Fractional myocardial flow reserve (FFRmyo) after coronary intervention as a predictor of chronic restenosis

The angiographic assessment of coronary stenosis has many limitations, especially after coronary intervention. To determine the physiologic significance of such lesions, we measured the mean translesional pressure gradients at rest (P1), those during hyperemia induced by intracoronary administration of papaverine (12 mg in the left and 8 mg in the right coronary artery) (P2), and fractional myocardial flow reserve (FFRmyo) which is derived from the ratio of the mean distal coronary pressure and aortic pressure during hyperemia. Our objective was to determine the relations among P1, P2, and FFRmyo and restenosis as potential predictors of chronic restenosis. The grouped study consisted of 32 patients with ischemic heart disease scheduled to undergo intervention. The distal coronary pressure was measured using a 0.014 inch pressure monitoring wire (Pressure Guide, Radi Medical Systems, Uppsala, Sweden). The guidewire was advanced through the lesional segment. The mean percent diameter stenosis (%DS) was 67.9 +/- 13.3% before intervention and 22.9 +/- 15.3% after intervention. The mean P2 (9.9 +/- 5.3 mmHg) was significantly higher than the mean P1 (4.5 +/- 3.6 mmHg; p < 0.0001). There was no correlation of P1, P2 or FFRmyo with the %DS after intervention. Follow-up angiography (after 6 months) performed on all patients revealed restenosis (%DS > or =50%) in four patients (12.5%). There was no correlation between P1 and the %DS at the follow-up angiography, but the relation between P2, FFRmyo and the %DS at the follow-up angiography was significant (r = 0.599, p < 0.01; r = 0.703, p < 0.0001, respectively). As a measurement of P2, FFRmyo is useful for the determination of the endpoint of intervention in consideration of prevention of restenosis. A new endpoint may be established after further evaluation in a greater number of patients.

[Investigation of pulmonary hemodynamics and chest X-ray findings in hypercapnic patients with pulmonary tuberculosis sequelae]

We investigated pulmonary hemodynamics and chest X-ray findings to explore pathophysiological significance of chronic hypercapnia in patients with pulmonary tuberculosis sequelae. One hundred and seven patients underwent examinations of blood gases and right cardiac catheterization. The patients were divided into two groups, according to arterial carbon dioxide tension under room air breathing (PaCO2). Group I (n = 35) was defined as 45 Torr or lower of PaCO2, and Group II (n = 72) was the hypercapnic group whose PaCO2 was over 45 Torr. In addition, spirometry was done in 34 patients of Group I and 68 of Group II. First, the values of blood gases, spirometry and pulmonary hemodynamics were compared between the two groups. Secondly, between 22 of Group I and 50 of Group II, the values of pulmonary arteriolar resistance (PAR) before and after 100% oxygen breathing for 10 minutes were compared. These comparisons were made by exploratory data analysis. Lastly, we described in all cases with five items of chest X-ray findings and the extent of each finding we had defined. The items were emphysematous change; fibrosis, bronchiectasis, and/or cavity (hereafter abbreviated as "fibrosis"); lung resection and/or atelectasis; pleural thickening; and thoracoplasty. We explored the items of X-ray findings which may relate to hypercapnia by ridit (abbreviation for "relative to an identified distribution") analysis. The results were as follows. (1) Hypercapnic patients tended to have severer restrictive ventilatory impairment and hypoxemia. Under an even level of arterial oxygen tension (PaO2), tissue oxygenation was not poorer in Group II than in Group I. (2) Hypercapnic patients tended to have more unfavorable pulmonary hemodynamics. More than half of them had pulmonary hypertension defined as 20 mmHg or higher of pulmonary artery mean pressure (PAm). Under an even level of PaO2, PAm was higher in Group II. Although 34 patients of Group II showed PaO2 over 60 Torr, 23 of them had pulmonary hypertension. (3) PAR after oxygen breathing was more likely to decrease in Group II than in Group I. (4) As any mean ridit was standardized and adjusted to 0.5 in Group I, the maximum was the mean ridit of "pleural thickening" (= 0.67), next "fibrosis" (= 0.65) in Group II. The above two items of X-ray findings, in which each mean ridit was higher than in any other item, were more influential on hypercapnia. We conclude as follows. (1) Pulmonary hypertension is severer in hypercapnic patients with pulmonary tuberculosis sequelae; it may be mainly attributable to hypoxic pulmonary vasoconstriction. (2) An important cause of chronic hypercapnia may be pathological changes such as "pleural thickening" and "fibrosis" seen on the radiogram.

