Variability of the v. cava caudalis and its tributaries in some laboratory animals. II. The laboratory rat (Rattus norvegicus v. alba).

Duplication of the v. renalis was found in 11 of the regions examined (18.3%), when it was more frequent on the right side. A v. capsularis was found in 35 regions (58.3%), usually as a single vein. There were 1-3 vv. suprarenales (but mostly two; on the right they usually joined the v. cava caudalis and on the left the v. renalis sinistra). A v. spermatica was present on the right side in every case, but on the left side in 11 cases only; in one case it was duplicated. In the rat, the v. spermatica was rather thin; if absent, it was replaced by the v. deferentialis. In nine cases (60.0%) the v. uterina cranialis dextra opened into the v. cava caudalis, while in 12 cases (80.0%) the left vein opened into the v. renalis sinistra. A v. uterina media, draining blood from the caudal third of the cornu uteri, was found in only five cases (16.7%). The v. uterina caudalis drained blood from the corpus and cervix uteri. The v. ovarica was a constant finding; it was mostly joined by the v. lumbalis--and on the left side by the v. phrenica sinistra. In males, the vv. lumbales occurred mostly as a pair of veins lying just below the vv. renales. In females, they were present on both sides. As a rule, the v. iliolumbalis occurred as a single vein on both sides. The v. cava caudalis originated at the level of the transition between the lumbar and the sacral spine, usually at the confluence of the two vv. iliacae communes, which in 14 cases (46.7%) were joined by the v. sacralis mediana. Duplication of the v. cava caudalis was found in only one case (a female). Comparison of the morphology of the v. cava caudalis and its tributaries in the rat and the guinea pig showed more slight differences between the two species

Variability of the v. cava caudalis and its tributaries in some laboratory animals. I. The guinea pig (Cavia aperea f. porcellus).

The authors studied variability of the v. caudalis and its tributaries in 30 guinea pigs (Cavia aperea f. porcellus--15 males and 15 females) after injecting the relevant venous system with blue-dyed latex. Since the largest lobe of the guinea pig's liver (the lobus sinister) is situated on the left, the right kidney lies further cranially than the left one. In males, as a rule, the right v. renalis opens into the v. cava caudalis further cranially than the left one. The number of vv. renales showed no sex-related differences, although in 17 regions (i.e. in 29%) there was more than one. The increase most often concerned the v. renalis dextra (the ratio in relation to the left vein was 15:2). The tributaries of the vv. renales are the v. spermatica or v. uterina cranialis a v. lumbalis and a v. or vv. suprarenales. There are usually two tributaries, (the commonest of which is the v. spermatica or v. uterina cranialis) on both the right and the left side, though somewhat more frequently on the left (23:19). Blood is drained from the surface or capsule of the kidney relatively often (in 75% of the cases) by the capsularis, which is the most frequent tributary of the v. spermatica or v. uterina cranialis of the corresponding side. Vv. suprarenales (1-4) are a constant finding on both sides. In males they open more often into the v. cava caudalis and in both sexes they also open into the v. renalis and v. lumbalis. The v. spermatica dextra opened into the v. renalis dextra in 10 cases and the v. spermatica sinistra into the v. renalis sinistra in 12 cases. The v. uterina cranialis dextra was a tributary of the v. renalis dextra in eight cases and the v. uterina cranialis sinistra joined the v. renalis sinistra in 13 cases. Drainage into the v. renalis can thus be regarded as the norm in both sexes and on both sides. The v. uterina caudalis leads from the corpus and cervix uteri and joins the v. uterina cranialis. It has a regular incidence and caudally it is most often a tributary of the v. iliaca communis. The v. ovarica is a constant tributary of the v. uterina cranialis; it is usually joined by several vv. lumbales or v. v. capsulares.(ABSTRACT TRUNCATED AT 400 WORDS

Origin of the v. portae and variability of its tributaries in laboratory animals. V. The golden (Syrian) hamster (Mesocricetus auratus).

