Stromal-type Nephroblastoma with or without Anaplasia in Two Hedgehogs (Atelerix albiventris)

We describe the clinical and histological characteristics of stromal-type nephroblastomas that developed in two hedgehogs (Atelerix albiventris). In case 1, the tumour was composed of a proliferation of anaplastic stromal cells with ductal structures resembling the epithelium of nephroblastoma. In case 2, spindle-shaped cells that were somewhat larger than nephroblasts were frequently seen surrounding the cell cluster, and there was proliferation of stromal cells with collagen fibres at the periphery. Immunohistochemically, the tumour cells labelled weakly to strongly for the nephroblast marker Wilms' tumour-1 and were positive for Ki67 with rates of 5% and 10% for cases 1 and 2, respectively. Based on the above, the diagnosis was of stromal-type nephroblastoma with anaplasia in case 1 and without anaplasia in case 2. Our findings suggest that stromal-type nephroblastomas arise in adult hedgehogs and are clinically benign, and that histological anaplasia does not affect the prognosis.

Expression of CA19-9, SLX, STN and CEA in relatively early gastric carcinoma

Expression and presence of the carbohydrate antigens CA19-9, SLX and STN, and CEA in tissues and serum were examined in 132 patients with early or propria muscle invaded gastric cancer. The seropositive rate was not different in patients with cancer or gastritis. In tumor tissue, the positive rate for these antigens was 28.8% in CA19-9, 9.1% in SLX, 47.0% in STN and 72.9% in CEA. Results showed that gastric cancers, even at an early stage, produce abnormal carbohydrate antigens not detected in normal tissues. However, transfer of antigens into the circulation was not observed in patients with early gastric cancer, suggesting the possibility that number of carcinoma cells may be involved in the transfer of antigens into blood.

Effects of prolonged water washing of tissue samples fixed in formalin on histological staining

The effects of prolonged water washing after fixation for 48 h in 10% (v/v) phosphate-buffered neutral formalin on the quality of representative histological staining methods were evaluated using samples of liver, kidney, spleen and thymus collected from three male Crl:CD(SD)(IGS) rats and one male beagle dog. Because door-to-door courier services in Japan prohibit handling formalin, our goal was to confirm that formalin fixed wet tissue samples could be stored in tap water rather than formalin during transportation of the samples without decreasing the quality of their staining or immunohistochemistry. Each tissue sample was allocated randomly to one of three groups: 12 min, 3 days and 7 days of washing in running tap water; samples then were routinely embedded in paraffin and sectioned. The sections were stained with hematoxylin and eosin, perio-dic acid-Schiff, azan, and the TdT-mediated dUTP-biotin nick end labeling (TUNEL) method. Immunohistochemical staining for Factor VIII, ED-1 and CD3 also was assessed. Prolonged water washing for up to 7 days did not affect the morphology or stainability by standard histological methods, or the intensity and frequency of positive reactions using the TUNEL method. Only immunohistochemical staining of Factor VIII was altered in both the rat and dog sections after 7 days of water washing. The intensity of positive reactions of Factor VIII immunohistochemistry after 7 days water washing was still strong enough to detect microscopically. Therefore, prolonged water washing for up to 7 days after formalin fixation does not have seriously detrimental effects on the quality and characteristics of paraffin sections stained by various methods, including immunohistochemistry.

Influence of hypobaric hypoxia on bispectral index and spectral entropy in volunteers

BACKGROUND

Hypoxia has been shown to change electroencephalogram parameters including frequency and amplitude, and may thus change bispectral index (BIS) and spectral entropy values. If hypoxia per se changes BIS and spectral entropy values, BIS and spectral entropy values may not correctly reflect the depth of anaesthesia during hypoxia. The aim of this study was to examine the changes in BIS and spectral entropy values during hypobaric hypoxia in volunteers.

METHODS

The study was conducted in a high-altitude chamber with 11 volunteers. After the subjects breathed 100% oxygen for 15 min at the ground level, the simulated altitude increased gradually to the 7620 m (25,000 ft) level while the subjects continued to breathe oxygen. Then, the subjects discontinued to breath oxygen and breathed room air at the 7620 m level for up to 5 min until they requested to stop hypoxic exposure. Oxygen saturation (SpO2), heart rate, 95% spectral edge frequency (SEF), BIS, response entropy (RE), and state entropy (SE) of spectral entropy were recorded throughout the study period.

RESULTS

Of the 11 subjects, seven subjects who underwent hypoxic exposure for 4 min were analysed. SpO2 decreased to 69% at the 7620 m level without oxygen. However, SEF, BIS, RE, and SE before and during hypoxic exposure were almost identical.

CONCLUSION

These data suggest that hypoxia of oxygen saturation around 70% does not have a strong effect on BIS and spectral entropy.

