Poly(adenosine diphosphate-ribose) synthetase inhibitor 3-aminobenzamide alleviates cochlear dysfunction induced by transient ischemia

The present study was undertaken to determine the possible deleterious role played by poly(adenosine diphosphate-ribose) synthetase (PARS) in cochlear ischemia-reperfusion injury. Transient ischemia of the cochlea was induced in albino guinea pigs for 15, 30, or 60 minutes by pressing the labyrinthine artery at the porus acusticus internus. The animals were given intravenous 3-aminobenzamide (a PARS inhibitor) or physiological saline solution I minute before the onset of reperfusion. The compound action potential thresholds were measured before the onset of ischemia and 4 hours after the onset of reperfusion. A statistically significant reduction in the postischemic compound action potential threshold shift was observed in the animals treated with 3-aminobenzamide after 15 or 30 minutes of ischemia, whereas no statistical difference was found after 60 minutes of ischemia. These results suggest that excessive activation of PARS exerts deleterious effects on the cochlear injury induced by transient ischemia.

123I-IMP SPET in the diagnosis of primary central nervous system lymphoma

We reviewed N-isopropyl-p-[123I]iodoamphetamine (123I-IMP) single-photon emission tomography (SPET) images of brain tumours and assessed the usefulness of 123I-IMP SPET for the diagnosis of primary central nervous system (CNS) lymphoma. We analysed 52 tumours that showed enhancement on magnetic resonance imaging: 11 malignant lymphomas, 3 anaplastic astrocytomas, 17 glioblastomas, 12 meningiomas, 4 metastatic brain tumours and 5 other brain tumours. 123I-IMP uptake in the tumours on early (15-min) and delayed (4-h) scans was visually classified as high, moderate or low as compared with the contralateral brain cortex. Early and delayed 123I-IMP uptake ratios comparing tumours with contralateral brain cortex (T/N ratio) were also calculated. In malignant lymphomas, the visual uptake of 123I-IMP was moderate to high on the delayed scans. The delayed T/N ratios were significantly higher than the early ratios (P<0.05) and all lymphomas, with the exception of one small one, had delayed ratios greater than 0.9. In non-lymphomatous tumours, the visual uptake of 123I-IMP was low on the delayed scans. The delayed T/N ratios were significantly lower than the early ratios (P<0.01) and all non-lymphomatous tumours had delayed ratios of less than 0.8. The T/N ratios of lymphomas were significantly higher than those of non-lymphomatous tumours on both early and delayed scans (P<0.0001). These results suggest that 123I-IMP SPET may be a useful tool in the differential diagnosis of primary CNS lymphoma.

[Transsphenoidal surgery assisted by navigation system]

Microneurosurgical technique combined with precise localization of lesions, can minimize the invasiveness of neurosurgical procedures. This report describes the usefulness of the neuronavigation system in transsphenoidal surgery. Nineteen transsphenoidal operations for sellar lesions including pituitary adenoma, clival chordoma, Rathke's cleft cyst and suprasellar germinoma were assisted by the optical tracking system (OTS). Operations were performed either through the sublabial or the endonasal approach using an operative microscope and, to a certain extent, the endoscope. All five microadenomas were totally removed. The tumors could be precisely localized by the navigation system. Four out of seven macroadenomas were totally removed. The operations were assisted effectively by the excellent guidance to the lateral margin of the tumors and the internal carotid arteries provided by the navigation system. The endonasal approach, in which the surgeon looks through a nostril at the sellar floor obliquely, was especially facilitated by the three-dimensional view provided by the system. The navigation system, however, was not useful in estimating the amount of the suprasellar residual tumor because of the dislocation that occurred during the tumor removal.

