Time-dependent Effects of Klebsiella pneumoniae Endotoxin on Hepatic Drug-metabolizing Enzyme Activity in Rats

The time-dependent effects of Klebsiella pneumoniae endotoxin on hepatic cytochrome P450-dependent drug-metabolizing capacity (cytochrome P450 and b₅ content, activity of aminopyrine N-demethylase, p-nitroanisole O-demethylase, aniline hydroxylase and benzphetamine N-demethylase) and on the pharmacokinetics of antipyrine have been determined in rats. Measurement of enzyme activity and antipyrine (after intravenous injection of 20 mgkg^?1) were performed 2, 24 and 96 h after a single intraperitoneal injection of endotoxin (1 mgkg^?1) and after repeated doses (once daily for 4 days). The contribution of tumour necrosis factor α (TNFα) to the endotoxin-induced changes was also examined in rats pretreated with granulocyte colony-stimulating factor (G-CSF). The systemic clearance of antipyrine and the activity of hepatic cytochrome P450-dependent drug-metabolizing enzymes were dramatically reduced 24 h after a single injection of endotoxin, but had returned to control levels by 96 h. The magnitudes of these decreases in these measurements after repeated doses of endotoxin were similar to those seen 24 h after the single dose. The systemic clearance of antipyrine correlated significantly with cytochrome P450 content and aminopyrine N-demethylase activity. In histopathological experiments, moderate hypertrophy of Kupffer cells was observed, with no evidence of severe liver-tissue damage. G-CSF pretreatment suppressed the increased plasma concentrations of TNFα produced 2 h after single endotoxin injection, but did not eliminate the endotoxin-induced decrease in the systemic clearance of antipyrine, suggesting that TNFα is not the sole component responsible for the reduction of cytochrome P450-mediated drug-metabolizing enzyme activity. These results provide evidence that a single intraperitoneal injection of 1·0 mgkg^?1 K. pneumoniae endotoxin in rats reduces hepatic P450 and b₅ levels, and reduces the activity of various cytochrome P450-mediated drug-metabolizing enzymes without causing severe liver-tissue damage. This suggests that the effect of endotoxin on hepatic cytochrome P450-mediated drug-metabolizing isozymes is non-selective.     

Liver transplantation in a case of hypoproteinemia and coagulopathy

A female infant with hypoproteinemia and coagulopathy associated with hypertyrosinemia was successfully treated with living-related liver transplantation (LRLT). On the 12th day of life plasma amino acid analysis revealed a marked elevation of tyrosine, so the patient was fed on a low-tyrosine and low-phenylalanine diet. However, hepatosplenomegaly. hypotonia, alopecia, eczema and psychomotor delay did not improve and recurrent episodes of disseminated intravascular coagulation (DIC) caused her condition to deteriorate. Liver biopsy on the 230th day revealed marked fatty change accompanied by mild to moderate cholestasis. Therefore. LRLT from her father was performed on the 286th day resulting in improvement of all the aforementioned signs and symptoms. Despite a thorough examination, no diagnosis of a known disorder could be established. However, her elder brother had also been born with severe hypoproteinemia and coagulopathy, and died of DIC on the second day of life. Thus, the disorder is designated as a new entity, namely ‘congenital hypoproteinemia and coagulopathy associated with hypertyrosinemia’.     

Atrial Electrograms and Activation Sequences in the Transition Between Atrial Fibrillation and Atrial Flutter

Transition Between Atrial Fibrillation and Flutter. Introduction: The eletrophysiologic mechanism of atrial fibrillation (AF) has a wide spectrum, and it seems that some atrial regions are essential for the occurrence of a particular type of AF. We focused on one type of AF: AF associated with typical atrial flutter (AFI), which was right atrial (RA) arrhythmia, and sought to investigate intra-atrial electrograms and activation sequences in the transition between AF and AFL.
Methods and Results: Intra-atrial electrograms and activation sequences in the R.A free wall and the septum were evaluated in the transition between AF and AFL in seven patients without organic heart disease (all men; mean age 57 ± 11 years). In five episodes of the conversion of AFL into AF, the AFL cycle length was shortened (from 211 ± 6 msec in stable AFL to 190 ± 15 msec before the conversion, P, 0.001). Interruption of the AFL wavefront and an abrupt activation sequential change induced by a premature atrial impulse resulted in fractionation and disorganization of the septal electrograms. During sustained AF, septal electrograms were persistently fractionated with disorganized activation sequences. However, the RA free-wall electrograms were organized, and the activation sequence was predominantly craniocaudal rather than caudocranial throughout AF. In 12 episodes of the conversion of AF into AFL, the AF cycle length measured in the RA free wall increased (from 165 ± 26 msec at the onset of AF to 180 ± 24 msec before the conversion, P, 0.001). AFL resumed when fractionated septal electrograms were separated and organized to the caudocranial direction, despite the RA free-wall electrograms remaining discrete and sharp with an isoelectric line.
Conclusion: Changes of the electrogram and activation sequence in the atrial septum played an important role in the transition between AF and AFL.     