Manifestation of pulmonary hypertension during REM sleep in obstructive sleep apnea syndrome

The effect of sleep stage change on pulmonary circulation has not been well documented in patients with obstructive sleep apnea syndrome (OSAS). We investigated whether or not stage-specific change can affect pulmonary artery pressure (Ppa) in patients with OSAS. Thirty-one patients with OSAS underwent right cardiac catheterization in the daytime and the following night, including 19 patients in whom Ppa could be measured throughout non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. Ten of the 19 patients had daytime pulmonary hypertension (PH) defined by a mean Ppa (Ppa) >/= 20 mm Hg. Then we analyzed Ppa response to hypoxia spontaneously occurring during the period of sleep apnea. The slopes of the regression lines between arterial oxygen saturation measured by pulse oximeter (SpO2) and Ppa curves were almost the same in both NREM and REM patient groups with or without daytime PH, whereas the response curve was significantly shifted upward in REM compared with NREM patients with daytime PH. Furthermore, Ppa was elevated more markedly in association with REM burst, phasic REM, compared with tonic REM. We conclude that vascular tone of pulmonary artery could be elevated in association with REM sleep which is independent of the degree of hypoxia, and that this state-specific change is manifested in patients with daytime PH.

[Pulmonary hemodynamic and gas exchange effects of various oxygen concentrations in patients with severe pulmonary hypertension primarily affecting the pulmonary vasculature]

The aim of this study was to evaluate pulmonary hemodynamic and gas exchange response to oxygen inhalation in patients with severe pulmonary hypertension primarily affecting the pulmonary vasculature. This study included 7 patients with primary pulmonary hypertension (PPH), 11 with pulmonary hypertension related to collagen vascular diseases (CoPH), and 18 with chronic thromboembolic pulmonary hypertension (CTEPH). All patients had mean pulmonary arterial pressure (PPAm) of greater than 25 mm Hg. We divided the patients into two groups: a PPH + CoPH group comprising the 7 PPH and 11 CoPH patients, and the CTEPH group. We measured cardiopulmonary variables after 10 min inhalation of various oxygen concentrations (FiO2 0.24, 0.28, 0.4, 1.0). In the PPH + CoPH group, PPAm significantly decreased after the inhalation of oxygen concentrations of 40% or more. This was associated with a significant reduction in pulmonary arteriolar resistance (PAR), and suggested active pulmonary vasodilation was caused by oxygen inhalation. In the CTEPH group, on the other hand, PPAm significantly decreased after the inhalation of oxygen concentrations of 28% or more, apparently in association with a significant fall of cardiac output. However, PAR was unchanged regardless of the inspired oxygen concentration, indicating an absence of pulmonary vasodilation in the CTEPH group. When breathing room air, 7 patients in the PPH + CoPH group (38.9%) and 10 in the CTEPH group (55.6%) demonstrated mixed venous oxygen tension (PvO2) values of less than 35 Torr. Extra attention should be paid to PvO2 when administering oxygen therapy to patients with severe pulmonary hypertension.

Association between smoking and tumor progression in Japanese women with adenocarcinoma of the lung

We studied the effect of smoking on tumor progression in 3312 patients with lung cancer registered at the National Matsudo Hospital and National Cancer Center Hospital East between 1977 and 1996. The odds ratios of the following variables for tumor extent (localized versus advanced disease) and hazard ratios for survival were calculated in both sexes separately using the logistic regression and Cox proportional hazard models, respectively: smoking history, number of cigarettes smoked per day, pack-years smoked, age, histological type, and the year of admission. Of the 943 women, 367 (38.9%) were smokers and 694 (73.6%) had adenocarcinoma, whereas of the 2369 men, 2255 (95.2%) were smokers and 1010 (42.6%) had adenocarcinoma. In female adenocarcinoma patients, the odds ratio (95% confidence interval) for advanced disease and the hazard ratio (95% confidence interval) for survival with an increase of 30 cigarettes smoked per day were 2.86 (1.49-5.49) and 1.52 (1.13-2.04), respectively, but in those with non-adenocarcinoma, the odds ratio and hazard ratio were 0.96 (0.41-2.23) and 1.13 (0.75-1.70), respectively. In male patients, smoking history influenced tumor progression regardless of histological type, but the odds ratios and hazard ratios were lower than those for women with adenocarcinoma. In conclusion, smoking habit was closely correlated with progression of adenocarcinoma in women. This association was not observed in women with non-adenocarcinoma and was weaker in men, suggesting various effects of smoking on lung cancer development depending on gender and the histological type of the tumor.