Usefulness and faults of the sentinel lymph node biopsy using dye technique in distal gastrectomy for gastric cancer

e15509

Background: We apply sentinel node biopsy (SNB) in distal gastrectomy to perform it as safe limited surgery. Limited surgery is a procedure in which the extent of lesion resection and lymph node dissection is reduced. We assessed usefulness and faults of intraoperative diagnosis of lymph node metastasis in this regard. Methods: Surgical procedures: Patent blue (1%) is injected submucosally into 4 to 5 different sites at 1 mL per site around the primary tumor. If blue nodes are found, biopsy and diagnosis of metastasis are performed at this point. Subjects and methods: The study was conducted in 96 gastric cancer patients with a preoperative diagnosis of T1 or mp invasion. Informed consent was obtained from the all patients. There were 65 males and 31 females with a mean age of 64.2 years. Tumor invasion of m, sm, mp, ss, and se was identified in 44, 38, 8, 2, and 4 patients, respectively. All patients underwent open distal gastrectomy (DG) (n=31) or laparoscopy-assisted distal gastrectomy (LADG) (n=65) and Billroth-I reconstruction. Results: The mean number of BNs dissected was 4.5 and 3.7 in DG and LADG cases, respectively. Intraoperative identification and biopsy of BNs could be performed in 34 of 35 DG patients and in 58 of 61 LADG patients. Of the 34 patients in whom BNs were identified, 5 had metastases in BNs confirmed by intraoperative frozen section diagnosis in DG cases. On the other hand, of the 58 LADG patients in whom BNs were identified, 5 had metastases in BNs confirmed by intraoperative frozen section diagnosis in LADG case. False-negative rate was 1.9%. Conclusions: SNB can be performed in LADG as well as in DG. For the case that shows infiltration up to MP, the possibility of lymph node metastasis for other lymph node is considered to be negligible. In obese cases we had some cases of no BNs and false-negative. In consequence, as long as the infiltration is lower than MP, and confirmed that metastasis was not found by blue node biopsy, distal gastrectomy using limited surgery would be thought to be done safely.

No significant financial relationships to disclose.

Overexpression of EphA4 gene and reduced expression of EphB2 gene: Correlation with liver metastasis in colorectal cancer

e15129

The Eph receptors, members of a large family of transmembrane receptor tyrosine kinases, play important roles in a variety of biologic functions. Recent studies have suggested that EphA4 and EphB2 participate in the growth and development of various carcinomas. This study examined the relations of EphA4 and EphB2 gene expression to clinicopathological factors, especially metastasis, in patients with colorectal cancer. We studied surgical specimens of cancer tissue and adjacent normal mucosa obtained from 205 patients with untreated colorectal cancer. The relative expression levels of EphA4 and EphB2 mRNA in the specimens were measured by quantitative real-time, reverse-transcription polymerase chain reaction. The relative expression level of EphA4 mRNA was higher in the presence than in the absence of liver metastasis, whereas the relative expression levels of EphB2 mRNA were similar. Analysis of the relations between clinicopathological features and gene expression showed that high expression of the EphA4 gene and low expression of the EphB2 gene correlated with liver metastasis. There was no correlation between EphA4 and EphB2 gene expression. Our results suggest that over-expression of the EphA4 gene and reduced expression of the EphB2 gene might promote liver metastasis in colorectal cancer. Over-expression of the EphA4 gene and reduced expression of the EphB2 gene may thus be a useful predictor of liver metastasis in patients with colorectal cancer.

No significant financial relationships to disclose.

Reduction therapy of ALT levels and prevention of HCC development in patients with HCV-associated cirrhosis

1529

Background: Approximately 30 million people worldwide are estimated to have liver cirrhosis (LC) associated with hepatitis C virus (HCV). In addition, patients with HCV-associated liver cirrhosis (HCV-LC) have a high risk of developing hepatocellular carcinoma (HCC). Namely, 60–80% of the patients may develop HCC in 10 years. So, preventing these patients from developing HCC is an urgent problem to be solved. To find a way to prevent the development of hepatocellular carcinoma (HCC) from hepatitis C-virus associated liver cirrhosis (HCV-LC), an analysis of the HCV-LC patients who had reduction therapy of ALT levels was performed. Patients and Methods: Seventy-four consecutive HCV-LC patients of Child Stage A were followed for > 10 years for the development of HCC. They were divided into two groups: In group A, the reduction therapy for ALT levels is aggressively performed and in group B, the reduction therapy was not performed aggressively. Results: Initial ALT was higher in group A than in group B, but there was no significance. After reduction therapy, ALT level was significantly high in group A in the first year. However, there were no significant differences between ALT levels in groups A and B of after the second year. In total, 39 patients out of 74 (52.7%) developed HCC within 13 years from the beginning of the study and 35 patients did not developed HCC in the same observation period. The incidence of HCC development in group B [65.7% (23/35)] was significantly higher than in group A [41.0% (16/39)] (p=0.039). The median HCC developing time in group A (12.8 years) was significantly longer than in group B (3.8 years) (p=0.0013). Multivariate analysis demonstrated that reduction therapy and ALT levels were the significant factors affecting HCC development. The incidence of HCC development in group B was 5.8 times higher than in group A. The high and unclassified ALT groups were 4.6 times and 2.2 times higher than in the low ALT group. Conclusion: The chances of surviving for more than 10 years without developing HCC in the HCV-LC patients of Child Stage A were far more favorable in group A than in group B. These results suggest that aggressive reduction therapy for ALT levels in HCV-LC patients could significantly prevent HCC development.