Clinical Trial with Authentic Recombinant Somatropin in Japan

Recombinant somatropin, produced by recombinant DNA technology, was administered by injection in daily doses of 8 IU to six healthy young volunteers. Daily injection for 4 days did not cause any significant change in the results of physical examination, blood count or urinalysis. Non-esterified fatty acid levels increased significantly from 0.45 ± 0.16 to 1.08 ± 0.12 mEq/litre (mean SEM) at 4 hours after the first injection (p<0.001). Plasma IGF-1 levels increased from 0.80 ± 0.14 units/ml to 1.72 ± 0.50, 3.22 ± 1.02, 3.17 ± 1.20 and 3.63 ± 0.78 units/ml at 24 hours after each daily injection for 4 days (p<0.001). Plasma hGH reached peak levels at 3 hours after intramuscular injection of recombinant somatropin, 4 IU, and this peak value was 57.3 ± 2.8 ng/ml. A total of 21 patients with pituitary dwarfism were also treated with recombinant somatropin for 6 months at a dose of 0.5 IU/kg/week. Their heights increased by 2.2–5.0 cm during the 6 months of treatment, which was calculated to be equivalent to 4.4–10.0 cm/year with a mean growth rate of 7.4 ± 0.4 cm/year. Anti-hGH antibody with a titre of 10 was observed in two patients at the end of 6 months of treatment.     

Prognosis and pathological characteristics of five children with non-Shiga toxin-mediated hemolytic uremic syndrome

BACKGROUND: The three major signs of hemolytic uremic syndrome (HUS) are hemolytic anemia, thrombopenia and acute renal failure. HUS is classified into Shiga toxin-mediated HUS (Stx-HUS) and non-Shiga toxin-mediated HUS (nStx-HUS). The prognosis of nStx-HUS is reported to be less favorable than that of Stx-HUS. Although the association between the prognosis and pathological characteristics of HUS have been reported such that the prognosis was considered to be poor for thrombotic microangiopathy (TMA) with predominant arterial involvement (arterial TMA), good for TMA with predominant glomerular involvement (glomerular TMA) and dependent on the extent of necrosis in cases of renal cortical necrosis, it is not yet clear whether pathological findings are also related to the renal prognosis of nStx-HUS cases. Therefore the purpose of the present paper was to analyze renal biopsy findings and prognosis for five children with nStx-HUS. METHODS: Clinical records of five cases of nStx-HUS among 74 cases of diagnosed HUS were reviewed, and information and data were summarized. RESULTS: Histological examination of the kidney led to the diagnosis of arterial TMA in three cases, and glomerular TMA and severe renal cortical necrosis in one case each. Analysis of the relationship between renal histological findings and the prognosis found that three patients with arterial TMA and one patient with severe renal cortical necrosis later developed end-stage renal failure while one patient with glomerular TMA has continued to show normal renal function. CONCLUSIONS: These findings indicate that pathological findings are closely related to the prognosis in cases of nStx-HUS.     

Comparative study of direct polymerase chain reaction, microscopic examination and culture-based morphological methods for detection and identification of dermatophytes in nail and skin samples

The positive rates of dermatophytes isolated and identified by conventional methods are rather low. Moreover, clinical isolates sometimes show atypical morphology, and in such cases microscopic methods are not applicable for identification. The present study was performed to assess the utility of specific polymerase chain reaction (PCR)-based methods for Trichophyton rubrum and Trichophyton mentagrophytes as diagnostic tools for dermatophytoses. Both conventional morphological identification and specific PCR methods based on the nuclear ribosomal internal transcribed spacer (ITS)1 DNA sequence were performed to identify dermatophyte species from clinical specimens of patients who visited Kawasaki Social Insurance Hospital between 16 May and 17 August 2005. Specific PCR methods were also directly applied to clinical specimens, and the results of the two methods were compared. The clinical samples examined consisted of 126 skin scale specimens and 80 nail specimens. The positive rates of culture isolation from clinical specimens were 67% and 33% for skin scale and nail specimens, respectively. In contrast, PCR analysis yielded a positive rate of 100% for clinical isolates from both skin scales and nails, and rates of 95% and 99% were obtained by direct application to clinical specimens. The results of the present study indicated that specific PCR is highly advantageous as a diagnostic tool for detection and identification of dermatophytes on direct application to skin scale or nail specimens.     

Discrimination between His-bundle and the Right Bundle Branch during Electrophysiologic Studies

Background: The purpose of this study was to identify the His-bundle (HB) versus right bundle branch (RBB) during electrophysiologic studies, using the V3 phenomenon, and to compare the timing of HB versus RBB potentials of sinus cycles (His-ventricular [H-V] interval).
Methods: The study enrolled 16 patients without structural heart disease, who underwent electrophysiologic studies during which the H-V interval was within normal limits and the V3 phenomenon was induced during recordings of the HB and the RBB potentials by a multi-electrode catheter. The recording site of the earliest HB potential just before the V3 phenomenon was defined as the branching portion of His bundle (HBBP), the site immediately proximal to the HBBP as the HB, and the site immediately distal to the HBBP as the RBB.
Results: The HBBP was identified in all patients. In all cases but one patient, the H-V interval measured at the HB adjacent to the HBBP was ≥35 ms. However, in 12 patients, the H-V interval measured at the RBB adjacent to the HBBP was also ≥35 ms.
Conclusions: The electrophysiologic identification of HB versus RBB by simultaneous recordings of HB and RBB potentials during induction of the V3 phenomenon was feasible. When the discrimination between HB and RBB was based on the measurement of the H-V interval, the proximal portion of the RBB was frequently misidentified as the HB.