Comparison of early and late start of antihypertensive agents and baroreceptor reflexes

Along with arterial blood pressure reduction, maintenance of the integrity of baroreceptor reflex function contributes to preserving end-organ function in the treatment of hypertensive patients. The purpose of this study was to investigate the effects of antihypertensive agents (trichlormethiazide, atenolol, nicardipine, and enalapril) on baroreceptor reflex function by comparing early and late starts of treatment. We administered each agent to spontaneously hypertensive rats (SHR) as early-start groups from 10 to 36 weeks of age and as late-start groups from 28 to 36 weeks of age. We evaluated the gain of the reflex control of renal sympathetic nerve activity and heart rate using ramp infusions of phenylephrine and nitroglycerin in untreated SHR at 10, 28, or 36 weeks of age and in treated SHR at 36 weeks of age. In 28- and 36-week-old untreated SHR, the renal sympathetic nerve activity gain was not altered and the heart rate gain was decreased (from -2.3 +/- 0.3 to -1.3 +/- 0.3 and -1.2 +/- 0.3 beats per minute [bm]/mm Hg, P < .05, respectively) compared with 10-week-old SHR. Early and late start of therapy produced arterial pressure reductions (-18 +/- 4 and -12 +/- 5 mm Hg, P < .05, respectively). In the early-start groups, the renal sympathetic nerve activity gain was improved markedly in nicardipine- and enalapril-treated SHR (-4.2 +/- 0.2% and -4.9 +/- 0.2% of control/mm Hg, P < .01, respectively), and the heart rate gain was improved markedly in atenolol- and enalapril-treated SHR (-4.1 +/- 0.2 and -4.4 +/- 0.2 bpm/mm Hg, P < .01, respectively). In the late-start groups, the renal sympathetic nerve activity gain was improved moderately in nicardipine- and enalapril-treated SHR (-3.8 +/- 0.2% and -2.9 +/- 0.2% of control/mm Hg, P < .05, respectively). The heart rate gain was improved slightly only in nicardipine-treated SHR (-1.9 +/- 0.2 bpm/mm Hg, P < .05). These results demonstrate that an early start of antihypertensive treatment improves baroreceptor reflex function markedly compared with a late start of treatment. This supports the hypothesis that a possible critical phase sensitive to intervention with antihypertensive treatment exists during the development of hypertension and indicates that the early start of antihypertensive treatment would be required in clinical practice.

[Concurrent high-dose thoracic irradiation plus daily low-dose cisplatin and vindesine in locally advanced unresectable stage III non-small cell lung cancer]

Patients with unresectable non small-cell lung cancer were treated to evaluate the toxicity and efficacy of high-dose thoracic irradiation (RT) combined with concurrent daily cisplatin plus vindesine. Fourteen evaluable patients with unresectable stage III non small-cell lung cancer treated with continuous-course RT (70 Gy in 35 fractions of 2 Gy once daily) and concurrent daily intravenous cisplatin (6 mg/m2) plus vindesine (3 mg/m2 on day 1 and day 8). The objective response rate was 86%, and two patients achieved a radiographic complete response. Leukocytopenia was the severe toxicity, but there were no episodes of discontinuation of treatment. Only one patient had grade 3 acute radiation esophagitis. Ten patients experienced late radiation pneumonitis and nine of those had grade 1 or grade 2. There was only one life-threatening case of toxicity (grade 5 pneumonitis). We concluded that the regimen of high-dose thoracic RT combined with concurrent daily cisplatin plus vindesine obtained a high response rate. Further testing on late toxicities and survival time is required.

