Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
J Toxicol Pathol ; 37(2): 45-53, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38584971

RESUMEN

The United States Senate passed the "FDA Modernization Act 2.0." on September 29, 2022. Although the effectiveness of this Bill, which aims to eliminate the mandatory use of laboratory animals in new drug development, is limited, it represents a significant trend that will change the shape of drug applications in the United States and other countries. However, pharmaceutical companies have not taken major steps towards the complete elimination of animal testing from the standpoint of product safety, where they prioritize patient safety. Nonetheless, society is becoming increasingly opposed to animal testing, and efforts will be made to use fewer animals and conduct fewer animal tests as a natural and reasonable response. These changes eventually alter the shape of new drug applications. Based on the assumption that fewer animal tests will be conducted or fewer animals will be used in testing, this study explored bioinformatics and new technologies as alternatives to compensate for reduced information and provide a picture of how future new drug applications may look. The authors also discuss the directions that pharmaceutical companies and nonclinical contract research organizations should adopt to promote the replacement, reduction, and refinement of animals used in research, teaching, testing, and exhibitions.

2.
J Toxicol Pathol ; 34(4): 275-282, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34629730

RESUMEN

The research field of "Toxicologic Pathology" evaluates potentially toxic chemical exposures and chemically mediated illnesses in humans and experimental animals. Comparative studies of chemical exposures between model organisms and humans are essential for the risk assessment of chemicals and human health. Here we review the development and activities of the Japanese Society of Toxicologic Pathology (JSTP) during its 37-year history. Toxicological pathology studies provide many interesting and valuable findings. Rodent cancer bioassay data demonstrate the importance of dose levels, times, and duration of exposures to chemicals that possibly cause human cancers. Studies of toxic injuries in the nasal cavity demonstrate that specific chemical compounds affect different target cells and tissues. These observations are relevant for current air pollution studies in the preventive medicine field. Future toxicological pathology studies will be enhanced by applying molecular pathology with advanced observation techniques. In addition to the nasal cavity, another sense organ such as the tongue should be a potential next program of our mission for risk assessment of inhaled and ingested chemicals. As a message to the younger members of the JSTP, interdisciplinary and global cooperation should be emphasized. Elucidating the mechanisms of toxicologic pathology with a combination of advanced expertise in genetics and molecular biology offers promise for future advances by JSTP members.

3.
J Toxicol Pathol ; 33(2): 77-86, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32425340

RESUMEN

This study aimed to establish a rat chronic kidney disease (CKD) model by studying the effects of a high-phosphorus diet in rats that had undergone partial ligation of the renal arteries (RL). Separate groups of 10-week-old male Slc:Sprague-Dawley rats underwent RL and were fed diets with varying phosphorous levels for a period of 48 days. A marked suppression of body weight gain necessitating humane euthanization occurred on day 28 in rats that had undergone RL and were given high-phosphorus feed. By contrast, the group of intact animals on a high-phosphorus feed exhibited a slightly decreased body weight gain from day 21 and survived until scheduled euthanization. In rats with RL, hematological, blood biochemical, and histopathological analyses demonstrated the presence of CKD-like conditions, particularly in the group that were fed a high-phosphorus diet. Hyperphosphatemia and hypocalcemia were induced by a high-phosphorus diet in both the RL and intact groups, both of which had high levels of FGF23 and parathyroid hormone in the blood. Rats with RL on a high-phosphorus diet showed decreased hematopoiesis by the hematopoietic cell area being narrower in the medullary cavity, proliferation of mesenchymal cells and osteoblasts/osteoclasts, and expansion of the osteoid area, a furthermore generalized vascular lesions, such as calcification, were observed. These findings demonstrate that the partial ligation of the renal arteries combined with a calcium-phosphorus imbalance induced by a high-phosphorus diet serves as an animal model for CKD-like conditions accompanied by bone lesions, helping to elucidate this clinical condition and its underlying molecular mechanisms.

4.
J Toxicol Pathol ; 32(2): 119-126, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31092979

RESUMEN

The Standard for Exchange of Nonclinical Data (SEND), adopted by the US Food and Drug Administration (FDA), is a set of regulations for digitalization and standardization of nonclinical study data; thus, related organizations have begun implementing processes in support of SEND. The Global Editorial and Steering Committee (GESC), which provides oversight of the International Harmonization of Nomenclature and Diagnostic Criteria (INHAND), has prepared the SEND Controlled Terminology (CT) for toxicologic pathology. SEND provides electronic data standards created by the Clinical Data Interchange Standards Consortium (CDISC), and CDISC also collaborates in the implementation of SEND. Furthermore, the Pharmaceutical Users Software Exchange (PhUSE), which includes members of the US FDA, has conducted various activities to promote realistic and effective methods to implement SEND. As we reported in 2015, there is a significant variation in the efficiency and quality of SEND data implementation across pharmaceutical companies and contractors (CROs) globally. To address this problem, the Global SEND Alliance (G-SEND) was established in August 2018 to facilitate the coordination and standardization of SEND datasets across CROs in Asia. This paper reports the first method for organizationally and jointly creating consistent SEND datasets between CROs using G-SEND.

