Ca(2+)-free, high-Ca2+ coronary perfusion suppresses contractility and excitation-contraction coupling energy

We studied the mechanoenergetic effects of a short-term Ca(2+)-free, high-Ca2+ Tyrode solution coronary perfusion in eight excised, cross-circulated canine hearts. The perfusion protocol consisted of coronary perfusion with Ca(2+)-free Tyrode solution for 10 min followed by high-Ca2+ (16 mM) Tyrode solution for 5 min. This new protocol successfully induced acute contractile failure in seven hearts, without myocardial ultrastructural changes. We studied the end-systolic pressure-volume relation (slope = Emax, a contractility index) and the relation between oxygen consumption per beat (VO2) and systolic pressure-volume area (PVA) in these failing hearts. These hearts had no increase in end-diastolic pressure at a given volume, a 40% decrease in Emax and a proportional decrease in the PVA-independent VO2 for 1-4 h, but no decrease in the oxygen cost of PVA, defined as the slope of the VO2-PVA relation. The oxygen cost of Emax for Ca2+ handling, defined as the slope of the relation between PVA-independent VO2 and Emax, was unchanged in the failing hearts. We conclude that the present protocol induced left ventricular contractile failure, primarily involving the suppression of Ca2+ handling energy for excitation-contraction coupling.

The high hepatocarcinogen susceptibility of LEC rats is genetically independent of abnormal copper accumulation in the liver

We previously reported that LEC rats, which show a spontaneous occurrence of liver injury and hepatocellular carcinoma (HCC), are highly susceptible to chemical carcinogens such as diethylnitrosamine (DEN). Since abnormal copper accumulation in the liver of LEC rats was found to be a cause of liver injury, it is necessary to elucidate whether the carcinogen susceptibility of LEC rats is related to the accumulation of copper in the liver. In this study we have examined the relationship between the susceptibility of FI [LEC x LEA or LEC x Fischer 344 (F344)] and FI backcross rats to DEN and hepatic copper concentration, as copper accumulation has been demonstrated to be inherited as an autosomal recessive trait. The groups of F1 and F1 backcross rats were given a single intraperitoneal injection of DEN (20 mg/kg wt) and subjected to a modified Solt-Farber protocol for assaying glutathione S-transferase placental form (GST-P)-positive foci. The hepatic copper concentration was examined by atomic absorption. Although no F1 rats showed a high copper concentration in the liver, the numbers of foci were as high as those in LEC rats which accumulate copper. Backcross rats separated into high and low copper concentration groups at an almost 1:1 ratio, but there was no significant difference in the mean numbers of foci between these two groups. The results clearly indicate that the high susceptibility of LEC rats to DEN is genetically independent of copper accumulation in the liver. A possible dominant inheritance of this high carcinogen susceptibility was suggested. Biochemical measurement of cytochromes P450 and b5 in the liver of F1 rats indicated that alterations in drug metabolizing enzymes may be partially responsible for the high carcinogen susceptibility of LEC rats.

Changes of insulin and glucagon receptors following bile duct ligation and its release

The specific bindings of insulin and glucagon to 4 x 10(4) g pellets containing hepatic plasma membrane were measured at 1 and 2 weeks after bile-duct ligation and 1 week after reduction of jaundice. At 1 week of jaundice, insulin binding was not decreased compared to control rats, however, glucagon binding 30(6)% was significantly lower than that 43(8)% in control rats (p < 0.01). At 2 weeks of jaundice, insulin binding 35(3)% was significantly lower than that 40(5)% in control rats (p < 0.05), and glucagon binding 26(4)% was also significantly lower compared to control rats 42(4)% (p < 0.01). The decreased insulin and glucagon receptors returned to nearly the levels of controls after 1 week's reduction of jaundice. These results suggested that the measurement of receptor binding may be useful as an indicator of the severity of hepatocyte injury.

