A multifunctional pipette for localized drug administration to brain slices

We have developed a superfusion method utilizing an open-volume microfluidic device for administration of pharmacologically active substances to selected areas in brain slices with high spatio-temporal resolution. The method consists of a hydrodynamically confined flow of the active chemical compound, which locally stimulates neurons in brain slices, applied in conjunction with electrophysiological recording techniques to analyze the response. The microfluidic device, which is a novel free-standing multifunctional pipette, allows diverse superfusion experiments, such as testing the effects of different concentrations of drugs or drug candidates on neurons in different cell layers with high positional accuracy, affecting only a small number of cells. We demonstrate herein the use of the method with electrophysiological recordings of pyramidal cells in hippocampal and prefrontal cortex brain slices from rats, determine the dependence of electric responses on the distance of the superfusion device from the recording site, document a multifold gain in solution exchange time as compared to whole slice perfusion, and show that the device is able to store and deliver up to four solutions in a series. Localized solution delivery by means of open-volume microfluidic technology also reduces reagent consumption and tissue culture expenses significantly, while allowing more data to be collected from a single tissue slice, thus reducing the number of laboratory animals to be sacrificed for a study.     

How to think about interprofessional competence: a metacognitive model

Different professions meet and work together in teams every day in health and social care. To identify and deliver the best quality of care for the patient, teamwork should be both professionally and interprofessionally competent. How can enhanced education prepare teamworkers to be both professionally and interprofessionally competent? To achieve interprofessional skills and design effective interprofessional curricula, there is a need for metacognitive frameworks focusing on the relationship between theories and the problem-solving process as well as the structure and content of professional competence. The aim of this article is to discuss the need for shared metacognitive structures/models as a tool for securing successful interprofessional learning and developing personal, professional and interprofessional competence to improve the quality of care. A metacognitive model for interprofessional education and practice is presented in this article. This model has been developed as a tool for analyzing professional competence on three levels: individual, team and organization. The model comprises seven basic components of professional competence and the way they are related and interact. Examples of how this metacognitive model can be used in the early, middle and late stages in interprofessional education are given.     

Gram-negative bacteria from patients seeking medical advice in Stockholm after the tsunami catastrophe

Microbiological cultures from 229 patients seeking medical advice in Stockholm after the tsunami catastrophe of December 2004 were analysed at the Clinical Microbiology Laboratory, Karolinska University Hospital, Stockholm, Sweden. Gram-negative bacilli were the most common findings from wound cultures. Common human pathogens such as Escherichia coli, Proteus species, Klebsiella spp., and Pseudomonas aeruginosa were isolated. More rare species of Gram-negative bacilli, e.g. Myroides odoratus, Sphingomonas paucimobilis and Bergeyella zoohelcum were also isolated. Resistance towards ordinary antibiotics was more extensive compared to our Swedish reference material for Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis and Acinetobacter spp., but not for Pseudomonas aeruginosa, probably reflecting that the resistant isolates were nosocomially acquired in Asia.     

Sex-related differences in the associations between hyperleptinemia, insulin resistance and dysfibrinolysis

The adipocyte-derived hormone leptin is associated with insulin resistance and reduced fibrinolytic status--or dysfibrinolysis--in humans. As leptin associates differentially to the development of cardiovascular disease and diabetes in men and women, we hypothesized that leptin and insulin sensitivity are related to dysfibrinolysis in a sex-dependent manner. Thirty-two men and 40 women were recruited from the Monitoring of trends and determinants in Cardiovascular disease (MONICA) population sample, representing the highest and lowest quartiles of fasting insulin levels. Lipids, fibrinolytic status [plasminogen activator inhibitor 1 (PAI-1) activity, tissue plasminogen activator (tPA) mass and activity, and tPA-PAI complex], leptin, testosterone and sex-hormone-binding globulin were measured. Insulin sensitivity was estimated using the euglycaemic clamp technique. Body composition was determined by bioimpedance. Determinants for circulating levels of fibrinolytic factors were explored in a multivariate linear regression analysis. Levels of fibrinolytic variables and estimated insulin sensitivity did not differ between men and women. Leptin was independently associated with reduced fibrinolytic status (high PAI-1 activity, low tPA activity, high tPA mass, and high tPA-PAI complex) in men (P < 0.001-0.002). In women, fat mass and/or insulin sensitivity were related to these factors (P < 0.001-0.03), and leptin only to reduced tPA activity (P = 0.002). Hyperleptinemia, dysfibrinolysis, insulin sensitivity and androgenicity associate differentially in men and women.     

Altering the biochemical state of individual cultured cells and organelles with ultramicroelectrodes

We describe an efficient technique for the selective chemical and biological manipulation of the contents of individual cells. This technique is based on the electric-field-induced permeabilization (electroporation) in biological membranes using a low-voltage pulse generator and microelectrodes. A spatially highly focused electric field allows introduction of polar cell-impermeant solutes such as fluorescent dyes, fluorogenic reagents, and DNA into single cells. The high spatial resolution of the technique allows for design of, for example, cellular network constructions in which cells in close contact with each other can be made to possess different biochemical, biophysical, and morphological properties. Fluorescein, and fluo-3 (a calcium-sensitive fluorophore), are electroporated into the soma of cultured single progenitor cells derived from adult rat hippocampus. Fluo-3 also is introduced into individual submicrometer diameter processes of thapsigargin-treated progenitor cells, and a plasmid vector cDNA construct (pRAY 1), expressing the green fluorescent protein, is electroporated into cultured single COS 7 cells. At high electric field strengths, observations of dye-transfer into organelles are proposed.     

Cerebral artery blood velocity in normal subjects during acute decreases in barometric pressure.

