Intraperitoneal hyperthermic perfusion combined with surgery effective for gastric cancer patients with peritoneal seeding

Fifteen patients with far-advanced gastric cancer were given surgical treatment followed by intraperitoneal hyperthermic perfusion (IPHP) with mitomycin C (MMC) and misonidazole (MIS), a thermosensitizing drug. Immediately after extensive resection of the abdominal tumors, a 2-hour IPHP was performed at the inflow temperature of 44.7 to 48.7 C, using equipment designed for treatment of cancerous peritoneal seeding as a closed circuit, and under hypothermic general anesthesia at 30 to 31 C. In nine of the 15 patients with peritoneal seeding and/or ascites, cancerous ascites was absent after this treatment. In all cases, repeated cytologic examinations of the lavage from Douglas's pouch were negative. The postoperative courses were uneventful except for Patients 1 and 10, in whom slight leakage occurred. All patients were discharged and are in good health at the time of this writing, 7.2 +/- 4.6 months after the treatment. The Case 4 Patient recently died in a traffic accident. In all patients, transient hepatic dysfunction and hypoproteinemia occurred after the operation. This extensive surgery combined with IPHP using MMC and MIS was well tolerated and is a safe antitumor treatment for gastric cancer with peritoneal dissemination. Neurotoxicity due to MIS was nil.

A porcine homolog of the major secretory protein of human epididymis, HE1, specifically binds cholesterol

A porcine homolog of the major secretory protein of human epididymis, HE1, was for the first time purified from the porcine cauda epididymal fluid. The HE1 homolog was secreted into the epididymal fluid as a 19-kDa glycoprotein, whose sugar moiety was gradually processed to form a 16-kDa protein during transit through the epididymis. The HE1 homolog mRNA was detected only in the caput and corpus epididymis among the porcine tissues examined. The purified HE1 homolog specifically bound cholesterol with high affinity (Kd=2. 3 microM). The binding stoichiometry was determined to be 0.94 mol/mol, suggesting that 1 mol of cholesterol binds to 1 mol of the protein. It was also found that the HE1 homolog is a major cholesterol-binding protein in the porcine epididymal fluid. The possibility that the HE1 homolog is involved in the regulation of the lipid composition of the sperm membranes during the maturation in epididymis is discussed.

Positive results of combined therapy of surgery and intraperitoneal hyperthermic perfusion for far-advanced gastric cancer

To evaluate the clinical efficacy of intraperitoneal hyperthermic perfusion (IPHP) for far-advanced gastric cancer, particularly with peritoneal seeding, we investigated the survival times of 59 patients who underwent distal subtotal gastrectomy, total gastrectomy, or total gastrectomy combined with concomitant resection of some of the remaining intra-abdominal organs. In all the 30 patients given IPHP, no cancer cells were present posthyperthermically in the lavage from the Douglas pouch. The 30 patients given IPHP lived longer than the 29 patients not given IPHP (p = 0.001), with a 1-year survival rate of 80.4% in the former group compared to 34.2% in the latter. With respect to a comparison of survival time of patients with peritoneal seeding, 7 patients not given IPHP had a 6-month survival rate of 57.1% and did not survive more than 9 months, whereas 20 patients given IPHP had 1- and 2-year survival rates of 78.7% and 45.0%, respectively; here the difference was significant (p = 0.001). The IPHP and control groups without peritoneal metastasis included 10 and 22 patients, respectively, and the 1-year survival rates are 85.4% and 45.3%, respectively. The survival rates of the former exceeded those of the latter, with p = 0.015 by the generalized Wilcoxon test. Thus this combined therapy offers the promise of extended survival for patients with far-advanced gastric cancer.

