Petrobasal Vein: A Previously Unrecognized Vein Directly Connecting the Superior Petrosal Sinus with the Emissary Vein of the Foramen Ovale

BACKGROUND AND PURPOSE

The superior petrosal sinus terminates anteriorly at the cavernous sinus and posteriorly at the transverse sinus. Venous variations directly connecting the superior petrosal sinus and the emissary veins of the foramen ovale are not well-recognized. We present a connecting vein, provisionally named the petrobasal vein.

MATERIALS AND METHODS

Biplane cerebral angiography of the bilateral internal carotid arteries and the vertebral artery acquired in 267 patients was retrospectively reviewed by 2 neuroradiologists with special interest in the existence and course of the petrobasal vein.

RESULTS

The petrobasal vein was observed to lie anterior-posteriorly on the superior surface of the petrosal bone and connected to the midportion of the superior petrosal sinus and the emissary veins of the foramen ovale in 41 patients (15%) and sides (7.9%); it drained into the pterygoid plexus. The petrobasal vein was observed on VAG in 21 patients, on ICAG alone in 8 patients (9 sides), on both VAG and ICAG in 12 patients, and on ICAG in 1 patient. In the patients in whom the petrobasal vein was visualized on the ICAs, the superficial middle cerebral vein drained into a combination of the pterygoid plexus via the emissary veins of the foramen ovale and the superior petrosal sinus.

CONCLUSIONS

The petrobasal vein, an unknown vein directly connecting the superior petrosal sinus and the emissary veins of the foramen ovale and draining into the pterygoid plexus, can occasionally be identified on cerebral angiography as a variant drainage route from the cerebellum and brainstem veins and/or from the superficial middle cerebral vein. The petrobasal vein is thought to be a remnant of the primitive tentorial sinus.

Long-range Correlated Glucose Fluctuations in Diabetes

Objectives : Our objective is to investigate diabetes- related alteration of glucose control in diurnal fluctuations in normal daily life by detrended fluctuation analysis (DFA).

Methods : The fluctuations of glucose of 12 non-diabetic subjects and 15 diabetic patients were measured using a continuous glucose monitoring system (CGMS) over a period of one day. The glucose data was calculated by the DFA method, which is capable of revealing the presence of long-range correlations in time series with inherent non-stationarity.

Results : Compared with the non-diabetic subjects, the mean glucose level and the standard deviation are significantly higher in the diabetic group.

The DFA exponent α is calculated, and glucose time series are searched for the presence of negatively (0.5 < α <1.5) or positively (1.5 < α) correlated fluctuations. A crossover phenomenon, i.e. a change in the level of correlations, is observed in the non-diabetic subjects at about two hours; the net effects of glucose flux/reflux causing temporal changes in glucose concentration are negatively correlated in a “long-range" (> two hours) regime. However, for diabetic patients, the DFA exponent α = 1.65 ± 0.30, and in the same regime positively correlated fluctuations are observed, suggesting that the net effects of the flux and reflux persist for many hours.

Conclusions : Such long-range positive correlation in glucose homeostasis may reflect pathogenic mechanisms of diabetes, i.e., the lack of the tight control in blood glucose regulation. Using modern time series analysis methods such as DFA, continuous evaluation of glucose dynamics could promote better diagnoses and prognoses of diabetes and a better understanding of the fundamental mechanism of glucose dysregulation in diabetes.

SU-E-T-497: Study of Restricted Mass Stopping Power Ratio in Small Electron Tube Fields

PURPOSE

Electron tubes with small radii are useful to treat narrow regions which cannot accommodate normal electron applicators. In small electron fields, it is not trivial to estimate restricted mass stopping power ratio (MSR), which is needed to evaluate dose from ion chamber measurement. We studied MSRs in small electron tube fields using the Monte Carlo simulation.

METHODS

Electron tubes with radii, 3 and 2.5 cm, were used in this study. Nominal electron energies were 6 and 9 MeV. There were two types of tubes. One has a normal cut but the other has a 45-degree cut. For the normal cut tube, percent depth dose (PDD) in water was evaluated along the center of axis (CAX) of a beam. For the 45-degree cut tube, PDD was evaluated along the vertical line from the intersection of the CAX and the phantom surface with 45-degree gantry angle. The MSRs and mean electron energies were calculated using the Monte Carlo simulation.

RESULTS

We found good agreement between the measured and calculated PDDs. The changes of mean energies from those in the 10×10 cm² field at the depth of maximum dose (dmax) were very small for the normal cut electron tubes. For the 45-degree cut tubes, the changes of mean energies at dmax were less than 1 MeV. The MSRs in the normal cut tube fields were almost the same as those in the 10×10 cm² field at the corresponding depths. The MSRs for the 45-degree cut tubes deviated from those in the 10×10 cm² by about 1% (1.5 % at most).

CONCLUSIONS

We evaluated the mean energies and MSRs in small electron tube fields. The deviations of them from the values in the 10×10 cm² were small. The maximum difference of MSR was 1.5% in 45-degree cut tube fields. This work was supported by KAKENHI (23791449), Japan Society for the Promotion of Science, and Cancer Professional Training Plan, The Ministry of Education, Culture, Sports, Science and Technology, Japan.

Long-range correlated glucose fluctuations in diabetes

OBJECTIVES

Our objective is to investigate diabetes-related alteration of glucose control in diurnal fluctuations in normal daily life by detrended fluctuation analysis (DFA).

METHODS

The fluctuations of glucose of 12 non-diabetic subjects and 15 diabetic patients were measured using a continuous glucose monitoring system (CGMS) over a period of one day. The glucose data was calculated by the DFA method, which is capable of revealing the presence of long-range correlations in time series with inherent non-stationarity.