Diagnostic criteria for neoplastic myoepithelial cells in pleomorphic adenomas and myoepitheliomas. Immunocytochemical detection of muscle-specific actin, cytokeratin 14, vimentin, and glial fibrillary acidic protein

OBJECTIVE

Markers for normal salivary gland myoepithelium were used to determine the extent of their expression in the neoplastic myoepithelial (nonluminal) cells of pleomorphic adenomas and then in the tumor cells in myoepitheliomas and to gather information necessary to establish diagnostic criteria, especially muscle actin expression, for myoepitheliomas.

STUDY DESIGN

Methanol/acetic acid-fixed and paraffin-embedded tissue was used to immunohistochemically study expression of intermediate and smooth-muscle actin filaments in nonluminal cells in 14 pleomorphic adenomas and to compare this to their expression in five myoepitheliomas.

RESULTS

In routine histologic sections, the morphologic variants of nonluminal tumor cells--spindle, stellate, polygonal, angular, and plasmacytoid--in pleomorphic adenoma mirror the spectrum of tumor cells in myoepitheliomas. Immunocytochemical similarities are also apparent. Two specific markers for myoepithelial cells in the normal salivary gland, muscle-specific actin and cytokeratin 14, were both variably, independently, and never uniformly expressed in nonluminal cells of pleomorphic adenoma and tumor cells in myoepitheliomas regardless of their morphology. Cytokeratin 14 in addition labels basal cells of excretory ducts. Both muscle-specific actin and cytokeratin 14 preferentially localized to single layers of periductal cells in pleomorphic adenomas, angular, polygonal, and plasmacytoid cells preferentially expressed cytokeratin 14. Similar patterns were noted in the three myoepitheliomas with reasonable expression of the two markers. Only isolated single cells or small groups of plasmacytoid cells in four pleomorphic adenomas with a significant component of these cells and the two plasmacytoid myoepitheliomas immunostained for muscle-specific actin and cytokeratin 14. In both tumor types, vimentin was nearly uniformly expressed in nonluminal tumor cells of all morphologic types, including plasmacytoid cells.

CONCLUSIONS

The range and transition of morphology of nonluminal cells in pleomorphic adenomas is reflected in myoepitheliomas. Incomplete or absent expression of the myoepithelial/basal cell markers, muscle-specific actin, and cytokeratin 14, and the general expression of vimentin is common to both tumors. Because these findings apply to the majority of plasmacytoid cells in pleomorphic adenomas, tumor cells with a similar morphology and immunoprofile are to be expected in myoepitheliomas; the term plasmacytoid myoepitheliomas is thus appropriate regardless of the presence or absence of muscle-specific actin.

Plasma adrenaline modulates alpha 1-adrenoceptor mediated pressor responses and the baroreflex control in patients with borderline hypertension

Plasma level of adrenaline has been reported to be elevated in borderline hypertension. However, its role in developing and maintaining hypertension is still not completely understood. This study aimed to estimate the role of plasma adrenaline in developing hypertension. Ten patients with borderline hypertension (BHT) and 10 age-matched normotensive subjects were included. We infused at least three graded doses of phenylephrine, an alpha-adrenoceptor agonist, into the antecubital vein of subjects lying quietly in a supine position. Mean blood pressure was measured continuously through the right radial artery. Cardiac output was measured by the thermodilution method before and after the administration of each dose of phenylephrine infusion. We obtained dose-response curves for mean blood pressure and total peripheral resistance to phenylephrine. Baroreflex sensitivity was calculated by plotting the longest R-R intervals against the elevated peak mean blood pressure after the infusion of each dose of phenylephrine. Plasma noradrenaline and adrenaline concentrations at rest were measured by high performance liquid chromatography coupled with trihydroxyindole fluorimetric detection. The plasma adrenaline level at rest was higher in patients with BHT than in normotensive subjects. With graded infusion of phenylephrine, both the pressor responses and the changes in total peripheral resistance were greater in patients with BHT than in normotensive subjects. The plasma adrenaline level was positively correlated with the slope of dose response curves for the increments of mean blood pressure to phenylephrine (r = 0.60, p < 0.01). Baroreflex sensitivity was reduced in patients with BHT as compared with normotensive subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Platelet aggregability and the occurrence of anastomotic leakage after esophageal reconstruction

