A planar slab bidomain model for cardiac tissue

A fully three-dimensional model of the ventricular or atrial free wall will involve a planar geometry of finite thickness. The governing equations for the interstitial and extracellular potential of a planar slab of cardiac tissue comprised of parallel fibers undergoing uniform plane-wave activation are presented. A comparison with a bidomain of cylindrical geometry with the same half-thickness shows that the potentials in the planar bidomain (as a function of depth) approach core-conductor behavior more quickly.     

DNA immunization efficiently targets conserved functional domains of protease and ATPase/helicase of nonstructural 3 protein (NS3) of human hepatitis C virus

Nonstructural protein 3 (NS3) of human hepatitis C virus (HCV) is a conserved multi-functional protein essential for replication and translation of viral RNA and polyprotein processing. Early T-cell response against NS3 is capable of restricting viremia. We aimed at characterizing the immunogenicity in gene immunization of the conserved regions of NS3 critical for protein folding and activity. C57BL/6 mice were injected with NS3 gene of Russian HCV 1b isolate 274933RU. Immunization did not exert any overt histological changes and had no long-term effects on the immune status of NS3 gene-recipients. The immune response in NS3 gene-recipients was screened by antibody ELISA, T-cell proliferation test and immune assays for specific cytokine production. T-lymphocytes of NS3 gene-recipients proliferated in response to peptides representing conserved regions of protease and ATPase/helicase. Stimulated T-lymphocytes produced IL-2, and in response to protease-derived peptides, also IFN-gamma. Potent and long-lasting antibody response was raised against conserved NS3 regions including "Greek-key" motif of protease, motifs II, V and polynucleotide-binding domains of ATPase/helicase. Thus, gene immunization effectively targeted conserved regions critical for NS3 protease and helicase function. In type and specificity, immune response of NS3 gene-immunized mice mimicked immunity achieved in the acute self-limiting HCV infection of human and primates and in virus-exposed healthy individuals, indicating promiscuity of NS3 as immunogen.     

Predictors of health-related quality of life in Parkinson’s disease: the impact of overlap between health-related quality of life and clinical measures

Quality of Life Research - This study aimed to determine predictors of health-related quality of life (HRQoL) in Parkinson's disease (PD) and to explore their predictive value before and after...     

A prospective study of the effect of testosterone escape on preradiotherapy prostate-specific antigen kinetics in prostate cancer patients undergoing neoadjuvant androgen deprivation therapy

Introduction:Prostate-specific antigen (PSA) kinetic patterns during neoadjuvant androgen deprivation therapy have been shown to predict unfavorable long-term outcomes.Objective:To investigate the effect of testosterone escape (TE) on these kinetic patterns, as this had not been previously reported.Methods:There were 50 consecutive prostate cancer patients who received 6 months of triptorelin prior to definitive radiotherapy (RT). Testosterone and PSA levels were measured at baseline and every 6 weeks. Clinical factors were tested for their ability to predict for TE and unfavorable PSA kinetic patterns. The effects of TE, at both 1.7 and 0.7 nmol/L levels, were analyzed.Results:TE occurred in at least one reading for 14% and 34% of the patients at the 1.7 and 0.7 nmol/L levels, respectively. No baseline factors predicted TE. The median PSA halving time was 25 days and the median pre-RT PSA level was 0.55 ng/mL. The only factor significantly associated with a higher pre-RT PSA level was a higher baseline PSA level. The only factor that significantly predicted a longer PSA halving time was TE at the 1.7 nmol/L level.Conclusions:TE and higher baseline PSA levels may adversely affect PSA kinetics and other outcomes for patients undergoing neoadjuvant hormone therapy prior to radiotherapy. Studies investigating the tailoring of neoadjuvant therapy by extending the duration in those patients with a higher baseline PSA level or by the addition of anti-androgens in those demonstrating TE, should be considered.     

Traumatic rupture of the thoracic aorta: Should one always operate immediately?

Although the traditional therapy for blunt traumatic rupture of the thoracic aorta (TRA) is immediate operative repair, there may be a selective role for delayed repair, particularly in patients with head trauma, respiratory failure, or cardiac dysfunction. The present study examines the hypothesis that TRA can be managed by selective delayed operative repair. Clinical data were collected from 59 consecutive patients with TRA at a regional trauma unit. All TRAs were at the aortic isthmus. Patients were retrospectively classified into three groups: group I (n=12) included patients who either arrived in extremis or rapidly became unstable during triage; group II (n=3) included patients who had no contraindications to early repair and underwent repair at the time of diagnosis; and group III (n=44) consisted of patients who because of concomitant injuries or sepsis required initial admission and management in the intensive care unit until their clinical status had improved sufficiently to allow for deliberate delayed operative repair of the TRA. The delay ranged from 1 day to 7 months. Eight patients have yet to undergo repair and remain well at follow-up from 1 to 4 years. Overall survival rates in groups I, II, and III were 17%, 100%, and 82%, respectively. The surgery-related mortality rate in group III was 10% (three patients). Only two (4.5%) patients in group III died as a result of a ruptured aorta within 72 hours of admission. In conclusion, contrary to surgical doctrine, TRA may not require immediate operative repair in all cases, but may instead be managed selectively depending on the patient's clinical status.     

Exostoses of the external auditory canal: a long‐term follow‐up study of surgical treatment

To determine the postoperative incidence, extent and recurrence rate of exostoses of the external auditory canal in a cohort of patients involved in different water sports. A cross‐sectional study of 31 patients (46 ears), with exostoses treated by surgery in the Royal Cornwall Hospital between 1980 and 1999. A questionnaire was used to obtain information about the type of water exposure pre‐ and postoperatively. The extent of recurrent stenosis was assessed. The mean postoperative time interval was 10 years (sd = 4.5 years). The degree of stenosis was assessed as: minimal (<30%) in 42.6%, moderate (30–60%) in 31% and severe (>60%) in 25% of ears. The Cox regression model was used to identify factors associated with a reduction in the recurrence rate of stenosis. The use of ear plugs was highly significant (P = 0.015), as was the age of the patient at the time of operation (P = 0.004), i.e. the older the patient, the faster recurrent disease developed. There was no evidence to show that either the type or seasonal pattern of water sport activity influenced recurrence of the disease postoperatively, although preoperatively, the stenosis was more marked in association with surfing and sailing. Exostoses developed faster preoperatively in those who were in the water all year round rather than just the summer months. Of five patients who stopped water sport activity completely after surgery, four of them developed significant recurrent exostoses (>50% stenosis).     

Hydration status,body composition,and anxiety status in aeronautical military personnel from Spain: a cross-sectional study

Background: An adequate hydration status is critical to ensure efficiency during mental and physical activities.Our goal was to assess the hydration status of a Spanish group of aeronautical military men and to determine the association of hydration status with body composition and anxiety.Methods: A total of 188 men were evaluated through a validated hydration questionnaire, anthropometric and biochemical parameters, and an anxiety questionnaire. Based on these methods, the criteria of hydratio...