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1.
J Mech Behav Biomed Mater ; 129: 105144, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35290854

RESUMO

This study explored the location of MMP-2, -3, -8 in human root dentin and the inhibition of EGCG/EGCG-3Me on dentin-originated collagen proteases activities. Also, the study evaluated EGCG/EGCG-3Me modified etch-and-rinse adhesives (Single Bond 2, SB 2) for their bonding stabilities to intraradicular dentin. Immunostaining and liquid chip analysis demonstrated that MMP-2 and MMP-8 are widely distributed in root dentin while MMP-3 shows a higher fluorescence intensity in the middle and apical third of the root. The contents of MMP-2, -3 and -8 varies in different locations of human tooth root and MMP-2 has the highest content than MMP-3 and MMP-8 at each third of teeth root. Both EGCG and EGCG-3Me showed an inhibitory effect on the root dentin-derived MMPs in a concentration dependent manner (P < 0.05) and the inhibitory activity of EGCG-3ME was stronger than that of EGCG at the same concentration (P < 0.05). EGCG and EGCG-3Me were incorporated separately into the adhesive SB 2 at concentrations of 200, and 400 µg/mL respectively. The immediate push-out strength of SB 2 was not compromised by EGCG/EGCG-3Me modification. EGCG/EGCG-3Me modified adhesive had higher push-out strength than SB 2 after thermocycling, showing no correlation with concentration.


Assuntos
Colagem Dentária , Adesivos Dentinários , Adesivos/análise , Adesivos/farmacologia , Dentina/química , Adesivos Dentinários/química , Humanos , Teste de Materiais , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 2 da Matriz/farmacologia , Metaloproteinase 3 da Matriz/análise , Metaloproteinase 3 da Matriz/farmacologia , Metaloproteinase 8 da Matriz/análise , Metaloproteinase 8 da Matriz/farmacologia , Inibidores de Metaloproteinases de Matriz , Cimentos de Resina/química
3.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(4): 329-334, 2021 Apr 09.
Artigo em Chinês | MEDLINE | ID: mdl-33832033

RESUMO

Objective: To investigate the effect and mechanism of periodontal ligament stem cell (PDLSC) from inflammatory environment on the secretion of interleukin-1ß (IL-1ß) by macrophages. Methods: PDLSCs were pretreated with lipopolysaccharide (LPS) in order to simulate the inflammatory environment. Human monocyte cell line (THP-1) cells were treated with conditioned media collected from healthy and inflammatory PDLSCs respectively and divided into conditioned medium of health PDLSC (CM-H) group and conditioned medium of LPS-PDLSC (CM-LPS) group. After 24 h of co-culture, the condition media were abandoned and THP-1 cells were then cultured for another 24 h. The expression of IL-1ß in THP-1 cells supernatant was detected by enzyme-linked immunosorbent assay (ELISA). Quantitative real time-PCR (qRT-PCR) was used to detect the expression of glucose regulated protein 78 (GRP78), activating transcription factor-6 (ATF6), inositol requiring enzyme 1 (IRE1), protein kinase R-like endoplasmic reticulum kinase (PERK), CCAAT enhancer binding protein homologous protein (CHOP), activating transcription factor-4 (ATF4) and X box binding protein 1 spliced (XBP1s), which were all related with endoplasmic reticulum stress (ERS), in THP-1 cells. The expressions of proteins GRP78 and CHOP were detected by Western blotting. Furthermore, THP-1 cells, which pretreated with ER inhibitor 4-phenylbutyrate (4-PBA) for intervention experiments were grouped by various concentrations of 4-PBA including groups 0 (control group), 1, 10 and 20 mmol/L and treated with condition medium of inflammatory PDLSC. ELISA was used to detect IL-1ß expression and qRT-PCR to detect expression of ERS related genes. Results: ELISA results showed that the expression of IL-1ß in THP-1 cells of group CM-LPS [(31.35±2.11) ng/L] was significantly higher than group CM-H [(8.19±1.51) ng/L] (t=12.60, P<0.01). qRT-PCR results showed that the relative expressions of GRP78, ATF6, IRE1, PERK, CHOP, ATF4 and XBP1s genes in THP-1 cells of group CM-LPS (1.782±0.070, 1.387±0.204, 1.404±0.119, 1.777±0.187, 1.325±0.156, 1.295±0.066 and 1.137±0.149, respectively) were significantly higher than those in group CM-H (P<0.05). In the 4-PBA intervention experiment, compared with group 0 mmol/L, the expressions of GRP78, IRE-1, ATF-6, PERK and CHOP were significantly lower in group 1, 10 and 20 mmol/L (P<0.05). Moreover, compared with control group [(31.23±1.98) ng/L], the expression of IL-1ß in THP-1 cells were significantly lower in group 10 mmol/L [(21.20±0.37) ng/L] and group 20 mmol/L [(23.85±1.80) ng/L] (P<0.05) with ERS inhibited. Conclusions: PDLSC from inflammatory environment could promote IL-1ß secretion of macrophages through upregulating macrophages ERS.


