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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(7): 1047-1058, 2023 Jul 06.
Artigo em Chinês | MEDLINE | ID: mdl-37482740

RESUMO

Objective: Compare and analyze the results of the domestic Lanyi AH600 glycated hemoglobin analyzer and other different detection systems to understand the comparability of the detection results of different detectors, and establish the best cut point of Lanyi AH600 determination of haemoglobin A1c (HbA1c) in the diagnosis of diabetes. Methods: Multi center cohort study was adopted. The clinical laboratory departments of 18 medical institutions independently collected test samples from their respective hospitals from March to April 2022, and independently completed comparative analysis of the evaluated instrument (Lanyi AH600) and the reference instrument HbA1c. The reference instruments include four different brands of glycosylated hemoglobin meters, including Arkray, Bio-Rad, DOSOH, and Huizhong. Scatter plot was used to calculate the correlation between the results of different detection systems, and the regression equation was calculated. The consistency analysis between the results of different detection systems was evaluated by Bland Altman method. Consistency judgment principles: (1) When the 95% limits of agreement (95% LoA) of the measurement difference was within 0.4% HbA1c and the measurement score was≥80 points, the comparison consistency was good; (2) When the measurement difference of 95% LoA exceeded 0.4% HbA1c, and the measurement score was≥80 points, the comparison consistency was relatively good; (3) The measurement score was less than 80 points, the comparison consistency was poor. The difference between the results of different detection systems was tested by paired sample T test or Wilcoxon paired sign rank sum test; The best cut-off point of diabetes was analyzed by receiver operating characteristic curve (ROC). Results: The correlation coefficient R2 of results between Lanyi AH600 and the reference instrument in 16 hospitals is≥0.99; The Bland Altman consistency analysis showed that the difference of 95% LoA in Nanjing Maternity and Child Health Care Hospital in Jiangsu Province (reference instrument: Arkray HA8180) was -0.486%-0.325%, and the measurement score was 94.6 points (473/500); The difference of 95% LoA in the Tibetan Traditional Medical Hospital of TAR (reference instrument: Bio-Rad Variant II) was -0.727%-0.612%, and the measurement score was 89.8 points; The difference of 95% LoA in the People's Hospital of Chongqing Liang Jiang New Area (reference instrument: Huizhong MQ-2000PT) was -0.231%-0.461%, and the measurement score was 96.6 points; The difference of 95% LoA in the Taihe Hospital of traditional Chinese Medicine in Anhui Province (reference instrument: Huizhong MQ-2000PT) was -0.469%-0.479%, and the measurement score was 91.9 points. The other 14 hospitals, Lanyi AH600, were compared with 4 reference instrument brands, the difference of 95% LoA was less than 0.4% HbA1c, and the scores were all greater than 95 points. The results of paired sample T test or Wilcoxon paired sign rank sum test showed that there was no statistically significant difference between Lanyi AH600 and the reference instrument Arkray HA8180 (Z=1.665,P=0.096), with no statistical difference. The mean difference between the measured values of the two instruments was 0.004%. The comparison data of Lanyi AH600 and the reference instrument of all other institutions had significant differences (all P<0.001), however, it was necessary to consider whether it was within the clinical acceptable range in combination with the results of the Bland-Altman consistency analysis. The ROC curve of HbA1c detected by Lanyi AH600 in 985 patients with diabetes and 3 423 patients with non-diabetes was analyzed, the area under curve (AUC) was 0.877, the standard error was 0.007, and the 95% confidence interval 95%CI was (0.864, 0.891), which was statistically significant (P<0.001). The maximum value of Youden index was 0.634, and the corresponding HbA1c cut point was 6.235%. The sensitivity and specificity of diabetes diagnosis were 76.2% and 87.2%, respectively. Conclusion: Among the hospitals and instruments currently included in this study, among these four hospitals included Nanjing Maternity and Child Health Care Hospital in Jiangsu Province (reference instrument: Arkray HA8180), Tibetan Traditional Medical Hospital of TAR (reference instrument: Bio-Rad Variant Ⅱ), the People's Hospital of Chongqing Liang Jiang New Area (reference instrument: Huizhong MQ-2000PT), and the Taihe Hospital of traditional Chinese Medicine in Anhui Province (reference instrument: Huizhong MQ-2000PT), the comparison between Lanyi AH600 and the reference instruments showed relatively good consistency, while the other 14 hospitals involved four different brands of reference instruments: Arkray, Bio-Rad, DOSOH, and Huizhong, Lanyi AH600 had good consistency with its comparison. The best cut point of the domestic Lanyi AH600 for detecting HbA1c in the diagnosis of diabetes is 6.235%.


