Predictors of a Good Diuretic Response and Administration Methods for Carperitide in Patients With Acute Heart Failure

PURPOSE

In Japan, carperitide has been recommended for the treatment of pulmonary congestion in patients with acute heart failure. Identifying useful indicators to support the decision to administer carperitide and the optimal timing of administration may lead to better improvement of pulmonary congestion. Therefore, we investigated the factors associated with good diuretic response to carperitide in patients with acute heart failure and the optimal timing of carperitide administration.

METHODS

This retrospective cohort study investigated 293 hospitalized patients who were diagnosed with acute heart failure and treated with carperitide at the Department of Cardiology, Showa University Fujigaoka Hospital. The primary endpoint was the diuretic response to carperitide. Patients with urine output ≥100 mL/h were defined as the good diuretic response group, and those with a urine output <100 mL/h during the first 6 hours of carperitide administration were defined as the poor diuretic response group. Multivariate analysis was used to examine the predictors of good diuretic response. The relationship between the time from intravenous furosemide to carperitide administration and urine output was also investigated.

FINDINGS

The patients' median age was 77 (range: 28-99) years, and 75.5% had New York Heart Association stage IV acute heart failure. The median urine output within 6 hours of carperitide administration was 104.5 (range: 6.6-1571.3) mL/h, and 118 patients (53.6%) showed a good diuretic response. Significant predictors of good diuretic response were age < 75 years [odds ratio (OR) 4.186; 95% confidence interval (CI), 2.129-8.230; P < 0.001], no prior use of loop diuretics (OR 2.155; 95% CI, 1.104-4.207; P = 0.024), blood urea nitrogen <20 mg/dL (OR 2.637; 95% CI, 1.340-5.190; P = 0.005), and white blood cell count <8.6 × 109/L (OR 3.162; 95% CI, 1.628-6.140; P = 0.001). The median urine output in the group with <2 hours between intravenous furosemide and carperitide administration was significantly higher than that in the group with an interval >6 hours [127.3; interquartile range (IQR), 77.6-216.2 mL/h vs. 66.2; IQR. 51.8-114.8 mL/h; P = 0.012).

IMPLICATIONS

The 4 predictors (age, no prior use of loop diuretics, blood urea nitrogen, and white blood cell count) of good diuretic response are useful indicators to support decision-making for carperitide administration. Additionally, the administration of carperitide within 2 hours of intravenous furosemide may lead to the improvement of pulmonary congestion.

Factors associated with readmission after long-term administration of tolvaptan in patients with congestive heart failure

Introduction

We investigated the factors associated with readmission in patients with congestive heart failure (HF) receiving long-term administration of tolvaptan (TLV) to support treatment decisions for HF.

Methods

This retrospective cohort study included 181 patients with congestive HF who received long-term administration of TLV. Long-term administration of TLV was defined as the administration of TLV for 60 days or longer. The outcome was a readmission event for worsening HF within 1 year after discharge. Significant factors associated with readmission were selected using multivariate analysis. To compare the time to readmission using significant factors extracted in a multivariate analysis, readmission curves were constructed using the Kaplan-Meier method and analysed using the log-rank test.

Results

The median age was 78 years (range, 38-96 years), 117 patients (64.6%) were males, and 77 patients (42.5%) had a hospitalisation history of HF. Readmission for worsening HF within 1 year after long-term TLV treatment occurred in 62 patients (34.3%). In the multivariate analysis, estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m2 (odds ratio, 3.22; 95% confidence interval, 1.661-6.249; P = 0.001) was an independent significant factor. When eGFR at discharge was divided into two groups (eGFR < 30 vs. eGFR ≥ 30), readmission rates within 1 year were 53.3% vs. 25.4%, respectively (P = 0.001).

Conclusion

We revealed that eGFR was strongly associated with readmission in patients with HF who received long-term administration of TLV. Furthermore, we showed that eGFR is an important indicator in guiding treatment of HF in patients receiving TLV.

Development of a model predicting cardiac events in heart failure patients with decreased renal function: a retrospective study

BACKGROUND

Inappropriate and multiple medications affect the prognosis of patients with acute decompensated heart failure (ADHF). However, in ADHF patients with decreased renal function, there have been no reports on prognostic factors, including medication data, or models for predicting cardiac events.

AIM

To develop a model including medication data to predict cardiac events in ADHF patients with decreased renal function.

METHOD

This retrospective cohort study included 443 first-time admitted ADHF patients with decreased renal function (estimated glomerular filtration rate < 60 mL/min/1.73 m² at discharge) in the Showa University Fujigaoka Hospital. The primary outcome was cardiac events within one year after discharge, defined as the composite of HF readmission, HF mortality, and cardiovascular mortality. The model for predicting cardiac events was developed using predictive factors extracted by multivariable analysis. The cardiac events curves were visualized using the Kaplan-Meier method and estimated using a log-rank test.

RESULTS

The incidence of cardiac events within one year after discharge was 20.1%. By multivariable analysis, we observed that atrial fibrillation, weight loss < 5%, brain natriuretic peptide ≥ 200 pg/mL, polypharmacy, and beta-blockers use below target dosage were significantly associated with an increased risk of cardiac events. The developed model, the cardiac events rate in the high-risk group was significantly higher than in the low-risk group (41.0 vs. 9.2%, p < 0.001).

CONCLUSION

The developed model for predicting cardiac events will be useful in decision-making to support appropriate early management of ADHF patients with decreased renal function.

Prognostic model for overall survival that includes the combination of platelet count and neutrophil-lymphocyte ratio within the first six weeks of sunitinib treatment for metastatic renal cell carcinoma

BACKGROUND

The association between the combination of platelet count and neutrophil-lymphocyte ratio (COP-NLR) at the time of adverse events during sunitinib treatment and prognosis is unclear, and prognostic models combining the prognostic factors of sunitinib have not been well studied. Thus, we developed a prognostic model that includes the COP-NLR to predict the prognosis of patients with metastatic renal cell carcinoma (mRCC) treated with sunitinib.

METHODS

We performed a retrospective cohort study of 102 patients treated with sunitinib for mRCC between 2008 and 2020 in three hospitals associated with Showa University, Japan. The primary outcome was overall survival (OS). The collected data included baseline patient characteristics, adverse events, laboratory values, and COP-NLR scores within the first 6 weeks of sunitinib treatment. Prognostic factors of OS were analyzed using the Cox proportional hazards model. The integer score was derived from the beta-coefficient (β) of these factors and was divided into three groups. The survival curves were visualized using the Kaplan-Meier method and estimated using a log-rank test.