Assuntos
Estresse do Retículo Endoplasmático , Células-Tronco , Chaperona BiP do Retículo Endoplasmático , Humanos , Interleucina-1beta , Macrófagos , Ligamento Periodontal
4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(2): 216-220, 2021 Feb 09.
Artigo em Chinês | MEDLINE | ID: mdl-33557510

RESUMO

Resin cements have been widely employed for bonding all-ceramic restorations in clinical practice, its color stability is directly related to long-term prosthetic effect of restorations. Discoloration of resin cements can be attributed to two causes: endogenous factors are generally related to material compositions and initiation mechanism of polymerization; exogenous factors are mainly related to stimulation of local oral environment. Color stability of resin cements has close relationship with esthetic effect of all-ceramic restorations. The aim of this literature review was to make a presentation and discussion systematically about color stability of resin cements commonly used clinically, its influence factors and influence on all-ceramic restorations, so as to provide a reference for the application of all-ceramic restorations.


Assuntos
Porcelana Dentária , Cimentos de Resina , Cerâmica , Cor , Estética Dentária , Teste de Materiais
5.
Zhonghua Yi Xue Za Zhi ; 100(23): 1783-1788, 2020 Jun 16.
Artigo em Chinês | MEDLINE | ID: mdl-32536123

RESUMO

Objective: To determine whether 60 Gy is superior to standard 50 Gy for definitive concurrent chemoradiation(CCRT) in esophageal squamous cell carcinoma (ESCC) using modern radiation technology in a phase Ⅲ prospective randomized trial. Methods: From April 2013 to May 2017, 331 patients from 22 hospitals who were pathologically confirmed with stage ⅢA-ⅣA ESCC were randomized to 60 Gy or 50 Gy with random number table. Total of 305 patients were analyzed, including 152 in 60 Gy group and 153 in 50 Gy group. The median age was 63 years, 242(79.3%) males and 63(20.7%) females. The median length of primary tumor was 5.6 cm. The clinical characteristics between two groups were comparable. All patients were delivered 2 Gy per fraction, 5 fractions per week. Concurrent weekly chemotherapy with docetaxel (25 mg/m(2)) and cisplatin (25 mg/m(2)) and 2 cycles consolidation chemotherapy with docetaxel (70 mg/m(2)) and cisplatin (25 mg/m(2), d1-3) were administrated. The primary endpoint was local/regional progression-free survival (LRPFS). The data were compared with Pearson chi-square test or Fisher's exact test. Results: At a median follow-up of 27.3 months, the disease progression rate was 37.5% (57/152), 43.8% (67/153) in the high and standard-dose group, respectively (χ(2)=1.251, P=0.263). The 1, 2, 3-year LRPFS rate was 75.4%, 56.8%, 52.1% and 74.2%, 58.4%, 50.1%, respectively (HR: 0.95, 95%CI: 0.69-1.31, P=0.761). The 1, 2, 3-year overall survival rate was 84.1%, 64.8%, 54.1% and 85.4%, 62.9%, 54.0%, respectively (HR: 0.98, 95%CI: 0.71-1.38, P=0.927). The 1, 2, 3-year progression-free survival rate was 70.8%, 54.2%, 48.5% and 65.5%, 51.9%, 45.1%, respectively (HR: 0.93, 95%CI: 0.68-1.26, P=0.621). The incidence rates in toxicities between the two groups were similar except for higher rate of severe pneumonitis in high dose group (χ(2)=11.596, P=0.021). Conclusions: The efficacy in disease control is similar between 60 Gy and 50 Gy using modern radiation technology concurrent with chemotherapy for ESCC. The 50 Gy should be recommended as the regular radiation dose with CCRT for ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Protocolos de Quimioterapia Combinada Antineoplásica , Quimiorradioterapia , Cisplatino , Terapia Combinada , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas do Esôfago/terapia , Feminino , Fluoruracila , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
6.
Ann Oncol ; 24(5): 1312-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23300016

