Spin-lattice relaxation time in water/graphene-oxide dispersion.

We present the results of the calculations of the spin-lattice relaxation time of water in contact with graphene oxide by means of all-atom molecular dynamics simulations. We fully characterized the water-graphene oxide interaction through the calculation of the relaxation properties of bulk water and of the contact angle as a function of graphene oxide oxidation state and comparing them with the available experimental data. We then extended the calculation to investigate how graphene oxide alters the dynamical and relaxation properties of water in different conditions and concentrations. We show that, despite the diamagnetic nature of the graphene oxide, the confining effects of the bilayers strongly affect the longitudinal relaxation properties of interfacial water, which presents a reduced dynamics due to hydrogen bonds with oxygen groups on graphene oxide. This property makes graphene oxide an interesting platform to investigate water dynamics in confined geometries and an alternative contrast-agent for magnetic resonance imaging applications, especially in view of the possibility to functionalize graphene oxide from theranostic perspectives.

Relevance of chronic hepatitis E in liver transplant recipients: a real-life setting.

The chronic course of hepatitis E virus (HEV) infections in orthotopic liver transplant (OLT) recipients has been described previously, but prospectively collected data are rare. We aimed to study the role of chronic hepatitis E in OLT in a real-life setting. Therefore, 287 adult OLT recipients (169 male [59%], median age 56 years) were prospectively tested by HEV polymerase chain reaction assay (lower level of detection = 10 IU/mL), irrespective of their level of liver enzymes. In 4 patients (1.4%), chronic HEV infection was diagnosed. All 4 patients were male, and their age (median 48.5 years), the time since transplantation (median 45.5 months), and bilirubin level (median 0.6 mg/dL) did not differ significantly from the total cohort. However, alanine transaminase and aspartame transaminase levels were significantly higher in HEV-infected patients (75-646 U/L, median 216 U/L and 68-317 U/L, median 108 U/L) than in non-infected patients (6-617 U/L, median 41 and 6-355 U/L, median 36; P = 0.004 and 0.040, Mann-Whitney test). In 3 patients, liver biopsy was performed and revealed signs of inflammation and chronic liver disease, as enlarged densely infiltrated portal tracts with mild-to-moderate interface hepatitis. All infected patients were treated with ribavirin with the starting dose adjusted to renal function (400-800 mg/day). In 2 patients, dose reduction was necessary. Transaminases normalized in all 4 patients, and all patients cleared their infection within 3 months of ribavirin treatment. However, 1 patient experienced viral relapse 12 weeks after discontinuation. Ribavirin medication was re-started and viral clearance occurred within 8 weeks and persisted. Sequence analysis of the HEV genome of this patient revealed that he was infected with an HEV variant, which recently has been shown to have a reduced response to ribavirin in cell culture. The risk of chronic HEV infections in OLT recipients in low-endemic countries should not be overestimated. No case of chronic hepatitis E was observed in patients with normal liver enzymes, indicating that general screening of all OLT recipients is not necessary. However, if chronic hepatitis E develops, it can be treated efficiently with ribavirin.

Assessment of baseline characteristics and risk factors among Emergency Department patients presenting with recent onset atrial fibrillation: a retrospective cohort study.

BACKGROUND: The Cardioversion of Atrial Fibrillation in Emergency (CAFE) study was an observational, retrospective, multicenter study focusing on patients with recent onset atrial fibrillation (AF) seen in six different Emergency Departments (ED) of Rome, Italy. AIM: The aim of this study was to present the baseline characteristics and risk factors of the patients enrolled to the CAFE study. MATERIALS AND METHODS: We retrospectively reviewed 3085 eligible patients diagnosed with recent onset AF in any of the EDs between January 2008 and December 2009. Inclusion criteria required documented ICD-9 primary discharge/admission diagnosis of AF in the ED and stable hemodynamic conditions at presentation (systolic blood pressure > 90 mmHg). Exclusion criteria were permanent AF or an ongoing acute coronary syndrome. RESULTS: Median age was 71 years (interquartile ranges, 62-78 years) and 50.8% were men. Palpitations was the most common symptom at ED presentation and was present in 73.5% of the study subjects. Hypertension was the most prevalent comorbidity, affecting 59.3% of the patients evaluated, and the presence of previous episode(s) of AF was also common (52.3%). Regarding home treatment, the drugs most prescribed were antiplatelets (31.2%) and diuretics (25.2%). A CHADS2 score of 0 was found in 814 patients (26.4%), while a CHADS2 score of 1 was reported in 1114 patients (36.1%). Finally, a CHADS2 score ≥ 2 was reported in 1157 patients (37.5%). CONCLUSIONS: The present study represents an important snapshot of demographics, comorbidities, risk factors and anticoagulation management about patients with recent onset AF. Disparities were noted in anticoagulation management, suggesting that this is still a main problem among patients with AF.