The authors studied the origin and variability of the v. portae in 30 adult golden hamsters (Mesocricetus auratus) of both sexes after injecting blue-dyed latex into their portal bed. In 16 cases (53.3%) the v. portae was formed from three tributaries and in 11 cases (36.7%) from four. The v. mesenterica cranialis was the only constant tributary, the v. lienalis was a tributary in 28 cases (93.3%) and the other most frequent tributaries were the v. gastroduodenalis and the v. pancreaticoduodenalis cranialis. In one case there was an anastomosis between the v. portae and the v. cava caudalis. In 25 cases (83.3%) the v. gastrica sinistra joined the v. lienalis, in four (13.3%) it was an independent tributary of the v. portae and in one case (3.3%) it was duplicated. A v. cardiaca was found in 25 cases (83.3%), when it was most frequently a tributary of the v. gastroepiploica sinistra and v. gastrica sinistra. In one case only it was an independent tributary of the v. portae. A v. pylorica was observed in 29 cases (96.7%), usually (in 17 cases--56.7%) as a tributary of the v. gastroepiploica dextra; in three cases it was an independent tributary of the v. portae (10.0%). A v. pancreaticoduodenalis cranialis was formed in 28 cases (93.3%). In 12 cases (40.0%), together with the v. gastroepiploica dextra, it was a tributary of the v. gastroduodenalis and in eight cases (26.7%) it was an independent tributary of the v. portae. In two cases (6.7%) the two vv. pancreaticoduodenales united to form v. pancreaticoduodenalis communis. In three cases (10.0%) this vein was duplicated and in one case it was triplicated. A v. gastroepiploica dextra was found in 26 cases (86.7%) and a v. gastroepiploica sinistra in 22 (73.3%). Both veins occurred simultaneously in 19 cases (63.3%). In no case, however, was there a continuous venous arc along the curvatura major ventriculi. A v. lienalis was present in 28 cases (93.3%). It was absent in two cases (6.7%), in which it was replaced by inter-organ anastomoses with the stomach and pancreas. In 19 cases (63.3%), the v. gastroepiploica sinistra and v. gastrica sinistra were both its main tributaries and in five cases (16.7%) its main tributary was the v. gastrica sinistra. In one case the v. lienalis was duplicated. Inter-organ anastomoses were formed in all 30 cases (100%). They occurred between the spleen and the stomach in 27 cases (90%) and between the spleen and the pancreas in 28 cases (93.3%).(ABSTRACT TRUNCATED AT 400 WORDS

Involvement of fast-spiking cells in ictal sequences during spontaneous seizures in rats with chronic temporal lobe epilepsy

Epileptic seizures represent altered neuronal network dynamics, but the temporal evolution and cellular substrates of the neuronal activity patterns associated with spontaneous seizures are not fully understood. We used simultaneous recordings from multiple neurons in the hippocampus and neocortex of rats with chronic temporal lobe epilepsy to demonstrate that subsets of cells discharge in a highly stereotypical sequential pattern during ictal events, and that these stereotypical patterns were reproducible across consecutive seizures. In contrast to the canonical view that principal cell discharges dominate ictal events, the ictal sequences were predominantly composed of fast-spiking, putative inhibitory neurons, which displayed unusually strong coupling to local field potential even before seizures. The temporal evolution of activity was characterized by unique dynamics where the most correlated neuronal pairs before seizure onset displayed the largest increases in correlation strength during the seizures. These results demonstrate the selective involvement of fast spiking interneurons in structured temporal sequences during spontaneous ictal events in hippocampal and neocortical circuits in experimental models of chronic temporal lobe epilepsy

