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Biomedical subjects

S Jacob

Publications and source records attributed to S Jacob.

At least 55 records · Page 3Linked to original sources

Utilisation of intramyocellular lipids (IMCLs) during exercise as assessed by proton magnetic resonance spectroscopy (1H-MRS).

Recently, a 1H-MRS method became available to quantify intramyocellular lipids (IMCL) non-invasively. Currently, little is known about the regulation of this lipid pool. During prolonged exercise of moderate intensity, non-plasma-derived fatty acids play an important role as an energy source; lipids located within the skeletal muscle are considered to be a major source for these fatty acids. To see whether IMCL are reduced by exercise, 12 male runners were studied before and after exercising at different workloads and duration. Six subjects participated in a non-competitive run (NCR), three runners in a competitive half marathon (HM, 21 km) and another three in a competitive marathon (M, 42 km). Intra- and extramyocellular lipids were quantified by 1H-MR spectroscopy in the tibialis anterior (TA) and soleus (SOL) muscles prior to and after the exercise bout. Moderate intensity (MI; 60-70% VO2max in NCR) with a mean exercise time (MET) ranging between 105-110 min decreased IMCL by 10 - 36% in both muscles. Prolonged MI exercise (MET 210-240 min; 68-70% VO2max in M) reduced IMCL by 42-57% in TA and 27 - 56% in SOL. In contrast, high intensity exercise (HI; MET 80-120 min; 83-85% VO2max in HM) did not alter IMCL in either muscle. Extramyocellular lipids (EMCL) did not show any significant change in any group. The data show that one bout of moderate-intensity (60-70% VO2max) aerobic exercise markedly reduces the IMCL in TA and SOL muscles in a time-dependent fashion as assessed by 1H-MRS. However, exercise of similar duration but higher workload (> 80% VO2max) does not reduce IMCL. These data suggest that both exercise duration and workload are important factors in determining the reduction of IMCL.

Adult↗

Impaired non-esterified fatty acid suppression is associated with endothelial dysfunction in insulin resistant subjects.

In a recent study, we found a significant association between insulin resistance (IR) and disturbed flow-associated (endothelial-dependent) vasodilation in first-degree relatives of subjects with type 2 diabetes. However, the mechanisms linking insulin resistance and endothelial dysfunction (ED) have not been fully elucidated. Experimental data have pointed out that non-esterified fatty acids (NEFA) have a modulating effect on NO-synthase activity, and therefore on endothelial function. The aim of our study was to evaluate whether insulin resistance associated impaired NEFA suppression is present in subjects with ED. We examined 53 first-degree relatives (FDR) of patients with type 2 diabetes (32f, 21 m, mean age 35 years). Endothelial function was measured as flow-associated vasodilation (FAD%) of the brachial artery. Insulin sensitivity was evaluated with a standard hyperinsulinemic glucose clamp (insulin infusion rate of 1 mU/kg/min). While under fasting conditions, NEFA did not differ between groups with high or low FAD (0.415+/-0.033 vs. 0.394 +/- 0.040 mmol/l; p = n. s.), reduced FAD% was significantly associated with higher non-esterified fatty acids concentrations during steady state of the glucose clamp (0.072+/-0.022 vs. 0.039+/-0.016mmol/l; p=0.04). This association was independent of insulin levels under fasting conditions and during the glucose clamp. In conclusion, our results reveal a significant association between endothelial dysfunction and impaired non-esterified fatty acid suppression in insulin resistant subjects. As insulin resistance of lipolysis is a feature of the insulin resistance syndrome, these results suggest that elevated NEFA concentrations could play a role linking endothelial dysfunction and insulin resistance in vivo.

Adult↗

Selective angiotensin II receptor antagonism reduces insulin resistance in obese Zucker rats.