[Investigation of pulmonary hemodynamics and chest X-ray findings in patients with pulmonary tuberculosis sequelae and obstructive ventilatory impairment]

We investigated pulmonary hemodynamics and chest X-ray findings to explore significance of obstructive ventilatory impairment in patients with pulmonary tuberculosis sequelae. One hundred and two patients underwent examinations of blood gases, spirometry, and right cardiac catheterization. The patients were divided into two groups, according to forced expiratory volume in one second as the percentage of forced vital capacity (FVC), which was expressed as FEV1%. Group A (n = 38) had FEV1% of 55% or lower and Group B (n = 64), FEV1% above 55%. First, the values of blood gases and hemodynamics were compared between the two groups, regarding the percent predicted value of FVC as a covariate. Secondly, between 26 of Group A and 42 of Group B, the change of pulmonary arteriolar resistance (PAR) before and after 100% oxygen breathing for 10 minutes was compared. These comparisons were made by exploratory data analysis. Lastly, we described every case with five items of chest X-ray findings and the extent of each finding we had defined. The items were emphysematous change; fibrosis, bronchiectasis and/or cavity; pulmonary resection and/or atelectasis; pleural thickening; and thoracoplasty. We explored X-ray findings influenced on airway obstruction by ridit (abbreviation for "relative to an identified distribution") analysis, taking smoking status into consideration. The results were as follows. (1) The patients of Group A tended to show severer hypoxemia and tissue hypoxia than the patients of Group B. (2) The patients of Group A tended to show worse values of pulmonary hemodynamics than the patients of Group B. Under an even level of the arterial oxygen tension that was 60 Torr or lower, pulmonary artery mean pressure was higher in Group A than in Group B. (3) PAR after oxygen breathing was less likely to decrease in Group A than in Group B. (4) As any mean ridit was standardized and adjusted to 0.5 in Group B, every mean ridit of "emphysematous change" in Group A was the largest-0.63 in non-smokers, 0.74 in ex-smokers and 0.70 in current smokers. Therefore, "emphysematous change" was more influenced on airway obstruction than any other finding because of the largest mean ridit. We conclude as follows. Pulmonary hypertension is more serious in patients suffering from severe airway obstruction with pulmonary tuberculosis sequelae, and it may be attributable to reduction in capacity of anatomical pulmonary vascular bed rather than hypoxic pulmonary vasoconstriction. Pathological changes such as "emphysematous change" on the radiograph might be considered as an important cause of obstructive ventilatory impairment.

Prediction of life expectancy in patients with primary pulmonary hypertension. A retrospective nationwide survey from 1980-1990

Primary pulmonary hypertension (PPH) is a progressive disease of unknown etiology usually followed by death within 5 years after diagnosis. Although heart-lung or lung transplantation is now offered to patients with advanced PPH, adequate criteria assessing an accurate prediction of life expectancy in PPH has been difficult to establish. The aims of this study were to identify the characteristic features associated with a poor prognosis in patients with PPH, and to attempt to establish an individual prognostic index that predicts with great accuracy survival or death of PPH after one year, thereby helping to define criteria for patient selection for transplantation. In 1991, a retrospective nation-wide survey on PPH was conducted in Japan, and the clinical and cardiorespiratory variables of 223 PPH cases (female; 144, male; 79) in the period from 1980-1990 were obtained. The mean pulmonary arterial pressure (PPA) was 57.5+/-17.2 mm Hg (mean+/-SD), and the overall median survival time was 32.5 months since the first diagnostic catheterization. The characteristic features of 61 patients who died within one year of catheterization (Nonsurvivors group) were compared to 141 patients who survived one year or more from the time of catheterization (Survivors group). Among several clinical and cardiorespiratory variables, heart rate, PPA, right atrial pressure (PRA), stroke volume index (SI), pulmonary vascular resistance, and partial pressure of carbon dioxide (PaCO2) were significantly different between the two groups. As the independent factors, PPA, PRA, SI, and PaCO2 were selected for the multiple logistic analysis. Using a 0.7 probability cut-point to separate Nonsurvivors from Survivors, 84.6% of Nonsurvivors and Survivors could be correctly predicted from this logistic regression equation. Predictive equations like the present preliminary one can be used in the future to better assess life expectancy in patients with PPH in whom transplantation will be considered.