[Drug sensitivity, conjugative R plasmids and plasmid profiles of Salmonella isolated from humans with infectious enteritis]

Using 92 Salmonella strains isolated from patients suspected of having infectious diseases of the intestinal tract who visited 13 hospitals in Japan during the six years between 1991 and 1996, we investigated the drug susceptibility, prevalence of conjugative R plasmid, and the plasmid profiles. 1) Of the bacterial isolates tested, 52.2% showed drug-resistance. Regarding the drug-resistance patterns, 70.8% of the isolates were resistant to a single drug, while 29.2% were multi drug-resistant. 2) Dividing the resistance patterns by the serotypes, among Salmonella Enteritidis isolates, single-drug resistance to SM was the most frequent, being detected in 27 isolates. Single-drug resistance to NA and two-drug resistance to SM/TC were the second-most frequent, each being detected in isolates. Among Salmonella Hadar isolates, four isolates showed two-drug resistance to SM/TC, and one isolate showed single-drug resistance to TC. Among Salmonella Typhimurium isolates, one isolate each showed three-drug resistance to ABPC/CER/KM and KM/TC/CP. Among Salmonella Agona isolates, one isolate each showed two-drug resistance to SM/TC and single-drug resistance to SM. Among Salmonella Derby isolates, two isolates showed single-drug resistance to SM. 3) The prevalence of conjugative R plasmid was investigated in 48 drug-resistant isolates, and six isolates (12.5%) contained the plasmid. 4) The prevalence of the plasmid was investigated in 29 drug-resistant S. Enteritidis isolates, and 22 isolates (75.9%) contained the plasmid. These isolated were classified by the plasmid profiles into types H1 to H7. 5) Regarding the plasmid profiles of the S. Enteritidis isolates, a position corresponding to 60 Kbp was the most frequently detected in 90.5%.

[A case report of a successful surgical treatment for infective endocarditis involving four valves in a elderly patient with ventricular septal defects]

A 72-year-old female was examined because of acute congestive heart failure. Echocardiogram revealed vegetations on aortic and pulmonary valve, regurgitation of four valves, and perimembraneous ventricular septal defect. Aortic valve replacement, mitral valve replacement, repair of tricuspid valve using a Carpentier ring, partial resection of pulmonary valve, and direct closure of VSD was performed. Pathological finding of resected valves showed acute endocarditis. A patient resumed social activities after surgery.

Down's syndrome with myelodysplastic syndrome showing t(7;11)(p13;p14)

We report a boy with Down's syndrome (DS) who developed myelodysplastic syndrome (MDS) after spontaneous remission of transient myeloproliferative disorder (TMD) at birth. Chromosomal analysis of the blasts in the MDS phase demonstrated t(7;11)(p13;p14) which had not been detected in the TMD phase. NUP98-HOXA9 chimera mRNA, which is known to be involved in t(7;11)(p15;p15) translocation in acute myeloid leukemia (AML), was not detected by reverse transcriptase-polymerase chain reaction, and NUP98 rearrangement was not detected by Southern blot analysis of the blasts in the MDS phase. Reciprocal translocation is very rare in AML/MDS in DS, and the t(7;11)(p13;p14) found in our patient was different from the recurrent translocation t(7;11)(p15;p15) previously reported.

Effect of 7-nitroindazole upon cochlear dysfunction induced by transient local anoxia

The purpose of the present study was to further elucidate how nitric oxide (NO) is involved in cochlear anoxia-reperfusion injury. Transient local anoxia of the cochlea was induced in albino guinea pigs for 15, 30, or 60 minutes by transiently compressing the labyrinthine artery through a skull base approach. 7-Nitroindazole (7NI), a relatively selective neuronal nitric oxide synthase (nNOS) inhibitor. was intraperitoneally administered to the guinea pigs 30 minutes before the onset of local anoxia. The compound action potential (CAP) thresholds were measured before the administration of 7NI and 4 hours after the onset of reperfusion. A statistically significant reduction in the postanoxic CAP threshold shift from the preadministration value was observed in the 7NI-administered animals as compared with the control animals after 15- and 30-minute periods of anoxia. These results confirm the involvement of NO and nNOS in the cochlear injury induced by transient local anoxia.

