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Anthony A. Frank - One of the best experts on this subject based on the ideXlab platform.

  • Renal Transplacental Carcinogenicity of 3,3-Dimethyl-1-Phenyltriazene in Rats: Relationship of Renal Mesenchymal Tumor to
    2016
    Co-Authors: Congenital Mesoblastic Nephroma, Anthony A. Frank, Daniel J. Thompson, Intralobar Nephrogenic Rests, Jerry R. Heidel, William W. Carlton, Bruce J. Beckwith, Marion Merrell Dow Inc, Zionsville N. Road
    Abstract:

    Exposure of rat embryos to 3,3-dimethyl-1-phenyltriazene (DMPT) results in numerous malformations, but the urogenital system is not affected. In contrast, exposure of rat fetuses to DMPT has been reported to result in renal neoplasms, which were not further classified. To better understand this discrepancy in organot-ropism of the teratogenic and transplacental carcinogenic processes, the present study was undertaken to characterize the neoplasms induced in rat fetuses exposed to DMPT inutero. Renal neoplasms and persistent mesenchyme were observed in 19.2 and 11.5%, respectively, of the offspring of rats treated with 1 mg DMPT/ kg body weight intraperitoneally on gestation days 16, 18, and 20. The majority of these renal lesions were observed in females. The renal neoplasms were mixtures of various types of mesenchymal tissue derivatives including smooth muscle and fibrous connective tissue. These neoplasms would be classified as renal mes-enchymal tumors in rats. Brain neoplasms (numerous types), compound odontomas, and Micrognathism were observed predominantly in male offspring from the same group. This treatment also resulted in decreased body weights, increased incidence of sudden loss of body weight, tremors and ataxia, and hypoplastic testes. Exposure to single intraperitoneal doses of DMPT on gestation day 20 did not produce a classic dose-response pattern: Minimal effects were observed with 10 mg DMPT/kg (occasional renal mesenchymal tumors an

  • Renal transplacental carcinogenicity of 3,3-dimethyl-1-phenyltriazene in rats: relationship of renal mesenchymal tumor to congenital mesoblastic nephroma and intralobar nephrogenic rests.
    Toxicologic Pathology, 1992
    Co-Authors: Anthony A. Frank, Daniel J. Thompson, Jerry R. Heidel, William W. Carlton, J. Bruce Beckwith
    Abstract:

    Exposure of rat embryos to 3,3-dimethyl-1-phenyltriazene (DMPT) results in numerous malformations, but the urogenital system is not affected. In contrast, exposure of rat fetuses to DMPT has been reported to result in renal neoplasms, which were not further classified. To better understand this discrepancy in organotropism of the teratogenic and transplacental carcinogenic processes, the present study was undertaken to characterize the neoplasms induced in rat fetuses exposed to DMPT in utero. Renal neoplasms and persistent mesenchyme were observed in 19.2 and 11.5%, respectively, of the offspring of rats treated with 1 mg DMPT/kg body weight intraperitoneally on gestation days 16, 18, and 20. The majority of these renal lesions were observed in females. The renal neoplasms were mixtures of various types of mesenchymal tissue derivatives including smooth muscle and fibrous connective tissue. These neoplasms would be classified as renal mesenchymal tumors in rats. Brain neoplasms (numerous types), compound odontomas, and Micrognathism were observed predominantly in male offspring from the same group. This treatment also resulted in decreased body weights, increased incidence of sudden loss of body weight, tremors and ataxia, and hypoplastic testes. Exposure to single intraperitoneal doses of DMPT on gestation day 20 did not produce a classic dose-response pattern: Minimal effects were observed with 10 mg DMPT/kg (occasional renal mesenchymal tumors and brain neoplasms), marked effects were observed with 30 mg DMPT/kg (lower incidence rate of most of the alterations observed with 1 mg/kg on gestation days 16, 18, and 20), and no effects were observed with 60 mg DMPT/kg. DMPT administered intraperitoneally at 1 mg/kg body weight on gestation days 16, 18, and 20 is an animal model of transplacental chemically induced renal neoplasms, which provide lesions with similarities to both intralobar nephrogenic rests and congenital mesoblastic nephroma of humans. Why the kidney is a carcinogenic target and not a teratogenic target remains unknown.