RESUMO

BACKGROUND: Preclinical studies have shown that norepinephrine can directly stimulate tumor cell migration and that this effect is mediated by the beta-adrenergic receptor. PATIENTS AND METHODS: We retrospectively reviewed 722 patients with non-small-cell lung cancer (NSCLC) who received definitive radiotherapy (RT). A Cox proportional hazard model was utilized to determine the association between beta-blocker intake and locoregional progression-free survival (LRPFS), distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival (OS). RESULTS: In univariate analysis, patients taking beta-blockers (n = 155) had improved DMFS (P < 0.01), DFS (P < 0.01), and OS (P = 0.01), but not LRPFS (P = 0.33) compared with patients not taking beta-blockers (n = 567). In multivariate analysis, beta-blocker intake was associated with a significantly better DMFS [hazard ratio (HR), 0.67; P = 0.01], DFS (HR, 0.74; P = 0.02), and OS (HR, 0.78; P = 0.02) with adjustment for age, Karnofsky performance score, stage, histology type, concurrent chemotherapy, radiation dose, gross tumor volume, hypertension, chronic obstructive pulmonary disease and the use of aspirin. There was no association of beta-blocker use with LRPFS (HR = 0.91, P = 0.63). CONCLUSION: Beta-blocker use is associated with improved DMFS, DFS, and OS in this large cohort of NSCLC patients. Future prospective trials can validate these retrospective findings and determine whether the length and timing of beta-blocker use influence survival outcomes.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Doença da Artéria Coronariana/tratamento farmacológico , Hipertensão/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Modelos de Riscos Proporcionais , Receptores Adrenérgicos beta/efeitos dos fármacos , Estudos Retrospectivos , Resultado do Tratamento
7.
Int J Radiat Oncol Biol Phys ; 56(3): 616-25, 2003 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12788166

RESUMO

PURPOSE: To determine the effectiveness of postoperative radiotherapy (RT) in patients with Stage IIB and Stage IIIA non-small-cell lung cancer (NSCLC) treated with induction chemotherapy followed by surgery. METHODS AND MATERIALS: We retrospectively reviewed the treatment records of 98 patients (58 men and 40 women; median age 61 years, range 31-91) with Stage IIB and Stage IIIA NSCLC who were treated with induction chemotherapy followed by surgery at our institution between January 1990 and December 2000. Patients were grouped by treatment (chemotherapy/surgery alone vs. chemotherapy/surgery/RT), by disease stage and nodal classification. The rates of local control (LC), disease-specific survival, disease-free survival, and overall survival (OS) were calculated using the Kaplan-Meier method. RESULTS: Of the 98 patients, 40 had Stage IIB and 58 had Stage IIIA. The clinical disease stage and N stage were significantly greater in those patients who underwent RT than in those who did not; however, no statistically significant differences were identified in the additional characteristics between those receiving and not receiving RT within each stage or nodal group. The overall 5-year actuarial LC rate was 81% in the RT group and 54% in the chemotherapy/surgery-alone group (p = 0.07). Postoperative RT significantly improved the 5-year LC rate in patients with Stage IIIA disease (from 35% to 82%, p = 0.01). Postoperative RT did not significantly improve the 5-year OS rate (30% with RT vs. 49% without) for all patients or for patients with Stage IIIA disease. The disease-specific survival and disease-free survival rates did not differ between the treatment groups. Patients who responded to induction chemotherapy had a significantly greater 5-year OS rate (49%) than did those with stable or progressive disease (22%, p = 0.003). CONCLUSION: Postoperative RT in patients with Stage IIIA NSCLC treated with induction chemotherapy followed by surgery significantly improved LC without improving OS. Significantly improved survival was observed in all patients who responded to induction chemotherapy compared with those with stable or progressive disease.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Grandes/mortalidade , Carcinoma de Células Grandes/patologia , Carcinoma de Células Grandes/radioterapia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Quimioterapia Adjuvante , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Indução de Remissão , Estudos Retrospectivos , Análise de Sobrevida
8.
Yao Xue Xue Bao ; 36(1): 67-70, 2001 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-12579865