Hepatocellular liver injury in hospitalized patients affected by COVID-19: Presence of different risk factors at different time points.

BACKGROUND: Prevalence and clinical impact of increased liver function tests in patients affected by Coronavirus disease 2019 (COVID-19) is controversial. AIMS: This observational study evaluates the prevalence of transaminases elevation in hospitalized patients affected by COVID-19 and investigates the presence of factors associated with hepatocellular injury and with mortality. METHODS: Data of 292 adult patients with confirmed COVID-19 admitted to the Ente Ospedaliero Cantonale (Switzerland) were retrospectively analyzed. RESULTS: Transaminases were increased in about one-third of patients on hospital admission and two-thirds of patients during the hospital stay. On hospital admission, transaminases were more commonly elevated in younger patients, who also reported elevated C reactive protein and a higher degree of respiratory failure. Independent factors associated with abnormal transaminases during hospitalization were drugs, in particular paracetamol (OR=2.67; 95% CI=1.38-5.18; p = 0.004) and remdesivir (OR=5.16; 95% CI=1.10-24.26; p = 0.04). Mortality was independently associated to age (OR = 1.09; 95% CI=1.05-1.13; p<0.001), admission to intensive care unit (OR=5.22; 95% CI=2.28-11.90; p<0.001) and alkaline phosphatase peak (OR=1.01; 95% CI=1.00- 1.01; p = 0.01). CONCLUSIONS: On hospital admission, factors associated with liver damage were linked to demographic and clinical characteristics (age, inflammation and hypoxia) while, during hospitalization, drug treatment was related to development and progression of hepatocellular damage. Mortality was associated with alkaline phosphate peak value.

Portal vein thrombosis: an overview of current treatment options.

Portal vein thrombosis (PVT) is a splanchnic vascular disorder characterised by a recent or chronic thrombotic occlusion of the portal venous system. Its aetiology is miscellaneous, and its management is demanding since PVT can play a critical role as far as morbidity and mortality are concerned. Indeed, PVT can develop as a complication of portal hypertension (PH), in association or not with advanced chronic liver disease, and aggravate its clinical consequences such as variceal bleeding and ascites. Furthermore, a diagnosis of PVT in a non-cirrhotic context can potentially reveal a previously unknown hypercoagulable condition, requiring further diagnostic steps and specific treatment in addition to anticoagulation. In addition to established therapeutic approaches, new strategies, including newer pharmacological treatments and interdisciplinary invasive procedures, gain more attention and have been increasingly introduced into clinical practice. This review aims at discussing the current knowledge in terms of treatment options for PVT.

Variation in collagenase Clostridium histolyticum practice patterns: a Survey of ISSM Members.

Collagenase clostridium histolyticum (CCH, Xiaflex, Xiapex) is the only FDA-approved medication for treatment of Peyronie's disease. It is unclear how practitioners actually use CCH in their own practices. The objectives of the study were: (1) to identify variability in practice patterns for CCH among practitioners, (2) to assess adherence to the package insert instructions, and (3) to evaluate whether provider satisfaction was associated with adherence to instructions. A 30-question online survey was distributed to 1270 members of the International Society for Sexual Medicine (ISSM) from the EU, USA, Canada and Australia. Of the 30 questions, 10 survey questions had only one response consistent with the CCH package insert recommendations. An "adherence" score was calculated for each survey participant depending on how many of these questions were answered correctly. The average adherence scores of various groups were compared using a student's t-test. A chi-squared test was used to determine association between categorical variables. Of 202 total responses, 132 practitioners reported using CCH out of 1270 ISSM members from countries where CCH is available (10.4% response rate). Practitioners from outside the USA were more likely to be satisfied with CCH (p = 0.006), and more experienced users (>20 uses) were more likely to be satisfied than less experienced users (<10 uses) (p = 0.046). Satisfied users of CCH did not have significantly different adherence scores than non-satisfied users. Even though 67% of practitioners believed they followed the package insert guidelines, only 11% adhered to all the recommendations evaluated by the survey. Treatment adherence to package insert guidelines does not appear to be associated with provider satisfaction. We believe there is utility in seeing a snapshot of these practice patterns so practitioners may feel more comfortable adapting their own practice in light of newer data supporting alternative administration methods.

