Contrasting effects of an aminobisphosphonate, a potent inhibitor of bone resorption, on lipopolysaccharide-induced production of interleukin-1 and tumour necrosis factor alpha in mice

1. Aminobisphosphonates (aminoBPs), potent inhibitors of bone resorption, have been reported to induce inflammatory reactions such as fever and an increase in acute phase proteins in human patients, and to induce the histamine-forming enzyme, histidine decarboxylase, in mice. In the present study, we examined the effect of aminoBP, 4-amino-1-hydroxybutylidene-1,1-bisphosphonic acid (AHBuBP), on the production of the pro-inflammatory cytokines, IL-1 and TNFalpha, in mice. 2. Intraperitoneal injection of AHBuBP did not itself produce detectable levels of IL-1 (alpha and beta) and TNFalpha in the serum. However, the elevation of serum IL-1 induced by lipopolysaccharide (LPS) was greatly augmented in mice injected with AHBuBP 3 days before the LPS injection, whereas the LPS-induced elevation of serum TNFalpha was almost completely abolished. 3. Spleen and bone marrow cells taken from mice injected with AHBuBP produced IL-1beta in vitro spontaneously, and the production was augmented following the addition of LPS. Cells that accumulated in the peritoneal cavity in response to AHBuBP produced a particularly large amount of IL-1beta. However, AHBuBP treatment of mice did not lead to an impairment of the in vitro production of TNFalpha by these three types of cells. 4. Liposomes encapsulating dichloromethylene bisphosphonate (a non-amino BP) selectively deplete phagocytic macrophages. When an intraperitoneal injection of these liposomes was given 2 days after an injection of AHBuBP, there was a marked decrease in the LPS-induced elevation of serum IL-1 (alpha and beta) (LPS being injected 3 days after the injection of AHBuBP). 5. These results indicate that AHBuBP has contrasting effects on the in vivo LPS-induced production of IL-1 and TNFalpha in mice, enhancing the production of IL-1 by phagocytic macrophages and suppressing the production of TNFalpha, although underling mechanisms remain to be clarified.

Microsatellite instability and somatic mutations in endometrial carcinomas

Recently, microsatellite instability (MI) has been demonstrated in some types of human cancers. In this study, we attempted to determine the frequency of MI in endometrial cancers and evaluate whether replication error (RER)-positive phenotype is correlated with known genetic mutations or the aberrations of other pathways in endometrial cancers. Seventy-two primary endometrial cancers were examined for microsatellite instability. Eleven tumors (15%) had RERs at two or more microsatellite loci, suggesting that generalized MI may be a molecular manifestation of endometrial cancers. We next examined whether the MI was associated with changes in the K-ras protooncogene, p53 tumor suppressor gene, and 18q LOH, which were frequently detected in endometrial cancers. The MI did not confer the potential to produce point mutations in the K-ras gene or 18q LOH, whereas the data were insufficient to identify the correlation between MI and p53 mutations in the cancers. These results suggest the presence of multiple mutation subsets that act in a complementary fashion in endometrial cancer development.

Dual regulatory effects of interferon-alpha, -beta, and -gamma on interleukin-8 gene expression by human gingival fibroblasts in culture upon stimulation with lipopolysaccharide from Prevotella intermedia, interleukin-1alpha, or tumor necrosis factor-alpha

In a previous study, we demonstrated that the amount of interleukin (IL)-8 mRNA expressed by human gingival fibroblasts stimulated with lipopolysaccharide (LPS) from Prevotella intermedia ATCC 25611 is increased by pre-treatment with beta or gamma interferon (IFN-beta or -gamma). In the present study, we identified the regulatory effects of these IFNs on IL-8 mRNA expression and IL-8 production by human gingival fibroblasts. Priming with IFN-alpha (alpha), -beta, or -gamma upregulated the IL-8 mRNA expression in response to P. intermedia LPS, whereas co-stimulation with these IFNs reduced the amount of mRNA expressed by the cells. The regulation of IL-8 mRNA expression induced by recombinant human tumor necrosis factor-alpha (rHuTNF-alpha) or rHuIL-1alpha was similar to that induced by LPS. The IL-8 mRNA expression in response to P. intermedia LPS was enhanced by IFN-gamma independently of de novo protein synthesis, and was regulated, at least in part, at the transcriptional level. The IL-8 mRNA accumulation in response to P. intermedia LPS was inhibited by tosylphenyl-alanyl chloromethyl-ketone, an inhibitor of NF-kappaB activation, although the NF-kappaB activation itself was not altered by IFN-gamma. These findings suggest that IFNs might be capable of both enhancing and inhibiting inflammatory responses in periodontal tissues through the dual regulation of IL-8 production by gingival fibroblasts in response to bacterial components and cytokines.

