High oxygen exposure's impact on newborn mice: Temporal changes observed via micro-computed tomography.

INTRODUCTION: Bronchopulmonary dysplasia (BPD) impacts life expectancy and long-term quality of life. Currently, BPD mouse models exposed to high oxygen are frequently used, but to reevaluate their relevance to human BPD, we attempted an assessment using micro-computed tomography (µCT). METHODS: Newborn wildtype male mice underwent either 21% or 95% oxygen exposure for 4 days, followed until 8 wk. Weekly µCT scans and lung histological evaluations were performed independently. RESULTS: Neonatal hyperoxia for 4 days hindered lung development, causing alveolar expansion and simplification. Histologically, during the first postnatal week, the exposed group showed a longer mean linear intercept, enlarged alveolar area, and a decrease in alveolar number, diminishing by week 4. Weekly µCT scans supported these findings, revealing initially lower lung density in newborn mice, increasing with age. However, the high-oxygen group displayed higher lung density initially. This difference diminished over time, with no significant contrast to controls at 3 wk. Although no significant difference in total lung volume was observed at week 1, the high-oxygen group exhibited a decrease by week 2, persisting until 8 wk. CONCLUSION: This study highlights µCT-detected changes in mice exposed to high oxygen. BPD mouse models might follow a different recovery trajectory than humans, suggesting the need for further optimization.

Genetic Ablation of Pyruvate Dehydrogenase Kinase Isoform 4 Gene Enhances Recovery from Hyperoxic Lung Injury: Insights into Antioxidant and Inflammatory Mechanisms.

BACKGROUND: Pyruvate dehydrogenase kinase isoform 4 (PDK4) plays a pivotal role in the regulation of cellular proliferation and apoptosis. The objective of this study was to examine whether the genetic depletion of the PDK4 gene attenuates hyperoxia-induced lung injury in neonatal mice. METHODS: Neonatal PDK4-/- mice and wild-type (WT) mice were exposed to oxygen concentrations of 21% (normoxia) and 95% (hyperoxia) for the first 4 days of life. Pulmonary histological assessments were performed, and the mRNA levels of lung PDK4, monocyte chemoattractant protein (MCP)-1 and interleukin (IL)-6 were assessed. The levels of inflammatory cytokines in lung tissue were quantified. RESULTS: Following convalescence from neonatal hyperoxia, PDK4-/- mice exhibited improved lung alveolarization. Notably, PDK4-/- mice displayed significantly elevated MCP-1 protein levels in pulmonary tissues following 4 days of hyperoxic exposure, whereas WT mice showed increased IL-6 protein levels under similar conditions. Furthermore, neonatal PDK4-/- mice subjected to hyperoxia demonstrated markedly higher MCP-1 mRNA expression at 4 days of age compared to WT mice, while IL-6 mRNA expression remained unaffected in PDK4-/- mice. CONCLUSIONS: Newborn PDK4-/- mice exhibited notable recovery from hyperoxia-induced lung injury, suggesting the potential protective role of PDK4 depletion in mitigating lung damage.

Association of hyaluronan and proteoglycan link protein 1 gene with the need of home oxygen therapy in premature Japanese infants with bronchopulmonary dysplasia.

BACKGROUND: Bronchopulmonary dysplasia (BPD) has a lasting effect on the respiratory function of infants, imposing chronic health burdens. BPD is influenced by various prenatal, postnatal, and genetic factors. This study explored the connection between BPD and home oxygen therapy (HOT), and then we examined the association between HOT and a specific single-nucleotide polymorphism (SNP) in the hyaluronan and proteoglycan link protein 1 (HAPLN1) gene among premature Japanese infants. MATERIALS AND METHODS: Prenatal and postnatal data from 212 premature infants were collected and analyzed by four SNPs (rs975563, rs10942332, rs179851, and rs4703570) around HAPLN1 using the TaqMan polymerase chain reaction method. The clinical characteristics and genotype frequencies of HAPLN1 were assessed and compared between HOT and non-HOT groups. RESULTS: Individuals with AA/AC genotypes in the rs4703570 SNP exhibited significantly higher HOT rates at discharge than those with CC homozygotes (odds ratio, 1.20, 95% confidence interval, 1.07-1.35, p = .038). A logistic regression analysis determined that CC homozygotes in the rs4703570 SNP did not show a statistically significant independent association with HOT at discharge. CONCLUSIONS: Although our study did not reveal a correlation between HAPLN1 and the onset of BPD, we observed that individuals with CC homozygosity at the rs4703570 SNP exhibit a reduced risk of HOT.