Effects of oral administration of the angiotensin II receptor antagonist (selective AT(1)-subtype) irbesartan on glucose tolerance and insulin action on skeletal-muscle glucose transport were assessed in the insulin-resistant obese Zucker rat. In the acute study, obese rats received either vehicle (water) or irbesartan 1 hour before the experiment. Although irbesartan had no effect on glucose transport (2-deoxyglucose uptake) in the epitrochlearis muscle, which consists mainly of type IIb fibers, acute angiotensin II receptor antagonism led to a dose-dependent increase in insulin action in the predominantly type I soleus muscle. Irbesartan at 25 and 50 mg/kg induced significant increases (41% and 50%, respectively; P<0.05) in insulin-mediated glucose transport. Moreover, these acute irbesartan-induced improvements in soleus-muscle glucose transport were associated with enhancements in whole-body insulin sensitivity (r=-0.732; P<0.05), as assessed during an oral glucose tolerance test. After chronic administration of irbesartan (21 days at 50 mg. kg(-1). d(-1)), glucose tolerance was enhanced further, and insulin-mediated glucose transport was significantly elevated in both epitrochlearis (32%) and soleus (73%) muscle. Chronic angiotensin II receptor antagonism was associated with significant increases in glucose transporter-4 (GLUT-4) protein expression in soleus (22%) and plantaris (20%) muscle and myocardium (15%). Chronic irbesartan-induced increases in whole-body insulin sensitivity were associated with increased insulin-mediated glucose transport in both epitrochlearis (r=-0.677; P<0.05) and soleus (r=-0.892; P<0.05) muscle. In summary, angiotensin II receptor (AT(1)-subtype) antagonism, either acutely or chronically, improves glucose tolerance, at least in part because of an enhancement in skeletal-muscle glucose transport, and the effect of chronic angiotensin II receptor antagonism on type I skeletal-muscle glucose uptake is associated with an increase in GLUT-4 protein expression.

Angiotensin Receptor Antagonists↗

Effects of intravenous and dietary lipid challenge on intramyocellular lipid content and the relation with insulin sensitivity in humans.

An increased intramyocellular lipid (IMCL) content, as quantified by (1)H-magnetic resonance spectroscopy ((1)H-MRS), is associated with reduced insulin sensitivity. At present, it is unclear which factors determine IMCL formation and how rapidly IMCL accumulation can be induced. We therefore studied the impact of hyperinsulinemia and elevated circulating nonesterified fatty acid (NEFA) levels on IMCL formation and insulin sensitivity. We further evaluated the influence of a high-fat diet on IMCL storage. In the infusion protocol, 12 healthy male subjects underwent a 6-h hyperinsulinemic-euglycemic glucose clamp with concomitant infusion of Intralipid plus heparin. IMCL was quantified by (1)H-MRS in soleus (SOL) and tibialis anterior (TA) muscle at baseline and then every hour. IMCL levels started to increase significantly after 2 h, reaching a maximum of 120.8 +/- 3.4% (SOL) and 164.2 +/- 13.8% (TA) of baseline after 6 h (both P < 0.05). In parallel, the glucose infusion rate (GIR) decreased progressively, reaching a minimum of 60.4 +/- 5.4% of baseline after 6 h. Over time, the GIR was strongly correlated with IMCL in TA (r = -0.98, P < or = 0.003) and SOL muscle (r = -0.97, P < or = 0.005). In the diet protocol, 12 male subjects ingested both a high-fat and low-fat diet for 3 days each. Before and after completion of each diet, IMCL levels and insulin sensitivity were assessed. After the high-fat diet, IMCL levels increased significantly in TA muscle (to 148.0 +/- 16.9% of baseline; P = 0.005), but not in SOL muscle (to 114.4 +/- 8.2% of baseline; NS). Insulin sensitivity decreased to 83.3 +/- 5.6% of baseline (P = 0.033). There were no significant changes in insulin sensitivity or IMCL levels after the low-fat diet. The effects of the high-fat diet showed greater interindividual variation than those of the infusion protocol. The data from the lipid infusion protocol suggest a functional relationship between IMCL levels and insulin sensitivity. Similar effects could be induced by a high-fat diet, thereby underlining the physiological relevance of these observations.

Adult↗

Pro12Ala polymorphism in the peroxisome proliferator-activated receptor-gamma2 gene is associated with increased antilipolytic insulin sensitivity.

