Penetration and distribution of three lipophilic probes in vitro in human skin focusing on the hair follicle.

Fluorescent model substances of increasing lipophilicity (Oregon Green) 488, Bodipy, FL C5 and Bodipy 564/570 C5) were selected to enable the visualization in the skin using confocal laser scanning microscopy. After measuring the penetration for 18 h, the nonfixed human scalp skin was imaged from the bottom parallel to the stratum corneum and in a cross-section view perpendicular to the skin surface. The images were evaluated by calculating relative accumulation values for different penetrants. The studies indicate that the penetrated amount is highest for Bodipy FL C5 (medium lipophilicity) and lowest for Bodipy 564/570 C5 (high lipophilicity) whereas Bodipy 564/570 C5 (high lipophilicity) reveals the highest relative accumulation in parts of the hair follicle compared to Oregon Green 488 (low lipophilicity). The addition of 30% (v/v) ethanol to the donor phase of substance with a low lipophilicity increases the follicular delivery. From our results we conclude that delivery to the hair follicle can be improved by increasing the drugs lipophilicity and optimizing the composition of the donor phase. However, no conclusion can be drawn about the actual route of transport to the hair follicle.     

Acute and chronic whiplash disorders--a review.

OBJECTIVE: This review examines acute and chronic whiplash-associated disorders to facilitate assessment, treatment and rehabilitation for further research and evidence-based practices. DESIGN: A review of the literature. RESULTS AND CONCLUSION: Whiplash-associated disorders account for a large proportion of the overall impairment and disability caused by traffic injuries. Rarely can a definite injury be determined in the acute (or chronic) phase. Crash-related factors have been identified, and several trauma mechanisms possibly causing different injuries have been described. Most whiplash trauma will not cause injury, and the majority of patients (92-95%) will return to work. Litigation is not a major factor. Cognitive impairments are not the same as brain injury. Variables such as pain intensity, restricted motion, neurological symptoms and signs, together with central nervous system symptoms can be used to predict a situation with risk of remaining complaints. Influences of other factors--the same as for other chronic pain conditions--also exist. Persistent/chronic pain is not merely acute pain that persists over time; changes occur at different levels of the pain transmission system. Chronic whiplash-associated disorders are associated with problems concerning social functioning, daily anxieties and satisfaction with different aspects of life. Adequate information, advice and pain medication together with active interventions might be more effective in the acute stage. Early multidisciplinary rehabilitation focusing on cognitive-behavioural changes might be of value. To develop specific treatment and rehabilitation, it is important to identify homogenous subgroups.     

Retrosternal epiphyseal disruption of medial clavicle: case and review in children

Retrosternal dislocations of the clavicle have been reported previously in adults throughout the orthopedic literature. However, in children few cases have been noted in either the pediatric, emergency, or orthopedic literature. The potential for great vessel injury as well as acute airway compromise makes the retrosternal disruption of the sternoclavicular joint a surgical emergency that must be diagnosed quickly. Diagnosis is enhanced by the cephalic tilt view and by computed tomography (CT scan), as planar x-ray and tomography do not always reveal this potentially life-threatening condition. Surgical consultation must be sought acutely; however, management may need to begin prior to definitive repair. Emergency management begins by suspecting the injury, and with immediate airway and circulatory support for the patient.     

Inversion of the Bohr effect upon oxygen binding to 24-meric tarantula hemocyanin.

The Bohr effect describes the usually negative coupling between the binding of oxygen and the binding of protons to respiratory proteins. It was first described for hemoglobin and provides for an optimal oxygen supply of the organism under changing physiological conditions. Our measurements of both oxygen and proton binding to the 24-meric tarantula hemocyanin establish the unusual case where a respiratory protein binds protons at low degrees of oxygenation but releases protons at high degrees of oxygenation. In contrast to what is observed with hemoglobin and other respiratory proteins, this phenomenon amounts to the inversion of the Bohr effect in the course of an oxygen-binding curve at a given pH value. Therefore, protons in spider blood can act either as allosteric activators or as allosteric inhibitors of oxygen binding, depending on the degree of oxygenation of hemocyanin. These functional properties of tarantula hemocyanin, which cannot be explained by classical allosteric models, require at least four different conformational states of the subunits. Inspection of the known x-ray structures of closely related hemocyanins suggests that salt bridges between completely conserved histidine and glutamate residues located at particular intersubunit interfaces are responsible for the observed phenomena.     