RESULTS

Compared with the non-diabetic subjects, the mean glucose level and the standard deviation are significantly higher in the diabetic group. The DFA exponent alpha is calculated, and glucose time series are searched for the presence of negatively (0.5 < alpha < 1.5) or positively (1.5 < alpha) correlated fluctuations. A crossover phenomenon, i.e. a change in the level of correlations, is observed in the non-diabetic subjects at about two hours; the net effects of glucose flux/reflux causing temporal changes in glucose concentration are negatively correlated in a "long-range" (> two hours) regime. However, for diabetic patients, the DFA exponent alpha = 1.65 +/- 0.30, and in the same regime positively correlated fluctuations are observed, suggesting that the net effects of the flux and reflux persist for many hours.

CONCLUSIONS

Such long-range positive correlation in glucose homeostasis may reflect pathogenic mechanisms of diabetes, i.e., the lack of the tight control in blood glucose regulation. Using modern time series analysis methods such as DFA, continuous evaluation of glucose dynamics could promote better diagnoses and prognoses of diabetes and a better understanding of the fundamental mechanism of glucose dysregulation in diabetes.

Maturational changes in skin color of Japanese newborn infants

BACKGROUND/OBJECTIVE

The skin color of newborn infants is subjectively observed to change, depending upon their gestational age. We evaluated the relationship between neonatal skin color and gestational age by employing an objective method.

METHODS

Using a tristimulus photocolorimeter, L*, a*, and b* were examined as the parameters of skin color in Japanese newborn infants (Commission Internationale de l'Eclairage L*a*b* color space). The following items were examined: (1) the reproducibility of the measurements; (2) the time course of the values during the first 24 h after birth, and (3) the relationship with the gestational age. The gestational age of these infants had been determined by measuring their crown-rump length during fetal periods.

RESULTS

Reliability and validity of the measurements were satisfactory for all parameters. However, a* and b* fluctuated widely during the first 24 h. By contrast, L* was stable between 3 and 24 h after birth. L* measured during these periods directly correlated with the gestational age (r=0.843, p<0.0001).

CONCLUSIONS

Because L* represents lightness or darkness, our results suggest that the skin color changes from black to white with maturation. L* may be a helpful parameter for the evaluation of the gestational age of newborn infants.

Paradoxical adaptation of mature radius to unilateral use in tennis playing

The positive effects of physical activity on human bone mass have been well documented in many cross-sectional studies comparing athletes with sedentary controls as well as in longitudinal follow-up. By applying peripheral quantitative computed tomography (pQCT), which has the advantage of measuring volumetric bone mineral density (BMD) and the ability to distinguish among trabecular and cortical components, it was demonstrated that cortical BMD of the dominant arm was not greater than that of the nondominant arm. Cortical drift toward the periosteal direction and an increase in cortical thickness resulted in an improvement of mechanical characteristics of the playing arm's midradius. An improvement in the mechanical properties of young adult bone in response to long-term exercise was therefore related to geometric adaptation, but not to an increase in BMD. The manner in which the recruitment and function of bone cells are coordinated differs between the growing and the nongrowing skeleton. In the former, modeling is the dominant mode, and in the latter it is remodeling. In the present study, the side-to-side difference of 92 middle-aged female tennis players who initiated training after bone had matured was analyzed by pQCT. The side-to-side difference detected suggested a paradoxical adaptation of the mature radius to unilateral use during tennis playing, and that tennis playing after bone had matured did not stimulate cortical drift in the periosteal direction, unlike that seen in young subjects. Unexpectedly, the cross-sectional areas (periosteal and endocortical area) of the radius were smaller in the dominant arm than in the nondominant arm in the middle-aged female players. The findings suggest that unilateral use of the arm after the third decade of life suppresses age-related changes in bone geometry.

Effect of short-term low-intensity exercise on insulin sensitivity, insulin secretion, and glucose and lipid metabolism in non-obese Japanese type 2 diabetic patients

The aim of the present study was to investigate the effects of short-term physical exercise that did not change body mass on insulin sensitivity, insulin secretion, and glucose and lipid metabolism in 39 non-obese Japanese type 2 diabetic patients. Insulin sensitivity and insulin secretion were estimated with homeostasis model assessment insulin resistance (HOMA-IR) and HOMA-B-cell function proposed by Matthews et al., respectively. All patients were hospitalized and were engaged in low-intensity exercise that consisted of walking and dumbbell exercise for successive 7 days. There were no changes in hospital diet and the dose of any medications used throughout the study. Fasting glucose, insulin, and lipids were measured before and after exercise. After exercise, serum triglyceride levels significantly decreased, but no significant changes were observed in total and HDL cholesterol concentrations. Fasting glucose, insulin, and HOMA-IR levels significantly decreased after exercise, but HOMA-B-cell function did not change during the study. There was no significant difference between BMI levels before and after exercise. From these results, it can be concluded that short-term (7 days) low-intensity physical exercise combined with hospital diet reduces serum triglycerides, insulin resistance, and fasting glucose levels without affecting BMI in non-obese Japanese type 2 diabetic patients.