No significant financial relationships to disclose.

Phase II study of S-1 as a first-line, S-1 plus cisplatin as a second-line, and weekly paclitaxel as a third-line therapy in patients with advanced gastric carcinoma

15186

Background: We conducted a pilot phase II study to evaluate the efficacy and safety of S-1 as a First-line, S-1 plus cisplatin as a second-line, and weekly paclitaxel as a third-line therapy for advanced gastric cancer. Patients and Methods: Between 2002 and 2005, 19 patients were enrolled into this study. Chemotherapy consisted of 60 mg/m2 of S-1 for 4 weeks at 6 weeks interval, 60 mg/m2 of S-1 for 3 weeks and 60mg/m2 Cisplatin on day 8 at 5 weeks interval, and paclitaxel 60 mg/m2 day 1, 8, 15 at 4 weeks interval. Results: The response rate was 15.8%, 7.7%, and 0% in the first-, second-, and third-line, respectively. The time to progression was 314 days. The mean survival time was 994 days. The median survival time was not calculated because 12 patients are still alive. With respect to hematological toxicity, the major adverse effect was leukopenia, which reached grades 3–4 in all line. And non-hematological toxicities, the major adverse effect was anorexia, which reached grade 3–4 in the Second line, and no deaths were attributable to the adverse effects of the drugs. Conclusion: This sequential therapy was very effective treatment for advanced gastric cancer with acceptable toxic side-effects.

No significant financial relationships to disclose.

Partial protection against challenge with the highly pathogenic H5N1 influenza virus isolated in Japan in chickens infected with the H9N2 influenza virus

The protective effect of the A/Ck/Yoko/aq55/01 (H9N2) avian influenza virus against the highly pathogenic H5N1 virus, i.e., A/Ck/Yama/7/04 (genotype V), was examined. Three 5-week-old chickens were inoculated intranasally with the H9N2 virus (10(8.6) EID(50)/head) and were kept with two contact chickens. All of the infected chickens were reinoculated with the same virus at 20 weeks of age, and 10 days later, they were challenged intranasally with the H5N1 virus (10(4.0) EID(50)/head). Five chickens simultaneously challenged with only the H5N1 virus (challenge control) died within 4 days postchallenge (d.p.c.). In contrast, four out of the five challenged, immune chickens died from 5 to 8 d.p.c. The median time to death in the immune chickens (6.3 days) was significantly longer than that in the challenge controls (3.4 days) (P < 0.01). No H5N1 virus shedding into the tracheae and feces of the challenged, immune chickens were detected for 3 d.p.c., but H5 genes were detectable in only one chicken by a loop-mediated isothermal amplification method. The H5N1 viruses were detected in the tracheae and/or feces of the dead immune chickens at death or 1 to 2 days before death. Only one out of the five challenged, immune chickens survived the H5N1 challenge without any signs for 14 d.p.c., but the virus and H5 gene were sporadically detected in the trachea only 7 and 14 d.p.c., respectively. This study shows that the H9N2 viruses may have the potential to induce cross-protection to the challenge with a recent lethal H5N1 virus (genotype V).

Impact of Different Husbandry Conditions on Contact and Airborne Transmission of H5N1 Highly Pathogenic Avian Influenza Virus to Chickens

Typically highly pathogenic avian influenza (HPAI) viruses spread very rapidly among chickens within sheds. However, the spread was slower than expected for the initial 10 days of the index farm in Japan during 2004. This slow spread, as well as the lack of gross lesions, clinical signs, or high mortality, hindered the field veterinarian from reporting a suspected HPAI outbreak to the veterinary office. To understand the field conditions for the slow virus spread, we examined contact and airborne transmission of the H5N1 virus to chickens in a negative-pressure isolator using various numbers of infected chickens and separate compartments. We found that the contact transmission did occur inefficiently when one or two chickens were infected, whereas the transmission was efficient when four chickens were infected. Airborne transmission of the HPAI virus was also dependent on the number of infected chickens and was less efficient than contact transmission. These data together with field observations suggested that number of infected chickens, chicken house types, and amount of environmental contamination might affect the virus transmission efficiency to chickens.