  • Teratogenicity of 3,3-dimethyl-1-phenyltriazene: distribution in rats and rat embryos.
    Toxicology letters, 1991
    Co-Authors: Anthony A. Frank, Evelyn A. Kazacos, Daniel J. Thompson
    Abstract:

    3,3-Dimethyl-1-phenyltriazene (DMPT) is a methylating agent which is carcinogenic, teratogenic and mutagenic which, in the rat, provides a reproducible animal model with which to study the basis of chemically-induced Micrognathism. The basis of teratogenic organotropism of DMPT and other methylating teratogens is unknown. The present study was undertaken to determine if limited chemical distribution within the embryo was responsible for the organotropism of DMPT. Whole-embryo autoradiographs and liquid scintillation analysis indicated that although DMPT may have some limitations of chemical distribution within the embryo, these limitations are not sufficient to explain its teratogenic organotropism.

Daniel J. Thompson - One of the best experts on this subject based on the ideXlab platform.

  • Renal Transplacental Carcinogenicity of 3,3-Dimethyl-1-Phenyltriazene in Rats: Relationship of Renal Mesenchymal Tumor to
    2016
    Co-Authors: Congenital Mesoblastic Nephroma, Anthony A. Frank, Daniel J. Thompson, Intralobar Nephrogenic Rests, Jerry R. Heidel, William W. Carlton, Bruce J. Beckwith, Marion Merrell Dow Inc, Zionsville N. Road
    Abstract:

    Exposure of rat embryos to 3,3-dimethyl-1-phenyltriazene (DMPT) results in numerous malformations, but the urogenital system is not affected. In contrast, exposure of rat fetuses to DMPT has been reported to result in renal neoplasms, which were not further classified. To better understand this discrepancy in organot-ropism of the teratogenic and transplacental carcinogenic processes, the present study was undertaken to characterize the neoplasms induced in rat fetuses exposed to DMPT inutero. Renal neoplasms and persistent mesenchyme were observed in 19.2 and 11.5%, respectively, of the offspring of rats treated with 1 mg DMPT/ kg body weight intraperitoneally on gestation days 16, 18, and 20. The majority of these renal lesions were observed in females. The renal neoplasms were mixtures of various types of mesenchymal tissue derivatives including smooth muscle and fibrous connective tissue. These neoplasms would be classified as renal mes-enchymal tumors in rats. Brain neoplasms (numerous types), compound odontomas, and Micrognathism were observed predominantly in male offspring from the same group. This treatment also resulted in decreased body weights, increased incidence of sudden loss of body weight, tremors and ataxia, and hypoplastic testes. Exposure to single intraperitoneal doses of DMPT on gestation day 20 did not produce a classic dose-response pattern: Minimal effects were observed with 10 mg DMPT/kg (occasional renal mesenchymal tumors an

  • Renal transplacental carcinogenicity of 3,3-dimethyl-1-phenyltriazene in rats: relationship of renal mesenchymal tumor to congenital mesoblastic nephroma and intralobar nephrogenic rests.
    Toxicologic Pathology, 1992
    Co-Authors: Anthony A. Frank, Daniel J. Thompson, Jerry R. Heidel, William W. Carlton, J. Bruce Beckwith
    Abstract:

