Who is Responsible for Fission in a Free-ranging Troop of Baboons?

The study troop of chacma baboons (Papio cynocephalus ursinus) at Mkuzi Game Reserve, Zululand, South-Africa, comprised of about 76 members that split into two new troops. The events leading to this troop fission will be described and its possible causes will be discussed. Troop fission among baboons is generally attributed to the withdrawal of low-ranking females from the main group, as a result of the cost of food competition and its effect on their reproductive success. At Mkuzi, no evidence for food competition among females was recorded in terms of rank-related time spent feeding or other time—budget components, feeding-bout length, diet composition or context of female aggression. Moreover, no evidence for rank-related differential reproductive success was found in terms of inter-birth intervals or infant survival. Female mortality was, however, related to dominance rank, with circumstantial evidence suggesting that cause of mortality was predation by leopards. Rate of female disappearances, aggression levels among females, and the percentage of time they spent in proximity to other adult troop members increased after fission. Relatively short inter-birth intervals and extremely low infant mortality rate at Mkuzi resulted in a small number of receptive females at any one time, and therefore in high costs of male sexual competition as expressed in the high levels of male aggression and woundings, both reduced after fission. It is suggested that this troop fission may have been initiated by the resident males, triggered by the high cost of sexual competition, and forced on the females, who were, consequently, subjected to higher risk of predation. The troop fission was preceded by a long process of increasing tendency for sub-trooping. It was initiated by the four resident males who kept a large distance apart from each other, herded oestrous female associates away from others and were followed by other females. The females generally tended to stay close to associates, males and females. These parties were followed by the peripheral and immigrant males who had no female associates, and eventually two distinct daughter troops were formed.     

Integrated analysis of numerous heterogeneous gene expression profiles for detecting robust disease-specific biomarkers and proposing drug targets

Genome-wide expression profiling has revolutionized biomedical research; vast amounts of expression data from numerous studies of many diseases are now available. Making the best use of this resource in order to better understand disease processes and treatment remains an open challenge. In particular, disease biomarkers detected in case–control studies suffer from low reliability and are only weakly reproducible. Here, we present a systematic integrative analysis methodology to overcome these shortcomings. We assembled and manually curated more than 14 000 expression profiles spanning 48 diseases and 18 expression platforms. We show that when studying a particular disease, judicious utilization of profiles from other diseases and information on disease hierarchy improves classification quality, avoids overoptimistic evaluation of that quality, and enhances disease-specific biomarker discovery. This approach yielded specific biomarkers for 24 of the analyzed diseases. We demonstrate how to combine these biomarkers with large-scale interaction, mutation and drug target data, forming a highly valuable disease summary that suggests novel directions in disease understanding and drug repurposing. Our analysis also estimates the number of samples required to reach a desired level of biomarker stability. This methodology can greatly improve the exploitation of the mountain of expression profiles for better disease analysis.     

Electrophoretic patterns of protein synthesis and turnover in apical plasma membrane and outer bilayer of Schistosoma mansoni

Polypeptide fractions labelled with [¹⁴C]leucine and associated with fractioned inner plasma membrane and outer bilayer (envelope) from the apical double bilayer complex of the surface epithelium of the human blood fluke, Schistosoma mansoni, were analyzed by two-dimensional electrophoresis and fluorography. In contrast to the distribution of alkaline phosphatase, the polypeptide profiles of the two bilayer fractions were similar due to cross contamination between one membrane containing larger amounts of protein (inner) and the second bilayer having more heavily labelled proteins (outer bilayer). Convincing evidence for only two of 35 polypeptides could be provided for localization to the outer bilayer. These results suggest that the marker enzyme used for the inner bilayer, alkaline phosphatase, may not be homogeneously distributed in this membrane. In pulse-chase studies a correction factor for cross-contamination was derived. The rate to turnover of the polypeptide fractions was twice as fast for the outer compared to the inner membrane, this difference being consistent with the view that multilamellar bodies are the precursors of the apical double bilayer complex. Comparing the rates of surface renewal in adult and juvenile schistosomes leads to the suggestion that membrane turnover can be correlated with susceptibility to host immune effector mechanisms.     

