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C Capelli

Publications and source records attributed to C Capelli.

At least 37 records · Page 2Linked to original sources
PubMed2000

Effects of different after-loads and knee angles on maximal explosive power of the lower limbs in humans.

Maximal explosive power during two-leg jumps was measured on four sedentary subjects [mean age 43.0 (SD 10.3) years, mean height 1.74 (SD 0.04) m, mean body mass 73.5 (SD 1.3) kg] using a sledge apparatus with which both force and speed could be directly measured. Different after-loads were obtained by positioning the sledge at five different angles (SA, alpha) in respect to the horizontal so that m x g x sin alpha (where m is the sum of body mass and the mass of the sledge seat, g the acceleration due to gravity) decreased (on average) from 78% body mass at 30 degrees to 27% body mass at 10 degrees, thus simulating conditions of low gravity. The subjects were asked to jump maximally, without counter movement, starting from 70 degrees, 90 degrees, 110 degrees, and 140 degrees of knee angle (KA); the protocol being repeated at 10 degrees, 15 degrees, 20 degrees, 25 degrees and 30 degrees SA. The average (W+(mean)) power output during concentric exercise (CE) was found to decrease when the starting KA was increased, but to be unaffected by SA (i.e. by the after-load, the simulated low g). The higher values of W+(mean) were recorded at 90 degrees KA [15.01 (SD 1.46) W x kg(-1), average for all subjects at all SA]. The subjects were also asked to perform counter movement (CMJ) and rebound jumps (RE) at the same SA as for CE. In CMJ and RE maximal power outputs were also found to be unaffected by the SA; W+(mean) amounted to 16.03 (SD 0.28) W x kg(-1) in CMJ and 16.88 (SD 0.36) W x kg(-1) in RE (average for all subjects at all SA). In CE, CMJ and RE, the instantaneous force at the onset of the positive speed phase (F(i)) was found to increase linearly with SA (i.e. with increasing m x g x sin alpha), and the difference between F(i) in CMJ or RE and F(i) in CE (F(i) in CMJ minus F(i) in CE and F(i) in RE minus F(i) in CE) was unaffected by SA. This indicated that both maximal power and the elastic recoil were unaffected by simulated low g ranging from 1.71 m x s(-2) (at 10 degrees SA) to 4.91 m x s(-2) (at 30 degrees SA).

Adult↗
PubMed2000

Energy cost and mechanical efficiency of riding a four-wheeled, human-powered, recumbent vehicle.

Oxygen consumption at steady state ( VO2, l x min(-1)) and mechanical power (W, W) were measured in five subjects riding a human-powered vehicle (HPV, the Karbyk, a four-wheeled recumbent cycle) on a flat concrete road at constant sub-maximal speeds. The external mechanical work spent per unit of distance (W, J x m(-1)), as calculated from the ratio of W to the speed (v, m x s(-1)), was found to increase with the square of v: W = 8.12 + (0.262 x v2) (r = 0.986, n = 31), where the first term represents the mechanical energy wasted, over a unit of distance, against frictional forces (rolling resistance, Rr), and the second term (k x v2) is the work performed, per unit distance, to overcome the air drag. The rolling coefficient (Cr, obtained dividing Rr by m x g, where m is the overall mass and g is the acceleration of gravity) amounted to [mean (SD)] 0.0084 (0.0008), that is about 60% higher than that of a racing bicycle. The drag coefficient was calculated from the measured values of k, air density (p) and frontal area (A) [Cx = k x (0.5 x A x rho)-1], and amounted to 1.067 (0.029), that is about 20% higher than that of a racing bicycle. The energy cost of riding the HPV (Ck, J x m(-1)) was measured from the ratio of metabolic power above rest (net VO2, expressed in J x s(-1)) to the speed (v, m x s(-1)); the value of this parameter increased with the square of v, as described by: Ck = 61.45 + (0.675 x v(2)) (r = 0.711, n = 23). The net mechanical efficiency (eta) was calculated from the ratio of W to Ck: over the investigated speed range this turned out to be 0.22 (0.021). Best performance times (BPTs) of a "typical" elite athlete riding the Karbyk were calculated over the distances of 1, 5 and 10 km: these were about 8% longer than the BPTs calculated, on the same subjects, when riding a conventional racing bicycle.

