Survival of rats undergoing continuous bile drainage depends on maintenance of circadian rhythm of bile secretion

It is very difficult to collect bile secretions from animals for extended periods of time. We compared the use of saline or water as drinking fluids to sustain the animals, which were being continuously drained of bile. Complete bile drainage was performed in 16 male Wistar rats by surgical intervention. After surgery, 8 rats were given tap water, and the other 8 were given normal saline for water. The rats that received water rapidly lost weight after bile drainage, and all died within 8 days after the operation. In contrast, all rats that drank saline maintained their body weight and survived 14 days or longer after surgery. Serum biochemistry of the rats with water intake on the third day after bile drainage revealed hyponatremia, hypochloremia, and acute renal failure resulting in hyperkalemia. In contrast, electrolyte balance and renal function were normal in the rats with saline intake, and bile was secreted continuously with a circadian rhythm. These results clearly demonstrate that saline as drinking water is essential to the replacement of lost fluids and loss of electrolytes due to bile drainage. Further, saline proved efficacious for sustaining experimental animals undergoing continuous bile collection.

Autonomic nervous function in patients with Meniere's disease evaluated by power spectral analysis of heart rate variability

OBJECTIVE

A hypothesis has been advanced that the autonomic nervous dysfunction (AND) relates to the development of vertigo in Meniere's disease (MD). We also studied the causal relationship between AND and vertigo in MD.

METHODS

We evaluated autonomic nervous function in 17 patients with MD (five men and 12 women ranging in age from 16 to 70 years) by classifying them by their stages of attack and interval of vertigo and with power spectral analysis (PSA) of heart rate variability. Fourteen healthy volunteers were also tested as controls.

RESULTS

At the interval stage, parasympathetic nervous hypofunction and significant depression of sympathetic response due to postural changes from the supine to the standing position were observed in many of those patients. At the attack stage, sympathetic nervous hypofunction was observed in some of the patients.

CONCLUSION

These findings lead us to the conclusion that AND relates to vertigo in MD as a predisposing factor. However, the question of whether AND relates as a trigger or as a consequence of vertigo in MD has not been adequately solved in this study. We will make further studies on circadian variation of autonomic nervous function.

Experimental small bowel transplantation using newborn intestine in rats: II. Revascularization of newborn intestine is independent of vascular endothelial growth factor

BACKGROUND

Fetal and newborn intestine often are revascularized after subcutaneous transplantation without surgical vascular anastomosis. However, the mechanism of this ability remains unclear.

METHODS

First, the ability of natural revascularization in newborn organs was tested. Newborn organs in whole (liver, kidney, heart, intestine, spleen, and pancreas) were grafted i nto the subcuta neous tissue of the adult rat and evaluated histopathologically 2 weeks after transplantation. Second, expression of vascular endothelial growth factor (VEGF) mRNA in the intestinal graft was determined before and after transplantation. Finally, we tested whether the free graft survival of newborn intestine was interrupted by TNP-470, an antiangiogenic agent.

RESULTS

Spleen and intestine were revascularized at a higher rate (91.6%, 75%, respectively), and kidney and heart grafts survived at a lower rate (41.7%, 25%, respectively). But all of liver and pancreas grafts failed to be revascularized. VEGF mRNA was not induced in the course of revascularizing. Furthermore, TNP-470 did not interfere with neovascularization of the newborn intestinal graft in vivo.

CONCLUSIONS

Each organ had an organ-specific angiogenic activity. Neovascularization of intestinal graft was not dependent on VEGF expression.

Two outbreaks of influenza A (H3N2) in a Japanese nursing home in the winter of 1996-1997, with differing vaccine efficacy

Sixty of 128 (46.9%) residents of a nursing home were immunized with two doses of the trivalent split influenza vaccine. They developed 7.4-11.5-fold antibody increases, with a 69-82% protection rate, presenting good immune response rates to the influenza vaccine. Two outbreaks of influenza A (H3N2) occurred. There were no significant antigenic differences among the vaccine strain and the strains isolated from both outbreaks in haemagglutination-inhibition tests, suggesting that the second might have been a reoccurrence. There were no residents who were infected in both outbreaks. The vaccine efficacy against clinical illness in the first outbreak of typical influenza-like-illness (ILI) was 51% (relative risk: 0.49), and the febrile period was reduced significantly by vaccination. In the second outbreak, however, in which all patients had atypical ILI with a high fever but not respiratory symptoms, vaccine efficacy was not apparent for unknown reason.

