8-Hydroxy-PIPAT oxalate

Calcium oxalate crystal related kidney injury in a patient receiving Roux-en Y hepaticojejunostomy due to gall bladder cancer.[Pubmed:28356078]

BMC Nephrol. 2017 Mar 29;18(1):106.

BACKGROUND: Calcium oxalate nephropathy is rare in current practice. It was a common complication during jejunoileal bypass, but much less seen in modern gastric bypass surgery for morbid obesity. The major cause of it is enteric hyperoxaluria. CASE PRESENTATION: We report on a patient here with acute kidney disease due to calcium oxalate nephropathy, rather than the conditions mentioned above. The male patient received a Roux-en Y hepaticojejunostomy and common bile duct drainage. In addition to enteric hyperoxaluria, chronic kidney disease related metabolic acidosis, chronic diarrhea related volume depletion, a high oxalate and low potassium diet, long term ascorbic acid intake and long term exposure to antibiotics, all predisposed him to having oxalate nephropathy. CONCLUSION: This is the first case with such conditions and we recommend that similarly diagnosed patients avoid all these predisposing factors, in order to avoid this rare disease and its undesired outcome.

Pathogenesis of calcium oxalate urinary stone disease: species comparison of humans, dogs, and cats.[Pubmed:28361470]

Urolithiasis. 2017 Aug;45(4):329-336.

Idiopathic calcium oxalate nephrolithiasis is a highly recurrent disease that is increasing in prevalence. Decades of research have not identified effective methods to consistently prevent the formation of nephroliths or induce medical dissolution. Idiopathic calcium oxalate nephroliths form in association with renal papillary subepithelial calcium phosphate deposits called Randall's plaques (RPs). Rodent models are commonly used to experimentally induce calcium oxalate crystal and stone formation, but a rodent model that conclusively forms RPs has not been identified. Both dogs and cats form calcium oxalate uroliths that can be recurrent, but the etiopathologic mechanisms of stone formation, especially renal pathologic findings, are a relatively unexploited area of study. A large animal model that shares a similar environment to humans, along with a shorter lifespan and thus shorter time to recurrence, might provide an excellent means to study preventative and therapeutic measures, along with enhancing the concepts of the one health initiative. This review article summarizes and compares important known features of idiopathic calcium oxalate stone disease in humans, dogs, and cats, and emphasizes important knowledge gaps and areas for future study in the quest to discover a naturally occurring animal model of idiopathic calcium oxalate stone disease.

[Expression of matrix Gla protein and bone morphogenetic protein 2 in renal papillary tissues in patients with calcium oxalate kidney stones].[Pubmed:28364100]

Zhong Nan Da Xue Xue Bao Yi Xue Ban. 2017 Mar 28;42(3):277-283.

OBJECTIVE: To compare expression levels of matrix Gla protein (MGP) and bone morphogenetic protein 2 (BMP-2) in Randall's plaque of renal papillary tissues in patients with calcium oxalate kidney stones and the underlying mechanism for stone formation. Methods: A total of 30 samples of Randall's plaque in renal papillary tissues from patients with calcium oxalate kidney stones were collected from the Department of Urology of Xiangya Hospital of Central South University from April, 2015 to December, 2015 and served as an experimental group. Ten samples of renal papillary tissues in patients undergone renal tumor nephrectomy were collected from the same hospital and served as a control group. The expressions of MGP and BMP-2 mRNA and protein were detected by quantitative real-time PCR and Western blot.Meanwhile, immunohistochemical technique was used to observe the expressions of MGP and BMP-2 in different parts of renal papillary tissues in the 2 groups. Results: 1) The mRNA expression levels of MGP in the experimental group and the control group were 0.760+/-0.804 and 1.365+/-0.348, respectively, with significant difference between them (P<0.05). Them RNA levels of BMP-2 in the experimental group and the control group were 2.500+/-0.725 and 1.485+/-0.870, respectively, with significant difference between them (P<0.05). The expression levels of MGP protein in the experimental group and the control group were 0.130+/-0.424 and 0.202+/-0.704, respectively, with no significant difference between them (P>0.05). The expression levels of BMP-2 protein in the experimental group and the control group were 0.885+/-0.220 and 0.682+/-0.272, respectively, with significant difference between them (P<0.05). The immunohistochemistry showed that the protein expression of MGP in the experimental group was lower than that in the control group, while the protein expression of BMP-2 in the experimental group was higher than that in the control group (both P<0.05). Conclusion: The BMP-2 expression is increased while MGP expression is decreased in renal papillary tissues in patients with calcium oxalate kidney stones, and the formation of calcium oxalate kidney stone might be a kind of osteogenetic reaction or ectopic calcification.

