http://matera.fimmg.org/Linee%20guida/Linee%20guida%20nella%20nefrolitiasi%20(ing).pdf

Guidelines on urolithiasis

Dietary influences on serum lipids and lipoproteins.

Calcium oxalate (CaOx) crystals are distributed among all taxonomic levels of photosynthetic organisms from small algae to angiosperms and giant gymnosperms. Accumulation of crystals by these organisms can be substantial. Major functions of CaOx crystal formation in plants include high-capacity calcium (Ca) regulation and protection against herbivory. Ultrastructural and developmental analyses have demonstrated that this biomineralization process is not a simple random physical-chemical precipitation of endogenously synthesized oxalic acid and environmentally derived Ca. Instead, crystals are formed in specific shapes and sizes. Genetic regulation of CaOx formation is indicated by constancy of crystal morphology within species, cell specialization, and the remarkable coordination of crystal growth and cell expansion. Using a variety of approaches, researchers have begun to unravel the exquisite control mechanisms exerted by cells specialized for CaOx formation that include the machinery for uptake and accumulation of Ca, oxalic acid biosynthetic pathways, and regulation of crystal growth.

CALCIUM OXALATE IN PLANTS: Formation and Function

Kidney stones: pathophysiology and medical management

Sperm DNA integrity is essential for the accurate transmission of genetic information. It has a highly compact and complex structure and is capable of decondensation-features that must be present in order for a spermatozoon to be considered fertile. Any form of sperm chromatin abnormalities or DNA damage may result in male infertility. In support of this conclusion, it was reported that in-vivo fecundity decreases progressively when > 30% of the spermatozoa are identified as having DNA damage. Several methods are used to assess sperm chromatin/DNA, which is considered an independent measure of sperm quality that may yield better diagnostic and prognostic approaches than standard sperm parameters (concentration, motility and morphology). The clinical significance of this assessment lies in its association not only with natural conception rates, but also with assisted reproduction success rates. Also, it has a serious impact on the offspring and is highly prognostic in the assessment of fertility in cancer patients. Therefore, screening for sperm DNA damage may provide useful information in cases of male idiopathic infertility and in those men pursuing assisted reproduction. Treatment should include methods for prevention of sperm DNA damage.

/pdf/role-of-sperm-chromatin-abnormalities-and-dna-damage-in-male-5a2riixlg7.pdf

Role of sperm chromatin abnormalities and DNA damage in male infertility

https://www.kidney-international.org/article/S0085-2538(15)47462-9/pdf

Contribution of dietary oxalate to urinary oxalate excretion

Significantly higher frequencies of renal calculi were found among the 625 parents and sibs of 106 subjects prone to calcium oxalate stone formation as compared with 576 corresponding rela...

Genetic Predisposition to Formation of Calcium Oxalate Renal Calculi

Taurine and hypotaurine levels were measured in human sperm and seminal fluid. Sperm taurine ranged from 17 nmol/mg DNA to 348 nmol/mg DNA, and hypotaurine from 0 nmol/mg DNA to 251 nmol/mg DNA. Seminal fluid contained 319 mumol/L to 1590 mumol/L of taurine, but no detectable hypotaurine. The coefficient of variation in multiple ejaculates from a single man for these components ranged from 12% for hypotaurine to 24% for seminal fluid taurine, indicating a relative constancy in their concentrations. Sperm hypotaurine content was significantly correlated with sperm morphology, sperm relative forward progression, the percentage of motile sperm, and the total number of sperm in the ejaculate. By contrast, sperm taurine content was negatively correlated with these parameters. The mean hypotaurine content of sperm from 8 fertile men was 149 +/- 92 nmol/mg DNA, four times higher than that of sperm from 9 infertile men, which was 35 +/- 19 nmol/mg DNA (P = 0.011). In contrast, the mean sperm taurine content of the fertile men was lower than that of the infertile men (83 +/- 33 nmol/mg DNA versus 168 +/- 119 nmol/mg DNA, respectively; P = 0.07). Seminal fluid taurine concentrations, however, were similar for both groups. Hypotaurine, an antioxidant, may play an important role in protecting sperm from reactive oxygen species. Higher concentrations of taurine in the sperm of infertile men suggest that accelerated oxidation of hypotaurine to taurine may accompany the observed decline in other sperm parameters.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/j.1939-4640.1992.tb00317.x

The Taurine and Hypotaurine Content of Human Semen

Dietary oxalate is currently believed to make only a minor contribution (< 20%) to urinary oxalate excretion. A recent prospective study of stone disease suggested that dietary oxalate may be a significant risk factor. This observation led us to re-evaluate the contribution of dietary oxalate to urinary oxalate excretion. Previous studies have been hampered by inaccurate food composition tables for oxalate and inadequate methods for studying intestinal oxalate absorption. This evidence as well as factors that modify oxalate absorption are reviewed. New approaches to measure food oxalate and intestinal oxalate absorption have been examined. Capillary electrophoresis appears to be well suited for the analysis of the oxalate content of food. Two individuals consumed an oxalate-free formula diet for 7 days. This diet decreased urinary oxalate excretion by an average of 67% (18.6 mg per 24 hours) compared to oxalate excretion on self-selected diets. The absence of detectable oxalate in feces by day 6 of the diet suggested that the intestinal absorption was minimal. However, an effect of the formula diet on endogenous oxalate synthesis cannot be excluded. Restoring oxalate to the formula diet increased urinary oxalate excretion and illustrates that this experimental protocol may be well-suited for studying oxalate absorption and factors that modify it. Our results suggest that the intestinal absorption of dietary oxalate makes a substantial contribution to urinary oxalate excretion and that this absorption can be modified by decreasing oxalate intake or increasing the intakes of calcium, magnesium, and fiber.

/pdf/dietary-oxalate-and-its-intestinal-absorption-3fymig5tjp.pdf

Harold O. Goodman

Papers

Contribution of dietary oxalate to urinary oxalate excretion

Genetic Predisposition to Formation of Calcium Oxalate Renal Calculi

The Taurine and Hypotaurine Content of Human Semen

Dietary oxalate and its intestinal absorption

Genetic factors in calcium oxalate stone disease.