Expression of neurotrophic factors in neonatal rats after peripheral inflammation.

Neonatal peripheral inflammatory insult might result in the alteration of neuronal development in the nociceptive circuit. During early postnatal period, neurotrophins play important roles in neural development and sensory nerve innervation in the central and peripheral nervous systems. In this study, we investigated mRNA expression for neurotrophic factors and their receptors in the dorsal root ganglia of rat pups during postnatal life after peripheral inflammation induced by injection of complete Freund's adjuvant (CFA) into hind paw on postnatal day 1. Our results showed that mRNA expression levels of alpha-calcitonin gene-related peptides, tropomyosin-related kinase-A (trkA), p75 neurotrophin receptor (p75(NTR)), and brain-derived neurotrophic factor (BDNF) elevated significantly after CFA treatment. Such an increase began 1 day after CFA treatment and lasted 2 to 3 days for trkA, p75(NTR), and BDNF. In contrast, there was no change in mRNA expression levels for neurotrophin-4/5, beta-nerve growth factor (beta-NGF), trkB, glial cell line-derived neurotrophin factor, and receptor protein tyrosine kinase protein. Our study demonstrated that neonatal peripheral inflammatory insult might result in molecular changes of neurotrophic factors, particularly in NGF receptors and BDNF, in the process of neuronal development and plasticity in primary afferents during early neonatal period. PERSPECTIVE: Neonatal peripheral inflammation model has been used for the exploration of neuropathic pain mechanism for years. This work provided further detailed information about possible neurotransmitters and peptides involved in this process. This might also lead to future clinical application.     

Insulin lispro: in-vivo potency determination by intravenous administration in conscious rabbits.

Insulin lispro is a monomeric analogue of human insulin, produced by genetic engineering, and has been reported to have a more rapid absorption following subcutaneous injection than insulin. Since it has been shown to have a similar hypoglycaemic action to insulin in clinical studies and comparable properties in radioimmunoassay, the feasibility of using a bioassay which was designed originally for insulin, to measure insulin lispro potency was evaluated in this investigation. A random-dose bioassay protocol, in which insulin lispro and two insulin standards were administered intravenously in a random sequence, was used and validated in nine conscious healthy rabbits. The decline in blood-glucose levels, following the intravenous injection of a dose of insulin or its lispro analogue, was monitored by a continuous glucose monitoring system. A glucose response curve was generated, from which various pharmacodynamic parameters were determined. Compared with the insulin standards, the potencies of insulin lispro determined from nadir, basal glucose normalized nadir, glycaemic reduction and ABGC (area of the blood-glucose response curve under baseline) were observed to have mean (95% confidence limits) values of 97.0 (69.5-124.6)%, 106.3 (72.4-140.2)%, 949 (51.8-138.0)% and 102.4 (76.3-128.5)%, respectively. In addition, the coefficients of variation for correspondent parameters were 36.9, 41.5, 59.1 and 33.2%, respectively. The results indicated that the hypoglycaemic potency calculated from the ABGC values was the most accurate (102.4%) with the least coefficient of variation (33.2%). In conclusion, the potency of insulin lispro can be determined accurately from the ABGC values measured by the random-dose bioassay used.     

C ASE R EPORT: Dramatic response to lamivudine therapy following corticosteroid priming in chronic hepatitis B

A 21 year-old male patient with chronic hepatitis B was treated with lamivudine 150 mg daily after withdrawal of a short course of oral prednisolone (30 mg daily for 3 weeks, 15 mg daily for 1 week). Serum hepatitis B virus (HBV)-DNA increased during prednisolone pretherapy and serum alanine aminotransferase (ALT) was increasing after withdrawal of prednisolone. Clearance of HBV-DNA with hepatitis B e antigen seroconversion and ALT normalization occurred within 2 months after starting lamivudine therapy. If this dramatic response to lamivudine therapy after corticosteroid priming is confirmed by further studies, the regimens used in this particular case might become a powerful therapeutic tool for chronic HBV infection.     