Technique and assessment of sentinel lymph node biopsy usefulness in laparoscopy-assisted distal gastrectomy

BACKGROUND

Recently, some studies have suggested that sentinel node biopsy also can be applied to gastric cancer. The authors apply sentinel lymph node biopsy in laparoscopy assisted distal gastrectomy to perform it as safe limited surgery. Limited surgery is a procedure in which the extent of lesion resection and lymph node dissection is reduced. The authors demonstrate that intraoperative diagnosis of lymph node metastasis is useful in this respect.

METHODS

The study was conducted with 38 patients (29 men and 9 women) who had a preoperative diagnosis of T1 tumor invasion. The patients had a mean age of 66.2 years. Patent blue (1%) was injected submucosally into four or five different sites around the primary tumor at 1 ml per site. Blue-stained lymphatics and lymph nodes could be seen by turning over the greater omentum and the lesser omentum extraperitoneally. If blue nodes were found, biopsy was performed.

RESULTS

The mean number of blue nodes dissected was 2.5 +/- 1.9. Intraoperative identification and biopsy of blue nodes could be performed for 35 (92.1%) of the 38 patients. Of the 35 patients in whom blue nodes were identified, 4 (9.7%) had metastases in blue nodes confirmed by intraoperative frozen-section diagnosis. Intraoperative frozen-section diagnosis was negative for blue node metastasis in 31 patients. Postoperative permanent section diagnosis also showed no evidence of lymph node metastasis in these 31 patients (100% accuracy, 0% false-negative rates).

CONCLUSION

The reported method allows observation of blue-stained lymphatics up to 2 h after patent blue injection. Sentinel node biopsy was performed in laparoscopy assisted distal gastrectomy, making it technically equivalent to open gastrectomy. Sentinel node biopsy can serve as a method to determine the appropriate use of laparoscopy assisted distal gastrectomy for management of T1 gastric cancer.

Pathology of fatal highly pathogenic H5N1 avian influenza virus infection in large-billed crows (Corvus macrorhynchos) during the 2004 outbreak in Japan

Highly pathogenic H5N1 avian influenza viruses were isolated in 9 large-billed crows that died in Kyoto and Osaka prefectures in Japan from March to April in 2004. We studied 3 of the 9 crows using standard histologic methods, immunohistochemistry, and virus isolation. The most prominent lesions were gross patchy areas of reddish discoloration in the pancreas. The consistent histologic lesions included severe multifocal necrotizing pancreatitis, focal degeneration and necrosis of neuron and glial cells in the central nervous system, and focal degeneration of cardiac myocytes. All of these tissues contained immunohistochemically positive influenza viral antigens. The virus was isolated from the brain, lung, heart, liver, spleen, and kidney of the crows examined. Thus we concluded that highly pathogenic avian influenza virus was associated with clinical disease, severe pathologic changes, and death in the 3 crows.

Distribution of Viral Antigens and Development of Lesions in Chicken Embryos Inoculated with Nipah Virus

An isolate of Nipah virus was injected into fertile eggs via the allantoic cavity or yolk sac. Allantoic inoculation resulted in considerable pathological variation and only partial mortality. Dead embryos showed severe necrosis in the brain and congestion in the kidney and the subcutis of limbs. In contrast, yolk sac inoculation led to uniform infection and mortality, the dead embryos exhibiting the same lesions as those described above but without the subcutaneous congestion. Histological lesions in dead embryos inoculated by either route were similar and particularly severe in the central nervous system. Viral antigens were detected mainly in the vasculature and neurons. The results indicated that Nipah virus is highly pathogenic to chicken embryos, and that the route of inoculation is an important determinant of the course of disease. The findings also suggested that yolk sac inoculation can be used for viral titration, and that the chicken embryo represents a useful model for studying the vascular and neuronal tropisms of Nipah virus.

Use of Microcoil Probehead for Determination of the Structure of Oriented Silk Fibers by Solid-State NMR

A microcoil probehead for solid-state NMR was developed with a two-channel radio-frequency circuit, and 13C observation with a proton-decoupling probehead was performed to obtain information on the distribution of the orientation of silk fibroin molecules in the fiber. The coil (1 mm (diameter) x 5 mm (length)) of the probehead was placed at the angles 90 degrees and 30 degrees , relative to the static magnetic field. Only 70 mug of [1-13C]Gly silk fibroin fiber was used in a magnet of 9.4 T (400 MHz for proton channel).

Effect of sodium valproate on neuromagnetic responses to chromatic flicker: implication for photosensitivity

The effect of oral administration of sodium valproate in normal subjects was evaluated using whole-scalp magnetoencephalography, with results compared to the effect of sodium valproate in photosensitive children. Neuromagnetic responses to 10 Hz equiluminant red-green and red-blue flicker were measured before and after 5 days of sodium valproate administration. For the red-green flicker, relative power spectra at the stimulus frequency (10 Hz) were attenuated with medication in most brain regions. However, for the red-blue flicker, the 10-Hz power in the occipital region was enhanced with medication, while it was reduced in other regions. These results qualitatively resembled those in photosensitive children. The present findings suggest that (1) combinational chromatic sensitivity can be a critical factor for cortical excitability, that (2) the effect of sodium valproate is qualitatively similar in normal and photosensitive subjects, and that (3) the effect of sodium valproate on cortical excitability is not simply to suppress the stimulus-synchronized occipital activity, but rather to inhibit the spread of cortical activity from the occipital region to other regions.

