Pneumothorax associated with nontuberculous mycobacteria: A retrospective study of 69 patients

The incidence of nontuberculous mycobacterial pulmonary disease (NTMPD) is increasing worldwide. Secondary spontaneous pneumothorax occurs as a complication of underlying lung disease and is associated with higher morbidity, mortality, and recurrence than primary spontaneous pneumothorax. We here investigated the clinical features and long-term outcomes of pneumothorax associated with NTMPD.We conducted a retrospective study on consecutive adult patients with pneumothorax associated with NTMPD at Fukujuji Hospital and Keio University Hospital from January 1992 to December 2013. We reviewed the medical records of 69 such patients to obtain clinical characteristics, radiological findings, and long-term outcomes, including pneumothorax recurrence and mortality.The median age of the patients was 68 years; 34 patients were women. The median body mass index was 16.8 kg/m. Underlying pulmonary diseases mainly included chronic obstructive pulmonary disease and pulmonary tuberculosis. On computed tomography, nodules and bronchiectasis were observed in 46 (98%) and 45 (96%) patients, respectively. Consolidation, pleural thickening, interlobular septal thickening, and cavities were most common, and observed in 40 (85%), 40 (85%), 37 (79%), and 36 (77%) patients, respectively. Regarding pneumothorax treatment outcomes, complete and incomplete lung expansion were observed in 49 patients (71%) and 15 patients (22%), respectively. The survival rate after pneumothorax was 48% at 5 years. By the end of the follow-up, 33 patients had died, and the median survival was 4.4 years with a median follow-up period of 1.7 years. The rate of absence of recurrence after the first pneumothorax was 59% at 3 years. By the end of the follow-up, 18 patients had experienced pneumothorax recurrence. Furthermore, 12/18 patients (66%) with recurrent pneumothorax died during the study period. Twenty-three patients (70%) died because of NTMPD progression. Low body mass index (BMI) was a negative prognostic factor for pneumothorax associated with NTMPD in multivariate analysis (HR 0.79, 95% CI 0.64-0.96; P = 0.018)Patients with pneumothorax associated with NTMPD have advanced disease, a high rate of pneumothorax recurrence, and poor prognosis, regardless of the pneumothorax treatment used. Further improvements in early diagnosis of NTMPD and appropriate management in both NTMPD and NTMPD-associated pneumothorax are needed.

Association of IL28B variants with response to pegylated-interferon alpha plus ribavirin combination therapy reveals intersubgenotypic differences between genotypes 2a and 2b

Genetic polymorphisms of the interleukin 28B (IL28B) locus are associated closely with outcomes of pegylated-interferon (PEG-IFN) plus ribavirin (RBV) combination therapy. The aim of this study was to investigate the relationship between IL28B polymorphism and responses to therapy in patients infected with genotype 2. One hundred twenty-nine chronic hepatitis C patients infected with genotype 2, 77 patients with genotype 2a and 52 patients with genotype 2b, were analyzed. Clinical and laboratory parameters, including genetic variation near the IL28B gene (rs8099917), were assessed. Drug adherence was monitored in each patient. Univariate and multivariate statistical analyses of these parameters and clinical responses were carried out. Univariate analyses showed that a sustained virological response was correlated significantly with IL28B polymorphism, as well as age, white blood cell and neutrophil counts, adherence to RBV, and rapid virological response. Subgroup analysis revealed that patients infected with genotype 2b achieved significantly lower rapid virological response rates than those with genotype 2a. Patients with the IL28B-major allele showed higher virus clearance rates at each time point than those with the IL28B-minor allele, and the differences were more profound in patients infected with genotype 2b than those with genotype 2a. Furthermore, both rapid and sustained virological responses were associated significantly with IL28B alleles in patients with genotype 2b. IL28B polymorphism was predictive of PEG-IFN plus RBV combination treatment outcomes in patients infected with genotype 2 and, especially, with genotype 2b. In conclusion, IL-28B polymorphism affects responses to PEG-IFN-based treatment in difficult-to-treat HCV patients.

Cholestatic liver fibrosis and toxin-induced fibrosis are exacerbated in matrix metalloproteinase-2 deficient mice

Matrix metalloproteinase (MMP) plays an important role in homeostatic regulation of the extracellular environment and degradation of matrix. During liver fibrosis, several MMPs, including MMP-2, are up-regulated in activated hepatic stellate cells, which are responsible for exacerbation of liver cirrhosis. However, it remains unclear how loss of MMP-2 influences molecular dynamics associated with fibrogenesis in the liver. To explore the role of MMP-2 in hepatic fibrogenesis, we employed two fibrosis models in mice; toxin (carbon tetrachloride, CCl4)-induced and cholestasis-induced fibrosis. In the chronic CCl4 administration model, MMP-2 deficient mice exhibited extensive liver fibrosis as compared with wild-type mice. Several molecules related to activation of hepatic stellate cells were up-regulated in MMP-2 deficient liver, suggesting that myofibroblastic change of hepatic stellate cells was promoted in MMP-2 deficient liver. In the cholestasis model, fibrosis in MMP-2 deficient liver was also accelerated as compared with wild type liver. Production of tissue inhibitor of metalloproteinase 1 increased in MMP-2 deficient liver in both models, while transforming growth factor β, platelet-derived growth factor receptor and MMP-14 were up-regulated only in the CCl4 model. Our study demonstrated, using 2 experimental murine models, that loss of MMP-2 exacerbates liver fibrosis, and suggested that MMP-2 suppresses tissue inhibitor of metalloproteinase 1 up-regulation during liver fibrosis.