Oxidative stress and haematological changes in immobilized rats

Immobilization stress induces formation of reactive oxygen species (ROS) and leads to the oxidative injury in various tissues. In this study, the effects of immobilization stress on peripheral blood cells distribution, plasma level of thiobarbituric acid reactive substances (TBARS), and activities of antioxidant enzymes in erythrocytes were investigated in male Fischer rats. A significant increase in plasma TBARS was observed during and after the stress. Dramatic increases of neutrophils and monocytes imply that ROS formation resulted from their activation. Furthermore, the antioxidant activities of catalase and superoxide dismutase (SOD) in erythrocytes were dramatically increased during and after the stress, while a large fall in erythrocyte number was observed. These findings suggest that the activation of immune cells can be a source of the immobilization-induced ROS production, and that antioxidant enzymes in erythrocytes play an important role in preventing the ROS-induced injuries.

[Estimated numbers of patients with intractable respiratory diseases]

To estimate the number of patients with intractable respiratory diseases, we conducted a two-stage nationwide epidemiological survey in 1997. The first survey was performed at randomly sampled hospitals to identify the number of patients treated. The second survey sought detailed clinico-epidemiological data on the patients reported in the first survey. The response rates were 54% for the first survey and 62% for the second. Based on the survey findings, we derived the following nationwide estimates: 450 patients (95% confidence interval: 360-530) with chronic thromboembolic pulmonary hypertension; 230 (200-260) with primary pulmonary hypertension; 180 (150-210) with obesity-associated hypoventilation syndrome; 40 (30-50) with primary alveolar hypoventilation syndrome; 160 (140-180) with histiocytosis X; and 190 (150-230) with juvenile pulmonary emphysema.

Cloning of the mouse gene for D-dopachrome tautomerase

D-Dopachrome tautomerase converts 2-carboxy-2,3-dihydroindole-5, 6-quinone (D-dopachrome) into 5,6-dihydroxyindole. The amino acid sequence of this protein is 27% identical with that of macrophage migration inhibitory factor, which is known as a cytokine, pituitary hormone, and glucocorticoid-induced immunomodulator. In this study, we isolated and sequenced a 3490 bp-long genomic DNA of mouse D-dopachrome tautomerase that consists of three exons and two introns. By two procedures, 5' rapid amplification of cDNA ends and cap site labeling, we determined the transcription initiation site, which is located 46 bp upstream of the translation initiation site. The possible polyadenylation sequence (AATAAA) is located 180 bp downstream of the termination codon. Computer-assisted analysis of the nucleotide sequence revealed a number of regulatory motifs, including multiple sites for Sp1, C/EBP, NF-Y, and USF. Although the precise pathophysiological functions of D-dopachrome tautomerase remain to be elucidated, the present results will contribute not only to elucidation of the mechanism of gene expression, but also to understanding of the molecular function of this protein.

Low-grade pulmonary mucosa-associated lymphoid tissue lymphoma with or without intraclonal variation

We examined the immunoglobulin heavy chain variable (Ig VH) region genes of 11 low-grade pulmonary mucosa-associated lymphoid tissue (MALT) lymphomas by a two-step polymerase chain reaction (PCR) and sequencing analysis. We observed frequent somatic mutations with the positive selective pressure of the rearranged Ig VH genes in all cases, indicative of postgerminal center cell origin. Eight cases demonstrated intraclonal variations (hypermutation with intraclonal variation type), but the other cases showed only one major clone without intraclonal heterogeneity (hypermutation without intraclonal variation type). The former might reflect the reentry of marginal zone B cells into a germinal center environment leading to further mutations. The latter might be no longer susceptible to hypermutation mechanisms and seemed to be stable. Four cases used Ig VH genes (hv3019b9, VH26, and VH4.21), which are frequently found in a variety of autoantibodies, such as cold agglutinins, rheumatoid factors, and anti-DNA antibodies.

