Effect of tannins from tropical plants on methane production from ruminants: A systematic review.

Methane (CH4) is a greenhouse gas generated during the feed fermentation processes in the rumen. However, numerous studies have been conducted to determine the capacity of plant secondary metabolites to enhance ruminal fermentation and decrease CH4 production, especially those plants rich in tannins. This review conducted a descriptive analysis and meta-analysis of the use of tannin-rich plants in tropical regions to mitigate CH4 production from livestock. The aim of this study was to analyse the effect of tannins supplementation in tropical plants on CH4 production in ruminants using a meta-analytic approach and the effect on microbial population. Sources of heterogeneity were explored using a meta-regression analysis. Final database was integrated by a total of 14 trials. The 'meta' package in R statistical software was used to conduct the meta-analyses. The covariates defined a priori in the current meta-regression were inclusion level, species (sheep, beef cattle, dairy cattle, and cross-bred heifers) and plant. Results showed that supplementation with tropical plants with tannin contents have the greatest effects on CH4 mitigation . A negative relationship was observed between the level of inclusion and CH4 emission (-0.09), which means that the effect of CH4 mitigation is increasing as the level of tannin inclusion is higher. Therefore, less CH4 production will be obtained when supplementing tropical plants in the diet with a high dose of tannins.

[Usefulness of PSA-complex in the diagnosis of prostatic carcinoma]. / Utilidad del PSA-complex en el diagnóstico del carcinoma de próstata.

OBJECTIVE: Since its discovery as a marker for prostate cancer, there have been many attempts to enhance the diagnostic efficacy of the prostate specific antigen (PSA). Among these are the studies that analyze the behavior of different forms of serum PSA bound to different antiproteases, such as alpha-1-antichymotrypsin, which forms the complexed PSA (PSA-c). This study analyzed the utility of PSA-c to enhance specificity without altering sensitivity in comparison to total PSA (PSA-t). METHODS: From September 1998 to March 1999, blood samples were obtained from 96 patients that had undergone a prostate biopsy due to a suspicion of prostate cancer. PSA-c, PSA-t (Technicon Immunol system, Bayer) and PSA-c/PSA-t ratio were analyzed in these patients. RESULTS: ROC curves were plotted and the optimal cutoffs were found for which the specificity was higher for PSA-c (44.6% [CI 95%, 32-57]) versus PSA-t (35.4% [CI 95%, 25-49]) and the PSA-c/PSA-t ratio (38.5% [CI 95%, 27-51]) while maintaining a similar sensitivity index (90%). PSA-c showed similar results for other values of sensitivity. CONCLUSIONS: PSA-c was found to improve specificity in comparison to PSA-t and PSA-c/PSA-t ratio. PSA-c determination could avoid unnecessary biopsies without altering sensitivity; i.e., the same number of prostate cancers will be detected.

Long-term effect of 90Y pituitary implantation in acromegaly.

This report examines the long-term trends in GH levels and pituitary function in a group of 38 acromegalic patients who were selected insofar as we were able to follow them up for more than 10 years after a single dose of 90Y interstitial pituitary irradiation as the sole treatment. Mean serum GH had fallen from 106 to 24 mIU/l within 3-6 months and then slowly declined to 4 mIU/l after 10 years. GH levels of less than or equal to 5 mIU/l during a 50 g oral glucose tolerance test were obtained in 8% of patients at 3-6 months and in 18% at 1 year, the cumulative percentage increasing to 53% at 10, and 76% at 14 years. The percentage of patients requiring hormone replacement therapy rose from nil pre-implant to 16% by 3-6 months, and then slowly increased to 39% by 14 years. Serial coned radiographs of the pituitary fossa were available for 32 patients. By 10 years, 16 showed thickening of the dorsum sellae and/or reduction of at least one diameter by 3 mm. Concerning symptoms, all 29 patients whose GH level fell to less than or equal to 5 mIU/l showed improvements, 22 becoming asymptomatic. Seven patients with lesser falls in GH levels (from a mean of 193 to a mean of 15 mIU/l) all improved, one becoming asymptomatic. Two showed no variation. These results show that 90Y pituitary implants have a cumulative effect over the years in inducing remission and hypopituitarism in acromegalic patients, the early decline in GH levels being swifter than from other forms of irradiation.

Inhibition of photosynthetic sulfide oxidation by organic cations.

Photosynthetic sulfide oxidation by the purple sulfur bacterium Chromatium vinosum is strongly inhibited by the organic cations benzyl viologen ( BV2 +) and tetraphenylphosphonium (TPP+) at micromolar concentrations. Both are much more inhibitory at pH 8 than at pH 7. Inhibition probably results from uptake of benzyl viologen and tetraphenylphosphonium in response to an electrical potential gradient across the plasma membrane which increases in magnitude with increasing pH. Although both compounds appear to have the same mode of action, the biochemical mechanism of their inhibition remains to be determined.

Total body calcium mass in primary hyperparathyroidism and long-term changes.

The total body calcium mass of patients with primary hyperparathyroidism was measured by whole-body neutron activation analysis. Among 14 untreated patients, the calcium mass was significantly subnormal in 2. Long-term follow-up in 4 unoperated patients showed that the calcium mass remained unchanged in 3; in the 4th patient, parathyroidectomy was carried out after the 18th month of follow-up. Her total body calcium fell by 16% before operation, but was nearly regained in the following 3 years. In 1 patient followed for 32 months after parathyroidectomy, the calcium mass remained unchanged. After a follow-up in 4 additional patients for an average of 15 months, the calcium mass remained unchanged in 3, whereas the 4th showed a significant decrease 12 months after the first measurement.