RESUMO

AIM: To identify the medicine and search for new medicine resource at the molecular level, the ITS of "Zang Yin Chen"--Swertia mussotti and its adulterant species were sequenced. METHODS: The double-stranded DNA was amplified using PCR systems 9,600 kits and sequenced on an ABI 377 automated sequencer from both directions. RESULTS: The ITS sequences of S. mussotti in different populations showed no variation. It has the unique ITS sequence and shows distinct difference from its adulterant species. In the phylogenetic tree based on the ITS data of S. mussotti and all vicarious species constructed by Paup, S. franchetiana and S. mussotti clustered together with high bootstrap support. CONCLUSION: ITS sequences can be used for the molecular authentication between the S. mussotti and its adulterant species. S. franchetiana can be regarded as a new medicine resource of "Zhang Yin Chen".


Assuntos
DNA de Plantas/genética , Plantas Medicinais/genética , Swertia/genética , Sequência de Bases , DNA Ribossômico/genética , Contaminação de Medicamentos , Swertia/classificação , Tibet
9.
Int J Radiat Oncol Biol Phys ; 38(5): 1045-54, 1997 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-9276371

RESUMO

PURPOSE: In a previous study to determine the effect of partial volume irradiation on damage and morbidity from pneumonitis in mouse lung, a critical determinant of the volume effect was the spatial location of the irradiated subvolume within the lung. The goals of the present study were to (a) define the dose-volume effect curves for radiation pneumonitis in mouse lung, (b) define the threshold volume, and (c) further investigate the spatial heterogeneity of the radiosensitivity of mouse lung. METHODS AND MATERIALS: Eight fractional volumes ranging from 94% to 17% of the lungs of C3Hf/Kam mice were irradiated with single doses ranging from 12 to 22 Gy, depending on the volume irradiated. The fractional volumes irradiated were determined from computed tomographic scans of mouse lung. To determine the effect of location of irradiated subvolume, equivalent volumes in the base and the apex were irradiated by shielding the prescribed adjacent volume in the apex or base respectively. Dose-response curves of breathing rate at 22 weeks and lethality at 28 weeks were constructed for each subvolume irradiated in the apex or base and fitted by logit analysis, and ED50s and LD50s with 95% confidence limits obtained, respectively. Lungs from dead mice or mice sacrificed when moribund were examined for histologic signs of pneumonitis. RESULTS: Irradiation of any of the eight subvolumes in the base yielded a consistently lower isoeffect dose for both assays of radiation pneumonitis than if the same irradiated subvolume was located in the apex. Plots of isoeffect dose for breathing rate as a function of subvolume irradiated in the base or apex showed that these curves were not linear but exhibited a plateau between irradiated volumes of 70% and 80% in both the apex and base. A similar curve was obtained for lethality and volume irradiated in the base. A threshold volume, i.e., irradiation of that volume that should produce no changes in breathing rate or mortality, was dependent on the location of the irradiated subvolume. CONCLUSION: The response of mouse lung to partial volume irradiation is heterogeneous and is critically dependent on the specific location of the irradiated subvolume in the lung, i.e., a given subvolume in the base is consistently more sensitive than the same subvolume in the apex using either breathing rate or lethality as assays of radiation pneumonitis. We suggest that this heterogeneity is due to the anatomy of the tracheobronchial tree, i.e., to the distribution of non-gas exchange-conducting airways in the irradiated volume. These data have implications for the modeling of dose-volume effects in the lung and the prediction of normal tissue complication probabilities for radiation pneumonitis in humans.