Curcumin enhances p-cresyl sulfate-induced cytotoxic effects on renal tubular cells

Indoxyl sulfate (IS) and p-cresyl sulfate (PCS), protein-bound uremic toxins, can induce oxidative stress and cause renal disease progression. However, the different cytotoxic effects on renal cells between IS and PCS are not stated. Due to uremic toxins are generally found in CKD patients, the mechanisms of uremic toxins-induced renal injury are required to study. Curcumin has anti-oxidant, anti-inflammatory and anti-apoptotic effects which may be potential used to protect against renal damage. In contrast, curcumin also exert cytotoxic effects on various cells. In addition, curcumin may reduce or enhance cytotoxicity combined with different chemicals treatments. However, whether curcumin may influence uremic toxins-induced renal injury is unclear. The goal of this study is to compare the different cytotoxic effects on renal cells between IS and PCS treatment, as well as the synergistic or antagonistic effects by combination treatments with curcumin and PCS. Our experimental result shows the PCS exerts a stronger antiproliferative effect on renal tubular cells than IS treatment. In addition, our study firstly demonstrates that curcumin enhances PCS-induced cell cytotoxicity through caspase-dependent apoptotic pathway and cell cycle alteration.     

Enhancement of hypothermic heart preservation with fructose 1, 6-diphosphate.

BACKGROUND: We hypothesized that the addition of fructose 1, 6-diphosphate (FDP) to a hypothermic heart preservation solution could improve metabolic recovery because it has several beneficial effects. MATERIALS AND METHODS: Twenty adult Sprague-Dawley rats were used to study hypothermic heart preservation. The hearts were removed under general anesthesia and preserved at 4 degrees C in Euro-Collins solution (30 ml/kg) for 8 h. In the study group (N = 10), FDP (5 mM) was added to the Euro-Collins solution. In the control group (N = 10), no FDP was added. Heart function was studied after preservation using a working heart model. The ability of various concentrations of fructose 1,6-phosphate to passively diffuse through an egg phosphatidylcholine multilamellar vesicle (MLV) membrane bilayer was examined. RESULTS: Cardiac output ranged from 17.0 +/- 1.9 to 24.9 +/- 1.6 ml/min in the study group vs 2.0 +/- 1.0-12.3 +/- 1.7 ml/min for controls, average aortic flow was 10. 8 +/- 1.4 ml/min in the study group vs -1.3 +/- 1.6 ml/min for controls, and maximum LV generated power was 22.8 +/- 1.7 J/min vs 10.1 +/- 1.6 J/min for controls. Coronary flow, left ventricular stroke volume and stroke work, and myocardial oxygen consumption were much higher in the study group than in the control group. Coronary vascular resistance was lower in the study group than in the control group. Electron microscopic study indicated that many myocytes displayed patches of swollen mitochondria in the control group, but was rarely observed in the study group. The addition of 50 mM FDP caused substantial changes in MLV permeability. No dose of sucrose buffers outside the vesicles resulted in a significant changes of MLV permeability. CONCLUSIONS: Our results indicate that the addition of FDP to Euro-Collins solution significantly improves hypothermic rat heart preservation, and FDP appeared to cross the membrane bilayer.     

Non‐radioactive southern hybridization for early diagnosis of α‐thalassemia with Southeast Asian‐type deletion in Taiwan

α‐Thalassemia has been estimated to account for over 60% of hydrops fetalis cases in Taiwan. The most common genotypic lesion found in α‐thalassemia‐1 cases in Taiwan is deletion of a large segment of the α‐globin gene cluster, termed the Southeast Asian‐type deletion (−^SEA/; further referred to as SEA‐type deletion). Seven chorionic villus samples (CVS) from pregnancies of couples both heterozygous for SEA‐type deletion were studied. Non‐radioactive Southern‐blot hybridization using the dig‐alkaline phosphatase detection system was developed to fulfill this purpose. The results were compared with corresponding polymerase chain reaction (PCR) data to elucidate the effectiveness of these two protocols in the diagnosis of the SEA‐type deletion. The data showed that of the seven CVS, three demonstrated a distinctive band pattern, indicating their homozygous status of SEA‐type deletion, whereas two showed heterozygous patterns, and the other two were free of the deletion. Homozygosity of the deletion was confirmed by Southern‐blot hybridization performed on DNA samples extracted from the abortus tissue. However, two of the three cases with SEA‐type deletion showed heterozygous PCR results. Maternal cell contamination could be responsible for the artifacts in the PCR results, but the influence due to the contamination is minimal in non‐radioactive Southern‐blot hybridization. We concluded that PCR is suitable for screening of carrier adults with SEA‐type deletion, and non‐radioactive Southern hybridization is ideal for early prenatal diagnosis of the SEA‐type deletion. Am. J. Med. Genet. 95:332–335, 2000. © 2000 Wiley‐Liss, Inc.