Tipping the balance: theoretical interrogation of divergent extended heterolytic fragmentations.

Herein we interrogate a type of heterolytic fragmentation reaction called a 'divergent fragmentation' using density functional theory (DFT), natural bond orbital (NBO) analysis, ab initio molecular dynamics (AIMD), and external electric field (EEF) calculations. We demonstrate that substituents, electrostatic environment and non-statistical dynamic effects all influence product selectivity in reactions that involve divergent fragmentation pathways. Direct dynamics simulations reveal an unexpected post-transition state bifurcation (PTSB), and EEF calculations suggest that some transition states for divergent pathways can, in principle, be selectively stabilized if an electric field of the correct magnitude is oriented appropriately

Renal homotransplantation with venous outflow or infusion of antigen into the portal vein of dogs or pigs: Transplantation at portal site

Kidneys were transplanted in mongrel dogs so that renal venous drainage was into the portal system of the hosts. Thirty-one recipients were not treated, 11 were given one dose of 3 mg of azathioprine per kg, and 11 were given 2 mg of azathioprine per day. Survival was not statistically increased compared with that in three comparable series in which renal venous drainage was into the vena cava, nor were the histopathological findings favorably altered in the “portal” kidneys. The injection of semisoluble antigen into the portal vein at the same time as renal transplantation at the caval site, had an effect no different from that if the antigen were given systemically during caval site transplantation. The conclusion that drainage of grafts into the portal vein was not beneficial was reached in 20 pigs evenly divided between the portal and vena caval sites, and in 12 pairs of dog to pig or pig to dog xenografts. Thus, none of these experiments has identified an advantage of antigen delivery into the portal as opposed to the systemic venous system. © 1977 by The Williams & Wilkins Co

The opsonizing ligand on Salmonella typhimurium influences incorporation of specific, but not azurophil, granule constituents into neutrophil phagosomes.

Phagosomes were purified from human neutrophils ingesting Salmonella typhimurium opsonized with adsorbed normal human serum or with rabbit IgG. Constituents within the phagosome were endogenously labeled by supplying the cells with 125INa during phagocytosis. Lactoferrin and vitamin B12 binding protein (TC1 and TC3), markers for specific granules, were present in the phagosomes from neutrophils ingesting S. typhimurium opsonized with IgG but were 3.5- to 5-fold less prominent in phagosomes from cells phagocytosing Salmonella bearing C3 fragments only. In contrast, iodinated azurophilic granule components, most prominently defensins, were the major constituents in phagosomes prepared under both opsonization conditions. Furthermore, labeled complement (CR1 and CR3) and immunoglobulin (Fc gamma RIII) receptors were incorporated in the phagosome regardless of the ligand mediating phagocytosis. These results suggest that the ligand-receptor interactions mediating phagocytosis influence incorporation of neutrophil-specific granule contents into phagosomes

Portacaval shunt for glycogen storage disease and hyperlipidaemia.

Complete portacaval shunt was used to treat 10 patients with glycogen storage disease. A favourable effect was noted on body growth and a number of metabolic abnormalities. More recently, continous night feedings with an intermittently placed gastric tube or through a gastrostomy has been shown to be helpful either before or after portacaval shunts. Such alimentation techniques may eliminate the need for shunts in some patients and be of adjuvant benefit in others. Portacaval shunt was also used for three children who had homozygous Type II hyperlipidaemia. Substantial reductions in serum cholesterol concentration were observed, as well as resorption of xanthomas. Reversal of some cardiovascular lesions has been documented. The benefits of portacaval shunt in these disorders is probably due to the change in the hormone climate of the liver and the whole organism brought about by diversion of the hormone-rich splanchnic venous blood around the liver

Role of high-spin hyperon resonances in the reaction of γp→K+K+Ξ−\gamma p \to K^+ K^+ \Xi^-

