Which is a real valuable screening tool for lung cancer and measure thoracic diseases, chest radiography or low-dose computed tomography?: A review on the current status of Japan and other countries

Chest radiography (CR) has been used as a screening tool for lung cancer and the use of low-dose computed tomography (LDCT) is not recommended in Japan. We need to reconsider whether CR really contributes to the early detection of lung cancer. In addition, we have not well discussed about other major thoracic disease detection by CR and LDCT compared with lung cancer despite of its high frequency. We review the usefulness of CR and LDCT as veridical screening tools for lung cancer and other thoracic diseases. In the case of lung cancer, many studies showed that LDCT has capability of early detection and improving outcomes compared with CR. Recent large randomized trial also supports former results. In the case of chronic obstructive pulmonary disease (COPD), LDCT contributes to early detection and leads to the implementation of smoking cessation treatments. In the case of pulmonary infections, LDCT can reveal tiny inflammatory changes that are not observed on CR, though many of these cases improve spontaneously. Therefore, LDCT screening for pulmonary infections may be less useful. CR screening is more suitable for the detection of pulmonary infections. In the case of cardiovascular disease (CVD), CR may be a better screening tool for detecting cardiomegaly, whereas LDCT may be a more useful tool for detecting vascular changes. Therefore, the current status of thoracic disease screening is that LDCT may be a better screening tool for detecting lung cancer, COPD, and vascular changes. CR may be a suitable screening tool for pulmonary infections and cardiomegaly.

Evaluation of chest radiography and low-dose computed tomography as valuable screening tools for thoracic diseases

BACKGROUND

Recent studies have shown that low-dose computed tomography (LDCT) is effective for the early detection of lung cancer. However, the utility of chest radiography (CR) and LDCT for other thoracic diseases has not been as well investigated as it has been for lung cancer. This study aimed to clarify the usefulness of the veridical method in the screening of various thoracic diseases.

METHODS

Among individuals who had received general health checkups over a 10-year period, those who had undergone both CR and LDCT were selected for analysis. The present study included 4317 individuals (3146 men and 1171 women). We investigated cases in which abnormal opacity was detected on CR and/or LDCT.

RESULTS

A total of 47 and 124 cases had abnormal opacity on CR and LDCT, respectively. Among these, 41 cases in which the abnormal opacity was identified by both methods contained 20 treated cases. Six cases had abnormalities only on CR, and none of the cases required further treatment. Eighty-three cases were identified using LDCT alone. Of these, many cases, especially those over the age of 50 years, were diagnosed with thoracic tumors and chronic obstructive pulmonary disease, which required early treatment. In contrast, many cases of pulmonary infections have improved spontaneously, without any treatment.

CONCLUSION

These results revealed that LDCT allowed early detection of thoracic tumors and chronic obstructive pulmonary disease, especially in individuals over the age of 50 years. CR is still a useful imaging modality for other thoracic diseases, especially in individuals under the age of 49 years.

Large scale replication analysis of loci associated with lipid concentrations in a Japanese population

BACKGROUND

Recent genome wide association studies discovered seven novel loci that influence plasma concentrations of triglycerides, high density lipoprotein (HDL) and low density lipoprotein (LDL) cholesterol in Europeans. To date, large scale replication studies using populations with known differences in genome-wide linkage disequilibrium (LD) pattern have not been undertaken.

METHODS

To address this issue, we tested associations between single nucleotide polymorphisms (SNPs) within the seven novel loci and plasma lipid profiles in 21 010 Japanese individuals.

RESULTS

Multiple linear regression analyses showed that the rs3812316 in MLXIPL was strongly associated with triglyceride concentrations (p approximately 3.0x10(-11), 7.1 mg/dl decrease per minor C allele) and that rs599839 in CELSR2/PSRC1/SORT1 was strongly associated with LDL cholesterol concentrations (p approximately 3.1x10(-11), 4.7 mg/dl decrease per minor G allele) in the Japanese population. SNPs near ANGPTL3, TRIB1 and GALNT2 showed evidence for associations with triglyceride concentrations (3.6x10(-6)<p<5.1x10(-5)). SNP near TRIB1 showed association with LDL cholesterol concentrations (p approximately 1.2x10(-5)). On the other hand, SNPs in NCAN/CILP2/PBX4 and MVK/MMAB were not associated with any plasma lipid profiles in the Japanese population. Ethnic differences in LD pattern would explain the lack of association between these two loci and plasma lipid concentrations in the Japanese population.

CONCLUSION

Associations between the novel loci and plasma lipid concentrations were generally conserved in the Japanese population, with the exception of NCAN/CILP2/PBX4 and MVK/MMAB.

Identification of the core protein carrying the Tn antigen in mouse brain: specific expression on syndecan-3

We isolated glycoproteins carrying the Tn antigen, which was expressed spatiotemporally in the developing mouse brain. The Tn antigen was expressed on two molecular species with a molecular weight from 200 to 350 kDa and 110 to 160 kDa, as judged on SDS-PAGE. Although the two glycoproteins showed different susceptibilities to heparitinase I and solubilities in a salt solution, after treatment with V8 protease they showed the same mobility corresponding to a molecular weight of 90 kDa on SDS-PAGE, suggesting that these two molecules shared a common core protein. Partial N-terminal sequences of the glycoproteins were determined, i.e. AQRXRNENFERPV and ALAAPXAPAMLP, which were identified as the sequences of the N-terminal and central portions of syndecan-3, respectively. Both glycoproteins were reactive to anti-mouse syndecan-3 antibody. These results suggest that one is a soluble syndecan-3 cleaved between mucin-like domain and transmembrane domain, and the other is a membrane-bound syndecan-3 lacking N-terminal glycosaminoglycan attachment sites, and that both glycoproteins have a mucin-like domain characteristic of syndecan-3, in which the Tn antigen may be expressed.

Developmental expression of a unique carbohydrate antigen, Tn antigen, in mouse central nervous tissues

Using an anti-Tn monoclonal antibody, the Tn antigen was detected immunohistochemically in prenatal and early postnatal central nervous tissues. On embryonic day 9 (E9), the antigen was distributed throughout the single neuroepithelial layer in the neocortex and then became more prominent in the preplate than in the ventricular zone along with formation of the preplate. Following division of the preplate and concomitant formation of the cortical plate, distinct labeling of the neocortex occurred in the marginal, subplate and intermediate zones, whereas in the cortical plate and ventricular zone were virtually not immunostained. It is notable that thalamocortical afferent fibers were also immunostained specifically on E14. After birth, the localization of the antigen became less noticeable and by 3 weeks after birth, the antigen had substantially disappeared. In the developing cerebellum, prominent labeling was also observed in the molecular layer and outskirts of the cerebellar nuclei on early postnatal days. To characterize the glycoprotein bearing the Tn antigen biochemically, immunoblot analysis was performed. The glycoprotein, most of which was extracted with a salt solution, migrated as a broad smeared band corresponding to a molecular weight of about 250 kDa on SDS-PAGE. Among the various tissues examined, this glycoprotein was only detected in the brain and its amount increased until an early postnatal stage with a peak on postnatal day 3 (P3), and then decreased gradually with age. This spatially and developmentally regulated expression of the Tn antigen suggests that this antigen plays a significant role in brain development.

Accidents associated with bathing in home care services for the aged in Japan

OBJECTIVES

To reveal what kinds of accidents happen associated with bathing in home care services for the aged in Japan.