Clinical trial with surgery and intraperitoneal hyperthermic perfusion for peritoneal recurrence of gastrointestinal cancer

To treat six patients with peritoneal recurrence after radical operation for gastrointestinal cancer, an intraperitoneal hyperthermic perfusion (IPHP), combined with surgical resection of recurrent tumors, intestinal by-pass anastomosis, or both, was carried out. Immediately after complete resection of the intraperitoneal recurrent tumors, a 2- to 3-hour IPHP was performed under hypothermic general anesthesia at about 32 degrees C, using a perfusate containing 10 micrograms/ml or 20 micrograms/ml of mitomycin C (MMC) warmed at the inflow temperature of 46.6 degrees C to 46.9 degrees C. The apparatus used for IPHP was designed for intraperitoneal perfusion as a closed circuit. Although five of the six patients had a malignant peritoneal effusion at the time of admission, the effusion disappeared soon after IPHP, and no cancer cell was present in the lavage from Douglas' pouch. The other patient had a recurrent tumor at the anastomotic region after low anterior resection for rectal cancer and complete resection of the recurrent tumor, combined with IPHP, was carried out. One patient with a recurrent gastric cancer died of hepatic metastasis and cancerous pleuritis 5 months after this treatment, and the other five are in good health 12.8 +/- 5.1 months after IPHP. On the other hand, five patients with intra-abdominal recurrent gastric cancer, who received only surgical treatment within the same period of time, died 3.0 +/- 2.1 months after the surgery. Postoperatively, in the six patients with IPHP, transitory hepatic dysfunction, hypoproteinemia, and thrombocytopenia occurred. These results show that IPHP using MMC combined with surgery is a safe, reliable treatment for patients with peritoneal recurrence of gastrointestinal cancer.

Genomic structure of swine taste receptor family 1 member 3, TAS1R3, and its expression in tissues

Taste receptor family 1 member 3, TAS1R3, is shown to be involved in sweet and umami tastes in mouse, and the nucleotide sequence of the gene has been reported in rat, gorilla, and human. Pigs are frequently used as models for human diseases, and are also considered to be source animals for xenotransplantation to humans due to their anatomical and physiological similarities to humans. Therefore, in the present study, the genomic structure of the swine TAS1R3 gene was determined, and TAS1R3 expression was studied in various swine tissues. The gene was shown to reside on swine chromosome 6q22-->q23, from which three types of mRNAs were generated: 3,752 bp derived from six exons in tongue, 3,704 bp from six exons and 3,630 bp from seven exons in testis. The 6 exons/5 introns were structurally similar to those of humans and mice, but the 7 exons/6 introns structure of TAS1R3 was first observed in swine. High expressions of TAS1R3 were revealed in tongue, kidney, and testis by real-time PCR. The expression profile of the tissues except for kidney was similar to that of mouse. When in situ hybridization using an RNA probe for TAS1R3 was performed on swine tongue and testis tissues, TAS1R3 expressions were revealed in tongue circumvallate papillae, fungiform papillae, mucosal epithelium, follicular B lymphocytes, lymphocytes in submucosal tissues of lingual tonsil, and spermatogenic cells. Using peripheral mature B lymphocytes, the expression of TAS1R3 in B lymphocytes was further confirmed by real-time PCR and sequencing of the real-time PCR product.

Stapled or manual suturing in esophagojejunostomy after total gastrectomy: a comparison of outcome in 379 patients

From January 1983 to December 1989, we performed esophagojejunostomy on 379 patients who underwent total gastrectomy for gastric cancer. A mechanical EEA stapler or conventional manual suturing was used. The clinical outcomes of 199 patients in whom stapling was used (stapler group) and 180 patients in whom manual suturing was done (manual group) were compared. Two of the 199 patients in the stapler group and 3 of the 180 patients in the manual group died of causes directly related to the anastomosis. In the stapler group, 16 stapled anastomoses were formed supradiaphragmatically, and manual suturing was done for 6 patients. The highly placed anastomosis was formed without left thoracotomy or with median sternotomy in 8 of the 16 patients in whom the stapling device was used and in 1 of the 6 patients in whom manual suturing was used. The incidence of anastomotic leakage and stenosis did not differ between the groups. Thus, the mechanical stapler facilitated the construction of a rapid, reliable esophagojejunostomic anastomosis.