The recent data taken by the CLAS Collaboration at the Thomas Jefferson National Accelerator Facility for the reaction of $\gamma p \to K^+ K^+ \Xi^-$ are reanalyzed within a relativistic meson-exchange model of hadronic interactions. The present model is an extension of the one developed in an earlier work by Nakayama, Oh, and Haberzettl [Phys. Rev. C 74, 035205 (2006)]. In particular, the role of the spin-5/2 and -7/2 hyperon resonances, which were not included in the previous model, is investigated in the present study. It is shown that the contribution of the $\Sigma(2030)$ hyperon having spin-7/2 and positive parity has a key role to bring the model predictions into a fair agreement with the measured data for the $K^+\Xi^-$ invariant mass distribution.Comment: 8 pages, 3 figures, REVTe

Stimulation of hepatic regeneration after partial hepatectomy by infusion of a cytosol extract from regenerating dog liver

A cytosol liver extract was prepared from adult dog livers and from liver remnants that had been regenerating for one, two and three days after 72 per cent partial hepatectomy. Given intraportally, the most active of these cytosols did not stimulate proliferation in the livers of normal dogs. However, infused during a six hour period into the portal vein of test group dogs, the cytosol from 48 and, especially, 72 hour regenerating livers augmented the regeneration response ordinarily produced by 44 per cent partial hepatectomy. The effect was delayed. It became identifiable 48 hours after infusion and reached a peak at 72 hours. Neither augmentation nor significant inhibition of the normal regeneration response was produced by cytosol from normal liver and 24 hour regenerating liver or by a six hour infusion of insulin. The amplification effect of active cytosol was equivocal when the infusions were given intraperitoneally and was not demonstrable at all by the intravenous route. In these investigations, it is confirmed that there are growth control factors in regenerating liver but the nature or physiologic significance of the factor or factors has not been clarified

The effect of splanchnic viscera removal upon canine liver regeneration

The influence of portal blood factors on canine liver regeneration was studied with graded nonhepatic splanchnic evisceration, coupled with 44 and 72 per cent hepatectomies. In one type of experiment, the pancreas was retained while the rest of the intra-abdominal gastrointestinal tract was removed. In a second variety, total pancreatectomy was performed with preservation of the intra-abdominal organs. In a third kind of experiment, total nonhepatic splanchnic evisceration was performed. Liver regeneration after hepatectomy was decreased by all three kinds of viscera removed as judged by deoxyribonucleic acid synthesis, autoradiography and mitotic index. Pancreatectomy and nonpancreatic splanchnic evisceration caused almost equal decreases in the regenerative response. Total nonhepatic splanchnic evisceration essentially halted regeneration during the first three postoperative days and intraportal infusions of insulin or glucagon, or both together, did not reverse this effect. The decrease in liver membrane bound adenyl cyclase activity and biphasic change in liver cyclic 3',5'-adenosine monophosphate concentrations normally seen partial hepatectomy was disrupted after the various eviscerations. Adenyl cyclase activity and cyclic monophosphate concentrations tended to be higher than normal in the eviscerated dogs. These observations provide more support for our previously proposed hypothesis that control of liver regeneration is by multiple factors. Pancreatic hormones are important modifiers of this response but by no means exercise exclusive control. Other substances of gastrointestinal origin, presumably including hormones and nutrient supply apparently play important specific roles. The volume of portal flow is a secondary and nonspecific, but possibly significant, factor

Nitric Oxide Bioavailability and Its Potential Relevance to the Variation in Susceptibility to the Renal and Vascular Complications in Patients With Type 2 Diabetes

OBJECTIVE—We compared the renal and systemic vascular (renovascular) response to a reduction of bioavailable nitric oxide (NO) in type 2 diabetic patients without nephropathy and of African and Caucasian heritage. RESEARCH DESIGN AND METHODS—Under euglycemic conditions, renal blood flow was determined by a constant infusion of paraminohippurate and changes in blood pressure and renal vascular resistance estimated before and after an infusion of l-Ng-monomethyl-l-arginine. RESULTS—In the African-heritage group, there was a significant fall in renal blood flow (Δ−46.0 ml/min per 1.73 m(2); P < 0.05) and rise in systolic blood pressure (Δ10.0 mmHg [95% CI 2.3–17.9]; P = 0.017), which correlated with an increase in renal vascular resistance (r(2) = 0.77; P = 0.004). CONCLUSIONS—The renal vasoconstrictive response associated with NO synthase inhibition in this study may be of relevance to the observed vulnerability to renal injury in patients of African heritage