The acute effect of a low dosage of pramipexole on severe idiopathic restless legs syndrome: an open-label trial

BACKGROUND: Pramipexole is a D3 dopaminergic agonist that has shown a major effect on both sensory and motor manifestations of restless legs syndrome (RLS) in long-term trials. No data regarding the acute effect of low doses of pramipexole have been reported. OBJECTIVE: To evaluate the acute effect of a low dosage of pramipexole (0.125 mg) on sensory symptoms and motor signs of RLS and on the macro- and microstructure of sleep. METHODS: We initially recruited 13 patients affected by severe idiopathic RLS and included 10 of them in our study. For 2 consecutive nights the selected patients were evaluated. Pramipexole 0.125 mg was administered before the second night at 9:00 p.m. A visual analog scale was used to assess the sensory symptoms of RLS. The motor manifestations of RLS and the architecture of sleep were analyzed by polysomnography. RESULTS: After the acute administration of pramipexole, we observed a significant improvement of the sensory symptoms and motor signs of RLS. Several sleep macrostructure and microstructure parameters improved as well. CONCLUSIONS: Our results suggest that low doses of pramipexole are effective in reducing sensory symptoms and motor signs of RLS, even after the first administration.     

Aetiological agents of ventilator-associated pneumonia and its resistance pattern – a threat for treatment

Background

Ventilator-associated pneumonia (VAP) is a common type of nosocomial pneumonia encountered in intensive care units. There are several aetiological agents which make treatment challenging. Improper antibiotic treatment of ventilated patients may lead to the emergence of multidrug resistant (MDR) pathogens.

Method

A prospective study was performed over a period of 20 months. Our study had two arms: the first, ‘Incidence and risk factors of VAP in a tertiary care hospital’ was the subject of an earlier publication; we therefore present the second investigative arm in this work. The aetiological agents of patients on mechanical ventilation (MV) were identified by standard bacteriological method. The susceptibility pattern was evaluated by Kirby-Bauer disc diffusion method. Extended spectrum beta lactamase (ESBL) testing was performed by combination disc method, and metallo-beta lactamase (MBL) testing was performed by EDTA disk synergy test (EDS).

Results

Late-onset VAP was associated with Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli, while early-onset VAP was commonly caused by members of Enterobacteriaceae, Candida albicans and Staphylococcus aureus. 72.2 per cent of VAP patients had monomicrobial and 27.8 per cent had polymicrobial infection. Out of the 24 isolates obtained from patients with VAP, seven (29.2 per cent) were MDR pathogens. ESBL and MBL production was detected in 40 per cent and 20 per cent of Klebsiella pneumoniae isolated in our study. Around 50 per cent of isolates associated with late-onset VAP were MDR, while 22.2 per cent isolates obtained from patients with earlyonset VAP were MDR.

Conclusion

VAP is a nosocomial pneumonia that is common among ventilated patients. The aetiological agents vary from common organisms to MDR pathogens that are difficult to treat. A proper knowledge of MDR pathogens and early isolation followed by prevention of prolonged antibiotic therapy can reduce the mortality of late onset VAP.     

Effect of obesity on left ventricular function studied by radionuclide angiocardiography

Several studies have shown a significant association of obesity with cardiovascular morbidity and mortality. The present study was carried out to investigate central and systemic haemodynamics in overweight and moderate obese, but otherwise healthy subjects, and in a lean control group to determine whether obesity can influence left ventricular performance per se. In this study an attempt has been made to eliminate misleading factors, such as diabetes, lipid abnormalities and hypertension. A total of 67 subjects, 44 with overweight or moderate obesity and 23 lean healthy subjects, were included. Patients were divided into three groups according to BMI levels and Garrow's criteria as follows: lean control group (BMI less than 25 kg/m2); overweight (BMI from 25 to 30 kg/m2); moderate obese (BMI greater than 30 less than 40 kg/m2). Overweight and moderate obese subjects were further subgrouped according to duration of obesity (DO) in subgroup A (DO less than 98 months) and in subgroup B (DO greater than 98 months). Haemodynamic assessment was performed using first pass radionuclide angiocardiography. When compared with lean subjects, overweight and moderate obese subjects were characterized by a significant increase in cardiac output (CO), stroke volume (SV), end diastolic volume (EDV), end systolic volume (ESV), total blood volume (TBV) and total plasma volume (TPV) and by a significant decrease in left ventricular ejection fraction (EF); some of these changes appeared to be related to the degree of obesity. In overweight and moderate obese subjects, total peripheral resistance (TPR) was lower than in lean controls, but this difference was not significant.(ABSTRACT TRUNCATED AT 250 WORDS)     

Analysis of genetic instability during mammary tumor progression using a novel selection-based assay for in vivo mutations in a bacteriophage lambda transgene target.

