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1.
Respir Med Case Rep ; 47: 101974, 2024.
Article in English | MEDLINE | ID: mdl-38374927

ABSTRACT

Lambert-Eaton myasthenic syndrome (LEMS) is a rare disease but is often associated with small-cell lung cancer (SCLC). We discuss the case of a 65-year-old man diagnosed with SCLC-LEMS and treated with carboplatin, etoposide, and durvalumab. Lower extremity weakness and high anti-P/Q voltage-gated calcium channel (VGCC) antibody levels were diagnostic and helpful. The patient showed a reduction in neurological symptoms with treatment for SCLC, including an immune checkpoint inhibitor (ICI), without standard treatment for LEMS. This treatment may be a treatment option, although the recurrence of LEMS as an immune-related adverse events (irAEs) should be noted.

2.
Drug Discov Ther ; 17(6): 404-408, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-38143076

ABSTRACT

The effects of acute intratracheal administration of electrolyzed reduced water (ERW; alkaline electrolyzed water) were investigated in rats. In this study, no deaths or near-deaths were recorded in either group, namely those treated with ERW or purified water (maximum doses of 900 mg/kg). The main symptoms observed in the rats were decreased spontaneous movements and abnormal breath sounds, which were considered to be transient symptoms caused by intratracheal administration. In addition, low values of alkaline phosphatase, total protein and lactate dehydrogenase were found in BALF tests, but these values were considered to be of low toxicological significance, since they are usually high in the presence of lung inflammation or cellular damage. This suggests that the alkalinity of ERW partially contributes to broken peptide bonds in proteins. There were no significant increases in bronchoalveolar lavage fluid protein in either group. ERW did not cause an increase in the influx of neutrophils, eosinophils, basophils, or lymphocytes, suggesting that intratracheal administration of ERW did not cause lung inflammation. ERW did not cause abnormalities in the body or pathological changes in the lungs. Aggregates of alveolar macrophages, as a measure of inflammation, were observed in both groups. These may be transient symptoms due to intratracheal administration, not due to ERW toxicity. This study confirmed the safety of intratracheal ERW infusion and demonstrated the low risk of acute toxicity for inhalation exposure to ERW aerosol or vapor. Therefore, ERW may be an effective air purifier against viruses or bacteria.


Subject(s)
Pneumonia , Water , Rats , Animals , Water/pharmacology , Lung , Bronchoalveolar Lavage Fluid , Administration, Inhalation
3.
Thorac Cancer ; 14(34): 3415-3418, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37837329

ABSTRACT

Lung carcinosarcoma is acknowledged as a rare form of lung cancer. Due to its rarity, the inability to conduct large-scale clinical trials and interventions is currently carried out based on empirical evidence. In this study, we report the case of a 73-year-old female patient diagnosed with postoperative recurrence of lung carcinosarcoma. The resected tumor was diagnosed as lung carcinosarcoma, and genetic testing revealed the presence of the epidermal growth factor receptor (EGFR) exon21 L858R. Approximately 2 years postoperatively, the tumor recurred and the patient was treated with erlotinib plus ramucirumab, which were effective in controlling metastatic disease. Erlotinib plus ramucirumab is therefore a treatment option for EGFR mutation-positive lung carcinosarcoma.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Aged , Female , Humans , Carcinoma, Non-Small-Cell Lung/pathology , ErbB Receptors/genetics , Erlotinib Hydrochloride/pharmacology , Erlotinib Hydrochloride/therapeutic use , Lung/pathology , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Mutation , Protein Kinase Inhibitors/therapeutic use , Ramucirumab
4.
J Appl Toxicol ; 43(5): 649-661, 2023 05.
Article in English | MEDLINE | ID: mdl-36317230