Monoclonal Antibody-based Immunohistochemical Diagnosis of Malaysian Nipah Virus Infection in Pigs

Formalin-fixed, paraffin wax-embedded tissues of three Malaysian farm pigs naturally infected with Nipah virus were used to investigate the value of anti-Nipah virus mouse monoclonal antibodies (Mabs) and rabbit polyclonal antibody for immunohistochemical diagnosis. Mabs 11F6 and 12A5 gave intense immunolabelling in lung tissue that had been fixed in 10% neutral buffered formalin for about 4 years, whereas the reactivity of Mabs 13A5 and 18C4 and polyclonal antibody was reduced significantly by long-term formalin fixation. Immunohistochemical examination of Malaysian farm pig samples with Mab 11F6 confirmed the affinity of Nipah virus for respiratory epithelium, renal glomerular and tubular epithelium, meningeal arachnoidal cells, and systemic vascular endothelium and smooth muscle. In addition, Nipah virus antigens were identified in laryngeal epithelial cells, Schwann cells of peripheral nerve fascicles in the spleen, and endothelial cells in the atrioventricular valve. The study demonstrated the value of Mabs 11F6 and 12A5 for the immunohistochemical diagnosis of Nipah virus infection in pigs.

[Clinical outcome of the operation using deep hypothermic cardiopulmonary bypass with intervals of circulatory arrest in thoracoabdominal aortic aneurysm]

Deep hypothermic cardiopulmonary bypass with intervals of circulatory arrest has been used for protection of the spinal cord during operations for thoracoabdominal aortic aneurysm (TAAA) in our hospital. We examined the effect of this adjunct this time. We studied 15 patients who were operated using deep hypothermic cardiopulmonary bypass with intervals of circulatory arrest among 19 patients with the TAAA who we performed the operations from 1995 through 2003. The patients ranged in age from 21 to 80 (an average of 65 +/- 14 SD) years. We used deep hypothermic cardiopulmonary bypass with intervals of circulatory arrest between 16 and 20 degrees C for the adjunct but did not use a monitor of evoked spinal cord potentials or cerebrospinal fluid drainage. Operation time was an average of 805 +/- 168 minutes. Cardiopulmonary bypass time was an average of 403 +/- 73 minutes. Deep hypothermic cardiopulmonary bypass time was an average of 215 +/- 67.5 SD minutes. Duration of spinal cord ischemia to the intercostal arteries were reconstructed was from 25 to 104 (50.5 +/- 24) minutes. We recognized nerve disorder in 6 cases in progress after operation, and respiratory organs management period and a hospitalization period became long, but the hospitalization death was 3 cases, and, as for the paraplegia was no case, 12 patients were discharged in good condition. The deep hypothermic cardiopulmonary bypass with intervals of circulatory arrest was regarded as a useful adjunct for prevention of the paraplegia.

Staple line coverage with absorbable mesh after thoracoscopic bullectomy for spontaneous pneumothorax

BACKGROUND

Thoracoscopic simple bullectomy for primary spontaneous pneumothorax (PSP) has a relatively high postoperative recurrence rate and sometimes results in postoperative air leakage. One of the reasons for postoperative recurrence is the regrowth of bullae around the staple line. Therefore, reinforcement of the visceral pleura around the staple line is a reasonable way to prevent postoperative air leaks and recurrence. This study was done to determine the efficacy in preventing postoperative air leak and recurrent pneumothorax of widely covering the staple line with absorbable mesh after thoracoscopic bullectomy.

METHODS

Wide coverage of the staple line with absorbable mesh was performed on 114 patients with PSP. These patients were retrospectively compared with 126 patients who underwent thoracoscopic simple bullectomy alone.

RESULTS

The postoperative duration of chest drainage in the coverage group (mean, 1 day; range, 0-5) was significantly shorter than that in the simple bullectomy group (mean, 3 days; range 0-20). A prolonged air leak (>7 days) occurred in six patients in the simple bullectomy group, but there were no such leaks in the coverage group. Recurrent pneumothorax occurred in three patients (2.6%) in the coverage group and 12 patients (9.5%) in the simple bullectomy group.

CONCLUSION

Wide coverage of the staple line with absorbable mesh is effective in preventing postoperative air leak and in decreasing the recurrence rates of PSP.