Status of patients who underwent uninephrectomy in adulthood more than 20 years ago

We investigated the status of patients without systemic diseases who had undergone uninephrectomy for unilateral renal diseases in adulthood more than 20 years ago at Tokyo Denryoku Hospital. There were 21 participants (mean age +/- SD, 58.6 +/- 8.0 years) who fulfilled these criteria. The average interval since nephrectomy was 27.9 +/- 6.2 years. The mean current creatinine clearance was 88.5 +/- 21.2 mL/min/1.73 m2, which is 92.9% of that in healthy age- and sex-matched controls with two kidneys. The 24-hour urine protein excretion in these patients was only slightly higher than in the controls (214 +/- 190 mg v 119 +/- 62 mg, P = NS). Age at nephrectomy, length of time with a single kidney, or sex had little effect on the remnant renal functions. There was a positive correlation between current mean arterial pressure and serum creatinine (r = 0.44, P < 0.05). Patients who developed hypertension after uninephrectomy had a family history of hypertension more frequently than those with normotension (86% v 29%, P < 0.05). We conclude that (1) renal function after compensatory hyperfiltration of more than 20 years due to uninephrectomy for unilateral renal diseases in adulthood is well maintained, although hypertension has a considerable effect on the renal functions, and that (2) family history of hypertension plays a key role in determining the incidence of hypertension even in the uninephrectomized patients.

Baroreceptor function is restored by antihypertensive therapy through lowering of blood pressure in adult SHR

1. We investigated the effects of antihypertensive treatment (8 weeks) with four different agents (trichlormethiazide, atenolol, nicardipine and enalapril) on baroreceptor function in 28 week old spontaneously hypertensive rats (SHR) to measure aortic depressor nerve (ADN) activity. 2. Threshold pressure (Pth) of ADN activity was elevated and the gain sensitivity of the pressure-activity curve, as determined by the maximum gain (Gmax) of a logistic function curve, was depressed in untreated SHR compared to those in untreated Wistar-Kyoto (WKY) rats. 3. Treatment with the four agents similarly reduced blood pressure in SHR. Each of the four agents induced a decrease in Pth and an increase in Gmax to a similar extent in SHR. 4. These findings suggest that antihypertensive therapy in chronic hypertension augments baroreceptor function through the lowering of blood pressure but not through specific pharmacological actions.

TNF inhibitor with a low molecular weight found in the human sera

We found a TNF inhibitory factor with a molecular weight of 5 to 10 kDa in the human sera. The activity was detected by inhibiting the activity of serum to TNF-induced cytotoxicity against target cells. It was found in sera of all the healthy donors tested without any febrile diseases. Moreover, our results demonstrated that TNF inhibitory factor decreases in the semum of patients on regular hemodialysis treatment and in the serum of diabetes mellitus patients. The activity found in human sera was eluted from DEAE-cellulose column (Mono Q) at 0.25 and 0.45 M NaCl, and was labile to incubation for 60 min at 56 degrees C and susceptible to treatment with trypsin, which destroyed 60% of its biological activity. TNF inhibitory factor may act as a regulator of the biological activity of TNF and could have beneficial effects in certain inflammatory conditions, and therefore, could be useful in clinical application.

Differential modulation of baroreceptor sensitivity by long-term antihypertensive treatment

We investigated the effects of long-term oral treatment with four different classes of antihypertensive drugs (a thiazide diuretic [trichlormethiazide, 10 mg/kg per day]; a beta-blocker [atenolol, 90 mg/kg per day]; a calcium channel antagonist [nicardipine, 150 mg/kg per day]; and an angiotensin-converting enzyme inhibitor [enalapril maleate, 10 mg/kg per day]) on aortic baroreceptor activity in spontaneously hypertensive rats with chronic hypertension (36 weeks of age). Treatment with each of the four drugs, given from 10 to 36 weeks of age, similarly decreased arterial pressure (171 +/- 2 to 144 +/- 1 mm Hg, P < .01) and similarly decreased the threshold pressure for baroreceptors (116 +/- 3 to 103 +/- 1 mm Hg, P < .05). The four antihypertensive drugs also potentiated the maximal gain of the pressure-activity relation in these rats (untreated, 1.08 +/- 0.05% maximum/mm Hg); however, nicardipine and enalapril (1.77 +/- 0.04% and 1.70 +/- 0.06% maximum/mm Hg, respectively) augmented the maximal gain to a greater extent (P < .05 to .01) than did trichlormethiazide or atenolol (1.49 +/- 0.05% and 1.42 +/- 0.02% maximum/mm Hg, respectively). When the initiation of treatment was delayed to 28 weeks of age, no differences were found in the effects on either threshold pressure (104 +/- 1 mm Hg) or maximal gain (1.36 +/- 0.03% maximum/mm Hg) for all four drugs.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of preoperative chemotherapy on gastric carcinoma: the relationship between histopathologic response and prognosis