METHODS

The study was cross-sectional in design. In November 1999, a postal questionnaire survey was conducted of 828 councils selected from the list of the National Council of Social Welfare of Japan by a systematic sampling method (extraction rate was 25%). The main outcome measures were characteristics of cases of accidents associated with bathing service for the aged, including patient age, sex, time of occurrence, symptoms, and results of accidents.

RESULTS

Replies were received from 683 (82%) councils. Of the councils that replied, 430 (63%) reported providing bathing service for the aged. Of these 430 councils, 108 (25%) have experienced accidents, and 130 cases were analyzed. Affected patients had a mean age of 80.7 years (SD: 9.0 years), and 71 were females (55%). Sixty-two (48%) had symptoms of a disease or had accidents after bathing, and 42 (32%) presented with loss of consciousness. In results of accidents, 14 (11%) were reported to have died.

CONCLUSION

This study revealed that there were not a few accidents associated with bathing in home care services for the aged in Japan, the most frequent symptom was loss of consciousness, most accidents occurred after bathing, and that some patients died as a result of bathing provided by home care services.

[A study of mental health in community-dwelling older persons--influence of cared elderly]

This study aimed to evaluate mental health of elderly persons living in the community and understand the various backgrounds and effects of care giving. The study used a questionnaire from similar to the one used by Matsubayashi et al in the Kahoku-cho study. The Japanese Version of General Health Questionnaire 12 (GHQ-12) was used to evaluate mental health. Responses were received from 2,799 (81.5%) of 3,432 Numura-cho residents (81.5%). After removing inadequate responses, 1,268 (36.9%) (575 men and 693 women) were analyzed. Fifty-five men (9.6%) and 69 women (10.0%) were caring for someone at home. Multiple logistic regression analysis which examined the relation between mental health and the background factors such as having someone to care for, revealed that their mental health was significantly poor compared to those having no one to care for (odds ratio (OR) = 2.01, 95% confidence interval (CI), 1.29-3.15). As for the relation between the degree of care giving and their mental health, the subjective burden was significantly poor at 72-100% (OR = 3.40, 95% CI, 1.71-6.78) and for those with three to eight years of care-giving (OR = 2.22, 95% CI, 1.00-4.90), disabled activity of daily living (almost bed ridden) of the cared for person (OR = 5.53, 95% CI, 2.23-13.7), severely demented state (OR = 5.13, 95% CI, 2.14-12.3), their mental health was significantly poor. However, being able to participate in an event (OR = 0.12, 95% CI, 0.03-0.49) and strong emotional support (OR = 0.12, 95% CI, 0.03-0.49) were negatively associated with caregivers' psychiatric distress. Having someone to care for largely affected mental health of the elderly to subjects living in the community. Services should be devised to serve the needs such as psychological care of care-givers as well as those being cared for.

Possible contaminant origins of the red cosmetics decorating ancient burial sites in Japan

Marker elements were estimated from the red cosmetics collected from different ancient burials and mine ruins in three separate districts of Japan. Element levels were displayed in reference to the relative amount to sulfur (RA/S), by which the cosmetics were divided into five types: I--a low Hg/S with a low Fe/S; II--both moderate Hg/S and Fe/S; III--a moderate Hg/S with a high Fe/S; III 2--a high Hg/S with a moderate Fe/S; IV--a high Hg/S with a high Fe/S. The cosmetics can be further characterized by referring to other contaminants such as Zn, Cu, and Mn. These combined analyses with contaminant metals were capable of characterizing the origins of the cosmetics; it is useful to compare them to each other. The cosmetics were identified as being due to several groups of contaminants from ancient mines in Japan, and also with this system analysis of the markers it is possible to identify them from neighboring countries.

Methacholine bronchial hyperresponsiveness in chronic sinusitis

The coexistence of chronic sinusitis (CS) may deteriorate the clinical condition of lower airway diseases such as bronchial asthma (BA) or chronic bronchitis (CB). However, the bronchial hyperresponsiveness (BH) in CS without any apparent lower airway disease is not fully understood nor are the effects of treatment. We examined lower airway hyperresponsiveness to methacholine (MCh) in 42 subjects with CS but without allergic rhinitis (AR) who had normal lung functions without any pulmonary symptoms, comparing it with that of 50 subjects with stable BA, 50 subjects with simple CB and 40 subjects with AR, and further examined the effect of endoscopic sinus surgery in 7 CS subjects with BH. The BH to MCh was measured in terms of the minimum dose (Dmin), defined as the cumulative dose at the point where respiratory conductance began to decrease. A Dmin <50 units was defined as BH. Seventy-one percent of CS subjects showed BH without relation to the severity or duration of CS, or atopic status. BH in CS subjects, which was less than that in BA subjects, was similar to that in simple CB or AR in both its prevalence and degree. After the surgical treatment of CS, BH significantly decreased (p < 0.01) with improvements in both nasal symptoms and sinus lesions. These findings suggest that CS itself induces BH to a degree similar to simple CB and AR without any relationship to the clinical background, and that adequate treatment of CS reduces BH.

Japanese paediatricians' judgement of the appropriateness of bathing for children with colds

OBJECTIVES

This study investigated the decisions which Japanese paediatricians make regarding bathing a child with a common cold.

METHODS

A total of 486 printed questionnaires were mailed to paediatricians systematically sampled from the list of members of the Japanese Pediatric Association. The questionnaire included two main questions. (i) Do you permit a 2- to 4-year-old child with a common cold to take a bath? (ii) If the answer to (i) was 'yes', what conditions should limit bathing of such children, and if the answer was 'no', why do you forbid bathing? In addition, the questionnaire included the age and sex of the practitioner, and the type and location of the practice.

RESULTS

A total of 269 paediatricians returned questionnaires (response rate 55%); of these, 88% permitted a child with a cold to take a bath. Of these paediatricians, 5% permitted it without any conditions. The main conditions for taking a bath indicated by these paediatricians were 'no fever' (72%), 'not in a severe physical condition' (27%) and 'after 2 or 3 days from onset' (19%). Thirty-nine paediatricians indicated a specific body temperature at which bathing was appropriate. One-third of these paediatricians did not permit bathing at body temperatures above 38 degrees C. Of the 31 paediatricians (12%) who answered that a child with a cold should not take a bath, 61% were concerned for the physical well-being of the child. However, 29% provided no supporting evidence.

CONCLUSIONS

Japanese paediatricians' judgements concerning bathing of a child with a cold are related to the effects of bathing on physical condition. Bathing immersed up to the neck does not always affect physical conditions. It is necessary to establish appropriate parental and patient education concerning bathing of children with colds.