Bronchopulmonary Dysplasia in Extremely Premature Infants: A Scoping Review for Identifying Risk Factors.

BACKGROUND: Over the years, bronchopulmonary dysplasia (BPD) affects the pulmonary function of infants, resulting in chronic health burdens for infants and their families. The aim of this scoping review was to screen available evidence regarding perinatal risk factors associated with the development and severity of BPD. METHODS: The eligibility criteria of the studies were year of publication between 2016 and 2021; setting of a developed country; English or Japanese as the study language; and randomized controlled, cohort, or case-control design. The titles and abstracts of the studies were screened by independent reviewers. RESULTS: Of 8189 eligible studies, 3 were included for severe BPD and 26 were included for moderate BPD. The risk factors for severe BPD were male sex, iatrogenic preterm birth, maternal hypertensive disorders of pregnancy (HDP), low gestational age, small-for-gestational-age (SGA) birth weight, mechanical ventilation on day 1, and need for patent ductus arteriosus (PDA) management. The risk factors for moderate or severe BPD included male sex, premature rupture of membranes, clinical chorioamnionitis, maternal HDP, SGA birth weight, bubbly/cystic appearance on X-ray, and PDA management. CONCLUSIONS: We identified several risk factors for BPD. We plan to confirm the validity of the new classification using the existing dataset.

Use of pleural cryobiopsy for tissue culture specimens: a case report.

A 43-year-old man presented with cough. His chest X-ray showed a left-sided pleural effusion. We suspected tuberculous pleurisy (TP), and thoracoscopy under local anaesthesia was performed. It showed entire pleura with scattered nodules. Nodules were biopsied by conventional biopsy forceps, but the tissue sample was small. Therefore, the nodules were biopsied with a cryoprobe. The tissue size obtained was 2 mm by conventional biopsy forceps, and 6 mm at 5 sec by cryobiopsy. Histological analysis of the conventional biopsy forceps and cryobiopsy specimen showed inflammation with lymphocytes and caseating granulomas. Tissue culture of conventional biopsy forceps was positive for Mycobacterium tuberculosis, and all sensitivity tests were positive. But, the tissue culture of the cryobiopsy sample was negative. There is a possibility that cryobiopsy is not useful for tissue culture for TP.

Study protocol for a nationwide questionnaire survey of physical activity among breast cancer survivors in Japan.

INTRODUCTION: A major concern is that few cancer survivors meet the guidelines for recommended levels of physical activity. No studies have investigated physical activity among breast cancer survivors nationwide in Japan. Therefore, the aims of this study are to identify the levels of physical activity among breast cancer survivors, to examine factors-related physical activity among breast cancer survivors and to identify breast cancer survivors' preferences for and interest in exercise programmes in order to inform the future programme development. METHODS AND ANALYSIS: We will administer a cross-sectional survey using a self-report questionnaire to breast cancer survivors. At each of 50 facilities selected to include a variety of institutional backgrounds according to the population distribution of different regions throughout Japan, we will consecutively distribute the questionnaire to 30 outpatients who have completed initial treatments, except for hormone therapy. The target sample size is 1500 survivors. We will calculate descriptive statistics for each measurement item and perform univariate and multivariate analyses using outcome measures (eg, physical activity and quality of life) related to physical, psychological, social and environmental factors. DISCUSSION: This is the first nationwide survey of physical activity levels among breast cancer survivors in Japan. Identifying the factors associated with physical activity will help us to develop, disseminate and implement programmes that encourage more survivors to adhere to physical activity guidelines. ETHICS AND DISSEMINATION: The protocol was approved by the Institutional Review Board (IRB) of the National Cancer Center on 11 January 2019 (ID: 2018-295). In addition, many of the participating facilities required ethical approval from their local IRBs, while others did not. Accordingly, approval from the local IRBs of individual facilities was obtained when required. The findings will be disseminated through peer-reviewed publications and conference presentations.

An Early-Onset Neuronopathic Form of Acid Sphingomyelinase Deficiency: A SMPD1 p.C133Y Mutation in the Saposin Domain of Acid Sphingomyelinase.

