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Tubular aggregates (TAs) have been identified with a number of myopathies in humans. Periodic paralysis and muscle pain are frequently associated with TAs. Very little is known about the functional and anatomical significance of TAs in myopathic and aging human muscle. Recently, animal models for TAs have been identified which suggested that TAs are gender specific. However, recent studies suggest a need for more controls.

Qualitative microscopic analysis of muscle architecture provides information about cellular markers of muscle fiber disruption in myopathic, aging, and experimentally damaged muscle. However, this approach does not provide sensitive information regarding the extent of muscle damage and has serious limitations when research protocols address tissue remodeling. The purpose of this study was to quantitatively assess the extent of muscle damage in young and older adults before and after exercise-induced damage. The older adults in this study had lower aerobic capacities and muscle mass than their younger counterparts, suggesting greater vulnerability toward muscle damage produced by physiologic stress.Five young males, ages 20 to 29 years and five older males, age 60 to 75 years had percutaneous needle biopsies taken from the vastis lateralis muscle before and after (N=9) exercise consisting of reverse cycling or downhill treadmill running at a prescribed physiologic effort. Muscle samples were prefixed in 3.0% gluteraldehyde in cacodylate buffer and post-fixed in VL OSO4. This was followed by routine procedures for TEM.

Plasma creatine kinase (CK) activity has often been used as a marker of exercise-induced skeletal muscle damage. While the pattern of muscle damage following eccentric exercise has been established in young adults, there is little data available on eccentric exercise-induced muscle damage in

The nuclear DNA or DNP differences in hydrolysis resistance are utilized here as an indication of the greater or lesser complexity of DNA-protein bindings, possibly related to the degree of heterochromatinization. They have been studied with the Feulgen reaction in lymphocytes of peripheral blood smears of Cercopithecus aethiops aethiops (Primates) (a species in which adaptive evolution still appears to be under way) and of Rhinolophus ferrumequinum (Microchiroptera), a representative of an older group of Mammals, Chiroptera, which is considered as evolutionarily established at least since the Eocene period (Simpson, 1945). These species have a very different “genome size” (recorded as Feulgen-DNA nuclear content): the percent ratio is at least 130:100 (Capanna & Manfredi Romanini, 1971) . From the comparison between the two hydrolysis curves it appears that their general shape is similar and that the height differences are constant for each hydrolysis time, with the exception of the first peak which is operationally defined as the acid labile fraction of DNA. This peak is higher in C. aethiops aethiops than in R. ferrumequinum. Both curves fall short of characteristic platform (120 min — 360 min) of “acid resistant” DNA, which is constantly recorded in Homo and tentatively attributed to some particular DNA-protein link (depolymerization peak of Anderson et al., 1971, 1975). No qualitative difference is remarkable in the DNA protein ratio, which could be relied to heterochromatinization materials, or to a selective loss of heterochromatic fractions of chromatin. We are therefore lead to interpret the present data as a verisimilar indication that Chiroptera ancient specialization is ascribable to a mechanism of evolutionary loss which, unlike the actual microevolution of some species of Mammals, could not be preceded by a selective heterochromatinization.

Nuclear DNA contents were estimated by microdensitometry in five species ofAkodon rodents:Adodon molinae, A. dolores, A. mollis, A. azarae, Bolomys obscurus) and in three chromosomal varieties ofA. molinae (2n=42; 2n=43, 2n=22). The data obtained showed that the species with the highest DNA content wasB. obscurus, followed in order of decreasing genome size byA. molinae, A. mollis, A. dolores andA. azarae. InA. molinae the forms with 2n=42 chromosomes had the lowest and the forms with 2n=44 the highest amount of DNA, while the forms with 2n=43 had intermediate DNA contents. The variation in DNA amount detected inA. molinae was interpreted as a phenomenon of amplification occurring in the chromosomal areas involved in the chromosomal rearrangement giving rise to the polymorphism exhibited by this species. The DNA contents of shared chromosomes (chromosomes with similar size, morphology and G banding pattern, which are found in two or more phylogenetically related species), were compared and correlated with values of total nuclear DNA. The information obtained indicates that: (a) shared chromosomes have variable amounts of DNA: (b) in a given species there is a correlation between the amount of nuclear and chromosomal DNA in most shared chromosomes (and perhaps in most of the chromosmal complement), e.g., the higher the amount of nuclear DNA, the higher the content of DNA in shared chromosomes; (c) some chromosomes may undergo processes of amplification or deletion restricted to certain regions and usually related with mechanisms of chromosomal rearrangements. The data obtained seem to indicate that the genome size of a species depends on the interaction of two independent mechanisms: (1) a general process of DNA variation which acts coincidentally in the same direction (gain or loss) in the whole chromosome complement without disturbing the mechanism of chromosome condensation producing G bands and (2) restricted processes of DNA variations (amplifications or deletions) which act on single chromosomes and which are in most cases related with chromosmal rearrangements.