RESULTS

The median OS was 32.3 months. Multivariable analysis showed that the number of metastatic sites, Memorial Sloan Kettering Cancer Center risk group, number of metastases, non-hypertension, modified Glasgow Prognostic Score, and 6-week COP-NLR were significantly associated with OS. A higher 6-week COP-NLR was significantly associated with a shorter OS (p < 0.001). The β values of the five factors for OS were scored (non-hypertension, mGPS, and 6-week COP-NLR = 1 point; number of metastatic sites = 2 points; MSKCC risk group = 3 points) and patients divided into three groups (≤ 1, 2-3, and ≥ 4). The low-risk (≤ 1) group had significantly longer OS than the high-risk (≥ 4) group (median OS: 99.0 vs. 6.2 months, p < 0.001).

CONCLUSIONS

This study showed that the COP-NLR within the first 6 weeks of sunitinib treatment had a greater impact on OS than the COP-NLR at the start of sunitinib treatment. The developed prognostic model for OS, including the 6-week COP-NLR, will be useful in decision-making to continue sunitinib in the early treatment stage of patients with mRCC.

Factors associated with a reduction in the quality of life of patients with chronic hepatitis C treated by ledipasvir/sofosbuvir therapy

OBJECTIVE

We investigated factors associated with a reduction in the quality of life and their OR of patients with chronic hepatitis C who underwent ledipasvir/sofosbuvir therapy.

METHODS

The subjects were 141 outpatients who had undergone ledipasvir/sofosbuvir therapy under a diagnosis of genotype I chronic hepatitis C or Child-Pugh A compensated cirrhosis at Hitachi General Hospital. The patient background before ledipasvir/sofosbuvir therapy, laboratory data and the Chronic Liver Disease Questionnaire scores during ledipasvir/sofosbuvir therapy were investigated. The Chronic Liver Disease Questionnaire consists of 29 questions, and the mean value is calculated as the overall score through a 7-step assessment by patients. Using two divisions: a Chronic Liver Disease Questionnaire score of <7 (symptoms are present) and that of 7 (no symptoms), as objective variables, patients with a Chronic Liver Disease Questionnaire score of <7 were defined as having a reduced quality of life. Independent factors significantly associated with a reduction in the quality of life were extracted using logistic regression analysis.

RESULTS

Based on the multivariate analysis, an alanine aminotransferase level of ≥23 U/L (OR: 4.380, 95% CI: 1.394 to 13.756) was extracted as an independent factor associated with a reduction in the quality of life (p<0.05).

CONCLUSION

An increase in the baseline level of alanine aminotransferase was found to play a role in the reduction in the quality of life of patients with chronic hepatitis C who had undergone ledipasvir/sofosbuvir therapy.

Scoring Model to Predict a Low Disease Activity in Elderly Rheumatoid Arthritis Patients Initially Treated with Biological Disease-modifying Antirheumatic Drugs

Objective We aimed to develop a scoring model to predict a low disease activity (LDA) in elderly rheumatoid arthritis (RA) patients initially treated with biological disease-modifying antirheumatic drugs (bDMARDs). Methods This retrospective cohort study included 82 elderly RA patients who initially received bDMARDs. The outcome was an LDA after bDMARDs initiation. We developed a predictive formula for an LDA using a multivariate analysis, the accuracy of which was assessed by the area under the curve (AUC) of the receiver operating characteristic curves; the scoring model was developed using the formula. For each factor, approximate odds ratios were scored as an integer, divided into three groups based on the distribution of these scores. In addition, the scoring model accuracy was assessed. Results The mean age was 73.5±6.0 years old, and 86.6% were women. An LDA was achieved in 43 patients (52.4%). The predictive formula for an LDA was prepared using six factors selected for the multivariable analysis: the neutrophil-to-lymphocyte ratio (NLR), anemia, the 28-joint disease activity score with erythrocyte sedimentation rate (DAS28-ESR), serum level of matrix metalloproteinase-3 (MMP-3), diabetes mellitus (DM), and rheumatoid factor (RF). The AUC for the formula was 0.829 (95% confidence interval, 0.729-0.930). The odds ratios of the six factors were scored (DAS28-ESR and serum MMP-3=1 point, NLR, anemia, DM, and RF=2 points) and divided into three groups (≤4, 5-7, and ≥8). The high-score group (≥8) achieved a positive predictive value of 83%. Conclusion The scoring model accurately predicted an LDA in elderly RA patients initially treated with bDMARDs.

[Rubric Assessment for Pharmacotherapy in Spiral Curriculum: Development and Usefulness Evaluation]

A requirement, which students must satisfy, for a diploma at the Showa University School of Pharmacy is the ability to "plan, practice, and assess pharmacotherapy". To continuously assess the ability of students to meet this requirement and to provide patients with proper pharmacotherapy during student clinical rotations, we formulated the "Rubric assessment for pharmacotherapy" and evaluated its usefulness in tutorial learning classes. Clinical pharmacy faculty members created the rubric based on the Subjective, Objective, Assessment, and Plan (SOAP) note guidelines of the university. Third- (2016) and fourth-year students (2017) were required to self-assess their SOAP notes to analyze six clinical cases using the rubric. The rubric consists of three domains: (1) Evaluation of patient condition, (2) Proposal of pharmacotherapy, and (3) Plan for an assessment of pharmacotherapy. The rubric comprises 31 subdomains and is evaluated according to four levels of performance. In this study, 978 rubric sheets that were used by students to evaluate their own SOAP notes were analyzed. We found that the students were able to continuously self-assess their performance using the rubric while continuously improving their achievement level (p<0.05). The results of this study suggest that rubric assessments may be used as a tool for supporting students to plan, practice, and assess pharmacotherapy.

[QOL Assessment in Chronic Hepatitis C Patients Receiving Ledipasvir/ Sofosbuvir or Simeprevir/Peginterferon/Ribavirin in Clinical Practice]

Recently, a clinical study using a Chronic Liver Disease Questionnaire (CLDQ) showed that ledipasvir/sofosbuvir (LDV/SOF)-treated patients' QOL was more favorable than that of IFN/ribavirin (RBV)-treated patients. However, no study has reported QOL assessment in clinical practice. In this study, we compared the QOL between patients treated with LDV/SOF and those treated with simeprevir (SMV)/peginterferon (Peg-IFN)/RBV to provide QOL information in clinical practice. The subjects were 169 patients with type I chronic hepatitis C or compensated cirrhosis C (Child-Pugh Grade A) who were treated with SMV/Peg-IFN/RBV or LDV/SOF in Hitachi General Hospital. The QOL was assessed ≥2 weeks after the start of administration using the Japanese version of the CLDQ (Kida et al., 2008 version). The total CLDQ score in the LDV/SOF group was significantly higher than in the SMV/Peg-IFN/RBV group (6.59 vs. 6.38, respectively, p=0.007). In particular, the scores for 4 domains (abdominal symptoms, systemic symptoms, activity, and emotional function) in the former were significantly higher than in the latter (p<0.05). Furthermore, the rates of patients scoring 7 (no symptom) on 8 items in the former were significantly higher than in the latter (p<0.05). In clinical practice, LDV/SOF-treated patients' QOL was more favorable than that of those receiving conventional treatment with IFN and RBV. This study may make it possible for health care professionals to provide clinical QOL information on LDV/SOF therapy to patients. Furthermore, QOL information may promote decision-making for treatment, leading to effective treatment.