Oral Status and Dementia Onset: Mediation of Nutritional and Social Factors

Some modifiable risk factors for dementia are closely related to oral health. Although eating and speaking abilities are fundamental oral functions, limited studies have focused on the effect of malnutrition and lack of social interaction between oral health and dementia. We investigated the mediating effects of nutritional and social factors on the association between the number of teeth and the incidence of dementia. This 6-y cohort study used data from the Japan Gerontological Evaluation Study targeting older adults aged 65 y and above. The number of teeth (exposure) and covariates in 2010 (baseline survey), mediators (weight loss, vegetable and fruit intake, homeboundness, social network) in 2013, and the onset of dementia (outcome) between 2013 and 2016 were obtained. The Karlson-Holm-Breen mediation method was applied. A total of 35,744 participants were included (54.0% women). The mean age at baseline was 73.1 ± 5.5 y for men and 73.2 ± 5.5 y for women. A total of 1,776 participants (5.0%) had dementia during the follow-up period. There was a significant total effect of the number of teeth on the onset of dementia (hazard ratio, 1.14; 95% CI, 1.01-1.28). Controlling for nutritional and social mediators, the effect of the number of teeth was reduced to 1.10 (95% CI, 0.98-1.25), leaving an indirect effect of 1.03 (95% CI, 1.02-1.04). In the sex-stratified analysis, the proportion mediated by weight loss was 6.35% for men and 4.07% for women. The proportions mediated by vegetable and fruit intake and homeboundness were 4.44% and 4.83% for men and 8.45% and 0.93% for women, respectively. Furthermore, the proportion mediated by social networks was 13.79% for men and 4.00% for women. Tooth loss was associated with the onset of dementia. Nutritional and social factors partially mediated this association.

Pulse Pressure and Upstroke Time Are Useful Parameters for the Diagnosis of Peripheral Artery Disease in Patients With Normal Ankle Brachial Index

Background

Some peripheral artery disease (PAD) patients have normal ankle brachial index (ABI) (0.9 - 1.4), although ABI is a useful parameter for the diagnosis of PAD. We investigated whether other parameters of ABI report sheet are useful to detect these patients.

Methods

We initially enrolled 3,912 patients (7,824 limbs) who underwent ABI for the first time. Subjects who have normal ABI were divided into the PAD group (n = 136) and the non-PAD group (n = 240) by lower extremity ultrasonography. We investigated blood pressures (BP) (systolic (SBP), diastolic (DBP), mean (mBP) and pulse pressure (PP)), heart rate, upstroke time (UT), and %mean arterial pressure (%MAP).

Results

SBP, mBP, PP, UT, and %MAP in the PAD group were significantly higher. A multivariate analysis showed that mBP, DBP, PP, UT and %MAP were independently associated with the presence of PAD (mBP: odds ratio (OR) 2.30, 95% confidence interval (CI) 1.22 - 4.37, P = 0.010; DBP: OR 0.52, 95% CI 0.28 - 0.97, P = 0.039; PP: OR 1.30, 95% CI 0.69 - 2.46, P = 0.041; UT: OR 3.40, 95% CI 2.03 - 5.83, P < 0.001; %MAP: OR 1.77, 95% CI 1.05 - 2.98, P = 0.031). Maximal area under the curve (AUC) of BPs for associating PAD was PP. The cut-off value of PP was 53.0 mm Hg (sensitivity 0.500, specificity 0.721, AUC 0.628, 95% CI 0.569 - 0.687).

Conclusions

The present study demonstrated that BPs are associated with PAD in patients with normal ABI. The measurement of BPs could provide additional information for the diagnosis of PAD.

