The effect of multiple stimuli on the modulation of the 'nociceptive' blink reflex

The 'nociceptive' blink reflex is a method of examining human trigeminal pain pathways. We explored temporal summation of this reflex by using a train of pulses, rather than a single pulse, and remote activation of diffuse noxious inhibitory control (DNIC), to improve reliability, flexibility and nociceptive specificity of this technique. The R2 component of the nociceptive blink reflex response (nR2) was assessed in 28 healthy volunteers using between 1 and 7 pulses per stimulus train (inter-pulse interval 5 ms). The effect of DNIC on single-, double-, and triple-pulse nR2 was investigated. Compared to single pulses, double and triple pulses increased the sensation of pain, reduced the tactile and pain thresholds, and facilitated the blink reflex responses (reduced onset latency, increased magnitude and persistence of nR2). The maximal reflex facilitation was achieved using a triple pulse. Higher pulse numbers had no additional facilitatory effect. Activation of the DNIC system using heterotopic pain suppressed the nR2 evoked by double and triple stimulation by 16 and 42%, respectively, but not the nR2 from a single pulse. Stimulation with double and triple pulses may be more suitable to study influences on nociceptive pathways than single pulses and may widen the methodological flexibility of the nociceptive blink reflex technique. This technique may be useful in studying the trigeminal nociceptive system with particular reference to primary headache disorders and their neuropharmacology.     

Generation of renal Epo-producing cell lines by conditional gene tagging reveals rapid HIF-2 driven Epo kinetics,cell autonomous feedback regulation,and a telocyte phenotype

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Konzeptionelle und rechtliche Varianten der Versorgung von Menschen mit Demenz zwischen ambulant und stationär

In Germany, there clearly appears to be a gap between care carried out at home and in in-patient settings (residential nursing care). Numerous innovative projects of alternatively structured care, like for instance shared flats or group care units for people with dementia are placed in between the traditional, either home-based or institutionalised care patterns. It seems imperatively necessary to overcome the rigid separation between the inpatient sector and care carried out at home. In this article, backgrounds, necessities and perspectives of projects placed in between the traditional structures are discussed.     

Secondary amine precursors to nitrosamines in human saliva, gastric juice, blood, urine and faeces.

It has been suggested that the endogenous nitrosation of aliphatic, cyclic and heterocyclic secondary amines in the urinary bladder of patients with chronic urinary bacterial infections and in the human stomach may provide an important additional source of exposure to carcinogenic volatile N-nitrosamines. The most commonly occurring nitrosatable secondary amines found in human saliva, gastric juice, blood, urine and faeces are dimethylamine (DMA), pyrrolidine (PYR) and piperidine (PIP). All of 40 analysed samples of gastric juice contained 0.87 +/- 0.89 (SEM) microgram/ml DMA, 39 contained 1.35 +/- 2.53 microgram/ml PIP, 36 contained 0.18 +/- 0.15 microgram/ml PYR and 14 contained 0.05 +/- 0.11 microgram/ml diethylamine. Nitrate (14.0 +/- 15.7 microgram/ml) was present in all samples and 11 of 40 samples contained 0.43 +/- 1.38 microgram/ml nitrite. Only one gastric juice sample with pH less than 4.5 contained nitrite (0.1 microgram/ml). In paraplegics, patients with bladder augmentations and two control groups without bacterial infections of the urinary bladder, a mean daily excretion of 40.5-49.7 mg/day DMA, 19.4-23.8 mg/day PYR and 26.1-31.7 mg/day PIP was found. In both patient groups suffering from chronic bacterial infection of the urinary bladder, the corresponding volatile N-nitrosamines were formed by endogenous nitrosation and excreted in urine.     

Konzeptionelle und rechtliche Varianten der Versorgung von Menschen mit Demenz zwischen ambulant und station?r

In Deutschland zeigen sich in der Versorgung von Menschen mit Demenz deutliche Schnittstellenprobleme zwischen ambulanter und stationärer Versorgung. Zahlreiche Projekte innovativer Versorgungsformen platzieren sich zwischen traditionellen ambulanten und stationären Regelungsmustern, etwa Wohngemeinschaften oder Wohngruppen für Menschen mit Demenz. Die Überwindung der starren Grenzen zwischen ambulanten und stationären Logiken in der Versorgung von Menschen mit Demenz erscheint als dringend erforderlich. In diesem Beitrag werden die Hintergründe, die Notwendigkeiten und die Perspektiven von Versorgungsformen zwischen ambulant und stationär erörtert.     