Mutations in the interferon sensitivity determining region and virological response to combination therapy with pegylated-interferon alpha 2b plus ribavirin in patients with chronic hepatitis C-1b infection

BACKGROUND

Pegylated-interferon-alpha 2b (PEG-IFN) plus ribavirin (RBV) therapy is currently the de-facto standard treatment for hepatitis C virus (HCV) infection. The aims of this study were to analyze the clinical and virological factors associated with a higher rate of response in patients with HCV genotype 1b infection treated with combination therapy.

METHODS

We analyzed, retrospectively, 239 patients with chronic hepatitis C-1b infection who received 48 weeks of combination therapy. We assessed clinical and laboratory parameters, including age, gender, pretreatment hemoglobin, platelet counts, HCV RNA titer, liver histology, the number of interferon sensitivity determining region (ISDR) mutations and substitutions of the core amino acids 70 and 91. Drug adherence was monitored in each patient. We carried out univariate and multivariate statistical analyses of these parameters and clinical responses.

RESULTS

On an intention-to-treat (ITT) analysis, 98 of the 239 patients (41%) had sustained virological responses (SVRs). Patients with more than two mutations in the ISDR had significantly higher SVR rates (P<0.01). Univariate analyses showed that stage of fibrosis, hemoglobin, platelet counts, ISDR mutations, serum HCV RNA level, and adherence to PEG-IFN plus RBV were significantly correlated with SVR rates. Multivariate analysis in subjects with good drug adherence extracted the number of ISDR mutations (two or more: odds ratio [OR] 5.181).

CONCLUSIONS

The number of mutations in the ISDR sequence of HCV-1b (>or=2) is the most effective parameter predicting a favorable clinical outcome of 48-week PEG-IFN plus RBV therapy in patients with HCV genotype 1b infection.

Comparison of HCV-associated gene expression and cell signaling pathways in cells with or without HCV replicon and in replicon-cured cells

BACKGROUND

Hepatitis C virus (HCV) replication is affected by several host factors. Here, we screened host genes and molecular pathways that are involved in HCV replication by comprehensive analyses using two genotypes of HCV replicon-expressing cells, their cured cells and naïve Huh7 cells.

METHODS

Huh7 cell lines that stably expressed HCV genotype 1b or 2a replicon were used. The cured cells were established by treating HCV replicon cells with interferon-alpha. Expression of 54,675 cellular genes was analyzed by GeneChip DNA microarray. The data were analyzed by using the KEGG Pathway database.

RESULTS

Hierarchical clustering analysis showed that the gene-expression profiles of each cell group constituted clear clusters of naïve, HCV replicon-expressed, and cured cell lines. The pathway process analysis between the replicon-expressing and the cured cell lines identified significantly altered pathways, including MAPK, steroid biosynthesis and TGF-beta signaling pathways, suggesting that these pathways were affected directly by HCV replication. Comparison of cured and naïve Huh7 cells identified pathways, including steroid biosynthesis and sphingolipid metabolism, suggesting that these pathways were required for efficient HCV replication. Cytoplasmic lipid droplets were obviously increased in replicon-expressing and cured cells as compared to naïve cells. HCV replication was significantly suppressed by peroxisome proliferator-activated receptor (PPAR)-alpha agonists but augmented by PPAR-gamma agonists.

CONCLUSION

Comprehensive gene expression and pathway analyses show that lipid biosynthesis pathways are crucial to support proficient virus replication. These metabolic pathways could constitute novel antiviral targets against HCV.

Antiviral effects of the interferon-induced protein guanylate binding protein 1 and its interaction with the hepatitis C virus NS5B protein

Interferons (IFNs) and the interferon-stimulated genes (ISGs) play a central role in antiviral responses against hepatitis C virus (HCV) infection. We have reported previously that ISGs, including guanylate binding protein 1 (GBP-1), interferon alpha inducible protein (IFI)-6-16, and IFI-27, inhibit HCV subgenomic replication. In this study we investigated the effects of these ISGs against HCV in cell culture and their direct molecular interaction with viral proteins. HCV replication and virus production were suppressed significantly by overexpression of GBP-1, IFI-6-16, or IFI-27. Knockdown of the individual ISGs enhanced HCV RNA replication markedly. A two-hybrid panel of molecular interaction of the ISGs with HCV proteins showed that GBP-1 bound HCV-NS5B directly. A protein truncation assay showed that the guanine binding domain of GBP-1 and the finger domain of NS5B were involved in the interaction. Binding of NS5B with GBP-1 inhibited its guanosine triphosphatase GTPase activity, which is essential for its antiviral effect. Taken together, interferon-induced GBP-1 showed antiviral activity against HCV replication.

CONCLUSION

Binding of the HCV-NS5B protein to GBP-1 countered the antiviral effect by inhibition of its GTPase activity. These mechanisms may contribute to resistance to innate, IFN-mediated antiviral defense and to the clinical persistence of HCV infection.