Peroxiredoxin I expression in oral cancer: a potential new tumor marker

This study investigates the applicability of the novel antioxidant protein, peroxiredoxin (Prx) I as a marker for tumor status in oral squamous cell carcinoma (SCC). Samples from 53 patients with SCC in the oral cavity were examined by immunohistochemistry. Correlations between the expression level of Prx I and proliferating cell nuclear antigen (PCNA), the clinical features of tumors, and their histopathological classifications were statistically analyzed. Cases exhibiting low Prx I expression level included significantly more with larger tumor mass cases (T-category, P=0.004), positive lymph node metastasis (N-category, P=0.015), advanced stage (P=0.002), and poorly differentiated cells (P=0.020). There was no significant difference between Prx I expression and the other indices.

Levels of beta-human chorionic gonadotropin in cerebrospinal fluid of patients with malignant germ cell tumor can be used to detect early recurrence and monitor the response to treatment

BACKGROUND

Tumor marker-producing germ cell tumors of the central nervous system are malignant and require radiation and/or chemotherapy. Although serum beta-human chorionic gonadotropin (hCG) has been used to monitor the course of treatment, the levels of beta-hCG in the cerebrospinal fluid (CSF) have not been measured routinely in the clinic. To determine whether they can be used to evaluate parameters of tumor status, such as progression or response to therapy, levels of beta-hCG in the serum and CSF of patients with germ cell tumors were studied.

METHODS

Fifty-four paired samples of CSF and serum were taken from seven patients with germ cell tumor and their beta-hCG levels were measured. Beta-hCG was negative in both serum and CSF in 11 instances and the levels in the other 43 paired samples were analyzed for any correlation or relationship to therapy. They were also compared with the clinical courses.

RESULTS

The mean CSF beta-hCG level was 11.5 mIU/ml, which was significantly higher than the level in serum (3.5, p = 0.002). In all the paired samples except for one time point, the level in CSF was higher than that in serum. Out of 43 instances where the beta-hCG level in CSF was elevated, the level in serum was elevated in only 16 (37.2%). Among cases of recurrent malignant germ cell tumor, there were nine instances of recurrence or progression despite therapy. In all five instances where beta-hCG CSF levels were measured, the levels were elevated prior to any increase or detectability of the serum values.

CONCLUSION

It seems likely that the level of beta-hCG in CSF is a good marker for monitoring tumor recurrence or evaluation of treatment results.

Effect of calmodulin antagonists on the compound action potential of the cochlea

This study aimed to evaluate the effect of calmodulin antagonists on the threshold of the compound action potential (CAP) and the functional recovery of the cochlea after transient ischemia. When trifluoperazine and W-7 were administered to albino guinea pigs with perilymphatic perfusion, these drugs did not significantly affect the CAP thresholds. Transient cochlear ischemia of 30-min duration was obtained via a skull base approach. Although trifluoperazine significantly ameliorated the post-ischemic CAP threshold shifts 4 h after the onset of reperfusion, 1 to 50 microM W-7 did not affect the CAP threshold shifts. These results suggest that the action antagonizing calmodulin has no effect on the CAP threshold, while the role that calmodulin plays in cochlear ischemia-reperfusion injury still remains unclear.

[Management strategy for patients with coronary artery disease associated with valve disease]

BACKGROUND

The indication of combined operation of coronary artery bypass (CAB) and valve surgery is controversial.

METHODS

Between April 1992 and January 2000, 13 patients underwent a combined operation with CAB and valve replacement, and 4 patients (2 were overlapped) who had had a previous CAB underwent a reoperative valve replacement.

RESULTS

One patient who underwent AVR and reCAB 11 years after the initial CAB died. Another patient with preoperative MRSA pneumonia and received MVR and CAB died 4 months after surgery with MRSA sepsis. However, others showed an excellent post-operative course. The causes of necessitating the reoperation were: unawareness of aortic stenosis at the initial emergency CAB in 1 patient, progression of aortic stenosis in 1 patient, progression of aortic regurgitation in 1 patient, and progression of mitral regurgitation in 1 patient.

CONCLUSION

The results of the combined CAB and valve replacement operation were acceptable. Patients with mild-moderate valve disease should be considered as candidates for valve surgery at the time of CAB.