Participation of syndecan 2 in the induction of stress fiber formation in cooperation with integrin alpha5beta1: structural characteristics of heparan sulfate chains with avidity to COOH-terminal heparin-binding domain of fibronectin

The present study provides direct evidence that syndecan 2 participates selectively in the induction of stress fiber formation in cooperation with integrin alpha5beta1 through specific binding of its heparan sulfate side chains to the fibronectin substrate. Our previous study with Lewis lung carcinoma-derived P29 cells demonstrated that the cell surface heparan sulfate proteoglycan, which binds to fibronectin, is syndecan 2 (N. Itano et al., 1996, Biochem. J. 315, 925-930). We here report that in vitro treatment of the cells by antisense oligonucleotide for syndecan 2 resulted in a failure to form stress fibers on fibronectin substrate in association with specific suppression of its cell surface expression. Instead, localization of actin filaments in the cytoplasmic cortex occurred. A similar response of the cells was observed when the cells were treated to eliminate functions of cell surface heparan sulfates, including exogenous addition of heparin and pretreatment with anti-heparan sulfate antibody, F58-10E4, and with proteinase-free heparitinase I. Size- and structure-defined oligosaccharides prepared from heparin and chemically modified heparins were utilized as competitive inhibitors to examine the structural characteristics of the cell surface heparan sulfates involved in organization of the actin cytoskeleton. Their affinity chromatography on a column linked with a recombinant H-271 peptide containing a C-terminal heparin-binding domain of fibronectin demonstrated that 2-O-sulfated iduronates were essential for the binding. Inhibition studies revealed that a heparin-derived dodecasaccharide sample enriched with an IdoA(2OS)-GlcNS(6OS) disaccharide completely blocked binding of the syndecan 2 ectodomain to immobilized H-271 peptide. Finally, the dodecasaccharide sample was shown to inhibit stress fiber formation, triggered by adhesion of P29 cells to a CH-271 polypeptide consisting of both the RGD cell-binding and the C-terminal heparin-binding domains of fibronectin in a fused form. All these results consistently suggest that syndecan 2 proteoglycan interacts with the C-terminal heparin-binding domain of fibronectin at the highly sulfated cluster(s), such as [IdoA(2OS)-GlcNS(6OS)](6) present in its heparan sulfate chains, to result in the induction of stress fiber formation in cooperation with integrin alpha5beta1.

[Happiness and background factors in community-dwelling older persons]

In order to maintain and improve mental health of elderly people living in the community, a cross sectional survey was conducted to elucidate their happiness and background factors. The subjects were elderly persons living in the community who were able to fill in the questionnaire themselves. The study employed the self-recording questionnaire forms used in Kahoku Longitudinal Aging Study by Matsubayashi et al. Happiness was assessed using a visual analogue scale. Out of 2,379 elderly persons who were able to fill in the questionnaire by themselves in 2,361 (99.2%) returned the questionnaire sheets. After removing inadequate responses, analysis was possible for 1,873 (78.7%) (860 men (average age 72.7 years) and 1,013 women (average age 72.8 years). Among those with greater happiness, the ratio of those living with others (p = 0.0051) was high as well as those with spouses (p = 0.0240), without a history of hypertension (p = 0.0096) and apoplexy (p = 0.0039), not receiving medication regularly (p = 0.0039), with regular habit of walking (p < 0.001), or with work (p < 0.001). As for the relationship between happiness and various scores, the higher the happiness scale became, the scores for ADL, information-related function, functional and emotional support network, healthy condition, appetite condition, sleep condition, memory condition, family relationships, friendship, economic condition became significantly higher (p < 0.001, respectively). On multiple regression analysis using the background factors for happiness as explanatory variables, factors such as functional support network (p < 0.001), emotional support network (p = 0.0254), healthy condition (p < 0.001), good memory condition (p = 0.0027), friendship (p < 0.001), good economic condition (p < 0.001) were significant independent contributing factors. As for the relation between SDS and happiness, the more serious the SDS score (higher score) became, the scores for the feeling of happiness became significantly smaller (p < 0.001). For amelioration of the happiness of elderly persons living in the community, attempts should be made to improve the background factors clarified by the present study by efficiently utilizing health, medical and welfare services.

[A study of depressive state and background factors in community-dwelling older persons]

In order to maintain and improve the mental health of elderly people living in the community, a cross-sectional survey was conducted to elucidate their depressive state and its background factors. Subjects were elderly persons living in the community who were able to fill in the questionnaire themselves. The study used the self-recording questionnaire sheets used in the Kahoku Longitudinal Aging Study by Matsubayashi et al and the Zung Self-rating Depression Scale (SDS). Out of 2,379 elderly persons who were able to fill in the questionnaire by themselves in the community, 2,361 (99.2%) returned the questionnaire sheets. After removing inadequate responses, analysis was possible for 1,181 (49.6%) (542 males (average age 72.3 +/- 5.5) and 639 females (average age 73.0 +/- 6.3). Degree of depressive state as evaluated by SDS was normal for 731 persons (61.9%); mild, 240 (20.3%); moderate, 181 (15.3%); and severe, 29 (2.5%). The average age became higher as the SDS became high, of being indicating the seriousness of the depressive state (p = 0.0155), with the ratio women significantly higher (p = 0.0077). Among those with severe SDS, the ratio of single persons was high (p < 0.001) as well as those who were non-drinkers (p = 0.0015), without regular habit of walking (p < 0.001), or without work (p < 0.001). The ratio of those receiving medication regularly was also significantly high (p = 0.0022). As for the relation of SDS with various of the scores, the higher the SDS score became, the scores for ADL, information-related function, functional and emotional support network, family relationship, friendship, economic condition became significantly lower (p < 0.001, respectively). In logistic regression analysis using the background factors for SDS as explanatory variables, factors such as being women (odds ratio, 1.73; 95% confidence interval, 1.10-2.72). ADL (0.80; 0.69-0.93), emotional support network (0.88; 0.81-0.96), friendship (0.98; 0.96-0.99) were significant independent contributing factors. As for the relation between SDS and subjective senses, the more serious the SDS score became, the scores for feelings of healthiness and satisfaction became significantly smaller (both p < 0.001). For prevention and amelioration of the depressive state of elderly persons living in the community, attempts should be made to improve the background factors which were clarified by the present study by efficiently utilizing health, medical and welfare services and following the future course with a positive attitude.

The role of alcohol dehydrogenase 2 and aldehyde dehydrogenase 2 genotypes in alcohol-induced vasospastic angina

Alcohol ingestion often provokes attacks in patients with vasospastic angina. Type 2 aldehyde dehydrogenase (ALDH2) deficiency, which is based on a single point mutation (Glu487Lys) of the ALDH2 gene, is common in the Japanese population, but rare among the Caucasian population. We investigated how the genotype of ALDH2 affects the characteristics of alcohol-induced vasospastic angina. Ninety-one patients with vasospastic angina who had ingested alcohol daily or occasionally were studied. Patients had been diagnosed as vasospastic angina by a provocation test with an intracoronary injection of ergonovine or acetylcholine during coronary angiography. The Glu487Lys mutation was detected by allele specific PCR. We interviewed the patients to obtain information concerning the relationship between alcohol ingestion and anginal attacks. Alcohol ingestion induced attacks in 16 of 66 patients without the Glu487Lys mutation, 8 of 22 in heterozygotes, and 1 of 3 in mutant homozygotes. The intervals between alcohol ingestion and the onset of anginal attacks were shorter in homozygotes (0.17 hours) and heterozygotes (1.5+/-0.6 hours) for ALDH2*2 than in normal homozygotes for ALDH2*1 (5.4+/-0.6 hours). The amount of ethanol which induced attacks was significantly greater in normal homozygotes than in homozygotes (11 ml) and heterozygotes (42.5+/-7.1 ml) for ALDH2*2 (96.1+/-13.4 ml in normal patients). The frequency of anginal attacks induced by alcohol ingestion did not differ between ALDH deficient and normal homozygotes. In ALDH deficient patients, however, anginal attacks were induced by a smaller amount of alcohol immediately after its ingestion. Thus, the ALDH2 genotype modifies the characteristics of the anginal attacks as a co-factor for the induction of vasospastic angina after alcohol ingestion.