Adult↗
PubMed2000

Energy cost of front-crawl swimming at supra-maximal speeds and underwater torque in young swimmers.

The energy cost of front-crawl swimming (Cs, kJ x m(-1)) at maximal voluntary speeds over distances of 50, 100, 200 and 400 m, and the underwater torque (T') were assessed in nine young swimmers (three males and six females; 12-17 years old). Cs was calculated from the ratio of the total metabolic energy (Es, kJ) spent to the distance covered. Es was estimated as the sum of the energy derived from alactic (AnA1), lactic (AnL) and aerobic (Aer) processes. In turn, AnL was obtained from the net increase of lactate concentration after exercise, AnA1 was assumed to amount to 0.393 kJ x kg(-1) of body mass, and Aer was estimated from the maximal aerobic power of the subject. Maximal oxygen consumption was calculated by means of the back-extrapolation technique from the oxygen consumption kinetics recorded during recovery after a 400-m maximal trial. Underwater torque (T' x N x m), defined as the product of the force with which the feet of a subject lying horizontally in water tends to sink times the distance from the feet to the center of volume of the lungs, was determined by means of an underwater balance. Cs (kJ x m(-1)) turned out to be a continuous function of the speed (v, m x s(-1)) in both males (Cs = 0.603 x 10(0.228v), r2 =0.991; n = 12) and females (Cs = 0.360 x 10(0.339r), r2 = 0.919; n = 24). A significant relationship was found between T' and Cs at 1.2 m x s(-1); Cs = 0.042T' + 0.594, r = 0.839, n = 10, P<0.05. On the contrary, no significant relationships were found between Cs and T' at faster speeds (1.4 and 1.6 m x s(-1)). This suggests that T' is a determinant of Cs only at speeds comparable to that maintained by the subjects over the longest, 400-m distance [mean (SD) 1.20 (0.07) m x s(-1)].

Adolescent↗
PubMed2000

Effects of 17 days bedrest on the maximal voluntary isometric torque and neuromuscular activation of the plantar and dorsal flexors of the ankle.

Maximal voluntary isometric torque values of the ankle plantar (Tim,PF) and dorsal flexors (Tim,DF) were assessed in eight healthy adult males at 5 degrees and 15 degrees of dorsal flexion (DF) and at 5 degrees, 15 degrees and 25 degrees of plantar flexion (PF) with the knee at right angles, before (two times), during (three times) and after (three times) 17 days of 6 degrees head-down tilt bedrest (BR). Integrated electromyograms (iEMG) were also recorded from the gastrocnemius medialis and tibialis anterior. Tim,PF and the iEMG of the gastrocnemius medialis were significantly larger (by 14% and by 27%, respectively) at the end of recovery than before BR. This was probably the consequence of training and/or habituation leading to: (1) increased activation of the plantar flexors; and (2) decreased co-activation of the antagonist muscles. Neither Tim,DF nor the tibialis anterior iEMG changed significantly. The effects of BR on muscle performance were evaluated as follows. The net torque generated by a given muscle group was assumed to be the algebraic sum of the torque generated by the agonists and by the antagonists. Thus, for the plantar flexors Tim,PF = alpha iEMGGm - beta iEMGTa, where: (1) iEMGGm and iEMGTa are the iEMGs of gastrocnemius medialis and of tibialis anterior during maximal PF; and (2) the constants alpha and beta represent the electromechanical coupling of the plantar (alpha) and dorsal (beta) flexors. Similarly for the dorsal flexors: Tim,DF = beta iEMGTa - alpha iEMGGm, where iEMGTa and iEMGGm are the iEMGs of tibialis anterior and gastrocnemius medialis during maximal DF. Torque and iEMG values were assessed for all subjects under all experimental conditions. Thus, since the biomechanical leverage of the system was constant, alpha and beta could be calculated. During BR, alpha decreased by 25% and it dropped by a further 30% during recovery. In contrast, beta remained almost unchanged. This suggests that, in spite of training and/or habituation, BR significantly impaired the maximal isometric performance of the plantar flexors, an effect that continued during the initial 10 days of recovery.