Nucleotide sequence of thymidine kinase gene of sequential acyclovir-resistant herpes simplex virus type 1 isolates recovered from a child with Wiskott-Aldrich syndrome: evidence for reactivation of acyclovir-resistant herpes simplex virus

Recurrent acyclovir (ACV)-resistant (ACV-r) herpes simplex virus type 1 (HSV-1) infections occurred in a patient with Wiskott-Aldrich syndrome, an X-linked recessive immunodeficiency syndrome composed of three clinical characteristics of immunodeficiency, thrombocytopenia, and an eczematous dermatitis. The patient had severe and recurrent ACV-r herpes simplex and was treated with vidarabine in a satisfactory manner from 1993 to 1997. During the 4-year observation period, two ACV-sensitive (ACV-s) HSV-1 isolates and five ACV-r HSV-1 isolates were recovered. The nucleotide sequence of the thymidine kinase (TK) gene from these sequential ACV-r isolates was compared with the ACV-s isolates. A single nucleotide deletion of cytosine (C) from homopolymer stretch of four C residues between nucleotide 1061 and 1064 of the open reading frame was found in all ACV-r isolates. No other differences were observed in the TK nucleotide sequence between ACV-s and ACV-r isolates. The TK nucleotide sequences of the two ACV-s isolates were identical to each other and those of the five ACV-r isolates were identical to one another. These results suggest that the ACV-r HSV-1 might have derived from the ACV-s strain in the patient body and that TK-associated ACV-r HSV-1 can reactivate from latency.

PCR-RFLP analysis of cytomegalovirus infections associated with bone marrow transplantation in Japanese children

In order to investigate the longitudinal molecular epidemiology of cytomegalovirus (CMV) infections associated with bone marrow transplantation (BMT) in Japanese children, we analyzed 36 CMV strains from 11 cases. Three regions (DNA polymerase, glycoprotein H, and immediate-early regions) of CMV DNA were amplified by polymerase chain reaction (PCR), and amplified products were each digested with two restriction enzymes, followed by electrophoresis. These restriction fragment length polymorphism (RFLP) analyses allowed the differentiation of 36 strains into 13 genotypes. Each patient excreted his or her own CMV with distinct genotype over the study period of up to one year. CMVs of two different genotypes were recovered during a one-month study from one recipient, who received a peripheral blood stem cell transplantation. Although the majority of patients and donors were CMV-seropositive before BMT, multiple CMV infections might not be common and the reactivation of latently infected CMV might be prominent in Japanese children receiving transplants.

Experimental small bowel transplantation using newborn intestine in rats: I. Lipid absorption restored after transplantation of nonvascularized graft

BACKGROUND/PURPOSE

Utilizing the characters of neovascularized activity of newborn organs, the authors developed a rat model of small bowel transplantation with a free graft of newborn intestine into the recipient's omentum.

METHODS

Segmental intestine from newborn rats were grafted into the omentum without vascular anastomosis in a syngeneic combination (n = 19). The transplanted intestine was examined morphologically and electrophysiologically 4 weeks after grafting. Then, recipients' small intestine was totally substituted by the transplanted newborn intestine, and recipients' survival was recorded after orthotopical reconstruction. During the experimental periods, feces of these rats were collected, and total lipid excretion was measured. The short-gut rats, whose small bowel was totally resected, served as a control (n = 12).

RESULTS

Thirteen of 19 grafts (68.4%) were judged as a histologically mature intestine. They showed typical slow waves that were identical to those of native small intestine. After all of the mature grafts were interposed, six recipients (46.2%) survived longer than 15 weeks. Control short gut animals severely lost weight and died except for one.

CONCLUSION

Newborn intestinal transplantation could restore severe weight loss in the short-gut rats and save them.