Assuntos
Diabetes Mellitus , Gravidez , Criança , Humanos , Feminino , Hemoglobinas Glicadas , Estudos de Coortes , Diabetes Mellitus/diagnóstico , Sensibilidade e Especificidade , Curva ROC
2.
Zhonghua Yi Xue Za Zhi ; 103(7): 494-499, 2023 Feb 21.
Artigo em Chinês | MEDLINE | ID: mdl-36800772

RESUMO

Objective: To investigate the correlation between balloon volume and Meckel's cave size during percutaneous puncture microballoon compression (PMC) for trigeminal neuralgia and the influence of the compression coefficient (the ratio of balloon volume/Meckel's cave size) on the prognosis. Methods: Seventy-two patients (28 males and 44 females) aged (62±11) years who underwent PMC under general anesthesia for trigeminal neuralgia in the First Affiliated Hospital of Zhengzhou University from February 2018 to October 2020 were retrospectively collected. All patients underwent preoperative cranial magnetic resonance imaging (MRI) to measure Meckel's cave size, intraoperative balloon volume was recorded, and the compression coefficient was calculated. Follow-up visits were performed preoperatively (T0) and 1 d (T1), 1 month (T2), 3 months (T3), and 6 months (T4) postoperatively, either in the outpatient clinic or by telephone, and the Barrow Neurological Institute pain scale (BNI-P) score, the Barrow Neurological Institute facial numbness (BNI-N) score and the occurrence of complications were recorded and compared at each time point. Patients were divided into 3 groups according to different prognoses: patients in group A (n=48) were with no recurrence of pain and mild facial numbness, patients in group B (n=19) were with no recurrence of pain but severe facial numbness, while those in group C (n=5) had recurrence of pain. The differences in balloon volume, Meckel's cave size, and compression coefficient were compared among the three groups, and the correlation between balloon volume and Meckel's cave size in each group was analyzed by Pearson correlation. Results: The effective rate of PMC for trigeminal neuralgia was 93.1% (67/72). At time points from T0 to T4, patients had BNI-P scores [M (Q1, Q3)] of 4.5 (4.0, 5.0), 1.0 (1.0, 1.0), 1.0 (1.0, 1.0), 1.0 (1.0, 1.0) and 1.0 (1.0, 1.0), and BNI-N scores [M (Q1, Q3)] of 1.0 (1.0, 1.0), 4.0 (3.0, 4.0), 3.0 (3.0, 4.0), 3.0 (2.0, 4.0) and 2.0 (2.0, 3.0), respectively. Compared with those at T0, patients had lower BNI-P scores and higher BNI-N scores from T1 to T4 (all P<0.05). In all patients, group A, group B, and group C, the balloon volume was (0.65±0.15), (0.67±0.15), (0.59±0.15) and (0.67±0.17) cm3, respectively, with no statistically significant difference (P>0.05), while the Meckel's cave size was (0.42±0.12), (0.44±0.11), (0.32±0.07), and (0.57±0.11) cm3, with a statistically significant difference (P<0.001). The balloon volumes and Meckel's cave sizes were all linearly and positively correlated (r=0.852, 0.924, 0.937 and 0.969, all P<0.05). The compression coefficient in group A, B and C was (1.54±0.14), (1.84±0.18) and (1.18±0.10), respectively, with a statistically significant difference (P<0.001). There were no serious intraoperative complications such as death, diplopia, arteriovenous fistula, cerebrospinal fluid leak, and subarachnoid hemorrhage. Conclusions: Intraoperative balloon volume during PMC for trigeminal neuralgia is linearly and positively correlated with the volume of the patient's Meckel's cave. The compression coefficient varies among patients with different prognoses and the compression coefficient may be a factor affecting the patient's prognosis.