Analysis of Fungal Flora in the Dust of Bedding in Japanese Houses and Genetic Identification of Yeasts Isolated from the Dust

This study examined the fungal flora contained in the dust of bedding used in 50 houses in Japan. The result showed that the mycoflora having the largest isolation rate was yeasts, which were isolated by 42 out of 50 houses (84%), and exceeded the isolation rate of Cladosporium spp. (80%) and Aspergillus spp. (66%). In addition, the isolation rate of Alternaria, which was an important fungus causing asthma, 66% was being considered as a high isolation rate, and this result was very interesting. The isolation rate of xerophilic fungi such as Aspergillus restrictus and Wallemia often found in house dust on the floor, was not very high. Forty-one strains of yeasts isolated from each dust sample were identified, and Naganishia diffluens species complex and Filobasidium magnum had a larger number of 13 strains, respectively. Since N. diffluens was the yeasts often isolated from human skin, it was thought to be an association between the fungal skin flora and fungal flora of bed dust. Meanwhile, there was no report of isolation of F. magnum from house dust previously. To the best of our knowledge, this is the first study showing its isolation from bedding with relatively high frequency.

The exploration of population pharmacokinetic model for meropenem in augmented renal clearance and investigation of optimum setting of dose

In recent years, augmented renal clearance (ARC), in which renal function is excessively enhanced, has been reported, and its influence on β-lactam antibiotics has been investigated. In this study, we aimed to determine the optimum population pharmacokinetic model of meropenem in patients with sepsis with ARC, and evaluated dosing regimens based on renal function. Seventeen subjects (6 with ARC and 11 without) were enrolled in this study. Predicted meropenem concentrations were evaluated for bias and precision using the Bland-Altman method. To examine the dosing regimen, Monte Carlo simulation was performed to calculate the cumulative fraction of response (CFR). In patients with ARC, the bias (average of the predicted value and measured value residuals) of models constructed by Crandon et al. (2011), Roberts et al. (2009), and Jaruratanasirikul et al. (2015) were 5.96 μg/mL, 10.91 μg/mL, and 4.41 μg/mL, respectively. Following 2 g meropenem every 8 h (180 min infusion), CFR ≥ 90%, a criterion of success for empirical therapy, was achieved, even with creatinine clearance of 130-250 mL/min. For patients with sepsis and ARC, the model of Jaruratanasirikul et al. showed the highest degree of accuracy and precision and confirmed the efficacy of the meropenem dosing regimen in this patient population.

Flavonoid compounds related to seed coat color of wheat

In red wheat, reddish-brown pigments accumulate in testa of mature seeds. Half-cut wheat seeds were immersed in p-dimethylaminocinnamaldehyde (DMACA) reagent that stains flavanol structures blue. Testa of 10-40 days after flowering (DAF) in red wheat ("Norin 61" and "Satonosora") seeds were stained blue and the reagent color changed to blue with 10-25 DAF seeds. No blue staining was observed in white wheat ("Tamaizumi") seeds during maturation. "Norin 61" seed coats at 10 DAF contained dihydroquercetin, dihydromyricetin, (+)-catechin, procyanidin B3, and prodelphinidin B3, which were identified by HPLC-diode array detector and LC-MS/MS analyses. These five components began accumulating 7 DAF, reached maxima at 10 or 15 DAF, and then decreased in red wheat seeds, but were not detected in white wheat seeds. These results suggest that flavanol and proanthocyanidins are possible precursors of the reddish-brown pigments of red wheat seeds, and are converted to insoluble compounds as the seeds mature.

Effects of high β-glucan barley on visceral fat obesity in Japanese individuals: A randomized, double-blind study

OBJECTIVE

The aim of this study was to investigate whether a diet in which high β-glucan barley was substituted for rice would reduce visceral fat obesity in Japanese individuals.

METHODS

A randomized, double-blind, placebo-controlled intervention study was conducted with 100 Japanese individuals with waist circumference (WC) ≥85 cm for men or ≥90 cm for women and body mass index (BMI) ≥24 kg/m². Participants were randomly assigned to consume a mixture of rice and either high β-glucan barley (test group, 4.4 g/d) or β-glucan-free barley (placebo group) for 12 wk. Blood samples and computed tomography scans were obtained before and after the trial.

RESULTS

Both groups showed decreases in body weight and BMI, and these changes were significantly greater in the test group. WC and visceral fat area (VFA) significantly decreased in both groups (VFA: -10.7 cm² in the test group; -6.8 cm² in the placebo group). These changes did not differ significantly between the groups. However, a subgroup analysis of participants with VFA ≥100 cm² showed a significant decrease in the test group, and this decrease was significantly greater than in the placebo group.

CONCLUSIONS

The intake of high β-glucan barley led to significant and safe reductions in VFA, body weight, BMI, and WC in individuals with visceral fat obesity with VFA ≥100 cm². Barley high in β-glucan may contribute to preventing visceral fat obesity.

Involvement of epithelial-mesenchymal transition in methotrexate-induced pulmonary fibrosis

Epithelial-mesenchymal transition (EMT) plays a pivotal event in the development of pulmonary fibrosis. We have previously reported that methotrexate (MTX)-induced alveolar epithelial cell injury followed by pulmonary fibrosis as a result of the recruitment and proliferation of myofibroblasts. However, there is no data concerning whether EMT occurs in MTX-induced pulmonary fibrosis. In the present study, therefore, we investigated the expression of EMT markers such as E-cadherin, α-SMA, and vimentin by immunofluorescence analysis in mouse lung tissues after administration of MTX. We found that vimentin and α-SMA-positive cells of the MTX-induced pulmonary fibrosis were increased; on the other hand, E-cadherin was decreased, indicating that epithelial cells act as the main source of mesenchymal expansion. These results exhibited the down-regulation of E-cadherin expression and the up-regulation of α-smooth muscle actin (α-SMA) in primary mouse alveolar epithelial cells (MAECs) and A549 cell lines. Additionally, MTX-induced A549 cells exhibited an EMT-like phenotype accompanied by the elevation of the expression of interleukin-6 (IL-6) and transforming growth factor (TGF)-β1, as well as an enhancement of migration. All of these findings suggest that MTX-induced pulmonary fibrosis occurs via EMT.

