Evaluation of routine sonography for early detection of pancreatic cancer

The diagnostic accuracy of routine abdominal sonography for the detection of pancreatic cancer was examined. During the one-year period of 1994, sonographic examination of the upper abdominal region was performed 12,761 times on a total of 9410 patients for the screening of abdominal disorders. In 655 cases (7%) part of the pancreas could not be observed. Based on the "Diagnostic criteria for pancreatic cancer" published by the Japanese Society of Ultrasound in Medicine, sonographic finding was evaluated to be positive for pancreatic tumor in a total of 411 cases. At the end of 1995, 51 patients were proven to have pancreatic cancer, and 45 of these cases were ductal adenocarcinoma. In 26 cases the tumor was surgically resected. Fifty cases were true sonographic positives and one was a false negative. The sensitivity, specificity, overall accuracy, and positive and negative predictive values of sonography for pancreatic cancer were 98.0%, 95.9%, 95.9%, 12.2% and 100.0%, respectively. Among the 50 true positive cases, the tumor diameter was less than 1 cm in four (8%). In conclusion, the diagnostic accuracy of sonography for the detection of pancreatic cancer is sufficiently high. Therefore, a detailed study aimed at mass screening for pancreatic cancer using sonography as the main modality seems warranted as a countermeasure for the rapid increase of pancreatic cancer in Japan.

DARPP-32 expression arises after a phase of dysplasia in oesophageal squamous cell carcinoma

This is the first report to correlate DARPP-32 immunoreactivity (dopamine and cAMP-regulated phosphoprotein, M_r 32 000) to clinicopathological status in human cancer. DARPP-32 is recognised as a neuronal protein. A recent study demonstrated that DARPP-32, and a truncated isoform t-DARPP, are overexpressed in gastric carcinoma during the process of carcinogenesis. The biological function of DARPP-32, however, is still unclear. The purpose of this study was to clarify the roles of DARPP-32 and t-DARPP in oesophageal squamous cell carcinoma (OSCC). Initially, we investigated DARPP-32 and t-DARPP expression in OSCC cell lines by Reverse transcription–polymerase chain reaction and Western blot. DARPP-32 expression was observed in four out of seven (57.1%) cell lines, but t-DARPP expression was not observed in any cell lines. In oesophageal tissue sample, DARPP-32 expression was observed in four out of seven (57.1%) tumour tissues, while t-DARPP was not observed in any tissues. Subsequently, DARPP expression was assessed by immunohistochemistry, using a polyclonal antibody, in tissue sections from 122 patients with primary OSCC. DARPP immunoreactivity was not observed in any normal oesophageal mucous membranes. On the other hand, positive DARPP immunostaining was detected in 37 patients (30.3%) and correlated inversely with pathologic stage (P=0.0284), pT (P=0.0438), pN (P=0.0303) and tumour size (P=0.012). The overall survival rate was worse in patients with DARPP-negative tumours than in patients with DARPP-positive tumours (P=0.0453). Interestingly, DARPP expression was observed in only one out of 45 cases of dysplasia. These observations suggest that DARPP-32 (rather than t-DARPP) expression arises after a phase of dysplasia in OSCC, and that tumours expressing DARPP-32 progress less rapidly than DARPP-32-negative tumours.

Characteristics of impaired chemotactic function in cord blood leukocytes

Mobilities of cord blood granulocytes were studied using the agarose plate method and Boyden's chamber method. In the agarose plate, granulocytes of cord blood were shown to have moderately decreased responses in chemotaxis and chemokinesis induced by Escherichia coli-derived chemotactic factor and/or zymosan-activated serum, whereas they were shown to have a normal capacity of random mobility. Although their distance and index of chemotaxis or chemokinesis in the agarose plate were significantly less than those of adult granulocytes, response rate in both types of mobility were evidently higher compared with those in patients with chemotactic defect. Furthermore, there is a difference between chemotactic responses of cord blood granulocytes to E. coli-derived chemotactic factor and to zymosan-activated serum in the agarose plate method. Using the latter, a more distinguishable difference between chemotactic responses of cord blood granulocytes and adult granulocytes was shown. The Boyden's chamber method tended to show a more significant difference between chemotactic responses of granulocytes of cord blood and adults than in the agarose plate method.