The influence of citrate and oxalate on (99)Tc(VII), Cs, Np(V) and U(VI) sorption to a Savannah River Site soil.[Pubmed:28351009]

J Environ Radioact. 2017 Jun;172:130-142.

Batch sorption experiments were conducted with 0.5-50 ppb (99)Tc, (133)Cs, (237)Np and U in the presence and absence of citrate and/or oxalate in a 25 g/L Savannah River Site (SRS) soil suspension. Citrate and oxalate were the ligands of choice due to their relevancy to plant exudates, the nuclides were selected for their wide range of biogeochemical behavior, and the soil from SRS was selected as a model Department of Energy (DOE) site soil. Batch samples were continually mixed on a rotary shaker and maintained at a pH of approximately 5. Analysis via ICP-MS indicated that sorption of (237)Np increased with ligand concentration compared to baseline studies, as did sorption of (99)Tc although to a lesser extent. The increased sorption of (237)Np is proposed to be due to a combination of factors that are dependent on the ligand(s) present in the specific system including, ligand dissolution of the soil by citrate and formation of tertiary soil-oxalate-Np complexes. The increased (99)Tc sorption is attributed to the dissolution of the soil by the ligands, leading to an increase in the number of available sorption sites for (99)Tc. Uranium sorption decreased and dissolution of native uranium was also observed with increasing ligand concentration, thought to be a result of the formation of strong U-ligand complexes remaining in the aqueous phase. The majority of these effects were observed at the highest ligand concentrations of 50 mgC/L. No notable changes were observed for the (133)Cs system which is ascribed to the minimal interaction of Cs(+) with these organic ligands.

Synthesis of (R,S)-trans-8-hydroxy-2-[N-n-propyl-N-(3'-iodo-2'-propenyl)amino]tetral in (trans-8-OH-PIPAT): a new 5-HT1A receptor ligand.[Pubmed:8230102]

J Med Chem. 1993 Oct 15;36(21):3161-5.

In order to develop tracers with higher specific activity to supplant the currently used [3H]-8-OH-DPAT [8-hydroxy-2-(N,N-di-n-propylamino)tetralin] for in vitro and in vivo evaluation of 5-HT1A receptors, a new radioiodinated ligand was prepared. (R,S)-trans-8- Hydroxy-2-[N-n-propyl-N-(3'-iodo-2'-propenyl)amino]tetralin (trans-8-OH-PIPAT), 8, was synthesized by a 10-step reaction. Binding studies with rat hippocampal membrane homogenates showed that 8 exhibited a Ki value of 0.92 nM against (R,S)-[3H]-8-OH-DPAT. Radiolabeled [125I]-8 was prepared from the corresponding tri-n-butyltin precursor via an oxidative iododestannylation reaction with sodium [125I]iodide. Binding studies in the hippocampal homogenates revealed that [125I]-8 bound to a single high-affinity site (Kd = 0.38 +/- 0.03 nM,Bmax = 310 +/- 20 fmol/mg of protein). Competition binding experiments clearly indicated that the new ligand displayed the expected 5-HT1A receptor binding profile. The rank order of potency was (R,S)-trans-8-OH-PIPAT > (R,S)- 8-OH-DPAT > WB4101 > 5-HT > (R,S)-trans-7-OH-PIPAT > (R,S)-7-OH-DPAT > (R,S)-propranolol > spiperone >> ketanserin >> dopamine > atropine. This new ligand offers several unique advantages, including high specific activity, high binding affinity, and low nonspecific binding, all of which make it an excellent probe for the investigation and characterization of 5-HT1A receptors.