To evaluate the efficacy of preoperative chemotherapy in the treatment of gastric carcinoma, 48 previously untreated patients with locoregional advanced gastric carcinoma were consecutively enrolled in this study and received preoperative 5-fluorouracil (5-FU) or 5'-deoxy-5- fluorouridine (5'-DFUR). Histopathologically, 17 patients showed no response, 27 responded slightly, 3 moderately, and 1 had an excellent response to the chemotherapy. Based on clinical cancer staging, the overall 5-year survival rate was 79% in patients with stages IB and II cancer, 44% in patients with stage III cancer, and 14% in those with stage IV cancer. In patients with stages IB, II, and IIIA disease, the 5-year survival rate for those with a positive histopathologic response to the chemotherapy was 74%, whereas that for the nonresponders was 45%. No relationship was seen between the grade of the histopathologic response and the 5-year survival rate of patients with stage IIIB and IV carcinoma. In a second group of 27 patients who received preoperative chemotherapy with 5-FU, the effect of 5-FU was evaluated using thymidylate synthetase (TS) inhibition. Free TS and total TS were measured in the tumor samples, and the thymidylate synthetase inhibition rate (TSIR) was calculated. TSIR ranged from 0% to 90.7%. The mean TSIR was 66.2% in patients with a positive histopathologic response to chemotherapy and 30.3% in those with a negative response. Mild chemotherapy as orally administered 5-FU or 5'-DFUR was found to be useful in patients with resectable gastric cancer. Furthermore, a correlation was found in chemosensitivity, histopathologic response, and TSIR.

Reduced expression of c-Fos in female NOD mouse thymocytes and up-regulation with human lymphotoxin

Previously we reported that the administration of human (h) lymphotoxin (h-LT) markedly protected NOD mice from insulin-dependent diabetes mellitus (IDDM) partly by affecting the generation phase of anti-islet effector cells, probably in the thymus. In this study, we investigated the effect of h-LT on the signal transduction of the mouse thymocytes by observing c-Fos expression in the thymocytes by using a flow cytometer. The intensity of c-Fos expression in whole thymocytes was significantly lower in the female NOD with a high incidence of diabetes than that in the male NOD mice with a low incidence of diabetes and than that in normal mice (P < 0.0001). The low c-Fos expression in the female NOD thymocytes was most prominent in CD3low thymocytes. c-Jun expression of the CD3low thymocytes was also lower in the female NOD mice. Administrations of h-LT, h-TNF, and h-IL-2, which has been reported to prevent IDDM in NOD mice by systemic administration, significantly up-regulated c-Fos expression in CD3low thymocytes. From these results, it is assumed that a relationship may exist between the high diabetes incidence and the defective c-Fos expression in female NOD mice and between the prevention of IDDM and the amelioration of the defective c-Fos expression with h-LT in female NOD mice.

