Possible mechanisms involved in apoptosis of colon tumor cell lines induced by deoxycholic acid, short-chain fatty acids, and their mixtures

OBJECTIVE: To study the effects of cryopreservation on the quality of human testicular spermatozoa and the efficiency of intracytoplasmic sperm injection (ICSI) with frozen-thawed testicular sperm into metaphase II oocytes in vitro-matured from the germinal-vesicle stage oocyte. DESIGN: Preclinical freezing study on supernumarary testicular spermatozoa after ICSI. SETTING: Tertiary IVF center coupled with an institutional research environment. PATIENT(S): Twenty-nine patients undergoing excisional testicular biopsy for ICSI. INTERVENTION(S): Isolated testicular spermatozoa were cryopreserved and thawed; frozen-thawed motile testicular spermatozoa were microinjected. MAIN OUTCOME MEASURE(S): Prefreezing and post-thawing motility and viability, survival rate, fertilization rate, cleavage rate, and embryo quality after ICSI. RESULT(S): Mean percentage motility decreased from 21% before freezing to 6% after thawing. Vitality was impaired to a similar extent, decreasing from 68% to 22% (32% recovery rate). Injection of frozen-thawed testicular spermatozoa into in vitro-matured oocytes resulted in a fertilization rate of 50.9%. Cleavage rate was severely impaired. Half of the fertilized oocytes became arrested in the one-cell stage. CONCLUSION(S): Despite the low quality of the fresh testicular spermatozoa, a high percentage of prepared testicular sperm fractions showed survival and motility after the freezing and thawing process. Injection of frozen-thawed testicular sperm into matured oocytes resulted in fertilization rates comparable with these with fresh testicular sperm, but cleavage rates were severely impaired, which might be due to source of oocytes used for ICSI.     

The association of yogurt starters with Lactobacillus casei DN 114.001 in fermented milk alters the composition and metabolism of intestinal microflora in germ-free rats and in human flora-associated rats

The aim of this study was to compare the effects of milk and of various fermented milks on the composition and metabolic activities of the intestinal microflora. Groups of eight rats were fed for 6 wk a diet containing 30% nonfermented milk (M), yogurt (Y), milk fermented with Lactobacillus casei (LcFM) or milk fermented with the association of L. casei DN 114.001 and yogurt starters (LcYFM). In the first study, the survival of the lactic acid bacteria from the fermented milks was assessed by bacterial enumeration in feces of germ-free rats (GF rats) fed milk or fermented milks. The metabolic activities of the lactic acid bacteria were studied in these rats by the measurement of glycolytic activities and products of bacterial fermentation, i.e., acetate and lactate (isoforms L and D). In a second study, the effects of fermented milks on the composition and metabolism [gas, glycolytic activities, short-chain fatty acids (SCFA), alcohol and ammonia] of human flora were studied using human flora-associated rats (HF rats). In GF rats, the survival of L. casei in the feces did not differ between those fed the LcFM and LcYFM diets. L. bulgaricus was detected in the feces of the rats fed Y, whereas Streptoccus thermophilus was found in the feces of the LcYFM group. In HF rats, fecal concentration of Bifidobacteria was greater in the LcFM group than in the others. beta-Glucuronidase (EC 3.2.1.31) activity was lower in rats fed LcFM and Y than in those fed M and LcYFM, whereas beta-galactosidase (3.2.1.23), alpha-glucosidase (EC 3.2.1 20) and beta-glucosidase (EC 3.2.1.21) activities were higher in the LcYFM group compared with the others. Methane excretion was higher in rats fed Y than in other groups. Cecal SCFA concentrations did not differ in LcFM, Y and M groups, but total SCFA, acetate, propionate and butyrate were significantly greater in the LcYFM group. These results suggest that milk fermented with the combination of L. casei and yogurt starters leads to specific effects that are different from the simple addition of the effects found with yogurt and milk fermented with L. casei. These specific effects are potentially beneficial to human health.     

Analogs of thyrotropin-releasing hormone using an aminoglycine-based template

Novel thyrotropin-releasing hormone (TRH, pGlu-His-Pro-NH2) analogs, made by solid phase, were derived from the general scaffold pGlu-(D/L)Agl(X)-Pro-NH2 where Agl = aminoglycine. Analogs ranged from X being a proton to an acylating agent derived from substituted (aromatic heterocyclic rings) formic or acetic acids or an aminotriazolyl moiety (3'-amino-1H-1',2',4'-triazolyl) built on N(alpha) of aminoglycine or Nbeta of alpha,beta-diaminoproprionic acid (Dpr). X was expected to mimic the electronic and structural characteristics of the imidazole ring of histidine. Analogs were purified by HPLC, characterized by mass spectrometry and isolated as either diastereoisomeric mixtures or pure isomers. Analogs, tested for their binding affinity to mouse pituitary TRH receptors, have apparent equilibrium inhibitory constants > 1 microM.     

