Relationship between velocity and muscular endurance of the upper body.

Strength, power and muscular endurance tests have been developed as means of assessing people's physical abilities. However, testing may be expensive or time consuming. A method to reduce the time of physical assessment could be to use predictive algorithms for indirect assessment. The aim of this study will be to determine a relationship between strength, power and muscular endurance in order to identify predictors for an easier and faster assessment. 33 male strength-trained participants (22.8 ±â€¯4.6 years, 172.5 ±â€¯6.7 cm, 68.0 ±â€¯10.6 kg) performed a single pull-up (SPU) and a single push-up (SPH) and a set of pull-ups (EPU) and push-ups (EPH) to exhaustion. The participants were divided into three sub-groups according to their training experience. Force(F), Power(P), Velocity(V) and relative power(R-P), extracted from an accelerometer (500 Hz), were compared between groups (ANOVA) and a subsequent linear regression analysis was performed to identify predictors of the performance measures. The regression models were able to explain 61% of the variance with the EPU as dependent variable and the V of the SPU as independent variable and 68% of the variance with the EPH as dependent variable and EPU as independent variable. In addition, increased performance measures were found according to training experience, in particular regarding muscular endurance of both the EPU and EPH (p < 0.001 and p < 0.01, respectively). A significant effect of training experience was also present for the V of the SPU (p < 0.001). The results indicate that a relation between muscular endurance and velocity is present. The generated equations allow to estimate both the number of EPH and EPU from a SPU. The equations may be helpful to reduce the time of assessment for upper body physical evaluation.

Influence of a sport-specific training background on vertical jumping and throwing performance in young female basketball and volleyball players.

AIM: The purpose of this study was to evaluate the influence of 3 years of sport-specific training background (SSTB) on vertical jumping and throwing performance in young female basketball and volleyball players. METHODS: Thirty-one healthy adolescent girls, of which 11 age-matched control subjects [C], 10 basketballers (BP) and 10 volleyballers (VP) participated to the study. The throwing performance was assessed by seated backward overhead ball throw (SBOMBT) and seated chest pass throw (SCPT) using a 3-kg rubber medicine ball. Instead, the vertical jumping performance was evaluated by squat jump (SJ) and countermovement jump with (CMJ-AS) and without arm swing (CMJ) using Optojump system (Microgate srl, Italy). RESULTS: During SJ and CMJ with and without arm swing VP group showed a higher vertical jump performance than BP and C ones. In particular we showed that VP exhibited a higher flight time and jump height than C (P<0.05) in SJ, CMJ and CMJ-AS tests. Players showed higher performances than C in SCPT and SBOMBT. However, we found only a significant difference (P<0.05) in the comparison between BP and C during SCPT. Moreover, we found significant correlations between SBOBMT performances and CMJ-AS jump heights in C (r= 0.60; p= 0.02) and VP (r= 0.81; p<0.01) groups compared to BP one (r= -0.47; p= 0.08). CONCLUSION: These data suggest that 3 years of SSTB might be able to promote significant neuromuscular adaptations in volleyball and basketball athletes' maximal power compared to age-matched control subjects.

Influence of family history of NIDDM on basal metabolic rate in sedentary and active women.

AIM AND METHODS: The influence of family history of non-insulin-dependent diabetes (NIDDM) on basal metabolic rate (BMR) has been investigated in 116 voluntarily women: 25 sedentary and 34 athletes without a family predisposition to type 2 diabetes (FH-); 21 sedentary and 15 athletes with a second degree predisposition to NIDDM (FH+); 10 sedentary and 11 athletes with a first degree predisposition to NIDDM (FH++). RESULTS: The results showed that family history on type 2 diabetes is strongly related to sedentary in women with significant high body weight values and an increased fat mass. There was no significant difference in the body parameters among the athletes groups, confirming the protective role of regular physical activity on these parameters. Analysing basal energy expenditure showed that sedentary FH++ women had a significant increase in BMR in absolute values; however there were no differences in BMR when reported to body weight and body fat-free mass. In contrast, the FH++ athletes group had lower BMR (absolute values) than the sedentary group. No differences were found in the relative BMR either. By comparing the recorded BMR of the groups with the theoretical values, it has been shown that the FH++ athletes had a reduced increase in BMR with respect to the other groups. The FH- athletes showed a higher energy turnover compared to the other women and relative to predicted values. CONCLUSION: This study confirms that family history of type 2 diabetes has an important influence on the phenotype of women and it can be associated with significant metabolic and anthropometric modifications in young healthy subjects. It may also account for changes in the body composition and basal metabolic rate alterations in subjects with a predisposition to type 2 diabetes, by reducing the metabolic basal output expected in active subjects.