ABSTRACT

Crystalline silica is an important cause of serious pulmonary diseases, and its toxic potential is known to be associated with its surface electrical properties. However, in vivo data clarifying the relevance of silica's toxic potential, especially its long-term effects, remain insufficient. To investigate the contribution of physico-chemical property including surface potential on the hazard of nanocrystalline silica, we performed single intratracheal instillation testing using five different crystalline silicas in a rat model and assessed time-course changes in pulmonary inflammation, lung burden, and thoracic lymph node loads. Silica-nanoparticles were prepared from two commercial products (Min-U-Sil5 [MS5] and SIO07PB [SPB]) using three different pretreatments: centrifugation (C), grinding (G), and surface dissolving (D). The five types of silica particles-MS5, MS5_C, SPB_C, SPB_G, and SPB_D-were intratracheally instilled into male F344 rats at doses of 0 mg/kg (purified water), 0.22 mg/kg (SPB), and 0.67, 2, or 6 mg/kg (MS5). Bronchoalveolar lavage, a lung burden analysis, and histopathological examination were performed at 3, 28, and 91 days after instillation. Granuloma formation was present in MS5 group at 91 days after instillation, although granuloma formation was suppressed in MS5_C group, which had a smaller particle size. SPB_C induced severe and progressive inflammation and kinetic lung overload, whereas SPB_G and SPB_D induced only slight and transient acute inflammation. Our results support that in vivo toxic potential of nanosilica by intratracheal instillation may involve with surface electrical properties leading to prolonged effect and may not be dependent not only on surface properties but also on other physico-chemical properties.


Subject(s)
Pneumonia , Silicon Dioxide , Rats , Male , Animals , Rats, Inbred F344 , Silicon Dioxide/adverse effects , Bronchoalveolar Lavage Fluid/chemistry , Lung , Pneumonia/chemically induced , Pneumonia/pathology , Inflammation/chemically induced , Inflammation/pathology , Granuloma/pathology , Intubation, Intratracheal
5.
J Toxicol Pathol ; 34(1): 43-55, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33627944

ABSTRACT

Occupational exposure to nickel oxide (NiO) is an important cause of respiratory tract cancer. Toxicity is known to be associated with the dissociated component, i.e. nickel (II) ions. To address the relationship between physicochemical properties, including solubility in artificial lysosomal fluid, of NiO and time-course changes in the pulmonary response, we conducted an intratracheal instillation study in male Fischer rats using four different well-characterized NiO products, US3352 (NiO A), NovaWireNi01 (NiO B), I small particle (NiO C), and 637130 (NiO D). The NiOs were suspended in purified water and instilled once intratracheally into male F344 rats (12 weeks old) at 0 (vehicle control), 0.67, 2, and 6 mg/kg body weight. The animals were euthanized on days 3, 28, or 91 after instillation, and blood analysis, bronchoalveolar lavage fluid (BALF) testing, and histopathological examination were performed. The most soluble product, NiO B, caused the most severe systemic toxicity, leading to a high mortality rate, but the response was transient and surviving animals recovered. The second-most-soluble material, NiO D, and the third, NiO A, caused evident pulmonary inflammation, and the responses persisted for at least 91 days with collagen proliferation. In contrast, NiO C induced barely detectable inflammation in the BALF examination, and no marked changes were noted on histopathology. These results indicate that the early phase toxic potential of NiO products, but not the persistence of pulmonary inflammation, is associated with their solubility.

6.
Gan To Kagaku Ryoho ; 47(10): 1443-1447, 2020 Oct.
Article in Japanese | MEDLINE | ID: mdl-33130738

ABSTRACT

OBJECTIVE: To retrospectively assess data on immune checkpoint inhibitors(ICIs)in an actual clinical setting, examine the factors that contribute to response and survival using real-world data, and compare the effectiveness of the 3 types of ICIs for patients with non-small cell lung cancer(NSCLC). METHODS: A retrospective analysis of 127 patients with NSCLC treated with ICIs at our hospital was conducted. RESULTS: Nivolumab(56 patients)showed a 3-year survival rate of 21.6% and a disease control rate of 57.1%. These results are consistent with the clinical trials of Nivolumab. Pembrolizumab(36 patients) showed a 2-year survival rate of 60.3%, a response rate of 50.0%, and a disease control rate of 63.9%. Atezolizumab(35 patients)displayed a particularly low response rate with a 1-year survival rate of 58.4%, response rate of 8.6%, and disease control rate of 25.7%. The treatment results for recurrence after surgery for lung cancer were comparable to those for unresectable lung cancer. CONCLUSION: Anti-PD-1 antibody displayed better therapeutic results than anti-PD-L1 antibody. The efficacy of ICI administration for postoperative recurrent lung cancer was also shown in this study.


