Night-to-night variability of objective sleep outcomes in youth Middle Eastern football players

OBJECTIVE

To describe components of night-to-night variation in objective measures of sleep.

METHODS

We conducted a secondary data analysis of consecutive and chronologically ordered actigraphy-based measurements for time in bed (min), time asleep (min), and wake-after-sleep onset (min). This investigation examined 575 individual night-based measures available for a sub-sample of fifty-two, male youth Middle Eastern football players tracked over a 14-day surveillance period (chronological age range: 12.1 to 16 years). Distinct multivariable-adjusted generalized additive models included each objective sleep outcome measure as dependent variable and disaggregated components of variation for night measurement-by-sleep period interaction, week part (weekday or weekend), and study participant random effects from within-subject night-to-night sleep variation.

RESULTS

The within-subject standard deviation (SD) of ±98 min (95% confidence interval [CI], 92 to 104 min) for time in bed, ±87 min (95%CI, 82 to 93 min) for time asleep, and ±23 min (95%CI, 22 to 25 min) for wake-after-sleep-onset overwhelmed other sources of variability and accounted for ∼44% to 53% of the overall night-to-night variation. The night measurement-by-fragmented sleep period interaction SD was ±83 min (95%CI, 44 to 156 min) for time in bed, ±67 min (95%CI, 34 to 131 min) for time asleep, and ±15 min (95%CI, 7 to 32 min) for wake-after-sleep-onset that accounted for ∼22% to 32% of each sleep outcome measure overall variability.

CONCLUSIONS

Substantial random night-to-night within-subject variability poses additional challenges for strategies aiming to mitigate problems of insufficient and inconsistent sleep that are detrimental to school learning and youth athlete development processes.

Age-Related Reference Intervals for Physical Performance Test Outcomes Relevant to Male Youth Middle Eastern Football Players

PURPOSE

To develop age-specific reference intervals for physical performance test outcomes relevant to male youth Middle Eastern football players.

METHODS

We analyzed mixed-longitudinal data (observations range: 1751-1943 assessments) from a sample of 441 male youth outfield football players (chronological age range: 11.7-18.4 y) as part of the Qatar Football Association and Aspire Academy development program over 14 competitive seasons. Semiparametric generalized additive models for location, scale, and shape estimated age-specific reference centiles for 10-m sprinting, 40-m sprinting, countermovement jump height, and maximal aerobic speed variables.

RESULTS

The estimated reference intervals indicated that the distribution of the physical performance test scores increased monotonically and nonlinearly with advancing chronological age for sprinting and countermovement jump outcome measures, reaching a plateau after 16 years common to each of these performance variables. The maximal aerobic speed median score increased substantially until ∼14.5 years, with the nonlinear trend flattening off toward relatively older chronological ages.

CONCLUSIONS

We developed age-related reference intervals for physical performance test outcomes relevant to youth Qatari football players. Country-wide age-specific reference intervals can assist in the longitudinal tracking of the individual players' progress over time against benchmark values derived from the reference population.

A survey of organizational structure and operational practices of elite youth football academies and national federations from around the world: A performance and medical perspective

Aim

Medical and performance units are integral components of player development programmes in elite football academies. Nevertheless, the nature of the operational processes implemented by practitioners within clubs and national federations remains unexplored. The aim of the present study, therefore, was to survey elite youth professional football academies from around the world regarding the operational processes adopted by their medical and performance units.

Methods

Of the 50 organizations invited, 10 national federations and 25 clubs took part in the survey resulting in a response rate of 70% (95% confidence interval, 56%-81%). The respondents represented three groups: senior club and academy management, performance, and medical staff.

Results

The majority (60%-90%) of clubs and national federations reported strategic alignment between senior and academy medical and performance units as well as between academy medical and performance units. Survey responses indicated substantial heterogeneity in the composition and number of medical and performance professionals employed in academies. The majority of respondents agreed their medical and performance departments were effective in utilizing staff knowledge and external sources of knowledge to inform their practice (56%-80%). Performance staff (40%-50%) and physiotherapists (30%-32%) were deemed most influential in injury prevention programmes. During the return-to-play process, the influence of specific practitioners in the medical and performance units was dependent upon the phase of return-to-play. Shared decision-making was common practice amongst performance and medical staff in injury prevention and return-to-play processes. Medical and performance data were generally centralized across the first team and academy in majority (50%-72%) of clubs and national federations. Data were integrated within the same data management system to a higher degree in clubs (68%) vs. national federations (40%). Research and development activity were reported for most academies (50%-72%), and generally led by the head of performance (37%) or team doctor (21%). Research activities were largely undertaken via internal staff (~100%), academic collaborations (50%-88%) and/or external consultants and industry partnerships (77%-83%) in the national federation and clubs.