[When do strokes occur?--analysis of diurnal variation and activity during the onset]

The diurnal variation and activity during the onset of stroke were examined in more than 700 consecutive patients. 304 cases with hypertensive intracerebral hemorrhage (HIH), 214 cases with subarachnoid hemorrhage (SAH) and 201 cases with obstructive cerebrovascular disease (OCVD) were investigated about the time of onset. Concerning the activity during the onset, 296 cases with HIH, 215 cases with SAH and 198 cases with OCVD were examined. HIH occurred frequently between 1500-1800 hours, 0600-0900 hours and 1800-2100 hours. SAH occurred frequently between 0900-1200 hours, 1500-1800 hours and 1800-2100 hours. Both HIH and SAH were least likely to occur between 0000-0300 hours. OCVD exhibited a small peak incidence between 0900-1200 hours, but there were no differences between the groups for the other time periods. Both HIH and SAH were likely to occur frequently in the lavatory, while bathing and during meals. HIH also occurred frequently during physical work, while SAH occurred as frequently during mental work or housework as during hard physical labor. OCVD commonly occurred during sleep or relaxation. The relationship between diurnal variation in stroke and the circadian variation of blood pressure is discussed. The incidence of all three types of strokes during work was higher in the non-aged group (patients under 66 years) than in the aged group (patients over 66 years). HIH and SAH occurred associated with alcohol consumption more frequently in the non-aged group than in the aged group. It is likely that the difference of the time and of the activity during the onset between aged group and non-aged group reflects the difference of life-style between aged and non-aged people.

[Survival and pulmonary hemodynamics in patients with sequelae of pulmonary tuberculosis who received antituberculosis chemotherapy and home oxygen therapy]

To date, the pulmonary hemodynamics of patients with sequelae of pulmonary tuberculosis have usually been examined as a unified set of criteria regardless of the treatments that patients undergo. Attracted by this subject, we studied the cerrelations between survival and pulmonary hemodynamics in patients with sequelae of pulmonary tuberculosis who were treated with antituberculosis drugs and home oxygen therapy (HOT). Our study examined 21 patients with a mean ages of 58.0 years, mean PaO2 of 59.3 +/- 11.4 mm Hg, and mean PaCO2 of 51.9 +/- 6.3 mm Hg. In pulmonary function tests, mean % VC was 44.1 +/- 16.3%, and mean FEV 1%, 66.6 +/- 23.0%. Twenty of the patients were given a diagnosis of pulmonary hypertension. Eighteen of the patients received HOT; as a group, their 3-year survival rate was 62.6%, which was not statistically significant compared to survival observed in post Japanese studies. Among the HOT patients, blood gases and pulmonary hemodynamics did not vary significantly between those who died within 2 years after right heart catheterization (short-term survivors) and those who lived for more than 5 years (long-term survivors). However, VC, % VC, and FVC values were significantly lower in the short-term survivors than in the long-term survivors. In conclusion, these findings revealed no statistically significant, differences compared with the data from past studies. Although pulmonary hypertension is associated with the poor prognosis for chronic obstructive pulmonary tuberculosis patients, in the patients we studied, the principle prognostic determinant was the seriousness of the restrictive ventilatory impairment, not pulmonary hypertension.

Evidence for mRNA expression of vascular endothelial growth factor by X-ray irradiation in a lung squamous carcinoma cell line

Vascular endothelial growth factor (VEGF) is a multipotent cytokine which plays an important role in various angiogenic conditions as well as in some tumor behaviors. Here we examined the induction of VEGF mRNA by X-ray irradiation in a lung squamous cell carcinoma cell line (RERF-LC-AI). Irradiating the cells with 15 Gy X-rays significantly increased the mRNA expression up to 2.5-fold of control at a post-irradiation time of 16-24 h. The induction of VEGF mRNA by X-ray irradiation was completely blocked by treating cells with either genistein (Src tyrosine kinase inhibitor) or H7 (protein kinase C inhibitor). This suggests that the mechanism of induction might be concerned with the pathway which triggers Src tyrosine kinase of the cell surface and the protein kinase C pathway.