Inhibition by xiao-chai-hu-tang (TJ-9) of development of hepatic foci induced by N-nitrosomorpholine in Sprague-Dawley rats

The effect of Xiao-chai-hu-tang (TJ-9) on hepatocarcinogenesis induced by N-nitrosomorpholine (NNM) was investigated in male Sprague-Dawley rats. Rats were given normal chow pellets containing 0.5% or 1.0% TJ-9 until the end of the experiment, and drinking water containing NNM for 8 weeks. Pre-neoplastic and neoplastic lesions staining for gamma-glutamyl transpeptidase (GGT) or the placental type of glutathione-S-transferase (GST-P) were examined histochemically. In Week 15, quantitative histological analysis showed that prolonged treatment with 0.5% TJ-9 significantly reduced the number and volume of GGT-positive and GST-P-positive hepatic lesions. Treatment with 1.0% TJ-9 inhibited the development of GGT-positive and GST-P-positive lesions, but was less effective than 0.5% TJ-9. Administration of 0.5% TJ-9 also caused a significant increase in the proportion of helper T lymphocytes and a significant decrease in the labeling index of pre-neoplastic lesions. These findings indicate that TJ-9 inhibits the development of hepatic foci.

Epidemiologic analysis of diabetic patients on chronic dialysis

We retrospectively surveyed all of the available medical records of 404 (191 females and 213 males) chronic dialysis patients, of whom 16 (4%) had insulin-dependent diabetes mellitus (IDDM) and 388 (96%) non-insulin-dependent diabetes mellitus (NIDDM). The patients were among 2,214 dialysis patients in Okinawa, Japan, of whom 443 were diabetic. The patients entered a large population-based dialysis registry. The mean duration from the diagnosis of diabetes mellitus (DM) to dialysis was 181.6 months in the IDDM patients and 150.4 months in the NIDDM patients. The NIDDM patients were classified into four subgroups according to their status when DM was first suspected. The duration from the diagnosis of DM until the onset of dialysis treatment was significantly shorter than in any other subgroup or in the IDDM subgroup with major vascular disease (131.9 months). Otherwise, the course of renal disease in NIDDM patients was similar to that in IDDM individuals. Most of our dialysis patients with DM had NIDDM. In most of the NIDDM patients, the diagnosis had been delayed for several years for unknown reason. However, if diagnosed early, NIDDM shows a clinical time course until dialysis similar to that of IDDM. Whether NIDDM patients contract chronic renal disease at an equal incidence to that of IDDM patients and the fraction of all diabetic patients accepted for chronic dialysis remain to be determined.

Suppression by pravastatin, an inhibitor of p21ras isoprenylation, of hepatocarcinogenesis induced by N-nitrosomorpholine in Sprague-Dawley rats

The effect of pravastatin, an inhibitor of p21ras isoprenylation, on hepatocarcinogenesis induced by N-nitrosomorpholine and on p21ras isoprenylation were investigated in male Sprague-Dawley rats. Rats received i.p. injections of pravastatin (10 and 20 mg kg(-1) body weight) every other day and, from the beginning of the experiment, were given drinking water containing N-nitrosomorpholine for 8 weeks. Visible white nodules and hepatic lesions staining positively for gamma-glutamyl transpeptidase or glutathione-S-transferase, placental type, were examined macroscopically or histochemically. In week 15, pravastatin at both dosages significantly reduced the incidence, number and volume of visible white nodules. Quantitative histological analysis also showed that prolonged administration of pravastatin at both dosages resulted in significant reductions in the number and percentage area of hepatic lesions positive for gamma-glutamyl transpeptidase and glutathione-S-transferase, placental type. Administration of pravastatin also significantly decreased the amount of membrane-associated p21ras in the tumour and the labelling index of neoplastic nodules and increased the apoptoic indices of neoplastic nodules. These findings indicate that pravastatin suppresses hepatocarcinogenesis and suggest that this effect might be related to pravastatin's inhibition of p21ras isoprenylation and its subsequent inhibition of cell proliferation and induction of apoptosis in neoplastic lesions.