Acid sphingomyelinase (ASM) is a lysosomal hydrolase that degrades sphingomyelin into ceramide and phosphocholine. Recent crystallographic studies revealed the functional role of the N-terminal ASM saposin domain. ASM deficiency due to mutations in the ASM-encoding sphingomyelin phosphodiesterase 1 (SMPD1) gene causes an autosomal recessive sphingolipid-storage disorder, known as Niemann-Pick disease Type A (NPA) or Type B (NPB). NPA is an early-onset neuronopathic disorder, while NPB is a late-onset non-neuronopathic disorder. A homozygous one-base substitution (c.398G>A) of the SMPD1 gene was identified in an infant with NPA, diagnosed with complete loss of ASM activity in the patient's fibroblasts. This mutation is predicted to substitute tyrosine for cysteine at amino acid residue 133, abbreviated as p.C133Y. The patient showed developmental delay, hepatosplenomegaly and rapid neurological deterioration leading to death at the age of 3 years. To characterize p.C133Y, which may disrupt one of the three disulfide bonds of the N-terminal ASM saposin domain, we performed immunoblotting analysis to explore the expression of a mutant ASM protein in the patient's fibroblasts, showing that the protein was detected as a 70-kDa protein, similar to the wild-type ASM protein. Furthermore, transient expression of p.C133Y ASM protein in COS-7 cells indicated complete loss of ASM enzyme activity, despite that the p.C133Y ASM protein was properly localized to the lysosomes. These results suggest that the proper three-dimensional structure of saposin domain may be essential for ASM catalytic activity. Thus, p.C133Y is associated with complete loss of ASM activity even with stable protein expression and proper subcellular localization.

Bubbly and cystic appearance on chest radiograph of extremely preterm infants with bronchopulmonary dysplasia is associated with wheezing disorder.

AIM: Bubbly/cystic appearance on chest X-ray (CXR) is an important factor in cases of severe bronchopulmonary dysplasia (BPD). We aimed to determine whether CXR -based BPD classifications obtained in extremely preterm infants with oxygen dependency at 28 days after birth (BPD28) is associated with wheezing disorders. METHODS: This was a multicentre retrospective cohort study of population data from infants (body weight, <1500 g) enrolled in the Neonatal Research Network of Japan. Of the 15 480 infants born at <28 weeks of gestation between 2003 and 2012, 8979 met the BPD28 criteria, and 4007 were classified as the no BPD28 group. BPD28 infants were classified according to the bubbly/cystic or no bubbly/cystic appearance on CXR at postnatal ≧28 days. The effects on wheezing disorder at 3 years of age were analysed. RESULTS: Bubbly/cystic BPD28 infants showed higher rates of wheezing disorders compared with no BPD28 infants. Bubbly/cystic BPD28 (odds ratio 1.7; 95% confidence interval, 1.3-2.2) was a significant independent factor for wheezing disorders. CONCLUSION: A bubbly/cystic appearance on CXR with BPD28 was a potential risk factor of wheezing disorders at 3 years of age. This may be a useful early diagnostic tool at ≧28 postnatal days in extremely preterm infants.

Impact of chest radiography-based definition of bronchopulmonary dysplasia.

BACKGROUND: Bubbly/cystic appearance on chest radiograph is an important factor in severe-type bronchopulmonary dysplasia (BPD) in Japan. The aim of this study was to determine the perinatal characteristics and neonatal complications of the bubbly/cystic(+) group in extremely preterm infants with BPD, that is, oxygen dependency at day 28 after birth (BPD28). METHODS: This was a multicenter retrospective cohort study of population data from infants (birthweight, <1,500 g) enrolled in the Neonatal Research Network of Japan. Of the 15 480 infants born at <28 weeks' gestational age (GA) between 2003 and 2012, 8,979 met the BPD28 criteria. The BPD28 infants were classified according to bubbly/cystic appearance on radiograph (±) at >28 postnatal days. RESULTS: The bubbly/cystic(+) group had lower GA and birthweight and required longer mechanical ventilation and oxygen dependency than the bubbly/cystic(-) group. After adjustment for confounding factors, bubbly/cystic appearance was an independent risk factor for home oxygen therapy at discharge. CONCLUSION: Bubbly/cystic appearance on chest radiograph was a predictor of short-term respiratory outcomes in infants with BPD28, which is diagnosed much earlier (≥28 postnatal days), and has a potentially different etiology to BPD36 (oxygen and/or positive pressure respiratory support dependency at 36 weeks' postmenstrual age).