[Effect of ulinastatin on the free radical during cardiopulmonary bypass]

Cardiopulmonary bypass (CPB) involves many factors for generating free radicals. It is difficult to detect free radical directly in clinical situations. Vitamin E is recognized as an intrinsic radical scavenger. We examined the change of vitamin E level to prove indirectly the evidence of free radical generation during CPB. Moreover, we investigated the effect of ulinastatin on the free radical during CPB by determining the vitamin E level. Twenty patients who received cardiac surgery were divided into the membrane oxygenator group and the bubble oxygenator group. In each group, five patients received 12,000 units.kg-1 of ulinastatin 15 min after starting CPB. Blood samples were obtained 15 min after starting CPB and 15 min after reperfusion of coronary artery. In the bubble oxygenator group without ulinastatin, vitamin E level at reperfusion phase decreased significantly compared with that at the start of CPB. In the bubble oxygenator group with ulinastatin, vitamin E level at reperfusion phase showed no decrease compared with the level at the start of CPB. In the membrane oxygenator group, there was no significant change in vitamin E level. Therefore, we suspect that a decrease of vitamin E during CPB with bubble oxygenator demonstrates the evidence of free radical generation and these results suggest that ulinastatin may scavenge free radicals during CPB.

[An autopsy case of a severely handicapped woman with subependymoma in infancy and multiple meningiomas in adulthood: problems of using radiation therapy for brain tumors in infancy]

We present an autopsy case of a severely handicapped 21-year-old woman. A subependymoma that was pathologically confirmed by biopsy was found at the age of 6 months, and radiation therapy was administered at 1 year. Thereafter, she developed severe growth retardation, spastic quadriplegia, profound mental retardation and intractable epilepsy. The patient died of acute cardiovascular failure at the age of 21. Unexpectedly, at autopsy more than 20 multiple meningiomas were found intracranially. Such a large number of meningiomas is rare, even though they might be induced by radiation. This case warns us of the use of radiotherapy for brain tumors in infancy, and points to the necessity of following such patients with radioimaging to detect radiation-induced brain tumors in an early stage.

Cytotoxic NK1.1 Ag+ alpha beta T cells with intermediate TCR induced in the liver of mice by IL-12

Systemic administration of IL-12 greatly reduced the hepatic metastases of i.v.-injected liver metastatic EL4 tumor cells in C57BL/6 +/+ and nu/nu mice. Cytotoxic assay in vitro revealed that administration of IL-12 greatly enhanced cytotoxicity of hepatic mononuclear cells (MNC) against various NK- sensitive and -resistant tumor targets, including EL4 cells, whereas only slight or moderate augmentation of the cytotoxicity was observed in splenocytes in normal and nude mice. After IL-12 administration, hepatic MNC increased in number and showed vigorous proliferation in vitro. Hepatic MNC of control C57BL/6 +/+ mice contain alpha beta T cells with intermediate TCR (TCRint) as well as alpha beta T cells with bright TCR, whereas hepatic MNC of nu/nu mice have only TCRint cells. These TCRint cells are found to be NK1.1 Ag+ (NK1+ TCRint). Systemic administration of IL-12 into normal and nude mice markedly augments the NK1 expression of NK1+ TCRint cells (NK1high TCRint), which is comparable to or brighter than that of NK cells in the liver, whereas alpha beta T cells with bright TCR or gamma delta T cells in the liver are NK1-. Depletion of either NK1.1+ or CD3+ cells, but not CD8+ cells, of hepatic MNC from IL-12-treated normal mice by respective Abs and C in vitro abrogate their cytotoxicity. These results revealed that TCRint cells are potent cytotoxic effector cells and suggest that NK1high TCRint cells are the main antimetastatic population in the liver, and that TCRint cells are functionally different from regular T cells with bright TCR.

[Non-Hodgkin's lymphoma presenting as a soft tissue tumor in the connective tissue at the thigh]

A 62-year-old man visited our hospital in July 1993, because of a right thigh mass which had grown gradually since two years previously. Physical examination revealed that the mass at the right thigh region, was elastic soft and about 15 x 10 cm in diameter, without regional lymph node swelling. An ultrasound study showed a hypoechogenic and mesh patterned mass. MRI revealed that the tumor was well defined from subcutaneous adipose tissue and skeletal muscle, indicating that it arose in connective tissue. Angiography demonstrated diffuse hypervascularization of the tumor, and Gallium scintigraphy showed remarkable accumulation at the tumor. Serum IgM was increased, which was proven to be an monoclonal hypergammopathy (IgM, lambda). Histological examination of a biopsied specimen obtained from the thigh mass revealed B cell lymphoma, lymphoplasmacytic cell type. The patient achieved a complete remission after surgical treatment following radiation and combination chemotherapy.