Blockade of Th1 chemokine receptors ameliorates pulmonary granulomatosis in mice

Sarcoidosis is a granulomatous disease of unknown aetiology. We identified immunological targets for the treatment of pulmonary granulomatosis using a murine model generated with Propionibacterium acnes. Sensitisation and challenge using heat-killed P. acnes and dendritic cells (DCs) were performed to produce pulmonary granulomatosis in C57BL/6 mice. Immunological analyses using ELISA as well as cDNA microarray analysis were used to search for cytokines or chemokines associated with the formation of granulomas in the lungs. Co-administration of P. acnes and DCs reproducibly induced the formation of pulmonary granulomas, which resembled sarcoid granulomas. The cDNA microarray assay demonstrated that the gene expression of CXCL9 and CXCL10, ligands for CXCR3, and of CCL4, a ligand for CCR5, was strongly upregulated during granulomatosis. ELISA confirmed that levels of CXCL9 and CXCL10 as well as T-helper (Th)1 cytokines and chemokines including tumour necrosis factor-α and interferon-γ were elevated in bronchoalveolar lavage fluid (BALF). The blockade of Th1 chemokine receptors using TAK-779, a dual blocker for CXCR3 and CCR5, led to reduced numbers of CXCR3+CD4+ and CCR5+CD4+ T-cells in BALF. Furthermore, administration of TAK-779 ameliorated the granulomatosis. The targeted inhibition of Th1 chemokines might be useful for inhibiting Th1-biased granulomatous diseases, including sarcoidosis.

Biochemical studies on the H-2K antigens of the MHC mutants bm3 and bm11

Biochemical analyses of the H-2K-gene products of the C57BL/6 mutant strains, bm3 and bm11, have been carried out in order to characterize the structural relationships among these antigens. From comparative tryptic peptide mapping of cyanogen bromide fragments from the mutant and parent Kb glycoproteins and from preliminary amino-acid sequence analyses, a number of discrete differences have been discerned. Two sites of difference at amino residues 77 and 89 in the Kbm3 glycoprotein are noted relative to Kb. An alteration at residue 77 similar or identical to that seen in Kbm3 is present in the K antigen of the bm11 mutant. Because our techniques sample only 75 to 80 percent of the extracellular portion of H-2Kb, other undetected changes are possible. However, our present findings are most consistent with the conclusion that only very limited differences exist between mutant and parent molecules. Further, taken together with CML (cell-mediated-lymphocytotoxicity) reaction patterns (Melief et al. 1980), the biochemical data support the hypothesis that the proposed structural alterations in the Kb mutant glycoproteins are directly related to their observed immunological specificity.

Enhancement of osteoclastogenic activity in osteolytic prostate cancer cells by physical contact with osteoblasts

BACKGROUND

The interaction between prostate cancer cells and osteoblasts is critical for the development of bone metastasis. Metastatic cancer cells may physically contact osteoblasts in the bone microenvironment; however, the biological significance of this interaction is not fully understood.

METHODS

Human prostate cancer cells (the osteolytic cell line PC-3 and the osteoblastic cell line MDA-PCa 2b) and human osteoblasts (hFOB1.19) were cocultured under two different conditions (bilayer and contact conditions). Differential gene expression profiles of prostate cancer cells were then investigated using microarray analysis. Differentially expressed genes were analysed using RT-PCR and western blotting, and the effect of anti-cadherin neutralising antibodies on their expression was assayed. The osteoclastogenic activity of cells grown under these different conditions was also investigated using an in vitro assay.

RESULTS

When PC-3 or MDA-PCa 2b cells were cocultured with hFOB1.19 cells under contact conditions, the expression of eight genes was upregulated and that of one gene was downregulated in PC-3 cells compared with gene expression in bilayer culture. No differentially expressed genes were detected in MDA-PCa 2b cells. Four of the eight upregulated genes (interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2), IL-6 and the third component of complement (C3)) have already been reported to participate in osteoclastogenesis. Indeed, a cell lysate of PC-3 cells grown under contact coculture conditions significantly enhanced osteoclastogenesis in vitro (P<0.005). neutralisation of cadherin-11 with a specific antibody inhibited upregulation of COX-2 and C3 mRNA in PC-3 cells. In contrast, neutralisation of N-cadherin induced upregulation of COX-2 mRNA.