Helicobacter pylori interference with micronutrients and orally administered drugs: a new mechanism explaining its role in extragastric disorders.

There is an increasing evidence that Helicobacter pylori may interfere with gastrointestinal metabolism of micronutrients and drugs such as iron, cobalamin, thyroxine and levodopa, with relevant clinical effects. In this review we examine the strength of the causal association and the plausible pathophysiologic mechanisms underlying these adverse effects.

[Guidelines for the treatment of child spasticity using botulinum toxin]. / Guía terapéutica de la espasticidad infantil con toxina botulínica.

AIMS: The introduction of botulinum toxin has been a significant step forward in the treatment of spasticity in children and is now considered to be the preferred treatment in focal spasticity. With the aim of optimising this therapeutic resource, a group of Spanish neurologists and specialists in rehabilitation have drawn up these therapeutic guidelines based on the currently available evidence on its use and indications, and on their own experience. DEVELOPMENT: Spasticity in childhood is mainly caused by infantile cerebral palsy. Its natural history is not favourable due to the negative effect of growth and it should be treated before permanent deformities in bones and joints appear. Treatment with botulinum toxin diminishes hyperactivity and muscle tone, and allows the muscle to grow longitudinally, which prevents permanent contractions. The advantages of botulinum toxin are obvious (ease of use and dosing, long-lasting effects, reversibility in case of adverse responses, and so forth) and outnumber by far the few drawbacks it offers. Before it can be used patients, treatment goals and the muscle areas to be treated must all be selected correctly and, at the same time, a tailored rehabilitation scheme must also be developed. The growing body of experience suggests that its early administration is effective in preventing or reducing the severe complications of spasticity. CONCLUSIONS: Botulinum toxin type A is very effective in the treatment of spasticity. These guidelines offer the well-documented experience gained from its use and our knowledge about its indications, effects and safety in clinical practice.

[Interaction between carbon nanotubes and cardiovascular autonomic nervous system regulation: proposal of an animal model and preliminary findings]. / Interazione tra nanotubi di carbonio e controllo cardiovascolare del sistema nervoso autonomo: presentazione di un modello sperimentale animale e risultati preliminari.

BACKGROUND: Altered autonomic cardiovascular regulation (ACR) may mediate the association between single-wall carbon nanotubes (SWCNT) exposure and adverse cardiovascular events. MATERIAL AND METHODS: 400 mg of SWCNT in 400 ml of phosphate buffer saline (PBS) or 400 ml of PBS were randomly given to 7 Wystar-Kyoto rats (400 g body wt) previously implanted in abdominal aorta with a telemetry transmitter for recordings of arterial pressure signals. Recordings were performed at baseline, 24 hours and two weeks after intratracheal instillation. The beat-by-beat time series of systolic arterial pressure (SAP) and PR interval were analyzed to identify sequences of three or more consecutive beats in which SAP and PR changed in the same (baroreflex sequences) or in the opposite direction (nonbaroreflex sequences). The mean individual slope of the sequences was calculated and taken as a measure of the baroreflex (BRS) and nonbaroreflex sensitivity for that period. RESULTS: The 24 hour BRS response showed a 100% increase (from 4.6 to 9.2 msec/mmHg) in controls, whereas it was blunted in cases (from 5.1 to 6.1 msec/mmHg) (p < 0.05). CONCLUSIONS: Our study demonstrates that this rat model is suitable to study the ACR during exposure to SWCNT and suggests a blunted BRS response after SWCNT instillation.

Shift work increases the frequency of duodenal ulcer in H pylori infected workers.