Chronopharmacology for deoxyspergualin: toxicity and efficacy in the rat

BACKGROUND

Deoxyspergualin (DSG), a potent immunosuppressive drug, has been clinically used as a rescue therapy for acute graft rejection. However, DSG has severe adverse effects that limits its use. Here, we examined the optimized therapeutic protocol for DSG using chronopharmacological profiles of it.

METHODS

First, a dosing time-dependent difference in the toxicity and efficacy of DSG was determined using a heterotopic heart transplantation model. Second, chronokinetics of DSG were examined to reveal the mechanism for dosing time-dependent differences in the effect.

RESULTS

In rats treated with DSG at the active period, bone marrow suppression and damage of small intestine were significantly severe. However, no significant difference was found in cardiac allograft survival and pharmacokinetics according to the timing of drug administration.

CONCLUSIONS

The toxicity of DSG varied with the dosing time, whereas its efficacy did not. The chronopharmacological approach may provide merits for immunosuppressive therapy with DSG in clinical organ transplantation.

Increased expression of phospholipase D1 mRNA during cAMP- or NGF-induced differentiation in PC12 cells

The rat pheochromocytoma PC12 cells have been employed as a useful model to study neuronal differentiation. To gain insight into the molecular events involved in extension of neurites, the differential expression of phospholipase D (PLD) isozymes were examined in cyclic AMP- or nerve growth factor (NGF)-treated PC12 cells. When the cells were incubated with dibutyryl cyclic AMP (dbcAMP), almost all the cells displayed prominent neurite outgrowth at 24 h. The neurites developed in NGF-treated cells at 24 h were shorter than those in the cells treated with dbcAMP. However, most of the NGF-treated cells extended long neurites at day 5. The rPLD1b mRNA increased within 6 h following dbcAMP treatment and maintained a high level up to 24 h. In contrast, the levels of rPLD1a and rPLD2 mRNAs were rather consistent throughout the time course examined. However, when the cells were treated with NGF, rPLD1a and rPLD1b mRNAs, but not rPLD2 mRNA, increased within 2 days and remained elevated up to 5 days. These results suggest the possible implication of PLD1 in PC12 cell differentiation.

Protective effect of gamma-glutamylcysteinylethyl ester on dysfunction of the selenium-deficient rat heart

We investigated the protective effect of intracellular GSH against cardiac dysfunction in selenium (Se)-deficient neonatal rats and cultured fetal rat myocytes. A Se-deficient diet with or without daily subcutaneous injections of gamma-glutamylcysteinylethyl ester (gammay-GCE) (a membrane-permeating GSH precursor) was given to rats from gestation day 4 via the dam to postnatal day 14. Se deficiency induced a 62% incidence of electrocardiographic abnormalities such as sinus arrhythmias or extrasystole, a 63% reduction in dP/dt in the left ventricle, and an increase in thiobarbituric acid reacting substances (TBARS), but no ultrastructural cardiac lesions were observed. Administration of gamma-GCE increased the intracellular GSH concentration ([GSH]i) of both neonatal rat hearts and cultured fetal rat cardiac myocytes. gamma-GCE-like sodium selenite prevented the cardiac dysfunction and the TBARS increment. gamma-GCE also prevented H2O2 toxicity in the cultured myocytes. The Vmax, but not the Km, for GSH of Se-dependent GSH peroxidase (Se-Gpx) activity in Se-deficient rat heart homogenates was one-third that of normal rat heart homogenates. Although gamma-GCE did not affect the Se-Gpx Vmax and Km for GSH, it did induce a substantial and significant increase in [GSH]i, which was postulated to increase the velocity of H2O2 decomposition by Se-Gpx activity 1.6-fold. These data suggest that the increase in [GSH]i may have played a role in preventing the TBARS increase and cardiac dysfunction in Se-deficient rats.