CONCLUSION

Physical contact between osteolytic prostate cancer cells and osteoblasts may upregulate osteoclastogenesis-related gene expression in prostate cancer cells and enhance osteoclastogenesis. Additionally, cadherin-11 and N-cadherin are involved in this process. These data provide evidence supporting new therapies of prostate cancer bone metastasis that target direct cancer-cell-osteoblast cell-cell contact.

Primary structure of murine major histocompatibility complex alloantigens: completion of the sequence of the amino-terminal 284 residues of H-2Kb

The primary structure of the COOH-terminal cyanogen bromide (CNBr) cleavage fragment Ic (CN-Ic) of the extracellular portion of the murine histocompatibility antigen H-2Kb has been completed. CN-Ic contains a site of papain cleavage which has been utilized for solubilizing H-2Kb by cleaving off the membrane integrating portion of the molecule. The amino acid sequence of CN-Ic has been determined by using peptides recovered after trypsin digestion of CN-Ic before and after blockage of lysine groups with citraconic anhydride. Overlapping sequences for the tryptic fragments were obtained by amino-terminal sequence analysis. The sequence of fragment CN-Ic, which spans residues 229-284 in H-2Kb, is as follows: Glu-Leu-Val-Glu-Thr-Arg-Pro-Ala-Gly-Asp-Gly-Thr-Phe-Gln-Lys-Trp-Ala-Ser-Val-Val-Pro-Leu-Gly-Lys-Glu-Gln-Tyr-Tyr-Thr-Cys-His-Val-Tyr-Gln-Gln-Gly-Leu-Pro-Gln-Pro-Leu-Thr-Leu-Arg-Trp-Asp-Glu-Pro-Pro-Ser-Thr-Val-Ser-Asn-Met. This amino acid sequence determination completes the primary structure of the amino terminal 284 residues of H-2Kb, that portion of this histocompatibility antigen which is external to the cell membrane and which contains antigenic determinants. It was also possible to identify Val-281 as a papain cleavage site within CN-Ic. The completed structure was analyzed solely by radiochemical methods. The structure obtained for H-2Kb is 71% homologous to the reported structure of HLA-B7, a human homologue.

Successful treatment of fulminating complications associated with extensive rhabdomyolysis by plasma exchange

The first successful treatment by plasma exchange of acute renal failure and disseminated intravascular coagulation, as well as liver and central nervous system damage, was achieved in two patients with severe multiorgan damage associated with extensive muscle tissue damage caused by heatstroke and/or electrical injury. Substances derived from damaged muscle tissue, such as myoglobin and enzymes, were efficiently removed by a cellulose acetate membrane filter. Improvement of consciousness, disturbance, coagulation disorder, and renal failure were observed. The disorders associated with extensive rhabdomyolysis seem to be a promising indication for this therapy. Plasma exchange with a membrane filter is useful for treatment of patients with renal failure, being readily connected on-line with conventional dialysis.

Modifying effects of a mixture of acetaminophen, aspirin, dipyrone and ethenzamide on a multiorgan initiation model and its carcinogenicity in male F344 rats

Six-week-old male F344 rats were given a mixture of 0.01% diethylnitrosamine, 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine and 0.02% N-methyl-N'-nitro-N-nitrosoguanidine in their drinking water for 1 week. When 0.8%, 0.4%, or 0% of a mixture of non-steroidal anti-inflammatory drugs (NSAIDs) (acetaminophen, aspirin, dipyrone plus ethenzamide) was given after treatment with initiators in their food from weeks 2 to 68, the incidences of liver cell tumors in the rats were 68% (P < 0.001), 25% and 8%, respectively, but those of other tumors were not different. Administration of NSAIDs from weeks 2 to 104 without initiators showed no carcinogenicity. From the results of medium-term liver bioassay, it was suggested that dipyrone and ethenzamide had promoting effects and acetaminophen had an inhibitory effect on rat hepatocarcinogenesis.