AIM: To evaluate whether shift work is associated with an increased rate of peptic ulcer in H pylori infected workers. METHODS: During a two year period, consecutive dyspeptic workers underwent non-invasive evaluation of H pylori status by means of urea 13C breath test or stool testing. Those testing positive were included in the study and divided into two main categories: day-time workers and shift workers. An upper gastrointestinal endoscopy was performed in all workers, and biopsy specimens were taken from the stomach to confirm the presence of H pylori infection (culture and histology). RESULTS: A total of 247 day-time workers and 101 shift workers were included. The prevalence of duodenal ulcer was significantly higher in shift workers than in day-time workers (29 of 101 v 23 of 247; OR = 3.92, 95% CI 2.13 to 7.21), and persisted after multivariate analysis, taking into account possible confounding factors (OR = 3.96, 95% CI 2.10 to 7.47). CONCLUSION: Shift work increases the ulcerogenic potential of H pylori infection and should be considered a risk factor for duodenal ulcer in infected shift workers. Treatment of infection in this high risk group may improve the health of workers and may reduce the economic impact of peptic ulcer.

Electron dose radiation response of dyed PMMA detectors developed at IPEN.

Dyed polymethylmethacrylate (PMMA) detectors using yellow, red, blue and green colouring compounds, commercially available in Brazil, were originally developed and characterised using the optical absorption (OA) technique for gamma radiation, with the aim of obtaining a sensitive, useful, practical and cheap dosemeter for use in the quality control of industrial gamma radiation processing. In this work these detectors were evaluated for electron OA response, for use in the quality control of electron accelerator radiation processing. The studied parameters were the absorption spectra, dose-rate dependence between 2.66 and 45.22 kGy s(-1); dose response between 1.2 and 110 kGy; and energy dependence of response between 0.8 and 1.5 MeV electron energy.

Effects of a residential exercise training on baroreflex sensitivity and heart rate variability in patients with coronary artery disease: A randomized, controlled study.

BACKGROUND: Myocardial ischemia and infarction impair baroreflex sensitivity (BRS), which when depressed is predictive of future cardiac events after myocardial infarction (MI). The main objective of this study was to determine whether exercise training improves BRS in patients with coronary artery disease. METHODS AND RESULTS: Ninety-seven male patients with and without a previous MI were recruited after myocardial revascularization surgery and randomized into trained (TR) or untrained (UTR) groups. TR patients underwent a residential exercise program at 85% of maximum heart rate (HRmax) consisting of 2 daily sessions 6 times a week for 2 weeks. Eighty-six patients (45 TR and 41 UTR) completed the study. BRS was assessed at baseline and at the end of the protocol by the spontaneous baroreflex method. The standard deviation of mean R-R interval (RRSD) was also assessed as a measure of heart rate variability. At baseline, there were no significant differences between TR and UTR patients in any variable. In TR patients, BRS increased from 3.0+/-0.3 to 5.3+/-0.7 ms/mm Hg (P:<0.001), RRSD from 18.7+/-1.4 to 23.6+/-1.6 ms (P:<0.01), and R-R interval from 792. 0+/-15.5 to 851.3+/-20.5 ms (P:<0.001). No significant changes occurred in UTR patients. Increases in BRS and RRSD were significant in patients either with or without a previous MI. CONCLUSIONS: Exercise training increases BRS and heart rate variability in patients with coronary artery disease. Improved cardiac autonomic function might add to the other benefits of exercise training in secondary prevention of ischemic heart disease.

C-reactive protein is increased in patients with degenerative aortic valvular stenosis.

OBJECTIVES: The goal of this study was to assess the presence of systemic inflammation in degenerative aortic valvular stenosis. BACKGROUND: Local inflammatory changes, resembling those observed in atherosclerosis, have been recently reported in degenerative aortic valvular stenosis. It is presently unknown whether systemic signs of inflammation, similar to those observed in atherosclerosis, may be present in this disorder. METHODS: C-reactive protein (CRP) was measured by enzyme immunoassay in 141 subjects: 62 with trileaflet degenerative valvular aortic stenosis and 79 volunteers with similar demographic and clinical characteristics. IgG antibodies against Helicobacter pylori (enzyme-linked immunosorbant assay) and Chlamydia pneumoniae (microimmunofluorescence assay) were also measured. RESULTS: C-reactive protein levels (mg/dl, mean +/- SD) were 0.848 +/- 1.42 in patients and 0.394 +/- 0.50 in controls (p = 0.0001, Mann-Whitney U test). Seroprevalence of H. pylori was 68.7% in patients and 79.7% in controls (p = NS), whereas seroprevalence of C. pneumoniae infection was higher in patients than it was in controls (59.7% vs. 33%, p = 0.003; chi-square test). After adjustment for various covariates in multiple logistic regression, the odds ratio for degenerative aortic stenosis was 3.41 for C. pneumoniae infection (95% confidence intervals [CI]: 1.60 to 7.30) and 2.76 for CRP (95% CI: 1.08 to 7.05). There was no significant difference in patients or controls in CRP levels according to the serostatus for C. pneumoniae. CONCLUSIONS: Systemic signs of inflammation, similar to those found in atherosclerosis, are present in patients with degenerative aortic valve stenosis. They do not seem to be linked to C. pneumoniae or H. pylori infection.