Conclusion

Collectively, these findings provide a detailed overview regarding key operational processes delivered by medical and performance practitioners working in elite football academies.

An objective description of routine sleep habits in elite youth football players from the Middle-East

BACKGROUND AND STUDY OBJECTIVES

Adequate sleep is essential to support preparation and recovery processes for training and competition in athletes. A limited number of studies have examined whether adolescents from the Middle-East meet the minimum age-specific recommendations ranging from 8 to 9 h of night sleep based on objective measurements. This study aimed to provide an objective description of routine sleep habits in elite youth football players from the Middle-East.

METHODS

Using wrist-worn actigraphy, we examined objective measures of sleep over a 14-day surveillance period from fifty-nine, male, Middle-Eastern elite youth football players (age range: 12.1 to 16 years).

RESULTS

The observed median sleep duration was approximately 5.5 to 6 h during weekdays and 6.5 to 7.5 h over weekend days. Sleep intermissions resulting in two or more periods of sleep accounted for 8% and 17% of the data during weekdays and weekends, respectively.

CONCLUSIONS

For the first time, we reported an objective quantification of sleep measures indicating that elite youth athletes from the Middle-East do not meet the age-specific sleep recommendations. Integration of sleep tracking into the routine training monitoring process can be valuable to inform decisions relevant to the adoption of potential multidisciplinary interventions to address sleep insufficiency and disorders in youth athletes.

No association between perceived exertion and session duration with hamstring injury occurrence in professional football

Training and competition loads have emerged as modifiable composite risk factors of non-contact injury. Hamstring strains are the most common injuries in football with substantial burden on the individual player and club. Nevertheless, robust evidence of a consistent load-hamstring injury relationship in professional football is lacking. Using available data from the Qatar Stars League over three competitive seasons, this study investigated the separate and combined effects of perceived exertion and session duration on hamstring injury occurrence in a sample of 30 outfield football players. Load variables were calculated into 7-day, 14-day, 21-day, 28-day periods of data, and week-to-week changes for average ratings of perceived exertion (RPE; au) score and session-RPE (s-RPE; session-duration  ×  score), plus the cumulative training and match minutes and s-RPE, respectively. Conditional logistic regression models estimated load-injury relationships per 2-within-subject standard deviation increments in each candidate variable. Associations were declared practically important based on the location of the confidence interval in relation to thresholds of 0.90 and 1.11 defining small beneficial and harmful effects, respectively. The uncertainty for the corrected odds ratios show that typically high within-subject increments in each candidate variable were not practically important for training- and match-related hamstring injury (95% confidence intervals range: 0.85 to 1.16). We found limited exploratory evidence regarding the value of perceived exertion and session duration as etiological factors of hamstring injury in Middle-East professional football. Monitoring remains valuable to inform player load management strategies, but our exploratory findings suggest its role for type-specific injury risk determination appears empirically unsupported.

The nuclear matrix elements of 0νββ decay and the NUMEN project at INFN-LNS

The goal of NUMEN project is to access experimentally driven information on Nuclear Matrix Elements (NME) involved in the neutrinoless double beta decay (0νββ), by high-accuracy measurements of the cross sections of Heavy Ion (HI) induced Double Charge Exchange (DCE) reactions. The knowledge of the nuclear matrix elements is crucial to infer the neutrino average masses from the possible measurement of the half-life of 00νββ decay and to compare experiments on different isotopes. In particular, the (18O, 18Ne) and (20Ne, 20O) reactions are performed as tools for β+β+ and β-β- decays, respectively. The experiments are performed at INFN - Laboratory Nazionali del Sud (LNS) in Catania using the Superconducting Cyclotron (CS) to accelerate the beams and the MAGNEX magnetic spectrometer to detect the reaction products. The measured cross sections are very low, limiting the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. In order to make feasible a systematic study of all the candidate nuclei, a major upgrade of the LNS facility is foreseen to increase the experimental yield of about two orders of magnitude. To this purpose, frontier technologies are going to be developed for both the accelerator and the detection systems. In parallel, advanced theoretical models will be developed to extract the nuclear structure information from the measured cross sections.