In 21 patients who had undergone resection and reconstruction for esophageal carcinoma, the postoperative platelet aggregability was measured and the correlation between the occurrence of anastomotic leakage and platelet aggregability was investigated. There was no statistical difference in the clinical features of the patients between those with (n = 5) and without (n = 16) anastomotic leakage. Platelet aggregability was measured by the turbidimetric method from blood samples taken preoperatively, and at 1, 3, and 7 postoperative days (POD). The average values of platelet aggregability in patients without anastomotic leakage were 81.2, 70.4, 80.1, and 81.8%, while those with leakage were 81.3, 47.6, 52.3, 70.6% preoperatively, and 1, 3, and 7 POD, respectively. Thus, platelet aggregability significantly decreased in patients with anastomotic leakage on the first postoperative day (p < .05), and then gradually recovered postoperatively as time passed. Therefore, the measurement of platelet aggregability is considered to be one of the parameters predicting the occurrence of anastomotic leakage, and a prevention in the decrease of platelet aggregability as well as its activation could become a treatment for preventing anastomotic leakage.

[Potential organ donors at an Italian intensive care unit]

AIM

To determine evaluate the number and characteristics of the population diagnosed as being cerebrally dead and the reasons why organs were not donated.

EXPERIMENTAL DESIGN

Retrospective study from 1.1.1990 to 31.5.1994.

SETTING

Intensive care ward at Arezzo Hospital.

PATIENTS

46 patients diagnosed as being cerebrally dead owing to primary intracranial pathology.

RESULTS

Of the 1256 patients admitted to intensive care, 46 were diagnosed as being cerebrally dead. Five became organ donors. The study examines the reasons why the organs of the remaining patients dwere not donated.

CONCLUSIONS

In spite of the fact that the number of donors corpses was broadly in line with national figures (8 per million inhabitants versus 9.7 for the NITp average and 6 for the national average), it is worth underlining the high percentage of patients (26.8%) for whom it was not possible to identify the reasons why the commission for the ascertainment of cerebral death was not summoned. This emphasises the need for greater commitment in the early identification of cerebral death, the monitoring and maintenance of organ functions in potential donors, and likewise the need for increased clarity in the formulation of statutory requirements regarding cerebral death.

Neural invasion in gastric carcinoma

AIMS

To determine whether neural invasion in advanced gastric cancer is of clinicopathological significance.

METHODS

The study population comprised 121 cases of primary advanced gastric carcinoma. Two paraffin wax embedded blocks taken from the central tissue slice in each primary tumour were used. For definitive recognition of neural invasion, immunostaining for S-100 protein was applied to one slide; the other slide was stained with haematoxylin and eosin.

RESULTS

Neural invasion was recognised in 34 of 121 (28%) primary gastric carcinomas. There were significant differences in tumour size, depth of tumour invasion, stage, and curability between patients with and without neural invasion. The five year survival rates of patients with and without neural invasion were 10 and 50%, respectively. Multivariate analysis, however, demonstrated that neural invasion was not an independent prognostic factor.

CONCLUSIONS

Neural invasion could be an additional useful factor for providing information about the malignant potential of gastric carcinoma. This may be analogous to vessel permeation which is thought to be important, but is not an independent prognostic factor.

Acute myeloblastic leukemia associated with an intermediate state between the healthy carrier state and adult T-cell leukemia

This report describes an intermediate state between the human T-cell lymphotropic virus type I (HTLV-I) healthy carrier and adult T-cell Leukemia (ATL) who developed acute myeloblastic leukemia (AML, FAB subtype M2). The polyclonal integration of HTLV-I proviral DNA was demonstrated in the peripheral blood lymphoid cells, whereas AML cells had no HTLV-I proviral DNA. The patient achieved remission after combination chemotherapy but cells with lobulated nuclei persist at a low level and the polyclonal integration of HTLV-I proviral DNA is still demonstrated. We suggest that the patients with the integration of HTLV-I proviral DNA might develop secondary neoplasms more frequently than healthy carriers and this case stresses the need to exercise caution with these patients. The relationship between HTLV-I and AML is briefly discussed.