Genetic instability is thought to be responsible for the numerous genotypic changes that occur during neoplastic transformation and metastatic progression. To explore the role of genetic instability at the level of point mutations during mammary tumor development and malignant progression, we combined transgenic mouse models of mutagenesis detection and oncogenesis. Bitransgenic mice were generated that carried both a bacteriophage lambda transgene to assay mutagenesis and a polyomavirus middle T oncogene, mammary gland-targeted expression of which led to metastatic mammary adenocarcinomas. We developed a novel assay for the detection of mutations in the lambda transgene that selects for phage containing forward mutations only in the lambda cII gene, using an hfl- bacterial host. In addition to the relative ease of direct selection, the sensitivity of this assay for both spontaneous and chemically induced mutations was comparable to the widely used mutational target gene, lambda lacI, making the cII assay an attractive alternative for mutant phage recovery for any lambda-based mouse mutagenesis assay system. The frequencies of lambda cII- mutants were not significantly different in normal mammary epithelium, primary mammary adenocarcinomas, and pulmonary metastases. The cII mutational spectra in these tissues consisted mostly of G/C-->A/T transitions, a large fraction of which occurred at CpG dinucleotides. These data suggest that, in this middle T oncogene model of mammary tumor progression, a significant increase in mutagenesis is not required for tumor development or for metastatic progression.     

Understanding APCs for nuclear cardiology

Summary  The new HCFA HOPPS with APCs is a reality. This system is an averaging and bundling system mandated by Congress and implemented by HCFA to save health care dollars and reduce patient co-payments. The BBRA allows for a 2- to 3-year transition period of continued separate payment of radiopharmaceuticals. Please review your current systems to ensure your hospital has complied with the August 1, 2000, implementation of the APC system. In addition, please continue to monitor the HCFA (www.hcfa.gov), American Society of Nuclear Cardiology (www.asnc.org), and Society of Nuclear Medicine (www.snm.org) APC link Web sites for changes to the evolving final rule, published on April 7, 2000. Any questions regarding APCs for Nuclear Cardiology can be directed to your FI, the Nuclear Medicine APC Task Force (NMAPC@snm.org) or the American Society of Nuclear Cardiology. Finally, I would like to emphasize that nuclear cardiology departments can survive and live with APCs if you code accurately. Of key importance is to know the hospital revenue in the APC system and calculate actual costs for procedures performed in the nuclear cardiology department. Thank you to the Nuclear Medicine APC Task Force members for their commitment and educational efforts regarding APCs: R. Edward Coleman, MD, Robert E. Henkin, MD, Chair, Kenneth McKusick, MD, Lynne Roy, MBA, CNMT, Gordon B. Schatz, JD, Jack J. Slosky, PhD, MBA, Ruth D. Tesar, CNMT, William Uffelman, JD, William Van Decker, MD, and Richard White, JD. Additional thanks to Gail Dauber, RN, JD, Lili Gordon, Paul Radensky, MD, JD, and Randy Van Coughnett for their unending resources and assistance in supplying the background and comments for this article.     

Intracellular mechanisms mediating the neuronal death and astrogliosis induced by the prion protein fragment 106–126

Prion encephalopathies include fatal diseases of the central nervous system of men and animals characterized by nerve cell loss, glial proliferation and deposition of amyloid fibrils into the brain. During these diseases a cellular glycoprotein (the prion protein, PrP^C) is converted, through a not yet completely clear mechanism, in an altered isoform (the prion scrapie, PrP^Sc) that accumulates within the brain tissue by virtue of its resistance to the intracellular catabolism. PrP^Sc is believed to be responsible for the neuronal loss that is observed in the prion disease. The PrP 106–126, a synthetic peptide that has been obtained from the amyloidogenic portion of the prion protein, represents a suitable model for studying the pathogenic role of the PrP^Sc, retaining, in vitro, some characteristics of the entire protein, such as the capability to aggregate in fibrils, and the neurotoxicity. In this work we present the results we have recently obtained regarding the action of the PrP 106–126 in different cellular models. We report that the PrP 106–126 induces proliferation of cortical astrocytes, as well as degeneration of primary cultures of cortical neurons or of neuroectodermal stable cell lines (GH₃ cells). In particular, these two opposite effects are mediated by the same attitude of the peptide to interact with the L-type calcium channels: in the astrocytes, the activity of these channels seems to be activated by PrP 106–126, while, in the cortical neurons and in the GH₃ cells, the same treatment causes a blockade of these channels causing a toxic effect.     

Effects of amlodipine on renal haemodynamics in mild to moderate hypertensive patients

Summary In this study the efficacy and safety of short-term amlodipine administration on renal haemodynamics were evaluated in mild to moderate hypertensive subjects. Our final goal was to evaluate whether the reduced blood pressure induced by treatment was associated with maintenance of renal function.After a run-in period with placebo, 30 hypertensive patients without cardiac or renal diseases were randomly allocated to a double-blind 4 weeks controlled study with amlodipine 10 mg once a day (15 patients) or placebo (15 patients).Renal haemodynamic measurements included effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) by radionuclide study using ¹³¹I-hippuran and ^99mTc, with methods described by Schlegel and Gates, respectively. In addition, effective renal blood flow [ERBF=ERPF/(1-Ht)], filtration fraction (FF=GFR/ERPF) ERPF) and renal vascular resistance (RVR=MBP×80/ERBF) were calculated. Plasma renin activity (PRA), serum aldosterone (ALD) and urinary excretion of sodium (NaU) were evaluated.At the end of amlodipine administration a significant decrease (P<0.001) in SBP, DBP and MBP from baseline values was observed. A significant decrease (P<0.01) in RVR and significant increases (P<0.05) in ERPF, ERBF and in NaU were also found, without relevant changes in GFR, FF, PRA and ALD.No significant variation in clinical and renal measurements was observed in the placebo group.No relevant side effects were observed in either group. In conclusion, amlodipine was effective in lowering blood pressure in mild to moderate hypertension and exerted favourable effects on renal haemodynamics and function.