Adult↗
PubMed2000

Inferring microevolutionary patterns from allele-size frequency distributions of minisatellite loci: a worldwide study of the APOB 3' hypervariable region polymorphism.

The availability of numerous population and molecular data makes the apolipoprotein B 3' hypervariable region (APOB 3' HVR) polymorphism ideal for a pilot study of the relationships between the allele-size frequency distributions (referred to as allele-size distributions) of minisatellite loci and the microevolutionary processes underlying their present-day polymorphism in human populations. In this paper, we present a worldwide APOB 3' HVR study, based on published and unpublished data, which refers to 36 populations. We systematically compare APOB 3' HVR within-group diversity (in terms of heterozygosity, number of alleles, and allele-size variance) in numerous human populations, including African, European, Asian, Amerindian, Australomelanesian, and Polynesian groups. Overall, our analyses indicate a greater APOB 3' HVR diversity in Africans than non-Africans. Then, we compare APOB 3' HVR allele-size distributions. The APOB 3' HVR allele-size distribution is found to be quasi-unimodal in Africans and bimodal or nonunimodal in non-African populations. The analysis of the distribution of pairwise comparisons suggests that Africans expanded earlier and/or that their ancestral population was larger than other continental groups. As a final step, we examine APOB 3' HVR interpopulational relationships by using three genetic distances. The F(ST) genetic distance, which assumes genetic drift as being the agent that differentiates populations, provides results that are more congruent with established anthropological knowledge than mutation-based distances (D(SW) and R(ST)). We hypothesize that the ancestral population was characterized by a high heterozygosity, an extended range of allele size, and a quasi-unimodal allele-size distribution centered on allele *37, features persisting in examined African populations. Sampling processes during "out-of-Africa" migrations would be responsible for the decrease in APOB 3' HVR gene diversity and the nonunimodal allele-size distribution observed in non-Africans. Some possible confounding factors are discussed and a prospect of how the hypothesis could be refined and tested is given.

Apolipoproteins B↗
PubMed1999

Physiological determinants of best performances in human locomotion.

In human locomotion, the metabolic power required (E) to cover a given distance d, in the time t is set by the product of the energy cost of the locomotion (C), i.e. the amount of metabolic energy spent to move over one unit of distance, and the speed (v = d t(-1)): E = Cv = Cdt(-1). Since, for any given d, v is a decreasing function of t and C is either constant or increases with v, it necessarily follows that E is larger the smaller the value of t. Thus, for any given distance and subject, the shortest time will be achieved when E is equal to the individual maximal metabolic power (Emax). In turn, Emax is a decreasing function of t: it depends upon the subject's maximal aerobic power (MAP) and on the maximal amount of energy derived from the full utilisation of anaerobic energy stores (AnS). So, if the relationship between C and (v) in the locomotion at stake and the subject's MAP and AnS are known, his best performance time (BPT) over any given distance can be obtained by solving the equality Emax(t) = E(t). This approach has been applied to estimate individual BPTs in running and cycling. In this paper, the above approach will be used to quantify the role of C, MAP, and AnS in determining BPTs for running, track cycling and swimming. This has been achieved by calculating the changes in BPT obtained when each variable, or a combination thereof, is changed by a given percentage. The results show that in all the three types of locomotion, regardless of the speed, the changes in BPT brought about by changes of C alone account for 45-55% of the changes obtained when all three variables (C, MAP and AnS) are changed by the same amount.