Discovery of a novel 2-(1H-pyrazolo[3,4-b]pyridin-1-yl)thiazole derivative as an EP1 receptor antagonist and in vivo studies in a bone fracture model.

We describe a medicinal chemistry approach to the discovery of a novel EP1 antagonist exhibiting high potency and good pharmacokinetics. Our starting point is 1, an EP1 receptor antagonist that exhibits pharmacological efficacy in cystometry models following intravenous administration. Despite its good potency in vitro, the high lipophilicity of 1 is a concern in long-term in vivo studies. Further medicinal chemistry efforts identified 4 as an improved lead compound with good in vitro ADME profile applicable to long term in vivo studies. A rat fracture study was conducted with 4 for 4 weeks to validate its utility in bone fracture healing. The results suggest that this EP1 receptor antagonist stimulates callus formation and thus 4 has potential for enhancing fracture healing.

A series of novel indazole derivatives of Sirt 1 activator as osteogenic regulators.

A series of indazole derivatives were identified as Sirt 1 activators though high-throughput screening. Optimization of each substituent on the indazole ring led to the identification of compound 13. Compound 13 appeared to give the best Sirt 1 activity of the compounds tested and also showed osteogenesis activity in a cell assay. Sirt 1 activators are therefore potential candidates for the treatment of osteoporosis.

NCI-H295R, a human adrenal cortex-derived cell line, expresses purinergic receptors linked to Ca²âº-mobilization/influx and cortisol secretion.

Purinergic receptor expression and involvement in steroidogenesis were examined in NCI-H295R (H295R), a human adrenal cortex cell line which expresses all the key enzymes necessary for steroidogenesis. mRNA/protein for multiple P1 (A(2A) and A(2B)), P2X (P2X5 and P2X7), and P2Y (P2Y1, P2Y2, P2Y6, P2Y12, P2Y13, and P2Y14) purinergic receptors were detected in H295R. 2MeS-ATP (10-1000 µM), a P2Y1 agonist, induced glucocorticoid (GC) secretion in a dose-dependent manner, while other extracellular purine/pyrimidine agonists (1-1000 µM) had no distinct effect on GC secretion. Extracellular purines, even non-steroidogenic ones, induced Ca²âº-mobilization in the cells, independently of the extracellular Ca²âº concentration. Increases in intracellular Ca²âº concentration induced by extracellular purine agonists were transient, except when induced by ATP or 2MeS-ATP. Angiotensin II (AngII: 100 nM) and dibutyryl-cyclic AMP (db-cAMP: 500 µM) induced both GC secretion and Ca²âº-mobilization in the presence of extracellular Ca²âº (1.2 mM). GC secretion by AngII was reduced by nifedipine (10-100 µM); whereas the Ca²âº channel blocker did not inhibit GC secretion by 2MeS-ATP. Thapsigargin followed by extracellular Ca²âº exposure induced Ca²âº-influx in H295R, and the cells expressed mRNA/protein of the component molecules for store-operated calcium entry (SOCE): transient receptor C (TRPC) channels, calcium release-activated calcium channel protein 1 (Orai-1), and the stromal interaction molecule 1 (STIM1). In P2Y1-knockdown, 2MeS-ATP-induced GC secretion was significantly inhibited. These results suggest that H295R expresses a functional P2Y1 purinergic receptor for intracellular Ca²âº-mobilization, and that P2Y1 is linked to SOCE-activation, leading to Ca²âº-influx which might be necessary for glucocorticoid secretion.

Structural equation modeling for implementation intentions, cancer worry, and stages of mammography adoption.

OBJECTIVES: This study aimed to develop a structural model for mammography adoption in Japanese middle-aged women by using constructs from the transtheoretical model (TTM), the theory of planned behavior (TPB), implementation intentions, and cancer worry. METHODS: Questionnaires based on items including TTM, TPB, implementation intentions, cancer worry-related variables, and demographic variables were distributed to 1000 adult women aged 40 to 59 years, with 641 subjects being used in the final analysis (response rate = 64.1%). RESULTS: Regarding the stage of adoption, 79 participants (12.3%) were at the precontemplation stage, 30 (4.7%) were at the relapse stage, 142 (22.2%) were at the contemplation stage, 88 (13.7%) were at the action stage, and 302 (47.1%) were at the maintenance stage. Our model, derived from structural equation modeling, revealed that the stage of mammography adoption was significantly affected by goal intentions, implementation intentions, perceived barriers, history of breast cancer screening, and relative risk. A logistic regression analysis revealed that goal intentions and implementation intentions significantly predicted mammography uptake within 1 year. CONCLUSION: This study developed an integrated model constructed from TTM, TPB, implementation intentions, and cancer worry to account for mammography adoption in Japan, and also confirmed the predictive validity of the model.

