Dexamethasone as an adjuvant for peripheral nerve blockade: a randomised,triple-blinded crossover study in volunteers

Background

The efficacy of dexamethasone in extending the duration of local anaesthetic block is uncertain. In a randomised controlled triple blind crossover study in volunteers, we tested the hypothesis that neither i.v. nor perineurally administered dexamethasone prolongs the sensory block achieved with ropivacaine.

The Well-being Model: A New Drug Interaction Model for Positive and Negative Effects

Background: Drugs are routinely combined in anesthesia and pain management to obtain an enhancement of the desired effects. However, a parallel enhancement of the undesired effects might take place as well, resulting in a limited therapeutic usefulness. Therefore, when addressing the question of optimal drug combinations, side effects must be taken into account.

Methods: By extension of a previously published interaction model, the authors propose a method to study drug interactions considering also their side effects. A general outcome parameter identified as patient's well-being is defined by superposition of positive and negative effects. Well-being response surfaces are computed and analyzed for varying drugs pharmacodynamics and interaction types. In particular, the existence of multiple maxima and of optimal drug combinations is investigated for the combination of two drugs.

Results: Both drug pharmacodynamics and interaction type affect the well-being surface and the deriving optimal combinations. The effect of the interaction parameters can be explained in terms of synergy and antagonism and remains unchanged for varying pharmacodynamics. For all simulations performed for the combination of two drugs, the presence of more than one maximum was never observed.     

Low level of response to alcohol as associated with serotonin transporter genotype and high alcohol intake in adolescents.

BACKGROUND: A low level of response to alcohol has been associated with both the genetic constitution of the regulatory region (SLC6A4) of the human serotonin (5-hydroxytryptamine, 5-HT) transporter (5-HTT) and with future alcohol intake and an increased risk for alcoholism. To date, all studies of relevant polymorphisms have been carried out in populations in the United States. METHODS: Data were extracted from a subset (n = 243) of a cohort of children who have been observed since birth through evaluation of the family history of alcoholism and psychosocial risk influences. At age 16 years, the response to alcohol was assessed with the Self-Rating of the Effects of Alcohol (SRE) questionnaire, and the average amount of alcohol intake per month was assessed during the prior 6 months. Additional variables that were measured included the 5-HTT genotype, externalizing behavior, and sociodemographic variables, such as gender and age. RESULTS: The level of response to alcohol was significantly lower among carriers of two long alleles of the 5-HTT regulatory region compared with carriers of one or two short alleles (Mann-Whitney U = 5225.0, p = .005). In a multiple regression analysis, the level of response to alcohol and externalizing behavior but not psychosocial factors significantly predicted the average amount of alcohol intake per month. CONCLUSIONS: This study demonstrates that, independent of the assessed psychosocial variables, the 5-HTT genotype correlated with the level of response to alcohol and predicted alcohol intake among 16-year-old adolescents.     

A QUANTITATIVE THEORY OF THE PRECIPITIN REACTION : VII. THE EGG ALBUMIN-ANTIBODY REACTION IN ANTISERA FROM THE RABBIT AND HORSE

1. In two rabbits subjected to prolonged injections with crystalline egg albumin the antibodies in one showed progressive changes such as noted in an earlier paper; the antibodies in the other did not. 2. The significance of this behavior in the production of sera for therapeutic use is pointed out. 3. Quantitative studies are reported on the low grade or incomplete antibody present in the early stages of immunization of a horse with egg albumin. 4. Quantitative studies on the flocculating antibody from later bleedings from the horse are given, and the dissociation of the soluble pre-zone compounds by rabbit anti-egg albumin is studied. Rough velocity estimations are reported. 5. The bearing of the findings on the mechanism of precipitin and flocculation reactions and of the Danysz effect is discussed in terms of the union of multivalent antigen with multivalent antibody.     

Regional cerebral glucose transport in insulin-dependent diabetic patients studied using [11C]3-O-methyl-D-glucose and positron emission tomography

Regional cerebral [11C]3-O-methyl-D-glucose ([11C]MeG) uptake kinetics have been measured in five insulin-dependent diabetic patients and four normal controls using positron emission tomography (PET). Concomitant measurement of regional cerebral blood volume and CBF enabled corrections for the presence of intravascular [11C]MeG signal in cerebral regions of interest to be carried out, and regional cerebral [11C]MeG unidirectional extraction fractions to be computed. Four of the five diabetic subjects were studied with their fasting plasma glucose level clamped at a normoglycaemic level (4 mM), and four were studied at hyperglycaemic plasma glucose levels (mean 13 mM). The four diabetic subjects whose fasting plasma glucose levels were clamped at a normoglycaemic level of 4 mM had mean fasting whole-brain, cortical, and white matter [11C]MeG extraction fractions of 15, 15, and 16%, respectively, values similar to those found for the four normal controls (whole brain, 14%; cortex, 13%; white matter, 17%). Mean regional cerebral [11C]MeG extraction fractions were significantly reduced in diabetic subjects during hyperglycaemia whether their plasma insulin levels were undetectable or whether they were raised by continuous intravenous insulin infusion. Such a reduction in [11C]MeG extraction under hyperglycaemic conditions can be explained entirely in terms of increased competition between [11C]MeG and D-glucose for the passive facilitated transport carrier system for hexoses across the blood-brain barrier (BBB). It is concluded that the number and affinity of D-glucose carriers present in the BBB are within normal limits in treated insulin-dependent diabetic subjects. In addition, insulin appears to have no effect on the transport of D-glucose across the BBB.     

Therapy of hemorrhoidal disease]

Hemorrhoidal disease is one of the most frequent disorders in western countries. The aim of individual therapy is freedom from symptoms achieved by normalisation of anatomy and physiology. Treatment is orientated to the stage of disease: haemorrhoids 1 are treated conservatively. In addition to high-fibre diet, sclerotherapy is used. Haemorrhoids 2 prolapse during defecation and return spontaneously. First-line treatment is rubber band ligation. Haemorrhoids 3 that prolapse during defecation have to be digitally reduced, and the majority need surgery. For segmental disorders, haemorrhoidectomy according to Milligan-Morgan or Ferguson is recommended. In circular disease, Stapler hemorrhoidopexy is now the procedure of choice. Using a therapeutic regime according to the hemorrhoidal disease classification offers high healing rates and low rates of complications and recurrence.     

Cutaneous leishmaniasis: Clinical report of two cases and review of the recent literature

With 1–1.5 million cases reported every year cutaneous leishmaniasis represents an increasing health problem. The course of cutaneous leishmaniasis varies from a single self‐healing ulcer to a persistent ulcer or progressive mucosal disease with nasopharyngeal destruction. An enormous array of topical and systemic treatment modalities has been endorsed. The response to treatment depends on the species of parasite as well as the host's immunological and genetic status. Species‐specific treatment guidelines based on evidence from controlled studies are highly desirable. We present two cases of cutaneous leishmaniasis, one in a child and one during pregnancy, reviewing various diagnostic and therapeutic measures with special attention to problems in young and pregnant patients.