Changes in IL-6 and IL-8 after hepatectomy in patients with liver cirrhosis

Changes in tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), and interleukin-8 (IL-8) were investigated before and after hepatectomy in patients with or without liver cirrhosis (5 cases without liver cirrhosis and 14 cases with liver cirrhosis). Both the IL-6 and IL-8 values of the cirrhotic patients were significantly higher on the first postoperative day (POD) as compared with the non-cirrhotic patients. Overall, no significant correlation was found between peak values of IL-6 or IL-8 and blood loss or operating time. In the case of the cirrhotic patients, correlation of both IL-6 and IL-8 with operating time was significant at p < 0.05, gamma = 0.534 and 0.586, respectively. No correlation was found between blood loss and the peak value of IL-6, but significant correlation (gamma = 0.647, p < 0.05) was found between them in cirrhotic patients. There was no consistent increase in TNF-alpha and IL-1 beta following hepatectomy. These findings indicate that procedures undertaken to reduce the excessive production of these cytokines may be useful for preventing complications after hepatectomy in cirrhotic patients.

Involvement of spontaneous nitric oxide production in the diabetogenic action of streptozotocin

The exact mechanism by which streptozotocin (STZ) destroys pancreatic beta-cells has not been determined. Recently, nitric oxide was identified as a potent islet toxic compound. However, nitric oxide production by STZ has not been proved yet. In the present studies, we determined whether STZ spontaneously produces nitrite, measured by a spectrophotometric technique based on the Griess reaction. STZ, dissolved in the pH 4.0 citrate buffer, produced significantly more nitrite than that dissolved in pH 7.4. After incubation at 37 degrees C for 120 min, nitrite concentrations were significantly decreased only in STZ dissolved in the pH 7.4 citrate buffer. Following 120 min incubation at 37 degrees C, STZ dissolved at pH 7.4 failed to cause significant islet damage in rats previously deprived of food for 18 h. The present studies demonstrated that STZ may spontaneously produce nitrite in vitro. Nitric oxide production may, at least in part, be responsible for the STZ-induced damage of pancreatic beta-cells of the rodents.

Malignant lymphoma of the rectum treated preoperatively with hyperthermia and radiation

A 58-year-old Japanese woman with primary malignant lymphoma of the rectum was treated preoperatively with radiation and intraluminal hyperthermia, after which abdominoperineal rectal amputation (Miles' operation) was done. The rectal tumor disappeared and there were no lymphoma cells in the resected specimens. The postoperative course was smooth and she is being followed in the outpatient department. At this writing, five years after the surgery, she remains well.

Hepatopancreatoduodenectomy for squamous and adenosquamous carcinoma of the gallbladder

The characteristics of squamous or adenosquamous cell carcinoma of the gallbladder differ quite markedly from those of adenocarcinoma, although the incidence is extremely low. Recently, we encountered both of the former types of gallbladder carcinoma: a 77-year-old man with squamous cell carcinoma and a 70-year-old man with adenosquamous cell carcinoma of the gallbladder. Both had a large mass in the gallbladder fossa region with infiltration to the liver and invasion of the duodenum. Hepatopancreatoduodenectomy was performed on both of these patients. The TNM stage of the former was IV (T4N0M0) and of the latter IV (T4N0M0) and of the latter IV (T4N1bM0). The former has remained well without recurrence for about 1 year and 4 months after the operation, while the latter died of recurrent disease 6 months after operation. The true reason for the difference in the prognosis of these two patients was not known. However, hepatopancreatoduodenectomy is considered to be a most adaptable operative procedure for squamous or adenosquamous cell carcinoma of the gallbladder in view of their mode of spread, and the presence of lymph node metastasis might be a factor of poor prognosis.