Worry and intention among Japanese women: implications for an audience segmentation strategy to promote mammography adoption.

We examined the predictive validity of a segmentation strategy based on intention and cancer worry for mammography adoption and explored key factors for promoting mammography adoption in each segment. A questionnaire survey was completed by 641 women aged 40-59 years. Among them, 559 answered a follow-up survey after 15 months. They were categorized into five segments: maintenance group (S5), higher implementation intention group (S4), higher goal intention group (S3), higher worry group (S2), or lower worry group (S1). The odds of participants in each segment adopting mammography during the follow-up period were calculated. Logistic regression analysis was conducted to identify psychological predictors (five attitudes to mammography and perceived health competence) of transition to upper segments (S1 vs. S2, S2 vs. S3, S3 vs. S4, S4 vs. S5). Compared to S5, other segments did not undertake mammography at significant rates during the follow-up. The following were significant predictors for inclusion in upper segments: Lack of importance and perceived health competence were associated with inclusion in S2; lack of importance and barriers to screening were associated with inclusion in S3; perceived health competence was associated with inclusion in S4; and lack of importance was associated with inclusion in S5. These results confirm the predictive validity of a segmentation strategy, and indicate that there might be specific key factors for each segment in promoting mammography adoption.

Congenital hyperinsulinism in an infant with paternal uniparental disomy on chromosome 11p15: few clinical features suggestive of Beckwith-Wiedemann syndrome.

Beckwith-Wiedemann syndrome (BWS) is the most common congenital overgrowth syndrome involving tumor predisposition. BWS is caused by various epigenetic or genetic alterations that disrupt the imprinted genes on chromosome 11p15.5 and the clinical findings of BWS are highly variable. Hyperinsulinemic hypoglycemia is reported in about half of all babies with BWS. We identified an infant with diazoxide-unresponsive congenital hyperinsulinism (HI) without any apparent clinical features suggestive of BWS, but diagnosed BWS by molecular testing. The patient developed severe hyperinsulinemic hypoglycemia within a few hours after birth, with macrosomia and mild hydronephrosis. We excluded mutations in the K(ATP) channel genes on chromosome 11p15.1, but found a rare homozygous single nucleotide polymorphism (SNP) of ABCC8. Parental SNP pattern suggested paternal uniparetal disomy in this region. By microsatellite marker analysis on chromosome 11p15, we could diagnose BWS due to the mosaic of paternal uniparental disomy. Our case suggests that some HI of unknown genetic etiology could involve undiagnosed BWS with no apparent clinical features, which might be diagnosed only by molecular testing.

Hypoxia-ischemia induces hypo-phosphorylation of collapsin response mediator protein 2 in a neonatal rat model of periventricular leukomalacia.

Collapsin response mediator protein2 (CRMP2) is a brain-specific protein involved in neuronal polarity and axonal guidance, and phosphorylation of CRMP2 regulates the function and the activity. CRMP2 has shown to be implicated in several neurodegenerative diseases (Alzheimer's disease, epilepsy and ischemia) and this study was designed to assess the role of CRMP2 in periventricular leukomalacia (PVL). We developed a PVL model using 3-day-old rats to investigate the expression and phosphorylation of CRMP2 in the newborn brain. Hypoxia-ischemia was applied by unilateral carotid ligation followed by exposure to 5% oxygen for 30min. Pathological changes were evaluated from 0h to 21d post-HI, and white matter damage including severe necrosis, white matter rarefaction and lateral ventricle dilatation were found. In the PVL model astrogliosis and axonal damage were detected in the injured white matter by immunohistochemistry at 48-168h post-HI, and delayed myelination was verified by Western blotting after 21-day post-HI. We confirmed that this model showed neuropathological features of PVL. Next, significant changes of CRMP2 were observed in the brain of the PVL model. Western blotting and immunohistochemistry showed that cleavage and hypo-phosphorylation of CRMP2 occurred after 48h post-HI in the PVL brain. Our results suggest that cleaved CRMP2 could represent hypo-phosphorylated-CRMP2 and HI could induce activation of CRMP2 in the PVL brain. The activated CRMP2 may play an important role in neuronal plasticity in PVL. Our findings suggest that future treatment strategies of PVL should target the phosphorylation mechanism of CRMP2.