    Exposure of rat embryos to 3,3-dimethyl-1-phenyltriazene (DMPT) results in numerous malformations, but the urogenital system is not affected. In contrast, exposure of rat fetuses to DMPT has been reported to result in renal neoplasms, which were not further classified. To better understand this discrepancy in organotropism of the teratogenic and transplacental carcinogenic processes, the present study was undertaken to characterize the neoplasms induced in rat fetuses exposed to DMPT in utero. Renal neoplasms and persistent mesenchyme were observed in 19.2 and 11.5%, respectively, of the offspring of rats treated with 1 mg DMPT/kg body weight intraperitoneally on gestation days 16, 18, and 20. The majority of these renal lesions were observed in females. The renal neoplasms were mixtures of various types of mesenchymal tissue derivatives including smooth muscle and fibrous connective tissue. These neoplasms would be classified as renal mesenchymal tumors in rats. Brain neoplasms (numerous types), compound odontomas, and Micrognathism were observed predominantly in male offspring from the same group. This treatment also resulted in decreased body weights, increased incidence of sudden loss of body weight, tremors and ataxia, and hypoplastic testes. Exposure to single intraperitoneal doses of DMPT on gestation day 20 did not produce a classic dose-response pattern: Minimal effects were observed with 10 mg DMPT/kg (occasional renal mesenchymal tumors and brain neoplasms), marked effects were observed with 30 mg DMPT/kg (lower incidence rate of most of the alterations observed with 1 mg/kg on gestation days 16, 18, and 20), and no effects were observed with 60 mg DMPT/kg. DMPT administered intraperitoneally at 1 mg/kg body weight on gestation days 16, 18, and 20 is an animal model of transplacental chemically induced renal neoplasms, which provide lesions with similarities to both intralobar nephrogenic rests and congenital mesoblastic nephroma of humans. Why the kidney is a carcinogenic target and not a teratogenic target remains unknown.

  • Teratogenicity of 3,3-dimethyl-1-phenyltriazene: distribution in rats and rat embryos.
    Toxicology letters, 1991
    Co-Authors: Anthony A. Frank, Evelyn A. Kazacos, Daniel J. Thompson
    Abstract:

    3,3-Dimethyl-1-phenyltriazene (DMPT) is a methylating agent which is carcinogenic, teratogenic and mutagenic which, in the rat, provides a reproducible animal model with which to study the basis of chemically-induced Micrognathism. The basis of teratogenic organotropism of DMPT and other methylating teratogens is unknown. The present study was undertaken to determine if limited chemical distribution within the embryo was responsible for the organotropism of DMPT. Whole-embryo autoradiographs and liquid scintillation analysis indicated that although DMPT may have some limitations of chemical distribution within the embryo, these limitations are not sufficient to explain its teratogenic organotropism.

Li Zili - One of the best experts on this subject based on the ideXlab platform.

  • CT measurements of upper airway in the patients of obstructive sleep apnea -hypopnea syndrome associated with Micrognathism
    Chinese Archives of Otolaryngology-head and Neck Surgery, 2005
    Co-Authors: Li Zili
    Abstract:

    OBJECTIVE The dimensions of upper airway in a group of micrognathic patients associated with obstructive sleep apnea-hypopnea syndrome (OSAHS) were measured using CT to explore the mor- phologic characteristics and improve the measurement method. METHODS Nineteen normal volunteers (10 males, 9 females), whose average age was 30.37 years, and 12 micrognathic patients associated with OSAHS (10 males,2 females) were included in this study. All the objects undertook CT scan in head and neck region with 16 array CT machine, 20 axial images were recon- structed from the palate level to the upper edge of arytenoids,anterior-posterior dimension, transverse dimension,and cross section area(CSA) of the upper airway in each image were measured. The maximum, minimum and mean anterior-posterior dimension, trans- verse dimension and CSA in velopharyngeal region, glos- sopharyngeal region and larynpharyngeal region were calculated respectively. RESULTS The differences be- tween OSAHS group and control group were significant on anterior-posterior dimension at all the 20 images, on CSA at 12/20 images, but on transverse dimension only at a few images while anterior-posterior dimensions were quite narrow. All the measurements except the maxi- mum transverse dimension in glossopharyngeal regionshowed significant differences between two groups. CONCLUSION The majority of the narrow upper airway attributes to the decrease of anterior-posterior dimen- sion in micrognathic patients associated with OSAHS, glossopharyngeal region is the narrowest region in all three regions.