High-power terahertz radiation emitter with a diamond photoconductive switch array

A photoconductive switch-arrayed antenna with a chemical vapor-deposited diamond film was developed to generate high-power terahertz (THz) radiation. With this device, an electric field stress of 2 x 10(6) V/cm can be applied to photoconductive gaps because of the high breakdown threshold of diamond and the overcoated gap structure for the prevention of surface flashover. This level of field stress can alleviate the current problem of saturation in THz emission by use of a photoconductive antenna. The device consists of more than two thousand 20 micron x 2.8 mm emitters. In an experiment using an ultrashort pulse Kr*F laser, we obtained an energy density of 10 microJ/cm(2) on the emitter surface at E = 10(5) V/cm. This density was larger than that of the current large-aperture antenna. There was no severe saturation in photoconductive current up to E = 10(6) V/cm, and a focused intensity of 200 MW/cm(2) can be expected.

Novel dinucleotide repeat polymorphism in the first exon of the STAT-6 gene is associated with allergic diseases

BACKGROUND

T helper-type 2 cytokines, such as interleukin-4 (IL-4) and IL-13, may play a central role in allergic diseases. The protein known as 'signal transducers and activators of transcription 6' (STAT-6) is a key transcription factor involved in both IL-4- and IL-13-mediated biological responses.

OBJECTIVE

The objective of this study was to evaluate the possible role of the STAT-6 gene in modulating atopy in the Japanese population.

METHODS

We screened all 23 exons of the STAT-6 gene from 10 subjects for mutations by direct polymerase chain reaction (PCR) sequencing. The STAT-6 gene polymorphisms were genotyped by PCR fragment length polymorphism analysis and PCR-SSCP analysis. The IL-4 receptor Q576R polymorphism was also examined by PCR-SSCP analysis.

RESULTS

We found a novel dinucleotide repeat polymorphism in the first exon of the STAT-6 gene. The genotypes were classified into four groups according to the number of GT repeats present, from 13 to 16. The frequency of the A1 allele (326 bp, containing 13 repeats of GT) was higher in children with allergic diseases (bronchial asthma, atopic dermatitis and/or food-related anaphylaxis) than controls, although this was not statistically significant (P = 0.0158). In addition, a strong association between the A1 and A3 allele (containing 15 repeats of GT) heterozygote and allergic diseases was identified (P = 0.0002). However, the levels of IgE were not related to the GT repeat polymorphism in the allergic subjects. The GT repeat polymorphism was not associated with the polymorphism in the IL-4 receptor a chain gene (Q576R) and there was no association between the G2964A variant and allergic diseases.

CONCLUSION

This suggests that genetic variation in the STAT-6 gene may be associated with predisposition to allergic diseases.

Acute effects of prostaglandin D2 to induce airflow obstruction and airway microvascular leakage in guinea pigs: role of thromboxane A2 receptors

BACKGROUND

Although prostaglandin D2 (PGD2), a mast cell-derived inflammatory mediator, may trigger allergic airway inflammation, its potency and the mechanism by which it induces airway microvascular leakage, a component of airway inflammation, is not clear.

OBJECTIVE

We wanted to evaluate the relative potency of PGD2 to cause microvascular leakage as compared to airflow obstruction, because both responses were shown to occur simultaneously in allergic airway diseases such as asthma. The role of thromboxane A2 receptors (TP receptors) in inducing these airway responses was also examined.

METHODS

Anesthetized and mechanically ventilated guinea pigs were given i.v. Evans blue dye (EB dye) and, 1 min later, PGD2 (30, 100, 300 or 1,000 nmol/kg). For comparison, the effect of 150 nmol/kg histamine or 2 nmol/kg leukotriene D4 (LTD4) was also examined. Lung resistance (R(L)) was measured for 6 min (or 25 min for selected animals) and the lungs were removed to calculate the amount of extravasated EB dye into the airways as a marker of leakage. In some of the animals, specific TP receptor antagonists, S-1452 (10 microg/kg) or ONO-3708 (10 mg/kg), or a thromboxane A2 synthase inhibitor, OKY-046 (30 mg/kg), was pretreated before giving PGD2.

RESULTS

Injection of PGD2 produced an immediate and dose-dependent increase in RL (peaking within 1 min), which was significant at all doses studied. At 1,000 nmol/kg, PGD2 induced a later increase in R(L), starting at 3 min and reaching a second peak at 8 min. By contrast, only PGD2 at doses of 300 and 1,000 nmol/kg produced a significant increase in EB dye extravasation. The relative potency of 1,000 nmol/kg PGD2 to induce leakage as compared to airflow obstruction was comparable to histamine at most of airway levels, but less than LTD4. Both responses caused by PGD2 were completely abolished by S-1452 and ONO-3708, but not by OKY-046.

CONCLUSION

PGD2 may induce airway microvascular leakage by directly stimulating TP receptors without generating TXA2 in guinea pigs. Microvascular leakage may play a role in the development of allergic airway inflammation caused by PGD2.

Age-dependent relationship between bronchial hyperresponsiveness to methacholine and total serum IgE level in asthmatic children

BACKGROUND

A relationship between nonspecific bronchial hyperresponsiveness and allergic airway inflammation has been reported in children and in adults with asthma, but the relationship in infants with asthma is still unclear.

OBJECTIVE

To evaluate the relationship between bronchial hyperresponsiveness and total serum IgE level throughout childhood. Bronchial reactivity to methacholine from the age of 1 to 16 years was studied by methacholine inhalation challenge using transcutaneous oxygen pressure (tcPO2) monitoring.

METHODS

Two hundred one asthmatic children (boys:girls = 132:69; 7.3+/-4.0 years of age, mean +/- SD) were enrolled in this study. The tcPO2 was measured using a tcPO2 monitor. Serial doses of methacholine were doubled until a 10% decrease in tcPO2 from the baseline was reached. The cumulative dose of methacholine at the inflection point of tcPO2 was considered to represent the bronchial reactivity to methacholine.