Rare pulmonary tumors - a review of 32 cases

In a review of pulmonary tumors diagnosed at our institute from 1976 to 1995, we found 20 malignant and 12 benign rare tumors, which accounted for 0.57 and 0.34% of all pulmonary tumors, respectively. The histological types of these rare malignant tumors were malignant lymphoma (6/20), carcinosarcoma (3/20), mucoepidermoid carcinoma (2/20), bronchial gland mixed tumor (2/20), adenocystic carcinoma (1/20), myoepithelioma (1/20), leiomyosarcoma (1/20), epitheloid hemangioendothelioma (1/20), hemangiopericytoma (1/20), malignant melanoma (1/20) and choriocarcinoma (1/20). Benign rare tumors involved papilloma (3/12), lipoma (3/12), leiomyoma (3/12), adenoma (1/12), fibroma (1/12), and meningioma (1/12). The clinical and pathological features of malignant tumors were roughly the same as those of common pulmonary carcinomas. In contrast, benign tumors were never larger than 3 cm and were more commonly located in the central parts of the lung, which explained the relatively frequent symptoms of wheezing and fever associated with obstructive pneumonia.

The Microwave Spectrum of n-Butyraldehyde Oxime

The microwave spectrum of n-butyraldehyde oxime was observed in the frequency region 26.5-40 GHz. Four rotational conformers were found to exist in the gas phase; among these, two conformers belonged to the (E)-geometrical isomer and the other two to the (Z)-geometrical isomer. The microwave spectrum attributed to one of these two rotational conformers of (E)-butyraldehyde oxime was analyzed, and its rotational constants for the ground vibrational state were determined: A = 15883(379), B = 1269.97(1), C = 1251.60(1) MHz. The conformational structure of the molecule is discussed, referring to the rotational constants obtained and the ab initio molecular orbital calculation. Copyright 1998 Academic Press.

[CABG after patch angioplasty of the left main coronary: artery report of a case]

A 57-year-old man was admitted to our hospital because of restenosis of the left main coronary trunk (LMT) after patch angioplasty for the LMT lesion. PTCA was repeated four times during three years after patch angioplasty, but recent coronary angiogram still demonstrated 75% restenosis of the LMT lesion. Double-CABG was performed to LAD and LCX using the left internal thoracic artery and saphenous vein graft. Postoperative coronary angiogram revealed an excellent result. A careful consideration must be given to the indication of the patch angioplasty of the LMT lesion.

What causes p53 mutations in patients with lung cancer?

We studied the association between occurrence of p53 mutations and both smoking history and family history of cancer (FH) in 109 lung cancer patients using the logistic regression model. A dose-response relationship between smoking defined as pack-years smoked (PY) and p53 mutations was clearly demonstrated [Odds ratio (OR) for PY 30-59: 1.92 (0.55-7.94); OR for PY 60: 4.21 (1.09-19.0); trend P=0. 04], but no association between p53 mutations and FH was obtained in male patients. In females, smoking habit [OR: 3.23 (0.48-25.4)] and FH [OR: 4.17 (0.84-25.0)] might both be associated with p53 mutations.

Role of p27Kip1 and cyclin-dependent kinase 2 in the proliferation of non-small cell lung cancer

The cell cycle is governed by a family of cyclin-dependent kinases (Cdks). Cdk2 forms a functional complex with cyclin E and plays a pivotal role in the regulation of G1/S transition. Cdk2 activity is negatively regulated by interactions with inhibitors. p27Kip1, one of the most potent inhibitors of Cdk2, was recently identified as a powerful negative prognostic marker in non-small cell lung cancer as well as in colorectal and breast cancer. In the present study, the expression of p27 and Ki-67 antigen in nonneoplastic and cancerous lung tissues was determined by immunohistochemistry. After establishing that the antibody-measured p27 labeling index was a good reflection of the level of p27 expression measured by Western blotting, we show that p27 labeling index is decreased in cancerous lung tissues, compared with nonneoplastic lung tissues, and exhibits a significant inverse relation to the proliferation marker Ki-67 antigen, detected with monoclonal antibody MIB-1. Consistent with these data, all cancerous lung tissues showed enhanced degradation activity of p27 compared with nonneoplastic lung tissues and, in addition, increased levels of the phosphorylated form of Cdk2, as determined with Western blot analysis. The H1 histone kinase activity associated with Cdk2 was also increased in non-small cell lung cancers. Statistical analysis showed that proliferative activity as measured by MIB-1 labeling index was highly correlated with Cdk2 activity (r = 0.767, P < 0.0015). These results suggest that p27 and Cdk2 may play an important role in the proliferation of non-small cell cancer.

