Experiments on the carboxylase of pea roots

It is known that vitamin B1 is a growth factor for numerous bacteria and fungi including the yeasts (see the summary in Koser and Saunders (1938)). It has also been demonstrated that vitamin B1 is essential for the growth of the isolated roots of higher plants (Bonner, 1937; Robbins and Bartley, 1937). Because of this general vitamin B1 requirement of living organisms, it would seem a priori probable that the vitamin plays a role in some basic cellular process. That this is indeed the case was shown conclusively by the work of Peters and coworkers (see Peters and O’Brien (1938)) and of Lohmann and Schuster (1937). The latter workers found that the prosthetic group of yeast carboxylase is vitamin B1 pyrophosphate. In the case of yeast, vitamin B1 is, then, a constituent of a respiratory enzyme and vitamin B1 pyrophosphate is hence commonly referred to as “cocarboxylase,” a terminology used throughout this paper. Although considerable information is available concerning the rôle of vitamin B1 as a growth factor for roots, there is little known about the carboxylase of such roots. The present work was undertaken with the hope of elucidating possible relationships between vitamin B1 and the carboxylase of pea roots

Inhibitor specificity of amine oxidase

Although at the present time it appears clear that amine oxidase oxidation of adrenalin, or other o-diphenolic pressor amines such as were studied by Richter (6), does not play a significant physiological role, it is equally clear that the inactivation of aliphatic amines, phenethylamine and probably 4-hydroxyphenethylamine (tyramine), does predominantly take place by amine oxidase oxidation. In view of the evidence from the experiments of Ewins and Laidlaw (8) and a later study by Guggenheim and Löffler (9), such amine oxidations chiefly occur in the liver. In the present studies, an attempt was made to value quantitatively the inhibition of some of these particular type compounds by certain types of amines which are not themselves oxidized by the enzyme system (see Alles and Heegaard (10))

Substrate specificity of amine oxidase

The tyramine oxidase activity of liver extracts found by Hare (1), the aliphatic amine oxidase activity of brain, kidney, and liver extracts observed by Pugh and Quastel (2), and the adrenalin oxidase activity of similar extracts noted by Blaschko, Richter, and Schlossman (3) were brought under a common enzyme view-point by the latter authors. They were able to show (4) that extracts of brain, instestine, kindey, and liver from a number of mammals or representatives of the birds, reptiles, amphibians, and fishes all acted to absorb oxygen in the presence of several amine substrates. Hare (1) had shown that tyramine and phenethylamine form ammonia in the course of such oxidations, and Richter (5) showed that an ethylamino and a dimethylamino compound, as well as a number of methylamino and amino compounds, all yield the corresponding alkyl-amines or ammonia in the enzymic oxidation. The conslusion that the demonstrated variey of such enzymic activity can be acribed to the presence of a single type pf amine oxidase was dependent in large part on observations that the relative activities of a preparation from one source on a series of substrates bear some relation to the relative activities exhibited by a preparation from another source. Further evidence depended on the action of certain amines as inihibitors and apparent competition between substrates when two oxidizable substrates are present in the system. The degree to which relative activities of different enzyme preparations were constant in a series of substrates was not good in the data reported, and the fact that Hare (1) had not been able to note activity of the liver preparations she used upon adrenalin as the substrate appeared to require special explanations

Optimal combinations of acute phase proteins for detecting infectious disease in pigs

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KEYNOTE - D36: Personalized immunotherapy with a neoepitope vaccine, EVX-01 and pembrolizumab in advanced melanoma

Despite improvements made with checkpoint inhibitor (CPI) therapy, a need for new approaches to improve outcomes for patients with unresectable or metastatic melanoma remains. EVX-01, a personalized neoepitope vaccine, combined with pembrolizumab treatment, holds the potential to fulfill this need. Here we present the rationale and novel design behind the KEYNOTE - D36 trial: an open label, single arm, phase II trial aiming to establish the clinical proof of concept and evaluate the safety of EVX-01 in combination with pembrolizumab in CPI naive patients with unresectable or metastatic melanoma. The primary objective is to evaluate if EVX-01 improves best overall response after initial stable disease or partial response to pembrolizumab treatment, in patients with advanced melanoma. The novel end points ensure a decisive readout which may prove helpful before making major investments in phase III trials with limited phase I data. Clinical Trial Registration: NCT05309421 (ClinicalTrials.gov)

Genetic and biological characterisation of an avian-like H1N2 swine influenza virus generated by reassortment of circulating avian-like H1N1 and H3N2 subtypes in Denmark

BACKGROUND: The influenza A virus subtypes H1N1, H1N2 and H3N2 are the most prevalent subtypes in swine. In 2003, a reassorted H1N2 swine influenza virus (SIV) subtype appeared and became prevalent in Denmark. In the present study, the reassortant H1N2 subtype was characterised genetically and the infection dynamics compared to an “avian-like” H1N1 virus by an experimental infection study. METHODS: Sequence analyses were performed of the H1N2 virus. Two groups of pigs were inoculated with the reassortant H1N2 virus and an “avian-like” H1N1 virus, respectively, followed by inoculation with the opposite subtype four weeks later. Measurements of HI antibodies and acute phase proteins were performed. Nasal virus excretion and virus load in lungs were determined by real-time RT-PCR. RESULTS: The phylogenetic analysis revealed that the reassorted H1N2 virus contained a European “avian-like” H1-gene and a European “swine-like” N2-gene, thus being genetically distinct from most H1N2 viruses circulating in Europe, but similar to viruses reported in 2009/2010 in Sweden and Italy. Sequence analyses of the internal genes revealed that the reassortment probably arose between circulating Danish “avian-like” H1N1 and H3N2 SIVs. Infected pigs developed cross-reactive antibodies, and increased levels of acute phase proteins after inoculations. Pigs inoculated with H1N2 exhibited nasal virus excretion for seven days, peaking day 1 after inoculation two days earlier than H1N1 infected pigs and at a six times higher level. The difference, however, was not statistically significant. Pigs euthanized on day 4 after inoculation, had a high virus load in all lung lobes. After the second inoculation, the nasal virus excretion was minimal. There were no clinical sign except elevated body temperature under the experimental conditions. CONCLUSIONS: The “avian-like” H1N2 subtype, which has been established in the Danish pig population at least since 2003, is a reassortant between circulating swine “avian-like” H1N1 and H3N2. The Danish H1N2 has an “avian-like” H1 and differs from most other reported H1N2 viruses in Europe and North America/Asia, which have H1-genes of human or “classical-swine” origin, respectively. The variant seems, however, also to be circulating in countries like Sweden and Italy. The infection dynamics of the reassorted “avian-like” H1N2 is similar to the older “avian-like” H1N1 subtype