A female-specific desaturase gene responsible for diene hydrocarbon biosynthesis and courtship behaviour in Drosophila melanogaster

Drosophila melanogaster shows sexually dimorphic cuticular hydrocarbons, with monoenes produced in males and dienes produced in females. Here we describe a female-specific desaturase gene, desatF. RNAi knock-down led to a dramatic decrease in female dienes and increase in monoenes paralleled with an increase in copulation latency and a decrease in courtship index and copulation attempts by the males. The desatF gene was also expressed in females from D. sechellia, rich in dienes, but not D. simulans, which produce only monoenes. When hydrocarbons were feminized in D. melanogaster males by targeted expression of the transformer gene, the expression of desatF occurred. These results strongly suggest that desatF is a crucial enzyme for female pheromone biosynthesis and courtship behaviour in D. melanogaster.

Effect of human hydrosalpinx fluid on in vitro mouse embryogenesis

OBJECTIVE

Women with hydrosalpinx have an unfavorable pregnancy rate. As one approach to elucidate the effect of hydrosalpinx on uterine tubal functioning, we examined the effect of hydrosalpinx fluid on early embryo development in mice.

METHODS

Hyperovulation was induced in ICR mice, and late 2-cell-stage embryos were harvested 42 hours after administration of human chorionic gonadotropin (hCG). Hydrosalpinx fluid was obtained from patients during surgery after informed consent was obtained. The embryos were cultured in 3 culture fluids: (1) mBWW medium containing 0.3% bovine serum albumin (positive-control medium) (BSA), (2) Ca2+, Mg2+-free phosphate buffered saline (negative-control medium) (PBS), and (3) 100% human hydrosalpinx fluid. The developmental status of the embryos 120 hours after hCG administration was examined.

RESULTS

Embryogenesis from a 2-cell-stage embryo to a blastocyst was observed in 98.3% (118/120) of the embryos cultured in the mBWW medium, in 0% (0/120) of the embryos cultured in PBS, and in 98.3% (118/120) of the embryos cultured in 100% human hydrosalpinx fluid.

CONCLUSION

In the micro-environment of human hydrosalpinx fluid, late 2-cell embryos of ICR mice developed normally to blastocysts. The present results also suggest that non-species-specific embryogenetic factors might be present in human hydrosalpinx fluid.

Cardioprotective effects of quinapril after myocardial infarction in hypertensive rats

Although angiotensin-converting enzyme inhibitors are beneficial for patients with congestive heart failure, the appropriate timing and dosage in acute myocardial infarction are still controversial. We examined the hemodynamic effects of quinapril administered before acute myocardial infarction in spontaneously hypertensive rats (SHR). Quinapril (10 mg/kg per day in drinking water) was started 1 week before infarction and continued for 4 weeks after infarction (total duration 5 weeks). The hemodynamic parameters were evaluated by cardiac catheterization 4 weeks after coronary ligation. Sham-operated SHR served as controls. After infarction, left ventricular end-diastolic and right atrial pressures were increased (P < 0.01) and blood pressure and cardiac index were decreased (P < 0.01); the magnitude of blood pressure reduction was similar in the treated and untreated rats with infarction. Quinapril improved these hemodynamic parameters significantly and decreased left and right ventricular weight. These results suggest that a prior treatment with quinapril in SHR with acute myocardial infarction is hemodynamically beneficial.

Ovulation and the suppression of mating in Drosophila melanogaster females: behavioral basis

Virgin females of Drosophila melanogaster that are ectopically expressing the sex-peptide gene show a high level of ovulation and are unreceptive to males. However, if they are genetically deprived of eggs, receptivity is considerably restored (Fuyama, 1995). These females, whether they have eggs or not, extrude their ovipositors toward courting males as frequently as do fertilized females. However, this rejection behavior was ineffective in suppressing male courtship. Of females with eggs, about half of them could suppress male courtship. Females lacking eggs could not suppress male courtship and continued to elicit vigorous courtship. This difference seems to account for the increased mating frequency in sterilized females. Courtship behavior by mutant males defective in olfaction or learning suggested that females are capable of repelling males by emitting a volatile pheromone(s) with an inhibitory effect on male courtship.

[Internal carotid artery occlusion related to seat belt shoulder strap: report of two cases]

Two cases of traumatic internal carotid artery occlusion probably related to the seat belt shoulder strap are reported. Case 1. A 20-year-old woman was driving and was struck on the right front side of her car by another car. There were neither bruises, abrasions on her neck, nor weakness in her extremities. About 4 hours later, she developed left hemiplegia, and CT scan taken on the following day revealed low density areas in the capsulostriatal area on the right. The right carotid angiography revealed occlusion of the internal carotid artery about 3 cm distal to the bifurcation. Case 2. A 43-year-old man was driving and was struck on the front of his car by a hard iron railing. He sustained a sternum fracture, but there was no disturbance of consciousness or paresis of the extremities. His neck was unremarkable externally. About 50 days later, he developed left hemiplegia. CT scan and MRI revealed a massive infarction in the distribution of the right middle cerebral artery territories. The carotid angiography revealed occlusion of the right internal carotid artery about 3 cm distal to the bifurcation. In each cases, the driver was wearing a three-point shoulder seatbelt when the car was struck on the front or on the right front. Previous experimental studies have revealed in these situations the neck is flexed right anteriorly, and then quickly overextended left posteriorly. The overextension of the neck probably injured the intima of the internal carotid artery ipsilateral to the shoulder fixed in the seatbelt, resulting in the subsequent occlusion by a thrombus.