A case report of FSH-producing nasal ectopic pituitary adenoma extending to the frontal cranial fossa

We report the first case of an ectopic pituitary adenoma in the nasal cavity that produced follicle-stimulating hormone (FSH). A 60-year-old man complaining of left nasal bleeding had a polypoid tumor in the left nasal cavity. Findings of computed tomographic scanning and magnetic resonance imaging showed that the tumor originated from the olfactory cleft, occupied the nasal cavity, and extended to the frontal cranial fossa. Results of histologic examination suggested ectopic pituitary adenoma. Magnetic resonance imaging results showed the pituitary gland to be normal. Electron microscopy findings demonstrated a large number of secretory granules in the tumor cells that were positive for FSH on immunohistochemical analyses. Serum gonadotropin levels were normal, and no clinical signs of hypersecretory syndrome were noted. The above findings led us to establish the diagnosis of FSH-producing ectopic pituitary adenoma. The patient underwent craniofacial resection of the tumor followed by an uneventful recovery. The pathologic findings and clinical course of the case were comparable to those of FSH-producing adenomas arising from the pituitary gland.

The contribution of phospholipase A2 to the cochlear dysfunction induced by transient ischemia

The objective of the present study was to examine whether mepacrine, a commonly used phospholipase A2 inhibitor, decreases ischemic damage to the cochlea. Transient ischemia of the cochlea was induced in albino guinea pigs for 15, 30 or 60 min by pressing the labyrinthine artery at the porus acusticus internus. The animals were intraperitoneally given mepacrine or physiological saline solution (PSS) 20 min prior to ischemia. Although mepacrine failed to alleviate the post-ischemic threshold shift of compound action potential (CAP) in case of 60 min ischemia, a statistically significant reduction in the CAP threshold shift was observed in the mepacrine-treated animals after 15 and 30 min ischemia. However, there was no statistically significant difference in the post-ischemic threshold shift of cochlear microphonic between the mepacrine-given and the PSS-given animals. Furthermore, mepacrine partially alleviated ischemia-induced swelling of radial afferent dendrites of primary auditory neurons. These results suggest that excessive activation of phospholipase A2 plays an injury-producing role at least by enhancing excitotoxicity in ischemia-reperfusion injury of the cochlea.

Hydroxyl radical formation in the perilymph of asphyxic guinea pig

To elucidate the role of hydroxyl radical (.OH) species in the generation mechanism of the cochlear pathology induced by transient asphyxia and subsequent re-ventilation, the concentrations of 2,3-hydroxybenzoic acid (DHBA) and 2,5-DHBA, major products arising from the attack of .OH upon salicylate, were measured in the perilymph of the guinea pig by the high performance liquid chromatography-electrochemical/UV method. The mean value of 2, 3-DHBA concentration in the perilymph significantly increased from the pre-asphyxic level (6.4 microM) to 7.6 microM and 8.8 microM during asphyxia of 3 min duration and at 5 min after the onset of re-ventilation, respectively. The 2,5-DHBA concentration was 7.9 microM before asphyxia, and also significantly increased to 11.5 microM and 16.2 microM during and after asphyxia, respectively. These results strongly indicated that .OH was generated in the perilymph of the asphyxic and re-ventilated guinea pig cochlea, and the significance of this increased .OH in generating anoxia and re-perfusion injury is discussed with respect to iron and oxygen-derived free radicals.

An evaluation of neurobehavioural problems as perceived by family members and levels of family stress 1-3 years following traumatic brain injury in Japan

OBJECTIVE

To ascertain the proportion of patients with traumatic brain injury (TBI) admitted to a Japanese district hospital and to evaluate the levels of stress and anxiety in fami ies living with those TBI patients.

DESIGN

A retrospective study of patients admitted to hospital from April 1995 to March 1997 and a questionnaire study of family members of survivors.

SETTING AND SUBJECTS

All patients referred or transferred to the Emergency Department at the Saga Medical School Hospital, Japan with a primary diagnosis of TBI were studied. Family members living with TBI patients were sent questionnaires.

