Lipid peroxidation, occupational stress and aging in workers of a prehospital emergency service.

BACKGROUND: Stressful conditions lead to formation of excessive free radicals, and lipid peroxidation is one of the major outcomes of free radical-mediated injury that directly damages membranes and generates a number of secondary products. OBJECTIVES: To determine the levels of malondialdehyde, an end product of lipid peroxidation, according to demographic and occupational variables in workers of a prehospital emergency service and to analyse the relationship between malondialdehyde levels and burnout. MATERIAL AND METHODS: One hundred and eleven healthy workers of a prehospital emergency service and eighty aged-matched healthy individuals of both sexes as a control group were surveyed. Malondialdehyde levels were measured by the Bull and Marnett method. To measure burnout, the Maslach Burnout Inventory was used. RESULTS: Professional category is associated with lipid peroxidation and burnout levels (Malondialdehyde levels were: physicians 338.10+/-14.47, nurses 329.17+/-12.62 and technicians 296.74+/-14.28; burnout levels were: physicians 41.29+/-3.59, nurses 37.38+/-6.05 and technicians 35.33+/-5.87). Working at night and in the evening increased malondialdehyde and burnout levels. Malondialdehyde levels increase with age. No significant variations with respect to sex were detected. Significant variations in malondialdehyde levels were detected between singles (303.13+/-12.74) and married people (344.43+/-13.43) but not with respect to divorcees (326.44+/-11.74). Significant differences were detected in erythrocyte malondialdehyde levels between smokers (341.37+/-17.09) and nonsmokers (302.21+/-12.38), but not for alcohol consumption. CONCLUSIONS: These findings suggest a positive correlation between malondialdehyde, a biomarker of lipid peroxidation and occupational stress, as estimated by elements of the Maslach Burnout Inventory, and oxidative stress.     

Histological and biological developmental characterization of the human cerebellar cortex

The aim of this study was to investigate the histological and biological features of the human cerebellar cortex development and differentiation. We analyzed 52 brains of fetal and infant death victims, aged from 17 gestational weeks to 12th postnatal month. In particular, in the cerebellar cortex at different ages we evaluated, besides the structural aspects, the expression of several biomarkers implicated in proliferative processes (c-fos, PCNA and apoptosis). We observed morphological patterns progressively evolving every month, from the indefinite structure of the second gestational trimester to the four-layered structure (external granular layer, molecular layer, Purkinje cell layer, internal granular layer) of the late fetal cortex and subsequently to the three-layered postnatal definitive morphology, due to involution of the external granular layer. The evaluation of the biological features of the cerebellar cortex showed high proliferative activity mainly confined to the transient external granular layer in prenatal life, and high apoptotic index after birth. Thus, the histological examination, better with the support of biomarker investigations, allows with accuracy to describe the dynamic sequence of steps that occur in human cerebellar cortex development and to establish in each case the age, namely the pre- or postnatal month of life. Consequently, we can diagnose delayed or altered processes of differentiation during the development of the human cerebellar cortex.     

Do phonologic and rapid automatized naming deficits differentially affect dyslexic children with and without a history of language delay? A study of Italian dyslexic children.

OBJECTIVE: The study aims to verify whether phonologic and rapid automatized naming (RAN) deficits are present and associated in Italian dyslexic children and whether they differentially affect dyslexics with and without a history of previous language delay (LD). BACKGROUND: According to the phonologic core deficit hypothesis, dyslexia may stem from impairment of the representation and manipulation of phonemes and may be closely associated with oral language deficits. However, deficits in tasks not requiring fine-grained phonologic representations, such as RAN, have also been described in dyslexic children. METHODS: Thirty-seven children were selected on the basis of a reading deficit and were assigned to 2 groups according to whether or not they had a history of early LD as determined retrospectively by parental report. A battery of reading and writing, verbal working memory, metaphonologic, RAN, and visual search tests were administered. RESULTS: RAN deficits were shared by most dyslexics (with and without a history of LD), whereas phonologic deficits were mainly associated with a previous LD. This last condition did not result in a more profound impairment of reading and writing decoding skills. CONCLUSION: In a shallow orthography such as Italian, RAN, not phonologic deficits, may represent the main cognitive marker of developmental dyslexia.     