RESULTS

There was no relationship between the cumulative dose of methacholine at the inflection point of tcPO2 and total serum IgE level in the group of children aged 1 to 4 years (P = 0.212), but significant correlations were found in the groups aged 5 to 10 years and 11 to 16 years (P = 0.044 and P = 0.014, respectively).

CONCLUSIONS

We conclude that there is an age-dependent relationship between bronchial reactivity to methacholine and the total serum IgE level and that inhaled allergens, which were more common allergens in older children, may have some effects on the degree of bronchial reactivity to methacholine in children with asthma.

Effect of mild exercise training on glucose effectiveness in healthy men

OBJECTIVE

To detect whether mild exercise training improves glucose effectiveness (S(G)), which is the ability of hyperglycemia to promote glucose disposal at basal insulin, in healthy men.

RESEARCH DESIGN AND METHODS

Eight healthy men (18-25 years of age) underwent ergometer training at lactate threshold (LT) intensity for 60 min/day for 5 days/week for 6 weeks. An insulin-modified intravenous glucose tolerance test was performed before as well as at 16 h and 1 week after the last training session. S(G) and insulin sensitivity (S(I)) were estimated using a minimal-model approach.

RESULTS

After the exercise training, VO(2max) and VO(2) at LT increased by 5 and 34%, respectively (P < 0.05). The mild exercise training improves S(G) measured 16 h after the last training session, from 0.018 +/- 0.002 to 0.024 +/- 0.001 min(-1) (P < 0.05). The elevated S(G) after exercise training tends to be maintained regardless of detraining for 1 week (0.023 +/- 0.002 min(-1), P = 0.09). S(I) measured at 16 h after the last training session significantly increased (pre-exercise training, 13.9 +/- 2.2; 16 h, 18.3 +/- 2.4, x10(-5). min(-1). pmol/l(-1), P < 0.05) and still remained elevated 1 week after stopping the training regimen (18.6 +/- 2.2, x10(-5). min(-1). pmol/l(-1), P < 0.05).

CONCLUSIONS

Mild exercise training at LT improves S(G) in healthy men with no change in the body composition. Improving not only S(I) but also S(G) through mild exercise training is thus considered to be an effective method for preventing glucose intolerance.

Relationship between bronchial hyperresponsiveness and development of asthma in children with chronic cough

To evaluate the relationship between bronchial hyperresponsiveness (BHR) and the development of asthma in children with chronic cough, we performed methacholine inhalation challenges and transcutaneous oxygen pressure (tcPO2) measurements in 92 children with chronic cough aged from 1-13 years (55 boys and 37 girls; mean, 5.3 years) and followed them for > or = 10 years. Forty-four age-matched children with asthma (24 males and 20 females; mean, 6.5 years) and 44 age-matched children without cough or asthma served as controls (18 males and 26 females; mean, 4.6 years). Consecutive doubling doses of methacholine were inhaled until a 10% decrease in tcPO2 from baseline was observed. The cumulative dose of methacholine at the inflection point of the tcPO2 record (Dmin-PO2) was considered to represent hyperresponsiveness to inhaled methacholine. After 10 years or more of follow-up, 60 of the 92 subjects with cough answered our questionnaire, and 27/60 had been diagnosed with asthma. There was a statistical difference in Dmin-PO2 between the children who presented with chronic cough originally and who developed asthma (asthma-developed group) and those who did not develop asthma (asthma-free group). There was no difference in the value of Dmin-PO2 between the asthma-developed group and the asthma group, or between the asthma-free group and the age-matched control group. Among the children with chronic cough, there was no difference in Dmin-PO2 between girls and boys, either in the asthma-developed group or in the asthma-group. We conclude that 45% of the children with a chronic cough in early life developed asthma, and that BHR in children with chronic cough during the childhood period is a strong risk factor for the development of asthma.

Identification of allergen fractions of wheat flour responsible for anaphylactic reactions to wheat products in infants and young children

Wheat is a food allergen which occasionally causes anaphylactic reactions exclusively in young children. There is very little knowledge of the clinical outcome in cases of food-related anaphylaxis and the differences in the allergenic protein components of food involved, comparing individuals who have suffered from an anaphylactic reaction with other individuals. The objectives of the present study were to examine the clinical features of 7 young children who had experienced anaphylactic reactions after ingesting wheat flour-containing products, and to analyze the allergens in wheat flour responsible for the anaphylactic symptoms. We measured the total IgE levels and the levels of IgE antibodies specific to wheat flour and performed IgE immunoblotting, comparing the sera from these children with sera from patients with atopic dermatitis. All sera from children who had experienced anaphylactic reactions were found to be positive for IgE specific to wheat. IgE immunoblotting revealed that 3 of these 7 children had sera showing reactivity to components of the salt-soluble protein fraction (16, 35--67 and 94 kD) and salt-insoluble protein-containing fraction (16, 38 and 70 kD) and 4 had no sera showing reactivity to components of the salt-soluble fraction. Patients with atopic dermatitis showed similar staining patterns. Various proteins in wheat flour could be allergens responsible for anaphylaxis and atopic dermatitis in infants or young children. Our findings suggest that these two clinically diverse allergic diseases do not necessarily represent responses to different allergenic proteins of wheat.