Cytotoxic NK1.1 Ag+ alpha beta T cells with intermediate TCR induced in the liver of mice by IL-12

Systemic administration of IL-12 greatly reduced the hepatic metastases of i.v.-injected liver metastatic EL4 tumor cells in C57BL/6 +/+ and nu/nu mice. Cytotoxic assay in vitro revealed that administration of IL-12 greatly enhanced cytotoxicity of hepatic mononuclear cells (MNC) against various NK- sensitive and -resistant tumor targets, including EL4 cells, whereas only slight or moderate augmentation of the cytotoxicity was observed in splenocytes in normal and nude mice. After IL-12 administration, hepatic MNC increased in number and showed vigorous proliferation in vitro. Hepatic MNC of control C57BL/6 +/+ mice contain alpha beta T cells with intermediate TCR (TCRint) as well as alpha beta T cells with bright TCR, whereas hepatic MNC of nu/nu mice have only TCRint cells. These TCRint cells are found to be NK1.1 Ag+ (NK1+ TCRint). Systemic administration of IL-12 into normal and nude mice markedly augments the NK1 expression of NK1+ TCRint cells (NK1high TCRint), which is comparable to or brighter than that of NK cells in the liver, whereas alpha beta T cells with bright TCR or gamma delta T cells in the liver are NK1-. Depletion of either NK1.1+ or CD3+ cells, but not CD8+ cells, of hepatic MNC from IL-12-treated normal mice by respective Abs and C in vitro abrogate their cytotoxicity. These results revealed that TCRint cells are potent cytotoxic effector cells and suggest that NK1high TCRint cells are the main antimetastatic population in the liver, and that TCRint cells are functionally different from regular T cells with bright TCR.

Effects of macrophage depletion on the induction of histidine decarboxylase by lipopolysaccharide, interleukin 1 and tumour necrosis factor

1. Our previous work has shown that injection into mice of lipopolysaccharide (LPS) and the cytokines interleukin 1 (IL-1) and tumour necrosis factor (TNF) induces histidine decarboxylase (HDC), the enzyme forming histamine, in various tissues such as liver, lung, spleen and bone marrow, but not in the blood. The induction of HDC also occurs in nude mice and mast cell-deficient mice. On the other hand, haematopoietic cytokines such as IL-3, granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage CSF (GM-CSF) only induce HDC in the haematopoietic organs, i.e. bone marrow and spleen. In the present study, the effect of macrophage depletion on the induction of HDC was examined. 2. On day 1 after a single intravenous injection of a macrophage depletor (liposomes encapsulating dichloromethylene diphosphonate, which is toxic when ingested into macrophages), macrophages were almost completely depleted in the liver and reduced by about 50% in the spleen and bone marrow, but not significantly affected in the lung. On day 3, the degrees of the depletion were similar to those of day 1. In the spleen, macrophages were depleted in the red pulp, and there was a structural destruction. 3. In macrophage-depleted mice, the induction of HDC by LPS, IL-1 alpha or TNF-alpha was not impaired in the liver, and was potentiated in the lung and bone marrow. The induction of HDC was decreased only in the spleen at day 3. 4. HDC was not induced by LPS in the spleen of the adult rat, which is correspondingly inactive in haematopoiesis.5 These results indicate that the major cells in which HDC activity is induced in response to LPS, IL-1 and TNF are not circulating granulocytes, circulating monocytes, T cells derived from thymus, mast cells or phagocytic macrophages. Based on these results, we discuss the possibility that the major cells in which HDC was induced in non-haematopoietic and haematopoietic organs were endothelial cells and haematopoietic precursor cells respectively.