The effects of indoor cycling training in sedentary overweight women.

AIM: The aim of this study was to evaluate the body composition and physiological effects in young sedentary overweight women after an indoor cycle training period. METHODS: Fourteen subjects (22.6+/-2.1 yrs; 25-29.9 BMI) were trained for 12 weeks in a specific indoor cycling protocol (ICP) consisting of three sessions/week carried out in a fitness room. Body composition and physiological parameters were taken before the beginning of the study and after 12, 24 and 36 sessions. RESULTS: We observed a reduction of 2.6% and 3.2% in body weight and of 4.3% and 5% in fat mass after 24 and 36 sessions respectively (P<0.05). Lean mass increased by 2.3% and 2.6% respectively after 24 and 36 sessions. Body circumferences diminished in response to ICP. Resting heart rate decreased by 6.5% and 9% respectively after 24 and 36 sessions. After the tenth week, we found a reduction of 11 beats.min-1 in average training heart rate, an increase of 0.5 mL/kg-1.min-1 in average training oxygen uptake and an increase of 8.6 Watts in average power output. Moreover, an increase in cardio-respiratory fitness was observed (37.1+/-4.3 vs. 40.2+/-4.6 mL/kg-1.min-1) after 36 sessions. CONCLUSION: The decrease in body weight, without any restriction on food consumption, and the improvement in cardio-respiratory fitness suggests that ICP may be efficient for losing weight and preventing the increased risk of cardiovascular disease in young overweight women. Indoor cycling can be performed by young sedentary overweight women; however, it is fundamental to formulate training protocols which are intensity and length specific to the fitness level of the participants.

Structural analysis of rat patellar tendon in response to resistance and endurance training.

Little is known about tendon adaptations induced by mechanical loading. Our goal was to evaluate the effects of two different exercise training protocols on adult rat patellar tendon. Ninety-six male Wistar rats were divided into a sedentary group (control), a resistance-trained group and an endurance-trained group. The examinations were performed after 15, 30 and 45 days of training and after 2 weeks of rest since training was stopped. The content of collagen fibers and the cell nuclei number were quantified on tendon cross sections. In order to assess the training effectiveness, we evaluated the heart/body weight ratio, which was higher in 45 day-trained rats than their controls (P<0.01), showing the presence of cardiac hypertrophy. An increase in the content of collagen fibers was observed in the 45 day-trained groups and after 2 weeks of rest in the endurance group. Moreover, both trained groups showed a decrease in cell nuclei number after 30 and 45 days of training and 2 weeks of rest (P<0.05). Endurance and resistance training induces a tendon tissue remodeling that depends on the length and intensity of workload rather than the training type. Further studies are necessary to evaluate whether these structural modifications are associated with an increase in the mechanical strength of tendon.

Upon oxidative stress, the antiapoptotic Hsp60/procaspase-3 complex persists in mucoepidermoid carcinoma cells.

Hsp60, a mitochondrial chaperonin highly conserved during evolution, has been found elevated in the cytosol of cancer cells, both in vivo and in vitro, but its role in determining apoptosis during oxidative stress (OS) has not yet been fully elucidated. The aim of the present work was to study the effects of OS on Hsp60 levels and its interactions with procaspase- 3 (p-C3) and p53 in tumor cells. NCI-H292 (mucoepidermoid carcinoma) cells were exposed to various concentrations of hydrogen peroxide (H2O2) for 24 hours. Cell viability was determined by Trypan blue and MTT assays. DNA damage was assessed by the Comet assay, and apoptosis was measured by the AnnexinV cytofluorimetric test. Exposure to increasing concentrations of H2O2 resulted in a reduction of cell viability, DNA damage, and early apoptotic phenomena. Hsp60, p-C3, p53, and p21 were assessed by Western blotting and immunocytochemistry before and after OS. Hsp60 and p-C3 were present before and after OS induction. Immunoprecipitation experiments showed an Hsp60/p-C3 complex before OS that persisted after it, while an Hsp60/p53 complex was not detected in either condition. The presence of wild type (wt) p53 was confirmed by RT-PCR, and p21 detection suggested p53 activation after OS. We postulate that, although OS may induce early apoptosis in NCI-H292 cells, Hsp60 exerts an anti-apoptotic effect in these cells and, by extension, it may do so in other cancer cells.