5.
Regul Toxicol Pharmacol ; 102: 23-29, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30572082

RESUMEN

Researchers from the Ramazzini Institute have reported that lifespan dosing of rats with aspartame treatment is associated with an increased overall incidence of malignant tumors, including leukemias/lymphomas, transitional cell carcinomas of the renal pelvis/ureter, and malignant schwannomas of the peripheral nerves. Other carcinogenicity studies conducted on aspartame have shown no such carcinogenic potential in any organ system. Additional data to assess the carcinogenic potential of aspartame, especially in relation to the publications of the Ramazzini Institute, were obtained from a third-party histological evaluation of tissues from a carcinogenicity study previously conducted to assess the potential for aspartame to induce tumors of the brain. The results of this histological evaluation provide no evidence of a tumorigenic effect of aspartame in any organ group, including those organs/tissues reportedly affected in the Ramazzini Institute's studies. The only effects identified were an increased incidence of renal pelvic mineralization and renal pelvic hyperplasia secondary to the irritant properties of the mineralization process. The toxicological significance of these particular findings is widely considered minimal. There is no evidence that aspartame is carcinogenic in rats, at least to doses of 4 g/kg body weight/day administered over a 2-year period.


Asunto(s)
Aspartame/toxicidad , Irritantes/toxicidad , Edulcorantes/toxicidad , Animales , Pruebas de Carcinogenicidad , Femenino , Hiperplasia/inducido químicamente , Hiperplasia/patología , Riñón/efectos de los fármacos , Riñón/patología , Masculino , Neoplasias/inducido químicamente , Ratas Wistar
6.
J Toxicol Sci ; 43(7): 435-442, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29973475

RESUMEN

Teriparatide, a drug used in the treatment of osteoporosis, was administered to rats subcutaneously for the duration of 3 months, at a frequency of either once weekly or once daily to demonstrate the varying levels of anabolic action the drug can have on bone depending on the dosing frequency. The levels of biomarkers in the blood were compared and found to vary in osteocalcin (OC), a biomarker of bone formation, and cross-linked N-telopeptide of type 1 collagen (NTx), a biomarker of bone resorption, according to the dosing frequency. In the once-weekly regimen, teriparatide did not affect NTx levels at any of the doses studied, while OC levels increased with dose, peaking at 72 hr, then returning to normal before the next injection (after 1 week). Bone mineral density (BMD) levels increased moderately with no difference between doses. This was thought to result from the steady state achieved following increases in bone formation and bone absorption. In the once-daily dosing regimen, meanwhile, NTx levels increased with dose, and OC levels were markedly higher when compared to those with the once-weekly dosing. BMD levels were higher than those with the once-weekly dosing, but with no difference between doses. This was considered a result of unlimited, excessive increases in bone formation due to daily administration of the drug. These results suggest that teriparatide promotes normal bone metabolism ("stationary mini-modeling") when administered once weekly, and has an anabolic action with high metabolic turnover ("high-turnover remodeling") when administered once daily.


Asunto(s)
Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/farmacología , Huesos/metabolismo , Colágeno Tipo I/sangre , Osteocalcina/sangre , Osteogénesis/efectos de los fármacos , Osteoporosis/prevención & control , Péptidos/sangre , Teriparatido/administración & dosificación , Teriparatido/farmacología , Animales , Biomarcadores/sangre , Densidad Ósea , Resorción Ósea/sangre , Resorción Ósea/diagnóstico , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Inyecciones Subcutáneas , Masculino , Osteoporosis/metabolismo , Ratas Sprague-Dawley , Factores de Tiempo
7.
J Toxicol Pathol ; 30(3): 201-207, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28798527

RESUMEN

The Standard for Exchange of Nonclinical Data (SEND), introduced by the US Food and Drug Administration (FDA), is a scheme for the computerization, electronic application, and screening of preclinical data. Since its establishment, related organizations have been working together to implement SEND. However, it is difficult for individual pharmaceutical companies that often outsource to achieve complete compliance with SEND; hence, the cooperation of contract research organizations (CROs) and SEND Registered Solution Providers (RSPs) is indispensable. In SEND, most data, including those on pathology findings, are converted into controlled terminology (CT), but it is not a simple process to convert findings or levels of severity in the field of pathology, which is a descriptive science. The authors have successfully completed an FDA trial submission for a toxicology test conducted at a CRO and in doing so acquired important knowledge. This article presents a clear picture of such important knowledge from a pathologist's viewpoint.