A study of clinical features and treatment of acute bronchitis by Japanese primary care physicians

OBJECTIVE

This study aimed to examine the factors affecting prescription of antibiotics for acute bronchitis in ambulatory care settings in Japan.

METHOD

A prospective study was conducted on 92 physicians engaged in primary care regarding their prescription behaviour for a series of 20 new patients with acute respiratory diseases seen during November 1996 and the background factors affecting the behaviour.

RESULTS

A total of 1755 patients were registered during the study period, 302 (17.2%) of whom were diagnosed with acute bronchitis and 1165 (66.4%) with upper respiratory tract infection. Independent background factors related to diagnosis of acute bronchitis included self-care prior to visit (odds ratio 1.93, 95% CI 1.33-2.80), complaints such as cough (8.80, 4.77-16.2), sputum (2.24, 1.59-3.14) and purulent sputum (6.47, 3.02-13.9). The odds ratio was high in patients with more severe findings of the chest (5.00, 3.64-6.85), given chest X-ray (2.68, 1.33-5.38) while it was low in those feeling cold (0.68, 0.48-0.96), and those with a sore throat (0.63, 0.45-0.90), nasal symptoms (0.75, 0.54-1.04) and more severe findings of the pharynx (0.74, 0.58-0.92). In those with an upper respiratory tract infection, the odds ratio was high for complaints such as feeling cold (1.51, 1.11-2.05) and nasal symptoms (1.39, 1.04-1.86), while it was low for complaints such as cough (0.67, 0.48-0.95), sputum (0.43, 0.30-0.62), purulent sputum (0.19, 0.08-0.44), wheeze (0.34, 0.13-0.92), in those with more severe findings of the tonsil (0.36, 0.29-0.44) and the chest (0.30, 0.19-0.47) and given chest X-rays (0.29, 0.12-0.66). For acute bronchitis, antibiotics were administered to 67.5% and symptomatic therapy concurrently given to 64.9%. As for independent background factors related to prescription of antibiotics for acute bronchitis, the odds ratio was higher in physicians denying the efficacy of antibiotics for treating a cold (4.58, 1.94-10.8), and the patients with complaints such as purulent sputum (22.9, 2.66-197.2), more severe findings of the pharynx (2.26, 1.34-3.79) and of the chest (2.73, 1.53-4.88), and those who had a body temperature measurement taken (4.42, 1.71-11.4) and a chest X-ray (6.11, 1.07-34.9), but was lower in those complaining of chills (0.16, 0.04-0.66) and diarrhoea (0.11, 0.01-1.11).

CONCLUSIONS

A majority of patients receiving medical care for acute bronchitis are given an unnecessary antibiotic prescription. The result of this study may be useful for the finding of appropriate forms of intervention for changing physicians' prescription behaviour.

An association of human T-cell lymphotropic virus type I infection with vascular dementia

Subjects ranging in age from 50 to 89 years old, either with or without dementia were studied by both ELISA for anti-human T-cell lymphotropic virus type I (HTLV-I) gag 100-130 antibody and by cranial CT in order to clarify the relationship between HTLV-I infection and dementia. The frequency of anti-HTLV-I antibody was found to be significantly higher in the patients with dementia (24/130, 18.5%) than in those without dementia (11/139, 7.9%) (P=0.0169). Among the various types of dementia, HTLV-I seropositivity was found to be significantly associated with vascular dementia (11/48, 23%) (P=0.0087), but not with Alzheimer type dementia. In addition, HTLV-I seropositivity was also associated with Babinski sign, and the severity of cerebral infarction, ventricular dilatation and periventricular lucency on CT. The presence of HTLV-I therefore appears to be one of the risk factors for vascular dementia in HTLV-I endemic areas.

[A case of thymic cyst differentiated from cardiac cyst with immunostaining]

This is a case of a 70-year-old woman with thymic cyst which was found by chance on admission for treatment of acute bronchial asthma and diagnosed by pathological examination. After remission of the asthma she was asymptomatic and no pathological physical findings were found except of cervical thyroid tumor of adenomatous goiter. Chest X-ray films revealed a large mediastinal mass with a sharp margin at the right cardiophrenic angle. Chest CT and MRI revealed that it occupied a space from upper anterior mediastinum to right cardiophrenic angle, and that it showed low density area without enhancement, suggesting a mediastinal cyst. A multilocular cyst, 15 cm in diameter, containing serous liquid was excised using thoracotomy. Pathological and immunohistochemical examination of the cyst revealed that its inner surface was lined with benign cylindrical epithelium and that thymic tissues existed in the walls of the cyst, resulting in a thymic cyst. The thymic cyst, of which reports have increased, should be considered in the differential diagnosis of anterior mediastinal cysts.

The case fatality rate of methicillin-resistant Staphylococcus aureus (MRSA) infection among the elderly in a geriatric hospital and their risk factors

From April 1991 to March 1993, there were 49 elderly patients with methicillin-resistant Staphylococcus aureus (MRSA) infection in a geriatric hospital in Fukuoka, Japan. The retrospective study was carried out in order to evaluate the various factors which may influence the case fatality rate of MRSA infection among the elderly. Among them, 33 patients (67.3%) died while only 16 patients became culture-negative for MRSA and discharged after recovering from MRSA infection. A univariate analysis revealed that male sex (odds ratio [OR] = 12.25, 95% confidence interval [CI] = 2.80-53.55), hypoalbuminemia (OR = 3.83, 95% CI = 1.11-13.21) and an excessive usage of antibiotics (OR = 6.67, 95% CI = 1.70-26.09) were risk factors for death among the patients with MRSA infection. In a multivariate analysis, male sex and an excessive usage of antibiotics were still risk factors while hypoalbuminemia was not. However, hypoalbuminemina was more common in male patients than female patients (78.3% vs. 42.3%, p < 0.05). These findings suggest that the case fatality rate of MRSA infection may be high and also suggest that the elderly with MRSA infection who had hypoalbuminemia and/or received many antibiotics may have a poor prognosis.

[The efficacy of HFJV (high frequency jet ventilation) for ARDS (adult respiratory distress syndrome) following total arch replacement]

A 40-year-old man was admitted to the hospital with shock due to acute aortic dissection (type A of Stanford classification). The emergent total arch replacement was performed with the retrograde cerebral perfusion uneventfully. At the 3rd day after the operation, bilateral infiltrates were recognized on the frontal chest radiograph. The oxygenation was gradually decreased to less than 200 mmHg of PaO2/FiO2 in proportion with the growth of infiltrates and increase of LDH in blood. Steroid therapy was not effective. So then HFJV was introduced to improvement of hypoxygenation at the 16th day after the operation. HFJV made PaO2/FiO2 improve immediately to more than 300 mmHg and the inspiratrory pressure decrease to less than 30 mmHg. Bilateral infiltrates were diminished by HFJV. LDH in blood decreased apparently. HFJV had been used together during 15 days. The respirator was weaned at the 46th day after the operation. In this clinical course, the change of PaO2/FiO2 had the negative correlation with that of LDH in blood.