The Pro12Ala polymorphism of the peroxisome proliferator-activated receptor (PPAR)-gamma2 is associated with reduced transcriptional activity in vitro and increased insulin sensitivity in humans in vivo. The mechanism by which this polymorphism influences insulin sensitivity in humans is unclear. PPAR-gamma2 is mainly expressed in adipocytes, and free fatty acids released from adipose tissue are key mediators of peripheral insulin resistance. Therefore, we examined insulin suppression of lipolysis in 51 subjects without (Pro/Pro) and 17 subjects with the polymorphism (X/Ala). Both groups were lean (BMI <27.0 kg/m2) and matched for age, BMI, waist-to-hip ratio, and sex. The isotopically (infusion of d5 glycerol) determined glycerol rate of appearance was used as an index of lipolysis. Insulin sensitivity of lipolysis was expressed as the insulin concentration resulting in half-maximal suppression (EC50). This was directly determined during a three-step hyperinsulinemic-euglycemic clamp (n = 21) or estimated indirectly during a standard hyperinsulinemic-euglycemic clamp (n = 47). The insulin sensitivity index (ISI) of glucose disposal was 0.095+/-0.006 micromol x kg(-1) x min(-1) x pmol(-1) x l(-1) in the control group and 0.129+/-0.008 micromol x kg(-1) x min(-1) x pmol(-1) x l(-1) in the X/Ala group (P = 0.003). The EC50 was 56+/-2 pmol/l in the control group and 44+/-3 pmol/l in the X/Ala group (P = 0.001). The EC50 of lipolysis and ISI was significantly correlated (r = 0.42, P = 0.002). In conclusion, in lean subjects, the Pro12Ala polymorphism is associated with increased insulin sensitivity of glucose disposal and suppression of lipolysis. This result suggests that an altered transcriptional activity of PPAR-gamma2 in X/Ala subjects either causes a more efficient suppression of lipolysis in adipose tissue, which in turn results in improved insulin-stimulated glucose disposal in muscle, or, alternatively, beneficially affects insulin signaling in both tissues independently of one another.

Adult↗

Laparoscopically assisted vaginal management of deep endometriosis infiltrating the rectovaginal septum.

BACKGROUND: Two aims: 1) To assess the results of laparoscopically assisted vaginal management of deep endometriosis infiltrating the rectovaginal septum (RVS); 2) to pinpoint the differences between this procedure and that used for deep endometriotic lesions located on the uterosacral ligaments (USL). METHODS: Descriptive retrospective study. Twenty-nine consecutive patients operated for deep endometriosis infiltrating the RVS were included in this series. RESULTS: One patient only (3.5%) presented a major complication of the recto-vaginal fistula type. After a one step reoperation under anesthesia, the post operative history was uncomplicated and no sequelae are to be deplored. With respect to dysmenorrhea (DM), deep dyspareunia (DP) and chronic pelvic pain (CPP), there was an improvement in respectively 91.7% (22 patients), 100% (24 patients) and 92.9% (13 patients) of cases. For each of these 3 symptoms the median score according to the visual analog scale was significantly lower after the operation (for DM: 7.6+/-2.0 versus 1.7+/-2.6; for DP 7.5+/-1.9 versus 0.5+/-1.1; for CPP 5.9+/-2.8 versus 1.4+/-3.2) (p<0.0001). CONCLUSIONS: These results demonstrate that provided the surgeon is highly skilled in laparoscopy, operative laparoscopy is efficient for the treatment of patients presenting painful symptoms related to deep endometriotic infiltrating the RVS. From the technical point of view the rectum must be freed, leaving the deep endometriotic nodule attached to the posterior wall of the vagina. Resection of the whole lesion requires the posterior wall of the vagina to be resected, whereas ureterolysis is often unnecessary. So for lesions located on the RVS the vagina is opened systematically, unlike the situation when resecting deep endometriotic lesions infiltrating the USL. Deep pelvic endometriosis is not synonymous with endometriosis of the RVS. Lesions truly infiltrating the RVS represent only a small proportion of all deep endometriosis lesions.

Adult↗

Pregnancy in women with epilepsy : preliminary results of Kerala registry of epilepsy and pregnancy.

Eighty-five women with epilepsy were followed up for reproductive functions under the registry of epilepsy and pregnancy. 32 of them had completed the pregnancy. Their mean age was 26 years and mean seizure frequency was 0.7 during current pregnancy. Nineteen of them (59.4%) had generalized epilepsy. Nine of them were not on any anti epileptic drugs (AED), 23 women were on various AEDs, 19 being on monotherapy. Only 40% of the women were taking folic acid during pregnancy. Pregnancy ended as spontaneous abortion in one patient. Nearly one third required cesarean section. Majority (87.5%) had term babies. Three (10.7%) babies had birth asphyxia. Six babies (21.4%) had low birth weight. Congenital malformations were detected in four cases (12.5%). Malformations included neural tube defects, talipes equinovarus and other minor anomalies. These babies were exposed to sodium valproate, carbamazepine or phenobarbitone. The risk of malformation was significantly greater (p<0.05) when the mother had generalized epilepsy. The odds ratio for risk of malformation was much higher with sodium valproate (6) than that with carbamazepine (1.2) or phenobarbitone (0.8). Majority of women with epilepsy had safe pregnancy and childbirth without any aggravation of epilepsy.

