Despite its abundance in Latin America, and its remarkable ability to use tools, there are only a few myological studies on the capuchin monkey, Cebus libidinosus. In the present study, we dissected the forearm extensor muscles of six adult males and two adult females of this species. We describe these muscles and compare them with those of other primates dissected by us and by other authors. The forearm extensor muscles of Cebus monkeys are, in general, more similar to those of other platyrrhines than to distantly related taxa that use tools, such as chimpanzees and modern humans, with three main exceptions: contrary to most other platyrrhines, (1) in Cebus, chimpanzees and modern humans the extensor pollicis longus usually inserts onto Digit I, and not onto Digits I and II; (2) in Cebus the abductor pollicis longus has two separate tendons, as is the case in chimpanzees, and in modern humans (where one of these tendons is associated with a distinct belly, forming the muscle extensor pollicis brevis); (3) in Cebus, and in modern humans and chimpanzees, the extensor pollicis longus is not deeply blended with the extensor indicis. Therefore, the Cebus monkeys provide an illustrative example of how phylogenetic constrains and ecological adaptations have been combined to develop a specific myological configuration that, associated with their sophisticated neurological organization, allow them to easily navigate in their arboreal habitats and, at the same time, to finely manipulate objects in order to search for food and to prepare this food for ingestion. Anat Rec, 293:2056Rec, 293: -2070
In a rat model, anaphylactic shock is associated with inadequately low plasma AVP concentrations. For clinically relevant doses, AVP and epinephrine had comparable effects on mean arterial pressure and heart rate values, whereas, unexpectedly, terlipressin was ineffective. These results are consistent with reports in humans experiencing anaphylaxis where AVP injection restored arterial pressure.
The supraspinatus muscle is a key component of the soft tissues of the shoulder. In pronograde primates, its main function, in combination with the other rotator cuff muscles (subscapularis, infraspinatus, and teres minor), is to stabilize the glenohumeral joint, whereas in orthograde primates it functions together with the deltoid, to elevate the upper extremity in the scapular plane. To determine whether these functional differences are also reflected in the molecular biochemistry of the supraspinatus muscles involved in these different locomotor modes, we used realtime polymerase chain reaction (RT-PCR) to analyze the expression of the myosin heavy chain (MHC) isoforms in supraspinatus muscles from modern humans and 12 species of pronograde and orthograde primates. The MHC expression pattern in the supraspinatus muscle of pronograde primates was consistent with its function as a tonic and postural muscle, whereas the MHC expression pattern observed in the supraspinatus muscle of nonhuman orthograde primates was that of a muscle that emphasizes speed, strength, and less resistance to fatigue. These findings are Int J Primatol (2011) 32:931-944
Non-specific markers of inflammation such as C-reactive protein (CRP) are associated statistically with an increased risk of atherosclerosis through mechanisms that have not yet been fully elucidated. We investigated the effects of CRP on several aspects of human monocyte biology, a cell type involved in the initiation and progression of atherosclerosis. Blood monocytes isolated from healthy men and premenopausal women (n = 9/group) were exposed to purified CRP (25 microg/ml) for 12 hours. Changes in gene expression were analyzed using a custom-made array containing oligonucleotide sequences of 250 genes expressed by activated monocytes and confirmed by quantitative PCR. CRP increased significantly the expression of the cytokines interleukin (IL)-1alpha, IL-1beta and IL-6, and the chemokines GRO-alpha, GRO-beta and IL-8. CRP also displayed anti-inflammatory effects through upregulation of liver X receptor (LXR) alpha and activin receptor expression, and down-regulation of alpha 2-macroglobulin expression. Increased LXRalpha mRNA expression in both monocytes and the monocytic cell lineTHP-1 was associated with increased LXRalpha protein expression and nuclear translocation, as well as increased ABCA1 mRNA expression, a target gene of LXRalpha. Western blot analysis revealed CRP-induced nuclear translocation of NF-kappaB and activation of p42/44, MAP and Akt kinases. CRP-induced LXRalpha mRNA expression was inhibited by anti-CD64 (FcgammaRI) antibodies and by p42/44 and PI3 kinase inhibitors. This hypothesis-generating study demonstrates that CRP modulates the expression of genes that contribute to both pro- and anti-inflammatory responses in human monocytes. Among these novel anti-inflammatory effects, we show clearly that CRP activates the LXRalpha pathway.
ABSTRACT:The bronchodilator effect of deep inhalation (DI) may be assessed from the time course of respiratory system resistance (Rrs) and reactance (Xrs) measured by the forced oscillation technique at a single frequency. The aim of the study was to assess the effect of DI in the closed chest rat. Under anesthesia and mechanical ventilation, seven Brown Norway rats were given regular DI (BN-di) and six underwent continuous tidal ventilation (BN) throughout an otherwise similar methacholine (Mch) challenge protocol. Rrs and Xrs were monitored at 20 Hz and apparent respiratory system elastance (Ers) was computed from Xrs. After Mch nebulization, there was a significant increase in Rrs and Ers compared with saline. Ers, but not Rrs, decreased after the DI and BN-di were found to have lower Ers than BN. Thus, DI significantly alters Ers and its response to Mch. Computer simulations suggested reversal of increased viscoelasticity and/or inhomogeneous behavior by the DI in that model. R ecent technological progress has promoted a number of methods for the study of respiratory function in subjects that show little cooperation capability. The forced oscillation technique is used in young children to measure the mechanical impedance of the respiratory system (Zrs). An externally generated periodic flow of small amplitude is delivered at the airway opening. Excitation frequencies may range from very low (Ͻ0.5 Hz) to very high (Ͼ50 Hz). In routine pediatric practice, however, the operating range is narrower. The use of very low frequencies is limited by the breathing of the subject and the upper airway wall motion is responsible for significant artefact at higher frequencies (1,2). As a result, most of the relevant information on respiratory mechanical properties in children so far appear to have been obtained somewhere between 5 and 15 Hz (3). The use of a single excitation frequency allows tracking Zrs changes during breathing (4 -6), which is of particular interest in view of the significant time-dependent alteration in airway function that may be observed after a deep inhalation (DI) (7,8). A decrease in airway resistance after a DI is thus highly suggestive of reversal of bronchoconstriction (9 -12). Therefore, the airway response to a DI has the capability of assessing the mechanisms of airway obstruction and has recently been applied to the study of airway hyperresponsiveness in children using the forced oscillation technique (5,13,14).Whole animal experiments are potentially useful to assess mechanisms through which a DI acts on the airways and to contribute to validating the techniques used in the routine lung function laboratory. Most studies in experimental animals are performed on lung mechanics, i.e. in open-chest condition (12,15-17), which is not representative of the conditions in the pediatric respiratory function laboratory. Airway responsiveness to Mch has been shown in the Brown Norway rat (18,19), and there are few data on how respiratory mechanics may be affected by the occurrence of DI in that model...
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