Influence of 5-Fluorouracil and Folinic Acid on Interleukin-18 Production in Colorectal Cancer Patients

Aims and Background

This study was carried out to evaluate the IL-18 blood concentrations of operated colorectal cancer patients and their possible variation in response to combination chemotherapy with 5-fluorouracil (5-FU) and folinic acid.

Methods

IL-18 levels were assayed in sera of 18 healthy donors and 18 surgical colorectal cancer patients before and after adjuvant chemotherapy with 5-fluorouracil and folinic acid. An ELISA kit for human IL-18 was used for the assay.

Results

Colorectal cancer patients showed significantly higher baseline levels of IL-18 than healthy donors (p<0.005). Furthermore, serum IL-18 levels increased significantly with respect to baseline in patients receiving adjuvant chemotherapy (p<0.005).

Conclusions

This study suggests that treatment with 5-fluorouracil and folinic acid may provoke an increase in IL-18 serum levels in colorectal cancer patients. This increase may help to explain the efficacy of adjuvant chemotherapy with 5-FU in colorectal cancer.

Prevalence and Correlates of Anemia and Uncontrolled Anemia in Chronic Hemodialysis Patients – The Campania Dialysis Registry

Background

This study investigated prevalence and correlates of anemia and uncontrolled anemia in chronic hemodialysis patients.

Methods

A cross-sectional analysis was performed on registry data for 2,746 chronic (<6 months) hemodialysis patients aged 25–84. Data collection included years of dialysis, hours of dialysis/wk, disease causing hemodialysis, body mass index (BMI), erythropoietin (EPO) treatment, hemoglobin, markers of viral hepatitis, serum albumin, calcium, and phosphorus.

Results

Prevalence was 88.7% for anemia (hemoglobin <11 g/100 mL and EPO treatment at any Hb level), 39.4% for uncontrolled anemia (hemoglobin<11 g/100 mL). Gender, years of dialysis, hereditary cystic kidney disease (HCKD), and low BMI (<24 kg/m2) were independent correlates of anemia (P<0.001). Gender, HCKD, low BMI, serum albumin and calcium were independent correlates of uncontrolled anemia (P<0.05). An interaction was found between age (not correlated with anemia and uncontrolled anemia) and the association of gender with uncontrolled anemia (P<0.05). EPO doses were higher in patients with high prevalence of uncontrolled anemia than in patients with low prevalence (i.e., women vs men, other diseases vs HCKD, low vs not-low BMI, P<0.01). Gender, years of dialysis, HCKD, BMI, serum albumin, and calcium were independent correlates of the hemoglobin/EPO dose ratio in patients on EPO treatment (P<0.05).

Conclusion

Anemia and uncontrolled anemia are more frequent in hemodialysis patients with short-term dialysis, diseases other than HCKD, low BMI, and female gender. Gender effect was lower in elderly patients. Uncontrolled anemia was also associated with low serum albumin and calcium, suggesting that these parameters are indices of EPO resistance.

[The role of anti-nucleosome antibodies in systemic lupus erythematosus. Results of a study of patients with systemic lupus erythematosus and other connective tissue diseases]

OBJECTIVE

The aim of our study was to investigate the prevalence and the disease specificity of anti-nucleosome antibodies in systemic lupus erythematosus and their association with disease activity and renal involvement.

METHODS

Anti-nucleosome antibodies were measured by ELISA in the sera of patients with systemic lupus erythematosus (SLE) (47), rheumatoid arthritis (RA) (22), mixed connective tissue disease (MCTD) (19), systemic sclerosis (SSc) (11) and Sjögren's syndrome (SS) (10). Anti-dsDNA antibodies were measured by IIF on Crithidia luciliae. In the patients with SLE serum levels of C3 and C4 complement components were also measured. Sera of 22 healthy individuals were assayed as controls. SLE activity was evaluated by the ECLAM score.

RESULTS

Anti-nucleosome antibodies were found in 40 patients with SLE (85.1%), in 10 with RA (45.4%), in 8 with MCTD (42.1%), in 4 with SSc (36.3%), in 1 with SS (10%) and in none of the healthy controls. Anti-dsDNA antibodies were found in 23 patients with SLE and were absent in the patients with other CTD and in controls. All the patients with SLE and renal involvement were positive both for anti-dsDNA antibodies and anti-nucleosome antibodies. No significant correlation was observed between anti-nucleosome antibodies and disease activity and renal involvement.