Increased expression of titin in mouse gastrocnemius muscle in response to an endurance-training program.

Titin, a sarcomeric giant protein, plays crucial roles in muscle assembly, elasticity and stability. Little is known about titin adaptation to endurance exercise. We studied the effects of endurance training on titin expression in mouse gastrocnemius muscles (MGM). Sixty-three ten-week-old male Swiss mice were divided into seven groups. Four groups were composed of untrained control animals (C0, C15, C30, C45) instead the other three included mice trained for 15 (T15), 30 (T30) and 45 (T45) days by treadmill. The training protocol was mainly aerobic, characterized by moderate-intensity, rhythmic and continuous exercises. Titin expression was determined by immunohistochemistry on MGM sections. Results revealed a significant reduction in body weight of the T45 mice and a significant increase in titin expression (% titin immunoreactivity median [range] = 41.11 [20-60] vs. 30.00 [10-50]). It is postulated that the up-regulation of titin expression is an adaptative mechanism to increase muscle elasticity and stability in response to the high number of stretch-shorten cycles during endurance training. Such a mechanism may be important for minimizing muscle energy consumption and improving performance during running.

Adult stem cells: the real root into the embryo?

During embryonic development, a pool of cells may become a reserve of undifferentiated cells, the embryo-stolen adult stem cells (ESASC). ESASC may be responsible for adult tissue homeostasis, as well as disease development. Transdifferentiation is a sort of reprogramming of ESASC from one germ layer-derived tissue towards another. Transdifferentiation has been described to take place from mesoderm to ectodermal- or endodermal-derived tissues and viceversa but not from ectodermal- to endodermal-derived tissues. We hypothesise that two different populations of ESASC could exist, the first ecto/mesoblast-committed and the second endo/mesoblast-committed. If confirmed, this hypothesis could lead to new studies on the molecular mechanisms of cell differentiation and to a better understanding of the pathogenesis of a number of diseases.

Increased cx43 and angiogenesis in exercised mouse hearts.

Several studies focused on the macroscopic architecture of increased cardiac wall induced by exercise training. Our goal was to evaluate myocardiocyte, interstitial and vascular component, and connexin-43 expression in endurance-trained mouse hearts. Sixty-three 10-week-old male Swiss mice were divided into four sedentary groups (C0, C15, C30 and C45) and three groups exercised respectively for 15 (T15-D; running intensity [RI]: 3.18 m/min; running duration [RD]: 75 min/first week and 150 min/second week), 30 (T30-D; RI: 3.96 m/min; RD: 150 min/third week and 225 min/fourth week) and 45 days (T45-D; RI: 3.96 m/min and 4.8 m/min, respectively for the fifth and sixth week; RD: 300 min) on a treadmill. Morphometric analyses were performed to quantify myocardiocyte size and number, and the capillary and interstitial connective tissue (ICT) area. We assessed the expression of ventricle myosin light chain-II, vimentin and connexin-43 by western blot analyses. Our results showed a hypertrophy of the interventricular septum and left ventricle in T30-D and T45-D mice that was not due to variations in myofibrillar content, myocardiocyte size and number, or ICT quantity but to a significant increase in the capillary area. The microvascular remodeling was associated with vimentin increased expression in ICT cells and connexin-43 upregulation. The first phenomenon might be related to an enhanced request of remodeling and growth factors; the second suggests a new role of connexin-43 in cardiac angiogenesis.

Research of cardiomyocyte precursors in adult rat heart.

Recent reports supported the existence of stem cells in adult hearts. However, phenotype and localization of these cells have not been completely described and it is unknown if cardiac regenerative potential differs from one subject to another. The aims of our work were to identify different populations of cardiac stem cells by the analysis of specific markers and to evaluate the expression variability of these markers in 12 adult rat hearts. The expression of CD9, taube nuss and nanog suggests the presence of stem cells from the earliest stages of embryogenesis in adult myocardium. Their different expression could be associated to the degree of stem cell differentiation. CD34 and c-Kit antibodies were used to detect stem cells committed to one or more specific tissue lineages and we found a strong immunoreactivity for CD34 exclusively in the endothelial cells and a low positivity for c-Kit in the interstitium and next to the vessels. Moreover, as c-Kit expression highly differed within all examined hearts, we suggest that cardiomyogenic potential is different among the various subjects. Undifferentiated cells with myogenic-committed phenotype expressing GATA-4 and nestin were found, respectively, in the interstitial and myocardial cells and in few interstitial cells. Therefore, the physiologic turn over of cardiomyocytes may occur in adult hearts as it has been shown in many others organs. The study of myogenic potential could be important to identify markers specific of stem cells in in vivo adult myocardium that may be used to purify these cells and evaluate their regenerative ability.