Genetic polymorphism of the human organic solute carrier protein 1 (hOSCP1) gene in Japanese patients with non-viral liver carcinoma

Human organic solute carrier protein 1 (hOSCP1) is a Na⁺-independent multispecific organic solute transporter. To date, several studies have revealed that gene mutations of the transporters are likely to be associated with some diseases; however, there are no data concerning the genetic polymorphism of the hOSCP1 gene in Japanese patients with non-viral liver carcinoma (LC). In the present study, we isolated genomic DNA from a normal portion of LC, and analyzed 41 single nucleotide polymorphisms (SNPs) chosen from a database of SNPs (dbSNPs). We found genotype frequencies for 2 non-synonymous SNPs [rs34409118 (Thr¹³¹ → Ala) and rs1416840 (Ile²¹⁹ → Thr)] and 1 synonymous SNP [rs16822954 (Ser¹⁹³ → Ser)] to be statistically significant when compared with dbSNPs. No statistical significance was observed in rs2275477 (Gly³⁰⁷ → Arg) in the hOSCP1 gene. With respect to the allele frequency, we also observed rs34409118 to be statistically significant. Interestingly, we found that non-viral LC patients do not carry heterozygous mutations in rs1416840 (A/G) and rs16822954 (A/G), suggesting that a non-carrier of heterozygous mutations in these two SNPs might be a biomarker for susceptibility for non-viral LC in Japanese. Further analyses of patients with hOSCP1 variants may elucidate the relationship between the hOSCP1 gene and susceptibility of non-viral LC in Japanese patients.

Gene polymorphism and frequencies of the NPC1L1 gene (rs2072183, rs217434 and rs217428) in Japanese patients with dyslipidemia

WHAT IS KNOWN AND OBJECTIVE

Niemann-Pick C1-Like 1 (NPC1L1) plays a pivotal role in intestinal cholesterol absorption. Ezetimibe is known as an inhibitor for NPC1L1 and decreases concentration of low-density lipoprotein cholesterol (LDL-C) in blood. Responses of the decrease of serum LDL-C levels to ezetimibe have been reported to be different among NPC1L1 variants. However, there are still limited data concerning the genetic variation in the NPC1L1 gene, specifically, in Japanese patients with dyslipidemia. The purpose of this study is to elucidate genotype and allele frequencies of the NPC1L1 gene in Japanese patients with dyslipidemia.

METHODS

Written informed consent was obtained from all participants. All patients were administered ezetimibe at the dose of 10 mg for once a day either alone or coadministered with statins. Patient's data were retrospectively obtained from their medical records. Genomic DNA was extracted from whole blood samples and analysed three NPC1L1 SNPs (rs2072183, rs217428 and rs217434) by the direct sequencing method.

RESULTS AND DISCUSSION

We found that there is a significant difference of genotype frequencies between healthy Japanese and dyslipidemic subjects in rs2072183. No significant differences were observed in rs217428 and rs217434; however, comparison of our data with literature reports suggests that there are significant differences in the frequencies of rs217428 and rs217434 between Canadian and Japanese dyslipidemic patients.

WHAT IS NEW AND CONCLUSION

Our study is the first report concerning the genotype and allele frequencies of the gene coding for NPC1L1 in Japanese patients with dyslipidemia. The most notable result was to demonstrate that there exists a significant difference in rs2072183 variant between healthy Japanese and dyslipidemic subjects and also found that there exists genetic variation of rs2072183 between Japanese and Canadian patients with dyslipidemia. Our results are expected to facilitate research in the proper use of ezetimibe-based mono- or combination therapies. Further studies will be required to evaluate the effects of rs2072183 on the efficacy of LDL cholesterol reduction by ezetimibe.

Hordatine A β-D-glucopyranoside from ungerminated barley grains

Hordatine A β-D-glucopyranoside was isolated from ungerminated barley grains for the first time and identified by MS spectrometry and one- and two-dimensional NMR spectroscopy. This compound was observed 20 days after flowering (DAF) and most abundant at 35 DAF when the dry weight of grains reached a maximum. The contents of the compound markedly decreased when grains were pearled from 85% to 70% yield, suggesting that the compound is localized in the aleurone layer. The compound was commonly observed in ungerminated mature grains among 10 cultivars, and its contents ranged from 103 to 254 nmol/g dry weight. Because hordatines have been reported to have antifungal activities, the compound may act as an antifungal component in the latter half of the maturing stages and in mature barley grains.

Functional characterization and substrate specificity of a novel gene encoding zinc finger-like protein, ZfLp, in Xenopus laevis oocytes

In the present study, we isolated and determined the pharmacological characteristics of a novel gene encoding the zinc finger-like protein (ZfLp). The isolated cDNA consisted of 1,581 base pairs that encoded a 526-amino acid protein. The amino acid sequence of ZfLp is 96% identical to that of zinc finger protein 415 isoform 5 (ZNF415-5). Reverse-transcription (RT)-polymerase chain reaction (PCR) analysis revealed that the ZfLp mRNA is expressed in the breast, lung, stomach, small intestine colon and ovary, but not in the liver. When expressed in Xenopus laevis oocytes, ZfLp mediated the high affinity transport of [(3)H]paclitaxel (taxol) in a sodium-independent manner (K(m) = 336.7 ± 190.0 nM). The uptake of [(3)H]paclitaxel (taxol) by ZfLp was trans-stimulated by glutarate and glutathione (GSH). A cis-inhibition experiment revealed that ZfLp-mediated transport of [(3)H]paclitaxel (taxol) is inhibited by several organic solutes specifically clotrimazole. Using several clotrimazole derivatives, we found that N-benzylimidazole would be a minimum unit for producing the inhibition of ZfLp-mediated drug uptake. Our results may provide insights into the novel role of soluble protein, such as ZNF, in the human body. Our results, therefore, would be expected to facilitate research on the novel role of ZNFs and on the discovery of novel drugs for targeting ZNF-related proteins such as ZfLp.

[Molecular cloning and functional characterization of a novel gene encoding human prostaglandin carrier, hPrC]

In the present study, we isolated and determined the pharmacological characteristics of a novel gene encoding the human prostaglandin carrier (hPrC). The isolated cDNA consisted of 1431 base pairs that encoded a 477-amino acid protein, and we found that isolated hPrC does not belong to any drug transporter families. RT-PCR analysis revealed that the hPrC mRNA is expressed in various human tissues ubiquitously. When expressed in Xenopus laevis oocytes, hPrC mediated the transport of [(3)H]prostaglandin E(2) (PGE(2)) in a sodium-independent manner. The uptake of [(3)H] PGE(2) was not trans-stimulated by PG analogous. Although there are several PG transporters such as multidrug resistance-associated protein 4 (MRP4), organic cation transporter 1 (OCT1) [solute carrier (SLC) 22A1], organic anion transporter 1-3 (OAT1-3) [SLC22A6-8], OAT4 [SLC11], OATP-1 (LST-1) [SLCO1B1], OATP2B1 [SLCO2B1], OATP2A1 (PGT) [SLCO2A1], OATP4A1 (OATP-E) [SLCO4A1] have been isolated and well characterized, our findings suggest that hPrC functions as a novel transport peptide responsible for PG uptake. Our results should provide insight into the novel mechanism of the PG transport in the human body.