[Postoperative prophylactic intravesical instillation of tetrahydropyranyl-adriamycin (THP) for superficial bladder cancer]

Intravesical instillation of tetrahydropyranyl-adriamycin (THP) was performed on 51 patients with superficial bladder cancer after transurethral resection (TUR) for prophylaxis of recurrence. The instillation was carried out with 20 mg of THP dissolved in 40 ml of distilled normal saline. Instillation was performed once 24 hours postoperatively, 9 times every 2 weeks, and 8 times every 4 weeks. These drugs were instilled for 30 to 60 minutes. The recurrence-free survival at 1, 2 and 3 years was 74.5%, 64.6% and 58.0%, respectively. Side effects of THP instillation were observed in only 4 cases (7.8%) as slight urinary frequency or micturition pain. Cases involving 5 or more tumors, or tumors measuring 3 cm or larger, more frequently demonstrated recurrence. The cases that did not respond to preoperative intravesical instillation of THP demonstrated a high frequency of recurrence. Intravesical instillation of THP as a prophylaxis against recurrence of superficial bladder cancer was effective in selected patients.

Ultrastructural localization of megalin in the rat cochlear duct

Megalin is an endocytic receptor predominantly expressed in the kidney proximal tubule cells. In the present study, localization of megalin was examined using a post-embedding immunogold method in the rat cochlear duct. Marginal cells of the stria vascularis were labeled on the apical surface, but not on the basolateral surface. This localization pattern resembles kidney proximal tubule cells. Immunoreactivity was also detected on various other cells, including epithelial cells of the spiral prominence and epithelial cells of Reissner's membrane. In contrast, virtually no gold particles were seen on intermediate cells and basal cells of the stria vascularis, mesothelial cells of Reissner's membrane or fibrocytes in the lateral wall. Also unlabeled were cells in the tympanic wall of the cochlear duct, including sensory cells and supporting cells of the organ of Corti. The present findings show the involvement of megalin in endocytosis of marginal cells and are suggestive of different uptake mechanisms for aminoglycosides in the kidney proximal tubule cells and in the cochlear sensory cells.

Study on Chlamydia trachomatis infection among students and pregnant women in Japan: a step toward developing a reliable method for sexual behavior study

2450 sera from students and 5215 sera from pregnant women were examined for the presence of Chlamydia trachomatis (CT) antibody. CT antibody positive rates were less than 5% with the students and 24.5% with the pregnant women suggesting the latter is significantly higher than former. The results provided a base for discussing possibility of using CT infection as a reliable method for studying sexual behavior.

[Prognostic significance of EGFR and p53 expression, and angiogenesis in laryngeal squamous cell carcinoma]

PURPOSE

To estimate the influence of EGFR, p53, and angiogenesis to the survival of laryngeal cancer patients.

PATIENTS

Ninety-seven laryngeal cancer patients who received initial treatment at Gifu University Hospital from 1986 to 1996. Patients were classified as follows: T2, 51; T3, 35; T4, 13.

METHOD

Using monoclonal antibodies against EGFR, p53, and factor VIII, respectively, immunohistochemical staining was performed on surgically obtained biopsy specimens. Univariate and multivariate regression analyses in accordance with Cox proportional hazards model were performed to adjust for the possible confounding effects and interactions of each factor. Three different end points, i.e. any death, cancer-related death, and cancer relapse (either local recurrence or distant metastasis), were used to evaluate overall survival, cause-specific survival, and relapse-free survival, respectively.

RESULT

In univariate analysis, sex (P = 0.0052), age (P = 0.0038), T stage (P = 0.0096) and N stage (P = 0.0261) were significantly correlated with overall survival; sex (P = 0.0076), T stage (P = 0.0167) and factor VIII expression (P = 0.0443) were related to cause-specific survival; T stage (P = 0.0005) and EGFR expression (P = 0.0103) were related to relapse-free survival. In multivariate analysis, supraglottis (P = 0.0296) and factor VIII expression (P = 0.0345) were significantly correlated with overall survival; supraglottis (P = 0.0333), T stage (P = 0.0179) and factor VIII expression (P = 0.0134) were significantly correlated with cause-specific survival; T stage (P = 0.0166), chemotherapy (P = 0.0087) and EGFR expression (P = 0.0016) were significantly correlated with relapse-free survival.

CONCLUSION

The present study confirmed that multivariate analysis in accordance with the Cox proportional hazards model revealed that angiogenesis was an independent predictor of overall survival and cause-specific survival, and that EGFR expression was an independent predictor of relapse-free survival in patients with T2, T3 or T4 laryngeal cancer.