Comparable effects of angiotensin II and converting enzyme blockade on hemodynamics and cardiac hypertrophy in spontaneously hypertensive rats

Angiotensin-converting enzyme inhibitors may regress left ventricular hypertrophy (LVH) without decreasing blood pressure (BP). The aim of the present study was to compare the effects of low and high doses of lisinopril and the angiotensin II receptor antagonist TCV116 (TCV) on LVH and hemodynamics in spontaneously hypertensive rats (SHR). Lisinopril (0.5 and 3 mg/kg per day) and TCV (0.3 mg/kg per day) were given to 8-week-old male SHR daily for 2 weeks. Untreated SHR and Wistar-Kyoto rats (WKY) served as controls. Untreated SHR had a greater left ventricular (LV) weight than WKY (p < 0.01). Lisinopril (3 mg/kg per day) decreased both LV weight and BP. Lisinopril (0.5 mg/kg per day) significantly decreased LV weight, but not BP. In contrast, although TCV significantly decreased BP, LVH was not suppressed. Renal blood flow (RBF) in untreated SHR was less than that in WKY (p < 0.05), but was increased with either lisinopril (3 mg/kg per day)-treated rats (p< 0.05). These findings suggest that factors other than afterload reduction play a role in the regression of LVH with lisinopril, whereas a longer duration of treatment and/or a higher dose may be necessary with TCV. Despite the decrease in BP, TCV normalized RBF in SHR, perhaps due to the blockade of renal angiotensin II.

Left ventricular function of the heart regressed by nifedipine in spontaneously hypertensive rats

Left ventricular (LV) performance of the pharmacologically regressed heart in hypertension is still unclear. We compared LV function of the heart regressed by nifedipine with that of the hypertrophied heart in spontaneously hypertensive rats (SHR). Nifedipine (30 mg/kg/day in food) was given to 15-week-old male SHR for 20 weeks (n = 12). Age- and sex-matched SHR served as controls (n = 12). LV catheterization was performed using a micromanometer and cardiac output was determined by the thermodilution method. Hemodynamic studies were performed after washout of nifedipine (24 h), when blood pressure had returned to the untreated level. Peak pumping ability was assessed during acute volume loading with saline. Nifedipine significantly decreased blood pressure in conscious animals (222 +/- 11 to 201 +/- 12 mmHg, p < 0.01) and reduced LV weight (1.20 +/- 0.07 to 1.07 +/- 0.05g, p < 0.01). After washout of nifedipine, LV systolic and end-diastolic pressures, dp/dtmax and cardiac output determined under pentobarbital anesthesia were similar in the treated and untreated groups. Peak pumping ability during acute preload elevation was also similar in the 2 groups. Plasma norepinephrine was unaltered, and plasma renin activity was significantly lower in the treated rats (p < 0.05). These results indicate that nifedipine regressed LVH with a minimal reduction of blood pressure and without evidence of neurohumoral activation or volume retention. In conclusion, LV function of the heart regressed by nifedipine was preserved after a spontaneous rise in blood pressure and during acute preload elevation.

Converting enzyme inhibition improves congestion and survival in hypertensive rats with high-output heart failure

The effects of angiotensin-converting enzyme (ACE) inhibitors in high-output heart failure have not yet been well established. We evaluated the effects of lisinopril (3 mg/kg/day) on hemodynamics, neurohormones, and survival in 10-week-old spontaneously hypertensive rats (SHR) with aortocaval fistula. Sham-operated treated and untreated SHR served as controls. Cardiac output (CO) was determined by thermodilution method, and renal blood flow (RBF) was assessed by laser-Doppler flowmetry. In sham-operated SHR, 2-week treatment with lisinopril decreased blood pressure (BP), left ventricular (LV) weight, and total peripheral resistance (TPR) (p < 0.01 each) and increased RBF and plasma renin activity (PRA) (both p < 0.05); CO and LV end-diastolic pressure (LVEDP) were unchanged. Fistula creation induced biventricular hypertrophy and high-output heart failure [increased LVEDP, CO, pulse pressure, and plasma norepinephrine (NE) and decreased RBF] with congestive signs (ascites, tachypnea). Lisinopril decreased LVEDP (p < 0.01), increased RBF, prolonged survival (both p < 0.05), and prevented ascites (0 vs. 46%) and increased PRA (p < 0.05) and attenuated the increase in plasma NE. Heart weight, BP, and CO were not affected by lisinopril. Thus, lisinopril ameliorated congestion and improved survival in SHR with fistula without compromising cardiorenal hemodynamics. Venous and renal dilatation and attenuation of vasoconstrictive systems may have contributed to the beneficial effects.

Effects of renal denervation on pressure-natriuresis in spontaneously hypertensive rats

To investigate the role of renal sympathetic nerve activity (RSNA) under developing and established hypertension, renal function was studied in chronically renal-denervated and sham-operated male spontaneously hypertensive rats (SHR) and control Wistar Kyoto rats (WKY) at 8 (early hypertensive) and 22 (established hypertensive) weeks of age. To further characterize the renal pressure-natriuresis-diuresis relationship in SHR, renal perfusion pressure (RPP) was reduced by aortic constriction to the level seen in age-matched WKY and the same studies were repeated. After denervation, urinary sodium excretion (UNaV), fractional excretion of sodium (FENa) and urine flow (UF) were increased in 8-week-old SHR (p < 0.01). With the exceptions of UNaV and FENa in denervated 8-week-old SHR, renal cortical blood flow, glomerular filtration rate, UF, UNaV and FENa decreased with the reduction of RPP in all of the SHR groups. These results suggest that RSNA significantly influences renal sodium and fluid handling, thus contributing to the shifting of the arterial pressure-renal sodium excretion curve to the right along the pressure axis and/or to an increase in the steepness of the relationship in 8-week-old SHR. There appeared to be a marked difference in renal sodium handling between 8- and 22-week-old SHR.