CONCLUSION

Anti-nucleosome antibodies are present in a high percentage of the patients with SLE but they don't seem to be specific markers of the disease. Our data don't support a clear correlation between anti-nucleosome antibodies and disease activity and renal involvement.

Specific detection of Arcobacter spp. in estuarine waters of Southern Italy by PCR and fluorescent in situ hybridization

AIM

To evaluate the reliability of culture-independent methods in comparison with culture-dependent ones for the detection of Arcobacter spp. in estuarine waters of Southern Italy.

METHODS AND RESULTS

PCR and fluorescent in situ hybridization (FISH) procedures were used to detect arcobacters directly in water samples and after enrichment cultures. The samples totally were positive by molecular methods (PCR and FISH) but only 75% were culture positive, confirming the limitation of these latter to detect Arcobacter spp. in natural samples. Culturable arcobacters were retrieved in all times except in July, and isolated species were ascribed only to Arcobacter cryaerophilus.

CONCLUSIONS

Culturable and nonculturable forms of Arcobacter in the estuarine environment were present. PCR assays were more sensitive than traditional culture in detecting Arcobacter butzleri and A. cryaerophilus. FISH comparatively to PCR technique may provide information about cell morphology and viability of single cells.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our investigation indicates the existence of an environmental reservoir of potential pathogenic arcobacters in an estuarine Italian area, which may survive under a viable but not culturable state.

Dysregulation of Emotions and Premature Ejaculation (PE): Alexithymia in 100 Outpatients

INTRODUCTION

There is still a lack of agreement on etiology, definition, and mechanisms that underlie premature ejaculation (PE) as well as on the different role and interaction between psychological and biological factors. Alexithymia is a deficit in identifying and communicating emotions that is presumed to play an important role in psychosomatic diseases. The influences of alexithymic features on sexuality are still understudied.

AIM

Following a previous report on the relationship between alexithymia and erectile dysfunction, the objective of this study was the investigation of alexithymic features in patients with lifelong PE compared with controls, and the relationship between alexithymia level and PE severity.

METHODS

We assessed 100 consecutive outpatients with lifelong PE (age range 20-60). A control group of 100 male volunteers was recruited for the control group. The two groups were comparable in age, marital status, and socioeconomic characteristics.

MAIN OUTCOME MEASURES

The Toronto Alexithymia Scale (TAS-20) was employed for the assessment of alexithymia. The premature ejaculation severity index was used as self-report measure of PE severity on a multidimensional perspective.

RESULTS

Our data show significantly higher scores of alexithymia in patients with PE than in the control group (P < 0.001), and a positive correlation between alexithymia level and PE severity (P < 0.002). With regard to TAS-20 subfactors, an externally oriented cognitive style shows the highest correlation with PE severity (P < 0.001) and the most significant difference in the comparison between PE and control group (P < 0.001).

CONCLUSION

These findings suggest that alexithymic features, and in particular, an externally oriented cognitive style, can be seen as possible risk and/or maintenance factors for PE, and may contribute to a more serious manifestation of this condition. Alexithymia could represent an important variable for an integrated diagnosis and treatment of PE in a modern somatopsychic and holistic viewpoint.

Male sexuality and regulation of emotions: a study on the association between alexithymia and erectile dysfunction (ED)

Alexithymia is a multidimensional construct that describes a constellation of personality features characterised by difficulties in differentiating, identifying and communicating emotions. The purpose of the present study was to investigate prevalence of alexithymia in outpatients with erectile dysfunction (ED), both in the psychogenic lifelong type (PLED) and in the acquired one (PAED). ED severity was evaluated with the International Index of Erectile Function (IIEF) and alexithymia was measured using the Italian version of the 20-item Toronto Alexithymia Scale (TAS-20). The results suggest a high incidence of alexithymic characteristics in patients with psychogenic ED, a positive correlation between the alexithymia level and ED severity in patients with PAED and statistically significant differences in the alexithymia level between the two subgroups PLED and PAED. We assumed that alexithymia contributes to the origin of the PLED, and to a more severe manifestation of ED, once it appears in the acquired form.