Complete, long-lasting protection against lethal infectious bursal disease virus challenge by a single vaccination with an avian herpesvirus vector expressing VP2 antigens

Marek's disease herpesvirus is a vaccine vector of great promise for chickens; however, complete protection against foreign infectious diseases has not been achieved. In this study, two herpesvirus of turkey recombinants (rHVTs) expressing large amounts of infectious bursal disease virus (IBDV) VP2 antigen under the control of a human cytomegalovirus (CMV) promoter or CMV/beta-actin chimera promoter (Pec promoter) (rHVT-cmvVP2 and rHVT-pecVP2) were constructed. rHVT-pecVP2, which expressed the VP2 antigen approximately four times more than did rHVT-cmvVP2 in vitro, induced complete protection against a lethal IBDV challenge in chickens, whereas rHVT-cmvVP2 induced 58% protection. All of the chickens vaccinated with rHVT-pecVP2 had a protective level of antibodies to the VP2 antigen at the time of challenge, whereas only 42 and 67% of chickens vaccinated with rHVT-cmvVP2 or the conventional live IBDV vaccine, respectively, had the antibodies. The antibody level of chickens vaccinated with rHVT-pecVP2 increased for 16 weeks, and the peak antibody level persisted throughout the experiment. The serum antibody titer at 30 weeks of age was about 20 or 65 times higher than that of chickens vaccinated with rHVT-cmvVP2 or the conventional live vaccine, respectively. rHVT-pecVP2, isolated consistently for 30 weeks from the vaccinated chickens, expressed the VP2 antigen after cultivation, and neither nucleotide mutations nor deletion in the VP2 gene was found. These results demonstrate that the amount of VP2 antigen expressed in the HVT vector was correlated with the vaccine efficacy against lethal IBDV challenge, and complete protective immunity that is likely to persist for the life of the chickens was induced.

Pancreatic necrosis and ventricular erosion in adenovirus-associated hydropericardium syndrome of broilers

Seven 19-day-old broiler chickens affected with hydropericardium syndrome (HPS) with pancreatic necrosis and gizzard erosions were investigated pathologically and virologically. Mortality increased after 13 days of age in a flock on a broiler farm. The mortality rate of the flock reached 10% by 19 days of age. Macroscopically, the chickens had hydropericardium (the characteristic gross change of HPS), pinpoint white foci in the pancreas, and ventricular erosions. Histologically, the chickens had multifocal hepatic necrosis with intranuclear inclusions in hepatocytes, a marked increase of macrophages in the spleen and lung, mild epicardial edema, multifocal necrosis of pancreatic acinar cells with intranuclear inclusions, focal necrosis of the ventricular koilin layer, and degeneration of the ventricular glandular epithelium with intranuclear inclusions. Immunohistochemically, intranuclear inclusions in the liver, pancreas, and ventriculi were stained positively against group I avian adenovirus (GIAAV) antigens. Ultrastructurally, 67-nm diameter viral particles were present in intranuclear inclusions. Virologically, serotype 4 of GIAAV was isolated from the liver, heart, and kidney of affected chickens. The pathologic changes of the present cases differ from previous cases of HPS; therefore, the present strain of GIAAV may have different pathogenicity for chickens than the previous virus strain of HPS.

Rat mast cell protease-I enhances immunoglobulin E production by mouse B cells stimulated with interleukin-4

Mast cell chymase plays important roles in inflammation and tissue remodeling. Here we show that mast cell chymase also functions as an enhancer of immunoglobulin production. In the culture of murine spleen cells stimulated with lipopolysaccharide and interleukin-4, purified rat chymase (rat mast cell protease-I; RMCP-I), at physiological concentrations, enhanced immunoglobulin E (IgE) and IgG1 syntheses but not IgG3 synthesis. The enhancement was also evident when spleen cells depleted of T cells and macrophages were employed as responding cells. Enzymatic activity of RMCP-I was required to enhance IgE and IgG1, because two inhibitors for chymotryptic enzymes, chymostatin and Y-40613, a novel chymase inhibitor, suppressed the enhanced immunoglobulin production, and phenylmethylsulphonyl fluoride, an irreversible inhibitor for serine proteases, totally abolished the enhancing effect. Furthermore, a specific inhibitor for Zn2+-dependent metalloproteases, GI 129471, could also completely inhibit the production of IgE and IgG1 that was enhanced by RMCP-I, suggesting that a metalloprotease also played an essential role in the immunoglobulin production. Our results together with others show that proteases from mast cell granules have important function not only in the efferent phase but also in the afferent phase of immune responses.

