Aerobic capacity in adults with tetralogy of Fallot

BACKGROUND: We investigated the aerobic capacity of 168 adult patients who had undergone successful surgical repair of retralogy of Fallot at the University of Toronto Congenital Cardiac Centre for Adults. METHODS: We compared values of peak uptake of oxygen, peak heart rate, forced vital capacity, and forced expiratory volume in 1 second to predicted values for their age groups. RESULTS: The patients who had undergone surgical repair of tetralogy of Fallot demonstrated an overall diminished peak uptake of oxygen, at 51%,and peak heart rate, at 79%, compared to predicted values. No difference in peak aerobic capacity was found according to the initial surgical strategy of palliation or repair. CONCLUSIONS: Adult patients who have undergone surgical repair of tetralogy of Fallot have lower peak uptake of oxygen, and peak heart rate, compared to predicted values. The reduction in the peak heart rate may affect their exercise capacity. The peak uptake of oxygen also decreased with increasing age at the time of testing, and the age at surgical repair.     

Normalized dyslipidaemia after parathyroidectomy in mild primary hyperparathyroidism: population-based study over five years

OBJECTIVE: Postmenopausal women are at increased risk of primary hyperparathyroidism (pHPT). Secondary dyslipidaemia in pHPT has attracted little attention, although morbidity and mortality associated with cardiovascular diseases have been reported to be increased in these patients. DESIGN: A population-based screening programme was used to recruit postmenopausal women with mild, asymptomatic pHPT (mean serum calcium 2.57 +/- 0.12 mmol/l) and matched controls. MEASUREMENTS AND PATIENTS: Serum lipids, lipoprotein fractions and influences of treatment for the parathyroid disease were studied in 87 case-control pairs (mean age 67 years), 69 of whom completed a 5-year follow-up period. RESULTS: pHPT was characterized by decreased serum high-density lipoprotein (HDL)-cholesterol, increased total triglycerides, very-low-density lipoprotein (VLDL)-triglycerides and VLDL-cholesterol levels and an elevated atherogenic index. The differences were more pronounced in the cases with serum parathyroid hormone levels in the normal range and were inversely correlated to the serum parathyroid hormone level. Parathyroidectomy, with or without additive hormone replacement therapy, normalized the dyslipidaemia. Five-year surveillance of pHPT without treatment was associated with a maintained increase in total triglycerides and the atherogenic index and a decrease in HDL-cholesterol levels. CONCLUSION: Proatherosclerotic dyslipidaemia characterizes mild pHPT and is effectively reversed by parathyroidectomy. As dyslipidaemia might contribute to the increased risk of cardiovascular diseases and death observed in pHPT, the findings favour operative intervention rather than conservative surveillance in mild, asymptomatic pHPT in postmenopausal females.     

Comparison of tension-band and figure-of-eight wiring techniques for treatment of olecranon fractures

Two different internal fixation techniques for closed displaced fractures of the olecranon were evaluated at a mean of 18 years after injury. Thirty-two of the patients received tension-band wiring, and 35 received figure-of-eight wiring. There were 41 women (mean age, 52 years) and 26 men (mean age, 32 years) included. The results revealed that 80% of the patients had no subjective complaints, 16% had occasional pain, and 4% had daily pain. Comparison of the injured and uninjured elbows demonstrated a 3 degrees reduction of flexion (P <.05) and a 5 degrees loss of extension (P <.01). More than 50% of the fractured elbows had degenerative changes (joint space narrowing, subchondral cysts, subchondral sclerosis, and osteophytes) (P <.001), and 4 had osteoarthritis (P <.05). No subjective, objective, or radiographic differences were found when the two techniques were compared. Removal of the hardware was performed in 81% of the patients with tension-band wiring and in 43% of the patients with figure-of-eight wiring (P <.01). The figure-of-eight technique can, therefore, be recommended, as it is associated with less frequent secondary procedures for hardware removal.     

Contribution of solid-state properties to the aqueous solubility of drugs.

This study investigates the influence of the solid-state properties melting point (T(m)), enthalpy of melting (DeltaH(m)) and entropy of melting (DeltaS(m)) of a drug on its intrinsic solubility (S(0)). For this purpose, 26 chemically and structurally diverse drugs covering the oral drug space were selected and the S(0), T(m), DeltaH(m) and DeltaS(m) were determined experimentally. The influence of T(m), DeltaH(m) and DeltaS(m) on S(0) was studied using regression analysis. The overall improvement of the predictions were 0.3 log units, however, five compounds (astemizole, glyburide, fenbufen, gliclazide and griseofulvin) were improved by more than one log unit. T(m) and DeltaH(m) had a larger effect than DeltaS(m) on the solubility predictions. The well-known general solubility equation (GSE) and the Dannenfelser semi-empirical equation for the calculation of DeltaS(m) were evaluated using our data set. While predictions of drug solubility obtained using the GSE were acceptable, the use of the experimental DeltaS(m) values instead of the constant 56.5 J mol(-1)K(-1) improved the accuracy of the prediction. The Dannenfelser equation underestimated the DeltaS(m) for most compounds with on average 15 J mol(-1)K(-1). Our results show that solid-state properties should be considered for improved performance of future models for prediction of drug solubility. In addition our study provides accurate experimental data on intrinsic solubility for 26 compounds, supplying a useful external data set for validation of drug solubility models.     

VEGF and VEGF receptor-1 concentration in vestibular schwannoma homogenates correlates to tumor growth rate.

OBJECTIVE: Vascular endothelial growth factor (VEGF) is one of the most potent mediators of angiogenesis, which is a mandatory process during tumor growth. Immunohistochemical studies have demonstrated VEGF expression in vestibular schwannomas (VS), and a semi-quantitation of staining intensity indicated a correlation between tumor growth rate and VEGF expression. The present objectives were to determine the concentration of VEGF and the high-affinity receptor VEGFR-1 in VS homogenates and to examine a possible correlation with symptom duration, tumor size, or growth rate. STUDY DESIGN, PATIENTS, AND METHODS: Prospective selection of 27 patients with VS growth determined by repeated magnetic resonance imaging. Patient files were reviewed for symptom duration and all magnetic resonance images reviewed for determination of tumor size and growth rate. ELISA was used for determination of the VEGF and VEGFR-1 concentration in tumor homogenates. SETTING: Tertiary University Hospital Clinic. RESULTS: All tumor homogenates contained VEGF and VEGFR-1. A significant correlation existed between the concentration of both VEGF and VEGFR-1 and tumor growth rate but not symptom duration or tumor size. CONCLUSION: The concentration of VEGF and VEGFR-1 in VS homogenates correlates with tumor growth rate but not with tumor size or symptom duration. We conclude that VEGF and VEGFR-1 appear to be directly involved in the growth pattern of VS.     

Ethnic differences in the time trend of female breast cancer incidence: Singapore, 1968 – 2002

Background  

From 1968 to 2002, Singapore experienced an almost three-fold increase in breast cancer incidence. This increase appeared to be different across the three main ethnic groups: Chinese, Malays and Indians. This paper used age-period-cohort (APC) modelling, to determine the effects of age at diagnosis, calendar period, and birth cohort on breast cancer incidence for each ethnic group.