Subject(s)
Antineoplastic Agents, Immunological , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Antineoplastic Agents, Immunological/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Humans , Lung Neoplasms/drug therapy , Neoplasm Recurrence, Local , Retrospective Studies , Treatment Outcome
7.
Kyobu Geka ; 73(7): 543-546, 2020 Jul.
Article in Japanese | MEDLINE | ID: mdl-32641675

ABSTRACT

A 26-year-old man was admitted to our hospital for an examination of a mediastinal tumor. Chest computed tomography(CT) showed a giant anterior mediastinal tumor narrowing the trachea and right main bronchus. Although needle biopsy could not be done because of patient respiratory condition, non-seminomatous mediastinal germ cell malignant tumor was strongly suspected by high level of serum AFP without no abnormal finding in his testis. After 1 cycle of chemotherapy by cisplatin, etoposide and bleomycin, the mediastinal tumor decreased in size. Percutaneous biopsy was challenged, however, definite diagnosis could not be established and the surgical resection was performed. The tumor was pathologically diagnosed as mature teratoma with elements of a yolk-sac tumor and some sort of sarcoma. Sudden onset of back pain and thrombocytopenia were encountered 5 months after the operation. Hematologic examination confirmed acute megakaryoblastic leukemia, and remission-induction therapy and allogeneic hematopoietic stem cell transplantation were performed. Twelve months after the operation, the patient is well without recurrence of either disease.


Subject(s)
Leukemia, Megakaryoblastic, Acute , Mediastinal Neoplasms/drug therapy , Neoplasms, Germ Cell and Embryonal , Adult , Antineoplastic Combined Chemotherapy Protocols , Child , Etoposide/therapeutic use , Humans , Male
8.
J Occup Health ; 62(1): e12117, 2020 Jan.
Article in English | MEDLINE | ID: mdl-32515878

ABSTRACT

OBJECTIVE: In this study, in order to investigate the usefulness of intratracheal instillation in assessing the pulmonary toxicity of nanomaterials, intratracheal instillation of nickel oxide-nanoparticles (NiO-NP) was performed. METHODS: In this study, rats were administered test materials by intratracheal instillation at five different research institutions in order to assess the validity of using intratracheal instillation for hazard identification of nanomaterials. Eight-week-old male SD rats were administered NiO-NP dispersed in deionized water by a single intratracheal instillation at doses of 0 (vehicle control), 0.2, 0.67, and 2 mg/kg BW. Three days after instillation, histopathological examination of the lungs was performed. RESULTS: NiO-NP was distributed in the vicinity of hilus of the lung and in the alveoli around the bronchioles. Histopathological changes such as degeneration/necrosis of macrophages, inflammation, and proliferation of type II pneumocyte in the lung were observed, and their severity corresponded with increasing dose. The histopathological observations of pulmonary toxicity were almost similar at each institution. CONCLUSION: The similarity of the histopathological changes observed by five independent groups indicates that intratracheal instillation can be a useful screening method to detect the pulmonary toxicity of nanomaterials.