Reactivation of rate remapping in CA3

Sherpa Romeo yellow journal. Open access article. Creative Commons Attribution 4.0 International License (CC BY 4.0) appliesThe hippocampus is thought to contribute to episodic memory by creating, storing, and reactivating patterns that are unique to each experience, including different experiences that happen at the same location. Hippocampus can combine spatial and contextual/episodic information using a dual coding scheme known as “global” and “rate” remapping. Global remapping selects which set of neurons can activate at a given location. Rate remapping readjusts the firing rates of this set depending on current experience, thus expressing experience-unique patterns at each location. But can the experience-unique component be retrieved spontaneously? Whereas reactivation of recent, spatially selective patterns in hippocampus is well established, it is never perfect, raising the issue of whether the experiential component might be absent. This question is key to the hypothesis that hippocampus can assist memory consolidation by reactivating and broadcasting experience-specific “index codes” to neocortex. In CA3, global remapping exhibits attractor-like dynamics, whereas rate remapping apparently does not, leading to the hypothesis that only the former can be retrieved associatively and casting doubt on the general consolidation hypothesis. Therefore, we studied whether the rate component is reactivated spontaneously during sleep. We conducted neural ensemble recordings from CA3 while rats ran on a circular track in different directions (in different sessions) and while they slept. It was shown previously that the two directions of running result in strong rate remapping. During sleep, the most recent rate distribution was reactivated preferentially. Therefore, CA3 can retrieve patterns spontaneously that are unique to both the location and the content of recent experience.Ye

Vitamin D Pathway Genes, Diet, and Risk of Renal Cell Carcinoma

Mediated by binding to the high-affinity vitamin D receptor (VDR), vitamin D forms a heterodimer complex with the retinoid-X-receptor (RXR). Variation in both genes has been shown to modify renal cell carcinoma (RCC) risk. Therefore, we investigated whether VDR and RXRA polymorphisms modify associations between RCC risk and frequency of dietary intake of vitamin D and calcium rich foods, and occupational ultraviolet exposure among 777 RCC case and 1035 controls from Central and Eastern Europe. A positive association was observed in this population between increasing dietary intake frequency of yogurt, while an inverse association was observed with egg intake frequency. RXRA polymorphisms, located 3′ of the coding sequence, modified associations between specific vitamin D rich foods and RCC risk, while RXRA polymorphisms, located in introns 1 and 4, modified associations with specific calcium rich foods. Results suggest that variants in the RXRA gene modified the associations observed between RCC risk and calcium and vitamin D intake

Von Hippel-Lindau (VHL) inactivation in sporadic clear cell renal cancer: Associations with germline VHL polymorphisms and etiologic risk factors

Renal tumor heterogeneity studies have utilized the von Hippel-Lindau VHL gene to classify disease into molecularly defined subtypes to examine associations with etiologic risk factors and prognosis. The aim of this study was to provide a comprehensive analysis of VHL inactivation in clear cell renal tumors (ccRCC) and to evaluate relationships between VHL inactivation subgroups with renal cancer risk factors and VHL germline single nucleotide polymorphisms (SNPs). VHL genetic and epigenetic inactivation was examined among 507 sporadic RCC/470 ccRCC cases using endonuclease scanning and using bisulfite treatment and Sanger sequencing across 11 CpG sites within the VHL promoter. Case-only multivariate analyses were conducted to identify associations between alteration subtypes and risk factors. VHL inactivation, either through sequence alterations or promoter methylation in tumor DNA, was observed among 86.6% of ccRCC cases. Germline VHL SNPs and a haplotype were associated with promoter hypermethylation in tumor tissue (OR = 6.10; 95% CI: 2.28-16.35, p = 3.76E-4, p-global = 8E-5). Risk of having genetic VHL inactivation was inversely associated with smoking due to a higher proportion of wild-type ccRCC tumors [former: OR = 0.70 (0.20-1.31) and current: OR = 0.56 (0.32-0.99); P-trend = 0.04]. Alteration prevalence did not differ by histopathologic characteristics or occupational exposure to trichloroethylene. ccRCC cases with particular VHL germline polymorphisms were more likely to have VHL inactivation through promoter hypermethylation than through sequence alterations in tumor DNA, suggesting that the presence of these SNPs may represent an example of facilitated epigenetic variation (an inherited propensity towards epigenetic variation) in renal tissue. A proportion of tumors from current smokers lacked VHL alterations and may represent a biologically distinct clinical entity from inactivated cases