Adult↗
PubMed1999

Nuclear DNA sequences from late Pleistocene megafauna.

We report the retrieval and characterization of multi- and single-copy nuclear DNA sequences from Alaskan and Siberian mammoths (Mammuthus primigenius). In addition, a nuclear copy of a mitochondrial gene was recovered. Furthermore, a 13,000-year-old ground sloth and a 33,000-year-old cave bear yielded multicopy nuclear DNA sequences. Thus, multicopy and single-copy genes can be analyzed from Pleistocene faunal remains. The results also show that under some circumstances, nucleotide sequence differences between alleles found within one individual can be distinguished from DNA sequence variation caused by postmortem DNA damage. The nuclear sequences retrieved from the mammoths suggest that mammoths were more similar to Asian elephants than to African elephants.

Animals↗
PubMed1999

Effects of microgravity on maximal power of lower limbs during very short efforts in humans.

The maximal power of the lower limbs was determined in four astronauts (age 37-53 yr) 1) during maximal pushes of approximately 250 ms on force platforms ["maximal explosive power" (MEP)] or 2) during all-out bouts of 6-7 s on an isokinetic cycloergometer [pedal frequency 1 Hz: maximal cycling power (MCP)]. The measurements were done before and immediately after spaceflights of 31-180 days. Before flight, peak and mean values were 3.18 +/- 0.38 and 1.5 +/- 0. 13 (SD) kW for MEP and 1.17 +/- 0.12 and 0.68 +/- 0.08 kW for MCP, respectively. After reentry, MEP was reduced to 67% after 31 days and to 45% after 180 days. MCP decreased less, attaining approximately 75% of preflight level, regardless of the flight duration. The recovery of MCP was essentially complete 2 wk after reentry, whereas that of MEP was slower, a complete recovery occurring after an estimated time close to that spent in flight. In the same subjects, the muscle mass of the lower limbs, as assessed by NMR, decreased by 9-13%, irrespective of flight duration (J. Zange, K. Müller, M. Schuber, H. Wackerhage, U. Hoffmann, R. W. G unther, G. Adam, J. M. Neuerburg, V. E. Sinitsyn, A. O. Bacharev, and O. I. Belichenko. Int. J. Sports Med. 18, Suppl. 4: S308-S309, 1997). The larger fall in maximal power, compared with that in muscle mass, suggests that a fraction of the former (especially relevant for MEP) is due to the effects of weightlessness on the motor unit recruitment pattern.

Adult↗
PubMed1998

The current risk of retroviral infections transmitted by transfusion in patients who have undergone multiple transfusions. Cooleycare Cooperative Group.

BACKGROUND: To conduct a multicenter, prospective survey within the program of the Cooleycare Cooperative Group to evaluate the rate of transfusion-transmitted infections with human immunodeficiency virus (HIV) and human T-lymphotropic virus (HTLV) in a cohort of patients who were homozygous for beta thalassemia and underwent multiple transfusions during the 6-year follow-up. PATIENTS AND METHODS: One thousand three hundred eighty-four patients with beta thalassemia from 36 centers were enrolled from December 1989 to March 1990. Serum samples were tested at regular intervals during the period from December 1989 to March 1996 for anti-HIV and anti-HTLV antibodies in 1 laboratory. Samples from 1073 and 1001 of the 1384 patients were available for evaluation also during the periods from December 1992 to March 1993 and December 1995 to March 1996, respectively. The risk of acquiring infection was calculated by the ratio between the number of patients who experienced seroconversion and the number of red blood cell units administered to the patients during the study period. RESULTS: The prevalence of HIV infection found in the period from December 1989 to March 1990 was 2.9% (40 of 1384 patients). During follow-up, 1 of 1001 patients showed anti-HIV seroconversion. The incidence of HIV infection was 1.7 per 10,000 person-years (upper boundary of the 95% confidence interval, 5 per 10,000). The risk of HIV infection was 1 in 190,000 U (upper boundary of the 95% confidence interval, 1 in 67,000). At baseline, 4 patients were infected with HTLV (3 with HTLV-1 and 1 with HTLV-2). No seroconversions were observed during follow-up; the risk of HTLV infection was less than 1 in 190,000 U. CONCLUSION: The application of reliable screening procedures for donor selection reduced the transmission of transfusion-associated HIV infection in 1989-1995 to fewer than 2 cases in 10,000 person-years or 1 case per 190,000 units of red blood cells.