Assuntos
Neuralgia do Trigêmeo , Feminino , Masculino , Humanos , Hipestesia , Estudos Retrospectivos , Dor , Instituições de Assistência Ambulatorial
3.
Eur Rev Med Pharmacol Sci ; 20(5): 849-52, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27010140

RESUMO

Surgery, chemotherapy and radiotherapy have been the main pillars of cancer treatment. Some of the recent improvements in survival of other cancers can be attributed to novel treatment therapies. Such therapies mostly target specific molecules involved in cancer progression and metastasis. Development and clinical introduction of targeted therapies involve identification of new and potentially important molecules in cancer progression. The next important step is to evaluate its prognostic value. Prognostication by molecular markers is also important as this may identify subgroups of patients in need for additional treatment or not, which was not possible with the traditional clinic-pathological prognosticators. Hypoxic markers have been widely explored in the recent past for their prognostic efficacy in non-small cell lung cancer. The present review article will enlighten importance of hypoxic markers with special reference to non-small cell lung carcinoma.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Idoso , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Hipóxia Celular/fisiologia , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Prognóstico
4.
J Appl Microbiol ; 113(4): 983-91, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22789022

RESUMO

AIMS: To evaluate the in vitro and in vivo effectiveness of egg yolk immunoglobulin (IgY) against periodontal disease-causing Fusobacterium nucleatum. METHODS AND RESULTS: Four White Leghorn hens (120 days old) were immunized with whole Fus. nucleatum cells killed with 1% formaldehyde using three injections provided at 2-week intervals. IgY was produced from egg yolks obtained from these immunized hens using water dilution, two-step salt precipitation and ultrafiltration. This IgY was shown to have a purity of 86·8% based on its optical intensity in the stained SDS-PAGE bands. An enzyme-linked immunosorbent assay indicated a high specificity for the IgY against Fus. nucleatum with a maximum antibody titre of 80 000. The IgY had only weak cross-reactivity with Porphyromonas gingivalis, Prevotella intermedia and Solobacterium moorei. Growth and biofilm formation by Fus. nucleatum were inhibited by IgY at concentrations of 10 and 20 mg ml(-1) . Immunofluorescence and immunoelectron microscope assays revealed a high binding ability of specific IgY, which may explain the in vitro effectiveness of IgY. In an in vivo study, IgY treatment resulted in a marked decrease in alveolar bone loss after Fus. nucleatum infection in a mouse model confirming the effectiveness of IgY against periodontal disease-causing Fus. nucleatum. CONCLUSIONS: IgY effectively inhibited growth and biofilm formation by Fus. nucleatum and prevented the progression of periodontal disease by decreasing alveolar bone loss. SIGNIFICANCE AND IMPACT OF THE STUDY: Specific IgY may have potential for the treatment of periodontal disease.


Assuntos
Perda do Osso Alveolar/prevenção & controle , Biofilmes/efeitos dos fármacos , Fusobacterium nucleatum/efeitos dos fármacos , Imunoglobulinas/farmacologia , Animais , Anticorpos Antibacterianos/isolamento & purificação , Anticorpos Antibacterianos/farmacologia , Especificidade de Anticorpos , Biofilmes/crescimento & desenvolvimento , Galinhas , Reações Cruzadas , Gema de Ovo/imunologia , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Feminino , Fusobacterium nucleatum/crescimento & desenvolvimento , Imunoglobulinas/isolamento & purificação , Masculino , Camundongos
5.
Diabet Med ; 29(7): e47-54, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22211946