Dental sealants: prevalence and need in U.S. military recruits

From February to June in 1996, there were 47,800 students for health examination in Taichung City, Taiwan. The population consisted of the first and fourth graders of primary schools and the first grader of junior high schools. We selected 3,452 healthy students for further study by two stage sampling. In this report, 52.5% of the students were boys, and 47.5% of the students were girls. The mean age of students was 9.9 +/- 2.4 years. Girls at age 7 and age 10 had higher activity of alkaline phosphatase than boys at the same age. The peak of alkaline phosphatase activity in girls occurred at age 10. Alkaline phosphatase activity was significantly related to weight-length index by multiple regression analysis (p < 0.05). Although clinical application as an obesity factor still needs further investigation, in the future it may be well to routinely check this enzyme when assessing childhood obesity.     

Carcinoid tumor of the gallbladder

The carcinoid tumor is a relatively rare type of endocrine tumor, which arises mainly in the gastrointestinal tract. Primary gallbladder and biliary duct system carcinoids comprise less than 1% of all carcinoid tumors arising from any tissue or organ in the body. We describe a case of carcinoid tumor of the gallbladder in a 39-year-old man. There have been only 32 cases described in the literature.     

Quantitative autoradiography using a radioimager based on a multiwire proportional chamber

Determination of the biodistribution of radiopharmaceuticals is an important issue for the evaluation of their performance in diagnosis and therapy. In this study, we evaluated a digital radioimager (RI) based on a multiwire proportional chamber for quantitative autoradiography (AR). The RI allows direct detection of electronic emissions of gamma emitters. Its qualitative and quantitative performances were tested on 99mTc and (111)In labelled sections and compared with conventional film AR. Linearity of count rate versus activity was verified over a 104 range of activity. As compared with film AR, a substantial improvement of the detection limit was obtained even for acquisition periods up to 20 times less than film exposure times. We provided the basis for quantitative analysis with tissue equivalent paste standards: the 99mTc and (111)In RI counting efficiencies were respectively 1.19% and 2.35%. We illustrated the respective values of RI and film AR in two rat studies: 99mTc-DMSA in kidney and dual-isotope 99mTc-MIBI and (111)In-antimyosin in heart. Calculated activity concentrations on sections of rat organs confirmed good correlation to gamma counting (deviation less than 12%). We suggest RI as a convenient technique for fast localization of single or dual-isotope tracers and determination of activity distribution.     

Possibilities of ovum pickup in cattle

Cattle breeding has a new reproduction technique in addition to artificial insemination and embryo transfer. It is the collection of ova from living animal by means of ultrasound guided follicle aspiration (ovum pick-up), followed by embryo-production in vitro. Follicles larger than 2 mm were punctured and the ova were collected twice weekly during 3 months. In total 1677 ova were collected from ten cows; 1342 (80%) were used for in vitro maturation, fertilization, and embryoculture. All ova were fertilized with semen from one bull, and 218 transferable embryos were produced. Calculated on a year basis, this would amount to 87 embryos per animal, with an intra-animal variation between 28 and 132. This new technique may replace MOET (Multiple Ovulation and Embryo Transfer; yearly average of 25 transferable embryos per animal), if the embryo-production via OPU can be performed with semen from any selected bull.     

New protein kinase and protein phosphatase families mediate signal transduction in bacterial catabolite repression

Carbon catabolite repression (CCR) is the prototype of a signal transduction mechanism. In enteric bacteria, cAMP was considered to be the second messenger in CCR by playing a role reminiscent of its actions in eukaryotic cells. However, recent results suggest that CCR in Escherichia coli is mediated mainly by an inducer exclusion mechanism. In many Gram-positive bacteria, CCR is triggered by fructose-1,6-bisphosphate, which activates HPr kinase, presumed to be one of the most ancient serine protein kinases. We here report cloning of the Bacillus subtilis hprK and hprP genes and characterization of the encoded HPr kinase and P-Ser-HPr phosphatase. P-Ser-HPr phosphatase forms a new family of phosphatases together with bacterial phosphoglycolate phosphatase, yeast glycerol-3-phosphatase, and 2-deoxyglucose-6-phosphate phosphatase whereas HPr kinase represents a new family of protein kinases on its own. It does not contain the domain structure typical for eukaryotic protein kinases. Although up to now the HPr modifying/demodifying enzymes were thought to exist only in Gram-positive bacteria, a sequence comparison revealed that they also are present in several Gram-negative pathogenic bacteria.