Importance of ornithine transcarbamylase (OTC) deficiency in small intestine for urinary orotic acid excretion: analysis of OTC-deficient spf-ash mice with OTC transgene

We report the effect of the ornithine transcarbamylase (OTC) transgene composed of 1.3 kb of the 5' flanking region of the rat OTC gene fused to rat OTC cDNA on urinary orotic acid excretion in OTC-deficient spf-ash (sparse-fur with abnormal skin and hair) mice during overnight-starvation and nitrogen loading. During starvation, spf-ash mice with about 6% and 2% of control levels of OTC activity in the liver and small intestine excreted a large amount of orotic acid in the urine. Transgenic spf-ash mice with about 10% and 30% of the control OTC activities in the liver and small intestine did not excrete more than the normal level of orotic acid. Accidental parasitization of transgenic spf-ash mice with ticks (Myocoptes musculinus) resulted in decrease of the OTC activities in the liver and small intestine to the levels in spf-ash mice, and increased excretion of orotic acid. During extermination of the ticks, the mice showed varied levels of OTC activity and orotic acid excretion. On nitrogen loading, transgenic spf-ash mice as well as spf-ash mice excreted larger amounts of orotic acid, while control mice showed no increase in its excretion. The levels of urinary orotic acid were inversely correlated to the logarithms of the OTC activities in the liver and small intestine, the correlation being significantly higher with intestinal OTC than with hepatic OTC activity. These results suggest that the level of OTC activity in the small intestine is important for production of orotic acid.

Regional differences in cerebral vasomotor control by nitric oxide

Regional differences in the role of nitric oxide in cerebral vasomotor control were investigated with a nitric oxide synthesis inhibitor, NG-monomethyl-L-arginine, or a precursor of nitric oxide, L-arginine using both dog cerebral angiography for the larger artery study and rat isolated arterioles for the microcirculation study. NG-monomethyl-L-arginine (10 mumol) constricted the dog cerebral arteries, by 15.6%, 17.5%, and 27.3% in the middle cerebral, anterior cerebral, and basilar arteries, respectively. The greater constriction of the basilar artery did not reach statistical significance. However, L-arginine (100 mumol) produced significantly greater dilation of basilar arteries than the middle cerebral or anterior cerebral (31.3% vs. 16.7% or 13.1%). NG-monomethyl-L-arginine at 10(-3) M constricted rat arterioles originating from basilar arteries significantly more than the middle cerebral arteries (23% vs. 14%). L-arginine at 10(-3) M dilated rat arterioles from basilar arteries significantly more than from the middle cerebral artery (24 vs. 11%). These findings suggest that the roles of nitric oxide in vasomotor control differs by region in the brain, and it may be greater in vessels of the posterior than of the anterior circulation.

Cytophotometric study of nuclear DNA content in scirrhous gastric carcinoma

We made a cytophotometric DNA analysis using 21 scirrhous gastric carcinomas (SGC), and compared the results with those of 12 undifferentiated type early gastric carcinomas (EGC) located in the gastric body. Nuclear DNA content of tumor cells was measured in the mucosa of SGC (SGCm), serosa of SGC (SGCs) and mucosa of EGC (EGCm). DNA distribution pattern was high ploid in 18 SGCm (86%), 16 SGCs (71%) and 4 EGCm (33%). Mean DNA content was 4.02c in SGCm, 3.91c in SGCs and 3.26c in EGCm. Percentage of tumor cells with a DNA content over 3c was 77.4% in SGCm, 69.1% in SGCs and 49.5% in EGCm. Statistically significant differences in these 3 factors were present between SGCm and EGCm, but absent between SGCm and SGCs. Furthermore, DNA distribution pattern was not different between the mucosa and serosa in 19 SGC (90%). The results suggest that most scirrhous gastric carcinomas are high ploid in origin and do not change their biologic behaviour throughout the tumor progression.

Assignment of CD38, the gene encoding human leukocyte antigen CD38 (ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase), to chromosome 4p15

CD38 has been used as a phenotype marker of lymphocyte differentiation. Recently, we have demonstrated that cyclic ADP-ribose can be synthesized and hydrolyzed by CD38 and acts as a second messenger in insulin secretion from pancreatic beta-cells. We have mapped the CD38 gene to human chromosome 4p15 by fluorescence in situ hybridization.

