Improvement in Hemodynamic Responses to Metaboreflex Activation after One Year of Training in Spinal Cord Injured Humans

Spinal cord injured (SCI) individuals show an altered hemodynamic response to metaboreflex activation due to a reduced capacity to vasoconstrict the venous and arterial vessels below the level of the lesion. Exercise training was found to enhance circulating catecholamines and to improve cardiac preload and venous tone in response to exercise in SCI subjects. Therefore, training would result in enhanced diastolic function and capacity to vasoconstrict circulation. The aim of this study was to test the hypothesis that one year of training improves hemodynamic response to metaboreflex activation in these subjects. Nine SCI individuals were enrolled and underwent a metaboreflex activation test at the beginning of the study (T0) and after one year of training (T1). Hemodynamics were assessed by impedance cardiography and echocardiography at both T0 and T1. Results show that there was an increment in cardiac output response due to metaboreflex activity at T1 as compared to T0 (545.4 ± 683.9 mL · min(-1) versus 220.5 ± 745.4 mL · min(-1), P < 0.05). Moreover, ventricular filling rate response was higher at T1 than at T0. Similarly, end-diastolic volume response was increased after training. We concluded that a period of training can successfully improve hemodynamic response to muscle metaboreflex activation in SCI subjects

Mean blood pressure assessment during post-exercise: Result from two different methods of calculation

At rest the proportion between systolic and diastolic periods of the cardiac cycle is about 1/3 and 2/3 respectively. Therefore, mean blood pressure (MBP) is usually calculated with a standard formula (SF) as follows: MBP = diastolic blood pressure (DBP) + 1/3 [systolic blood pressure (SBP) – DBP]. However, during exercise this proportion is lost because of tachycardia, which shortens diastole more than systole. We analysed the difference in MBP calculation between the SF and a corrected formula (CF) which takes into account changes in the diastolic and systolic periods caused by exercise-induced tachycardia. Our hypothesis was that the SF potentially induce a systematic error in MBP assessment during recovery after exercise. Ten healthy males underwent two exercise-recovery tests on a cycle-ergometer at mild-moderate and moderate-heavy workloads. Hemodynamics and MBP were monitored for 30 minutes after exercise bouts. The main result was that the SF on average underestimated MBP by –4.1 mmHg with respect to the CF. Moreover, in the period immediately after exercise, when sustained tachycardia occurred, the difference between SF and CF was large (in the order of -20-30 mmHg). Likewise, a systematic error in systemic vascular resistance assessment was present. It was concluded that the SF introduces a substantial error in MBP estimation in the period immediately following effort. This equation should not be used in this situation

Genetic loci linked to Type 1 Diabetes and Multiple Sclerosis families in Sardinia

<p>Abstract</p> <p>Background</p> <p>The Mediterranean island of Sardinia has a strikingly high incidence of the autoimmune disorders Type 1 Diabetes (T1D) and Multiple Sclerosis (MS). Furthermore, the two diseases tend to be co-inherited in the same individuals and in the same families. These observations suggest that some unknown autoimmunity variant with relevant effect size could be fairly common in this founder population and could be detected using linkage analysis.</p> <p>Methods</p> <p>To search for T1D and MS loci as well as any that predispose to both diseases, we performed a whole genome linkage scan, sequentially genotyping 593 microsatellite marker loci in 954 individuals distributed in 175 Sardinian families. In total, 413 patients were studied; 285 with T1D, 116 with MS and 12 with both disorders. Model-free linkage analysis was performed on the genotyped samples using the Kong and Cox logarithm of odds (LOD) score statistic.</p> <p>Results</p> <p>In T1D, aside from the HLA locus, we found four regions showing a lod-score ≥1; 1p31.1, 6q26, 10q21.2 and 22q11.22. In MS we found three regions showing a lod-score ≥1; 1q42.2, 18p11.21 and 20p12.3. In the combined T1D-MS scan for shared autoimmunity loci, four regions showed a LOD >1, including 6q26, 10q21.2, 20p12.3 and 22q11.22. When we typed more markers in these intervals we obtained suggestive evidence of linkage in the T1D scan at 10q21.2 (LOD = 2.1), in the MS scan at 1q42.2 (LOD = 2.5) and at 18p11.22 (LOD = 2.6). When all T1D and MS families were analysed jointly we obtained suggestive evidence in two regions: at 10q21.1 (LOD score = 2.3) and at 20p12.3 (LOD score = 2.5).</p> <p>Conclusion</p> <p>This suggestive evidence of linkage with T1D, MS and both diseases indicates critical chromosome intervals to be followed up in downstream association studies.</p