The fate of morphologically normal but chromosomally abnormal spermatozoa derived from mice with variable degrees and complexity of Robertsonian heterozygosity was studied at different sites along the male and female genital tract by Feulgen-DNA measurements. In addition, the percentage frequencies of morphologically abnormal spermatozoa in transit along the male and female genital tracts were studied. It was found that during transit from the epididymis to the vas deferens the distribution of the Feulgen-DNA contents of morphologically normal spermatozoa changed: Spermatozoa with chromatin with the extremely low or high Feulgen staining intensity disappeared. The percentages of morphologically abnormal sperm cells did not change at these levels. In the female genital tracts, the distribution of Feulgen-DNA content of morphologically normal spermatozoa did not show significant changes. This indicates that spermatozoa are able to reach the fallopian tube in spite of gross genome unbalance. There is evidence that unbalanced spermatozoa take part in the fertilization process, producing abnormal zygotes subject to postzygotic loss. Conversely morphologically abnormal spermatozoa were preferentially lost before they reached the fallopian tube, suggesting they had been eliminated prezygotically.

SUMMARYIn the planarian species, Dugesia lugubris, two biotypes are found: E (2n = 8, n = 4) and F (2n = 6, n = 3); on the basis of karyometric studies it has been hypothesized that the second was derived from the first through a Robert-sonian mechanism of centric fusion. The quantitative cytochemical data reported here confirm the hypothesis of karyotype evolution, since there are no significant differences between the DNA content of the nucleus in the two biotypes. The regenerative blastemas of both biotypes contain a number of cellular populations with a variable Feulgen-DNA content; these correspond to successive doublings of the 2C diploid content. In addition, metaphase plates with multistranded chromosomes have been found. A difference between the chromosome C-banding in the two biotypes has also been observed.

The purpose of this study was to assess the relationship between physiological and anthropometrical variables and 15-km time trial (TT) cycling performance time. Twenty-two competitive cyclists averaged 59.7 ml · kg–1 · min–1 for maximal oxygen consumption ([Vdot]O2max), 42.8 ml · kg–1 · min–1 for anaerobic threshold (AT), and 23.5 min for the 15 km TT race. The relationship between [Vdot]O2max and cycling performance time was r = – 0.68, (p < .01) while the correlation between AT and performance time was r = – 0.93, (p

In brief: This study investigated the effects of a ten-week cardiac rehabilitation program on selected coronary heart disease (CHD) and blood clotting risk factors in 14 cardiac patients. Comparisons of before and after program values showed a significant reduction in body weight, diastolic blood pressure, and triglyceride concentration. Mileage covered per exercise session increased significantly. Serum cholesterol, systolic blood pressure, and resting heart rate values showed moderate but nonsignificant positive changes. Results of this study suggest that ten weeks of cardiac rehabilitation can enhance certain CHD risk factors while reducing others. However, a cardiac patient may require years of rehabilitation with careful attention to diet and medication to effectively reduce risk factors.

The urinary androstanediol was determined in cases of idiopatic hirsutism by means of GLC. The determination was carried out on urines of 9 women before the beginning of a treatment with placebo and after three and six months of estrogen treatment. The initial range of values was between 39 and 99 μg/24h; at the end of the treatment the values ranged between 13 and 25 μg/24 h. The yield of the whole procedure of determination was 70% and the detection limit was about 0.2 μg of androstanediol in urine.