In vitro induction of cytotoxic T lymphocytes against HTLV-I-infected T-cells from adult T-cell leukemia patients, asymptomatic HTLV-I carriers and seronegative healthy donors

We investigated an in vitro method to produce cytotoxic T lymphocytes (CTLs) against HTLV-I-infected T-cells using peripheral blood mononuclear cells (PBMC) of adult T-cell leukemia (ATL) patients, asymptomatic HTLV-I carriers (AC) and seronegative healthy donors. The PBMC were restimulated repeatedly for 4 weeks with HLA-matched HTLV-I-infected T-cells which had been pretreated at 56 degrees C for 30 min to inactivate infectious HTLV-I. The culture medium included 10-100 units/ml of recombinant lymphokines (rIL-1, rIL-2, rIL-4, rIL-6 and rIL-7) and 10% fetal calf serum in RPMI-1640 medium. The cytotoxic activity was measured against HLA-matched HTLV-I-infected T-cell lines after CD4+ or CD8+ cells were positively panned from the cultured PBMC. The PBMC of ATL, AC and healthy donors were able to produce either CD4+ or CD8+ CTLs against HTLV-I-related antigens (env, gag, p21x, p27rex and p40tax) as well as the antigen(s) of as-yet unknown specificity expressed on HTLV-I-infected T-cells. All the CTLs recognized the specific antigens in the context of either class I or class II HLA types. These results indicated that ATL patients, AC and healthy donors were immunocompetent to generate CTLs against HTLV-I-infected T-cells and probably against HTLV-I-transformed T-cells.

Alpha-melanocyte-stimulating hormone (MSH) inhibits insulin secretion in HIT-T 15 cells

alpha-Melanocyte-stimulating hormone (MSH) antagonizes the binding of interleukin-1 beta (IL-1) to its type I receptors on T cells. IL-1 modulates insulin secretion in the insulin-secreting tumor cell line, HIT-T 15 cells. In the present studies, we examined a hypothesis that alpha-MSH may modulate insulin secretion in HIT-T 15 cells. The addition of alpha-MSH over the concentrations of 10(-10) M inhibited insulin secretion for 4 h. In addition, the carboxyl-terminal tripeptide of alpha-MSH [alpha-MSH(11-13)], which is supposed to be an important sequence of alpha-MSH on its antipyretic effects, significantly inhibited insulin secretion at the concentration of 10(-9) M. In contrast, acetyl-[Nle4,D-Phe7] alpha-MSH(4-10)-amide (10(-11) to 10(-9) M) failed to inhibit insulin secretion. The maximal effect of alpha-MSH on insulin secretion was obtained at the concentration of 10(-9) M. The addition of alpha-MSH from 10(-11) to 10(-9) M significantly inhibited 7.5 mM glucose-stimulated insulin secretion at each period of 0-5, 5-15, and 15-30 min. Radioreceptor assay suggested that HIT-T 15 cells possess the specific binding sites for 125I-labeled alpha-MSH. The present studies indicated that alpha-MSH inhibits insulin secretion through the specific binding site in HIT-T 15 cells.

Successful treatment of a 93-year-old patient with hypoplastic acute monocytic leukemia using macrophage colony-stimulating factor

A 93-year-old patient with hypoplastic acute monocytic leukemia (AMoL) achieved a complete remission after macrophage colony-stimulating factor (M-CSF) therapy. Initially, the patient was treated with a low dose of cytarabine, but this treatment proved ineffective. M-CSF was administered for 14 days by drip intravenous infusion, 800 x 10(4) units per day. After a gradual decrease in the number of leukemic cells, a rapid increase in neutrophils was observed in the peripheral blood, and a bone marrow examination 22 days after discontinuation of M-CSF medication revealed a complete remission. These findings suggest that M-CSF may be useful in treating some elderly patients who have hypoplastic AMoL.