Role of nitric oxide in human gastric cancer cells treated with 5-fluorouracil

We examined whether 5-fluorouracil (5-FU) induces nitric oxide (NO) production and evaluated the role of NO in antitumor activity in human gastric cancer cells. MKN-1 gastric cancer cells were treated with the IC50 of 5-FU in the presence of interferon-gamma (IFN-gamma). In addition, s-methylisothiourea (an antagonist of inducible nitric oxide synthase) or anti-TNF-alpha antibody was added to the culture medium. Production of NO was measured by nitrite assay, TNF-alpha was measured by enzyme-linked immunoabsorbent assay, antitumor activity was evaluated by 3-[4,5-dimethylethiazol-2-yl]-2,5-dipheniltetrasolium bromide (MTT) assay. After 5-FU treatment in the presence of IFN-gamma, NO and TNF-alpha were produced and anti-tumor activity was enhanced. In contrast, s-methylisothiourea abolished the antitumor activity of 5-FU treatment. Anti-TNF-alpha antibody inhibited NO production and decreased the antitumor activity. 5-FU induces NO production by gastric cancer cells, and NO participates in antitumor activity in gastric cancer cells. These effects may be mediated by TNF-alpha production.

Gizzard nematodiasis in Japanese mountain hawk eagle (Spizaetus nipalensis)

In this paper, we report spontaneous gizzard nematodiasis in an adult Japanese mountain hawk eagle (Spizaetus nipalensis). Grossly, the gizzard had a black mucoid substance attached to the surface mucous membrane, and the heart was dilated. Histologically, immature larvae with yellow pigments invaded crypts of the mucous membrane. More developed larvae invaded the lamina propria and muscular layers and serosa of the gizzard, with pressure atrophy and cellular reaction (infiltration of heterophils and macrophages and proliferation of fibrous connective tissue). Moderate bronchopneumonia due to larvae invasion was also seen in the lung. The morphology suggests that the parasites may be nematodes, but the species of nematode could not be confirmed. The bird may have died from malabsorption and respiratory damage as a result of the gizzard and lung lesions.

Identification of a genetic determinant of pathogenicity in chicken anaemia virus

The molecular basis of pathogenicity of the chicken anaemia virus (CAV) needs to be clarified in order to develop a safe, live virus vaccine. In this study, several high- and low-pathogenic infectious DNA clones were obtained from field virus samples after 12 or 38 passages in MDCC-MSB1 cells. The high-pathogenic clones induced a low haematocrit, low weight gain and high mortality. Nucleotide sequence analyses identified one amino acid, at residue 394 of the VP1 capsid protein, as a major determinant of pathogenicity. To determine the role of this amino acid in pathogenicity, chimeric infectious DNA clones and point-mutated clones were used for chicken pathogenicity tests. These analyses clearly demonstrated that residue 394 of VP1 was crucial for the pathogenicity of CAV; all of the cloned viruses with glutamine at this position were highly pathogenic, whereas those with histidine had low pathogenicity. Low-pathogenic CAV, based on an infectious DNA clone, is a candidate for a genetically homogeneous and stable CAV live vaccine.

Synthesis, structure-activity relationships, and pharmacokinetic profiles of nonpeptidic alpha-keto heterocycles as novel inhibitors of human chymase

We designed nonpeptidic chymase inhibitors based on the structure of a peptidic compound (1) and demonstrated that the combination of a pyrimidinone skeleton as a P3-P2 scaffold and heterocycles as P1 carbonyl-activating groups can function as a nonpeptidic chymase inhibitor. In particular, introduction of heterobicycles such as benzoxazole resulted in more potent chymase-inhibitory activity. Detailed structure-activity relationship studies on the benzoxazole moiety and substituents at the 2-position of the pyrimidinone ring revealed that 2r (Y-40079) had the most potent chymase-inhibitory activity (K(i) = 4.85 nM). This compound was also effective toward chymases of nonhuman origin and showed good selectivity for chymases over other proteases. Pharmacokinetic studies in rats indicated that 2r was absorbed slowly after oral administration and showed satisfactory bioavailability (BA) (T(max) = 6.0 +/- 2.3 h, BA = 19.3 +/- 6.6%, t(1/2) = 35.7 +/- 13.3 h). In conclusion, 2r is a novel, potent, and orally active chymase inhibitor which would be a useful tool in elucidating the pathophysiological roles of chymase.

Synthesis, structure-activity relationships, and pharmacokinetic profiles of nonpeptidic difluoromethylene ketones as novel inhibitors of human chymase

Potent human chymase inhibitors with high enzymatic selectivity and satisfactory metabolic stability were obtained by replacing the Val-Pro (P3-P2) dipeptide portion of the previously described inhibitor 1 with a nonpeptidic pyrimidinone skeleton. The potency of the novel compounds was further enhanced by the introduction of carbamoyl-substituted difluoromethylene ketone moieties. The most potent chymase inhibitor of the newly created series was 2u (Y-40018), which had a K(i) of 2.62 nM. Compound 2u possessed high selectivity for human chymase since it lacked significant activity toward other representative human proteolytic enzymes. Moreover its strict specificity for human chymase suggested that 2u strongly inhibited human and canine chymases but not rat and mouse ones. Pharmacokinetic studies in rats and dogs indicated that 2u was absorbed rapidly after oral administration and had satisfactory bioavailability in these experimental animal species (rat, 17%; dog, 32%). In conclusion, 2u is a novel, potent, and orally active chymase inhibitor which would prove very useful in revealing the precise roles of the latter in various pathophysiological processes.