Nerve growth factor derived from bronchial epithelium after chronic mite antigen exposure contributes to airway hyperresponsiveness by inducing hyperinnervation, and is inhibited by in vivo siRNA

BACKGROUND

Bronchial asthma is a chronic allergic airway inflammatory disease. Neurotrophins, including nerve growth factor (NGF), play an important role in the pathogenesis of asthma. However, the effects of NGF derived from epithelium on airway hyperresponsiveness (AHR) after antigen sensitization/exposure remain uncertain.

OBJECTIVE

In this study, we examined the role of NGF on AHR after chronic antigen exposure and the effect of inhibiting NGF by in vivo siRNA on AHR exacerbation.

METHODS

We generated chronic mouse models of bronchial asthma using house-dust mite antigen (Dermatophagoides pteronyssinus; Dp). NGF concentrations in bronchoalveolar lavage fluid (BALF), lung histopathology, hyperresponsiveness, and related neuronal peptides and cytokines in supernatants of lung homogenates were determined.

RESULTS

NGF in BALF was increased in a dose- and time-dependent manner, and was expressed primarily in bronchial epithelium. Nerve fibres and substance P-positive fibres were detected in subepithelium of Dp-sensitized and challenged mice over 4 weeks of mite antigen exposure. AHR was positively correlated with NGF concentration and nerve fibre innervation. AHR, modulation of innervation, and increased substance P were inhibited by in vivo administration of siRNA that targeted NGF, although the inhibition of NGF did not affect allergic inflammation and subepithelial fibrosis.

CONCLUSION AND CLINICAL RELEVANCE

These findings suggest that NGF derived from bronchial and alveolar epithelium plays an important role in AHR after chronic exposure to mite antigen. NGF inhibition could potentially manage bronchial asthma, including AHR.

Biochemical studies on the H-2K antigens of the MHC mutant bml

Biochemical analysis of the H-2K-gene product from the MHC mutant strain bml and from the C57BL/6 parent strain has been carried out in order to characterize the structural differences between parent and mutant K-gene products. Based on comparative tryptic peptide mapping of the cyanogen bromide fragments from these glycoproteins, two peptide differences were localized to the CN-Ia fragment. Partial amino-acid sequence analysis revealed two alterations in the primary structure of Kbml involving substitutions of tyrosine for arginine at position 155, and tyrosine for leucine at position 156. Both of these amino-acid replacements require a minimum of two nucleotide base changes at the nucleic acid level. These changes were the only alterations noted differentiating the Kbml and Kb glycoproteins. However, because our techniques allow us to analyze only 75 to 80 percent of the extra cellular portion of H-2Kb, it is possible there are other undetected changes. Nonetheless, the biochemical data are consistent with the hypothesis that the structural alterations noted in the Kbml mutant glycoprotein are directly related to the observed immunological specificity relative to the parent Kb molecule. Peptide comparisons of the Kb molecules of two C57BL/6 sublines and of the H-2b lymphoblastoid cell line, EL-4, disclosed no difference.

Amino acid sequence of the carboxyl-terminal hydrophilic region of the H-2Kb MHC alloantigen. Completion of the entire primary structure of the H-2Kb molecule

The amino acid sequence of the COOH-terminal hydrophilic region of the H-2Kb histocompatibility antigen was determined. The sequence was completed by analyses of four CNBr fragments obtained from the intact molecule as well as tryptic peptides. This region was composed of 39 amino acid residues with a cluster of basic residues at the NH2 terminus and localized positions 308-346 of the H-2Kb molecule. These sequence data, together with those reported for the NH2-terminal 284 residues [Martinko, J. M., Uehara, H., Ewenstein, B. M., Kindt, T. J., Coligan, J. E., & Nathenson, S. G. (1980) Biochemistry 19, 6188-6193] and for the intramembranous segment [Uehara, H., Coligan, J. E., & Nathenson, S. G. (1981) Biochemistry (preceding paper in this issue)], provided the complete primary structure of the H-2Kb molecule. This is the first histocompatibility antigen for which the entire primary structure is determined.