Self-efficacy, psychological adjustment and decisional-balance regarding decision making for outpatient chemotherapy in Japanese advanced lung cancer.

This study examined the application of the trans-theoretical model (TTM) for readiness for decision-making of outpatient chemotherapy of Japanese advanced lung cancer patients by a cross sectional questionnaire survey. A questionnaire was conducted with 105 Japanese patients diagnosed with advanced lung cancer receiving chemotherapy. We classified them according to the TTM stages, including 4 in precontemplation, 42 in contemplation, 22 in preparation, and 35 in action. The valid model (chi(2) (37) = 42.56, p = 0.24; GFI = 0.93; AGFI = 0.88; CFI = 0.98; RMSEA = 0.04; AIC = 100.56) derived from structural equation modeling (SEM) revealed that stage of outpatient chemotherapy was significantly affected mostly by decisional-balance (beta = 0.60, p < 0.001) and partially by time from the patient's house to the hospital (beta = -0.15, p < 0.10), and that decisional-balance was significantly affected by self-efficacy (beta = 0.48, p < 0.001) and nausea (beta = -0.23, p < 0.01). The findings from our study provided encouraging results for adopting the TTM in decision making for outpatient chemotherapy in Japanese cancer care and several clinical implications were obtained from the results.

Discrimination between worry and anxiety among cancer patients: development of a Brief Cancer-Related Worry Inventory.

OBJECTIVES: A psychometric scale for assessing cancer-related worry among cancer patients, called the Brief Cancer-Related Worry Inventory (BCWI), was developed. METHODS: A cross-sectional questionnaire survey for item development was conducted of 112 Japanese patients diagnosed with breast cancer, and test-retest validation analysis was conducted using the data from another prospective study of 20 lung cancer patients. The questionnaire contained 15 newly developed items for cancer-related worry, the Hospital Anxiety and Depression Scale, The Impact of Event Scale Revised, and the Medical Outcomes Study Short Form-8. RESULTS: Exploratory factor analysis of the 15 items yielded a 3-factor structure including (1) future prospects, (2) physical and symptomatic problems and (3) social and interpersonal problems. A second-order confirmatory factor analysis identified a second-order factor called cancer-related worry and confirmed the factor structure with an acceptable fit (chi-square (df=87)=160.16, P=0.001; GFI=0.83; CFI=0.92; RMSEA=0.09). The internal consistency and test-retest reliability were confirmed with the lung cancer sample. Multidimensional scaling found that cancer-related worry is separate from anxiety, depression, and posttraumatic stress disorder (PTSD) symptoms. CONCLUSION: Our study succeeded in developing and confirming the validity and reliability of a BCWI. The study also confirmed the discriminable aspects of cancer-related worry from anxiety, depression, and PTSD symptoms.

Osteopontin expression in the liver with severe perisinusoidal fibrosis: autopsy case of Down syndrome with transient myeloproliferative disorder.

Down syndrome with transient myeloproliferative disorder (TMD) is often associated with perinatal liver fibrosis. The authors recently encountered an autopsy case of this disease with a characteristic severe perisinusoidal liver fibrosis. Osteopontin (OPN) is a molecule that plays an important role in diverse fibro-inflammatory diseases. The purpose of the present report was to examine the involvement of OPN in development of the Down syndrome-associated liver fibrosis. Histology indicated severe perisinusoidal fibrosis and ductular arrangements of hepatocytes in the liver. Appearance of atypical megakaryocytes in the liver, a feature of TMD associated with Down syndrome, was not evident. On immunohistochemistry expression of OPN was observed in hepatocytes often having ductular arrangements and infiltrating macrophages. In contrast, a small number of transforming growth factor-beta1 (TGF-beta1)-positive mononuclear cells were present in the liver. Numerous activated hepatic stellate cells (HSC) expressing alpha-smooth muscle actin (alpha-SMA) were seen in the perisinusoidal area. A recent report indicated that OPN could directly activate the HSC. Thus, it is suggested that OPN produced by hepatocytes and macrophages induces activation of the HSC, and leads to the development of perisinusoidal liver fibrosis.