Effects of bezafibrate on insulin sensitivity and insulin secretion in non-obese Japanese type 2 diabetic patients

The aim of the present study was to investigate the effect of bezafibrate on insulin sensitivity and insulin secretion in 30 non-obese Japanese type 2 diabetic patients with hypertriglyceridemia (serum triglycerides > 150 mg/dL). Insulin sensitivity was measured with homeostasis model assessment insulin resistance (HOMA-IR) proposed by Matthews et al. HOMA-B-cell function, proposed by Matthews et al validated against minimal model-derived insulin secretion, was used to assess pancreatic insulin function. Twenty-two patients were treated with glibenclimide and the rest were treated with diet alone. All patients were treated with bezafibrate (400 mg/d) for 3 months. There were no changes in diet and the dose of any medications used throughout the study. Fasting glucose, insulin, triglycerides, HDL cholesterol, and total cholesterol levels were measured before and after treatment of bezafibrate. After treatment of bezafibrate for 3 months, serum triglyceride levels significantly decreased from 277 +/- 30 to 139 +/- 9 mg/dL (P <.001) and serum HDL cholesterol levels increased significantly from 45 +/- 2 to 52 +/- 2 mg/dL (P =.003). Serum cholesterol level was unchanged during the study (198 +/- 7 v 201 +/- 7 mg/dL, P =.383). Fasting glucose (163 +/- 8 v 139 +/- 6 mg/dL, P =.006) significantly decreased after the treatment with bezafibrate. HbA1c levels decreased, although not statistically significant (7.50 +/- 0.25 v 7.17% +/- 0.19%, P =.147). On the other hand, fasting insulin (9.3 +/- 0.7 v 7.3 +/- 0.5 microU/mL, P =.010) and HOMA-IR (3.61 +/- 0.24 to 2.53 +/- 0.20, P <.001) levels decreased significantly after the treatment with bezafibrate. In contrast, HOMA-B-cell function did not change during the study (41.4 +/- 5.5 v 41.8 +/- 4.7, P =.478). There was no significant difference in body mass index (BMI) levels before and after the therapy (23.0 +/- 0.4 v 23.1 +/- 0.4 kg/m(2), P =.483). From these results, it can be concluded that bezafibrate reduces serum triglycerides, insulin resistance, and fasting blood glucose levels in non-obese Japanese type 2 diabetic patients.

Relationship between bronchial hyperresponsiveness and development of asthma in wheezy infants

STUDY OBJECTIVES

To evaluate the relationship between bronchial hyperresponsiveness (BHR) in infants with wheezing and the subsequent development of asthma.

INTERVENTION

Bronchial reactivity to inhaled methacholine (BRm) during the infantile period was studied using the transcutaneous partial pressure of oxygen (tcPO(2)) method. Children were followed long-term for the development of asthma.

PATIENTS

Fourteen children with bronchiolitis (mean age, 0.7 years) and 48 with wheezy bronchitis (mean age, 2.3 years) were enrolled. For comparison, 40 children with asthma (mean age, 4.6 years) and 27 healthy control subjects without chronic respiratory disease (mean age, 2.7 years) were studied.

MEASUREMENTS

Consecutive doses of methacholine were doubled until a 10% decrease in tcPO(2) from baseline was reached. The cumulative dose of methacholine (Dmin) at the inflection point of tcPO(2) (Dmin-PO(2)) was recorded.

RESULTS

During > 10 years of follow-up, seven patients with bronchiolitis developed asthma and all patients in the higher BRm set developed asthma, compared with none in the lower BRm set. In the wheezy bronchitis group, Dmin-PO(2) values in the 32 patients who developed asthma were lower than those in patients who had not developed asthma (p < 0.001).

CONCLUSIONS

We concluded that there is a tendency for infants with a clinical diagnosis of bronchiolitis or wheezy bronchitis and who show BHR in the infantile period to develop asthma. The presence of increased BHR after infantile respiratory diseases associated with wheezing may be a prelude to the development of childhood asthma.

Elevated type IV collagen in bronchoalveolar lavage fluid from infants with bronchopulmonary dysplasia

We measured the levels of type IV collagen and lipid peroxides in bronchoalveolar lavage fluid (BALF) from infants with respiratory distress syndrome (RDS) to determine the relationship to the development of bronchopulmonary dysplasia (BPD). We analyzed their levels between two groups, RDS infants who developed BPD (n = 8, BPD group) and those who did not (n = 11, RDS group). The levels of the type IV collagen in the BPD group were significantly higher than those in the RDS group at 3 and 7 days of age (p = 0.0024). In the BPD group, persistently increased levels of the type IV collagen were observed during the period up to 14 days of age. There was a positive relationship between the type IV collagen levels and polymorphonuclear leukocyte counts, and thiobarbituric acid-reactive substance levels in BALF. These results suggest that the increased type IV collagen levels in BALF of BPD infants may reflect pulmonary basement membrane damage and the involvement of oxygen metabolites in its process.

Remnant-like particle cholesterol, triglycerides, and insulin resistance in nonobese Japanese type 2 diabetic patients

OBJECTIVE

The aim of the study was to investigate the relationships between remnant-like particle (RLP) cholesterol, triglycerides, and insulin resistance in nonobese Japanese type 2 diabetic patients.

RESEARCH DESIGN AND METHODS

A total of 86 nonobese Japanese type 2 diabetic patients (72 men and 14 women, aged 40-83 years, BMI 20.1-26.6 kg/m2) were studied. BMI, HbA1c levels, and fasting concentrations of plasma glucose, serum lipids (RLP cholesterol, total cholesterol, HDL cholesterol, and triglycerides), and serum insulin were measured. Insulin resistance was estimated by the homeostasis model assessment (HOMA-IR). The subjects were divided into two groups according to the value of HOMA-IR. Values >2.5 were indicative of the insulin-resistant state, and values <2.5 were indicative of the insulin-sensitive state.