The early symptoms of brain dysfunction in infants born to heroin-addicted mothers were studied during the first month of life by a multimethod approach. Neurological examination and polygraphic EEG studies of sleep patterns were performed; concomitantly plasma levels of beta-endorphin and met-enkephalin were measured. Whenever possible, these parameters were correlated with each other and with the severity of the withdrawal syndrome. While the neurological examination of addicted newborns was almost negative, altered sleep cycles with a decrease in active sleep and an increase in quiet sleep were noted together with a marked increase in the plasma concentration of the endogenous opioid peptides. Furthermore, instead of reverting to the adult values (as for normal babies), the peptides remained at high levels up to the 40th day of life.

The influence of chromosome variability on the production of euploid spermatozoa was investigated in a suitable biological model, the Akodon molinae system. This consists of individuals whose chromosome constitution is 2n = 42, 2n = 43, or 2n = 44. The only difference between these three karyotypes occurs through a Robertsonian rearrangement combined with two pericentric inversions. Thus, the animals with 2n = 42 (simple homozygotes or SH) have two large metacentric chromosomes number 1; animals with 2n = 43 (heterozygotes or Ht) have a chromosome 1 and two subterminal chromosomes la and lb homologues of the long and short arms of the chromosome 1, respectively; animals with 2n = 44 (double homozygotes or DH) have a pair of la and a pair of lb chromosomes. The gametic euploidy frequency correlated with each chromosome constitution was evaluated on the basis of the DNA content of spermatozoa, which was determined microdensitometrically after the Feulgen reaction, taking into account the site of the spermatozoa along the male genital tract. A comparative assessment of gametic aneuploidy frequency in caput epididymis versus vas deferens demonstrated (1) a falloff in euploid production in passing from the 2n = 42 to the 2n = 44 chromosome forms, alongside a high degree of intragroup variability, and (2) a lower aneuploidy frequency in the vas deferens than in caput epididymis in all the forms considered. These two features, taken together with similar results in the mouse chromosome variability system, suggest that a selection mechanism is operative against aneuploid spermatozoa in the epididymis. This finding is of interest in a wider perspective, since it might turn out to be valid for many mammals.

In brief: Sixty-four third-grade children participated in a ten-month (September to June), four-day-a-week fitness program (ten minutes of stretching and strength development exercises followed by 12 minutes of running). A control group of 45 children was allowed free play during this time. In June the experimental group completed a 1,600-meter run significantly faster than the control group. In the experimental group, boys had significantly greater improvements than girls. Exercise heart rates expressed as a percentage of predicted maximal heart rate showed no significant changes in control subjects, but in the experimental group, girls had increases from 73.7% to 80.5% and boys from 73.1% to 87.7% of maximal heart rate.

This study explores the effects of two types of fixative on chromatin. The first type (acrolein, glutaraldehyde) engenders a high degree of ultrastructural preservation. The other type are fixatives that are widely used in cytochemistry and cytogenetics (acetic acid, 3:1 by vol. methanol-acetic acid, methanol alone, formaldehyde). Lymphocytes of adult rats so-fixed in vitro were prepared for electron microscopy or microdensitometric evaluations of smears. Assessments were made of variations in their total protein, nuclear basic protein and DNA contents. DNA was determined both as Feulgen-positive material and by its binding of intercalating dyes (Methyl Green, specific for double-stranded polynucleotides). Our results showed that some fixatives break up the chromatin organization by acting on particular components of chromatin fibres. They can thus be considered to be destructive agents in situ. In addition, a revaluation of some aldehyde fixatives is proposed for both ultrastructural and cytochemical research.

To assess the effects of a group resistance exercise program on prepubescent children, an experimental group of boys (n = 26) and girls (n = 24), with a mean age of 8.4 ± 0.5 years, participated in 12 weeks of school based training. The program consisted of upper body exercise using hand-held weights, stretch tubing, balls, and self-supported movements. A control group of boys (n = 30) and girls (n = 16), mean age 8.6 ± 0.5 years, had a free-play period. Boys were significantly stronger than girls on all initial strength evaluations and were taller and had lesser skinfold sums. ANCOVA was used to evaluate pre/post changes in cable tensiometer elbow flexion and extension, right and left handgrip strength, pull-ups, flexed arm hang, sit-ups, sit-and-reach flexibility, and body composition parameters. Following the training period, significantly greater gains were made by the experimental group for right handgrip, flexed arm hang, pull-ups, and flexibility. Greater decreases in sum of skinfolds were also found. Training responses of boys and girls were similar. It was concluded that a group strength training program can be an effective means of increasing fitness levels and improving body composition in both boys and girls of this age.