Ribosomal protein L3 mediated the transport of digoxin in Xenopus laevis oocyte

Ribosomal protein L3 (RPL3) is known to be an indispensable and essential component for the peptidyltransferase center. In the present study, we found a novel function of RPL3 using a Xenopus laevis oocyte expression system. When expressed in X. oocytes, RPL3 mediated the high affinity transport of [(3)H]digoxin (K(m) = 213.3 ± 46.8 nM) in a time-, concentration-, and sodium-dependent manners. The maximum velocity of the transport of [(3)H]digoxin via RPL3 produced at physiological pH. However, we did not observe RPL3-mediated transport of several organic solutes such as [(14)C]androstenedione, [(3)H]dexamethasone, [(3)H]dehydroepiandrosterone sulfate, [(3)H]L-tryptophan, [(14)C]L-ascorbic acid, [(14)C]α-ketoglutarate, [(14)C]glutarate, [(3)H]methotrexate, [(3)H]bumetanide, [(3)H]probenecid, [(14)C]salicylic acid, [(14)C]theophylline and [(3)H]valproate. Our results suggest that RPL3 functions as a drug carrier protein and may be involved in the digoxin toxicity in the human body.

Induction of pulmonary fibrosis by methotrexate treatment in mice lung in vivo and in vitro

Methotrexate (MTX) has been used as the first-line disease-modifying antirheumatic drug (DMARD) in patients with early progressive rheumatoid arthritis (RA). Several severe side effects such as myelosuppression, hepato-, nephro-, and pulmonary toxicities have been reported. However, the pathogenic mechanism of MTX-induced pulmonary fibrosis is still unknown. Here, we evaluated the morphological and biological changes of the pulmonary fibrosis in mice treated with MTX. Three, four and five weeks after consecutive administration of MTX (3 mg/kg/day), hydroxyproline content in the lung tissues increased significantly to about 2 times higher that of the control level. This result closely reflected to the results of hematoxylin and eosin (HE) and Azan stains. Immunohistochemical analysis revealed that MTX treatment resulted in a decrease of alveolar epithelial cells and an increase of fibroblast cells in the mouse lung tissues. When we examined the effects of MTX on primary mouse alveolar epithelial cell (MAEC) and mouse lung fibroblast (MLF) survival in vitro, the efficiency of MTX-induced cytotoxicity and apoptosis in MAEC was more sensitive than MLF cells. Thus, our results indicate that the administration of MTX by an oral route could induce a fibrotic response with cell dysfunction of the alveolar epithelium by which MTX-induced apoptosis. Our results thus suggest that MTX could induce alveolar epithelial cell injury and resulted in the loss of integrity of the alveolar-capillary barrier basement membranes followed by the recruitment and proliferation of myofibroblasts with the deposition of collagens.

Effects of phenolic compounds on the browning of cooked barley

Barley grain products undergo browning when cooked. To evaluate effects of phenolic compounds on browning, various amounts of (+)-catechin, proanthocyanidins, or related phenolic compounds were added to aqueous barley extracts or barley pastes, which were heated at 90 degrees C for 1 or 2 h, respectively. In barley extract, (+)-catechin, procyanidin B3 (PCB3), prodelphinidin B3 (PDB3), and a trimer of gallocatechin-gallocatechin-catechin (PDT1) dose-dependently elevated absorbance at 420 nm after heating. PDB3 caused browning faster than PCB3 and (+)-catechin. In barley paste, PDB3 and PDT1 decreased the L* value and increased the a* and b* values of the paste dose-dependently after heating and PCB3 and (+)-catechin did so to a lesser extent. Caffeic acid promoted the browning in both of the extract and paste, while protocatechuic acid, eriodictyol, and (+)-taxifolin promoted it in the extract and myricetin and quercetin promoted it in the paste. Compounds promoting browning have catechol or pyrogallol structures in common.

Effect of interleukins response to ECM-induced acquisition of drug resistance in MCF-7 cells

AIM

To examine the effect of various components of extracellular matrix (ECM) on acquisition of drug resistance to taxol and camptothecin by breast carcinoma cell line MCF-7.

METHODS

Cancer cells were cultured on bovine serum albumin (BSA), vitronectin (VN), fibronectin (FN), collagen type I (COL-I), or Matrigel-coated plates with or without taxol (paclitaxel) or camptothecin treatment. The effect of anticancer drugs on cell growth was accessed by XTT assay, and the alterations of cellular morphology were examined by phase contrast microscopy. Immunofluorescence study was performed using monoclonal anti-beta-tubulin antibody.

RESULTS

All cell lines showed a significant decrease in cell survival when treated with anticancer drugs without components of ECM, whereas survival rates of Caco-2, MCF-7 and NCI-H292 were significantly increased when cells were cultured on COL-I- and Matrigel-coated dishes after treatment with paclitaxel or camptothecin. MCF-7 cells showed and maintained a colony formation when cultured on the COL-I- and Matrigel-coated dish. Moreover, cytotoxicity (IC50) was decreased by taxol (paclitaxel) or camptothecin treatment during colony formation in MCF-7 cells, suggesting that morphological changes could increase survival of cells treated with anticancer drugs. Thick circumferential bundles of microtubules around the periphery of the cells and chromatin condensation was not observed for MCF-7 cells on COL-I- and Matrigel-coated dishes treated with paclitaxel. To confirm this, spheroid cells were prepared, and we found that cytotoxicity was decreased for these cells, and significantly increased when cells were co-cultured on Matrigel- or COL-I-coated upper wells. The effect of anticancer drugs on cell survival was efficiently inhibited by interleukin-6 (IL-6) and interleukin-8 (IL-8).

CONCLUSIONS

Present results suggested that not only integrin-ECM interactions but also other factors such as IL-6and IL-8secreted by cancer cells, cultured on COL-I and Matrigel dishes, are involved in the acquisition of drug resistance by MCF-7.

