.