Adult↗

Management of symptomatic ureteric stumps laparoscopically.

AIM: To study the advantage of excision of the distal symptomatic ureteric stumps with the retroperitoneal laparoscopic approach. METHODS: Four patients who had failed to settle their symptoms with the initial conservative management were included in the study. All underwent excision of the distal symptomatic ureteric stumps with the retroperitoneal laparoscopic approach and then received prophylactic antibiotics. RESULTS: We have achieved better results than those reported in the literature in terms of operating time (mean 1 h 45 min), blood loss (< 10 mL), postoperative recovery (within 12 h) and hospital stay (< 48 h). CONCLUSION: Retroperitoneal laparoscopic excision is a safe, simple and effective method in the management of symptomatic ureteric stumps.

Adult↗

Two novel prevalent polymorphisms in the hormone-sensitive lipase gene have no effect on insulin sensitivity of lipolysis and glucose disposal.

Free fatty acids released during triglyceride lipolysis play an important role in obesity-associated insulin resistance of glucose disposal. Individual sensitivity of lipolysis to the suppressive effect of insulin varies greatly among healthy subjects. It is possible that genetic factors contribute to this variation. Among the many proteins involved in the regulation of lipolysis, hormone-sensitive lipase (HSL) represents a prime candidate for genetic variants contributing to the biological variation of insulin sensitivity of lipolysis. We determined the insulin sensitivity of lipolysis (suppression of isotopically [primed-continuous infusion of d5 glycerol] measured glycerol rate of appearance) and of glucose disposal, using a three-step (n = 20) or standard (n = 53) hyperinsulinemic euglycemic clamp in 73 healthy, unrelated subjects. To assess the possible role of genetic polymorphisms, we directly sequenced the coding region of the HSL gene and the noncoding exon B from these subjects. We identified two silent mutations and three amino acid polymorphisms: Arg262Met (prevalence, 5%), Glu620Asp (prevalence, 31%) and Ser681Ile (prevalence, 22%). The latter two are located in the regulatory domain of HSL but neither had a significant impact on insulin sensitivity of lipolysis or glucose disposal (with and without adjustment for obesity and age as covariates; all P values > 0.20). We conclude that a number of genetic polymorphisms in HSL exist, some of which are highly prevalent. Neither of the polymorphisms we identified in the coding region, however, contributed measurably to the biological variation of insulin sensitivity in our lean, healthy population.

Adult↗

Endothelial dysfunction is detectable in young normotensive first-degree relatives of subjects with type 2 diabetes in association with insulin resistance.

BACKGROUND: Endothelial dysfunction (ED) is regarded as an early step in the development of atherosclerosis. Among the pathogenetic factors leading to atherosclerosis, the role of insulin resistance and hyperinsulinemia as independent risk factors is still under debate. In this study, we examined the association between ED and insulin resistance in normotensive and normoglycemic first-degree relatives (FDRs) of patients with type 2 diabetes mellitus (DM). METHODS AND RESULTS: Endothelium-dependent and -independent vasodilation of the brachial artery was measured with high-resolution ultrasound (13 MHz) in 53 normotensive FDRs (21 men, 32 women; mean age, 35 years) with normal oral glucose tolerance, 10 age- and sex-matched normal control subjects, and 25 DM patients (mean age, 57 years). According to the tertiles of the clamp-derived glucose metabolic clearance rate (MCR), the FDRs were further classified as insulin resistant with an MCR or =7.8 mL. kg(-1). min(-1), and borderline with an MCR of 5.9 to 7.7 mL. kg(-1). min(-1). Flow-associated dilation was 4.1+/-0.9% in insulin-resistant FDRs, 6.7+/-1.1% in borderline FDRs, 9.0+/-1.2% in insulin-sensitive FDRs (P=0.002), 7.7+/-2.9% in control subjects (P=NS versus FDRs), and 3.8+/-1.0% in DM patients (P=0.03). In multiple regression analysis, low MCR was significantly correlated with ED independent of age, sex, smoking, body mass index, percent body fat, serum insulin, and lipids. CONCLUSIONS: There is a significant association between ED and insulin resistance in young FDRs of DM subjects independent of the classic cardiovascular risk factors.