[Six patients in whom exacerbation of asthma was complicated by mediastinal emphysema]

We encountered 6 patients with bronchial asthma complicated by mediastinal emphysema. Their average age was 21 years. All were atopic and had histories of asthma in childhood. In 5 of the 6, mediastinal emphysema developed when the patients had upper respiratory infections. In 3, the mediastinal emphysema worsened. After insertion of subcutaneous drains to decrease intramediastinal pressure, the conditions of those 3 patients improved remarkably. The conditions of the other 3 improved after medication only. During the period of this study, 1.24% of all patients treated at Hiroshima Asa Citizen's Hospital for exacerbations of asthma had mediastinal emphysema.

Risk factors for methicillin-resistant Staphylococcus aureus (MRSA) infection in a Japanese geriatric hospital

A case control study on MRSA infection was carried out, with the purpose of evaluating the effect of age, gender, hypoalbuminemia, the limitation of activities of daily living (ADL), the administration of antibiotics and the use of the new cephems which include third generation cephalosporins and monobactam and carbapenems, on the occurrence of MRSA infection among the inpatients in a geriatric hospital. From April 1991 to March 1994, 285 patients underwent a bacterial culture in the various clinical aspects. 118 patients were positive for MRSA, who were then used as cases while 167 patients who were negative for MRSA were used as controls. The level of serum albumin and the ADL score were lower in the MRSA group than in the non-MRSA group (P < 0.01) while the number of antibiotics administered before bacterial culture was greater in the MRSA group than in the non-MRSA group (P < 0.01). The third generation cephems were more commonly used in the MRSA positive patients than the negative patients (P < 0.01). Even after controlling for the other factors, hypoalbuminemia (OR = 1.73, 95% CI = 1.27-2.36), the limited ADL (partially limited vs without limitation: OR = 1.88, 95% CI = 1.19-2.96, completely limited vs without limitation: OR = 2.50, 95% CI = 1.64-3.82), the use of antibiotics other than the third generation cephems (vs without antibiotics: OR = 1.73, 95% CI = 1.20-2.50) and the administration of the third generation cephems (vs without antibiotics: OR = 3.12, 95% CI = 2.16-4.50) increased the risk of MRSA infection.

Incidence of methicillin-resistant Staphylococcus aureus (MRSA) isolation in a skilled nursing home: a third report on the risk factors for the occurrence of MRSA infection in the elderly

A case control study was carried out in order to evaluate the various factors which may influence the occurrence of methicillin-resistant Staphylococcus aureus (MRSA) infections in a skilled nursing home. From April 1991 to March 1994, bacterial cultures were performed in 55 out of 102 residents in a nursing home based on various clinical aspects. We divided 102 residents into following three groups; (1) the MRSA group (n = 10), residents whose materials for bacterial culture were positive for MRSA, (2) the non-MRSA group (n = 45), residents whose specimens were negative for MRSA but positive for other bacteria, (3) the control group (n = 47), residents who did not have to undergo a bacterial culture because they were free from moderate and severe infectious diseases. Compared with the control group, the activities of daily living score and the serum albumin level were significantly lower in the MRSA group and the non-MRSA group at the beginning of the study. In contrast, the number of antibiotics used prior to the bacterial culture and the proportion of hospitalization within 6 months prior to the bacterial culture were significantly larger in the MRSA group than in either the non-MRSA group, or the control group. These results thus suggest that a low activities of daily living score, the use of many kinds of antibiotics and a recent previous hospitalization may be risk factors of MRSA infection in a nursing home environment.

Phosphorylation of a membrane-intercalated proteoglycan, syndecan-2, expressed in a stroma-inducing clone from a mouse Lewis lung carcinoma

We previously reported that a mouse Lewis lung carcinoma-derived stroma-inducing clone, P29, highly expresses a syndecan-like proteoglycan exhibiting specific binding to fibronectin, a major constituent of the interstitial matrix formed by the induced stromal cells, via its heparan sulphate chains [Itano, Oguri, Nakanishi and Okayama (1993) J. Biochem. (Tokyo) 114, 862-873]. On metabolic labelling of the proteoglycan with [32P]Pi, followed by identification of the radiolabelled material using glycanases, almost all the isotope was found to have been incorporated into a core portion of molecular mass 48 kDa, which was generated by digestion with heparan sulphate lyase I plus chondroitin ABC lyase. Immunoblotting of the core protein with a monoclonal antibody, F58-6G12, demonstrated that the proteoglycan was mouse syndecan-2. CsCl-density-gradient centrifugation after mild treatment of liposome-intercalated 32P-labelled syndecan-2 with trypsin resulted in clear separation of the radioactivity into a bottom fraction containing all the glycosaminoglycans (accounting for 40% of the total radioactivity) and a top fraction containing liposome-associated peptides (60%). The former isotope was shown to be linked covalently to both heparan sulphate and chondroitin sulphate chains, probably at their bridge regions. The latter was mostly attributed to phosphoserine, the one and only phosphorylated amino acid released on acid hydrolysis of this proteoglycan, strongly suggesting that the phosphorylation occurs at a specific serine residue(s) in the cytoplasmic domain of the core protein.

Localization of histamine N-methyltransferase messenger RNA in human nasal mucosa

BACKGROUND

Histamine is metabolized mainly by histamine N-methyltransferase (HMT) to N tau-methylhistamine in human nasal mucosa. Human HMT cDNA has been cloned and expressed in COS cells. The purpose of this study was to determine the localization of HMT METHODS: The fragment (nucleotide residues 430-1055) of human HMT cDNA was subcloned in a Bluescript vector (Stratagene, La Jolla, Calif.), and HMT sense anti-sense RNA probes were made with T7 and T3 RNA polymerases. In situ hybridization with digoxigenin-labeled RNA probes was performed on surgical specimens of human nasal turbinates.

RESULTS

HMT mRNA was localized in cells in the epithelium and submucosa, and densely in endothelial cells of vessels. No HMT mRNA was identified in the submucosal glands. The presence of HMT mRNA was confirmed by Northern blot analysis, and HMT activities were also detected in nasal mucosa.

CONCLUSION

Our study indicates that endothelium expresses HMT mRNA, whereas cells in the epithelium and submucosa, which remain unidentified, are an additional source of HMT mRNA.

Temporal frequency deficit in patients with senile dementia of the Alzheimer type: a visual evoked potential study

To study the temporal aspect of visual processing of senile dementia of the Alzheimer type (SDAT), we recorded the steady-state visual evoked potentials (VEPs) to LED goggle stimulation at five different temporal frequencies in 14 patients with SDAT and 14 control subjects. For comparison, we also studied 14 patients with vascular dementia (VD). All subjects were women, and their ages were closely matched. Temporal frequencies were 5, 10, 15, 20, and 30 Hz. The steady-state VEPs were Fourier analyzed, and both the amplitude and phase of the first and second harmonic responses were obtained. There was a significant difference in the amplitude across the three groups for stimulation at 15, 20, and 30 Hz, but no difference at a stimulation of 5 and 10 Hz. Multiple comparison tests revealed that patients with SDAT had a significantly smaller amplitude than normal controls. Patients with VD had lower amplitudes than normal subjects, but this was not statistically significant. In the phase data, there were also no statistically significant differences across the three groups for any of the temporal frequencies. These results indicate that a temporal frequency deficit exists in SDAT. This phenomenon may be explained by the pathology that affects the early stage of visual signal processing.

Differential fibrotic stromal responses of host tissue to low- and high-metastatic cloned Lewis lung carcinoma cells

BACKGROUND

The relationship between host stromal responses and tumor invasion and metastasis is poorly understood. To gain new insights into this relationship, we compared the stromal response in tumor tissues formed by low- and high-metastatic murine lung carcinoma cell lines.