RESUMO

AIMS: Mitochondrial DNA (mtDNA) content is essential for maintaining normal mitochondrial function, and the mitochondrial function is critical for the production and the release of insulin in Type 2 diabetes mellitus. We investigated whether peripheral blood mtDNA content was reduced in Type 2 diabetes, and what were the major factors? METHODS: The mtDNA content of peripheral blood in a sample of 147 Type 2 diabetes and 170 normal Chinese subjects was determined by amplification of the mitochondrial gene CYT-B and normalized by a nuclear DNA ß-globin gene. Fasting plasma glucose, HbA(1c) , fasting plasma insulin and lipid profile (HDL-cholesterol, LDL-cholesterol, total cholesterol, triglyceride) were analysed with commercial kits on an automatic analyser. RESULTS: In Type 2 diabetes group, the mean HbA(1c) was 62 mmol/mol (7.8%). Moreover, BMI, systolic blood pressure, diastolic blood pressure, fasting plasma glucose, LDL-cholesterol, triglyceride, fasting plasma insulin and homeostasis model assessment for insulin resistance were significantly higher in Type 2 diabetes group than that in control group. Peripheral blood mtDNA content was 24% lower than that in the controls (1.4 ± 0.5 vs. 1.8 ± 0.7, P < 0.001). The mtDNA content was negatively correlated with BMI, fasting plasma glucose, fasting plasma insulin, homeostasis model assessment for insulin resistance (P < 0.01), and age, triglyceride and LDL-cholesterol levels (P < 0.05); while positively correlated with HDL-cholesterol level (P < 0.05) in both groups. Stepwise regression analysis indicated that HbA(1c), fasting plasma glucose and age of onset were the major factors affecting the mtDNA content in the Type 2 diabetes group; however, BMI was the only variable associated with lower mtDNA content in control group. CONCLUSION: Our results demonstrate that lower peripheral blood mtDNA content is associated with Type 2 diabetes in Chinese individuals, and HbA(1c), fasting plasma glucose and age of onset are the major factors affecting the mtDNA content.


Assuntos
Glicemia/metabolismo , HDL-Colesterol/sangue , LDL-Colesterol/sangue , DNA Mitocondrial/sangue , Diabetes Mellitus Tipo 2/sangue , Hemoglobinas Glicadas/metabolismo , Triglicerídeos/sangue , Adulto , Idade de Início , Povo Asiático , Biomarcadores/sangue , Glicemia/genética , DNA Mitocondrial/genética , Diabetes Mellitus Tipo 2/genética , Jejum , Feminino , Hemoglobinas Glicadas/genética , Humanos , Masculino , Pessoa de Meia-Idade
6.
Zhongguo Zhong Yao Za Zhi ; 25(2): 110-4, 2000 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-12212072

RESUMO

OBJECTIVE: To observe the effect of Sanmiao Mixture Capsules(SMC) on prostate hyperplasia in mice and rats. METHOD: The model of prostate hyperplasia was made by injecting testosterone propionate in to male mice(5 g.kg-1.d-1, 21 d) and rats(3 g.kg-1.d-1, 14 d). The treated group was administered SMC(mice: 36.3 g.kg-1 and 18.2 g.kg-1; rats: 25.2 g.kg-1 and 12.6 g.kg-1), the normal control group 1.9 g.kg-1, and the model control group NS. hours after the last administration serum tests were carried out on E2, AKP and Zn2+. Then the animals were killed, prostates taken out and weighed, index of prostate was calculated and pathological examination performed. RESULT: In the SMC treated group, the prostate weight and index were lowered(P < 0.01) the mean activation of E2 was raised, and the mean concentration of AKP and Zn2+ was inhibited (P < 0.01). CONCLUSION: SMC are helpful in checking prostate hyperplasia in mice and rats, the mechanism being probably related to the raising of activation of E2 as well as to the inhibition of concentration of AKP and Zn2+.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Fitoterapia , Hiperplasia Prostática , Hiperplasia Prostática/tratamento farmacológico , Fosfatase Ácida/sangue , Animais , Estradiol/sangue , Masculino , Camundongos , Plantas Medicinais , Próstata/patologia , Hiperplasia Prostática/sangue , Hiperplasia Prostática/induzido quimicamente , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Testosterona
7.
Plant J ; 17(3): 321-7, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10097390