Cerebral vasculitis in a patient with HCV-related type II mixed cryoglobulinemia

The peripheral nervous system is often involved in patients with mixed cryoglobulinemia (MC), while there are few reports of central nervous system involvement. We describe a case of HCV-related type II MC with peripheral and central nervous system involvement. A 61-year-old woman, suffering from flaccid tetraparesis, was referred to our department because of an increasing disability. The presence of delirium prompted us to also investigate the central nervous system. MMSE, EEG, EMG, brain CT-scan, color-Doppler of neck vessels, retinal fluorangiography and brain MRI were performed. These investigations suggested a cerebral vasculitis. The finding of very low C4 serum levels, together with high rheumatoid factor serum levels, suggested the search for cryoglobulins. The laboratory findings showed a HCV-related type II (IgMk) MC. A marked improvement of symptoms and of laboratory data was obtained by treatment with methylprednisolone + cyclophosphamide.

[Idiopathic hypereosinophilic syndrome associated with rheumatoid arthritis. A case report]

The idiopathic hypereosinophilic sindrome (HES) is a disease characterized by persistent blood eosinophilia (> 1500 eosinophils/mm3 > 6 months) -in absence of other ethiologies for eosinophilia (parasitic, allergic, immunological or malignant diseases)- associated with multiple organ involvement (heart, lung, central nervous system, skin, bone marrow, gastrointestinal tract). Reports on rheumatologic manifestations in patients with HES are very rare. In the case we report a typical rheumatoid arthritis developed in a 58-year-old woman with HES treated with glucocorticoids. Because of the marked glucocorticoids side effects shown by the patient (cushingoid habitus, hyperglycemia), we stopped this treatment and replaced it at first by methotrexate and later by cyclosporin, both of them associated with sulfasalazine. These drugs revealed very efficacious both on articular pathology and on the clinical and laboratory manifestations of HES. These data suggest that common pathogenetic mechanisms are likely acting in rheumatoid arthritis and idiopathic hypereosinophilic syndrome.

Does the ICD 10 classification accurately describe subtypes of borderline personality disorder?

The aim of the paper is to explore whether the division of borderline personality disorder, as described in the DSM classification, into impulsive and borderline subtypes of emotionally unstable personality disorder in the ICD classification of personality disorder, is a valid division. The self-report questionnaire responses of 288 referrals to a personality disorder service were rated on each of the eight criteria for DSM-III-R diagnosis of borderline personality disorder. Factor analysis identified two factors; factor one closely corresponds with the borderline subtype of ICD10, whilst factor two closely corresponds with the impulsive subtype of ICD10. Criteria common to both factors unstable relationships and identity confusion - were considered core features of borderline personality disorder. The pattern of occurrence of the two factors was similar to the complex binary picture described by ICD10. However there were also differences. Firstly, identity confusion is found to be a core feature of both our factors, and this does not conform to the restriction of identity confusion to the borderline subtypes in ICD10. Secondly, we found a residual pool of undifferentiated borderline patients and a small group of pure non-impulsive borderline patients who are not currently accommodated within the ICD10 emotionally unstable personality disorder. We conclude that future classifications of this disorder should accommodate four subtypes, and suggest these subtypes have implications for treatment and further research.

[Anticardiolipin antibodies in hemodialysis patients and in renal transplant recipients: prevalence and significance]

Increased anticardiolipin antibodies (aCL) serum levels have been recently described in haemodialysis patients and in renal transplant recipients, with a prevalence ranging from 4.8 to 46.4%. The causes and the clinical significance of aCL positivity in these patients are uncertain. We measured IgG- and IgM-aCL serum levels in 61 haemodialysis patients, in 14 renal transplant recipients and in 38 healthy controls. Increased levels of IgG-aCL were found in 4 haemodialysis patients (6.55%), in 2 transplant patients (14%) and in 2 of the healthy controls (5.26%). IgM-aCL serum levels were normal in all the patients. After one year of follow-up, no vascular events have been observed in aCL positive patients. It is probable that the presence of aCL in the serum of patients with end-stage renal disease is only an epiphenomenon and does not play a pathogenetic role.

[High levels of blood IgA in patients with rheumatoid arthritis]

MATERIALS AND METHODS

Serum levels of IgA, IgG and IgM were measured in 46 patients (34 women, 12 men) with rheumatoid arthritis. The duration of the disease ranged from 6 months to 30 years; the patients follow-up ranged from 6 months to 12 years.

RESULTS

Serum IgA levels higher than the normal (> 450 mg/dl) were found in 20 patients (43.4%). These patients had mean levels of IgG, C3c and erythrocyte sedimentation rate significantly higher than the patients with normal IgA levels.

