A dissolution rate apparatus for the prediction of initial drug absorption patterns in beagles: Tolbutamide tablets

An apparatus utilizing liquid turbulence to simulate hydrodynamic conditions generated by gastrointestinal peristalsis was designed to estimate drug release from solid oral dosage forms. This turbulence was achieved through special arrangement of a pipetting pump to a dissolution chamber. By adjusting the flow rate of the pump to deliver and withdraw a fixed volume of dissolution medium per minute, a correlation was developed between dissolution rates and absorption patterns in beagles of two commercial tolbutamide tablets, A and B, and a micronized tolbutamide suspension. On the basis of this relationship, it was possible to predict the initial absorption patterns of two misformulated tablets, C and D.     

Acute renal failure in patients with ischemic heart disease: causes and novel approaches in breaking the cycle of self-perpetuating insults abrogated by surgery

At present, there seems to be diametrically opposing views on the causes of acute renal insufficiency in patients with ischemic heart disease (IHD) elective for cardiac revascularization. In this review, we examined recent advances in the understanding of the pathophysiology of acute renal failure in patients with IHD and surgery-induced acute phase reaction. Emphasis is given to the cellular and molecular mechanisms that contribute to the initiation and progression of inflammation. We evaluated the different pharmacological, technical, and surgical strategies used to improve the outcome of patients with IHD with impaired renal dysfunction and analyzed the influence of renal insufficiency on long-term results after surgery.     

Lymphangiography in Tuberculous Lymphadenitis

A rare lymphangiographic feature of tuberculous lymphadenitis in a patient who was investigated for generalised lymphadenopathy is presented.     

Urinary citrate in preterm and term babies

OBJECTIVES: (1) To determine a normal range for urinary citrate for term babies. (2) To compare urinary citrate measured in ex preterm babies at term with this normal range. (3) To evaluate whether urinary citrate was related to presence of nephrocalcinosis (NC) and chronic Lung Disease (CLD) in these ex preterm babies. STUDY DESIGN: Urinary citrate was measured in 38 healthy term babies (mean birth weight 3.52 kg, mean gestation 41 weeks) at a mean postnatal age of 3 days (1-5 days) and in 53 ex preterm babies (<32 weeks gestation at birth) at term. These preterm babies were part of a larger study on NC in which two renal ultrasound scans were performed at 1 month and term. RESULTS: The normal range for urinary citrate in term babies was 0.025-2.97 (mean 1.03) mmol/l and citrate/creatinine ratio 0.0011-0.852 (mean 0.27). In the ex-preterm urinary citrate was not significantly different (mean 1.1 vs. 1.03, p=0.7232) but urine citrate/creatinine ratio was significantly higher (mean 1.27 vs. 0.27, p=0.0005). There was no significant difference in urinary citrate or ratios of citrate/creatinine and calcium/citrate in the 11 (20.7%) with NC or in the 17 (32%) babies with CLD. There was no significant relationship found between duration of TPN and urinary citrate measured at term. CONCLUSION: We have determined a normal range for urinary citrate in healthy term babies in the first week of life. The range was very wide. Ex preterm babies had similar values at term and there was no association between urinary citrate and NC or CLD.     

HIV dynamics with multiple infections of target cells

The high incidence of multiple infections of cells by HIV sets the stage for rapid HIV evolution by means of recombination. Yet how HIV dynamics proceeds with multiple infections remains poorly understood. Here, we present a mathematical model that describes the dynamics of viral, target cell, and multiply infected cell subpopulations during HIV infection. Model calculations reproduce several experimental observations and provide key insights into the influence of multiple infections on HIV dynamics. We find that the experimentally observed scaling law, that the number of cells coinfected with two distinctly labeled viruses is proportional to the square of the total number of infected cells, can be generalized so that the number of triply infected cells is proportional to the cube of the number of infected cells, etc. Despite the expectation from Poisson statistics, we find that this scaling relationship only holds under certain conditions, which we predict. We also find that multiple infections do not influence viral dynamics when the rate of viral production from infected cells is independent of the number of times the cells are infected, a regime expected when viral production is limited by cellular rather than viral factors. This result may explain why extant models, which ignore multiple infections, successfully describe viral dynamics in HIV patients. Inhibiting CD4 down-modulation increases the average number of infections per cell. Consequently, altering CD4 down-modulation may allow for an experimental determination of whether viral or cellular factors limit viral production.     

Melioidosis imported into Nepal

This is a report of the first recognized case of melioidosis in Nepal. Illness began 1 month after returning from Malaysia after a 1 y stay. The case highlights the importance of ascertaining the travel history in any patient with a suspected infectious disease in this age of global travel.