RESULTS

The insulin-resistant group had significantly higher RLP cholesterol and triglyceride levels and lower HDL cholesterol levels compared with the insulin-sensitive group. Univariate regression analysis showed that insulin resistance was positively correlated with BMI (r = 0.254, P = 0.019), HbA1c levels (r = 0.278, P = 0.011), RLP cholesterol levels (r = 0.315, P = 0.004), and triglyceride levels (r = 0.332, P = 0.002) and was negatively correlated with HDL cholesterol levels (r = -0.301, P = 0.006) in our diabetic patients. Multiple regression analysis showed that insulin resistance was independently associated with serum triglyceride levels, which explained 13.5% of the variability of insulin resistance in our nonobese Japanese type 2 diabetic patients.

CONCLUSIONS

These results indicate that 1) nonobese Japanese type 2 diabetic patients with insulin resistance are characterized by high RLP cholesterol and triglyceride levels, and low HDL cholesterol levels; and 2) the level of serum triglycerides is an independent predictor of insulin resistance in these patients.

Bronchial hyperresponsiveness before and after the diagnosis of bronchial asthma in children

OBJECTIVE

To assess at what age bronchial hyperresponsiveness (BHR) is acquired in children with asthma.

BACKGROUND

A relationship between BHR and infantile wheezing diseases has been reported. Infants with a genetic predisposition to atopy are more likely to wheeze with respiratory viral infection or bronchiolitis, and it is suspected that the continued BHR after the first attack of asthma may be induced or triggered by some viral infections. Also, recent studies have reported the existence of atopic and BHR-related genes. However, whether BHR is congenital or acquired after asthma attacks, and when BHR in children with asthma is established or acquired remain unclear.

METHODS

We performed methacholine inhalation challenge using a transcutaneous oxygen pressure (tcPO(2)) monitoring system in 205 children without asthma from 6 months to 6 years of age. During follow-up, 18 of these participants were diagnosed with asthma (group N-A). This group and 15 age-matched children without asthma (group N-N) were tested twice using methacholine inhalation challenge. For comparison, 39 age-matched atopic-type asthmatic children (group A-A) were also given the inhalation challenge twice. Methacholine inhalation challenge using a tcPO(2) monitoring system was performed while the participants were asleep in the supine position. Sequential doses of inhaled methacholine delivered by oxygen mask were doubled until a 10% decrease in tcPO(2) from the baseline was reached. The cumulative dose of methacholine at the inflection point of tcPO(2) (minimal dose of methacholine [Dmin]-PO(2)) was considered to represent BHR.

RESULTS

In groups N-N and A-A, there was no difference in Dmin-PO(2) between the first and second challenge. However, the Dmin-PO(2) in group N-A significantly decreased from the first challenge to the second challenge. There was no significant difference between the Dmin-PO(2) in group N-N and the first Dmin-PO(2) in group N-A; or between the Dmin-PO(2) in group A-A and the second Dmin-PO(2) in group N-A.

CONCLUSIONS

These data suggest that BHR in many infants with asthma is acquired after several asthma attacks.bronchial hyperresponsiveness, childhood asthma, methacholine inhalation challenge, transcutaneous oxygen pressure.

The role of the body mass index and triglyceride levels in identifying insulin-sensitive and insulin-resistant variants in Japanese non-insulin-dependent diabetic patients

Using the minimal model approach shown by Bergman, our group had previously shown 2 variants among non-obese mildly diabetic patients, one with normal insulin sensitivity and the other with insulin resistance. The present study examines whether these 2 variants exist in the ordinary Japanese non-insulin-dependent diabetes mellitus (NIDDM) population and compares the clinical profile between the 2 discrete forms of NIDDM. In addition, we investigated the factors responsible for insulin resistance observed in Japanese NIDDM populations. One hundred eleven untreated Japanese NIDDM subjects (fasting glucose < 10 mmol/L) were assessed for insulin action (homeostasis model assessment [HOMA-IR] = fasting serum insulin (microU/mL) x fasting plasma glucose (mmol/L)/22.5) and the fasting lipid profile. Sixty percent of these patients had normal insulin sensitivity (HOMA-IR < 2.5). The insulin-resistant patients had higher serum cholesterol (188.1 +/- 5.2 v 182.2 +/- 3.9 mg/dL, P> .05) and low-density lipoprotein (LDL) cholesterol (501.2 +/- 16.7 v 469.4 +/- 14.8 mg/dL, P > .05) than the insulin-sensitive patients, but the difference was not statistically significant. In contrast, the former group had a significantly higher body mass index ([BMI] 26.6 +/- 0.8 v 21.7 +/- 0.4 kg/m2, P < .0001) and higher serum triglycerides (181.0 +/- 16.4 (range, 79 to 545) v 95.1 +/- 4.1 (range, 36 to 204) mg/dL, P < .0001) and lower high-density lipoprotein (HDL) cholesterol (47.2 +/- 1.7 v 58.2 +/- 2.5 mg/dL, P < .005) than the latter group. HOMA-IR was related to the BMI. Fifteen of 17 (88%) NIDDM patients with a BMI greater than 27.0 were insulin-resistant, whereas 35 of 38 (92%) NIDDM patients with a BMI less than 21.5 were insulin-sensitive. In the midrange BMI (21.5 to 27.0 kg/m2), patients were equally likely to be insulin-resistant or insulin-sensitive. Analysis of the midrange BMI group showed that HOMA-IR was associated with serum triglycerides (P < .0001) but not with the BMI. These data suggest the following conclusions: (1) Japanese NIDDM patients can be classified into 2 populations, one with normal insulin sensitivity and the other with insulin resistance; (2) NIDDM patients with normal insulin action have a low cardiovascular disease risk factor, whereas those with insulin resistance have a markedly increased cardiovascular disease risk factor; and (3) the BMI and serum triglyceride level per se are associated with insulin action in Japanese NIDDM populations.