Changes in anthocyanins in the grains of purple waxy hull-less barley during seed maturation and after harvest

Purple waxy hull-less barley cv. Daishimochi accumulates purple pigments in the stem, awn, lemma, palea, and pericarp during seed maturation. Four major anthocyanin constituents from the grains of cv. Daishimochi were isolated and identified as cyanidin 3-O-(3,6-di-O-malonyl-beta-D-glucopyranoside) (55%), cyanidin 3-O-(6-O-malonyl-beta-D-glucopyranoside) (21%), cyanidin 3-O-(3-O-malonyl-beta-D-glucopyranoside) (12%), and cyanidin 3-O-beta- d-glucopyranoside (4%) by mass spectrometry and one- and two-dimensional NMR spectroscopy. These anthocyanins were observed after 28 days after flowering (DAF); they were most abundant at 35 DAF when the dry weight of grains was maximum. This accumulation time was later than that of proanthocyanidins, which are the most abundant polyphenol constituents in barley grains. These anthocyanins, especially cyanidin 3-O-(3,6-di-O-malonyl-beta- d-glucopyranoside), decreased at 42 DAF and during drying preparation after harvest. Most anthocyanins are localized in the outer parts of grains and distributed into bran by the pearling process. Whole grain flour and bran of cv. Daishimochi are good sources of malonylated cyanidin derivatives.

Rat organic solute carrier protein 1 (rOscp1) mediated the transport of organic solutes in Xenopus laevis oocytes: isolation and pharmacological characterization of rOscp1

Rat organic solute carrier protein 1 (rOscp1) was isolated from a rat testis cDNA library. Isolated rOscp1 cDNA consisted of 1089 base pairs that encoded a 363-amino acid protein, and the amino acid sequence was 88% and 93% identical to that of human OSCP1 (hOSCP1) and mouse Oscp1 (mOscp1), respectively. The message for rOscp1 is highly detected in rat testis. When expressed in X. oocytes, rOscp1 mediated the high affinity transport of p-aminohippurate (PAH) with a Km value of 15.7+/-1.9 microM, and rOscp1-mediated organic solutes were exhibited in time- and Na+-independent manners. rOscp1 also transported various structurally heterogenous compounds such as testosterone, dehydroepiandrosterone sulfate (DHEA-S), and taurocholate with some differences in substrate specificity compared with hOSCP1. Immunohistochemical analysis revealed that the rOscp1 protein is localized in the basal membrane side of Sertoli cells as observed in mouse testis [Kobayashi et al., 2007; Kobayashi, Y., Tsuchiya, A., Hayashi, T., Kohyama, N., Ohbayashi, M., Yamamoto, T., 2007. Isolation and characterization of polyspecific mouse organic solute carrier protein 1 (mOscp1). Drug Metabolism and Disposition 35 (7), 1239-1245]. Thus, the present results indicate that a newly isolated cDNA clone, rOscp1, is a polyspecific organic solute carrier protein with some differences in substrate specificity compared with human and mouse OSCP1.

Effects of Various Methoxyflavones on Vincristine Uptake and Multidrug Resistance to Vincristine in P-gp-Overexpressing K562/ADM Cells

PURPOSE

Some methoxyflavones (MFs) are known to inhibit the function of P-glycoprotein. The aim of this study is to characterize the reversal of multidrug resistance (MDR) by MFs.

METHODS

The effects of 19 MFs, including 3,5,6,7,8,3',4'-heptamethoxyflavone, nobiletin, and tangeretin, and flavone on the uptake of [3H]vincristine into an adriamycin-resistant variant of human chronic myelogenous leukemia (K562/ADM) cells were investigated. Potentiation of vincristine-induced growth inhibition by these MFs was also tested in K562/ADM cells by means of WST-1 [2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium] assay.

RESULTS

All MFs (20 microM) tested increased the uptake of [3H]vincristine. 3,5,6,7,8,3',4'-heptamethoxyflavone, nobiletin, tangeretin, quercetagetin and quercetin pentamethylether showed especially potent effects. The increase in the uptake of [3H]vincristine was proportional to the number of methoxyl moieties. While substitution with a methoxyl moiety at the C3 position was the most influential, methoxyl substitution at both the C3' and C5' positions resulted in a decrease in the potentiation of uptake. Furthermore, there was a significant correlation between the potencies for increasing [3H]vincristine uptake and for growth inhibition assessed by WST-1 assay.

CONCLUSIONS

MFs increased the uptake of [3H]vincristine into MDR cells and exhibited MDR-reversing effects. Their potencies were influenced by the number and positions of the methoxyl moieties.

Isolation and characterization of polyspecific mouse organic solute carrier protein 1 (mOscp1)

We succeeded in isolating the cDNA-encoding mouse organic solute carrier protein 1 (mOscp1) from a mouse testis cDNA library. mOscp1 consisted of 1137 base pairs that encoded a 379-amino acid protein, and the amino acid sequence was 85% identical to that of human OSCP1 (hOSCP1). Northern blot analysis revealed that the gene coding for mOscp1 is highly expressed in the testis, but not in other tissues. When expressed in Xenopus laevis oocytes, mOscp1 mediated the high-affinity transport of p-aminohippurate (PAH) (K(m) = 18.8 +/- 4.1 microM) with Na(+) independence. mOscp1 transported various kinds of structurally dissimilar drugs and chemicals such as probenecid, dehydroepiandrosterone sulfate, and glutarate with some differences in substrate specificity compared with hOSCP1. Cyclophosphamide inhibited the mOscp1-mediated PAH uptake. Immunohistochemical analysis revealed that the mOscp1 protein is localized in the plasma membrane side of Sertoli cells in the testis. Our results indicate that isolated mOscp1 is a polyspecific organic solute carrier protein and may be a key molecule for the testicular handling of organic solutes.

Mouse organic anion transporter 2 and 3 (mOAT2/3[Slc22a7/8]) mediates the renal transport of bumetanide

Multispecific organic anion transporters play an important role in the excretion and the elimination of a wide variety of endogenous and exogenous substrates. To date, five murine OAT homologs such as mouse organic anion transporters 1-3, 5, and 6 (mOAT1-3, 5 and 6) have been isolated and well characterized. With the exception of mOAT6, other mOAT isoforms are predominantly expressed in the kidney. The aim of this study was to examine whether mOAT2/3, as well as hOAT2/3, transports the diuretic bumetanide using a Xenopus laevis oocyte expression system. When expressed in Xenopus oocytes, mOAT2/3 mediated the high affinity transport of bumetanide. The apparent K(m) values for the uptake of bumetanide via mOAT2 and mOAT3 were 9.12 +/- 2.42 microM and 1.01 +/- 0.27 microM, respectively. Immunohistochemical analysis revealed that mOAT2 is expressed on the luminal membrane site of the proximal tubule. Our results indicate that mOAT2 and 3, as well as human homologs, are molecules for the transport of bumetanide on the luminal membranes of kidney proximal tubules.

