Reproductive and neonatal outcomes in captive bred baboons (Papio hamadryas)

Abstract: Baboons are widely used in biomedical research. Although it is widely held that Papio hamadryas breed well in captivity, each established colony has a different reproductive success often hypothesised to be due to husbandry practices. The National Baboon Colony in Australia is a unique colony that houses Papio hamadryas to mimic that structure seen in the wild. In this article; we have analysed their reproductive parameters and neonatal outcomes. The success of the colony husbandry practices was demonstrated by lack of maternal mortality, low foetal morbidity, and known maternal and paternal linage.     

Principles and practices of medicine

The medical textbooks in our university library present ‘principles’ as the basis which underlies medical ‘practice’. In this article it is argued that this helps different medical logics to co-exist. The example analyzed is that of anemia in the Netherlands. Currently this is defined pathophysiologically, statistically and clinically. These three definitions are intertwined with different strategies for the creation of normal hemoglobin levels and the detection of patients with anemia. The discrepancies between them, however, do not lead to the controversies that might be expected by those who believe in consistency. Instead, the rhetoric of principles-and-practice helps to bring about peaceful co-existence.     

Prevalence and trends of common mental disorders from 2007-2009 to 2019-2022: results from the Netherlands Mental Health Survey and Incidence Studies (NEMESIS), including comparison of prevalence rates before vs. during the COVID-19 pandemic

Up-to-date information on the prevalence and trends of common mental disorders is relevant to health care policy and planning, owing to the high burden associated with these disorders. In the first wave of the third Netherlands Mental Health Survey and Incidence Study (NEMESIS-3), a nationally representative sample was interviewed face-to-face from November 2019 to March 2022 (6,194 subjects; 1,576 interviewed before and 4,618 during the COVID-19 pandemic; age range: 18-75 years). A slightly modified version of the Composite International Diagnostic Interview 3.0 was used to assess DSM-IV and DSM-5 diagnoses. Trends in 12-month prevalence rates of DSM-IV mental disorders were examined by comparing these rates between NEMESIS-3 and NEMESIS-2 (6,646 subjects; age range: 18-64 years; interviewed from November 2007 to July 2009). Lifetime DSM-5 prevalence estimates in NEMESIS-3 were 28.6% for anxiety disorders, 27.6% for mood disorders, 16.7% for substance use disorders, and 3.6% for attention-deficit/hyperactivity disorder. Over the last 12 months, prevalence rates were 15.2%, 9.8%, 7.1%, and 3.2%, respectively. No differences in 12-month prevalence rates before vs. during the COVID-19 pandemic were found (26.7% pre-pandemic vs. 25.7% during the pandemic), even after controlling for differences in socio-demographic characteristics of the respondents interviewed in these two periods. This was the case for all four disorder categories. From 2007-2009 to 2019-2022, the 12-month prevalence rate of any DSM-IV disorder significantly increased from 17.4% to 26.1%. A stronger increase in prevalence was found for students, younger adults (18-34 years) and city dwellers. These data suggest that the prevalence of mental disorders has increased in the past decade, but this is not explained by the COVID-19 pandemic. The already high mental disorder risk of young adults has particularly further increased in recent years.     

Nonlinear autoregressive analysis of the 3/s ictal electroencephalogram: implications for underlying dynamics

 In a previous study, nonlinear autoregressive (NLAR) models applied to ictal electroencephalogram (EEG) recordings in six patients revealed nonlinear signal interactions that correlated with seizure type and clinical diagnosis. Here we interpret these models from a theoretical viewpoint. Extended models with multiple nonlinear terms are employed to demonstrate the independence of nonlinear dynamical interactions identified in the ‘NLAR fingerprint’ of patients with 3/s seizure discharges. Analysis of the role of periodicity in the EEG signal reveals that the fingerprints reflect the dynamics not only of the periodic discharge itself, but also of the fluctuations of each cycle about an average waveform. A stability analysis is used to make qualitative inferences concerning the network properties of the ictal generators. Finally, the NLAR fingerprint is analyzed in the context of Volterra-Weiner theory. Received: 6 April 1994/Accepted in revised form: 18 November 1994     

Studies on conformation of soluble and immobilized enzymes using differential scanning calorimetry. 1. Thermal stability of nicotinamide adenine dinucleotide dependent dehydrogenases.