Cervical cytology and conservative management of cervical neoplasias during pregnancy

To elucidate the clinical significance of cervical cytology during pregnancy, 7,725 pregnant women were examined. Abnormal cytologic findings were recorded in 65 cases (0.8%). Colposcopically directed punch biopsies revealed cervical dysplasia and carcinoma in 27 cases (0.35%). The incidences in a massive examination for 714,119 women in Osaka Prefecture were 1.1% and 0.25%, respectively. Cytologic findings of the patients with cervical neoplasia during pregnancy agreed well (76%) with their histologic findings. Colposcopically, the squamo-columnar junction was visible in many cases, and white epithelium was most commonly observed during pregnancy. Pre- and postpartum follow-up study revealed that progression from dysplasia was seen only in two (20%) of 20 cases. Laser conization was performed on six women during pregnancy, and four were microinvasive carcinoma, all of which underwent normal vaginal delivery without any complication from conization. These results suggest that routine cervical cytology must be performed during pregnancy, and cytologic and colposcopic diagnosis may supply enough data to avoid unnecessary biopsies. Moreover, laser conization is recommended as an excellent diagnostic and therapeutic procedure for women with microinvasive carcinoma during pregnancy.

Different responses of renal blood flow and sympathetic nerve activity to captopril and nicardipine in conscious renal hypertensive rabbits

To elucidate the roles of endogenous angiotensin II (AII) and renal sympathetic nerve activity (RSNA) in modulation of renal blood flow (RBF), we recorded RBF and RSNA in conscious two-kidney, one-clip (2K1C) hypertensive rabbits with blood pressure (BP) reduced to a similar extent by captopril (5 mg/kg) and nicardipine (4.3 micrograms/kg/min). We measured plasma concentrations of AII, arginine vasopressin (AVP), and norepinephrine (NE). Despite comparable depressor effects, changes in RBF showed different profiles with the two drugs in renal hypertensive rabbits. After captopril injection, RBF was consistently increased to 143 +/- 7%. In contrast, with nicardipine infusion, RBF was initially increased to 114 +/- 5% and then significantly decreased to 86 +/- 4%. The increase in RSNA was greater with captopril than with nicardipine. Plasma concentration of AII was decreased with captopril but significantly increased with nicardipine. In sham-clipped normotensive rabbits in which plasma AII was not increased, RBF was not reduced with nicardipine. Thus, vasoconstrictor actions of RSNA and increased AII may have overcome the vasodilatory effect of nicardipine in conscious renal hypertensive rabbits. Because the increase in RSNA was smaller with nicardipine, we speculate that the vasoconstriction induced by AII, as well as background BP level, played a substantial role in determining RBF.

Role of nitric oxide in regulation of baroreceptor reflex

The possible role of nitric oxide (NO) on modulating sympathetic nerve activity through its action on baroreceptor reflex arc was investigated. L-Arginine, a precursor of NO, and NG-monomethyl-L-arginine (L-NMMA), an inhibitor of NO synthase, were separately infused intravenously in increasing doses in 126 pentobarbital-anesthetized rabbits. Mean arterial pressure (MAP), heart rate (HR), aortic nerve activity (ANA), cervical (CSNA) and renal sympathetic nerve activities (RSNA) were recorded. L-Arginine infusion decreased MAP (P < 0.05), ANA (P < 0.05), CSNA (P < 0.05) and RSNA (P < 0.05) without changes in HR. Infusion of D-arginine, an enantiomer of L-arginine, and simultaneous infusion of L-arginine and L-NMMA, did not elicit such changes. L-NMMA infusion increased MAP (P < 0.05) and ANA (P < 0.05) and decreased HR (P < 0.05), while it tended to increase CSNA and RSNA without significance. Infusion of L-arginine or L-NMMA did not alter the slope of ANA, CSNA, RSNA, or HR in relation to MAP. These results suggest that NO modulates efferent sympathetic nerve activity, not by altering the afferent or efferent limbs of the baroreceptor reflex arc, but by interacting with the sympathetic pathway in the central nervous system.