The accelerated increase in lean body mass of pre-pubescent Japanese boys at 10 to 11 years of age

The present study investigated changes in body composition in relation to growth to evaluate at what age Japanese children begin their pre-pubescent growth spurt. Children aged 9 were followed to age 10 (The age 9 group), and those aged 10 were followed to age 11 (The age 10 group). The increase in lean body mass per one-year increment of body height (Δ LBM/ ΔBH) in the age 10 boys group was significantly higher than that in the age 9 boys group. In both the age 9 and 10 boys groups, the high Body Mass Index (BMI) boys showed greater mean ΔLBM/ ΔBH than that for the normal BMI boys. Our results of accelerated Δ LBM/ ΔBH from age 10 to 11 in Japanese boys hypothesize that an increase in LBM demonstrates pre-pubescent growth.

Heterogeneous expression and release of CD14 by human gingival fibroblasts: characterization and CD14-mediated interleukin-8 secretion in response to lipopolysaccharide

To identify the role in periodontal inflammatory diseases of human gingival fibroblasts (HGF), the major constituents of gingival tissue, the expression of CD14, a possible lipopolysaccharide (LPS) receptor, and the release of soluble CD14 (sCD14) by HGF were examined. Among the HGF samples from the nine donors tested, more than 50% of the HGF from five donors expressed CD14 but less than 20% of HGF from the other four donors did so, as determined by flow cytometric analysis. The CD14 expression on the cell surface was correlated with the expression of CD14 mRNA. The HGF and skin and lung fibroblasts tested expressed no CD18, which indicates that fibroblasts do not possess other LPS receptors, such as CD11b/CD18 and CD11c/CD18. The CD14 expression by the HGF was decreased after subculturing and was highest at the confluent stage of culture. The treatment of high-CD14-expressing (CD14(high)) HGF with phosphatidylinositol-phospholipase C reduced CD14 expression; this result and the increase in a 55-kDa CD14 indicate that the membrane CD14 (mCD14) on the HGF may be a 55-kDa glycosylphosphatidylinositol-anchored protein. CD14(high) HGF spontaneously released 48- and 57-kDa sCD14. The total release of sCD14 by the HGF was augmented by gamma interferon and Escherichia coli LPS in accordance with the increased expression of mCD14. The CD14(high) HGF secreted interleukin-8 in response to LPS, and the secretion was completely inhibited by anti-CD14 antibody. These results suggest that (i) HGF consist of populations that are heterogeneous on the basis of different levels of expression of CD14 and (ii) CD14(high) HGF secrete inflammatory cytokines in response to LPS via CD14.

Clinicopathologic and immunohistochemical analyses in lung metastasis of colorectal carcinoma

We compared the immunohistochemical staining patterns of carcinoembryogenic antigen (CEA), CA19-9 and proliferating cell nuclear antigen (PCNA) between specimens from 13 patients who had undergone surgery for colorectal carcinoma with lung metastasis (lung metastasis group) and specimens from 13 patients who had no evidence of recurrence or metastasis within at least 5 years after colorectal resection (no metastasis group). The PCNA labeling indices of primary and metastatic lesions were 53.29 8.88% and 63. 26 6.21% (p<0.001), respectively. The PCNA labeling index in the no metastasis group was 26 12.9% (p<0.001). There was no significant difference in the CA19-9 staining patterns between the two groups. The CEA distribution patterns in the primary and lung metastatic lesions were different even in the same case. The original tumor cells showed apical or C1 localization, whereas metastatic cells showed C2 localization. These findings indicate that patients having colorectal carcinoma with a high PCNA labeling index have a high probability of lung metastasis, and that the CEA distribution pattern would change after original tumor resection.