Long-term use of ipragliflozin improved cardiac sympathetic nerve activity in a patient with heart failure: A case report

Ipragliflozin is the first SGLT2 inhibitor approved in Japan. Reported here is a case where long-term administration of ipragliflozin decreased the rate of re-hospitalization due to heart failure (HF). An 83-year-old man with chronic HF and diabetes mellitus (DM) was hospitalized four times in the last five years. He was discharged six months after his last hospitalization, but he continued to have class III HF according to the New York Heart Association classification (NYHA), and his DM was also not properly managed. Therefore, he received ipragliflozin. One year after initiation of ipragliflozin, he lost weight (body weight (BW): 79.0 to 76.2 kg), his levels of brain natriuretic peptide (BNP) decreased (191.4 to 122.5 mg/dL), and the class of his HF improved (class III to class II). The management of DM also improved (fasting blood glucose: 100 to 110 mg/dL; hemoglobin A1C: 6.8 to 6.6%). In addition, cardiac sympathetic nerve function evaluated with ¹²³I-metaiodobenzylguanidine cardiac-scintigraphy (¹²³I-MIBG) also improved (the average of the heart-to-mediastinum ratio in early and delayed phases; 1.44 to 2.17 in the early phase, 1.41 to 1.92 in the delayed phase, washout rate; 43.3 to 35.6). The patient was not re-hospitalized due to HF two years after administration of ipragliflozin started. A reduction in cardiac sympathetic nerve hyperactivity by an SGLT2 inhibitor might be one of the mechanisms of its cardio-protective effect, but clinical studies need to be conducted to verify this finding.

Weight Loss Mediated the Relationship between Tooth Loss and Mortality Risk

Tooth loss is a risk factor for increased mortality; however, the underlying mechanism remains unclear. This study aimed to evaluate the mediating effect of weight change on the relationship between tooth loss and mortality risk. This was a 10-y follow-up prospective cohort study using the data from the Japan Gerontological Evaluation Study (JAGES). The participants were independent older adults aged ≥65 y at baseline and were followed up from 2010 to 2020. The incidence of death in 2013 and 2020, incidence of >5% weight loss/gain in 2010 and 2013, and the number of remaining teeth in 2010 were used as the outcome, mediator, and explanatory variables, respectively. We conducted causal mediation analysis by fitting the Cox proportional hazard model, including possible confounders. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) of the total effect (TE), natural indirect effect (NIE), and proportion mediated (PM) were estimated. Among the 34,510 participants, the mean age was 72.6 (SD = 5.4) y, and 47.6% were men. From 2013 to 2020, 14.0% of the participants (n = 4,825) died, 60.5% (n = 20,871) had 0 to 19 remaining teeth, and 17.2% (n = 5,927) and 8.4% (n = 2,907) experienced >5% weight loss and gain, respectively. The mortality rate was 0.016 per person-year among those with ≥20 remaining teeth and 0.027 per person-year among those with 0 to 19 remaining teeth. Weight loss of >5% significantly mediated the association between tooth loss and higher mortality risk (TE: HR, 1.28 [95% CI, 1.16 to 1.40]; NIE: HR, 1.03 [95% CI, 1.02 to 1.04]; PM, 13.1%); however, we observed a slight mediating effect for >5% weight gain (NIE: HR, 1.003 [95%CI, 1.0001 to 1.01]; PM, 1.3%). The present study suggests that a clinically meaningful level of weight loss mediated the association between tooth loss and increased risk of mortality among independent older adults.

Assignment of 64 genes expressed in 28-day-old pig embryo to radiation hybrid map

A swine resource family was constructed at the National Institute of Animal Industry, Japan, in order to determine the genetic regions responsible for economically important traits, including fetus development. To identify genes expressed in the early stage of embryo development, we cataloged and mapped genes expressed in a 28-day-old normal pig embryo. In this effort, we have mapped 64 genes, which have map information in human genome onto a swine radiation hybrid (RH) map, IMpRH. These mappings provided additional chromosomal homologies between swine and human to improve the comparative map between the two species. The distribution of the genes assigned to swine chromosomes are as follows: 9 genes were assigned on SSC6; 6 genes each assigned on SSC5 and SSC14; 5 genes each assigned on SSC3, SSC4, and SSC8; 4 genes each assigned on SSC1, SSC7, SSC9, and SSC15; 3 genes each assigned on SSC2, SSC13 and SSCX; and 1 gene each assigned on SSC10, SSC11, and SSC16. Moreover, the present findings revealed 18 new chromosomal homologies between pig and human. Briefly, SSC3 regions were indicated to correspond with HSA1 and HSA10; SSC4 with HSA6; SSC5 with HSA2, HSA15, and HSA16; SSC6 with HSA3, HSA6, and HSA20; SSC7 with HSA11; SSC8 with HSA3, HSA6, and HSA7; SSC9 with HSA8; SSC13 with HSA1; SSC14 with HSA13; SSC15 with HSA19; SSC16 with HSA9.