Helicobacter pylori duodenal colonization is a strong risk factor for the development of duodenal ulcer.

AIM: To test the hypothesis that duodenal colonization represents the final crucial step in the development of Helicobacter pylori related duodenal ulcer. METHODS: Patients with non-ulcer dyspepsia who had gastric colonization by H. pylori were included in the study. At baseline endoscopy, we evaluated the prevalence of duodenal colonization (culture, urease testing and histology), and cytotoxin-associated gene A status (polymerase chain reaction). No patients received eradication during 1 year follow-up. At this time, endoscopy was repeated and the incidence of duodenal ulcer was assessed. RESULTS: Among 181 patients completing follow-up, 53 (29%) had duodenal colonization: 72% of them were cytotoxin-associated gene A positive, versus 37% patients without duodenal colonization (P < 0.001). Duodenal ulcer developed in 12 (22.6%) patients with duodenal colonization and in two (1.6%) without duodenal colonization (odds ratio for duodenal ulcer: 6.29, 95% confidence intervals 2.44-17.45). The incidence of duodenal ulcer was similar among cytotoxin-associated gene A positive and cytotoxin-associated gene A negative subjects with duodenal colonization: 21.05% versus 26.6%. CONCLUSIONS: The assessment of duodenal colonization by H. pylori in patients with non-ulcer dyspepsia is strongly predictive for the subsequent development of duodenal ulcer and may help to stratify patients at risk for this disease.

Gene expression profiling of acute spinal cord injury reveals spreading inflammatory signals and neuron loss.

We have completed the first large-scale gene expression study of acute spinal cord injury (SCI) in rat. Oligonucleotide microarrays containing 1,200 gene-specific probes were used to quantify mRNA levels, relative to uninjured controls, in spinal cords injured using a standard contusion model. Our results revealed a marked loss of neuron-specific mRNAs at the injury site. The surviving cells showed a characteristic inflammatory response that started at the injury site and spread to the distal cord. Changes in several mRNA levels were associated with putative regenerative responses in the spinal cord. Notably, phosphodiesterase 4, nestin, glia-derived neurite promoting factor, and GAP-43 mRNAs increased significantly. Other mRNAs clustered temporally and spatially with these regeneration-associated genes. Thus we have described global patterns of gene expression following acute SCI, and we have identified targets for future study and possible therapeutic intervention.

Spontaneous baroreflex modulation of heart rate and heart rate variability during orthostatic stress in tetraplegics and healthy subjects.

OBJECTIVE: This study was addressed to investigate the contribution of vagal and sympathetic mechanisms to the genesis of low-frequency (LF) oscillations of RR-interval. DESIGN: To this aim, we utilized the pathophysiological model of tetraplegics, who have intact vagal afferent and efferent pathways of the baroreceptor reflex arc but interrupted medullary-spinal sympathetic pathways. METHODS: We studied nine complete, traumatic, tetraplegics (C4-C7, TET) and 10 normally healthy subjects (NR) at rest and during physiological baroreceptors unloading induced by 70 degrees head-up tilt. Autoregressive power spectral analysis was used to investigate RR-interval and systolic arterial pressure (SAP) variabilities. Baroreflex modulation of sinus node was assessed by the spontaneous baroreflex sequences method. RESULTS: Both at-rest and during-tilt LF and high frequency (HF) components were detected in RR-interval of NR, whereas in TET only the HF component was observed in both conditions (with one exception). Baroreflex sensitivity (BRS) did not significantly differ between TET and NR at rest, and underwent a significant and similar decrease during tilt in both groups, being accompanied in NR by a significant increase in LF relative power. Spectral analysis of SAP provided results similar to RR-interval. Tilt also slowed the centre frequency of the LF components of RR-interval and SAP. CONCLUSIONS: During unperturbed physiological conditions, a change in efferent vagal activity to the heart from baroreflex stimulation by spontaneous arterial pressure changes, is unlikely to contribute on its own to the genesis of LF heart period oscillations in humans who lack the ability to modulate sympathetic nerve traffic to the heart. However, the possibility that a baroreflex modulation of LF oscillations require an intact sympathetic control should be carefully considered.