Primary structure of murine major histocompatibility alloantigens: amino acid sequence of the cyanogen bromide fragment Ia (positions 139-228) from the H-2Kb molecule

The complete amino acid sequence of the cyanogen bromide (CNBr) fragment Ia (CN-Ia) from the murine histocompatibility antigen H-2Kb has been obtained by using radiosequence methodology. This glycopeptide is the largest CNBr cleavage product of the H-2K molecule and extends from position 139 to position 228. The sequence determined for CN-Ia was Ala-Ala-Leu-Ile-Thr-Lys-His-Lys-Trp-Glu-Gln-Ala-Gly-Glu-Ala-Glu-Arg-Leu-Arg-Ala -Tyr-Leu-Glu-Gly-Thr-Cys-Val-Glu-Trp-Leu-Arg-Arg-Tyr-Leu-Lys-Ans-Gly-(Asn)-Ala- Thr-Leu-Leu-Arg-Thr-Asp-Ser-Pro-Lys-Ala-His-Val-Thr-His-His-Ser-Arg-Pro-Asp-Asp -Lys-Val-Thr-Leu-Arg-Cys-Trp-Ala-Leu-Gly-Phe-Tyr-Pro-Ala-Asp-Ile-Thr-Leu-Thr-Tr p-Gln-Leu-Asn-Gly-Glu-Glu-Leu-Ile-Gln-Aps-Met. The data were obtained by analysis of fragments derived by thrombic, tryptic, chymotryptic, and V8 protease digestion of CN-Ia. A carbohydrate moiety is attached to Asn at position 176. Homology between this 90 amino acid stretch of H-2Kb and HLA-B7 [Orr, H. T., Lopez de Castro, J. A., Lancer, D., & Strominger, J. L. (1979) Biochemistry 18, 5711] is 68%, and differences are noted at positions 176, 177, and 178 which in the H-2 molecule are the attachment region for a second carbohydrate moiety. No carbohydrate was detected in this position for HLA-B7 [Orr, H. T. Lopez de Castro, J. A. Lancet, D., & Strominger, J. L. (1979) Biochemistry 18, 5711].

Pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) stimulate interleukin-6 production through the third subtype of PACAP/VIP receptor in rat bone marrow-derived stromal cells

Regulation of Interleukin-6 (IL-6) production in bone marrow (BM)-derived stromal cells by neuropeptides, pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP), was examined. Both forms of PACAP, PACAP-27 and PACAP-38, as well as VIP significantly increased IL-6 production by rat BM-derived stromal cells at physiological concentrations ranging from 10(-10)-10(-8) M. The three related peptides (PACAP-27, -38, and VIP) stimulated the production of both cAMP and inositol 1,4,5-trisphosphate (IP3) in rat BM-derived stromal cells with similar 50% effective concentrations. The stimulatory potency of the three related peptides for the production of IL-6, cAMP, and IP3 was almost consistent, suggesting that the dual signaling transduction pathways may be involved in PACAP/VIP-induced IL-6 production in rat BM-derived stromal cells. The messenger RNA (mRNA) for the third subtype of PACAP receptor (PVR3) was found to be abundantly expressed in both BM-derived stromal cells and the BM tissue, whereas little of the mRNA for type 1 (PVR1) nor type 2 (PVR2) was detected. Furthermore, the mRNAs for PACAP and VIP were detected in the BM tissue, suggesting that both PACAP/VIP and PVR3 are synthesized in vivo in the BM. The results shown in this paper suggest that PACAP/VIP and their receptor play an important role in the IL-6 production and perhaps in the hematopoiesis in the BM.

Imaging findings of urachal mucinous cystadenocarcinoma associated with pseudomyxoma peritonei

Pseudomyxoma peritonei is an uncommon neoplastic condition in which gelatinous fluid-like materials are observed in the peritoneal cavity caused by the dissemination of mucinous adenocarcinoma. Although ruptured appendiceal mucocele is the most common cause, tumors arising from other organs may also cause pseudomyxoma peritonei. We report the imaging findings of an extremely rare case of urachal mucinous adenocarcinoma associated with pseudomyxoma peritonei on computed tomography and magnetic resonance imaging with histopathologic correlation.