Subject(s)
Inhalation Exposure/adverse effects , Lung Diseases/chemically induced , Metal Nanoparticles/toxicity , Nickel/toxicity , Animals , Male , Rats , Rats, Sprague-Dawley
9.
Kyobu Geka ; 73(1): 63-67, 2020 Jan.
Article in Japanese | MEDLINE | ID: mdl-31956251

ABSTRACT

We experienced 3 cases in whom multidisciplinary treatment with pericardial fenestration was effective for malignant pericardial effusion associated with lung cancer. Case 1:Right upper lobectomy for lung adenocarcinoma, EGFR (-) and ALK (-) had been performed. After 34 months, malignant pericarditis occurred and left pericardial fenestration was performed. After fenestration, anticancer drugs and immune checkpoint inhibitor( ICI) were administered. He died of lung cancer in 53 months after fenestration. Case 2:Thirty-three months after left upper lobectomy for lung adenocarcinoma [EGFR (+) and ALK (-)], malignant pleuritis and pericarditis occurred and right pericardial fenestration was performed. After fenestration, anticancer drugs, EGFR-TKI and ICI were administered. He died of lung cancer in 35 months after fenestration. Case 3:Pericardial fenestration was performed for malignant pericarditis due to lung adenocarcinoma with EGFR (-), ALK (-) and PD-L1 [tumor propotion score (TPS) 0%]. After fenestration, anticancer drugs and ICI were administered. The patient died of lung cancer in 15 months after fenestration. Pericardial fenestration for malignant pericarditis is possibly useful for the management of patients, which in turns is also useful in continuing the medical treatment to prolong the prognosis.


Subject(s)
Heart Neoplasms , Lung Neoplasms , Pericarditis , Pleural Neoplasms , Humans , Male , Prognosis
10.
Kyobu Geka ; 72(13): 1053-1056, 2019 Dec.
Article in Japanese | MEDLINE | ID: mdl-31879378

ABSTRACT

We assessed the relation between smoking and pneumothorax in patients aged <40. Of 526 patients who underwent surgery for pneumothorax in 2011~2015, 311 were under the age of 40 and they were included in this study. Of 311, 54 cases( 17.4%) were diagnosed with spontaneous pneumothorax associated with emphysematous change by pathological assessment. By the multivariate analysis, 2 parameters exhibited significance for the risk of these spontaneous pneumothorax:a Brinkmann index of ≥165 and a smoking period of ≥9.5 years. It was suggested that smoking is strongly related to the onset of spontaneous pneumothorax even in the younger population less than 40 years of age.


Subject(s)
Pneumothorax , Adolescent , Adult , Humans , Recurrence , Retrospective Studies , Smoking , Young Adult
11.
Kyobu Geka ; 72(12): 1042-1045, 2019 Nov.
Article in Japanese | MEDLINE | ID: mdl-31701919

ABSTRACT

The patient was a 72-year-old man with a history of bronchiectasis. He was admitted to our hospital for an examination of hoarseness. Chest computed tomography (CT) showed bronchiectasis in the bilateral lungs and bronchial artery aneurysm in the mediastinum. To prevent rupture of the aneurysm, we imaged the bronchial artery aneurysm by selective bronchial artery angiography and performed bronchial artery embolization (BAE) with 19 platinum coils. Three months after successful BAE, his hoarseness had improved, and the bronchial artery aneurysm was reduced in size after 12 months. To our knowledge, this is the 1st report of BAE improving hoarseness due to bronchial artery aneurysm.


Subject(s)
Aneurysm , Bronchial Arteries , Embolization, Therapeutic , Aged , Angiography , Hoarseness , Humans , Male
12.
Mol Clin Oncol ; 9(6): 640-646, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30546894

ABSTRACT

The expression levels of thymidine phosphorylase (TP), dihydropyrimidine dehydrogenase (DPD), thymidylate synthase (TS) and orotate phosphoribosyltransferase (OPRT) may predict the clinical efficacy of 5-fluorouracil-based chemotherapy in patients with cancer. We herein investigated the differences in the mRNA levels of these enzymes in non-small-cell lung cancer (NSCLC) and evaluated their prognostic value for NSCLC treated by surgical resection. The intratumoral mRNA levels of TP, DPD, TS, and OPRT were quantified in 66 patients with pathological stage I and II NSCLC (adenocarcinoma or squamous cell carcinoma) following complete resection according to the Danenberg Tumor Profile method. The TP level was the only significant prognostic factor for disease-specific survival (DSS) following complete resection; the mean TP mRNA level differed significantly between the high and low mRNA expression groups. The DSS at 5 years was significantly higher in the low TP mRNA compared with that in the high TP mRNA expression group (83.4 vs. 58.6%, respectively; P=0.005). A Cox proportional hazards model revealed that pathological stage, sex, and TP expression were independent prognostic factors for DSS in patients with stage I and II NSCLC following complete resection. Thus, TP level may be used to monitor treatment efficacy and predict the outcome of NSCLC patients.