Leucocyte rheological properties are altered in patients with diffuse atherosclerosis.

To evaluate whether atherosclerosis may be associated with altered leucocyte rheology, we assessed leucocyte count (by Coulter counter), aggregation (by means of the leukergy test) and expression of adhesion molecules integrin LFA-1 and CD 44 (by means of immunofluorescence staining and flow cytometry) in 9 patients with carotid plus lower limb artery atherosclerosis (group A), 14 patients with carotid atherosclerosis only (group B) and 23 controls without atherosclerosis (group C). The level of LFA-1 (calculated as mean fluorescence channels-MFCs) on neutrophils, lymphocytes and monocytes was significantly higher (p < 0.05) in group A and B patients than in controls (group A-mean +/- SE: 383.77 +/- 9.42 vs 295.45 +/- 5.76; 474.22 +/- 8.86 vs 388.35 +/- 7.84; 457.66 +/- 12.03 vs 396.25 +/- 4.37. Group B: 322.42 +/- 6.36 vs 295.45 +/- 5.76; 421.42 +/- 7.21 vs 388.35 +/- 7.84; 415.71 +/- 7.73 vs 396.25 +/- 4.37, respectively); furthermore, the MFC of LFA-1 on neutrophils was significantly different (p < 0.05) between group A and B patients. The percentage of aggregated leucocytes was significantly higher (p < 0.05) in group A patients (4.46 +/- 1.07) than those in groups B (1.75 +/- 0.38) and C (1.43 +/- 0.25), whereas no significant difference was detected between groups B and C. Leucocyte number and expression of CD44 were not significantly different among the 3 groups. In conclusion, changes in leucocyte rheology are present in patients with atherosclerosis and may contribute to chronic ischaemia.

Timing and course of leucocyte aggregation in myocardial infarction.

In order to evaluate the pathophysiological relevance and clinical implications of leukocyte rheology in myocardial ischaemia we measured the percentage of aggregated leukocytes in 43 subjects with acute substernal pain before diagnosis. The percentage of aggregated leukocytes was significantly higher in 16 patients with subsequent diagnosis of myocardial infarction with respect to 11 with angina and 16 with non ischaemic chest pain (4.75 +/- 0.88, 3.43 +/- 0.65 and 1.52 +/- 0.32 respectively p < 0.01). The percentage of aggregated leukocytes was also evaluated in another group of 46 patients hospitalized for myocardial infarction. Among these, aggregated leukocytes were significantly higher in those with residual ischaemia, with respect to those without residual ischaemia (7.4 +/- 1.1 vs 3.5 +/- 0.6, p < 0.01). In conclusion, leukocyte aggregation is precociously increased after myocardial ischaemia. It may be a marker of residual ischaemia in patients with myocardial infarction.

Patterns of urinary iodine excretion in a newly identified goitrous area of central Sicily.

The results of a clinical survey, relative to goiter prevalence and carried out on 2,805 male and female subjects aged from 6 to 15 years, in five small towns in the province of Caltanissetta (Sicily), are reported. Along with clinical examinations, urinary iodine determinations were performed. The identification and classification of goiter have been carried out according to criteria suggested by WHO. Considering both sexes together, 33.6% of the children presented type 1 goiter, and 4.6% presented type 2. Goiter prevalence in the five areas studied appeared to be related to the differences in the iodine content of the various drinking waters. The patterns of urinary iodine excretion, expressed as I/C ratio and derived from determinations performed on 924 of the total number of subjects examined, are reported. An analysis of these data shows that the school population as a whole, in these endemic goitrous areas, presented I/C values significantly different between goiter subjects and non-goiter subjects.

Intersexual differences in the serum-free amino acid pattern of young adults, normal obese aged subjects.

In a group of ethnically homogeneous subjects, intersexual differences and the effect of ageing on the pattern of serum free amino acid were studied. The amount of the amino acids: valine, isoleucine, leucine, tyrosine, phenylalanine, glutamic acid and ornithine was significantly greater in young males than in young females. Such intersexual differences were not observed in aged subjects. When comparing a group of aged obese females with a control group, no difference in the pattern of serum free amino acid was observed.