Functional characterization of human monocarboxylate transporter 6 (SLC16A5)

Human monocarboxylate transporter 6 (MCT6) has recently been isolated, and its tissue distribution has been established at the mRNA level, but its functional properties remain unknown. The aim of this study is to investigate the transport properties of MCT6. When expressed in Xenopus laevis oocytes, MCT6 transported [3H]bumetanide in a pH- and membrane potential-sensitive but not proton gradient-dependent manner, with the K(t) value of 84 microM. Furthermore, MCT6 transported various drugs such as probenecid and nateglinide. Neither [14C]L-lactic acid nor [3H]L-tryptophan, typical substrates of other MCT isoforms, was transported by MCT6. Four loop diuretics, i.e., furosemide, piretanide, azosemide, and torasemide, thiazides, probenecid, glibenclamide, and nateglinide inhibited the MCT6-mediated uptake of [3H]bumetanide. In contrast, short-chain carboxylic acids, such as L-lactic acid and succinic acid did not inhibit the MCT6-mediated uptake of bumetanide. These results suggest that the substrate specificity of MCT6 is distinct from those of other MCTs. Bumetanide would be a good tool for investigating the functional properties of MCT6. It is probable that MCT6 is involved in the disposition of various drugs, including bumetanide.

Dendriform pulmonary ossification in patient with rare earth pneumoconiosis

The case history is presented of a patient with pathologically proven dendriform pulmonary ossification and rare earth pneumoconiosis confirmed by analytical transmission electron microscopy. This is thought to be the first report of this association.

Isolation and Functional Characterization of a Novel Organic Solute Carrier Protein, hOSCP1

We succeeded in isolating a novel organic solute carrier from a human placenta cDNA library. The isolated cDNA consisted of 1137 base pairs that encoded a 379-amino acid protein, hOSCP1. Northern blot and reverse transcription PCR analyses revealed that the hOSCP1 mRNA is expressed in the placenta and testis and weakly expressed in the thymus and small intestine. When expressed in Xenopus laevis oocytes, hOSCP1 mediated the high affinity transport of p-aminohippurate (PAH) (K(m) = 35.0 +/- 7.5 microm) and tetraethylammonium (K(m) = 62.3 +/- 12.2 microm) in a sodium-independent manner. However, the hOSCP1-expressing oocyte did not mediate the transport of L-carnitine. The transport of PAH by hOSCP1 was sensitive to pH, but the tetraethylammonium was not transported at the high pH examined. hOSCP1 transported prostaglandin E(2), prostaglandin F(2alpha), estrone sulfate, glutarate, L-leucine, L-ascorbic acid, and tetracycline. Thus, hOSCP1 also showed broad substrate specificity. A wide range of structurally unrelated organic compounds inhibited the hOSCP1-mediated PAH uptake. Immunohistochemical analysis revealed that the hOSCP1 protein is localized in the basal membrane of the syncytiotrophoblast in the human placenta. Our results suggest that hOSCP1 is a novel polyspecific organic solute carrier protein responsible for drug clearance from the human placenta.

Transport mechanism and substrate specificity of human organic anion transporter 2 (hOat2 [SLC22A7])

Human organic anion transporter 2 (hOat2[SLC22A7]) is highly expressed in the human liver. Although localization, gene expression, substrate specificity and transport mechanisms of other human Oat isoforms such as human Oat1 (hOat1), human Oat3 (hOat3) and human Oat4 (hOat4) have been elucidated, information concerning human Oat2 (hOat2) is less defined. The objective of this study was to provide further information on the transport mechanism and substrate specificity of hOat2. When expressed in Xenopus laevis oocytes, the transport of organic compounds mediated by hOat2 was not affected by the replacement of extracellular sodium with lithium, choline and mannitol. The uptake of estrone sulfate (ES) in hOat2-expressing oocytes was significantly trans-stimulated by preloading the oocytes with fumarate and succinate, but not glutarate. Moreover, we observed that hOat2 mediates the transport of bumetanide, ES, glutarate, dehydroepiandrosterone sulfate, allopurinol, prostaglandin E2, 5-fluorouracil, paclitaxel and L-ascorbic acid. These compounds are identified for the first time as hOat2 substrates. A wide range of structurally unrelated organic compounds inhibited the hOat2-mediated uptake of tetracycline, except for sulfobromophthalein. All of these findings indicate that hOat2 is a sodium-independent multi-specific organic anion/dimethyldicarboxylate exchanger. Our present findings thus provide further insights into the role of hOat2 in hepatic drug transport.

Possible involvement of organic anion transporter 2 on the interaction of theophylline with erythromycin in the human liver

Organic anion transporter 2 (Oat2 [SLC22A7]) is a multispecific organic anion transporter. Although several substrates of human Oat2 (hOat2) have been elucidated, a possible involvement of hOat2 in drug interaction is less defined. The purpose of this study was to investigate the interaction of theophylline with erythromycin mediated by hOat2 using a Xenopus laevis oocyte expression system. When expressed in Xenopus oocytes, hOat2 mediated the transport of theophylline and erythromycin. The finding indicates that the two compounds are novel substrates for hOat2. The apparent K(m) values for the uptake of hOat2 that mediated the transport of theophylline and erythromycin were 12.6 muM and 18.5 muM, respectively. The hOat2-mediated uptake of [(14)C]theophylline and [(14)C]erythromycin was cis-inhibited by adding erythromycin and theophylline, respectively. Our present findings suggest that hOat2 may, at least in part, be involved in the theophylline-erythromycin interaction in the human liver.

RENAL TRANSPORT OF ORGANIC COMPOUNDS MEDIATED BY MOUSE ORGANIC ANION TRANSPORTER 3 (MOAT3): FURTHER SUBSTRATE SPECIFICITY OF MOAT3

Organic anion transporter 3 [Oat3(Slc22a8)] plays an important role in the renal handling of organic compounds. The substrate specificity of rat Oat3 and human Oat3 has been elucidated; information on mouse Oat3 (mOat3) is less defined. The aim of this study was to extend the substrate selectivity of mOat3. When expressed in Xenopus laevis oocytes, mOat3 mediated the uptake of p-aminohippuric acid and estron sulfate (ES). In addition to these substrates, we found that several organic compounds such as prostaglandin E(2), prostaglandin F(2alpha), allopurinol, 6-mercaptopurine (6-MP), 5-fluorouracil (5-FU), and l-carnitine are substrates of mOat3, compounds identified for the first time. The apparent K(m) values for the uptake of mOat3 that mediated the transport of 6-MP, 5-FU, and l-carnitine were 4.01 +/- 0.7 microM, 53.9 +/- 8.9 nM, and 61.9 +/- 1.1 nM, respectively. Northern blot analysis revealed that gene coding for mOat3 is predominant in the kidney and, to a lesser extent, in the brain and the eye. Our findings thus provide further insights into the role of Oat3 in renal drug transport.