Adolescent↗

Location and gross morphology of the nasopalatine duct in human adults.

OBJECTIVE: To characterize the nasal opening of the human nasopalatine duct (NPD; a major duct of the vomeronasal system used in animals for chemical communication) by identifying its location, categorizing variations in physical characteristics, and assessing frequency of detection. DESIGN: Two studies: (1) general study incorporating endoscopic examinations documented by videotapes and photographs, and an investigation of detection bias in terms of method of visualization and defining criteria for NPD identification; and (2) cadaver dissections examining NPD gross anatomy and proximity to the putative vomeronasal organ (VNO), the second major duct of the vomeronasal system. SETTING: Department of Otolaryngology, University of Chicago Hospitals, Chicago, Ill. SUBJECTS: A total of 125 university community volunteers, with a mean age of 23 years. RESULTS: (1) General study: NPD was located 1.9+/-0.02 cm (mean+/-SEM) dorsal to the columella nasi, and 0.2+/-0.01 cm above the nasal floor/septum junction, in both nostrils (90% bilateral), and was symmetrical in shape. An NPD was detected in 94% of 221 nostrils unobstructed in the region of interest. Fossa shapes were oval (57%), round (18%), spindle-shaped (18%), and tubular (7%). A small, round aperture was visualized in 30% of fossae. Among 3 observers, NPD detection frequency ranged from 94% to 40%, with the disparity due to inclusion of different defining characteristics. (2) Cadaver dissection study: bilateral nasal NPD fossae were found in every specimen probed to maximum approximate depth of 8 mm. No buccal pits associated with patent NPD were detected. Putative VNOs superior and just anterior to NPD fossae were detected in fewer than half the specimens. CONCLUSIONS: The nasal opening of the NPD is bilateral and symmetrical, located at the base of the nasal septum. Unusually contradictory anatomical descriptions in the human putative VNO literature may be attributable to inexact descriptions or misidentification of structures. The function of NPD remains controversial.

Adolescent↗

Acquired generalized lipoatrophy (AGL): highly selective MR lipid imaging and localized (1)H-MRS.

Frequency-selective chemical shift magnetic resonance (MR) imaging was applied on the calf musculature and the abdomen of a patient with acquired generalized lipoatrophy (AGL; Lawrence syndrome), a very rare syndrome affecting selectively several types of adipose tissue accompanied by alterations in glucose and energy metabolism. In addition, (1)H-MRS was used for assessment of intra- (IMCL) and extramyocellular lipid stores (EMCL) in the skeletal musculature of the calf. Results from the AGL patient were compared with an age-matched group of five healthy volunteers. Fat-selective imaging of the calf revealed a total lack of subcutaneous adipose tissue. No EMCL signal was found in the spectra from the soleus muscle of the AGL patient. IMCL signals were present in the spectra but were clearly lower than in the controls (14% of normal value in the soleus muscle). In abdominal images, subcutaneous fat signal was not detectable, as in the calf, but nearly normal conditions were shown for visceral adipose tissue between abdominal organs. Fat-selective images showed the liver with high signal intensity, indicating hepatic steatosis combined with hepatosplenomegaly. Modern chemical shift-selective MR imaging and localized spectroscopy allow a noninvasive and quantitative assessment of tissue composition in patients with disorders of carbohydrate and lipid metabolism.

Adipose Tissue↗

Psychological state and mood effects of steroidal chemosignals in women and men.