60KDa chaperonin (HSP60) is over-expressed during colorectal carcinogenesis.

The aim of the present study was to evaluate the expression of the heat shock protein 60 (HSP60), a mitochondrial matrix-associated protein belonging to the chaperonin family, in colorectal adenomas and cancers, comparing them to normal colonic tissues and hyperplastic polyps. We performed both immunohistochemistry and Western blot analysis for HSP60. Immunohistochemistry resulted positive in all tubular adenomas and infiltrating adenocarcinomas. By contrast, normal tissues and hyperplastic polyps were negative. Quantitative analysis showed that tubular adenomas with different levels of dysplasia did not present statistical differences concerning HSP60 positivity. In addition, carcinomas always showed the highest expression. Western blot analysis confirmed these observations. These data suggest that HSP60 over-expression is an early event in carcinogenesis. We suspect that HSP60 plays a different role in colorectal carcinogenesis with respect to that in normal cells, which foresees its possible use as diagnostic and prognostic tools.

Presence of atrial natriuretic factor in normal and hyperplastic human prostate and its relationship with oxytocin localisation.

In this work, we showed the presence of atrial natriuretic factor (ANF) in human prostate and compared its localisation in normal and hyperplastic conditions. ANF was localised in epithelial and stromal cells, being increased in hyperplasia, mainly in the stromal component. Moreover, we compared ANF and oxytocin positivity in the same glands, focusing on the possible relationship between the paracrine effects of these two hormones.

Defective apoptosis and tumorigenesis: role of p53 mutation and Fas/FasL system dysregulation.

The transcription factor p53 and the cytokine receptor FasL are two of the most famous regulators of cell life, and their alterations can cause a large number of pathologies, including cancer. In this review, we focused on how they can determine defective apoptosis, one of the causes of tumorigenesis and tumor progression. The importance of this knowledge lies in the new perspectives that gene therapy can offer to cure cancer.

Expression of 60-kD heat shock protein increases during carcinogenesis in the uterine exocervix.

OBJECTIVES: The aim of the present study was to determine the presence and expression of the 60-kD heat shock protein (HSP60) in the dysplasia-carcinoma sequence in the uterine exocervix and to evaluate its diagnostic and prognostic significance. METHODS AND RESULTS: We performed Western blot and immunohistochemical analyses on biopsies from 40 cases, consisting of 10 normal exocervical biopsies, 10 low-grade squamous intraepithelial lesions (L-SIL), 10 high-grade squamous intraepithelial lesions (H-SIL) and 10 cancerous exocervices (G2 grade). The immunohistochemical results were quantified by computer-assisted image analysis. Western blot analysis showed that HSP60 was undetectable in normal tissues and that there was a gradual increase of protein expression from L-SIL to carcinoma. Immunostaining for HSP60 was negative in normal tissue and positive in basal and parabasal layers of L-SIL epithelium; H-SIL were markedly stained in all layers of epithelium, and carcinomas showed an even stronger positivity. The increasing expression correlated with the malignancy grade. Finally, koilocytes were mostly negative in L-SIL and positive in H-SIL. CONCLUSIONS: The increasing degree of expression of HSP60 from L-SIL to carcinoma and the different intraepithelial distribution between L-SIL and H-SIL could be used as a new diagnostic tool. Moreover, HSP60 could have a role in cervical carcinogenesis.

Protective role of the complement regulatory protein human CD-55 in cardiac xenograft: a descriptive study and a revision of the literature.

The limited and inadequate availability of organs from human donors has resulted in the utilisation of xenografts as an alternative tool. Nevertheless, hyperacute rejection (HAR) following xenograft determines the loss of the transplanted organ. The "primum movens" is the activation of the complement pathway mediated by the binding of natural xenogenic antibodies to the endothelium of the graft, followed by the lysis of the endothelial cells with subsequent oedema, thrombosis and necrosis of the transplanted organ. In this work we describe morphological and biomolecular observations of isolated human-decay accelerating factor (h-DAF, CD55) transgenic pig hearts, after perfusion for four hours with human blood. H-DAF is a membrane glycoprotein inhibiting the complement activation in humans. We describe considerably reduced damages in transgenic hearts, compared to controls. The cardiac function resulted preserved. Our data are in agreement with what was already shown by other groups using different experimental models. In conclusion, we encourage the use of new sources of transgenic animals, pointing out the importance of morphological analysis in evaluation of xenograft.