MAIN OUTCOME MEASURES

The Barthel Index, the Patient Competency Rating Scale, the modified Caregiver Strain Index and the Hospital Anxiety and Depression Scale.

RESULTS

There were 34 patients who required hospitalization for care relating to TBI. Of these, nine family members took part in the questionnaire study. Three carers reported fairly high levels of stress and another three carers were considered to be at risk of anxiety and depression. There was a tendency for family members who reported that patients had difficulties in performing behavioural tasks to have higher levels of stress themselves.

CONCLUSION

These preliminary results showed that family members experienced certain levels of stress and were also at risk of anxiety and depression. The impact of TBI on families as well as patients should receive more attention.

Induction of apoptosis in glioma cells by recombinant human Fas ligand

OBJECTIVE

Fas ligand (FasL) belongs to the tumor necrosis factor family and has the ability to induce apoptosis in susceptible target cells by binding to its receptor, Fas. It has been demonstrated recently that the FasL/Fas system plays a pivotal role in the cytocidal activity of T lymphocytes in the immune system. FasL may act as a cytotoxic effector molecule to Fas-expressing malignant tumor cells. We reported previously that Fas is commonly expressed in human brain tumor cells. In this study, we examine the possible application of FasL to therapy for malignant brain tumors.

METHODS

To develop an expression system yielding large amounts of FasL, we constructed a baculovirus vector containing complementary deoxyribonucleic acid of human FasL under the control of a polyhedrin promoter. We produced human FasL in Spodoptera frugiperda (Sf9) insect cells infected by the recombinant baculovirus carrying FasL complementary deoxyribonucleic acid and studied the cytocidal activity of FasL against the T98G human glioblastoma cell line.

RESULTS

FasL expression in Sf9 cells was confirmed immunocytochemically with rabbit antibody raised against the cytoplasmic domain of human FasL. The FasL released into the supernatant of cultured Sf9 cells was also verified by Western blotting, and it specifically induced apoptosis in T98G cells. The induced apoptosis by recombinant human FasL was confirmed by annexin V-fluorescein isothiocyanate staining.

CONCLUSION

The present results suggest that the induction of apoptosis by the Fas/FasL system could be a new strategy for the treatment of malignant brain tumors, which are resistant to conventional therapies.

c-Abl expression in oral squamous cell carcinomas

c-Abl is proto-oncogene product. c-Abl has roles in signal transduction, cell cycle regulation, and inhibition of apoptosis. There are many reports about c-Abl function in hematopoietic cells, but few are concerned with solid tumors. In the present study, biopsy specimens from 44 patients with oral squamous cell carcinomas were subjected to immunohistochemistry, and the expression levels of c-Abl were correlated with clinicopathological features. Statistical analyses revealed that c-Abl expression was significantly associated with T-category (p = 0.011), sex (p = 0.014), and differentiation (p = 0.007), but no significant difference was observed with N-category, age, primary tumor region, or the other histological gradings. The low c-Abl expression group included more T4, male, and poorly differentiated cases. There was a trend towards longer tendency survival in the high expression group, but the difference was not significant. We conclude that c-Abl is a good candidate for a tumor-expansion marker.

GAL4/UAS-WGA system as a powerful tool for tracing Drosophila transsynaptic neural pathways

Visualization of specific transsynaptic neural pathways is an indispensable technique for understanding the relationship between structure and function in the nervous system. Here, we demonstrate the application of the wheat germ agglutinin (WGA) transgene technique for tracing transsynaptic neural pathways in Drosophila. The intracellular localization of WGA was examined by immunoelectron microscopy. WGA signals were detected in granule-like structures in both the outer photoreceptor cells expressing WGA and the second-order laminar neurons. Misexpression of tetanus toxin (TNT), which inactivates N-synaptobrevin, in the outer photoreceptor cells resulted in the elimination of on/off transients in electroretinogram (ERG) recordings and in a great reduction in WGA transfer into laminar neurons, suggesting that anterograde WGA transsynaptic transfer is dependent mainly on synaptic transmission. Retrograde WGA transfer was also detected upon its forced expression in muscle cells. WGA primarily expressed in muscle cells was taken up by motoneuron axons and transported to their cell bodies in the ventral nerve cord, suggesting that WGA can trace motoneuronal pathways in combination with the muscle-specific GAL4 driver. Thus, the GAL4/UAS-WGA system should facilitate the dissection of the Drosophila neural circuit formation and/or synaptic activity in various regions and at various developmental stages.