Interferon-alpha therapy for chronic active Epstein-Barr virus infection: potential effect on the development of T-lymphoproliferative disease

PURPOSE

A patient with aggressive chronic active Epstein-Barr virus (CAEBV) infection is described whose disease activity subsided after interferon (IFN)-alpha therapy.

PATIENT AND METHODS

The patient had intermittent fever, cytopenia, liver dysfunction, hepatosplenomegaly, abnormal titers of EBV-associated antibodies, and positive EBV genomes.

RESULTS

Despite repeated trials of the antiviral agents prednisolone and gamma-globulin, his condition deteriorated. The administration of IFN-alpha (1 x 10(5) U/kg subcutaneously 3 times per week) led to a dramatic clinical improvement. During the IFN-alpha therapy, the rearrangement bands of T-cell antigen receptor genes disappeared assessed by Southern blotting with a decrease in the number of activated T cells, although the EBV-genome remained evident.

CONCLUSIONS

These observations suggest that IFN-alpha is useful in managing CAEBV, possibly restraining the clonal development of T-lymphoproliferative disease (LPD) and EBV-associated B-LPD, although it does not eradicate the proliferation of EBV.

Nonsense mutation in exon 4 of human complement C9 gene is the major cause of Japanese complement C9 deficiency

Deficiency of the ninth component of human complement (C9) is the most common complement deficiency in Japan but is rare in other countries. We studied the molecular basis of C9 deficiency in four Japanese C9-deficient patients who had suffered from meningococcal meningitis. Direct sequencing of amplified C9 cDNA and DNA revealed a nonsense substitution (CGA-->TGA) at codon 95 in exon 4 in the four C9-deficient individuals. An allele-specific polymerase chain reaction system designed to detect exclusively only one of the normal and mutant alleles indicated that all the four patients were homozygous for the mutation in exon 4 and that the parents of patient 2 were heterozygous. The common mutation at codon 95 in exon 4 might be responsible for most Japanese C9 deficiency.

Operational performance of the NIJI-III superconducting storage ring

The operational performance of the NIJI-III superconducting storage ring has been studied with particular attention focused on the vacuum performance of the cold-bore chamber. Photon-stimulated gas desorption in the cold-bore chamber was examined after commissioning the storage ring. It was confirmed that the photon-stimulated gas desorption due to diffuse reflection of synchrotron radiation at the absorber was not dominant in the gas desorption when the electron beam was accumulated in the storage ring.

Dietary effects of fatty acids on growth and metastasis of KPL-1 human breast cancer cells in vivo and in vitro

To evaluate the effects of dietary fats on breast cancer growth and metastasis, KPL-1 human breast carcinoma cells which have a propensity for axillary lymph node metastasis when inoculated into the thoracic mammary fat pad of female nude mice were examined. The mice were fed one of three semipurified diets containing 9.5% eicosapentaenoic acid plus 0.5% linoleic acid (EPA diet), 10% linoleic acid (LA diet), or 9.5% palmitic acid plus 0.5% linoleic acid (PA diet), or commercial laboratory chow containing 8.5% fat of which 4.1% was LA, 1.1% was PA, 0.06% was EPA, and 3.24% was other (Standard diet) starting 19 days before tumor cell inoculation and continuing until the end of the experiment (43 days after tumor cell inoculation). The tumor growth was faster and at a higher incidence in the mice fed the LA diet, and much slower and at a lower incidence in the EPA diet group compared with the mice fed the PA or Standard diet; the two separate experiment demonstrated identical results. The differences in tumor weight between the LA and PA groups and between the PA and EPA groups were significant (P < 0.05, respectively) at the termination of the experiment; the differences were due to different tumor cell proliferation rates. In an in vitro MTT assay, fatty acids showed direct stimulatory or inhibitory effects on the KPL-1 cells. Lymph node metastasis was seen in the LA and Standard diet groups, whereas it was not seen in the PA or EPA groups. The body weights were significantly lighter in the LA and EPA groups compared with the PA and Standard diet groups (P < 0.05, respectively). The results indicate that the EPA diet produced a reduction in tumor cell growth and metastasis whereas the LA diet had an enhancing effect on these parameters; dietary fatty acids may thus have a direct role in the growth and metastasis of human breast carcinoma independent of their systemic effects.

