Single muscle fiber adaptations to resistance training in old (>80 yr) men: evidence for limited skeletal muscle plasticity

The purpose of this study was to investigate whole muscle and single muscle fiber adaptations in very old men in response to progressive resistance training (PRT). Six healthy independently living old men (82 +/- 1 yr; range 80-86 yr, 74 +/- 4 kg) resistance-trained the knee extensors (3 sets, 10 repetitions) at approximately 70% one repetition maximum 3 days/wk for 12 wk. Whole thigh muscle cross-sectional area (CSA) was assessed before and after PRT using computed tomography (CT). Muscle biopsies were obtained from the vastus lateralis before and after the PRT program. Isolated myosin heavy chain (MHC) I and IIa single muscle fibers (n = 267; 142 pre; 125 post) were studied for diameter, peak tension, shortening velocity, and power. An additional set of isolated single muscle fibers (n = 2,215; 1,202 pre; 1,013 post) was used to identify MHC distribution. One repetition maximum knee extensor strength increased (P < 0.05) 23 +/- 4 kg (56 +/- 4 to 79 +/- 7 kg; 41%). Muscle CSA increased (P < 0.05) 3 +/- 1 cm2 (120 +/- 7 to 123 +/- 7 cm2; 2.5%). Single muscle fiber contractile function and MHC distribution were unaltered with PRT. These data indicate limited muscle plasticity at the single-muscle fiber level with a resistance-training program among the very old. The minor increases in whole muscle CSA coupled with the static nature of the myocellular profile indicate that the strength gains were primarily neurological. These data contrast typical muscle responses to resistance training in young ( approximately 20 yr) and old ( approximately 70 yr) humans and indicate that the physiological regulation of muscle remodeling is adversely modified in the oldest old.     

Occurrence of neurotrophin receptors and transmitters in the developing Xenopus gut

The ontogeny of gut innervation in the anuran amphibian Xenopus laevis was studied using immunohistochemistry on sections of whole larvae from NF stages 38-52. Immunoreactivity to acetylated tubulin confirmed the presence of nerve fibres as early as stages 38-39. Actin immunoreactivity was found at stage 41, indicating the presence of smooth muscle cells. Trk-like neurotrophin receptors were occasionally found in nerve fibres as soon as stages 38-39. Vasoactive intestinal polypeptide (VIP) and pituitary adenylate cyclase-activating peptide (PACAP) immunoreactivities coexisted in nerves innervating the gut wall from stages 40-41, and nitric oxide synthase (NOS) from stage 42. Substance P/neurokinin A (SP/NKA) occurred at stage 42. In all these cases, the first fibres were observed in the oesophagus. Calcitonin gene-related peptide (CGRP) was first observed in nerves at stage 48. In general, VIP/PACAP and NOS innervation was denser than the tachykinin innervation. In conclusion, the development of nerve fibres in the Xenopus gut is probably dependent on neurotrophins that may act via Trk-like receptors and occur before the gut wall is fully organised morphologically. Feeding in Xenopus larvae starts at NF stage 45. The study demonstrates that several of the transmitters investigated are expressed in the gut innervation (and in endocrine cells) prior to this stage.     

Sexual signaling in the European bitterling: females learn the truth by direct inspection of the resource

In many taxa females appear to base their mate choice on multipletraits. But the relative importance of different traits inmate choice has rarely been determined. Here we show that femalesof a freshwater fish, the European bitterling, Rhodeus sericeus,base their mate choice on multiple traits that differ in theirreliability as indicators of expected reproductive successand are used at different stages of the decision process. Theinitial decision to inspect a male is based on male behaviorand red coloration, whereas the final spawning decision isbased on the quality of the live unionid mussel, Anodonta anatina,that the male is defending as an oviposition site. Male traitsmay indicate which males are worth inspecting by reflectingmale quality, such as reproductive condition and genetic constitution.Male traits do not, however, reflect mussel quality, as bright males also court females vigorously toward mussels that yielda low probability of survival of the offspring. Females, onthe other hand, are choosier than males in their choice ofspawning site and seem to gain reliable information about thesurvival probability of the eggs by inspecting the mussel directly.     

Social influences and cardiovascular risk factors as determinants of plasma fibrinogen concentration in a general population sample of middle aged men.

OBJECTIVE--To analyse the relation between fibrinogen concentration and social class and other social factors found to be related to mortality. The results regarding cardiovascular disease are unpublished, as yet. DESIGN--Cross sectional population study. SETTING--City of Gothenburg, Sweden. SUBJECTS--639 Men from a population sample of 1016 men aged 50 in 1983. They were all employed and had no history of myocardial infarction or stroke. Fibrinogen values were available for all of them. MAIN OUTCOME MEASURE--Fibrinogen concentration in relation to socioeconomic state according to occupation, and other social influences determined as number of people in the household and scores of social activities and activities in and outside the house. RESULTS--Men with low scores for activities at home had a mean plasma fibrinogen concentration of 3.34 g/l (95% confidence interval 3.21 to 3.47), whereas those with an intermediate score had a mean concentration of 3.16 (3.00 to 3.32) g/l and those with a high score 3.02 (2.95 to 3.10) g/l. Similar inverse relations were noted for the two other activity scores and for occupational class (class 1 being unskilled and semiskilled workers and class 5 professionals and executives) and the number of people in the household. Smoking exerted a strong influence on fibrinogen concentration, the relations between fibrinogen concentration and social factors being evident only in non-smokers. The mean difference in fibrinogen value between the non-smokers with the lowest activity scores at home and those with the highest scores was 0.36 (0.19 to 0.54) g/l, and similar differences were seen for the two other activity scores. Multiple regression analyses showed smoking, body mass index, the sum of all activities (inverse relation), and diabetes to be independently associated with fibrinogen value, whereas occupational class (p = 0.81) and the number of people in the household (p = 0.09) were not. CONCLUSIONS--Psychosocial influences seem to influence the coagulation system in the body in a way that is associated with cardiovascular disease and premature death.     