Hypermethylation of p16 and p15 genes and RB protein expression in acute leukemia

Both p16 and p15, encoded by genes located on chromosome 9p21, are inhibitors of cyclin-dependent kinases 4/6 (CDK4/6) and upstream regulators of RB function, and set up the RB/p16 tumor suppressive pathway, which is abrogated frequently in human neoplasms, either through inactivation of the RB or p16 tumor-suppressor protein, or alteration of the cyclin D1 or CDK4 oncoproteins. In hematological malignancies, deletion of p16/p15 locus has been shown to be highly specific to lymphoid malignancies, and more particularly to T-cell acute lymphoblastic leukemia (T-ALL). However, in the other subsets of ALL, deletions of p16 and p15 are relatively rare events. To investigate whether these genes are inactivated by methylation of the 5' CpG islands, we examined 35 leukemia cell lines and 29 childhood acute myeloid leukemia (AML) patients by Southern blot, polymerase chain reaction (PCR) and Western blot analyses. We found methylation of p16 in 12 (50%) of 24 ALL cell lines, 5 (50%) of 10 AML cell lines without homozygous deletion of p16, and 11 (38%) of 29 AML patients. Those leukemia cell lines subjected to p16 methylation were found to have lost p16 protein expression. The p15 gene was methylated in 10 (34%) of 29 ALL cell lines, 6 (60%) of 10 AML cell lines without homozygous deletion of p15, and 15 (52%) of 29 AML patients. These results revealed the frequent methylation of p16 and p15 genes in B-ALL and AML despite a low frequency of p16 and p15 deletions and mutations in these leukemias. In the study for expression of RB protein, we found no expression of RB in 4 of 16 leukemia cell lines. Inactivation of the p16 gene was found in all the cell lines with expression of RB. Neither amplification nor rearrangement of cyclin D1 gene was found in any cell lines. These results suggest that inactivation of p16 and p15 genes is one of the most common genetic events in acute leukemia, and plays an important role for the RB/p16 pathway in the pathogenesis of acute leukemia.

Methods for rapid cloning and detection for sequencing of cloned inverse PCR-generated DNA fragments adjacent to known sequences in bacterial chromosomes

Since the invention of PCR, many adaptation techniques have been developed for sequencing DNA fragments flanking known sequences. Of them, inverse PCR is a matter of interest because of the simplicity of its principle. However, the protocols for inverse PCR introduced so far consist of some time-consuming procedures, and with them, we cannot "walk" chromosomes too far since the number of suitable restriction enzymes is limited. Our experiments led to confirming simpler technical approaches applicable to the case of bacterial chromosomes, that is, designing two end-specific "contextual" sequences with which we can quickly detect the desired clones of targeted DNA fragments by simply analyzing PCR products, employing "the minimum value of the desired fragments" as a "discriminating minimum" value to decrease contaminant DNA fragments, and creating a new tandem of two cleaved end fragments of a known sequence ("reordering") for PCR amplification in combination with cloning of the inverse PCR-generated DNA. With the improvements, we could both simplify the procedures and broaden the capacity of the inverse PCR in "walking" chromosomes.

