Retrospective Clinical Evaluation of RMGIC/GIC Class V Restorations.

The aim of this retrospective study was to evaluate the clinical performance of glass-ionomer cement (GIC) and resin-modified glass-ionomer cement (RMGIC) materials in Class V carious cervical lesions restored by dental students. Ninety-six (96) restorations performed with either GIC (Fuji IX) (n = 39) or RMGIC (Fuji II LC) (n = 57) were evaluated using the modified USPHS criteria by two independent investigators at two follow-up evaluations (two years apart). The Fisher statistical test was used to compare USPHS criteria and examine significant differences, with a significance level set at p < 0.05. The Kaplan-Meier algorithm was used to calculate the survival probability. The overall success rate of Class V restorations was 72.9% at the second follow-up evaluation, with restorations ranging in age from 2.5 to 3.5 years. The RMGIC (Fuji II LC) restorations exhibited a significantly higher overall success rate compared to the GIC (Fuji IX) restorations (p = 0.0104). Significant differences were observed in retention (p = 0.0034) and color match (p = 0.0023).

Ly49 knockdown in mice results in aberrant uterine crypt formation and impaired blastocyst implantation.

Genetic knockdown (KD) of the mouse Ly49 receptor family is reported to result in infertility despite the presence of zona-enclosed blastocysts in the uterus. Ly49 receptors regulate leukocyte functions particularly Natural Killer (NK) cell functions and are analogous to human killer immunoglobulin-like receptors (KIRs). Histological analyses of gd3.5-4.5 B6.Ly49(KD) uteri identified hatched but retarded blastocysts with pyknotic nuclei, aberrant endometrial crypt formation and impaired uterine lumen closure accompanied by a lack of primary decidualization These data support peri-implantation roles for leukocytes expressing the Ly49 receptor repertoire and may give insight into KIR-based regulation of human infertility.

Purificacion y actividad de la pepsina de pollo / Purification and assay of chicken pepsin

The proteolitic enzyme pepsin (EC 3.4.23.1) was purified from chicken stomach by a modification of the method of Bohak (1970): after homogenazing the raw material, the zymogen was extracted with NaCl and NaHCO3, activated with 3N HCl and precipitated with NaCl (28 per cent final concentration). The precipitate was lyophilised; fractions of it were suspended in 0.02N HCl. The solution was filtered through a column (2.6 x 80 cm) of Sephadex G-100 at an elution rate of 8-10 ml x cm-2 x h-1. Two protein peaks were obtained, the first one corresponding to the pepsin (2.0 mg/ml in pooled fractions). The milk clotting activity of the enzyme was determined on skimmed milk as a substrate (Berridge, 1955). Its proteolitic activity on the artificial substrate N-acetyl-L-phenylalanyl-L-3, 5-diiodo tyrosin (APD) also was determined (Rick-Fritsch, 1974). Mean clotting activity value was 5.52 UC, higher (P < 0.01) than that of the reference chymosin (0.64 UC). The activity with APD was unsatisfactory, due to very high absorbance values of the blanks. It is concluded, that the purification steps followed in this trial are simple and rapid, conferring a strong stimulus to using chicken pepsin as a clotting agent for the industrial production of pasteurized white cheese.

Extracción de la pepsina aviar (EC 3.423.1) y su utilización como substituto de la quimosina en la elaboración de queso blanco pasteurizado / Extraction of avian pepsin (EC 3.423.1) its utilization as chymosin substitute when the making white pasteurized cheese

Se extrajo pepsina aviar a partir de estómagos glandulares de aves, para ser utilizada como substituto de la quimosina en a elaboración de queso blanco pasteurizado. La enzima extraida demostró poseer un rendimiento de 4,3 g de pepsina aviar liofilizada por cada kilogramo de estómagos glandulares, y una actividad coagulante, sobre el substrato de Berridge, ocho veces superior a la quimosina utilizada como patrón de referencia. No se encontraron diferencias significativas en la composición química ni en la calidad organoléptica de los quesos fabricados, cuando se utilizó pepsina aviar, quimosina aviar, quimosina y la mezcla de ambos. Demostrándose que la substitución, tanto parcial como total, de la quimosina por la pepsina en queso blanco pasteurizado es factible, ya que ofrece una mayor actividad coagulante y un queso con características químicas y sensoriales similares a las obtenidas con el cuajo tradicional