Adolescent↗
PubMed1998

The incidence and natural course of transfusion-associated GB virus C/hepatitis G virus infection in a cohort of thalassemic patients. The Cooleycare Cooperative Group.

To evaluate the risk of transmitting blood-borne GB virus C/hepatitis G virus (GBV-C/HGV) and to define the natural course of infection, we performed a prospective study in a cohort of multitransfused beta-thalassemics during a 6-year follow-up period. We analyzed serum samples of 150 patients collected at 3-year intervals from 1990 to 1996. GBV-C/HGV RNA was determined by reverse transcriptase-polymerase chain reaction and antibodies to E2-protein by an enzyme immunoassay. At baseline, 14.5% of patients had viremia and 18.5% anti-E2. None of the patients with anti-E2 in 1990 subsequently became viremic. Of the 100 GBV-C/HGV RNA-, anti-E2- patients, 10 acquired infection during follow-up, as indicated by positivity of GBV-C/HGV RNA (n = 2), anti-E2 (n = 7), or both markers (n = 1) in 1996. The incidence was 1.7 per 100 person-years (95% confidence interval [CI], 0.8 to 3). Since approximately 19,000 blood units were transfused to these patients during follow-up, the risk of infection was 5.3 in 10,000 units (95% CI, 2 to 8.5). Six of 22 viremic patients cleared the virus during follow-up; 4 of them became anti-E2+. Twelve of 28 patients lost anti-E2 reactivity during follow-up. In conclusion, more than 25% of infections resolve within 6 years; the presence of anti-E2 seems to be protective against infection. Anti-E2 reactivity may decrease with time.

Adolescent↗
PubMed1998

Energetics of swimming at maximal speeds in humans.

The energy cost per unit of distance (Cs, kilojoules per metre) of the front-crawl, back, breast and butterfly strokes was assessed in 20 elite swimmers. At sub-maximal speeds (v), Cs was measured dividing steady-state oxygen consumption (VO2) by the speed (v, metres per second). At supra-maximal v, Cs was calculated by dividing the total metabolic energy (E, kilojoules) spent in covering 45.7, 91.4 and 182.9 m by the distance. E was obtained as: E = Ean + alphaVO2maxtp - alphaVO2maxtau(1 - e(-(tp/tau))), where Ean was the amount of energy (kilojoules) derived from anaerobic sources, VO2max litres per second was the maximal oxygen uptake, alpha( = 20.9 kJ x 1 O2(-1)) was the energy equivalent of O2, tau (24 s) was the time constant assumed for the attainment of VO2max at muscle level at the onset of exercise, and tp (seconds) was the performance time. The lactic acid component was assumed to increase exponentially with tp to an asymptotic value of 0.418 kJ x kg(-1) of body mass for tp> or =120 s. The lactic acid component of Ean was obtained from the net increase of lactate concentration after exercise (delta[La]b) assuming that, when delta[La]b = 1 mmol x 1(-1) the net amount of metabolic energy released by lactate formation was 0.069 kJ x kg(-1). Over the entire range of v, front crawl was the least costly stroke. For example at 1 m x s(-1), Cs amounted, on average, to 0.70, 0.84, 0.82 and 0.124 kJ x m(-1) in front crawl, backstroke, butterfly and breaststroke, respectively; at 1.5 m x s(-1), Cs was 1.23, 1.47, 1.55 and 1.87 kJ x m(-1) in the four strokes, respectively. The Cs was a continuous function of the speed in all of the four strokes. It increased exponentially in crawl and backstroke, whereas in butterfly Cs attained a minimum at the two lowest v to increase exponentially at higher v. The Cs in breaststroke was a linear function of the v, probably because of the considerable amount of energy spent in this stroke for accelerating the body during the pushing phase so as to compensate for the loss of v occurring in the non-propulsive phase.