We tested the hypothesis that isolated steroids, claimed to act like pheromones, affect human psychological state or mood. In the first experiment, we established that two steroids, Delta4, 16-androstadien-3-one and 1,3,5(10)16-estratetraen-3-ol, modulated emotional states within 6 min of exposure. In men and women, neither steroid had specific effects on states of alertness or negative-confused mood. However, both steroids increased positive stimulated mood state in women but decreased it in men. These psychological findings do not parallel the reported sexually specific effects of these two steroids on the surface potential activity of putative vomeronasal epithelium. In a second experiment on women, we replicated that Delta4,16-androstadien-3-one modulated their general mood state, even when women were not aware of its odor and gave identical olfactory descriptions for the steroid and the control carrier solutions. In this within-subjects, repeated-measures experiment, androstadienone prevented the deterioration in general mood which occurred during exposure to the clove oil carrier solution in the laboratory environment. Thus, androstadienone appears to modulate affect, rather than releasing stereotyped behaviors or emotions. It is premature to call these steroids human pheromones. They are nonetheless psychologically potent, mandating future work delineating their function-i.e., whether these steroids are communicative chemosignals, context specific, or related to unconscious associations. In light of these modulatory effects and the complexity of human behavior, the function of chemosignals and pheromonal systems in a variety of species may need to be expanded to include the concept of modulators, as well as the traditional releasers, primers, and signaling compounds.

Adult↗

Spontaneous conception after a successful attempt at in vitro fertilization/intracytoplasmic sperm injection.

OBJECTIVE: To determine the incidence of spontaneous pregnancy in women who were not actively undergoing therapy after a successful attempt at IVF/intracytoplasmic sperm injection and to characterize its pattern of occurrence. DESIGN: Retrospective postal questionnaire. SETTING: An assisted reproduction unit at a university-based teaching hospital. PATIENT(S): Five hundred thirteen replies were received from 530 questionnaires mailed. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Spontaneous pregnancy. Women who did and did not conceive spontaneously after successful IVF treatment were compared in terms of their age, duration of infertility, previous reproductive history, and indication for treatment at the time of assisted reproduction. RESULT(S): The rate of spontaneous conception among the survey respondents was 20.7%. Younger women (</=34 years of age) had a higher rate of spontaneous conception, as did those with a shorter duration of infertility. Women with unexplained infertility and endometriosis also were more likely to conceive. Few of those who had undergone intracytoplasmic sperm injection conceived, whereas 21.6% of those whose partners had had sperm quality sufficient for IVF later conceived spontaneously. CONCLUSION(S): The chances of spontaneous conception after successful ART therapy are significant in some groups of patients. This has implications for the practice of assisted reproduction and the obstetric care of patients who conceive with treatment. Contraceptive advice may need to be provided to couples who undergo IVF/intracytoplasmic sperm injection.

Adult↗

An interleaved sampling strategy for MR spectroscopy in vivo: applications on human calf musculature.

Assessment of relaxation times, magnetization transfer rates, or apparent diffusion coefficients by volume selective (1)H MR spectroscopy requires data from several single spectra with variable sequence parameters. Unintentional movements during the examination lead to inaccuracies, especially if the spatial distribution of concentrations is inhomogeneous. Improved comparability of the single spectra in a series recorded in vivo were obtained using a modified spectroscopic technique with INTerleaved ACquisiTion of multiple SPECtra (INTACTSPEC). INTACTSPEC series of spectra from the tibialis anterior muscle (m. tib. ant.), soleus muscle (m. soleus), and tibial bone marrow of 20 healthy volunteers were analyzed. Transverse relaxation times T(2) of methylene signals in muscular lipid stores ranged from 77 ms (intramyocellular methylene component in m. tib. ant.) to 88 ms (intramyocellular methylene component in m. soleus) and were similar to those from yellow tibial bone marrow (T(2) = 84 ms). Echo time-dependent signal intensities of choline and creatine deviated markedly from a monoexponential behavior in m. tib. ant., but were nearly exponential in m. soleus. Results from water diffusion measurements parallel and perpendicular to the axis of the lower leg showed significant differences between m. tib. ant. and m. soleus, probably due to the spatial orientation of the muscle fibers. Apparent diffusion coefficients along the leg axis were found to be higher in m. tib. ant. (2.10 +/- 0.08 x 10(-3) mm(2)/s) compared to m. soleus (1.78 +/- 0.11 x 10(-3) mm(2)/s), but m. soleus showed less restricted diffusion in perpendicular orientation (1.59 +/- 0.19 x 10(-3) mm(2)/s versus 1.20 +/- 0.08 x 10(-3) mm(2)/s in m. tib. ant.). Magnetization transfer experiments with various RF preparation pulse amplitudes led to very similar results for m. tib. ant. and m. soleus.

Adult↗