Long-term alpha 1 blockade does not reverse cardiac hypertrophy in spontaneously hypertensive rats

Not all antihypertensive drugs induce regression of left ventricular (LV) hypertrophy in hypertension, although they may equally lower blood pressure. The effects of alpha 1-blockers on regression have been inconsistent. In this study, bunazosin, a selective alpha 1-blocker, (15 mg/kg/day in food) was given to male spontaneously hypertensive rats (SHR) from 15 to 35 weeks of age to evaluate its effects on cardiac hypertrophy, hemodynamics, and neurohumoral factors. Age- and sex-matched SHR served as controls. LV function and cardiac output were determined by a micromanometer and thermodilution, respectively. Bunazosin significantly decreased blood pressure in conscious rats (from 209 to 192 mmHg, p < 0.01) but did not reduce LV mass. Heart rate, LV end-diastolic pressure, dp/dtmax, and cardiac output were similar in the 2 groups. Plasma renin activity was unaltered but plasma norepinephrine levels were higher in the treated rats (p < 0.05). Thus, bunazosin produced a significant relative reduction of blood pressure but did not reverse LV hypertrophy in SHR. Inadequate afterload reduction (8%) due to severe hypertension (> 200 mmHg) may explain the absence of regression. The rise of plasma norepinephrine levels may also offset the beneficial effects of bunazosin.

Haemodynamic and neurohumoral changes in spontaneously hypertensive rats with aortocaval fistulae

1. Our aim was to evaluate the effects of an aortocaval fistula (1 mm) on cardiorenal haemodynamics, cardiac hypertrophy and neurohumoral factors in spontaneously hypertensive rats and to compare the results with those observed in Wistar rats at 2 weeks after fistulae placement. Sham-operated spontaneously hypertensive rats and Wistar rats served as controls. 2. Heart weight was significantly increased in spontaneously hypertensive rats (34%) and in Wistar rats (43%) at 2 weeks after fistula creation. Left ventricular systolic pressure and dp/dtmax. were significantly decreased (both P < 0.01) in spontaneously hypertensive rats with fistulae which had higher left ventricular end-diastolic pressure than Wistar rats with fistulae (P < 0.01). Signs of circulatory congestion (ascites, tachypnoea, prostration) were observed only in the overloaded spontaneously hypertensive rats (45%). Cardiac index was comparably increased in both fistulae groups due to an increase in stroke index, since heart rate was not increased. 3. Fistulae placement decreased renal blood flow and kidney weight, and increased blood urea nitrogen to a greater degree in spontaneously hypertensive rats (all P < 0.05); serum creatinine levels were unaltered. Plasma noradrenaline concentration was increased in spontaneously hypertensive rats with fistulae (P < 0.05), whereas plasma renin activity was not changed. 4. Thus, spontaneously hypertensive rats with fistulae developed overt haemodynamic signs of high-output heart failure with frequent ascites and dyspnoea, whereas most of these findings were milder or absent in Wistar rats. This model provides an opportunity to evaluate the pathophysiological and pharmacological responses in high-output heart failure.

Hemodynamic and neurohumoral responses to exercise in patients with congestive heart failure

Hemodynamic and neurohumoral responses to supine bicycle exercise were evaluated in 16 patients with congestive heart failure (New York Heart Association functional class II-III) and in 8 normal controls. We determined cardiac output by the dye-dilution method, and forearm hemodynamics by plethysmography. The patients had lower resting cardiac and stroke indexes (p < 0.05) than the normal controls. During exercise, the increase in the cardiac index due to an increase in heart rate, was less than that in the controls. Resting and exercise systemic vascular resistance indices were higher in the patients (p < 0.05). The patients had lower resting forearm blood flow and higher forearm vascular resistance (p < 0.05), and the increases during exercise were comparable in the 2 groups. However, forearm venous tone and venous pressure increased more in the patients (p < 0.05). Exercise duration was shorter in the patients (p < 0.01). Resting plasma angiotensin II and norepinephrine were similar in the 2 groups, but plasma 6-keto-prostaglandin F1 alpha and atrial natriuretic peptide were higher in the patients. During exercise, all of these neurohumoral parameters rose more in the patients than in the controls (p < 0.05). Thus, the patients exhibited impaired central and peripheral hemodynamics both at rest and during exercise. The excessive exercise responses of all of the neurohumoral factors suggest that both vasoconstrictor and vasodilator systems are activated in heart failure.

Lisinopril reduces cardiac hypertrophy and mortality in rats with aortocaval fistula

We evaluated the effects of lisinopril (1 mg/kg per day) on hemodynamics, cardiac hypertrophy, and neurohumoral factors in Wistar rats with an abdominal aortocaval fistula. After 4 weeks of treatment, the results were compared with values obtained for untreated rats with a fistula and for sham-operated rats. Volume loading induced biventricular hypertrophy, hemodynamic signs of high-output heart failure (increased cardiac output, left ventricular end-diastolic pressure, and pulse pressure), and impaired renal function (decreased renal blood flow and kidney weight; increased blood urea nitrogen). Lisinopril did not affect these cardiorenal hemodynamics, but decreased left ventricular mass and mortality rate (both P < 0.05). Lisinopril attenuated the increase in plasma norepinephrine, and increased plasma renin activity (both P < 0.05). Thus, lisinopril reduced left ventricular mass and mortality in rats with high-output heart failure without changing the cardiorenal hemodynamics. Neurohumoral inhibition may play a role in the beneficial effects of lisinopril.