Assuntos
Pulmão/efeitos da radiação , Pneumonite por Radiação/patologia , Respiração/efeitos da radiação , Animais , Relação Dose-Resposta à Radiação , Feminino , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C3H , Organismos Livres de Patógenos Específicos
10.
Int J Radiat Oncol Biol Phys ; 38(5): 1055-66, 1997 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-9276372

RESUMO

PURPOSE: Recent studies of Liao et al. and Travis et al. have demonstrated that irradiation of cross-sectional partial volumes contiguous to the base of mouse lung produces a higher incidence of pneumonitis than irradiation of equally sized subvolumes contiguous to the apex. One interpretation of this finding is that the critical target cells for pneumonitis are not distributed uniformly throughout the lung. The purpose of the present study was to test this interpretation by obtaining an estimate of the spatial distribution of the critical target cells for pneumonitis in mouse lung, based on the partial-volume data. METHODS AND MATERIALS: A mathematical model was derived describing the probability of radiation pneumonitis as a function of dose, volume of lung irradiated, and location in the lung of the irradiated subvolume. The model includes a nonparametric description of the spatial target-cell distribution in lung, to be estimated from data. The model was fitted to the lethality data of Liao et al. and Travis et al. to obtain estimates of the proportion of target cells contained in each of various subvolumes of the lung. RESULTS: The results indicate that the critical target cells in mouse lung are concentrated in the base and, to a somewhat lesser extent, in the apex of the lung, with fewer cells in the middle region. The estimated spatial distribution of target cells in mouse lung agrees well with the distribution of alveoli, whose concentration in the midlung is limited by the presence of the major conducting airways. CONCLUSION: Heterogeneity in the spatial distribution of critical target cells in normal tissue implies that the complication probability (NTCP) depends on the location in the organ of the irradiated subvolume, as well as on radiation dose and subvolume size. Calculations using an NTCP model for mouse lung indicate that irradiation of equal subvolumes of lung with the same dose can lead to complication probabilities covering the full range from 0 to 100%, depending only on the location in the lung of the irradiated subvolume.


Assuntos
Pulmão/citologia , Pulmão/efeitos da radiação , Modelos Biológicos , Pneumonite por Radiação/patologia , Animais , Relação Dose-Resposta à Radiação , Camundongos , Tolerância a Radiação
11.
Int J Radiat Oncol Biol Phys ; 32(5): 1359-70, 1995 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-7635776

RESUMO

PURPOSE: The aims of this study were to: (a) define the relationship of dose and volume irradiated to damage and morbidity in mouse lung, (b) determine the threshold volume for morbidity after partial lung irradiation; and (c) determine whether the response to radiation of mouse lung is independent of the region irradiated. METHODS AND MATERIALS: C3Hf/Kam female mice were used in this study. The fractional volume of the lung to be irradiated was determined by two methods, weights and computed tomography (CT) scanning. Two experiments were performed to define the volume effect and to determine whether the response of the mouse lung to radiation was homogeneous. In the first experiment, single doses of x-rays ranging from 12 to 20 Gy were given to partial volumes of 84%, 70%, and 40% including the base, 50%, 33%, and 17% including the apex, to 43% in the middle, and to the sum of 57% as 17% in the apex and 40% in the base. In the second experiment, the same volumes of 50% and 70-75% in the apex and base of the lung were irradiated with single doses ranging from 12-19.25 Gy. Morbidity from radiation pneumonitis was quantitated by two end points, breathing rate and lethality between 12 and 32 weeks after irradiation. Damage was assessed by histopathological evidence of pneumonitis. RESULTS: Clear well-defined dose-response curves were obtained for both breathing rate and lethality after all volumes irradiated. There was a clear volume-dependent shift of the dose-response curves for breathing rate and lethality at 28 weeks after irradiation, the end of the pneumonitis phase of damage, to higher doses compared with these data after whole-lung irradiation. In addition, the slopes of the dose-response curves for irradiation of partial lung volumes were more shallow compared to those after whole-lung irradiation. Increases in breathing rate correlated with lethality when the volume irradiated was equal to or greater than 50% of the reference volume. However, after irradiation of volumes smaller than 40%, breathing rate increases were not accompanied by death. A heterogeneous response of the mouse lung to radiation was observed in the first experiment and confirmed by the second experiment. For a given volume irradiated, the isoeffect dose was always less for the base than for the apex of the lung. The threshold volume for breathing rate changes was less than 17 and 40% when the irradiated volumes involved the apex and base, respectively. For lethality, the threshold volume was between 40 and 70% for the base and greater than 50% for the apex of the lung. Finally, damage as assessed by histological evidence of pneumonitis was observed in the irradiated area only. CONCLUSIONS: (a) The volume effect was resolvable in mice, (b) the volume effect in mouse lung exhibits a clear threshold for morbidity, (c) the threshold volume for morbidity is dependent on the end point, (d) the response of mouse lung is heterogeneous, dependent on the site irradiated, and is always greater for the same volumes irradiated in the base than the apex, and, (e) histopathological damage does not always produce observable morbidity.