Modelling the Persistence of Quiescent Conidia of the Entomopathogenic Hyphomycete Paecilomyces fumosoroseus Exposed to Solar Radiation

Persistence of conidia of the entomopathogenic fungus Paecilomyces fumosoroseus exposed to artificial and solar radiation at a constant temperature was studied by monitoring the ability to germinate and to form colonies (colony - forming units , CFUs) . The photic effect of radiation on each of these variables was modelled by a decreasing function of UVB irradiation ( in J m 2) . Germination ability was represented by a logistic function and viability (log CFU) by an infinitely decreasing function . Experiments carried out under artificial conditions , at three different UVB irradiances ( from 0 . 3 to 1 . 6 W m 2) , similar to those observed in nature , confirmed the adequacy of the predictor variable and of the functions chosen for describing these data . The proposed models appeared to be irradiance independent . Under solar radiation , the models were able to describe data collected on three different summer days in France (48 o 51 N , 2 o 06 E) . However , it took a greater amount of solar UVB radiation to produce the same effect as that achieved indoors . This could be explained by differences in radiation spectra . For each model , one set of parameters was sufficient for representing all three sets of data: this constitutes an initial validation of the models proposed .     

Serotonin-mediated cardiovascular responses to electrical stimulation of the raphe nuclei in the rat.

The dorsal and median raphe nuclei in rats were electrically stimulated and blood pressure and heart rate were recorded. Stimulation of each raphe nucleus caused an increase in blood pressure without affecting heart rate. The size of the increase in blood pressure depended upon the stimulus-intensity.Significant increases were already obtained with 5 sec. trains of 0.3 msec., 200 μA stimuli given at a frequency of 50 Hz. The increases in blood pressure could be obtained with electrodes within the raphe nuclei.Pretreating rats with para-chlorophenylalanine (pCPA, 100 mg/kg.day for 3 days) significantly diminished the increases in blood pressure obtained during electrical stimulation of the median raphe nucleus. However, similar pretreatment did not affect blood pressure rises induced by dorsal raphe stimulation.These data are discussed in relation to the role of central serotoninergic mechanisms in cardiovascular control.     

Preferred egg laying sites in Palmacorixa nana (Heteroptera : Corixidae)

Female Palmacorixa nana showed clear preference for wood oviposition substrates over Elodea and plexiglass in both laboratory and field experiments. Wood was chosen because of its rigidity and rough surface. These data raise the possibility that males could gain access to females by controlling localized resources.Present address: Department 0f Entomology University 0f Alberta Edmonton, Alberta, Canada T6 G 2E3Present address: Department 0f Entomology University 0f Alberta Edmonton, Alberta, Canada T6 G 2E3     

Synergistic anticancer effect of docosahexaenoic acid and isoliquiritigenin on human colorectal cancer cells through ROS-mediated regulation of the JNK and cytochrome c release

Molecular Biology Reports - A large body of research has demonstrated a synergistic anticancer effect between docosahexaenoic acid (DHA) and standard chemotherapy regimens against colorectal cancer...     

Regulatory KIR+RA+ T cells accumulate with age and are highly activated during viral respiratory disease

Severe respiratory viral infectious diseases such as influenza and COVID‐19 especially affect the older population. This is partly ascribed to diminished CD8⁺ T‐cell responses a result of aging. The phenotypical diversity of the CD8⁺ T‐cell population has made it difficult to identify the impact of aging on CD8⁺ T‐cell subsets associated with diminished CD8⁺ T‐cell responses. Here we identify a novel human CD8⁺ T‐cell subset characterized by expression of Killer‐cell Immunoglobulin‐like Receptors (KIR⁺) and CD45RA (RA⁺). These KIR⁺RA⁺ T cells accumulated with age in the blood of healthy individuals (20–82 years of age, n = 50), expressed high levels of aging‐related markers of T‐cell regulation, and were functionally capable of suppressing proliferation of other CD8⁺ T cells. Moreover, KIR⁺RA⁺ T cells were a major T‐cell subset becoming activated in older adults suffering from an acute respiratory viral infection (n = 36), including coronavirus and influenza virus infection. In addition, older adults with influenza A infection showed that higher activation status of their KIR⁺RA⁺ T cells associated with longer duration of respiratory symptoms. Together, our data indicate that KIR⁺RA⁺ T cells are a unique human T‐cell subset with regulatory properties that may explain susceptibility to viral respiratory disease at old age.