An operated case of lung cancer with pleural plaques: its asbestos bodies, fiber analysis and asbestos exposure

This case was a 79-year-old man with pleural plaques, which had been pointed out in the left lung field on chest X-ray six years ago. A new shadow in the right chest appeared in 1999 and was closely examined. Cytological class IV carcinoma was detected in his lung tissue obtained by broncho-fiberscope. Lobectomy of the right upper lobe was performed, and calcified pleural plaques were found on the chest wall. The clinical diagnosis was poorly differentiated squamous cell carcinoma, T1N0M0. In World War II when he was 26 years old, he had worked as a boiler man on a battle cruiser for one year. The amount of asbestos bodies (AB) was 3,348 per gram dry lung tissue. The cores of AB and asbestos fibers were examined and showed that amosite was the most prevalent and crocidolite, tremolite and chrysotile were present in that order. After leaving the navy, he had worked as a farmer throughout his life, suggesting that he had never contacted asbestos occupationally after being a boiler man. It is strongly suggested that he had been exposed to asbestos during his work as a boiler man and that produced pleural plaques and lung cancer 50 years' later.

Airborne fiber concentration and size distribution of mineral fibers in area with serpentinite outcrops in Aichi prefecture, Japan

Airborne fiber concentrations and size distributions of both asbestos and nonasbestos fibers were determined at property boundaries of 4 serpentinite quarries producing crushed stone (quarry property boundary), 10 sites within 10 km of the area with serpentinite outcrops (serpentinite area), and 2 sites in a reference area. The asbestos was identified in 7 rock and 3 soil samples collected in the serpentinite area. The geometric means of airborne concentrations of asbestos and nonasbestos fibers longer than 0.2 microm in length were: 384 and 447 fibers/liter (f/L) in the quarry property boundary (in operation), 12 and 124 f/L in the quarry property boundary (in closed), 5 and 103 fibers/liter in the serpentinite area, and less than 2 and 59 fibers/liter in the reference area, respectively. There was a significant difference in airborne concentrations of both asbestos and nonasbestos fibers among the areas. Ttremolite/actinolite were found with chrysotile in the stones. Airborne concentrations of tremolite/actinolite were higher than those of chrysotile at the quarry property boundary and in the serpentinite area. Tremolite/actinolite were also found in the soils. There was no significant difference among the areas in the arithmetic means of fiber size distribution of both asbestos and nonasbestos fibers.

Clinical, pathological and mineralogical features in two autopsy cases of workers exposed to agalmatolite dust

An agalmatolite miner and processor showed large shadows at the bilateral hila accompanied by surrounding emphysematous changes and irregular shadows on chest X-ray films. Chest CT scans were characterized by a mixture of tiny irregular structures and small round opacities. Histopathological examination revealed massive fibrosis, which corresponded to large shadows, but only a small number of typical silicotic nodules, indicating mixed dust pneumoconiosis. Mineralogical examination of the autopsy lungs showed quartz, pyrophyllite, mica, and kaolinite. Quartz accounted for 70% of the amount of all mineral dust in both patients, but pyrophyllite accounted for 10.8% and 14.4%. The pulmonary mineral dust composition in the two patients was well consistent with the mineral composition of the raw clays in the agalmatolite mine. In the two patients, chest X-ray findings and histopathological findings of the lungs also suggested agalmatolite pneumoconiosis, which was confirmed by mineral analysis of the lungs.

Biological effects of man-made mineral fibers (II)--their genetic damages examined by in vitro assay

In order to study and compare genetic damage induced by 10 kinds of man-made mineral fibers (JFM fibers) in cells, human lung epithelial cells (A549) were exposed to JFM fibers and chrysotile for 1 h, then single-cell gel electrophoresis (SCGE) assay was used to detect DNA strand breaks, DNA-DNA interstrand crosslink and the ability of DNA to repair; The results showed that all 10 JFM fibers could induce DNA strand breaks, DNA-DNA interstrand crosslinks and inhibit the ability of DNA repair. When human embryo lung (HEL) cells were exposed to JFM fibers and chrysotile for 24 h respectively, the chromosomal aberration was analyzed and the results showed that chrysotile and most of JFM fibers at 5.0 micrograms/ml induced structural chromosomal aberration, but all of these effects were lower than that of chrysotile and were different among them, suggesting that 10 types of JFM fibers had genotoxicity with different degree in vitro, but all of them were lower than that of chrysotile.

Acute biological effects of intratracheally instilled titanium dioxide whiskers compared with nonfibrous titanium dioxide and amosite in rats

The dimensions of man-made mineral fiber whiskers are similar to those of some kinds of asbestos. Thus these mineral fibers raise the concern for potential health hazard for workers exposed in the occupational environments. This study was designed to define acute biological effects of intratracheally administered titanium dioxide whiskers (TO1) compared with nonfibrous titanium dioxide (TOP) and UICC amosite (Ams), and their relations to acute lung inflammation in rats. The observed geometric mean length (microm) and width (microm) and geometric standard deviation are: TO1(2.1[2.0], 0.14[1. 53]); Ams (4.3[3.3], 0.31[1.9]); and TOP (50 nm, 1-2 microm aggregates). Ten-week-old Wistar-Jcl male rats received a single tracheal injection of test materials at doses between 0.05 and 1.0 mg/rat. Control animals were injected with the same volume of saline. Lung tissue and bronchoalveolar lavage (BAL) fluid were collected from rats on days 1, 3, and 7 after administration. In the group injected with TO1, total protein, cytokine-induced neutrophil chemoattractant (CINC)/growth-regulated gene product (GRO), interleukin (IL) 1beta, and tumor necrosis factor (TNF) alpha increased on day 1. Subsequently, total elastolytic activity and fucose levels in BAL increased by day 3. All parameters, except for fucose in BAL, recovered to the normal levels. Animals in the Ams group showed increased total protein and CINC/GRO and decreased total elastolytic activity in a dose-dependent manner on day 1. The fucose level increased on day 3 in the Ams group. All parameters returned to their control levels on day 7. Animals in the TOP group did not show significant changes any of parameters during the experimental period. Gene expression of TNF-alpha and monocyte chemoattractant protein (MCP) 3 in the lung increased dose-dependently in the animals treated with the three materials. The mRNAs for eotaxin and MIP-1alpha were overexpressed in the lung of animals treated with Ams and TO1, while RANTES mRNA was overexpressed dose-dependently in the lung of animals treated with Ams on day 1. Onset of inflammatory response was more rapid in the Ams group than the TO1 group. Recovery of the fucose level in BAL was slower in the TO1 group than in the Ams group, though we observed similar histopathological changes in the lung of animals with TO1 or Ams. We conclude that whisker-induced acute biological effects in the lung may be related to the shape of the whiskers and not to their chemical composition or surface crystal structure, showing biological effects similar to those of UICC amosite.