8.
J Toxicol Pathol ; 28(2): 57-64, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26028814

RESUMEN

The Standard for the Exchange of Nonclinical Data (SEND), adopted by the US FDA, is part of a set of regulations and guidances requiring the submission of standardized electronic study data for nonclinical and clinical data submissions. SEND is the nonclinical implementation of SDTM (Study Data Tabulation Model), the standard electronic format for clinical regulatory submissions to FDA. SEND, SDTM, and the associated Controlled Terminology have been developed by CDISC (Clinical Data Interchange Standards Consortium). In order to successfully implement SEND, interdisciplinary contributions between sponsors and CROs, need a model for task allocation. This is being undertaken by the Pharmaceutical Users Software Exchange (PhUSE). Because SEND is currently the preferred submission format of the US FDA only and will become required by it starting in December 2016, only American academic societies and companies are actively involved. An exception to this is the INHAND initiative, which leads the way in standardizing terminology for toxicological pathology. On the other hand, international globalization of other clinical and nonclinical practices is not feasible because there are substantial differences between the US and non-US countries in CRO involvement in drug development. Thus, non-US countries must consider and develop approaches to SEND that meet their needs. This paper summarizes the activities of the major organizations involved in SEND development and implementation, discusses the effective use of SEND, and details a compliance scheme (research material of the Showa University School of Medicine) illustrating how pharmaceutical companies can complete a large amount of work up to an FDA application with the effective utilization of CROs and solution providers.

9.
J Toxicol Pathol ; 22(4): 229-46, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22271998

RESUMEN

Specific regions in the rat larynx exhibit cellular changes in response to inhaled xenobiotics. These regions include the base of the epiglottis, ventral pouch, and medial surfaces of the vocal processes of the arytenoid cartilages. 1 , 2 In order to collect information on the usefulness of trimming techniques, the influence of different vehicles, the impact of different application routes in toxicity studies, and differences between induced vs. spontaneous lesions, the data obtained from a large number of inhalation and non-inhalation studies performed in Wistar RCCHan(TM): Wist rats at Harlan Laboratories Ltd Switzerland, all evaluated or reviewed by the same pathologist, were compiled for a detailed review. The value of different trimming techniques was deemed to be greatest for transverse and sagittolongitudinal section techniques, as compared to horizontolongitudinally section techniques. The comparison of lesions encountered in control rats of inhalation studies treated with different vehicles did not reveal differences in the type, distribution pattern, incidence and/or severity of spontaneous lesions. The types of lesions were also independent of different application routes in non-inhalation studies compared to inhalation studies. The pattern of spontaneous lesions in the rodent larynx was determined by degenerative and inflammatory lesions starting most often in the submucosal glands by desiccated secretion followed by mineralization and local inflammation or were induced by impacted foreign bodies. Squamous metaplasia was recorded in the respiratory epithelium overlaying the ventral gland as a spontaneous lesion in male Wistar rats from inhalation studies with a maxim of 20.0% in an inhalation oncogenicity study. Induced metaplastic changes recorded in the larynx were reversible. Other induced lesions in inhalation studies consisted of submucosal edema, necrosis, inflammation and/or granuloma. Induced lesions in non-inhalation studies were found to be exclusively related to reflux laryngitis or food impaction. It is concluded, that in rodents induced lesions of the larynx differ in type, distribution pattern, severity and incidence from spontaneous lesions.

10.
Naunyn Schmiedebergs Arch Pharmacol ; 374(3): 235-48, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17089097

RESUMEN

The present study aimed to investigate the effects of olmesartan, an antagonist for angiotensin II receptor type 1(AT1), on the activation of extracellular signal-regulated kinases (ERK)1/2, tissue remodeling, and pro-inflammatory signals in the right ventricle and lung of mice during the early phase of hypobaric hypoxia. Phosphorylation of ERK1/2 in both tissue types in response to hypoxia peaked at 1-3 days, and declined rapidly in the right ventricle, whereas in the lung it was sustained for at least 8 days. Upregulation of angiotensinogen mRNA was observed in the hypoxic lung at 4-9 days, but not in the hypoxic right ventricle and pulmonary artery. Olmesartan inhibited the hypoxia-induced phosphorylation of ERK1/2 in the lung, but not in the right ventricle. Neither right ventricular hypertrophy nor the thickening of the intrapulmonary arterial wall was ameliorated by olmesartan. However, this drug inhibited the expression of the mRNA for angiotensinogen and several pro-inflammatory factors, including interleukin-6 and inducible nitric oxide synthase in the hypoxic lung. These results suggest that olmesartan blocks a potential positive feedback loop of the angiotensin II-AT1 receptor system, which may lead to attenuate pro-inflammatory signals in the mouse lung, that are associated with hypoxic pulmonary hypertension, without inducing any appreciable effects on the compensatory cardiopulmonary hypertrophy at an early phase of exposure to a hypobaric hypoxic environment.


Asunto(s)
Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Hipertensión Pulmonar/tratamiento farmacológico , Imidazoles/farmacología , Proteína Quinasa 1 Activada por Mitógenos/efectos de los fármacos , Proteína Quinasa 3 Activada por Mitógenos/efectos de los fármacos , Tetrazoles/farmacología , Angiotensinógeno/efectos de los fármacos , Angiotensinógeno/genética , Animales , Regulación de la Expresión Génica/efectos de los fármacos , Ventrículos Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/metabolismo , Hipoxia , Mediadores de Inflamación/metabolismo , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Masculino , Ratones , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Olmesartán Medoxomilo , Fosforilación/efectos de los fármacos , Arteria Pulmonar/efectos de los fármacos , ARN Mensajero/metabolismo , Regulación hacia Arriba
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...