Effektivität einer multifaktoriellen Intervention zur Reduktion von körpernaher Fixierung bei demenzerkrankten Heimbewohnern

Zusammenfassung Gegenwärtig existieren lediglich Beobachtungsstudien und Expertenmeinungen, die den Umgang von bewegungseinschränkenden Maßnahmen begründen. Demgegenüber steht eine sehr unterschiedliche Praxis in der Langzeitpflege und den akutmedizinischen Institutionen. Etwa 3–5% der Heimbewohner werden durchschnittlich körpernah fixiert. Es existieren große regionale Unterschiede. Die Hüftfrakturrate beträgt bei Heimbewohnern etwa 50 pro 1000 Bewohnerjahre. Ungefähr 40–50% der Heimbewohner werden mit potenziell bewegungseinschränkenden Psychopharmaka behandelt. Zur Untersuchung der Effektivität einer Intervention zur Reduktion von bewegungseinschränkenden Maßnahmen (BEM) bei Heimbewohnern mit kognitiven Einschränkungen wurde eine cluster-randomisierte Studie geplant. Die Intervention umfasst die Verbesserung des Wissens im Umgang mit BEM und den Einsatz von technischen Hilfen zur Reduktion von sturzbedingten Verletzungen. Die Studienpopulation umfasst mindestens 200 Bewohner in 54 Pflegeeinrichtungen in drei Bundesländern. Es wird eine 50% Reduktion der Fixierungszahlen angestrebt. Das Studiendesign sieht eine Wartelisten-Kontroll-Intervention vor. Primäre Endpunkte sind die Zahl der fixierten Personen und die Zeiten (Stunden) der Anwendungen von BEM. Der Einsatz von Psychopharmaka, Stürze und Verletzungen sowie neufixierte Personen werden ebenfalls dokumentiert. Die Studie umfasst eine gemeinsame dreimonatige Dokumentationsphase und eine vierteljährige Intervention. Mit der Untersuchung wird angestrebt, ein in die Praxis umsetzbares und kontrollierbares Modell zu testen.     

A randomized trial of surgical antimicrobial prophylaxis with and without vancomycin in organ transplant patients

BACKGROUND: Gram-positive organisms, including vancomycin-resistant enterococci (VRE), have emerged as major pathogens on the organ transplant service at our institution. We hypothesized that our use of vancomycin as part of routine surgical prophylaxis increased the risk of VRE colonization and infection; conversely, there was concern that failure to use vancomycin prophylaxis would increase peri-operative morbidity due to gram-positive organisms. METHODS: Renal transplant recipients (n = 88) were randomized to receive either a) vancomycin/ceftriaxone or b) cefazolin; and pancreas transplants (n = 24) to receive either a) vancomycin/gentamicin or b) cefazolin/gentamicin. Stool samples or rectal swabs were obtained for culture for enterococci within 24 h of transplantation and weekly while hospitalized. RESULTS: Enterococci were isolated on stool culture from 38 (34%) of 102 patients at the time of transplantation; 4 (11%) of the isolates were VRE. The percentage of patients who subsequently acquired VRE was low (1-7% per wk) but remained constant during hospitalization. There was no association between new VRE detection and vancomycin use for either prophylactic or therapeutic purposes. Forty-four patients (39%) had a post-operative infection with 46% of these infections due to gram-positive organisms; rates were unaffected by prophylactic vancomycin use. Pancreas transplant patients who did not receive vancomycin prophylaxis had a significantly longer initial hospitalization (p = 0.03); however, differences were not statistically significant when total length of stay (LOS) within the first 90 d of transplantation was compared. CONCLUSIONS: Vancomycin surgical prophylaxis does not appear to have an effect on VRE colonization or infection, or on rates of infection with gram-positive bacteria. Elimination of vancomycin prophylaxis in renal transplant patients may be a reasonable part of an overall program to limit vancomycin usage, although as a single measure, its impact may be minimal. Vancomycin surgical prophylaxis may be of greater importance in pancreas transplants.     

Mean daily intake of volatile N-nitrosamines from foods and beverages in West Germany in 1989-1990.

The levels of volatile N-nitrosamines were determined in 38 alcoholic drinks and 215 food samples prepared for human consumption using standard culinary practices. The analyses used gas chromatography-thermal energy analysis. Detectable levels were found in 80 (31.5%) of the individual samples. The average daily intake of volatile N-nitrosamines in West Germany in 1989-1990 was found to be: 0.28 microgram N-nitrosodimethylamine (NDMA)/day, 0.011 microgram N-nitrosopyrrolidine (NPYR)/day and 0.015 microgram N-nitrosopiperidine (NPIP)/day for men, and 0.17 microgram NDMA/day, 0.011 microgram NPYR/day and 0.015 microgram/NPIP/day for women. For men, 31% of the daily NDMA exposure results from the consumption of beer.