Imported parakeets harbor H9N2 influenza A viruses that are genetically closely related to those transmitted to humans in Hong Kong

In 1997 and 1998, H9N2 influenza A viruses were isolated from the respiratory organs of Indian ring-necked parakeets (Psittacula Krameri manillensis) that had been imported from Pakistan to Japan. The two isolates were closely related to each other (>99% as determined by nucleotide analysis of eight RNA segments), indicating that H9N2 viruses of the same lineage were maintained in these birds for at least 1 year. The hemagglutinins and neuraminidases of both isolates showed >97% nucleotide identity with those of H9N2 viruses isolated from humans in Hong Kong in 1999, while the six genes encoding internal proteins were >99% identical to the corresponding genes of H5N1 viruses recovered during the 1997 outbreak in Hong Kong. These results suggest that the H9N2 parakeet viruses originating in Pakistan share an immediate ancestor with the H9N2 human viruses. Thus, influenza A viruses with the potential to be transmitted directly to humans may be circulating in captive birds worldwide.

Non-peptidic inhibitors of human chymase. Synthesis, structure-activity relationships, and pharmacokinetic profiles of a series of 5-amino-6-oxo-1,6-dihydropyrimidine-containing trifluoromethyl ketones

Chymase possesses a wide variety of actions, including promotion of angiotensin II production and histamine release from mast cells. However, due to a lack of effective inhibitors featuring both high inhibitory activity and high metabolic stability, the pathophysiological role of chymase has not been fully elucidated. We designed non-peptidic inhibitors based on the predicted binding mode of the peptidic chymase inhibitor Val-Pro-Phe-CF3 and demonstrated that the Val-Pro unit is replaceable with a (5-amino-6-oxo-2-phenyl-1,6-dihydro-1-pyrimidinyl)acetyl moiety. Structure-activity relationship studies revealed that phenyl substitution at the 2-position of the pyrimidinone ring is indispensable for high activity. The most potent compound 1h (Ki = 0.0506 microM) is superior in potency to the parent peptidic inhibitor Val-Pro-Phe-CF3 and has good selectivity for chymase over other proteases. The related analogue 1e was orally absorbed and maintained high plasma levels for at least 2h. These results suggest that the derivatives reported here could be developed as agents for treatment of chymase-induced disease.

Laparoscopic surgery using a newly designed suction lifter

The authors describe a simple and available abdominal wall-lift technique for endoscopic surgery that involves a new suction lifter that they designed for laparoscopic surgery. Since July 1998, the authors have used this technique successfully in eight patients with appendicitis, in one patient with a perforated duodenal ulcer, and in one patient with an adenoma of the ascending colon.

Angiogenesis in hepatocellular carcinoma as evaluated by alpha smooth muscle actin immunohistochemistry

BACKGROUND/AIMS

Angiogenesis has been known to be associated with tumor development. In this study, neovascularization in small hepatocellular carcinoma was investigated by evaluation of intratumoral arteriole counts, using alpha smooth muscle actin antibody immunohistochemistry.

METHODOLOGY

Surgical specimens from 38 patients with small hepatocellular carcinoma were immunostained for alpha smooth muscle actin and proliferating cell nuclear antigen. The correlation between intratumoral arteriole density and clinicopathological factors including angiographic findings, proliferative activity, and patient prognosis were analyzed.

RESULTS

Significant difference in intratumoral arteriole density were observed between well-differentiated hepatocellular carcinoma and poorly differentiated hepatocellular carcinoma (P = 0.004) or moderately differentiated hepatocellular carcinoma and poorly differentiated hepatocellular carcinoma (P = 0.011). The mean intratumoral arteriole count in the tumors showing angiographic hypervascularity was significantly higher than that in the tumors without angiographic hypervascularity (P = 0.011). A significant and positive correlation was found between proliferating cell nuclear antigen labeling index and intratumoral arteriole density (r = 0.5232, P = 0.001). A high intratumoral arteriole density in tumor was significantly correlated with shorter patients survival (P = 0.018). Cox's multivariate regression analysis showed that the intratumoral arteriole density was independent prognostic factors (P = 0.0306).

CONCLUSIONS

Intratumoral arteriole density was found to be significantly associated with histological grade, proliferative activity, and patient survival. It also reflected the angiographic findings. Alpha smooth muscle actin antibody immunohistochemistry would provide a simple and biologically significant method which is usable to screen neovascularization and arterial blood supply in hepatocellular carcinoma, and may have predicting utility for patients outcome. This technique is applicable to routine paraffin sections, and may be useful as an adjunct to surgical pathology of hepatocellular carcinoma.