Fas/FasL interaction is not involved in apoptosis of activated CD4+ T cells upon HIV-1 infection in vitro

In HIV-1-infected individuals, Fas expression and Fas/FasL-mediated apoptosis of mature T cells are known to increase compared with those in normal individuals. To elucidate a relation between acute HIV-1 infection and the regulation of Fas/FasL system upon T-cell activation, resting CD4+ T cells were acutely infected or uninfected with HIV-1 and subsequently activated by phorbol myristate acetate and ionomycin (PMA/IM). Four days after infection, when HIV-1 env gp120 is expressed in more than one half of activated T cells, Fas/FasL expression was analyzed by flow cytometry, and apoptosis-inducing activity of these activated primary CD4+ T cells on Fas+ Jurkat cells was examined. The level of Fas or FasL expression was not altered during acute HIV-1 infection. The enhanced apoptosis-inducing activity upon HIV-1 infection was observed in some individuals, but its activity was not Fas/FasL-mediated. These results indicate that HIV-1 infection is not necessarily associated with either upregulation of Fas/FasL expression or Fas/FasL-mediated apoptosis.

A new aspect of the carotid body function controlling hypoxic ventilatory decline in humans

Ventilatory response to eucapnic sustained mild hypoxia was measured in one patient with unilateral and three patients with bilateral carotid body (CB) resection (defined UR and BR, respectively). The profile of ventilatory response in UR patient was initially augmented then gradually declined (biphasic pattern) as generally seen in normal subjects although the absolute magnitude was substantially low. On the other hand, biphasic pattern was disappeared in all three BRs. Lack of hypoxic ventilatory decline (HVD) in the late period of sustained hypoxia was in marked contrast to that reported in the anaesthetized and CB-denervated animals whose ventilation was severely depressed lower than the pre-hypoxic control level. In view of recent knowledge that the analogous mild hypoxia in normal animals and humans elicits an useful adaptation to economize energy expenditure with maintaining reversible excitability in control of respiration, BR patients were considered to have lost this ability. We conclude that in awake humans the CB not only stimulates ventilation but also controls the degree of subsequent HVD during sustained hypoxia.

Fluorine-18-fluorodeoxyglucose and carbon-11-methionine evaluation of lymphadenopathy in sarcoidosis

Uptake of 18F-fluorodeoxyglucose (FDG) and 11C-methionine (Met) in mediastinum and hilar lymph nodes was studied using PET in 31 patients with sarcoidosis. The aim of our study was to examine whether these different tracers play a differential role in clinical assessment of pulmonary involvement.

METHODS

Fluorine-18-fluorodeoxyglucose and 11C-Met PET were administered on different days. The differential absorption ratio of these tracers was calculated for the region of interest with the highest level of activity. Clinical reassessment of sarcoidosis was made at least 1 yr after the first PET examination. In seven patients whose lymph nodes still remained visible by other imagings at the time of reevaluation, the same PET study was performed again.

RESULTS

Both FDG and Met were accumulated in the lymph nodes in all but one patient. The FDG and Met uptake ratios in all patients were not correlated, but they could be divided into the FDG-dominant group (FDG/Met uptake ratio > or = 2) and the Met-dominant group (FDG/Met uptake ratio < 2). Within each group, the FDG and Met uptake values were correlated. The rate of improvement assessed by clinical status and chest radiographs was considerably higher in the FDG- (78%) than in the Met-dominant group (33%). In the seven patients of the repeated PET examination, their FDG/Met uptake ratios were generally unchanged after 1 yr.

CONCLUSION

The results suggest that the FDG/Met uptake ratio using PET may reflect the differential granulomatous status in sarcoidosis and be a useful tool for pretreatment evaluation.