14.
Kyobu Geka ; 71(2): 142-145, 2018 Feb.
Article in Japanese | MEDLINE | ID: mdl-29483469

ABSTRACT

A 65-year-old male was admitted to our hospital for evaluation of an abnormal shadow in the left lung field of chest roentgenogram. A chest computed tomography scan revealed an ill-defined nodule in the superior lingular segment of left lung and a calcified nodule in the left pulmonary apex region. A diagnosis of lung adenocarcinoma in the left lingular was made by transbronchial cytology and the left upper lobectomy with lymph node dissection was performed. Pathological diagnosis was primary lung adenocarcinoma in the superior lingular segment of left lung (pT1aN0M0, stage I A) and hamartoma in the left pulmonary apex region. It was considered to be important to discriminate a hamartoma from a metastasic lesion in order to conduct correct treatment.


Subject(s)
Hamartoma/surgery , Lung Neoplasms/surgery , Aged , Hamartoma/diagnostic imaging , Humans , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/pathology , Lymph Node Excision , Male , Pneumonectomy , Tomography, X-Ray Computed
15.
Drug Chem Toxicol ; 41(4): 492-500, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29156995

ABSTRACT

We have conducted animal toxicity tests of chemicals for a chemical safety program implemented by the Ministry of Economy, Trade and Industry of Japan. Here we conducted a combined repeated-dose and reproductive/developmental toxicity screening test of benzene, 1,1'-oxybis-, tetrapropylene derivs. (BOTD). BOTD was administered to 9-week-old Crl:CD(SD) male and female rats by gavage at 0, 40, 200, or 1000 mg/kg/day. Males were treated for 42 days including mating period. Females were treated for 42-53 days through the premating, mating, pregnancy, and until Day 4 of lactation periods. Increases in prothrombin time and activated partial thromboplastin time values were observed only in males at 200 and 1000 mg/kg/day. Hypertrophy of centrilobular hepatocytes was observed with increased liver weight in both sexes at 200 and 1000 mg/kg/day, but there was no histologic evidence of hepatotoxicity. Diffuse hypertrophy of follicular cells in thyroid glands was observed in females at 200 mg/kg/day and in both sexes at 1000 mg/kg/day, with an increased blood cholesterol level in females at 1000 mg/kg/day. The conception index was decreased for females at 1000 mg/kg/day; and no abnormalities were detected in the reproductive indices of implantation, delivery, or pups' condition, although a slight increase in the pups' body weight was noted at birth. Our data indicate a no-observed-adverse-effect level of 40 mg/kg/day for repeated-dose toxicity on the basis of the prolongation of blood coagulating time, and of 200 mg/kg/day for reproductive/developmental toxicity on the basis of the decreased conception index.


Subject(s)
Benzene/toxicity , Reproduction/drug effects , Animals , Blood Coagulation/drug effects , Body Weight/drug effects , Dose-Response Relationship, Drug , Eating/drug effects , Female , Liver/drug effects , Male , Rats , Rats, Sprague-Dawley
16.
Part Fibre Toxicol ; 14(1): 48, 2017 11 28.
Article in English | MEDLINE | ID: mdl-29183341