Assuntos
Pulmão/efeitos da radiação , Pneumonia/fisiopatologia , Lesões Experimentais por Radiação/fisiopatologia , Animais , Relação Dose-Resposta à Radiação , Feminino , Pulmão/patologia , Pulmão/fisiologia , Camundongos , Camundongos Endogâmicos C3H , Morbidade , Pneumonia/epidemiologia , Pneumonia/patologia , Lesões Experimentais por Radiação/epidemiologia , Lesões Experimentais por Radiação/patologia , Radiografia Torácica , Respiração/efeitos da radiação , Fatores de Tempo , Tomografia Computadorizada por Raios X
12.
Radiat Res ; 139(3): 290-9, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8073111

RESUMO

The effect of unilateral nephrectomy 24 h after irradiation on renal function and death with renal insufficiency as well as histopathological changes in the kidney was assessed. Single doses totaling 8-18 Gy were given bilaterally to unanesthetized female and male C3Hf/Kam mice. Renal function damage was assayed by blood urea nitrogen (BUN) and hematocrit.(Hct). Histological damage was quantified by two parameters: kidney area and number of surviving tubule cells along the renal capsule. The number of glomeruli was scored as an indication of the number of nephrons. Changes in the two functional parameters did not appear sooner after irradiation in the nephrectomized mice than in the non-nephrectomized mice. Rather, less impairment of function was measured by both parameters in the nephrectomized mice but only after radiation doses greater than 12 Gy. The LD50 at 424 days after irradiation was also higher in the nephrectomized mice than that in the mice receiving only irradiation, 13.98 Gy (95% confidence limits = 12.03, 15.93) and 11.71 Gy (95% confidence limits = 10.4, 13.1), respectively, in agreement with the data on function. Unilateral nephrectomy alone induced a 10% increase in size of the contralateral kidney. The dose-response curve for the kidney area from nephrectomized mice was parallel to and displaced above that for non-nephrectomized mice, indicating that the increase in renal mass occurred independent of and was not compromised by radiation. Unilateral nephrectomy alone induced no increase in the number of proximal tubules in the contralateral kidney. However, tubule survival was higher in nephrectomized mice given doses greater than 12 Gy compared with mice receiving only radiation. Fitting the tubule survival data by maximum likelihood analysis gave D0's of 6.7 Gv (95% confidence limits = 6.3, 7.1 Gy) and 3.7 Gy (95% confidence limits = 3.5, 3.8 Gy) for the irradiated nephrectomized mice and irradiated mice, respectively. However, the number of glomeruli was the same for both groups, suggesting that the number of the nephrons did not change. These data suggest that the improvement in renal function in mice nephrectomized 24 h after irradiation of both kidneys compared to those receiving only irradiation was due to tubule hyperplasia and not renal hypertrophy.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Rim/efeitos da radiação , Animais , Nitrogênio da Ureia Sanguínea , Feminino , Hematócrito , Nefropatias/etiologia , Nefropatias/patologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Nefrectomia , Insuficiência Renal/etiologia , Insuficiência Renal/patologia , Fatores de Tempo
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