EXPERIMENTAL DESIGN

Mouse Lewis-lung-carcinoma-derived cloned cell lines with different metastatic potentials (P29, LM12-3, and LM60-D6 cells with low-, medium-, and high-metastatic potentials, respectively) were subcutaneously injected, and the resultant tumor tissue was analyzed immunohistochemically for the localization of type I collagen, fibronectin, and tenascin, and biochemically for the levels of glycosaminoglycans. The activities of conditioned media of cultured tumor cells to stimulate DNA synthesis in BALB/c 3T3 cells in vitro were also examined.

RESULTS

In the subcutaneous low-metastatic P29 tumor, fibrillar extracellular matrices and fibroblast-like cells surrounding tumor cells were stained strongly for type I collagen, fibronectin, and tenascin, but only weakly stained in the more highly metastatic LM12-3 and LM60-D6 tumors. Implantation of these cell lines into cerebrum, which does not normally contain interstitial stroma, gave same results. Morphometric analysis of the subcutaneous tumor tissues revealed significantly more fibroblast-like cells and mast cells in the P29 tumor than in the more highly metastatic tumors. Quantitative analysis of glycosaminoglycans present in tumor tissues showed that the hyaluronic acid content of the P29 tumor was more than 5 times that in the more highly metastatic tumors. Furthermore, serum-free conditioned medium prepared from the culture of P29 cells exhibited about 10 times higher mitogenic activity toward BALB/c 3T3 cells than the conditioned medium from the more highly metastatic cells.

CONCLUSIONS

We found an inverse relationship between the host stromal response and spontaneous lung metastasis. The stromal response in the P29 tumor may be induced directly by tumor cells and/or indirectly via mast cell activation. This metastasis model should be useful in understanding the role of stromal response in tumor metastasis.

Effect of pilocarpine on propranolol-induced bronchoconstriction in asthma

To investigate whether increased release of acetylcholine may be involved in propranolol-induced bronchoconstriction (PIB), the inhibitory effect of pilocarpine (Pilo), an agonist of M2-muscarinic receptors that in 11 stable asthmatic subjects. The bronchial responsiveness to Pilo was also measured in terms of Dmin, defined as the cumulative dose at the point where respiratory resistance (Rrs) began to increase. In PIB, the maximum increase in Rrs (Rrs max) after stopping inhalation for 1 min was measured. Atropine reversed PIB. After pilocarpine pretreatment at a dose equal to Dmin, Rrs max divided by baseline Rrs decreased significantly from 206.6 +/- 61.1 to 163.0 +/- 42.6% (mean +/- SD) (p = 0.001). The ratio of PIB (Rrs max/baseline Rrs) with Pilo to PIB without Pilo correlated inversely according to the pretreatment dose (Dmin) of Pilo (p < 0.05). These results suggest increased release of acetylcholine in PIB and that M2-muscarinic receptors are at least in part functioning in stable asthmatic airways.

Membrane-intercalated proteoglycan of a stroma-inducing clone from Lewis lung carcinoma binds to fibronectin via its heparan sulfate chains

A Lewis lung carcinoma-derived low metastatic clone, P29, with a capacity to induce a fibrotic stromal response of host tissue, exhibits tumorigenesis depending on an interstitial matrix formed by the induced stromal cells. Using this clone, in the present study we isolated and characterized a membrane-intercalated proteoglycan that mediates interaction between the tumor cells and interstitial matrix. The tumor cells were cultured in the presence of [3H]glucosamine and [35S]sulfate or [35S]methionine, and hydrophobic proteoglycans were isolated by chromatography on DEAE-Sephacel and then Octyl-Sepharose CL-4B. Proteoglycans with high affinity to the octylresidue were obtained from the cell layer but not to any significant extent from the medium. By CsCl density gradient centrifugation, they were separated into bottom, middle, and top subfractions, which were shown to consist of homogeneous species with estimated M(r) values of 270,000 (named CPGIIIB), 200,000 (CPGIIIM), and 195,000 (CPGIIIT), respectively, by gel filtration on Sepharose CL-4B. These proteoglycans were intercalated into phosphatidylcholine liposomes, suggesting that they are all membrane-intercalated proteoglycans. Analyses of their glycosaminoglycans with chondroitinase ABC and heparitinase I plus II demonstrated that they all contain heparan sulfate as a major glycosaminoglycan (58-85%) and chondroitin 4-sulfate as a minor one (15-42%). Of these three proteoglycans, only CPGIIIB proteoglycan bound specifically to fibronectin-Sepharose 4B under physiological conditions. Molecular analyses of this proteoglycan by Sepharose CL-4B or SDS-PAGE before and after treatments with glycosaminoglycan degradation enzymes or trifluoromethanesulfonic acid demonstrated that CPGIIIB proteoglycan is a hybrid proteoglycan having heparan sulfate and chondroitin 4-sulfate chains on the same core protein with an M(r) of 40,000. Affinity chromatographies of the CPGIIIB proteoglycan on fibronectin-Sepharose 4B after treatments with these enzymes demonstrated that it bound to fibronectin via its heparan sulfate chains. On the basis of the above results, we propose that the CPGIIIB proteoglycan mediates the interaction between the tumor cells and interstitial matrix.

Acyclovir-resistant herpes zoster encephalitis successfully treated with vidarabine: a case report

A 78-year-old man developed herpes zoster virus (HZV) encephalitis. Initially, treatment with aciclovir (750 mg per day) improved CSF cell count and protein level. During the treatment, however, encephalitis in the patient deteriorated in spite of the treatment with aciclovir, suggesting that HZV in the patient had become resistant to aciclovir. Subsequent treatment with vidarabine (600 mg per day, for 15 days) resulted in dramatic improvement in CSF pleocytosis. About two months after the discontinuation of vidarabine, the CSF cell count was normal. The patient became alert gradually, but his amnestic syndrome remained unchanged. Vidarabine may be recommended in the treatment of HZV encephalitis when aciclovir is not effective.

Decrease in beta-adrenergic receptors of lymphocytes in spontaneously occurring acute asthma

To clarify changes in beta-adrenergic receptor (BAR) density in spontaneously occurring acute asthma, BAR binding studies were performed on peripheral blood lymphocytes in eight asthmatic and ten normal subjects. Spirometry also was performed. Maximum binding capacity (Bmax) of BAR in acute asthma was significantly lower by 44.2 percent compared with that in stable asthma; FEV1/FVC ratio decreased by 23.9 percent. The Bmax for acute asthma also was significantly lower than that in normal subjects. The Bmax of BAR in all subjects was significantly correlated with FEV1/FVC ratio and percent FEV1. The percentage decrease in the FEV1/FVC ratio and FEV1 from the stable to acute state for each asthmatic subject did not correlate with corresponding percentage decrease in Bmax. These data demonstrate that BAR density of lymphocytes decreases substantially in acute asthma and, simultaneously, suggest that some factors other than the BAR mechanism contribute to the airway obstruction during acute asthma.

Difference in laminin expression between high and low metastatic cell clones derived from murine Lewis lung carcinoma

We investigated the expression of laminin in two cell lines with different metastatic potentials established from murine Lewis lung carcinoma. Immunostaining of the cells with anti-laminin antibody and Northern blot analysis of laminin mRNA demonstrated that the high metastatic clone expressed less laminin than the low metastatic one. In contrast, expressions of 67 kDa-laminin receptor were at similar levels between these two lines. These findings show the possibility that endogenous laminin may contribute to the difference in metastatic properties in the murine Lewis lung carcinoma cell lines examined.