RESUMO

Here we show that the expression of a cysteine proteinase coincides with several developmental events associated with programmed cell death (PCD) in Solanum melongena (brinjal), i.e. during leaf senescence, fruit senescence, xylogenesis, nucellar cell degeneration and anther senescence. We have isolated a cDNA encoding brinjal cysteine proteinase (SmCP) that shares high (90-92%) amino acid identity to cysteine proteinases of tobacco (CYP-8) and tomato (LCYP-2) that have not been previously reported to be senescence-associated. In contrast, SmCP shows lower (39-41%) amino acid identity to other senescence-related cysteine proteinases and, unlike most of them, it is not preferentially expressed in certain organs or cell types. Northern analysis of leaves, fruits and flowers at different stages of development showed that SmCP expression increased significantly at senescence in leaf and fruit, but was highly expressed throughout flower development. In situ hybridization studies on flower sections using an antisense RNA probe localized the SmCP mRNA to the xylem, the epidermis and the endothecium of the anther and the nucellar cells, suggesting its involvement in PCD during xylogenesis, anther senescence and ovule development, respectively. Its expression during nucellar cell degeneration suggests that protein reserves of the nucellus are released to the developing embryo. Polarity in its pattern of expression in the nucellus of the developing seed (40DAP) further implies a directional flow of these nutrients.


Assuntos
Cisteína Endopeptidases/genética , Solanaceae/enzimologia , Solanaceae/genética , Sequência de Aminoácidos , Apoptose , DNA Complementar/genética , DNA Complementar/isolamento & purificação , DNA de Plantas/genética , DNA de Plantas/isolamento & purificação , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Hibridização In Situ , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , Homologia de Sequência de Aminoácidos , Solanaceae/crescimento & desenvolvimento
8.
Curr Eye Res ; 16(5): 467-74, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9154385

RESUMO

PURPOSE: Previous studies have shown that transketolase is preferentially expressed in the corneal epithelium and comprises up to 10% of the soluble protein of the mature mouse cornea. The aim of this study is to evaluate the expression and distribution of TKT in the different ocular tissues. METHODS: We have used in situ hybridization and immunohistochemistry to localize TKT mRNA and protein in the developing and adult mouse eye. RESULTS: TKT were found to be widely distributed throughout the adult mouse eye. Among the ocular tissues examined, the corneal epithelium exhibited the highest levels of TKT mRNA and protein. Within the epithelial layer, TKT mRNA and protein were differentially distributed with the highest expression occurring in basal cells and the lowest in apical cells, suggesting that TKT expression in the corneal epithelium may be differentiation-related. Enriched expression of TKT was also found in the cornea endothelium, lens epithelium, ciliary body, and iris. Low basal levels of expression were observed in the limbus and conjunctiva. In contrast to the adult eye, TKT expression in the one-day-old mouse eye was homogeneous at low, but detectable levels, suggesting that TKT expression is developmentally regulated in the cornea as well as in the other ocular tissues. In the healing corneal epithelium, TKT expression in the single cell layer of the leading edge was completely suppressed until the cells began to stratify, at which point TKT expression increased markedly. CONCLUSIONS: The results presented here suggest that TKT is differentially expressed and developmentally regulated in the various tissues that comprise the eye.


Assuntos
Olho/enzimologia , Transcetolase/metabolismo , Envelhecimento/metabolismo , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Animais Recém-Nascidos/metabolismo , Córnea/metabolismo , Lesões da Córnea , Imuno-Histoquímica , Hibridização In Situ , Camundongos , RNA Mensageiro/metabolismo , Distribuição Tecidual , Cicatrização/fisiologia
9.
Zhonghua Wai Ke Za Zhi ; 32(8): 499-501, 1994 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-7882780

RESUMO

In this paper, the children, who had undergone the operation with the approach similar to that of Tetralogy Fallot, were selected and divided into 4 groups, according to different kinds of cardioplegia were infused during corrective operation. St. Thomas group (CC group) 24 cases, cold blood cardioplegia group (CBC group) 21 cases, terminal warm blood cardioplegia group (TWBC group) 12 cases, and continuous warm blood cardioplegia group (CWBC group) 12 cases. Through the measurement of left ventricular contraction pressure and CK-Mb release in the postoperative period, the effect of myocardial preservation was better in TWBC and CWBC groups than in CC and CBC groups (P < 0.05), ATP volume of myocardium in TWBC and CWBC groups were higher (17.1 and 18.2 mumol/g) than that in CBC group (2.48 mumol/g) (P < 0.01) CP values were respectively 8.74 mumol/g, 7.63 mumol/g and 5.5 mumol/g (P < 0.05). 9 cases (37%) in CC group needed inotropic drug to assist circulation postoperation, 4 cases (16%) in CBC group, 2 cases (12%) in both TWBC and CWBC group. The results demonstrated that WBC had a better myocardial protection effect.