Marked increase in plasma interleukin-6 in burn patients

We measured the levels of interleukin-6 in plasma samples from 18 consecutive burn patients, including three lethal cases, during the early postburn period. In survivors burn injury caused initial increases in interleukin-6 levels that peaked at 6 hours after burn; this was significantly higher than interleukin-6 levels in normal controls (718 +/- 216 vs 70 +/- 4 pg/ml; p < 0.01). The increment in nonsurvivors was even more prominent (11,554 +/- 4,407 pg/ml; p < 0.01). The peak interleukin-6 levels at 6 hours correlated with total burn surface area (r = 0.65, p < 0.025), and tended to be higher in patients with inhalation injury. These data provide evidence that burn injury causes rapid release of interleukin-6 according to the severity of the injury. We also measured acute-phase reactants including fibrinogen, alpha 1-antitrypsin, C1 inhibitor, and alpha 2-plasmin inhibitor. After initial declines, these four proteins increased rapidly in survivors. In addition, the peak interleukin-6 levels correlated well with the increases in fibrinogen (p < 0.025), alpha 1-antitrypsin (p < 0.01), C1 inhibitor (p < 0.01), and alpha 2-plasmin inhibitor (p < 0.0001). In contrast, despite the marked increase in interleukin-6, the levels of acute phase proteins in nonsurvivors remained low. Based on these observations, we suggest that interleukin-6 is released as an alarm signal and has a role for the wound healing in burn patients, and that the levels of interleukin-6 after injury is an indicator of the severity of burn.

Effects of lisinopril upon cardiac hypertrophy, central and peripheral hemodynamics and neurohumoral factors in spontaneously hypertensive rats

OBJECTIVE

Left ventricular function (LVF) after reversal of left ventricular hypertrophy (LVH) with antihypertensive therapy is still controversial. The present study was undertaken in spontaneously hypertensive rats (SHR) to determine whether LVF of the regressed heart with lisinopril is normally maintained.

DESIGN

We compared cardiac function of SHR after reversal of LVH induced by lisinopril with that observed in control SHR and also with effects after a 4-week washout period.

METHODS

Administration of lisinopril began at 15 weeks of age and continued for 20 weeks. Cardiac index, renal blood flow, leg muscle blood flow, plasma renin activity, atrial natriuretic peptide level, and norepinephrine concentration were determined.

RESULTS

Lisinopril decreased body weight, blood pressure and left ventricular weight and increased leg muscle blood flow; cardiac index and renal blood flow were unaltered. Although norepinephrine concentration was unchanged, plasma renin activity increased and atrial natriuretic peptide decreased in treated SHR. Peak left ventricular pumping ability during volume loading was comparable in the two groups. After a 4-week washout period, left ventricular mass and blood pressure increased but remained lower than controls; cardiac index at rest and during volume loading was similar in the two groups.

CONCLUSIONS

These data indicate that LVF of the regressed heart induced by lisinopril was well preserved at rest, during volume loading and also after spontaneous recurrence of hypertension in SHR.

Nifedipine in divided doses does not reverse left ventricular hypertrophy in spontaneously hypertensive rats

This study investigated whether nifedipine administered in divided daily doses would diminish left ventricular hypertrophy (LVH) in spontaneously hypertensive rats (SHR). We administered nifedipine (12 mg/kg/day) in 3 divided doses by gastric gavage to 15-week-old male SHR (n = 10) for 4 weeks. Age- and sex-matched SHR served as controls (n = 10). Left ventricular (LV) function was evaluated by LV catheterization and cardiac output was determined by the thermodilution method. Plasma renin activity (PRA) and plasma norepinephrine levels were measured. Nifedipine significantly decreased blood pressure (p less than 0.01), shortened time constant T (p less than 0.05), and increased cardiac output (p less than 0.05). Nifedipine did not impair the LV systolic and diastolic indices during acute afterload elevation with angiotensin II. LV weight was similar in the 2 groups of rats. While PRA was unaltered, plasma norepinephrine levels were higher in the nifedipine-treated rats (p less than 0.05). These data indicate that nifedipine in 3 divided doses reduced blood pressure in SHR without compromising cardiac function but did not reverse LVH. The short hypotensive duration of nifedipine and its enhancement of sympathetic nervous activity may be responsible for the failure to reverse LVH, despite adequate blood pressure control.