Muscarinic receptor subtypes in human nasal mucosa: characterization, autoradiographic localization, and function in vitro

Muscarinic receptors play important roles in the regulation of glandular secretion and vasomotor tone in human nasal mucosa. M1, M2, and M3 muscarinic receptor subtypes were pharmacologically characterized in human inferior turbinates by receptor-binding assays using [3H](-)quinuclidinyl benzilate (QNB, identifies total muscarinic receptors) and [3H]-pirenzepine (PZ). Receptors were localized by autoradiography, and their function examined in vitro by assaying mucus secretion from cultured nasal mucosal explants. In competition assays, PZ was employed as a selective muscarinic antagonist for M1 receptors, gallamine and AF-DX 116 for M2 receptors, and 4-DAMP for M3 receptors. These ligands are selective at low nanomolar concentrations, but can interact with other muscarinic receptors at higher concentrations. It is not known if they can interact with putative M4 and M5 muscarinic receptor subtypes. Using [3H](-)QNB, total muscarinic receptor binding was 688.4 +/- 49.6 fmol/mg protein (Bmax), with a Kd of 1.47 +/- 0.13 nM. [3H]-PZ bound to 45% of the total QNB binding sites. In competition experiments, 4-DAMP displaced [3H](-)QNB with the lowest IC50, followed by PZ and AF-DX 116. Autoradiograms demonstrated that [3H](-)QNB binding was completely displaced by 4-DAMP, partially displaced by PZ, but not displaced by gallamine or AF-DX 116, and suggested that M1 and M3 subtypes coexist in submucosal glands. The localization of M1 receptors on submucosal glands was confirmed by direct labeling with [3H]-PZ. [3H]-PZ also labeled vessels, but with a low silver grain density. Autoradiographic [3H]-QNB binding was displaced by 4-DAMP and atropine, but not by PZ, gallamine, or AF-DX 116. In studies of mucus secretion in vitro, 4-DAMP significantly inhibited methacholine-induced secretion. Although less effective, PZ also had significant inhibitory effects. Neither gallamine nor AF-DX 116 had any inhibitory effect. M1 receptors (PZ binding sites) may regulate glandular secretion while M3 receptors (4-DAMP binding sites) may regulate glandular secretion and vasomotor tone in human nasal mucosa.

Difference in blood flow volume of the common carotid artery between vascular and non-vascular dementia detected by colour duplex sonography

Using colour duplex sonography, blood flow volume in the common carotid artery was measured in 72 demented patients and 28 normal controls. Thirty-five patients with a Hachinski's ischaemic score of 7 or above and marked ischaemic lesions on CT were assigned to the vascular dementia (VD) group. Thirty-three patients with probable Alzheimer's disease according to the NINCDS-ADRDA criteria, 2 patients with Parkinson's disease, 1 patient with spinocerebellar degeneration, and 1 patient with Pick's disease were assigned to the non-vascular dementia (nonVD) group. The sum of blood flow volume in the bilateral common carotid arteries (CCA flow) in the nonVD group and in the VD group was lower than that in the control group. The CCA flow in the VD group was lower than that in the nonVD group. Comparison of patients matched for both age and the Hasegawa's dementia rating scale also revealed lower CCA flow in the VD group than in the nonVD group. Linear discriminant function analysis showed that nearly 90% of the demented patients were correctly diagnosed as having VD or as having nonVD. These results show the usefulness of colour duplex sonography in the differential diagnosis of patients with dementia.

Structural differences between heparan sulphates of proteoglycan involved in the formation of basement membranes in vivo by Lewis-lung-carcinoma-derived cloned cells with different metastatic potentials

This study addresses the characterization of heparan sulphates of the basement-membrane proteoglycans in tumour formed after the subcutaneous implantation of Lewis-lung-carcinoma-derived different metastatic clones (P29, LM12-3 and LM60-D6 clones with low, medium and high metastatic potentials respectively). Heparan sulphate proteoglycans (125-158 micrograms of hexuronate/g dry weight of tissue) were isolated from chondroitin ABC lyase digests of a proteoglycan fraction obtained after DEAE-Sephacel chromatography of tissue extracts. The proteoglycans were separated into three molecular species by Sepharose CL-4B chromatography followed by CsCl-density-gradient centrifugation: large proteoglycans with an estimated M(r) of 820,000-130,000, which consisted of two components with low (< 1.34 g/ml; PGII-M) and high (> 1.37 g/ml; PGII-B) density, and a small proteoglycan with an M(r) of less than 80,000 (PGIII). Of these, only the PGII-M proteoglycan (34-37 micrograms of hexuronate/g dry weight) reacted with the antiserum against proteoglycan of Engelbreth-Holm-Swarm-tumour basement membrane, and represented, therefore, a basement-membrane proteoglycan. Digestion with heparan sulphate lyases I and II of the heparan sulphates (M(r) 36,000) from the PGII-M proteoglycan of the three tumours resulted in almost complete depolymerization to give six unsaturated disaccharides identified as 2-acetamido-2-deoxy-4-O-(4-deoxy-alpha-L-threo-hex-4-enopyranosyluron ic acid)-D-glucose, 2-acetamido-2-deoxy-4-O-(4-deoxy-alpha-L-threo-hex-4-enopyranosyluron ic acid)-6-O-sulpho-D-glucose, 2-deoxy-2-sulphamino-4-O-(4-deoxy-alpha-L-threo-hex-4-enopyrano syluronic acid)-D-glucose, 2-deoxy-2-sulphamino-4-O-(4-deoxy-alpha-L-threo-hex-4-enopyrano syluronic acid)-6-O-sulpho-D-glucose, 2-deoxy-2-sulphamino-4-O-(4-deoxy-2-O-sulpho-alpha-L-threo-hex-4- enopyranosyluronic acid)-D-glucose and 2-deoxy-2-sulphamino-4-O-(4-deoxy-2-O-sulpho-alpha-L-threo-hex-4- enopyranosyluronic acid)-6-O-sulpho-D-glucose. Comparison of the relative amounts of these disaccharides produced from the three tumour-derived heparan sulphates demonstrated that the degree of sulphation of the heparan sulphates correlated with the degree of morphological organization of the tumour basement membranes; the heparan sulphate from the more highly metastatic tumour with more highly organized basement membrane exhibited a higher degree of overall sulphation along the glycosaminoglycan chains, which was due to an increased content of the three repeating disaccharides having 6-O-sulphated glucosamine residues.

Characterization and autoradiographic localization of histamine H1 receptors in human nasal turbinates

To examine the localization of histamine H1 receptors (H1R) in human nasal mucosa, the autoradiographic distribution of H1R was studied in human nasal inferior turbinates. Cryostat sections were incubated with various concentration of [3H]pyrilamine in saturation-binding studies and with 1 nmol/L of [3H]pyrilamine for autoradiography. Nonspecific binding was determined by adding 2 mumol/L of pyrilamine. Scatchard analysis demonstrated high-affinity binding sites with a maximum binding capacity of H1R of 193 +/- 46 fmol/mg of protein, and dissociation constant was 0.6 +/- 0.1 nmol/L. Autoradiograms indicated H1R exist exclusively on the endothelium of vessels. No specific labeling could be observed in the submucosal glands or epithelium. These results extend and support our previous finding that histamine directly causes vascular permeability through H1R and stimulates nasal glandular secretion indirectly through reflexes.