Eating habits, activity, lipids and body mass index in Japanese children: the Shiratori Children Study

OBJECTIVE

To describe the eating habits and physical activity of Japanese children aged 10 y, and to investigate their relationship to lipids and body mass index (BMI); also to study the relationship between BMI and lipids in these children.

DESIGN

This was a cross-sectional study conducted at six schools in Shiratori, Japan during 1992-1994. Physical examinations and questionnaires were used to collect data from 457 fifth grade children, aged 10 y.

RESULTS

The diet of these children was mixed, with Japanese and Western foods almost equally reported. Boys were more active than girls. More active children had higher high density lipoprotein cholesterol (HDL-C), and children who ate a more Japanese diet had slightly lower HDL-C. BMI was positively related to cholesterol, low density lipoprotein cholesterol (LDL-C), triglycerides and inversely related to HDL-C. The amount of rice intake was positively associated with the BMI of these children.

CONCLUSION

In our study of Japanese children aged 10 y, their diets were fairly Westernized, and most children were fairly inactive based on our activity score. Although obesity is low in these young Japanese subjects (14.1%), children who were obese (BMI>20) had worse lipid profiles than those who were not obese. An exceptionally high rice intake was associated with obesity, and thus may be an early warning sign for future obesity.

Finger skin temperature and laser-Doppler finger blood flow in subjects exposed to hand-arm vibration

OBJECTIVES

This study was aimed to assess the peripheral circulatory functions of forestry workers exposed to hand-arm vibration, using simultaneous measurements of finger skin temperature (FST) and finger blood flow (FBF).

METHODS

The subjects were five men with vibration-induced white finger (VWF), four subjects with numbness in their hands and five exposed controls without any signs or symptoms related to vibration syndrome. Simultaneous measurements of FST and laser-Doppler FBF were performed before, during and following a 10-min recovery period after the hand was immersed in cold water (10 degrees C, 10 min). Partitional measurements of finger blood flows could be made between the capillaries and deeply located vessels using two laser-Doppler flow probes having narrower and wider optic fiber separations.

RESULTS

The FST as well as the FBF of the capillary and deeply located vessels during and following the cold immersion test in those with VWF and in the subjects with numbness had a slight increase immediately following the cold immersion and no tendency to be augmented as the time span increased. After the cold immersion test, the control group had significantly greater FST and FBF compared to other groups. Particularly, from the 5th to the 10th min after the cold provocation, the values of FBF of the deeply located vessels in those with VWF were significantly lower than the controls. During the course of observation, the FST had significantly linear relationship with the recorded capillary and deep FBF values, and that was much closely correlated with the deep FBF (i.e., P < 0.01 in each selected condition). The slope of the regression lines in the capillary were steeper and shallow in the deep FBF.

CONCLUSIONS

In addition to the measurement of capillary FBF, more detailed and accurate information on the peripheral circulatory functions of vibration-exposed subjects can be obtained by including the assessment of the deep FBF.

Involvement of NK1+ T cells and their IFN-gamma production in the generalized Shwartzman reaction