[Disseminated intravascular coagulation in the early stage after severe burn: the role of excessive thrombin generation]

The pathogenesis of disseminated intravascular coagulation (DIC) in the early stage after burn injury remains still unclear. We investigated 12 burn injured patients by serial determination of anti-thrombin III (AT-III) activities and thrombin-antithrombin III complex (TAT) levels. Of these patients 4 developed DIC (DIC group) and the others had no hematological complications (non-DIC group). The mean levels of TAT increased markedly and peaked at 6 hr; the increment being more pronounced in DIC group (p less than 0.001). A significant correlation was recognized between TAT and Burn Index (r = 0.871, p less than 0.001). We also observed low AT-III activities those inversely related to Burn Index (r = 0.875, p less than 0.001), whereas closely correlated with serum albumin levels (r = 0.864, p less than 0.001), suggesting that this depression might be caused by both massive infusion and shifts of plasma into the extravascular space rather than consumption. These findings suggest that massive thrombin generation and decrease of anticoagulant activity, correlated to the severity of burns, might concurrently develop. Non-DIC group may remain to latent activation of coagulation cascade where anticoagulants could inactivate thrombin generated. This compensatory mechanism may fail in severe burn patients who have Burn Index of more than 90, developing DIC with high levels of TAT (316.3 +/- 104.5 ng/ml) and low AT-III activities (19.5 +/- 8.7%).

[Driver identification of the motorcycle in motorcycle/car accidents]

A series of motorcycle/car collision experiments and in-depth investigations involving motorcycle/car accidents with two riders were carried out in order to study the difference in behavior and injuries between the driver and the passenger of the motorcycle during a collision, and to provide general data for identifying their seat positions on the motorcycle in traffic accidents. In all the tests, two Hybrid II dummies were seated on the double seats of the motorcycle as riders. The motorcycle collided against the front door, front end or rear door of the passenger car at a speed of 50 km/h, at impact angles of 60 degrees, 90 degrees or 120 degrees. The speeds of the passenger car were tested at 0 km/h or 25 km/h. With different speeds of vehicles and different impact angles, the difference in rider behavior between the driver and the passenger was distinctly verified by analysis of high speed films. It is possible to distinguish the driver's injuries from the passenger's. The abrasion and/or contusions in the chest, face and groin area were severe for the drivers, but less serious for the passengers. The typical injuries of the driver can be expected in terms of the rider behavior during collision from 25 ms to about 150 ms after starting contact. The data and information can be used to clarify the question of who was driving in accident reconstruction.

[A case of severe tetanus associated with sympathetic overactivity]

A case of severe tetanus showing clinical features compatible with sympathetic overactivity (SOA) is reported. A 64-year-old man was admitted to our hospital 6 days after injury. The clinical signs of SOA developed on the second day in ICU. Through the clinical investigation of this case, we found out and insisted on some new concepts about the clinical features of SOA. 1. Lability of arterial pressure is parallel to that of catecholamine level in serum. 2. Two different types in SOA were found. One is dominantly lable type of Adrenaline and another is of Noradrenaline. 3. Drawing a sharp line between 2 types by assessment of circulatory data from Swan-Ganz catheter is significant for deciding therapeutic lines.

[Effect of active oxygen on cytoplasmic Ca2+ sequestration mechanism]

Effects of the active oxygen on the extrusion mechanism of once-increased cytoplasmic Ca2+, which causes various physiological phenomena, were investigated using different kinds of culture cells. First we found that, in response to stimulation with vitamin K (VK), various culture cells showed a decrease in cytoplasmic Ca2+ concentration. On the presumption that this phenomenon might be related to the oxidizing action of VK, we performed the same experiments using oxidizing agents such as H2O2 or KO2. They also showed a decrease in cytoplasmic Ca2+ concentration. Furthermore, they suppressed the increase of cytoplasmic Ca2+ by vasopressin. It would be inferred from these results that the active oxygen may act upon some site of the cellular signal transduction system of cell membrane to lower the cytoplasmic Ca2+ level.

Cardiorenal effects of an orally active dopamine prodrug (TA-870) in patients with congestive heart failure

The effects of TA-870, a newly synthesized orally active dopamine prodrug, on the cardiorenal functions were investigated in 12 patients with severe chronic congestive heart failure. A single oral dose of TA-870 (1,200 mg) improved left ventricular fractional shortening and mean circumferential velocity on M-mode echocardiography (p less than 0.01 for both). Renal plasma flow and glomerular filtration rate improved with TA-870 (p less than 0.01 and p less than 0.05, respectively); urine volume and sodium excretion increased (p less than 0.01 for both). Blood pressure and heart rate did not change during the 4-h experimental period. Mean plasma free dopamine levels peaked 1 h after dosing. These data suggest that the cardiorenal effects of oral TA-870 are comparable with those of continuous intravenous injections of dopamine. Thus, TA-870 appears to be a useful alternative drug to intravenous dopamine.

[A clinical study of pulmonary edema on paraquat poisoning by double indicator dilution method using heat and sodium]

We studied the formation of pulmonary edema on 9 patients with paraquat poisoning using thermal-sodium double indicator dilution method for the measurement of lung water. In survivors group (n = 4) extravascular thermal volume (EVTV) was not almost changes. In non-survivors group (n = 5) EVTV increased about three times as much as that in survivors group on 32 hours after admission. EVTV was correlated with PCP-PCOP in both survivors group and non-survivors group (n = 64, r = 0.665, p less than 0.01). But EVTV in non-survivors group was higher than that in survivors group within same PCP-PCOP. In non-survivors group delta EVTV/delta (PCP-PCOP) in 24 hours after admission was correlated with initial PCP-PCOP (r = 0.984, p less than 0.01). We propose that the formation of pulmonary edema on paraquat poisoning is mainly due to the increased capillary permeability, influenced by the increased pressure gradient of capillary barrier.