Genome size was measured as the amount of Feul-gen-stained DNA in six species of the family Hylobatidae and in a hybrid of the gibbon (Hylobates muelleri) and siamang (Symphalangus syndactylus). The family, on the whole, exhibits a wider range of genome sizes than pongids; in particular, the siamang has about 15% more DNA than the 44-chromosome Hylobates species of the “lar” group. Quantitative analysis of C-heterochromatin in hybrid metaphases showed that the difference in genome size of the parental species correlates with the amount of C-band-positive material. Hylobatids are the only group of primates in which karyotype diversification has taken place with a massive quantitative change in constitutive heterochromatin.

Resume Des recherches preliminaires indiquent l'existence de lipides dans la cellule glandulaire gastrique de 23 especes d'oiseaux. Dans le developpement du poulet et du pigeon les lipides sont demonstrables des le commencement de l'alimentation.

The purpose of this study was to elucidate the mechanics of rising on the toes: a topic which has been controversial for more than a century. A new instrumentation for determination of the location of the gravitational line was developed. Instead of spring scales it employed strain gauges, connected with an oscillograph which automatically recorded, on paper, changes in the partial weight of the subject. The instant of heel rise was also automatically recorded. Subjects were tested barefoot, and in wooden sandals with a knife edge attached near the front end. Each test was repeated 10 times. Electrical stimulation of the calf muscles of a man in standing position caused a backward fall, indicating that these muscles do not lift the heels; and, therefore, a lever of the second class is not involved. Instead, the muscles that cause dorsiflexion of the feet contract and shift the center of gravity over the fulcrum (the metatarsal heads) and lift the heels. This is a function of a first class lever. ...

(1971). Dna Nuclear Content in Lymphocytes from Mus Musculus L. and Mus Poschiavinus Fatio. Bollettino di zoologia: Vol. 38, No. 3, pp. 321-326.

Summary The Author analyzes the possible contribution of histochemistry to comparative anatomy. The general problems of orientation and management of this kind of research work are considered. As examples of anatomical comparative work on histochemical basis a number of subjects regarding the tegumental and digestive 9ystem and the blood are mentioned, taking into consideration the work carried out in the Institute. Two tables are presented: the first concerning the distribution in vertebrates of typical enterochromaffine and silverstaining preen-terochmaffine cells; the second concerning blood cells. The opportunities of the comparative method in histochemical work, which allows to connect different data in a more general view of the problems are discussed.

A conclusione di una vasta ricerca istochimica compiuta sulla corda dorsale diLampetra planeri adulto e allo stadio diAmmocoetes al massimo di accrescimento l'A. ha potuto dimostrare: a) la presenza di glicogeno nelle cellule cordali; b) la presenza di un mucopolisaccaride e di una proteina in rapporti abbastanza costanti (probabilmente costituenti un complesso mucoproteico) nel citoplasma delle cellule dello strato epiteliomorfo, nella guaina fibrosa e nella lamina interna della guaina elastica; c) 1'esistenza di gradienti di concentrazione di sostanza secca sia all'interno del tessuto cordoide propriamente detto, sia nello spessore delle guaine.

Summary The results obtained histophotometrically on the nuclear content of DNA of erythrocytes in 20 different 6pecies of. Cypriuidae are presented and discussed as to the possible existence of cases of polyploidism in the famili of Cypriuidae.

Resume L'A. analyse les possibles interpretations du fait que, dans la cellule glandnlaire gastrique des vertebres non mammiferes, il y a presque constamment des lipides soit alcohol solubles que alcohol resistents. Ces lipides peuvent etre compares aux lipides alcohol resistents des cellules delomorphes et aux gouttes lipidiques alcohol solubles des cellules adelomorphes.

Genome sizes of the planariansD. lugubris (2n=8),D. polychroa (2n=8) andD. benazzii (2n=16) were evaluated on metaphase plates by measuring both the Feulgen-DNA contents and the karyotype lengths. In the three species, genome sizes are significantly different; this finding rules out the possibility of a karyotype evolution through simple chromosome rearrangements betweenD. lugubris andD. polychroa. A different Feulgen-DNA content per unit length of karyotype in the three species studied was also found, which suggests that DNA could be differently packed along metaphase chromosomes.