IL-12 (or LPS) priming and subsequent challenge by LPS produces the generalized Shwartzman reaction. IFN-gamma induced by IL-12 is a crucial cytokine in the priming phase. In vivo depletion of both NK cells and NK1+ alphabeta T cells of mice by anti-NK1.1 Ab greatly reduced the elevation of serum IFN-gamma induced by IL-12 and significantly reduced mortality after subsequent injection of LPS, whereas depletion of NK cells alone by anti-asialo GM1 Ab only partially decreased serum IFN-gamma, and lethality was not changed. Cell sorting and culture experiments confirmed that liver NK1+ alphabeta T cells of IL-12-injected mice produced greater amounts of IFN-gamma than did liver NK cells. MHC class I-deficient mice of C57BL/6 background, which lack a majority of NK1+ alphabeta T cells, produced low amounts of IFN-gamma by IL-12; no mortality was observed after the LPS challenge. However, production of TNF-alpha in the second phase (after LPS challenge) was not inhibited by depletion of NK cells alone or both subsets. IL-12 and subsequent LPS challenge activated NK1+ alphabeta T cells in the liver and induced strong cytotoxicity of these cells not only against tumor cells (including Fas-negative tumors) but also against a syngeneic hepatocyte cell line. Our findings show that IFN-gamma produced by NK1+ alphabeta T cells is essential for the IL-12 priming of the Shwartzman reaction, and the autoreactivity of NK1+ alphabeta T cells in the liver is involved in the hepatic disorders that are sometimes caused by IL-12, LPS, or the generalized Shwartzman reaction.

Mycoplasma pneumoniae meningoencephalitis and cerebellitis with antiganglioside antibodies

A male patient with acute meningoencephalitis and cerebellitis associated with Mycoplasma pneumoniae infection is described. T2-weighted MRI demonstrated a high-intensity lesion involving the deep white matter of the right cerebellar hemisphere, which was not enhanced on injection of gadolinium. Brain perfusion scintigraphy revealed hypoperfusion in the bilateral cerebellar hemisphere. Polymerase chain reaction analysis using M. pneumoniae-specific primers failed to reveal the existence of the M. pneumoniae genome in cerebrospinal fluid. Conversely, serum antibodies to gangliosides (GM1, GM2, and GT1b) were detected, suggesting a mycoplasma-related neurologic disorder mediated by an immunologic mechanism. These findings support the hypothesis that vasculopathy and demyelination caused by an immunologic mechanism play an important role in the pathogeneses of neurologic disorders associated with M. pneumoniae infection.

Response of parathyroid hormone to anaerobic exercise in adolescent female athletes

It has been shown that moderate exercise suppresses parathyroid hormone (PTH) secretion, while strenuous exercise is apt to induce continuous secretion, which has a negative effect on bone mineral densities (BMD). The present study investigated a typical response of PTH to brief exercise. The study group comprised six adolescent female basketball players whose BMD were within normal limits. Maximal anaerobic power by three-step cycling was loaded on each subject. The first blood sample was drawn 30 min prior to testing test, the second was immediately following, the third was 15 min after, and the fourth was 30 min after. The proportional change in plasma volume was -11.5% immediately following (P < 0.05), +2.1% 15 min after, and +5.5% at 30 min after exercise (P < 0.05). The expected value was calculated on the assumption of no effect, except changes in plasma volume, by exercise. The measured values of PTH and calcium (Ca) immediately after exercise were lower than each of the expected values (P < 0.05 for both). At 15 min after, there was no significant difference between expected and measured values of PTH, Ca and magnesium (Mg), respectively. At 30 min after, the measured value of Ca and Mg was higher than each expected value (P < 0.05 for both). It was concluded that PTH secretion is suppressed transiently immediately after maximal anaerobic exercise and is then stimulated during the recovery time in normal BMD subjects.

[An evaluation of the biting force, the body composition and the amount of masticatory action in young females]

The purposes of this study were to investigate factors related to maximum biting force and to understand the characteristics of physical properties of daily ingested foods in young females. One hundred and forty subjects aged 18-23, with Angle 1 class occlusion, had not suffered from periodontitis, and had not been treated for preparation of tooth crown of first molars. Body height and weight were measured, and percentage of body fat, fat mass (FM) and lean body mass (LBM) were estimated, using the impedance analyzer. The maximum biting force was measured by the press sensation method. According to the formula on the basis of our new version of Yanagisawa's food classification, the mean value of the amount of masticatory action for one day was calculated. Subjects were divided into the normal biting force and the low biting force groups with -1SD of the maximum biting force, in order to compare body composition and backgrounds in sports activities between these two groups. Multiple linear regression analysis was carried out, employing maximum biting force (kg.f) as a dependent variable, and having a background in sports activities, FM, LBM, the number of missing teeth, the number of dental caries and the amount of masticatory action for one day as independent variables. Results were as in the following: 1) The proportion of subjects who had a background in sports activities in the low biting force group were less than that in the normal biting force group (p < 0.01). 2) Having a background in sports activities and LBM were positively correlated to maximum biting force (p < 0.01), while the amount of masticatory action for one day was not. 3) All subjects, especially those in the low biting force group seldom had food requiring the highest amount of masticatory action.