Prognostic Value of 123I-BMIPP SPECT in Patients with Nonischemic Heart Failure with Preserved Ejection Fraction

Imaging of myocardial fatty acid metabolism using ¹²³I-betamethyl-p-iodophenyl-pentadecanoic acid (¹²³I-BMIPP) SPECT is useful for identifying high-risk patients with known ischemic heart disease. However, its utility for patients who have nonischemic heart failure with preserved ejection fraction is not well known. This study aimed to evaluate the prognostic value of the ¹²³I-BMIPP defect score in such patients. Methods: Of 804 consecutive patients who were admitted to the hospital because of acute heart failure and underwent ¹²³I-BMIPP SPECT, we identified 133 (mean age ± SD, 73 ± 13 y) who had normal coronary arteries by invasive coronary angiography and preserved left ventricular ejection fraction (≥50%) by echocardiography. ¹²³I-BMIPP defects were quantitatively scored to obtain summed defect scores in 17 segments of ¹²³I-BMIPP SPECT images. The patients were divided into 2 groups based on their score. The multivariate Cox model was used to assess a possible correlation between a higher score (≥4, n = 46) and major adverse cardiac events, including cardiac death, cardiovascular events, and hospitalization for heart failure, compared with a lower score (<4, n = 87). Results: During a mean follow-up of 2.5 y, 35 major adverse cardiac events occurred. The median scores in the high-score and low-score groups were 7.13 ± 4.21 and 1.29 ± 0.80, respectively. By multivariate Cox analysis, a higher score was associated with increased major adverse cardiac events, compared with a lower score (hazard ratio, 11.04; 95% confidence interval, 4.93-24.74; P < 0.001). Conclusion: This study demonstrated that the defect score by ¹²³I-BMIPP SPECT may have potential prognostic value in patients who have nonischemic heart failure with preserved ejection fraction.

Prevention of scald injury on the peritoneo-serosal surface in advanced gastric cancer patients treated with intraperitoneal hyperthermic perfusion

In attempts to avoid the side-effects derived from a scald on the peritoneo-serosal surface during intraperitoneal hyperthermic perfusion (IPHP) for advanced gastric cancer, a randomized study using cimetidine, a histamine H2-receptor antagonist, was carried out on 18 patients with advanced gastric cancer. Cimetidine, 50 mg/kg, was administered intravenously and immediately before IPHP. The background characteristics of the patients and the types of surgical treatment used were almost the same between each group of patients, whether or not cimetidine was given. The perfusion time in the cimetidine and control groups was 123 +/- 9 and 117 +/- 9 min, respectively. The inflow and outflow temperatures of the perfusate were 46.3 +/- 0.4 and 44.2 +/- 0.1 degrees C in the cimetidine group, respectively, whereas in the control group the temperatures were 46.0 +/- 0.3 and 44.1 +/- 0.2 degrees C, respectively. In the nine patients who were given cimetidine, the histamine concentrations in the peripheral blood increased significantly, compared to those in the nine controls; this resulted from the release of histamine into the circulating blood. Higher concentrations of protein were observed in the post-hyperthermic intraperitoneal exudate of the control group for 3-24 h after IPHP and, consequently, post-hyperthermic hypoproteinaemia was remarkable in the control group. These data suggest that when pre-IPHP cimetidine was prescribed for patients with gastric cancer treated with IPHP, the peritoneo-serosal surface was protected from scald injury and the side-effects of IPHP were reduced.