Supernumerary chromosomes in Nephrops norvegicus L. (Crustacea, Decapoda)

Supernumerary chromosomes have been identified in the chromosome complement of Nephrops norvegicus L. by C-banding and restriction endonuclease-induced banding. These chromosomes showed peculiar features of typical B chromosomes in terms of heterochromatin content, asynapsis and distorted segregation. The presence of these chromosomes can, at least partially, account for the numerical variability already observed in this species; 2n and n values determined by counting these chromosomes separately gave a less variable number of chromosomes in the complement. Q-banding was useful to characterize some large B chromosomes with intercalary and subtelomeric bands as well as entirely positive short arms in some small submetacentric chromosomes. Nucleolar organizer regions have been identified in four pairs of chromosomes by silver staining

Studio della regione organizzatrice nucleolare in Homarus americanus (Crustacea, Decapoda)

We studied the nucleolar organizer region of Homarus americanus (crustacea, decapoda) by silver staining and chromomycin A3 banding. We found that silver labels NORs as well as kinetochores in interphase nuclei and in metaphase chromosomes

Citotassonomia degli scillaridi mediterranei (Crustacea, Decapoda).

Citotassonomia degli scillaridi mediterranei (Crustacea, Decapoda) ELISABETTA COLUCCIA, SUSANNA SALVADORI, RITA CANNAS, ANGELA MILIA, ANNA MARIA DEIANA Dipartimento di Biologia Animale ed Ecologia, Viale Poetto 1, 09126 Cagliari La famiglia Scyllaridae comprende 4 sottofamiglie e 85 specie; con le famiglie Palinuridae e Synaxidae è stata inclusa nel recente infraordine Achelata. Le informazioni sulla filogenesi di questa famiglia sono poche e si basano esclusivamente su caratteri morfologici. I dati citogenetici sui Decapodi sono scarsi ed in particolare i pochi dati disponibili sugli scillaridi riguardano solo studi preliminari. In questo lavoro presentiamo lo studio del complemento cromosomico di Scyllarus pygmaeus ed un confronto con le altre due specie mediterranee Scyllarides latus e Scyllarus arctus. Le piastre metafasiche sono state ottenute con il metodo diretto dalle gonadi e dall’epatopancreas. La localizzazione dell’eterocromatina costitutiva è stata studiata mediante bandeggio C. Nelle tre specie studiate il complemento cromosomico è costituito da alcuni grandi cromosomi e da numerosi piccoli cromosomi, prevalentemente metacentrici e submetacentrici anche se la morfologia dei cromosomi di piccola dimensione è difficile da identificare. Bande eterocromatiche sono state localizzate nelle regioni centromeriche in tutte le specie; inoltre sono presenti bande specie-specifiche. La determinazione esatta del numero cromosomico è difficile a causa della difficoltà nel conteggio di un gran numero di cromosomi e dei pochi esemplari esaminati. Per questa ragione per ogni specie viene riportato un range di valori. La citogenetica degli scillaridi è da considerarsi ancora ad uno stadio preliminare, da un primo confronto è tuttavia possibile fare alcune considerazioni: S. arctus e S. pygmaeus che appartengono alla sottofamiglia Scyllarinae presentano il numero cromosomico più basso fra gli Achelata finora studiati (70-74) mentre S. latus, unica specie studiata della sottofamiglia Arctidinae, presenta un numero cromosomico circa doppio. Questo dato indicherebbe un differenziamento fra le due sottofamiglie anche da un punto di vista cariologico