CONCLUSION

Having a background in sports activities and LBM are positively correlated with the maximum biting force, while the amount of masticatory action for one day was not correlated positively nor negatively in young females.

Comparison of bactericidal effects of commonly used antiseptics against pathogens causing nosocomial infections. Part 2

Opportunistic infections caused by gram-negative rods (GNR), conventionally regarded as organisms with low or no pathogenicity, and intractable infections caused by various resistant organisms pose a great problem now. In view of this, we determined the bactericidal effects of 5 commonly used disinfectants using as the test strains Xanthomonas maltophilia and Serratia marcescens, chosen among other GNR since they often cause nosocomial infections. Regarding the bactericidal activities against X. maltophilia and S. marcescens, both sensitive strains and resistant strains were killed within 20 s of exposure to povidone-iodine and sodium hypochlorite. With chlorhexidine, 1 strain each of both species was not killed within 10 min of exposure at a concentration of 0.2%. Both sensitive strains and resistant strains of X. maltophilia were killed within 20 s of exposure to benzalkonium at 0.02%, while a concentration of 0.1% was required for benzalkonium to kill S. marcescens within 20 s. With Tego-51, both sensitive strains and resistant strains of X. maltophilia were killed within 20 s at 0.02%, while 1 strain of S. marcescens was not killed within 20 s at a concentration of 0.1%. In the use of disinfectants, comparative bactericidal effects of various disinfectants against clinical isolates should be taken into consideration.

The influence of long-term treatment with povidone-iodine on thyroid function

Povidone-iodine (PVP-I) is generally very safe, but cases of thyroid dysfunction induced by PVP-I have been reported. The effect of long-term treatment with PVP-I on thyroid function was to be assessed. In 40 inpatients of the department of neurology, the status of the use of PVP-I preparations and their effects on serum inorganic iodine levels and thyroid functions were investigated. In 27 patients treated with PVP-I for a long term, inorganic iodine levels were significantly increased as compared to those in 13 patients without PVP-I treatment. Out of 27 patients treated with PVP-I in the long term, subclinical hypothroidism was seen in 3 patients, mild hyperthroidism was seen in 1 patient, and subclinical hyperthyroidism was suspected in 7 patients. Patients treated with PVP-I for a long time should be observed carefully for any manifestation of thyroid dysfunction.

A novel component different from endotoxin extracted from Prevotella intermedia ATCC 25611 activates lymphoid cells from C3H/HeJ mice and gingival fibroblasts from humans

A novel immunobiologically active fraction was prepared from a phenol-water extract of Prevotella intermedia ATCC 25611 by Sephadex G-100 column chromatography. The fraction consisted mainly of carbohydrate and protein and was devoid of fatty acid. The fraction showed high-molecular-weight bands (10,000 to 12,000) on deoxycholate polyacrylamide gel electrophoresis (DOC-PAGE) and was scarcely active in a Limulus test. We designated the fraction Prevotella glycoprotein (PGP). The PGP fraction showed strong mitogenicity on splenocytes and cytokine-inducing activities on peritoneal macrophages from both C3H/HeJ and C3H/HeN mice, and it stimulated human gingival fibroblasts to produce cytokines. The activities of the PGP fraction were resistant to heat inactivation (100 degrees C for 1 h) and protease treatments and were scarcely inhibited by polymyxin B. In contrast, the purified lipopolysaccharide fraction (LPS-PCP) extracted from the same bacterium with a phenol-chloroform-petroleum ether mixture, which showed strong Limulus activity and a single low-molecular-weight band (approximately 3,000) on DOC-PAGE, lacked the activities on splenocytes and macrophages from C3H/HeJ mice and human gingival fibroblasts. The activities of the LPS-PCP fraction on cells from C3H/HeN mice were completely inhibited by polymyxin B. The LPS extracted from the same bacterium with hot phenol-water (LPS-PW) exhibited the properties of both the PGP fraction and the LPS-PCP fraction. These findings suggest that the unique bioactivities of the LPS-PW fraction of oral black-pigmented bacteria reported to date, which differed from those of the classical endotoxin, were derived from the PGP fraction and not from the LPS itself.