Adolescent↗
PubMed1998

Energetics of best performances in track cycling.

VO2max and best performance times (BPTs) obtained during maximal voluntary trials over 1, 2, 5, and 10 km from a stationary start were assessed in 10 elite cyclists. Steady-state VO2 and peak blood lactate concentration ([La]b) were also determined in the same subjects pedaling on a track at constant submaximal speeds. The energy cost of cycling (Cc, J.m-1) was calculated as the ratio of VO2, corrected for glycolytic energy production and expressed in W, to v (m.s-1). Individual relationships between Cc and v were described by: Cc = Ccrr + k1 v2 where Ccrr is the energy spent against friction and k1 v2 is that spent against drag. Overall energy cost of cycling (Cctot) was obtained, adding to Cc the energy spent to accelerate the total moving mass from a stationary start. Individual theoretical BPTs were then calculated and compared with the actual ones as follows. The maximal metabolic power sustained at a constant level by a given subject (Emax, W) is a known function of the exhaustion time (te). It depends on his VO2max and maximal anaerobic capacity; it was obtained from individual VO2max and [La]b values. The metabolic power (Ec, W) necessary to cover any given distance (d) is a known function of the performance time over d (td); it is given by Ec = Cctot v = Cctot d td. For all subjects and distances, the t values solving the equalities Emax F(te) = Ec F(td) were calculated and assumed to yield theoretical BPTs. Calculations showed a fairly good agreement between actual and calculated BPTs with an average ratio of 1.035 +/- 0.058.

Adolescent↗
PubMed1997

The incidence and risk factors of community-acquired hepatitis C in a cohort of Italian blood donors.

To assess the incidence and source of community-acquired hepatitis C virus (HCV) infection among subjects at low risk for blood-borne diseases, we prospectively studied a cohort of 16,515 repeat blood donors over a mean follow-up time of 36 months. Second- and third-generation methods were used for hepatitis C virus antibody (anti-HCV) testing. HCV RNA was determined in the serum of anti-HCV-positive donors by reverse-transcription polymerase chain reaction. Liver biopsy was performed in the viremic subjects. Risk factors for HCV infection were identified by a psychosocial questionnaire in the whole cohort. During follow-up, 5 donors became infected with HCV. The incidence was 1 per 10,000 person-years (95% confidence interval, 0.3-2.4 per 10,000). During the 6 months before seroconversion, four subjects (80%) underwent medical or surgical percutaneous procedures, compared with 26.5% in the entire donor cohort (difference between frequencies, 53.5%; CI: 18.9-89.1). One seroconverting donor had sexual intercourse with an infected subject. Only 1 infected donor developed clinically evident acute hepatitis. HCV RNA remained detectable in 4 of 5 subjects for 8 to 36 months after seroconversion, and liver biopsy showed chronic hepatitis in all cases. Thus, new cases of hepatitis C occur among individuals without a history of known risk factors, some of which may be caused by nosocomial exposure.

Adult↗
PubMed1997

Effects of elastic recoil on maximal explosive power of the lower limbs.