Reproducibility of Computerized Measurements of QT Interval from Multiple Leads at Rest and During Exercise

Background: Accurate measurement of the QT interval is important for diagnosing long QT syndrome (LQTS), and in research on determinants of ventricular repolarization time. We tested automatic analysis of QT intervals from multiple ECG leads on chest. Methods: Eleven healthy volunteers and 10 genotyped LQTS patients were tested at rest and during exercise with a bicycle ergometer twice 1–31 months apart. Electrocardiograms were recorded with the body surface potential mapping system, and 12 precordial channels were selected for analysis. Averaged QT peak and QT end intervals were determined with an automated algorithm, and the difference QT end minus QT peak (Tp‐e) was calculated. Repeatability was assessed by coefficient of variation (CV) between measurements. Results: Within one test at rest the QT end intervals were highly repeatable with CV 0.6%. In repeated tests CV was 4.4% for QT end interval and 3.5% when the QT interval was corrected for heart rate. In exercise test at specified heart rates, mean CV was 3.0% for QT end and 2.9% for QT peak interval. The CV of Tp‐e interval was 10.2% at rest, and 9.3% in exercise test. Reproducibility was comparable between healthy subjects and LQTS patients. Conclusions: The BSPM system with automated analysis produced accurate and highly repeatable QT interval measurements. Reproducibility was adequate also over prolonged time periods both at rest and in exercise stress test. The method can be applied in studying duration of ventricular repolarization time in different physiologic and pharmacologic interventions.     

Analysis of renal function in the immediate postoperative period after partial liver transplantation.

Although renal dysfunction is common after liver transplantation, postoperative renal function after split liver transplantation (SLT) has not been well studied. Renal function immediately after surgery was analyzed retrospectively in 16 patients that received a SLT (SLT group). The results were compared with corresponding data from 31 matched patients that received a full-size liver transplant (FSLT group) during the same period. Serum creatinine (SCr) was measured before surgery, and, after transplantation, daily during the first week and at days 14, 21, and 28. Renal dysfunction (RD) was defined as the requirement for renal replacement therapy (RRT) or a 100% increase in SCr if the basal value had been <1.0 mg/dL or a 50% increase in SCr if the basal value had been >1.0 mg/dL. SCr had to be at least 1.5 mg/dL for a diagnosis of RD to be considered. The classification of RD was: mild, SCr 1.5-2.4 mg/dL; moderate, SCr 2.5-4.0 mg/dL; or severe, SCr >4.0 mg/dL (the requirement for RRT). Both donor and recipient age and cold ischemia time were lower in the SLT group than in the FSLT group (P < 0.05). Length of surgery was longer in the SLT group (P < 0.05). There were no significant differences between groups with respect to Model for End-Stage Liver Disease scores, the need for transfusions, the length of admission to the intensive care unit (ICU), survival rate, individual severity index, or sepsis-related organ failure assessment scores at the time of diagnosing RD. Immunosuppression regimens were similar in both groups. RD developed in 82% of SLT patients, but in only 58% of FSLT patients (P = not significant [NS]). Among SLT patients, RD (23.0% mild, 15.5% moderate, and 61.5% severe) was more severe (P = 0.007) than in FSLT patients (63.1% mild, 15.8% moderate, and 24.1% severe). The requirement for RRT in the SLT group (43.7%) was significantly greater (P < 0.05) than that in the FSLT group (12.9%). This finding may be due to the different incidence of sepsis in the 2 groups (SLT 37.5% vs. FSLT 9.7%; P < 0.05). In conclusion, although the number of patients studied was small, our data suggest a higher incidence of RD and a greater requirement for RRT in patients that receive a split liver graft than in those that receive a full size liver graft.     

Safety considerations for operating room personnel during hyperthermic intraoperative intraperitoneal chemotherapy perfusion.

The new treatment strategy for Peritoneal Surface Malignancy combines a cytoreductive surgery and perioperative intraperitoneal chemotherapy. Cytoreduction removes all macroscopic tumor. Intraperitoneal chemotherapy avoids implantation of microscopic residual tumor cells on intra-abdominal surfaces when it is administered intraoperatively and/or early in the postoperative period. Delivering cytotoxic drugs directly into the peritoneal cavity maximizes dose intensity and minimizes systemic toxicity. Hyperthermia is selectively cytotoxic for malignant cells and potentiates the effect of chemotherapy. Implementation of this procedure makes the perioperative personnel to face a risk of exposure to cytotoxic agents. Furthermore, peritonectomies and electro-evaporation of tumor nodules are performed with high voltage electrocautery, generating a large amount of surgical smoke during several hours. Inhalation of these fumes may be also a risk for healthcare workers. In this article, we analyse in depth these new risks of the operating room personnel, we review the literature, and we give guidelines for secure performance of cytoreductive surgery and hyperthermic intraoperative intraperitoneal chemotherapy, as well as for early postoperative intraperitoneal chemotherapy administration. These new procedures are safe techniques for patients and healthcare workers provided adequate policies are adopted to avoid occupational exposure.     