ABSTRACT

BACKGROUND: The toxicokinetics of nanomaterials are an important factor in toxicity, which may be affected by slow clearance and/or distribution in the body. METHODS: Four types of nickel oxide (NiO) nanoparticles were single-administered intratracheally to male F344 rats at three doses of 0.67-6.0 mg/kg body weight. The rats were sacrificed under anesthesia and the lung, thoracic lymph nodes, bronchoalveolar lavage fluid, liver, and other organs were sampled for Ni burden measurement 3, 28, and 91 days post-administration; Ni excretion was measured 6 and 24 h after administration. Solubility of NiO nanoparticles was determined using artificial lysosomal fluid, artificial interstitial fluid, hydrogen peroxide solution, pure water, and saline. In addition, macrophage migration to trachea and phagosome-lysosome-fusion rate constants were estimated using pulmonary clearance and dissolution rate constants. RESULTS: The wire-like NiO nanoparticles were 100% dissolved by 24 h when mixed with artificial lysosomal fluid (dissolution rate coefficient: 0.18/h); spherical NiO nanoparticles were 12% and 35% dissolved after 216 h when mixed with artificial lysosomal fluid (1.4 × 10-3 and 4.9 × 10-3/h). The largest irregular-shaped NiO nanoparticles hardly dissolved in any solution, including artificial lysosomal fluid (7.8 × 10-5/h). Pulmonary clearance rate constants, estimated using a one-compartment model, were much higher for the NiO nanoparticles with a wire-shape (0.069-0.078/day) than for the spherical and irregular-shaped NiO nanoparticles (0-0.012/day). Pulmonary clearance rate constants of the largest irregular-shaped NiO nanoparticles showed an inverse correlation with dose. Translocation of NiO from the lungs to the thoracic lymph nodes increased in a time- and dose-dependent manner for three spherical and irregular-shaped NiO nanoparticles, but not for the wire-like NiO nanoparticles. Thirty-five percent of the wire-like NiO nanoparticles were excreted in the first 24 h after administration; excretion was 0.33-3.6% in that time frame for the spherical and irregular-shaped NiO nanoparticles. CONCLUSION: These findings suggest that nanomaterial solubility differences can result in variations in their pulmonary clearance. Nanoparticles with moderate lysosomal solubility may induce persistent pulmonary inflammation.


Subject(s)
Lung/metabolism , Nickel/pharmacokinetics , Administration, Inhalation , Animals , Lung/drug effects , Lymph Nodes/metabolism , Lysosomes/chemistry , Male , Metal Nanoparticles/administration & dosage , Metal Nanoparticles/chemistry , Metal Nanoparticles/toxicity , Models, Biological , Nickel/administration & dosage , Nickel/chemistry , Nickel/toxicity , Particle Size , Pneumonia/chemically induced , Pneumonia/metabolism , Rats, Inbred F344 , Solubility , Tissue Distribution , Toxicokinetics
17.
Kyobu Geka ; 70(3): 231-234, 2017 Mar.
Article in Japanese | MEDLINE | ID: mdl-28293013

ABSTRACT

The patient, a 65-year-old woman, visited at her local doctor's office with the chief complaint of pharyngeal pain. After being administered antibacterial drugs, hyperthermia persisted and the pharyngeal pain became exacerbated. She was referred to our hospital and diagnosed as a retropharyngeal abscess and descending necrotizing mediastinitis (DNM). She was urgently hospitalized and surgery was performed. The mediastinal pleura was incised with thoracoscopic guidance and curettage, irrigation, and drainage were performed. Additional drainage was determined to be necessary based on findings from subsequent chest computed tomography and a prolonged inflammatory reaction. Therefore, on hospital day 7, 2nd surgery were performed, and tracheotomy was additionally performed with curettage of the neck abscess. The patient was taken off mechanical ventilation on hospital day 18, and discharged on hospital day 55.