Stage-specific expression of a mouse homologue of the porcine 135kDa alpha-D-mannosidase (MAN2B2) in type A spermatogonia

The cDNA encoding a mouse homologue of porcine epididymis-specific 135kDa alpha-D-mannosidase (MAN2B2, D28521) was cloned from the mouse testis cDNA library. It was found that 1018 amino acids were coded in its open reading frame, and 62% of the amino acid sequence was identical to that of porcine MAN2B2. In the adult mouse, testis contained higher amounts of mRNA encoding the MAN2B2 homologue than the epididymis, though porcine MAN2B2 was mainly expressed in the narrow region between the caput and corpus epididymis. mRNA of the mouse MAN2B2 homologue was localized exclusively in spermatogonia in the testis. It was specifically expressed in type A spermatogonia at stages IX-XI of spermatogenesis and was detected there until the cell developed into type B spermatogonia. We conclude that the expression of the MAN2B2 homologue can serve as a good marker for the late stages of type A spermatogonia and may have an important role to play in the early step of spermatogenesis in mice.

Efficacy of Intravenous Administration of Landiolol in Patients With Acute Heart Failure and Supraventricular Tachyarrhythmia

BACKGROUND

Patients with acute heart failure (HF) complicated by supraventricular tachyarrhythmia (SVT) often receive continuous intravenous infusion of landiolol or diltiazem for rate control. It is unclear whether the interval from initiation of infusion to commencement of oral beta-blocker (BB) therapy differs for these two drugs.

METHODS

From January 2013 to July 2015, 94 consecutive patients were hospitalized for acute HF complicated by SVT. After 35 patients were excluded, the remaining 59 were divided into groups treated with diltiazem or landiolol. We investigated the blood pressure, heart rate, New York Heart Association classification, brain natriuretic peptide, chest X-ray film, echocardiographic findings (ejection fraction (EF)), time until commencement of oral BB therapy, and hospital stay.

RESULTS

There were no significant between-group differences of heart rate, blood pressure, or the severity of HF. The time until commencing oral BB therapy was significantly shorter in the landiolol group compared with the diltiazem group (median: 2 vs. 4 days, P = 0.002), but there was no significant difference in hospital stay. This interval was significantly shorter in patients with a reduced EF in the landiolol group (median: 2 days) compared with those with a reduced EF in the diltiazem group (median: 5 days, P = 0.008), and patients with a preserved EF in the landiolol group tended to have a shorter interval (median: 2 days) than those with a preserved EF in the diltiazem group (median: 4 days, P = 0.092).

CONCLUSIONS

Switching to oral BBs was accomplished earlier with landiolol than with diltiazem.

Effect of Copayment on Dental Visits: A Regression Discontinuity Analysis

Despite their prevalence and burdens, oral diseases are neglected in universal health coverage. In Japan, a 30% copayment (out of pocket) by the user and a 70% contribution by Japan’s universal health insurance (JUHI) are required for dental and medical services. From the age of 70 y, an additional 10% is offered by JUHI (copayment, 20%; JUHI, 80%). This study aimed to investigate the effect of cost on dental service use among older adults under the current JUHI system. A regression discontinuity quasi-experimental method was used to investigate the causal effect of the JUHI discount policy on dental visits based on cross-sectional data. Data were derived from the 2016 Japan Gerontological Evaluation Study. This analysis contained 7,161 participants who used JUHI, were aged 68 to 73 y, and responded to questions regarding past dental visits. Analyses were controlled for age, sex, number of teeth, and equalized household income. Mean ± SD age was 72.1 ± 0.79 y for the discount-eligible group and 68.9 ± 0.78 y for the noneligible group. During the past 12 mo, significantly more discount-eligible participants had visited dental services than noneligible participants (66.0% vs. 62.1% for treatment visits, 57.7% vs. 53.1% for checkups). After controlling for covariates, the effect of discount eligibility was significant on dental treatment visits (odds ratio [OR], 1.36; 95% CI, 1.32 to 1.40) and dental checkups (OR, 1.49; 95% CI, 1.44 to 1.54) in the regression discontinuity analysis. Similar findings were observed in triangular kernel-weighted models (OR, 1.38 [95% CI, 1.34 to 1.44]; OR, 1.52 [95% CI, 1.47 to 1.56], respectively). JUHI copayment discount policy increases oral health service utilization among older Japanese. The price elasticity for dental checkup visits appears to be higher than for dental treatment visits. Hence, reforming the universal health coverage system to improve the affordability of relatively inexpensive preventive care could increase dental service utilization in Japan.