Extracellular matrix remodeling in coxsackievirus B3 myocarditis

The connective tissue abnormality in relation to T lymphocytes was investigated in murine myocarditis. Inbred BALB/c-nu/+ (euthymic and normal T cell function) and BALB/c-nu/nu (athymic and T cell deficient) mice were inoculated with coxsackievirus B3 (CB3). Hearts were stained with hematoxylin-eosin, Malloryazan, and silver impregnation, for reticulin fiber abnormalities, and T lymphocyte subsets. In BALB/c-nu/+ mice, active myocardial necrosis appeared parallel with T lymphocyte infiltrates, that is, it was absent on day 0, increased until 14 days, and then decreased with time. In contrast, the abnormal reticulin fiber architecture and interstitial fibrosis increased with time until 60 days, when ventricular remodeling was noted. In the hearts of BALB/c-nu/nu mice, although minimal myocardial necrosis associated with infiltrating immature T lymphocytes was noted earlier, subsequent interstitial fibrosis and reticulin fiber abnormalities were not documented later. The abnormal reticulin fiber architecture seen in BALB/c-nu/+ mice may contribute to the extracellular matrix remodeling in murine CB3 myocarditis in which dilated cardiomyopathy develops later.

Risk factors for low bone mineral density among females: the effect of lean body mass

BACKGROUND

This study determines if body composition and lifestyle are risk factors for low radius-bone mineral density (R-BMD) and evaluates the role of body composition in the age-related decline of R-BMD.

METHODS

Data on age, menopausal status, fat mass, lean body mass (LBM), drinking, smoking, and occupation were collected from 3,867 females ages 37-69, whose R-BMD was also measured. Multiple logistic regression analyses examined the predictive accuracy of these factors for low (20th percentile) R-BMD.

RESULTS

Age, LBM, and menopausal status were risk factors for the 37-55 age group, while age, LBM, and lifestyle (alcohol consumption 3 or fewer days per week and currently smoking) were risk factors for the 56-69 age group. The odds ratio (OR) for LBM was nearly reciprocal to the ORs for age and for menopausal status. Our model has low sensitivity, high specificity, low positive predictive value, and high negative predictive value.

CONCLUSIONS

Consumption of alcohol 3 or fewer days per week and being a current smoker have a negative effect on R-BMD among older (56-69) women. The positive effect of LBM on R-BMD continues from age 37 on LBM has an effect almost equal but opposite to those of aging and menopause on the risk of low R-BMD. High LBM after age 37 predicts normal R-BMD.

Individual variation of acetohexamide reductase activities in liver microsomes and cytosol of rats

We examined individual variations in acetohexamide reductase activities in liver microsomes and cytosol of rats. Large differences among individuals were observed for acetohexamide reductase activity in liver microsomes of male Fischer-344 (Fischer), Sprague-Dawley (SD) and Wistar rats at 9 weeks of age, except in the Wistar-Imamichi (Wistar-IM) strain. These four strains of female rats did not exhibit any microsomal enzyme activity. Although acetohexamide reductase activities were fully detectable in liver cytosols from all the strains of male and female rats, there was neither strain-related difference nor considerable individual variation in the cytosolic enzyme activity. In liver microsomes of male Fischer rats at 4 weeks of age, acetohexamide reductase activity was not detectable. The microsomal enzyme activity in male Fischer rats markedly increased at 6 weeks of age to approach the levels at 9 and 12 weeks of age, with large individual variations.