Both insulin sensitivity and glucose sensitivity are impaired in patients with non-diabetic liver cirrhosis

Background: Careful nutritional support is required in patients with liver cirrhosis due to their glucose intolerance. To elucidate the mechanism of glucose intolerance in cirrhotics, we measured insulin secretion, whole body insulin sensitivity (SI), and glucose sensitivity (SG) in non-diabetic cirrhotics.Methods: Eight patients with compensated cirrhosis who showed normal fasting blood glucose levels and non-diabetic curves on a 75 g oral glucose tolerance test participated in this study. Four normal volunteers were selected as controls. After an overnight fast, glucose was injected intravenously at 300 mg kg(-1) in 2 min followed 20 min later by intravenous insulin at 0.02 U kg(-1) in 5 min. Sequential blood samples were drawn from 20 min before the glucose injection to 3 h post-injection, and plasma glucose and insulin levels were determined. Plasma glucose and insulin disappearance curves were analyzed using the minimal compartment model, and kinetic parameters, including glucose clearance (KG), insulin secretion, SI and SG, were estimated.Results: KG was slower in cirrhosis than in controls, although not significant (P=0.051). Insulin secretion was not different between the two groups. However, SI was significantly lower in cirrhotics (0.814x10(-4) min(-1) pM(-1); 0.572-1.403x10(-4) min(-1) pM(-1)) as compared to controls (1.643x10(-4) min(-1) pM(-1); 0.678-2.085x10(-4) min(-1) pM(-1)) (P=0.029). SG was also lower in the cirrhosis (0.0154 min(-1); 0.0071-0.0208 min(-1)) than in the control group (0.0211 min(-1); 0.0184-0.0260 min(-1)) (P=0.026).Conclusion: Both SI and SG are already impaired in non-diabetic cirrhotic patients even when KG is minimally delayed and insulin secretion has not yet been affected.

Stimulation of the beta(2) integrin, alpha(M)beta(2), triggers tyrosine phosphorylation and cellular degranulation on human eosinophils

Activation of human eosinophils by specific extracellular stimuli triggers the cellular degranulation response. Because cellular adhesion is critical for this eosinophil degranulation, we have tested the hypothesis that ligation of the beta(2) integrin, alpha(M)beta(2) (Mac-1, CD11b/CD18), leads to intracellular signaling events that contribute to the eosinophil activation response. Recently, we found that engagement of beta(2) integrin using two different approaches, such as cell adhesion induced by IL-5 or direct ligation of alpha(M)beta(2), triggered tyrosine phosphorylation of Cbl, the product of the c-cbl proto-oncogene, paxillin, a cytoskeletal protein, an unidentified 115-kD protein, and subsequent cellular degranulation. The results of this study indicate that engagement of alpha(M)beta(2) on eosinophils triggers an intracellular signaling cascade leading to cellular degranulation. Tyrosine phosphorylation of Cbl, paxillin, and a 115-kD protein may play important roles in adhesion-dependent cellular functions of eosinophils.

Interaction of the effects between vitamin D receptor polymorphism and exercise training on bone metabolism

Bone metabolism is strongly influenced by heredity and environmental factors. To investigate interaction of the effects between vitamin D receptor polymorphism by Fok I and resistance exercise training on bone metabolism, young male subjects with FF genotype (F, n = 10) and Ff or ff genotypes (f, n = 10) followed 1 mo of weight training, and changes in bone metabolism were compared. An additional 14 subjects served as a sedentary control. Biomarkers of bone formation, bone-specific alkaline phosphatase, and osteocalcin were significantly increased by training in both F and f groups. 1, 25-Dihydroxyvitamin D(3), known to upregulate bone formation, was also increased by the training in the f but not in the F group. Bone resorption assessed by cross-linked NH(2)-terminal telopeptide of type I collagen was significantly suppressed by the training, and the decrease in F was greater and longer lasting than that in f group. In conclusion, stimulation of bone formation and suppression of bone resorption occurred within 1 mo in young men. Despite a significant increase in 1,25-dihydroxyvitamin D(3) in the f group but not in the F group, the response of bone metabolism to the training in the F was similar to or greater than that in f group, suggesting a functional difference between vitamin D receptor genotypes f and F.

Pathogenic factors of glucose intolerance in obese Japanese adolescents with type 2 diabetes

We attempted to identify the pathogenic factors involved in the progression to type 2 diabetes in obese Japanese adolescents. Subjects included 18 nondiabetic obese adolescents, 12 obese adolescents with type 2 diabetes on diet therapy, 10 obese adolescents with type 2 diabetes manifesting ketosis at onset or with a history of treatment with hypoglycemic agents, and 26 non-obese adolescent control subjects. The first-phase insulin response (FPIR), glucose disappearance constant (Kg), glucose effectiveness (Sg), and insulin sensitivity (S(I)) were obtained using an insulin-modified frequently sampled intravenous glucose tolerance test (FSIGT) and a minimal model analysis. The disposition index (DI, by FPIR x S(I)) was determined to assess any endogenous insulin effect. The results showed that Kg was decreased significantly (P = .0006) with the progression to severe diabetes in the obese groups. Although S(I) and Sg did not differ significantly among the 3 obese groups, both parameters were significantly lower in each obese group versus the non-obese controls. As a result of the significant decrease in FPIR (P < .0001), the DI decreased (P = .0006) with the progression to severe diabetes in the obese groups. In conclusion, an early manifestation of type 2 diabetes with occasional ketosis at onset may result from beta-cell dysfunction to glucose stimulation. This finding is demonstrated by the relatively low FPIR to decreased S(I) in obese Japanese adolescents, as well as the low Sg as a synergic role in glucose intolerance. The present findings from a Japanese population for pathogenic factors aside from obesity may help us to gain a better understanding of the progression to adolescent, early-onset, obese type 2 diabetes and its severity.