CONCLUSIONS

A significant relationship between the IgA levels and the activity of the disease or its clinical and radiological features was not observed. On the other hand, a relationship was observed between IgA levels and the mean duration of the disease which was significantly more prolonged in patients with high IgA serum levels.

[Connections between ischemic heart disease and anti-cardiolipin antibody positivity]

IgG and IgM anti-cardiolipin antibodies (aCL) were measured in 60 patients with ischaemic heart disease by an immunoenzymatic assay. aCL levels higher than normal were detected in 12 of 40 patients (30%) with acute myocardial infarction (AMI) and in 7 of 20 patients (35%) with angina pectoris (AP). These values were significantly higher (p < 0.05) than those detected in the control group (3/40; 7.5%). As regards the clinical picture, the complications and the outcome of the disease, no difference was observed between aCL-positive and negative patients with AMI. 9 of 12 aCL-positive patients with AMI showed increased levels of aCL in a blood sample obtained in day 1 after admission. Therefore, we must admit such positivity as preexistent to the myocardial infarction. These data together with the high prevalence of aCL in patients with AP suggest that an association should exist between raised levels of aCL and increased risk for AMI in patients with coronary artery disease.

[Presence and significance of anticardiolipin antibodies in infectious diseases]

IgG and IgM anti-cardiolipin antibodies were measured, by an ELISA technique, in the sera of patients with B hepatitis (28), infectious mononucleosis (10), chicken pox (12), HIV infection (20), acquired toxoplasmosis (41) and other infectious diseases [HBsAg+ chronic hepatitis (5), brucellosis (6), herpes zoster (4), boutonneuse fever (3), viral pneumonitis (4), rheumatic fever (2)]. Increased levels of anti-cardiolipin antibodies (aCL), at least in one immunoglobulin class, were detected in 37 out of 135 patients [27.4%; range: 7.3% (in the patients with toxoplasmosis) -80% (in the patients with HIV infection)]. Low or medium titer aCL were present in 28 patients, high titer in 9 (6 with HIV infection, 2 with chicken pox and I with lymphoadenopathic toxoplasmosis). None of the manifestations associated with aCL was present in the aCL-positive patients. Finally, positivity for aCL didn't seem to modify the clinical picture and the prognosis of the infectious disease.

[Clinical contribution to the problem of correlations between hereditary angioneurotic edema and pregnancy]

Hereditary angioneurotic edema (HAE) is an autosomal dominant disease caused by a deficiency of a complement regulatory protein, the C1INH.HAE is clinically characterized by recurrent, self-limited attacks of edema involving the extremities, face, upper respiratory tract or gastrointestinal tract. Pregnancy in a woman affected by HAE poses therapeutical problems. In fact, prophylactic treatment with danazole or tranexamic acid is control indicated in a pregnant woman. However HAE shows a favourable course in most cases and the delivery, despite the local trauma, is not usually associated with complications. But the occasional occurrence of local edema and the literature report of a death in postpartum, suggest the administration of purified C1INH prophylactically before the delivery. HAE, per sé, neither alters the evolution of pregnancy nor does foetus harm. The A. report on a 22-years old primigravida affected by HAE. She had no attack during the whole gestation, the delivery and the postpartum. She was given 1000 units of purified C1INH concentrate both four hours before the delivery and 24 hours after it.

Effects of PGE2 infusion on renal function in normal man before and after angiotensin II inhibition by captopril

Increasing doses of prostaglandin E2 (PGE2) (5, 10, 20, 40, 60 ng/kg/min) were infused in 7 normal volunteers before and after angiotensin II synthesis inhibition by captopril (100 mg by mouth). PGE2 infusion alone did not alter blood pressure, while it increased the urinary excretion of both epinephrine and norepinephrine, enhanced p-aminohyppuric clearance (CPAH), inulin clearance (CIn), sodium and water excretion and decreased urinary osmolality. No changes of CIn, CPAH and catecholamines were observed after captopril alone, whilst there was a significant increase in urine output and sodium excretion and a decrease in urinary osmolality. In the presence of captopril, the infusion of PGE2 caused a significant fall in blood pressure and CIn, enhanced epinephrine excretion and sodium excretion, while it did not significantly reduce CPAH. Our findings suggest that an intact renin-angiotensin system is necessary to maintain GFR during PGE2 infusion.