[Biomechanical analysis of the pulmonary trauma by localized blunt force--thoracic force-deflection in pigs]

Thoracic force-deflection characteristics have been measured in the living little pigs as a step towards the analysis of thoracic injury in the field of forensic medicine. Mechanisms of injury by hand impact with a small stone were investigated by means of high speed video/camera and load cell. Initial velocity by hand impact ranges from 5.8 to 11.1 m/s, with corresponding peak force from 24 to 122 kgf. The thoracic force-deflection of the pig shows a progress change with increasing impact velocity, showing more of a spring-mass like response with an initial linear region of stiffness during a short interval immediately after the impact. Peak force up to 122 kgf was developed for 77 mm in the localized thoracic displacement with rib fractures and serious lung injury. A few rib fractures occurred with initial velocity near 9 m/s and displacement near 50 mm, these data suggest an outbreak limit of rib fractures of the little pig.

Peripheral hemodynamic effects of captopril in patients with congestive heart failure

In 14 patients with severe congestive heart failure, the effects of captopril on the forearm circulation were evaluated with strain gauge plethysmography. Changes in plasma renin activity, angiotensin II, norepinephrine, epinephrine, bradykinin, prostaglandin E2, and 6-keto-prostaglandin F1 alpha concentrations were also measured. To determine whether the prostaglandins contribute to the peripheral hemodynamic response to captopril, the hemodynamic and hormonal measurements were repeated after pretreatment with indomethacin, an inhibitor of prostaglandin synthesis. Ninety minutes after administering a single dose of captopril (25 mg), mean blood pressure and venous pressure decreased (p less than 0.01 and p less than 0.05, respectively), forearm blood flow and maximum venous volume increased (p less than 0.05 for both), and forearm vascular resistance and forearm venous tone decreased (p less than 0.05 for both). Captopril also improved forearm venous distensibility (p less than 0.05). Pretreatment with oral indomethacin (50 mg) significantly blunted all of these captopril-induced hemodynamic changes. The blockage of the renin-angiotensin system by captopril was unaltered by indomethacin pretreatment. Captopril significantly increased plasma bradykinin, prostaglandin E2, and 6-keto-prostaglandin F1 alpha (p less than 0.05 for each). Indomethacin pretreatment did not affect the captopril-induced increase in bradykinin, but it did completely eliminate the increase in the prostaglandins. Plasma catecholamines did not change with captopril. These data suggest that the vasodilator prostaglandins play a significant role in captopril's peripheral vasodilative effects in congestive heart failure.

Histochemical demonstration of phenobarbital by immunocytochemistry

A method for the demonstration of the topographical distribution of phenobarbital at the cellular level in various tissues was established. Mice that had been exposed to various doses of phenobarbital by intraperitoneal injection were killed, and their tissues were fixed with 0.1 M phosphate buffer solution (pH 7.4) containing paraformaldehyde and glutaraldehyde. Thereafter, paraffin and frozen sections were made and stained by the indirect immunoperoxidase method using antisera obtained from commercial sources and used for the immunochemical assay of the blood level of phenobarbital in clinical medicine. A specific positive reaction was observed solely in testing the intoxicated tissues, and this reaction was inhibited when phenobarbital was added to the antisera. The minimal sensitivity of the positive reaction, which can be discerned by observing the stained slides macroscopically, was in the range of 10 mg/kg. Thus, the diagnosis of phenobarbital intoxication in the forensic autopsy can be made by immunohistochemistry. A positive reaction was found in various tissue cells, including nerve cells, myelin sheaths, glia cells, hepatocytes, cells of the alveolar and bronchial wall, epithelial cells of the distal part of the renal tubules, and so forth. Endothelial cells of the capillaries in all tissues gave a strong positive reaction. The immunocytochemical electron microscopy of the hepatocytes revealed that the positive reaction in the cytoplasm was located solely in the intraluminal space of the smooth endoplasmic reticulum. These results indicate some interesting aspects of the pharmacokinetics of phenobarbital in vivo. It is expected that the antisera, which are used widely for the assay of the blood concentration of various drugs (phenobarbital, amphetamines, morphine, and so forth), may be regarded as excellent reagents for immunocytochemistry. This clearly indicates that morphological evidence in toxicology, which had so far remained obscure, can be easily obtained by applying these antisera against various drugs.

Effects of captopril on peripheral hemodynamics in severe congestive heart failure

The effects of captopril on the forearm hemodynamics in patients with severe congestive heart failure were studied, using strain-gauge plethysmography. To determine whether prostaglandins are involved in the captopril actions, indomethacin, an inhibitor of prostaglandin synthesis, was administered. In 8 patients, captopril (25 mg) decreased mean blood pressure (P less than 0.01) and venous pressure (P less than 0.05); forearm blood flow (P less than 0.05) and maximum venous volume (P less than 0.05) were increased; forearm vascular resistance (P less than 0.05) and forearm venous tone (P less than 0.05) were decreased. Venous distensibility was improved with captopril (P less than 0.05). All the hemodynamic changes were attenuated by indomethacin (50 mg). Captopril increased circulating bradykinin (P less than 0.05), prostaglandin E2 (P less than 0.05) and 6-keto-prostaglandin F1 alpha (P less than 0.05). Indomethacin did not affect bradykinin level but blocked the increase in prostaglandins. These data suggest that captopril dilates both arterial and venous vessels not only by blocking the renin-angiotensin system but by increasing local or circulating vasodilator prostaglandins.