Effects of corticosteroid, contrast medium and ATP on focal microcirculatory disorders of the cochlea

We evaluated the ability of various drugs to prevent the decrease in focal cochlear blood flow induced by photochemical reaction and investigated the mechanisms underlying this decrease. By means of a photochemical reaction, which produces reactive oxygen species, focal lesions measuring about 1 mm in diameter were induced in the lateral wall of the guinea pig cochlea. The protective effects of hydrocortisone, amidotrizoate and ATP on cochlear blood flow and cochlear vascular conductance changes were evaluated by using a non-contact laser flowmeter. Cochlear blood flow and cochlear vascular conductance were decreased to 65.1+/-4.9% (mean +/- S.E.M.) and 57.0+/-3.7% (mean +/- S.E.M.) of the initial level 30 min after the start of the photochemical reaction, respectively. Hydrocortisone significantly prevented the decline in the cochlear blood flow and cochlear vascular conductance and reduced the area of stria vascularis degeneration in a dose-dependent manner. Neither amidotrizoate nor ATP significantly prevented the decrease in cochlear blood flow or cochlear vascular conductance. Hydrocortisone was more effective than vasodilators or other agents which increase cochlear blood flow in preventing the photochemically induced decrease in cochlear blood flow. This might be due to the antioxidative effects of hydrocortisone.

Scanning electron microscopic study of the postnatal development of the rabbit cochlea, with an emphasis on innervation

The development of nerve fiber arrangements of the organ of Corti was studied in rabbits 1, 3, 5, 7 and 12-days-old using thick sections from celloidin-embedded cochleas which were examined under a scanning electron microscope. The arrangements of nerve fibers varied with developmental age. The tunnel spiral bundle was thick and loosely collected in the immature cochlea. The outer spiral fibers were recognized even in the narrow space of Nuel in the one-day-old cochlea. As Nuel's space is extending, the fibers course along the medial side of Deiters' cells. The arrangement of the outer spiral fibers was irregular and sparse in the five-day-old cochlea, in contrast to the regular parallel pattern of the adult cochlea. Adult-like parallel arrangement of the outer spiral fibers was seen in the twelve-day-old cochlea. In the three-day-old cochlea, irregularly running nerve fibers were seen along the outer spiral fibers. They may be efferent axons which develop afterwards. Club-like immature nerve endings were recognized at the base of the outer hair cells in the seven-day-old cochlea. Some fibers climbed high up along the medial wall of the outer hair cells. A nearly mature pattern was seen in the twelve-day-old cochlea. This study confirms previous reports on the development of cochlear innervation.

Facial nerve stimulation by a cochlear implant in a hemodialysis patient with bone of low mineral density

Facial nerve stimulation by an activated cochlear implant was noted in a 56-year-old patient who had undergone cochlear implant with a Nucleus 22 implant 2 years previously as treatment for total sensorineural hearing loss following meningitis at age 54. Past history was complicated by total renal failure for which hemodialysis had been required during the past 13 years. Facial spasm occurred 5 months postoperatively with activation of the basal electrodes (channels 13 and 15 of the implant). The facial stimulation was eliminated by deprogramming these electrodes. High-resolusion computed tomography (CT) scanning was unable to demonstrate lucency of the otic capsule and cochlear ossification, but basal electrodes of the implant could be identified near the labyrinthine segment of the facial nerve. To further evaluate bone changes in the patient, the total and regional bone mineral density (BMD) of the head and radius was measured by dual energy X-ray absorptiometry. All BMD values of the patient were markedly low when compared to those of 62 other hemodialysis patient. These findings demonstrate that facial nerve stimulation can occur in the presence of low impedance due to cortical bone changes induced by long-term hemodialysis.