T-477, a novel Ca(2+)- and Na(+) channel blocker, prevents veratridine-induced neuronal injury

To evaluate the effect of (R)-(+)-2-(4-chlorophenyl)-2, 3-dihydro-4-diethyl aminoacetyl-4H-1,4-benzothiazine hydrochloride (T-477), a novel Na(+)- and Ca(2+) channel blocker, on neuronal injury in vitro, we studied veratridine-induced injury in cultured rat hippocampal neurons. Neurons swelled extensively 10 min after the addition of veratridine, and returned to their initial size within 2 h. Intracellular Na(+) and Ca(2+) concentrations and amino acid release from the cells, in particular, that of glutamate, increased after the treatment with veratridine. Approximately 70% of neurons died within 24 h. T-477 inhibited both veratridine-induced swelling and death in a concentration-dependent manner. Moreover, T-477 concentration dependently reduced the increases in Na(+) and Ca(2+) influx and amino acid release. These results suggest that T-477 prevented the veratridine-induced influx of Na(+) and, thereby, reduced neuronal swelling. This, combined with the effects of T-477 on the inhibition of Ca(2+) influx and glutamate release, possibly by the blockade of Na(+) channels, may be the mechanism by which T-477 protects neurons from death induced by veratridine.

Assignment of T cell receptor (TCR) alpha-chain gene (A), beta-chain gene (B), gamma-chain gene (G), and delta-chain gene (D) loci on swine chromosomes by in situ hybridization and radiation hybrid mapping

Using the cDNA sequence of porcine T-cell receptor (TCR) alpha-, beta-, gamma-, and delta-chain genes, we screened a porcine BAC library to isolate clones containing these genes. The isolated BAC clones were confirmed to carry these TCR genes by partial nucleotide sequencing. Among the clones obtained in the present screening, two clones carried both the TCR alpha-chain gene (TRA) and the TCR delta-chain gene (TRD) while one clone each carried only the sequence of either TRA or TRD. This observation demonstrated that TRA and TRD are localized in close proximity on a swine chromosome. Also two clones contained the sequence of the TCR beta-chain gene (TRB), and two clones contained the sequence of TCR gamma-chain gene (TRG). Fluorescence in situ hybridization using the above BAC clones as probes revealed that TRA and TRD, TRB, and TRG loci reside on swine chromosomes 7q15.3-->q21, 18q11.3-->q12, and 9q21-->q22, respectively. The chromosome positions of TRA and TRB are consistent with those determined by somatic cell hybrid analysis (Rettenberger et al., 1996). In addition, RH mapping of these genes was performed using the INRA-University of Minnesota RH panel DNA. The result confirmed the position of TRA and TRB reported earlier (http://imprh.toulouse.inra.fr/), and further demonstrated that TRG was located 11 cR away from genetic marker SW989 toward the marker S0019.