To investigate the effect of acute changes in barometric pressure on regional cerebral perfusion we studied the middle cerebral artery (MCA) blood velocity in five healthy male volunteers by means of a low-pressure chamber. The MCA blood velocity, arterial blood and respiratory gases were measured at the barometric pressures of 1, 0.8, 0.65, and 0.5 atmospheres. The observed blood velocity (Vo) showed no systematic changes. Decreases in barometric pressure induced hypoxia and hypocapnia. When normalizing the MCA blood velocity (Vn) to a standard P(CO2) (5.3 kPa), thereby correcting for the hypoxic induced hypocapnia, we obtained an inverse relationship between cerebral artery blood velocity and arterial blood oxygen content (CaO2). The oxygen supply to the brain, estimated as the product of Vo and CaO2, decreased with lowering of the barometric pressure. However, the product of Vn and CaO2 remained constant. This suggests the existence of a regulatory mechanism attempting to maintain a constant oxygen supply to the brain during acute changes in CaO2, if the hyperventilation induced decrease in PCO2 can be omitted. In the artificial situation of a low pressure chamber, our findings are quite similar to those obtained at sea level. This indicates that the underlying mechanisms of control of cerebral blood flow do not change during acute exposure to altitude.     

Increased serum CD8 soluble antigen level is associated with blood lymphocyte abnormalities and other established indicators of a poor prognosis in adult Hodgkin's disease.

Measurement of the soluble form of CD8 antigen (sCD8), a surface membrane component of suppressor/cytotoxic T cells, has yielded useful information relevant to prognosis in children with acute lymphoblastic leukaemia and Hodgkin's disease (HD). An ELISA technique was used to measure the amount of sCD8 in sera from 123 adults with untreated HD. Significantly higher mean sCD8 levels were found in patients with advanced disease (stage III-IV; P less than 0.001), B-symptoms (P less than 0.001), male sex (P less than 0.05) and increased spontaneous and decreased Concanavalin A induced blood lymphocyte DNA-synthesis (P less than 0.05). Actuarial survival of patients with high sCD8 levels was significantly worse than that of the remainder (P less than 0.05). However, the sCD8 level did not add prognostic information to that achieved by age, sex, lactate dehydrogenase (LDH) or clinical stage. A significant correlation between the sCD8 and LDH levels (r = 0.33; P less than 0.001) and inverse correlations between sCD8 levels and total blood CD4+ (r = -0.52; P less than 0.001) and CD3+ (r = -0.39; P less than 0.01) cell counts were found. Ten patients were also studied in complete remission, showing a significantly reduced sCD8 level in comparison to the pretreatment value (P less than 0.05). Increased sCD8 in HD may indicate enhanced suppressor T cell activity possibly compromising the host disease balance which could explain the association with prognosis.     

Every third patient in primary care suffers from depression,anxiety or alcohol problems

The aims of the study were to explore the prevalence of patients with depression and anxiety in primary care, its co-occurrence with hazardous/harmful alcohol use, and its relation to gender, age and reason for visit. A questionnaire, including the self-rating Hospital Anxiety and Depression scale and the Alcohol Use Disorder Identification Test, was consecutively distributed to 1800 patients at 11 primary healthcare centres in the county of Västerbotten, Sweden. The response rate was 77.3% (1392 patients), 38% men and 62% women. A total of 31.9% showed symptoms of depression and/or anxiety, with no gender differences. Harmful/hazardous alcohol use was found in 11.9% of the patients, 17.3% in men and 8.8% in women, although the region in Sweden has relatively low alcohol consumption among the population. Age was an important factor. Incidences of the conditions often occurred simultaneously. About half (51%) of those with harmful/hazardous alcohol use also showed symptoms of depression and/or anxiety. The most common causes for patients with symptoms of depression, anxiety or risk consumption of alcohol to seek care were the same as for the general population, namely complaints of pain or infection. Only 7.8% visited the primary care for psychiatric reasons, according to their own given reasons. In all, 38% of the patients showed signs of psychiatric symptoms and/or alcohol problems or a combination of these. The fact that every third patient showed symptoms of depression, anxiety and/or alcohol problems underlines the strategic position for early identification, intervention and treatment within primary healthcare.     

Transsexualism—General outcome and prognostic factors: A five-year follow-up study of nineteen transsexuals in the process of changing sex

Ninetten transsexuals, approved for sex reassignment, were followed-up after 5 years. Outcome was evaluated as changes in seven areas of social, psychological, and psychiatric functioning. At baseline the patients were evaluated according to axis I, II, V (DSM-III-R), SCID screen, SASB (Structural Analysis of Social Behavior), and DMT (Defense Mechanism Test). At follow-up all but 1 were treated with contrary sex hormones, 12 had completed sex reassignment surgery, and 3 females were waiting for phalloplasty. One male transsexual regretted the decision to change sex and had quit the process. Two transsexuals had still not had any surgery due to older age or ambivalence. Overall, 68% (n=13) had improved in at least two areas of functioning. In 3 cases (16%) outcome were judged as unsatisfactory and one of those regarded sex change as a failure. Another 3 patients were mainly unchanged after 5 years. Female transsexuals had a slightly better outcome, especially concerning establishing and maintaining partnerships and improvement in socioeconomic status compared to male transsexuals. Baseline factors associated with negative outcome (unchanged or worsened) were presence of a personality disorder and high number of fulfilled axis II criteria. SCID screen assessments had high prognostic power. Negative self-image, according to SASB, predicted a negative outcome, whereas DMT variables were not correlated to outcome. Supported by Swedish Medical Research Council Grant 3-21X-10411-01A, and a grant from the Joint Committee of Northern Health Regions.