The maximal explosive power during a two legs jump was measured on four competitive athletes [mean age 24(SD 4.3) years; height 1.79 (SD 0.09) m; body mass 68.7 (SD 12.8) kg] at different starting knee angles (70, 90, 110, 130 and 150 degrees). The experiments were performed on a newly developed instrument with which both force and speed could be measured using a force platform and a wire tachometer, respectively, and on a conventional force platform. At the smallest knee angle (70 degrees) the mean power output (W in watts per kilogram) developed during the jump was found not to differ significantly between the two methods (P > 0.1). At the larger knee angles W was 18.4% (90 degrees), 34.5% (110 degrees), 47.4% (130 degrees) and 19.4% (150 degrees) higher using the conventional force platform (P < 0.05 throughout). The difference of W between the two methods was attributed to the recovery of elastic energy due to the counter movement which immediately preceded the jump on the conventional platform, but not on the newly developed instrument. Indeed because of a mechanical arrangement which prevented the subject from moving towards the platforms, eccentric work (W-) could not be performed on the newly developed instrument; whereas W- on the conventional force platform was almost negligible at 70 degrees knee angle [mean 1.7 (SD 2.3 J)] reached a maximum of 13.1 (SD 7.9) J at 130 degrees and decreased again to a mean 4.7 (SD 3.6) J for the largest angle (150 degrees). Furthermore, on the conventional force platform, the force at the onset of the positive speed phase (Fi) was an increasing function of W- (r2 = 0.519, P < 0.001); and the difference of W between the conventional and new instruments was larger the larger the difference of Fi (r2 = 0.391, P < 0.01).

Adult↗
PubMed1997

Sexual transmission of hepatitis C virus to a repeat blood donor.

BACKGROUND: Sexual transmission of hepatitis C virus (HCV) can occur, albeit inefficiently, and this represents a possible cause of community-acquired infections. This study describes a case of asymptomatic HCV infection acquired by a repeat blood donor from her sexual partner. CASE REPORT: A female repeat blood donor showed anti-HCV seroconversion and a slight elevation in alanine aminotransferase. She had a normal physical examination and no clinical symptoms. She admitted a sexual partnership with a man with chronic HCV infection. Genotyping showed subtype 3a infection in both. Nucleotide sequence analysis of the hypervariable region of the viral envelope was performed on five clones obtained from the donor and the partner. Five blood donors with subtype 3a infection were analyzed as controls. The mean homology among clones was 99.3 percent (95% CI, 98.9-99.7) in the donor and 96.8 percent (95% CI, 94.4-99.2) in the partner, which suggests a more recent infection in the woman. The mean homology between donor and partner was 93.4 percent (95% CI, 93.1-93.8), which is different from that between donor and controls (76.2%; 95% CI, 73.3-79.1; difference between means, 17.2%; 95% CI, 16.0-18.4). This suggests that the infection was transmitted to the donor from her sexual partner. Sexual intercourse is the most probable route of transmission, because parenteral risk factors were absent. CONCLUSION: Heterosexual transmission of HCV can occur in the absence of a long-lasting contact, and the infection can be asymptomatic. It remains to be determined whether the sexual partners of HCV-infected subjects should be deferred from blood donation.

Adult↗
PubMed1997

Quantitative evaluation of the Myotatic Reflex in Hemiplegic and Paraplegic patients.

The aim of this study was the quantitative evaluation of the myotatic reflex in a group of 11 subjects affected by spastic paresis of the lower limbs (8 hemiplegic and 3 paraplegic patients) and, for comparison, in a group of 7 healthy subjects. The parameters taken into account were the gain of the reflex and the time delay between the input and the mechanical output. The gain was calculated as the ratio between: i) the peak value of the input force (FPH) measured by means of an instrumented hammer with which the patellar tendon was hit; and ii) the peak value of the corresponding reflex force of the quadriceps femoris (FPQ) measured by means of a load cell connected to the subject's ankle. The gain of the reflex (FPQ/FPH) was found to be 1.9 to 2.4 times larger in patients as compared to control subjects and, among the patients to be twice at low, as compared to high, levels of stimulation. Among the hemiplegic patients, significant differences were found in the time delay of the response between the affected and unaffected limbs. Since both the intensity of the reflex and its gain were found to depend on the mechanical energy input, both parameters must be taken in to account if a diagnosis of spasticity has to be made.

Journal Article↗