‘Anthropologists Are Talking’ About Anthropology After Globalisation

Laughing and humour are of great importance to most people in their everyday life and these phenomena have attracted attention from many social thinkers. It has been noted that laughter often is provoked by something that is considered to be absurd and paradoxical. This essay focuses specifically on the meaning of laughter among Matsigenka people of the Peruvian Amazon. The paper discusses how absurdity is employed within narrative genres as a structuring principle within the specific ethos that is predominant among this people and how it serves to generate and manifest conviviality.     

Morphological and genetic variation of Fucus in the eastern Gulf of Bothnia,northern Baltic Sea

Fucus vesiculosus and F. radicans (Phaeophyceae) are important habitat-formers on rocky shores in the Bothnian Sea. While both species occur sympatrically along the entire western Bothnian Sea coast, F. radicans has been found only in the northern part of the eastern coast. According to previous studies, the two species can be distinguished based on morphology, F. radicans having narrower thalli and a bushier appearance. However, marine mapping in the eastern Bothnian Sea has revealed that high morphological variation in Fucus, partly caused by gradients in salinity and exposure, makes differentiation between the two species difficult. We studied morphological and genetic variation to find out whether the two Fucus species can be differentiated in the south-eastern Bothnian Sea, and if F. radicans occurs in the area. The study was carried out in six subareas including 350 km of coast, with a salinity gradient of 3.5–6.5 PSU, and varying wave exposure. We found a gradual change towards smaller and narrower thalli and a higher number of holdfasts in Fucus populations when moving northwards to lower salinities. Distinct Fucus morphs were often found within the study sites but the morphs were genetically differentiated only at one study site in the Skaftung subarea, suggesting the occurrence of both species. However, in the Vasa subarea the sample size for analysing genetic differentiation was low due to high clonality. In the Luvia subarea south of Skaftung, Fucus morphology corresponded to that of F. radicans in earlier studies but the population was genetically more similar to F. vesiculosus in the southern subareas. We conclude that by using only morphological characteristics it is not possible to differentiate between the two species in central and northern parts of the eastern Bothnian Sea. Based on genetic analyses, the southernmost known occurrence of F. radicans in the eastern Bothnian Sea is in Skaftung.     

Science,Knowledge and Belief. On Local Understandings of Weather and Climate Change in Amazonia

This article explores different modes of understanding such atmospheric phenomena that in English are described as ‘weather’ and ‘climate’ applying Norman Fairclough’s critical discourse analysis. In consequence, focus is not on the physical phenomena as such but on ontological differences as reflected in expressions and practices pertaining to indigenous Matsigenka people and migrants from the Andean highlands to the tropical lowlands, centring on their respective interaction both with each other and, more generally, with the social, natural and supernatural dimensions of the environment. Adhering to ideals of modernity and modern science, the Andean migrants employ the climate change discourse as an indication upon social advancement to promote and legitimize their superiority over the allegedly backward and irrational Matsigenka to whom the climate discourse makes little sense. The climate change discourse thus serves here as a means of environmental colonialism in order to turn Matsigenka people into proper citizens.     

Angelman syndrome associated with an inversion of chromosome 15q11.2q24.3.

Angelman syndrome (AS) most frequently results from large (> or = 5 Mb) de novo deletions of chromosome 15q11-q13. The deletions are exclusively of maternal origin, and a few cases of paternal uniparental disomy of chromosome 15 have been reported. The latter finding indicates that AS is caused by the absence of a maternal contribution to the imprinted 15q11-q13 region. Failure to inherit a paternal 15q11-q13 contribution results in the clinically distinct disorder of Prader-Willi syndrome. Cases of AS resulting from translocations or pericentric inversions have been observed to be associated with deletions, and there have been no confirmed reports of balanced rearrangements in AS. We report the first such case involving a paracentric inversion with a breakpoint located approximately 25 kb proximal to the reference marker D15S10. This inversion has been inherited from a phenotypically normal mother. No deletion is evident by molecular analysis in this case, by use of cloned fragments mapped to within approximately 1 kb of the inversion breakpoint. Several hypotheses are discussed to explain the relationship between the inversion and the AS phenotype.     

Transdimensional relations: on human-spirit interaction in the Amazon

Animism has been a topic of interest for some time, and several innovative approaches challenging earlier conventional perspectives have been presented. Inspired by the recent thinking on this classical anthropological subject, this article explores conceptualizations of the human-spirit, or transdimensional, relationship central to any theory on animism. Drawing on fieldwork among the Matsigenka of the tropical lowlands of southeastern Peru, conceptions of and motivations for the interaction with spirits are examined. For a society that places high moral value on equality and conviviality, the emphasis on discrimination and hierarchical relations that is prominent in many studies is inappropriate. As an alternative more congenial to the Matsigenka ethos, the article stresses the convivial qualities of sharing and mutual trust. Both these virtues play down the importance of hierarchy and discrimination allowing us to understand what motivates the Matsigenka to enter into an often arduous and demanding relationship with spirits.