Respiratory syncytial virus infection in children with acute respiratory infections in Zambia

Epidemiological research on respiratory syncytial virus (RSV) infections in children was carried out at the Virology Laboratory, University Teaching Hospital (UTH), in Lusaka, Zambia, from January-December 1996. Specimens including 736 nasal washings and 2424 throat swabs were collected from children with acute respiratory infections (ARI) and tested for RSV by enzyme immunoassay and by virus isolation. RSV was isolated in 62 (4.1%) of 1496 throat swabs collected from March to September and was detected in 99 (16.3%) of 609 nasal washings from March to November. The average RSV isolation rate was 2.6% and the average RSV detection rate was 13.5%. The highest RSV isolation (8.1%) and detection (30.5%) rates were in June 1996. RSV antibody in the 278 serum specimens collected from Zambian children, who were hospitalized in the paediatric ward, UTH, was detected using a standard neutralization test. The antibody positive rate was 60-80% in children > 4 years. It is evident that RSV is one of the main causal agents of ARI in children in Zambia.

Increase in natural killer cell activity following living-related liver transplantation

We monitored the serial changes of natural killer cell (NK) activity in eight recipients of living-related liver transplantation. The HLA types of all eight patients were haplotypically identical with those of their donors. Tacrolimus and methylprednisolone were used for immunosuppression. The NK activity before transplantation was 24.1 +/- 20.2% which is surprisingly low when compared with the value for normal individuals (67.7 +/- 13.2%, P < 0.01) or a liver dysfunction group (49.4 +/- 21.9%, P < 0.05). Serial changes in NK activity revealed a minimum of 6.1 +/- 3.6% 1 week after transplantation, gradually increasing to 49.2 +/- 12.5% at 2 months after transplantation. These results suggest that the diseased liver might play an important role in the suppression of NK activity.

Increased carbon monoxide in exhaled air of subjects with upper respiratory tract infections

Viral infection may induce the expression of heme oxygenase, resulting in increased carbon monoxide (CO) formation. CO may be produced by various cells of the upper and lower respiratory tract and may be detected in the exhaled air. Therefore, exhaled CO concentrations were measured on a CO monitor by vital capacity maneuver in subjects with upper respiratory tract infections (URTIs) and in nonsmoking and smoking healthy control subjects. At the time of symptoms of URTI, exhaled CO concentrations were 5.6 +/- 0.4 ppm and decreased to 1.0 +/- 0.1 ppm during recovery. Recovery values of exhaled CO were similar to those in age-matched nonsmoking healthy control subjects (1.2 +/- 0.3 ppm). Smoking healthy control subjects had the highest levels of exhaled CO concentration among the groups (18.5 +/- 2.5 ppm). These findings suggest that symptomatic URTIs increase the concentration of CO in exhaled air. This may reflect the induction of heme oxygenase that has an antiviral effect in the airways.

Tone burst-evoked otoacoustic emissions in cats with acoustic overstimulation and anoxia

Transient evoked otoacoustic emissions (TEOAE) produced by a 2 kHz tone burst could be detected in 30 out of 37 ears (81% detectability) in 21 cats. The amplitude of tone burst-evoked TEOAE was saturated at a stimulus level between 45 and 50 dB SPL and the latency time of peak amplitude was 6.23 ms on average (5.53-7.28 ms). The effects of pure tone overstimulation and short-term anoxia on the tone burst-evoked TEOAE in cats were evaluated. A permanent detection threshold shift of the TEOAE was confirmed at 24 h and 1 week after the overstimulation at 125 dB SPL. In these cases, damaged first row outer hair cells and inner hair cells were observed over an average length of 3.3 mm (16% of the entire cochlear length) by scanning electron microscopy. These findings suggested that the TEOAE can detect localized cochlear hair cell damage. A temporary detection threshold shift of the TEOAE was observed after the overstimulation at 105 dB SPL, and the threshold shift recovered in 107.5 min on average. In the short-term anoxia trial, the TEOAE amplitude started to decrease 45-90 s after the anoxia and recovered completely when the duration of anoxia was under 1 min. However, the TEOAE amplitude did not recover pre-anoxia values (it remained below 80% of its initial value) after 5 min when the anoxia was over 2 min. These findings demonstrated that the detection threshold and amplitude of the TEOAE were also affected by metabolic changes of the cochlear hair cells. Tone burst-evoked TEOAE are useful for the evaluation of localized histological and functional damage of the cochlear hair cells.