Construction of a high-resolution comparative gene map between swine chromosome region 6q11-->q21 and human chromosome 19 q-arm by RH mapping of 51 genes

A comprehensive and comparative map was constructed for the porcine chromosome (SSC) 6q11-->q21 region, where the gene(s) responsible for the maldevelopment of embryos are localized using swine populations of the National Institute of Animal Industry, Japan (NIAI). Since the chromosomal region corresponds to a region of human chromosome (HSA) 19q13.1-->q13.3 based on bi-directional chromosome painting, primer pairs were designed from porcine cDNA sequences identified, on a sequence comparison basis, as being transcripts from genes orthologous to those in the HSA region. Fifty-one genes were successfully assigned to a swine radiation hybrid (RH) map with LOD scores greater than 6. ERF and PSMD8 genes were assigned to SSC4 and SSC1, respectively. The remaining 49 genes were assigned to SSC6, demonstrating that the synteny between the SSC6 and HSA19 chromosomal regions is essentially conserved, therefore confirming, the results of bi-directional chromosome painting. However, when examined precisely, rearrangements have apparently occurred within the region of conserved synteny. For the ERF and PSMD8 genes assigned to SSCs other than SSC6, additional mapping using somatic cell hybrid (SCH) panels was performed to confirm the results of RH-mapping.

Conservation of the syntenies between porcine chromosome 7 and human chromosomes 6, 14 and 15 demonstrated by radiation hybrid mapping and linkage analysis

Comparative mapping studies facilitate the identification of genes located in quantitative trait locus (QTL) regions in domestic animals by utilizing information from the human genome. Radiation hybrid (RH) mapping is effective for this purpose because of its high resolution in ordered gene mapping on chromosomes. We constructed an RH map of pig chromosome 7, by adding 23 markers associated with genes. This RH map clearly demonstrated the mosaic of homology between pig chromosome 7 (SSC7) and human chromosomes 6, 14 and 15 at a 'gene' level, and was confirmed by linkage analysis. Clarification of the homology of SSC7 to human chromosomes will contribute to the elucidation of the gene(s) responsible for QTL detected on this chromosome.

Effects on tumour microcirculation in mice of misonidazole and tumour necrosis factor plus hyperthermia

We examined the effects of misonidazole (MISO) and recombinant human tumour necrosis factor (rh-TNF) on tumour blood flow in mice given hyperthermic treatments. MISO (500 mg kg-1) or rh-TNF (6 x 10(4) unit kg-1) was administered intraperitoneally (i.p.) prior to hyperthermia to nude mice bearing a xenoplanted human gastric cancer and tumour blood flow was measured by a hydrogen diffusion method based on polarographic determinations. MISO plus hyperthermia produced a temperature-dependent decrease in blood flow and, at 43.5 degrees C, the flow decreased to 15-30% of control and remained low for up to 24 h. Blood flow following rh-TNF plus hyperthermia was less than that at the same temperatures following MISO plus hyperthermia, and, at 43.5 degrees C, the flow decreased to 10-20% of control and remained low for up to 48 h. Tumour growth delay was closely related to the duration of the decrease in blood flow. Thus, the profound decrease in tumour blood flow following hyperthermia plus MISO or rh-TNF and the consequential tumour regression may well be of potential clinical significance.

A dense comparative gene map between human chromosome 19q13.3-->q13.4 and a homologous segment of swine chromosome 6

The human chromosome (HSA)19q region has been shown to correspond to swine chromosome (SSC) 6q11-->q21 by bi-directional chromosomal painting and gene mapping. However, since the precise correspondence has not been determined, 26 genes localized in HSA19q13.3-->q13.4 were assigned to the SSC6 region mainly by radiation hybrid (RH) mapping, and additionally, by somatic cell hybrid panel (SCHP) mapping, and fluorescent in situ hybridization (FISH). Out of the 26 genes, 24 were assigned to a swine RH map with LOD scores greater than 6 (threshold of significance). The most likely order of the 24 genes along SSC6 was calculated by CarthaGene, revealing that the order is essentially the same as that in HSA19q13.3-->q13.4. For AURKC and RPS5 giving LOD scores not greater than 6, SCHP mapping and FISH were additionally performed; SCHP mapping assigned AURKC and RPS5 to SSC6q22-->q23 and SSC6q21, respectively, which is consistent with the observation of FISH. Consequently, all the genes (26 genes) examined in the present study were shown to localize in SSC6q12-->q23, and the order of the genes along the chromosomes was shown to be essentially the same in swine and human, though several intrachromosomal rearrangements were observed between the species.