The hypothalamic magnocellular neurosecretory system in developing rats.

Studies concerning the development of the magnocellular system are scarce and discordant in literature. We carried out an immunohistochemical study on supraotic and paraventricular hypothalamic nuclei using antivasopressin and antioxytocin antibodies in developing rats between the 15th day of intrauterine life and the 6th day of postnatal life. In addition, we performed RT-PCR experiments to establish the stage at which these hormones appear and neurosecretory activity commences. The results showed that supraoptic and paraventricular nuclei appear, respectively, on the 16th and the 18th day of intrauterine life and both immediately synthetize vasopressin neurohormone. By contrast, synthesis of oxytocin takes place from the 2nd day after birth. Probably, these nuclei synthetize oxytocin in conjunction with the decline of placental maternal oxytocin.

Poorly differentiated synovial sarcoma: a case report.

Poorly differentiated synovial sarcoma is a rare soft tissue tumor. We studied a case arising in the pleural cavity of a young subject, characterised by the presence of spindle cell, small cell, and large epithelioid cell areas. We performed stains for mucosubstances and analysed the expression of cytokeratins 5/6, 7, 8, 18, 19, CEA, CD34, Ber-Ep4 and calretinin to characterize the phenotype of this neoplasm. We furthermore assessed immunohistochemically the presence of p53, Bcl-2, Bax and caspase 3, four apoptotic markers, to evaluate a relationship between apoptotic activity and the behaviour of this tumor. Our findings showed a strong presence of calretinin, p53 and Bcl-2 in all three areas. The possibility that poorly differentiated synovial sarcoma could be calretinin-positive was a new data, to our knowledge, and it could be of some importance in diagnostic pathology. Moreover, the negligible positivity for Bax and caspase 3 suggested that the minor role of programmed cell death could be one of the causes of the aggressive behaviour of this tumor. These data also suggest that the reduction of apoptotic phenomena in poorly differentiated synovial sarcoma could be considered one of the major mechanisms of tumoral growth.

Study of axillary lymph node asymmetry in a female population.

We analysed a large series of axillary lymph nodes, with and without metastases following radical mastectomy for breast cancer. We found left/right asymmetry in numbers of lymph nodes, and also asymmetry of lymph node dimensions, which could have been the caused by tumoral antigenic stimulation. The distribution of hyperplastic node patterns differed significantly.

3'-untranslated regions of oxidative phosphorylation mRNAs function in vivo as enhancers of translation.

Recent findings have indicated that the 3'-untranslated region (3'-UTR) of the mRNA encoding the beta-catalytic subunit of the mitochondrial H(+)-ATP synthase has an in vitro translation-enhancing activity (TEA) [Izquierdo and Cuezva, Mol. Cell. Biol. (1997) 17, 5255-5268; Izquierdo and Cuezva, Biochem. J. (2000) 346, 849-855]. In the present work, we have expressed chimaeric plasmids that encode mRNA variants of green fluorescent protein in normal rat kidney and liver clone 9 cells to determine whether the 3'-UTRs of nuclear-encoded mRNAs involved in the biogenesis of mitochondria have an intrinsic TEA. TEA is found in the 3'-UTR of the mRNAs encoding the alpha- and beta-subunits of the rat H(+)-ATP synthase complex, as well as in subunit IV of cytochrome c oxidase. No TEA is present in the 3'-UTR of the somatic mRNA encoding rat mitochondrial transcription factor A. Interestingly, the TEA of the 3'-UTR of mRNAs of oxidative phosphorylation is different, depending upon the cell type analysed. These data provide the first in vivo evidence of a novel cell-specific mechanism for the control of the translation of mRNAs required in mitochondrial function.

Specific neurons of brain cortex and cerebellum are PIPPin positive.

We recently cloned a cDNA encoding an RNA-binding protein, that we called PIPPin, which is highly enriched in the rat brain and contains two putative double stranded RNA-binding domains (PIP1 and PIP2) and a central cold shock domain (CSD). Here we report that PIPPin is specifically enriched in some pyramidal neurons of the cerebral cortex and in the Purkinje cells of the cerebellum. We also show that PIPPin inhibits translation of H1(o) and H3.3 mRNA in a cell-free system. The results reported suggest that PIPPin down-regulates histone variant expression in the developing rat brain.