The technique of differential scanning calorimetry (DSC) has been applied to the study of temperature-induced irreversible denturation and thus to the heat stability of soluble and Sepharose-bound liver alcohol dehydrogenase (LADH, EC 1.1.1.1) and lactate dehydrogenase (LDH, EC 1.1.1.27) in the presence of various coenzymes or coenzyme fragments. The transition temperature (Ttr) of 82.5 degrees C obtained for soluble LADH was increased by 12.5 degrees C in the presence of a saturating concentration of NACH. In the presence of NAD+, Ttr increased by 8.5 degrees C, whereas ADP-ribose and AMP caused an increase in Ttr of only 2 and 1 degree C, respectively. The Ttr of 85.5 degrees C obtained for Sepharose-bound LADH was increased by about 12 degrees C after the addition of free NADH. However, when the enzyme was immobilized simultaneously with a NADH analogue (which also binds to the matrix), a broad endotherm with a Ttr of 91.5 degrees C was obtained, indicating the presence of immobilized enzyme molecules both with, and without, associated NADH. Corresponding increases in heat stability were observed for LDH in solution in the presence of NADH, NAD+, and AMP, leading to increases in Ttr from 72 to 79.5 and 74 and 73 degrees C, respectively. The addition of pyruvate and NAD+ to the enzyme to form an abortive ternary complex led to the same stabilization as that observed with NADH, attendant with a large increase in the enthalpy of transition, deltaHtr. In these studies the technique of DSC was utilized because it is applicable both to soluble and immobilized enzymes and (1) provides rapid information about Ttr and thus thermal stability of enzymes, (2) different energetic states of an enzyme molecule can be identified, and (3) an overall picture of the thermal process is rapidly obtained.     

Metal affinity precipitation of proteins carrying genetically attached polyhistidine affinity tails

In this study, galactose dehydrogenase (EC 1.1.1.48) was chosen as a prototype target protein to investigate the capability of metal affinity precipitation to facilitate the purification of genetically engineered proteins. A DNA fragment encoding five histidine residues was fused to the 3'-terminal end of the galactose dehydrogenase gene from Pseudomonas fluorescens and thereafter expressed in Escherichia coli. The additional five histidines functioned as an affinity tail and the modified enzyme could be purified using metal affinity precipitation when the metal-chelate complex with ethylene glycol-bis-(beta-aminoethyl ether) N,N,N',N'-tetra-acetic acid, EGTA(Zn)2, was added to the protein solution. The affinity tail could also be applied for the purification of the fusion protein utilising immobilised metal affinity chromatography. After purification, the pentahistidine affinity tail could be removed enzymatically by carboxypeptidase A. Furthermore, growth rate experiments demonstrated that the expression of the metal-binding affinity tail in E. coli cells enhanced the tolerance to zinc ions when added to the growth medium.     

Engineering of lactose metabolism inE. coli by introducing β-galactosidase/galactokinase fusion enzymes

Summary A series of plasmids encoding -galactosidase/galactokinase fusion proteins with connecting linkers of different lengths and properties separating the enzyme moieties were made.E. coli cells harbouring the genes for these bifunctional enzymes were grown on minimal media with lactose as carbon source in order to asses possible metabolic effects. Differences in growth rates were observed when the cells contained a scavenger enzyme, galactose dehydrogenase, competing with galactokinase for the galactose formed by -galactosidase.E. coli cells coding for fusion proteins with long linkers then reflected markedly slower growth rates.