Morphological characteristics of tumours formed by Lewis lung carcinoma-derived cloned cell lines with different metastatic potentials: structural differences in their basement membranes formed in vivo

Tumour basement membrane (BM) is an extracellular matrix produced by tumour cells of epithelial origin. We examined the structure and function of the tumour BM of tumour tissues formed by Lewis lung carcinoma-derived cloned cell lines (P29, LM12-3 and LM60-D6 cells) with low, medium and high metastatic potentials, respectively. Immunohistochemical staining of major BM constituents laminin and type IV collagen demonstrated that all the cell lines produced and deposited these materials extracellularly in vivo. However, the continuity of the tumour BM composed of these materials was much greater in the higher metastatic LM12-3 and LM60-D6 tumours than in those with the low metastatic P29 tumour. Electron microscopic examination revealed that in the higher metastatic tumours, especially the LM60-D6 tumour, the tumour BM had a highly organized structure consisting of lamina densa and lamina rara. Parallel bilayers of BM and their fusion were often observed and tumour cells were in direct contact with the BM. In the vicinity of tumour blood vessels, similar interactions between the tumour BM and the vascular BM were observed, and the tumour cells rested on their own BM, the fused BM or the vascular BM. In contrast, in the low metastatic tumour in which the tumour BM was not clearly defined, this close contact between tumour cells and the vascular BM was not observed. In vitro studies showed that the higher metastatic cells adhered more firmly than the LMP cells to a subendothelial matrix. These results suggest that the adhesiveness of tumour cells to the vascular BM in vivo is correlated with their ability to form an integrated BM in vivo, and that this adhesiveness of the tumour cells may be mediated in part by the tumour BM via BM fusion.

Close association between tumour cells and vascular basement membrane in gastric cancers with liver metastasis. An immunohistochemical and electron microscopic study with special attention to extracellular matrices

To investigate morphological features valuable in estimating the propensity of gastric cancer to metastasize to the liver, we examined the primary tumours from 49 surgically resected advanced gastric cancers (24 with liver metastasis) and 45 autopsy cases, 19 with liver metastasis. We paid special attention to extracellular matrices--connective tissue stroma and basement membrane (BM)--using immunohistochemistry and electron microscopy. Type IV collagen staining showed that in differentiated carcinomas neoplastic glands were occasionally located in close proximity to the BM of thin-walled tumour blood vessels in back-to-back fashion. In poorly differentiated lesions, tumour cells were also oriented toward the vascular BM in pseudorosette-like pattern. Type III collagen staining and electron microscopy showed that in such regions tumour cells, with continuous or discontinuous BM, were immediately adjacent to vascular BM with no connective tissue stroma in between. On occasion tumour cells were in direct contact with vascular BM. These close associations were often found in carcinomas with a medullary growth pattern, irrespective of the degree of histological differentiation. However, they were virtually never seen in their benign counterpart. Of the resected cases, all 24 with liver metastasis showed this association, whereas only 10 of 25 (40%) without liver metastasis did so (P less than 0.001). In the autopsied cases, a similar positive correlation was observed between liver metastasis and this association. Furthermore, the tumor cells showing this juxtaposition showed evidence of vascular invasion. These results suggest that the close association between tumour cells and vascular BM is specific to the malignant neoplasm, and may be related to liver metastasis. Immunohistochemistry can be a great help in estimating the probability of liver metastasis.

Substance P and neurokinin A in human nasal mucosa

The tachykinins substance P (SP) and neurokinin A (NKA) were studied in human inferior turbinate nasal mucosa by radioimmunoassay, immunohistochemistry, and autoradiography and for their effect upon mucus release in an in vitro culture system in order to infer their potential functions in the upper respiratory tract. Similar amounts of SP (1.03 +/- 0.12 pmol/g wet weight; mean +/- SEM; n = 26) and NKA (0.76 +/- 0.23; n = 7) were found. NKA and SP immunoreactive nerve fibers were found in the walls of arterioles, venules, and sinusoids and as individual fibers in gland acini, near the basement membrane, and in the epithelium. [125I]SP bound to arterioles, venules, and glands. [125I]NKA bound only to arterioles. In short-term explant culture of fragments of human nasal mucosa, both 1 microM SP and 1 microM NKA stimulated release of [3H]glucosamine-labeled respiratory glycoconjugates. These results indicate that SP and NKA have similar distributions in nociceptive sensory nerves in human nasal mucosa. The distribution of [125I]SP binding sites is consistent with a role for SP as a vasodilator and mucous secretagogue. The presence of [125I] NKA binding sites on vessels suggests a primary role for NKA in regulating vasomotor tone.

Purification and characterization of novel heparan sulfate proteoglycans produced by murine erythroleukemia cells in the growing phase

Murine erythroleukemia cells (Friend erythroleukemia cells of a C-10-6 line) synthesized sulfated glycosaminoglycans consisting mainly of heparan sulfate (more than 95%) with a small amount of chondroitin 4-sulfate. The heparan sulfate occurred as proteoglycans, of which the cell-associated component was separated into urea-insoluble (UI) and urea-soluble (US) fractions. The UI proteoglycan consisted of a single homogeneous molecular species with an estimated Mr of 360,000 (C(UI)PG), whereas the US component was composed of two subfractions: a homogeneous species with an Mr of 280,000 (C(US)PGI) and a mixture of compounds with Mr values of less than 80,000 (C(US)PGII), which were isolated in yields of about 110, 340, and 80 micrograms of hexuronate (HexUA), respectively, from 1.37 g of an acetone powder prepared from 5.7 x 10(9) cells in the logarithmic phase of growth. The proteoglycan released into the medium (12 liters) was a single homogeneous species with an Mr of 320,000 (MPG) which was purified in a yield of 500 micrograms of hexuronate. The major, cell-associated proteoglycan, C(US)PGI, had very high contents of serine and glycine, accounting for approximately 80% of the total amino acids. This proteoglycan as well as the other two large proteoglycans, C(UI)PG and MPG, were highly resistant to degradation by various proteinases. These three proteoglycans, C(UI)PG, C(US)PGI, and MPG, had heparan sulfates with estimated Mr values of 32,000, 27,000, and 30,000. On the other hand, the Mr of the smaller proteoglycan, C(UI)PGII, was not significantly different before and after beta-elimination, indicating that it contains only a small peptide, if any. The heparan sulfate of this proteoglycan consisted of smaller and heterogeneous molecular species with Mr values of 26,000, 20,000, and 4,000. Digestion of these heparan sulfates with heparitinase I plus II resulted in almost complete depolymerization and gave six unsaturated disaccharides, delta HexUA-GlcNAc, delta HexUA-Glc-NAc(6-SO4), delta HexUA-GlcNSO3, delta HexUA-GlcNSO3 (6-SO4), delta HexUA(2-SO4)-GlcNSO3, and delta HexUA(2-SO4)-GlcNSO3(6-SO4). The relative amounts of these disaccharides generated from the individual heparan sulfates showed that an average ratio of sulfate residues to repeating disaccharide units of the C(US)PGII-derived heparan sulfate (0.97) was significantly higher than those of the other three large proteoglycan-derived glycosaminoglycans (0.54-0.70).