Robustness of adult female survival maintains a high-density sika deer (Cervus nippon) population following the initial irruption

Context Irruption of large herbivore populations is characterised by three distinct phases: (1) an exponential increase in population to a peak abundance; (2) a population crash; and (3) a second increase to another population peak, typically lower than the first peak of abundance. However, there has been little study of age- and sex-specific factors that affect the post-initial irruption interactions with food sources. Aims We aimed to investigate annual survival rates of sika deer (Cervus nippon Temminck, 1838) in the sequent irruption of a population on Nakanoshima Island, Lake Toya, Japan, with a chronically high density during the period 2002–12. Methods Survival monitoring data were obtained for 219 individuals (93 males and 126 females) using radio-collars. Annual survival was quantified, and related factors, i.e. deer abundance and winter severity, were determined by model selection using Akaike information criterion values. Key Results The results showed that annual survival rates across sexes and age classes (fawn, yearling, prime-aged, old) decreased with increasing population density, snow depth and winter precipitation. Winter severity had a greater effect on adult survival than density regulation. Nevertheless, female adult survival was maintained at a high level, with a mean of 0.84 (95% CI: 0.80–0.88). Key conclusions Robust survival rates for adult females might contribute to the maintenance of a high-density sika deer population in the post-initial irruption. Implications We suggest that in the absence of predation and hunting, sika deer population is not able to self-regulate to the density level that avoids an irreversible impact on plants.

Hyperventilation and cold-pressor stress echocardiography for noninvasive diagnosis of coronary artery spasm

We report the usefulness of 2-dimensional echocardiography during the cold-pressor test immediately after hyperventilation for noninvasive diagnosis of coronary vasospasm in 43 patients with suspected vasospastic angina. The stress test consisted of hyperventilation for 6 minutes, followed by cold water pressor stress for 2 minutes under continuous electrocardiographic and echocardiographic monitoring. Coronary angiography with an intracoronary injection of acetylcholine was performed within 2 weeks after the stress test. Coronary spasm was observed in 33 patients by angiography. Multivessel spasm was diagnosed in 26 patients by stress echocardiography and in 23 patients by angiography. The stress-induced wall motion abnormalities occurred earlier than the ST-segment changes and chest pain. The wall motion abnormalities shown on the echocardiogram correlated well with the vascular territories of the coronary artery that had the spasm. The sensitivity, specificity, and diagnostic accuracy of hyperventilation and cold-pressor stress echocardiography for detecting vasospastic angina against coronary angiography with an intracoronary injection of acetylcholine were 91%, 90%, and 91%, respectively. However, the sensitivity, specificity, and diagnostic accuracy of hyperventilation and cold-pressor stress electrocardiography for detecting vasospastic angina were 48%, 100%, and 60%, respectively. No major side effects were observed during or after the stress test. Echocardiographic monitoring during the stress test detected spasm unaccompanied by either ST- segment changes or chest pain and revealed the location of multivessel coronary spasm. Hyperventilation and cold-pressor stress echocardiography is thus a noninvasive and useful tool for the diagnosis of vasospastic angina.

Doxapram accentuates white matter injury in neonatal rats following bilateral carotid artery occlusion

The effect of the respiratory stimulant, doxapram, on white matter damage was investigated in neonatal rats under cerebral ischemia. Five-day-old rats underwent bilateral carotid artery occlusion with or without 50 mg/kg i.p. of doxapram. Their brains were neuropathologically examined 48 h later. Doxapram induced about a 20% decrease of PCO(2) for 90 min, but did not cause any neuropathological abnormalities. Bilateral carotid artery occlusion resulted in mild cerebrocortical lesions in 67% of pups, and white matter lesions in the internal capsule in 44%. Doxapram, in addition to bilateral carotid artery occlusion, produced more severe white matter injury in the internal capsule (injury score; 0.67+/-0.87 vs. 1.70+/-0.48, P<0.05) and in the subcortical white matter (0.33+/-0. 67 vs. 1.10+/-0.54, P<0.05). These results demonstrated that the use of doxapram under an ischemic condition accentuates white matter damage in neonatal rats.