Blunted renal dopaminergic system activity in puromycin aminonucleoside-induced nephrotic syndrome.

BACKGROUND: A primary tubular sodium handling abnormality has been implicated in the edema formation of nephrotic syndrome. Dopamine synthesized by renal proximal tubules behaves as an endogenous natriuretic hormone by activating D(1)-like receptors as a paracrine/autocrine substance. METHODS: We examined the time courses of the urinary excretion of sodium, protein and dopamine in puromycin aminonucleoside (PAN)-treated and control rats. The rats were sacrificed during greatest sodium retention (day 7) as well as during negative sodium balance (day 14) for the evaluation of renal aromatic l-amino acid decarboxylase (AADC) activity, the enzyme responsible for the synthesis of renal dopamine. Also, the influence of volume expansion (VE) and the effects of the D(1)-like agonist fenoldopam (10 microg/kg bw/min) on natriuresis and on proximal tubular Na(+),K(+)-ATPase activity were examined on day 7. RESULTS: The daily urinary excretion of dopamine was decreased in PAN-treated rats, from day 5 and beyond. This was accompanied by a marked decrease in the renal AADC activity, on days 7 and 14. During VE, the fenoldopam-induced decrease in proximal tubular Na(+),K(+)-ATPase activity was more pronounced in PAN-treated rats than in controls. However, the urinary sodium excretion during fenoldopam infusion was markedly increased in control rats but was not altered in PAN-treated animals. CONCLUSION: PAN nephrosis is associated with a blunted renal dopaminergic system activity which may contribute to enhance the proximal tubular Na(+),K(+)-ATPase activity. However, the lack of renal dopamine appears not to be related with the overall renal sodium retention in a state of proteinuria.     

Serum leptin concentrations in pre- and postmenopausal women on sex hormone therapy.

AIM: The aim of the present study was to investigate the influence of endogenous estradiol and estrogen and estrogen-progestin therapies on concentration in pre- and postmenopausal women. MATERIALS AND METHODS: The study groups consisted of 26 women with surgical menopause (mean+/-standard deviation (SD): age 51.8+/-2.6 years, body mass index (BMI) 26.45+/-4.56 kg/m(2)), 54 with natural menopause (mean+/-SD: age 50.5+/-3.0 years, BMI 25.75+/-4.09 kg/m(2)) and 40 premenopausal controls (mean+/-SD: age 48.3+/-2.3 years, BMI 26.23+/-4.12 kg/m(2)). The group with surgical menopause received estradiol transdermally (50 microg/day) and those with natural menopause received additionally medroxyprogesterone acetate (5 mg/day) for the last 12 days of the cycle. Before and after 4 months of therapy, body weight, waist and hip circumferences and blood pressure were measured, and BMI and waist-to-hip ratio (WHR) were calculated. Serum leptin, follicle-stimulating hormone (FSH), estradiol (E(2)), testosterone, prolactin and dehydroepiandrosterone sulfate (DHEAS) were measured prior to and after treatment. RESULTS: Leptin concentrations did not differ statistically among the groups. No correlations between leptin and E(2), FSH, prolactin, testosterone and DHEAS concentrations were found in any of the groups before and after treatment. Leptin level correlated positively with body mass, BMI and hip and waist circumferences in all groups. There were no correlations between leptin and WHR in the pre- and postmenopausal groups. In the premenopausal group and in some postmenopausal groups, serum leptin level correlated with blood pressure. CONCLUSIONS: Endogenous E(2) and androgens in premenopausal women and estrogen and estrogen-progestin therapies in postmenopausal subjects do not influence serum leptin concentrations. Leptin level is related to body mass and BMI, but not to sex hormone status. The distribution of adipose tissue and the type of obesity (android or gynoid) have no influence on serum leptin concentration. The correlation between serum leptin level and blood pressure requires further investigation.