Influence of mild exercise at the lactate threshold on glucose effectiveness

The effect of a single bout of mild exercise on glucose effectiveness (S(G)) and insulin sensitivity (S(I)) was studied in six young male subjects by using a minimal model. An intravenous glucose tolerance test was performed under two conditions as follows: 1) 25 min after a bout of exercise on a cycle ergometer at the lactate threshold level for 60 min (Ex) and 2) without any prior exercise (Con). Leg blood flow (LBF) was also measured by strain-gauge plethysmography simultaneously with blood sampling. S(I) did not significantly change after exercise (18.1 +/- 1.5 vs. 17.7 +/- 1.9 x 10-(5) min/pM), whereas S(G) significantly increased (0.016 +/- 0.002 vs. 0.025 +/- 0.002 min(-1), P < 0.01). The increased blood flow after exercise remained high during the time period for measurement of the glucose disappearance constant and may be a determinant of S(G). The incremental lactate area under the curve until insulin loading was also significantly higher in Ex than in Con (2.6 +/- 0.9 vs. -3.5 +/- 1.5 mM/min, P < 0.05). These results suggest that increased S(G) after mild exercise may be due, at least in part, to increased LBF and lactate production under a hyperglycemic state.

Intracellular signaling pathways in human eosinophil activation: role of a beta2 integrin, alphaMbeta2

Cellular adhesion is crucial roles for eosinophil effector functions such as degranulation. Here, we focused on the role of a beta2 integrin, alphaMbeta2, in intracellular signaling pathways of human eosinophil activation. We found that the ligation of alphaMbeta2 triggers the activation of an intracellular signaling cascade, including protein tyrosine phosphorylation and phosphoinositide turnover, and subsequent cellular degranulation in human eosinophils. These signaling events may play important roles in adhesion-dependent cellular functions of eosinophils.

Difference in airway reactivity in children with atopic vs nonatopic asthma

STUDY OBJECTIVE

To examine the difference in the mechanisms of bronchial hyperresponsiveness (BHR) in nonatopic asthma and in atopic asthma, we studied bronchial reactivity against nonspecific stimuli in children with atopic asthma and nonatopic asthma.

DESIGN AND PARTICIPANTS

Fourteen children with nonatopic asthma, 24 children with atopic asthma, and 20 age-matched controls participated in this study.

MEASUREMENTS

Inhalation challenge was performed by administering progressively doubling doses of methacholine with a continuous inhalation provocation method. The speed of bronchoconstriction to methacholine (Sm) and the speed of reversal of bronchoconstriction to methacholine after inhalation of a beta2-agonist (r-Sm), which was considered to represent the effect of the beta2-agonist, were calculated from the dose-response curve.

RESULTS

The value of Sm was higher in the nonatopic asthma group than in the atopic asthma group and the control group. The value of r-Sm was also higher in the nonatopic asthma group than in the atopic asthma group, but did not differ from that in the control group.

CONCLUSION

These results indicate that bronchial reactivity against methacholine and the beta2-agonist was greater in nonatopic asthma than in atopic asthma, and that the mechanism of BHR in children with nonatopic asthma may differ from that in children with atopic asthma.

[A case of Goodpasture's syndrome with massive pulmonary hemorrhage ameliorated by cyclophosphamide pulse therapy]

A 22-year-old woman was admitted to our hospital for evaluation of fever, renal dysfunction, and a 3-month-history of macrohematuria. Laboratory evaluation revealed proteinuria (1.8 g/day), hypoproteinemia, microcytic microchromic anemia, renal failure (blood urea nitrogen 30.3 mg/dl, serum creatinine 4.0 mg/dl), and positive serum antiglomerular basement membrane (anti-GBM) antibody. Renal biopsy revealed cellular crescents in all 8 glomeruli and partial rupture of the GBM. The interstitium showed severe inflammatory cell infiltration. Immunofluorescent examination revealed linear deposits of IgG and C3 along the GBM. Pulmonary biopsy revealed linear deposits of IgG along the alveolar basement membrane in the immunofluorescent examination. A diagnosis of Goodpasture's syndrome was made because all of the diagnostic criteria were fulfilled. After admission, the patient's renal function deteriorated rapidly. Hemodialysis was started, and the patient was treated with methylprednisolone pulse therapy and oral prednisolone with double filtration plasma pheresis (DFPP). However, her renal function did not improve. On the 30th hospital day, she showed hemoptysis, and a chest X-ray and CT revealed massive bilateral pulmonary hemorrhage. Despite treatment with pulsed methylprednisolone, oral prednisolone (80 mg/day), and DFPP, the pulmonary hemorrhage improved only transiently, worsening again 5 days later. Cyclophosphamide pulse therapy was administered. After this treatment, the patient's pulmonary manifestations and pulmonary hemorrhage improved. At the present time she is on maintenance dialysis therapy without pulmonary manifestations. These findings suggest that cyclophosphamide pulse therapy is effective against Goodpasture's syndrome with massive pulmonary hemorrhage showing resistance to other conventional therapy.