Smooth muscle antibodies in Mycoplasma pneumoniae infection.

Paired sera from forty-five cases of Mycoplasma pneumoniae (MP) infection associated with acute lower respiratory tract illness were examined by immunofluorescence for antibodies to smooth muscle. Twenty-five (56%) of these cases had smooth muscle antibodies (SMA) of IgM class. A significant (greater than or equal to 4-fold) increase in titre of these antibodies was demonstrated in fifteen of thirty-five patients with a significant rise in titre of MP antibodies. SMA of IgG class occurred in eleven of forty-five cases (24%), but a 4-fold rise in antibody titre was found only in two cases. Three of forty-five sera (7%) from healthy donors contained SMA of IgM class and eight sera (18%) SMA of IgG class. MP antigen did not absorb SMA. Liver tests were performed in twenty-nine patients. In eighteen patients SGPT values were moderately or slightly elevated. There was no correlation between the occurrence of increased levels of transaminases and the presence of SMA in serum. In a patient with active chronic hepatitis, who had had a high titre of SMA exclusively of IgG class for 2 years, SMA of IgM class appeared transiently in association with an acute respiratory illness due to MP.     

Residual cholesterol synthesis and simvastatin induction of cholesterol synthesis in Smith-Lemli-Opitz syndrome fibroblasts

Smith-Lemli-Opitz syndrome (RSH/SLOS) is an autosomal recessive, malformation syndrome caused by mutations in the 3beta-hydroxysterol delta7-reductase gene (DHCR7). DHCR7 catalyzes the reduction of 7-dehydrocholesterol (7DHC) to cholesterol. We report the mutation analysis and determination of residual cholesterol synthesis in 47 SLOS patients, and the effects of treatment of SLOS skin fibroblasts with simvastatin. Using deuterium labeling we have quantified the amount of synthesized cholesterol and 7DHC in homozygote, heterozygote, and control fibroblast cell lines. In SLOS fibroblasts, the fraction of synthesized cholesterol to total sterol synthesis ranged from undetectable to over 50%. This establishes that different mutant alleles encode enzymes with varying degrees of residual activity. There was a correlation between increased phenotypic severity and decreased residual cholesterol synthesis (r(2)=0.45, p<0.0001). Simvastatin treatment of SLOS fibroblasts with residual DHCR7 enzymatic activity decreased 7DHC levels and increased cholesterol synthesis. This increase in cholesterol synthesis is due to increased expression of a mutant allele with residual function. Determination of residual enzymatic activity for specific DHCR7 mutant alleles will help in understanding the processes underlying the broad phenotypic spectrum found in this disorder and will be useful in identifying patients who may benefit from simvastatin therapy.     

Physiological and Psychological Effects of Delivering Medical News Using a Simulated Physician–Patient Scenario

We examined the acute stress response associated with having to deliver either bad or good medical news using a simulated physician–patient scenario. Twenty-five healthy medical students were randomly assigned to a bad medical news (BN), a good medical news (GN), or a control group that read magazines during the session. Self-report measures were obtained before and after the task. Blood pressure and heart rate were measured throughout the task period. Four blood samples were obtained across the task period. The BN and GN tasks produced significant increases in self-reported distress and cardiovascular responses compared with the control group. There was also a significant increase in natural killer cell function 10 min into the task in the BN group compared with the control group. The BN task was also somewhat more stressful than the GN task, as shown by the self-report and cardiovascular data. These findings suggest that a simulated physician–patient scenario produces an acute stress response in the physician, with the delivery of bad medical news more stressful than the delivery of good medical news.     

Catechol-O-methyltransferase activity in erythrocytes in Down''s syndrome: family studies

Catechol-O-methyltransferase (COMT) activity in erythrocytes was measured in six children with Down's syndrome and in their parents to determine if COMT activity is related to a gene on chromosome 21. A gene dosage effect was a possible explanation of the COMT value in three of the children but not in the other three.