Subject(s)
Mediastinitis/surgery , Aged , Female , Humans , Necrosis
19.
J Appl Toxicol ; 37(4): 502-507, 2017 04.
Article in English | MEDLINE | ID: mdl-27714835

ABSTRACT

Intratracheal administration methods are used to conduct toxicological assessments of inhaled nanoparticles (NPs), and gavage needles or microsprayers are common intratracheal delivery devices. The NP suspension is delivered in a liquid state via gavage needle and as a liquid aerosol via microsprayer. The differences in local pulmonary NP distribution (called the microdistribution) arising from the different states of the NP suspension cause differential pulmonary responses; however, this has yet to be investigated. Herein, using microbeam X-ray fluorescence microscopy, we quantitatively evaluated the TiO2 pulmonary microdistribution (per mesh: 100 µm × 100 µm) in lung sections from rats administered an intratracheal dose of TiO2 NPs (6 mg kg-1 ) via gavage needle or microsprayer. The results revealed that: (i) using a microsprayer appears to reduce the variations in TiO2 content (ng mesh-1 ) among rats (e.g., coefficients of variation, n = 3, microsprayer vs gavage needle: 13% vs 30%, for the entire lungs); (ii) TiO2 appears to be deposited less in the right middle lobes than in the rest of the lung lobes, irrespective of the chosen intratracheal delivery device; and (iii) similar TiO2 contents (ng mesh-1 ) and frequencies are deposited in the lung lobes of rats administered TiO2 NPs via gavage needle or microsprayer. This suggests that the physical state of the administered NP suspension does not markedly alter TiO2 pulmonary microdistribution. The results of this investigation are important for the standardization of intratracheal administration methods. Copyright © 2016 John Wiley & Sons, Ltd.


Subject(s)
Lung/metabolism , Metal Nanoparticles , Administration, Inhalation , Animals , Drug Delivery Systems , Injections, Spinal , Male , Metal Nanoparticles/administration & dosage , Microscopy, Fluorescence , Needles , Rats , Rats, Inbred F344 , Suspensions , Titanium/administration & dosage , Titanium/metabolism
20.
Drug Chem Toxicol ; 40(3): 344-358, 2017 Jul.
Article in English | MEDLINE | ID: mdl-27790921

ABSTRACT

We have carried out animal toxicity tests of chemicals for a chemical safety program implemented by the Ministry of Economy, Trade, and Industry of Japan. Here, we tested 1-tert-butoxy-4-chlorobenzene in a combined repeat-dose and developmental and reproductive toxicity test. The test chemical was administered daily by gavage to 9-week-old Crl:CD (SD) rats at doses of 0, 20, 100, and 500 mg/kg/d. Males were treated for 42 d beginning 14 d before mating. Females were treated from 14 d before mating to day 4 of lactation. Decreased spontaneous locomotion, decreased respiratory rate, and incomplete eyelid opening were observed at 500 mg/kg/d (both sexes), but resolved within 30 min of administration, suggesting central nervous system depression. No notable changes were observed in body weight, food consumption, functional battery tests, or blood test. Increased liver weight with centrilobular or diffuse hepatocyte hypertrophy was observed at 100 and 500 mg/kg/d (both sexes). There were no biochemical or histopathological changes related to hepatotoxicity. Increased kidney weight with basophilic tubules, tubule dilatation, and increased hyaline droplets were observed in males dosed at 100 and 500 mg/kg/d. Immunohistochemical staining indicated α2u-globulin nephropathy, a male rat-specific toxicity. Although kidney weight was also increased in females dosed at 500 mg/kg/d, it was not considered to be an adverse effect because there were no histopathological changes. Pup weights on postnatal day 0 were decreased at 500 mg/kg/d and still decreased on postnatal day 4. Our data indicated the no-observed-adverse-effect-level for repeated-dose and reproductive/developmental toxicity for 1-tert-butoxy-4-chlorobenzene was 100 mg/kg/d.


Subject(s)
Chlorobenzenes/toxicity , Maternal Exposure/adverse effects , Paternal Exposure/adverse effects , Phenyl Ethers/toxicity , Prenatal Exposure Delayed Effects/chemically induced , Reproduction/drug effects , Administration, Oral , Animals , Animals, Newborn , Body Weight/drug effects , Chlorobenzenes/administration & dosage , Dose-Response Relationship, Drug , Eating/drug effects , Female , Male , No-Observed-Adverse-Effect Level , Organ Size/drug effects , Organ Specificity , Phenyl Ethers/administration & dosage , Pregnancy , Rats, Sprague-Dawley , Toxicity Tests
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