[Study on the verotoxin-producing Escherichia coli--isolation of the bacteria from deer dung]

To identify the source and route of verotoxin-producing Escherichia coli (VTEC) infection in humans, we tried to isolate VTEC from fresh deer dung collected from free-range animals in two parks during the period from August 1997 to January 1998. The results are presented below. 1) VTEC were isolated from 21 of 200 deer dung samples (10.5%), consisting of 15 of 100 samples (15.0%) collected in park A and 6 of 100 samples (6.0%) collected in park B, suggesting that the incidence of VTEC isolation differs depending on location. 2) With respect to typing of verotoxin, the 21 isolated VTEC strains consisted of 10 strains (47.6%) as VT1 producer, 5 strains (23.8%) as VT2 producer, and 6 strains (28.6%) as double producer of both types. 3) With respect to serogroup of the isolated VTEC strains, 2 strains belonged to O128:H2.1 strain each belonged to the O8:H10, O128:H12, and O169:HUT groups. The remaining 16 strains failed to be identified as particular serotypes. Regarding local distribution of the serotype, in park A, 1 strain each belonged to the O128:H2, O8:H10, and O169:HUT groups. The remaining 12 strains did not clearly show particular serotypes. In park B, 2 strains belonged to O128:H2, and 4 strains failed to show particular serotypes. The remaining 1 strains showed autoagglutination. In conclusion, we isolated VTEC strains from deer that showed types of toxin and serogroups identical to those of human VTEC. Therefore, VTEC found in deer dung could well be a source of VTEC-infectious diseases in humans.

Esophageal varices before and after endoscopic variceal ligation: evaluation using helical CT

The purpose of this study was to demonstrate the utility of helical CT in assessing the therapeutic effects of endoscopic variceal ligation (EVL). Twenty-four patients with esophageal varices were examined. Helical scanning was initiated 60 s after intravenous injection (Iopamidol 300 mgI/ml, total 120 ml, 3 ml/s) was started. Esophageal varices were clearly depicted as high-density areas. Multiplanar reformation and 3D images demonstrated collateral circulation three-dimensionally. After EVL, mucosal high-density areas had diminished markedly, but collateral veins around the esophagus, and gastro- and/or spleno-renal shunts, were unchanged in all patients. Of 21 patients with collateral circulation, esophageal varices recurred endoscopically in 6 patients within 12 months. In 3 patients without collateral circulation, esophageal varices did not recur within 12 months. From these findings, we conclude that helical CT is a useful method for assessing the therapeutic effects of EVL.

Peroxiredoxin I expression in human thyroid tumors

Peroxiredoxin I (Prx I) is newly discovered oxidative stress inducible protein, having a thioredoxin peroxidase activity. The Prx I expression level in 107 samples out of 60 thyroid lesions, including normal thyroid, tumors and thyroiditis including Graves' disease were examined using immunoblotting. Prx I expression levels in follicular neoplasm (P = 0.00005) and thyroiditis group (P = 0.0037) were significantly higher than that of the control group, while papillary carcinoma group did not show statistical significance. Immunohistochemistry indicated that Prx I was in epithelial cells of thyroid follicles. These results suggest that Prx I is expected to be a candidate for novel tumor markers to discriminate tissue types of tumors.

Effect of A1 adenosine receptor agonist upon cochlear dysfunction induced by transient ischemia

The present study was undertaken to determine whether 2-chloro-N6-cyclopentyladenosine (CCPA), a highly selective A1 adenosine receptor agonist, attenuated cochlear dysfunction induced by transient ischemia or not. Ischemia of different durations (15, 30 or 60 min) was induced in 46 albino guinea pigs by transiently pressing the labyrinthine artery. CCPA or physiological saline solution was intraperitoneally administered to the animals 15 min prior to ischemia. The post-ischemic CAP threshold shift from the pre-administration value was measured 4 h after the onset of reperfusion to assess post-ischemic cochlear dysfunction. A statistically significant reduction in the CAP threshold shift was seen in CCPA-given animals after 15- and 30-min ischemia, whereas there was no statistical difference after 60-min ischemia. These results suggest that A1 adenosine receptor agonist exerts a protective effect on the cochlear injury induced by transient ischemia of intermediate duration.

Thallium-201 SPECT of adjacent intracranial tumours: a contrast in thallium kinetics

We report a case of adjacent intracranial tumours: malignant fibrous histiocytoma (MFH) and meningioma. Thallium-201 single-photon emission computed tomography demonstrated different thallium kinetics between the tumours (slow washout from the MFH and rapid clearance in the meningioma) and could be said to have been useful for preoperative histological estimation.