J. Bruce Beckwith - One of the best experts on this subject based on the ideXlab platform.

  • Renal transplacental carcinogenicity of 3,3-dimethyl-1-phenyltriazene in rats: relationship of renal mesenchymal tumor to congenital mesoblastic nephroma and intralobar nephrogenic rests.
    Toxicologic Pathology, 1992
    Co-Authors: Anthony A. Frank, Daniel J. Thompson, Jerry R. Heidel, William W. Carlton, J. Bruce Beckwith
    Abstract:

    Exposure of rat embryos to 3,3-dimethyl-1-phenyltriazene (DMPT) results in numerous malformations, but the urogenital system is not affected. In contrast, exposure of rat fetuses to DMPT has been reported to result in renal neoplasms, which were not further classified. To better understand this discrepancy in organotropism of the teratogenic and transplacental carcinogenic processes, the present study was undertaken to characterize the neoplasms induced in rat fetuses exposed to DMPT in utero. Renal neoplasms and persistent mesenchyme were observed in 19.2 and 11.5%, respectively, of the offspring of rats treated with 1 mg DMPT/kg body weight intraperitoneally on gestation days 16, 18, and 20. The majority of these renal lesions were observed in females. The renal neoplasms were mixtures of various types of mesenchymal tissue derivatives including smooth muscle and fibrous connective tissue. These neoplasms would be classified as renal mesenchymal tumors in rats. Brain neoplasms (numerous types), compound odontomas, and Micrognathism were observed predominantly in male offspring from the same group. This treatment also resulted in decreased body weights, increased incidence of sudden loss of body weight, tremors and ataxia, and hypoplastic testes. Exposure to single intraperitoneal doses of DMPT on gestation day 20 did not produce a classic dose-response pattern: Minimal effects were observed with 10 mg DMPT/kg (occasional renal mesenchymal tumors and brain neoplasms), marked effects were observed with 30 mg DMPT/kg (lower incidence rate of most of the alterations observed with 1 mg/kg on gestation days 16, 18, and 20), and no effects were observed with 60 mg DMPT/kg. DMPT administered intraperitoneally at 1 mg/kg body weight on gestation days 16, 18, and 20 is an animal model of transplacental chemically induced renal neoplasms, which provide lesions with similarities to both intralobar nephrogenic rests and congenital mesoblastic nephroma of humans. Why the kidney is a carcinogenic target and not a teratogenic target remains unknown.

Li Nan-fang - One of the best experts on this subject based on the ideXlab platform.

  • Prevalence of obstructive sleep apnea-hypopnea syndrome in hypertensive clinic patients
    Chinese Journal of Hypertension, 2012
    Co-Authors: Li Nan-fang
    Abstract:

    Objective To investigate the prevalence of obstructive sleep apnea-hypopnea syndrome(OSAHS)and its correlation to gender,age and nationality in hypertensives.Methods A total of 3391 hypertensive patients were recruited from the hypertension clinic in People's Hospital of Xinjiang Uygur Autonomous Region from April 1,2009 to June 30,2009.Among which 279 OSAHS cases were enrolled to perform polysomnography who were characterized by symptoms of snoring or daytime sleepiness after history inquiry,or by signs of dumpy neck,Micrognathism,hypertrophy tongue,or unaccountable cyanosis of the lips and tongue with or without physical examination.The prevalence of OSAHS in this cohort was calculated and the related risk factors for OSAHS were analyzed.Results ①The prevalence of OSAHS was 6.7%(228/3391)in hypertensives.And the positive rate of polysomnographic monitoring in suspected OSAHS patients was 81.7%(228/279).Of these participants,the detection rate of OSAHS was obviously higher in males(10.4%) than that in females(2.97%).②The mean age was younger in male cases with OSAHS than in female ones [(46.6±9.8) vs(53.1±9.5)years,P0.01].③The highest prevalence was achieved in the subjects aged from 31 years to 60 years(8.9%).The percentage of severe OSAHS in the elderly was higher than that in young and middle-aged patients(67.9% vs 37.5%,P0.01).④The prevalence in Han,Uighur,Kazakh,Hui,and the other nationalities was 7.6%(174/2287),4.7%(37/780),4.2%(7/145),4.2%(6/144) and 11.4%(4/35)respectively,with a significant difference among the groups(χ+2=11.297,P=0.023).Conclusions In the cohort from hypertension clinic,the OSAHS prevalence among the middle and old aged,male hypertensive patients was obviously higher.The prevalence of OSAHS was different among various nationalities.