Assuntos
Soluções Cardioplégicas/uso terapêutico , Parada Cardíaca Induzida , Tetralogia de Fallot/cirurgia , Bicarbonatos/uso terapêutico , Sangue , Cloreto de Cálcio/uso terapêutico , Criança , Pré-Escolar , Humanos , Magnésio/uso terapêutico , Miocárdio/metabolismo , Cloreto de Potássio/uso terapêutico , Cloreto de Sódio/uso terapêutico
10.
Zhonghua Wai Ke Za Zhi ; 32(5): 306-9, 1994 May.
Artigo em Chinês | MEDLINE | ID: mdl-7842950

RESUMO

The present paper has shown the effects of myocardial protection of isolated rat heart which were infused with different kinds of cardioplegia, and made to be arrested in the state of ischemia and absence of oxygen for 120 min. The heart rate, left ventricular constraction pressure and cardiac output volume, the myocardium water content and calcium content and pathological examination of myocardium were observed. The isolated rabbit heart under the circumstances of ischemia and absence of oxygen at 37 degrees C for 20 min Observations of the different kinds of cardioplegia. was observed that the different pH and oxygen content between artery and vein of the heart during the infusion of cardioplegia, the value of left ventricular constraction pressure multiplied by heart rates after reperfusion with autologous artery blood for 20 min. The values of CPK and MDA in right atrial blood, the ATP and CP volume of myocardium and pathologic study of myocardium were carried out. The results demonstrated that the warm blood cardioplegia had a better myocardial protection effect in supplying sufficient oxygen to myocardium during heart arrest, preserving and increasing energy store; controlling reperfusion in jury after ischemia, buffering acidosis and preserving heart status function. Therefore it has great value for improving the safety of the patients with complex and high risk heart diseases in perioperation.


Assuntos
Soluções Cardioplégicas/uso terapêutico , Parada Cardíaca Induzida , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Cálcio/metabolismo , Feminino , Técnicas In Vitro , Masculino , Miocárdio/patologia , Coelhos , Ratos , Ratos Wistar
12.
Radiother Oncol ; 8(1): 79-86, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3809604

RESUMO

The acute effect of small radiation doses per fraction on mouse lip mucosa was investigated in the present study. In order to minimize the amount of additional sparing by regeneration during fractionated irradiations in this rapidly proliferating tissue, the overall treatment time had to be limited to at most 4 days, so that the number of irradiations that could be delivered was limited. Therefore, the concept of partial tolerance, established in the rat spinal cord model, was applied. The present experimental data confirm the validity of using this concept for assessing the effect of small radiation doses on tissues. The results of experiments covering a wide range of fraction sizes show that the isoeffective dose for a given mucosal reaction increases when the dose per fraction is progressively decreased to about 2 Gy per fraction. Further reduction of the size of dose per fraction, however, does not result in a detectable extra increase in the total dose to produce the same level of biological effect. It seems that the dose limit of sparing by fractionation in this rapidly proliferating normal tissue might be situated at larger fraction sizes than 0.6 Gy as estimated on basis of the mathematical linear-quadratic model, using an alpha/beta ratio of 6 Gy measured from data with doses per fraction in the range of 2 to 10 Gy.


Assuntos
Lábio/efeitos da radiação , Mucosa Bucal/efeitos da radiação , Doses de Radiação , Animais , Relação Dose-Resposta à Radiação , Feminino , Camundongos
14.
Int J Radiat Oncol Biol Phys ; 11(11): 1977-83, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-4055455

RESUMO

The kinetics and capacity of repair of sublethal damage in mouse lip mucosa have been investigated. To assess the rate of repair 2 and 5 irradiations have been given with intervals ranging from 1 to 24 hours. It was found that the sublethal damage induced by a dose of approximately 10 Gy was fully recovered in approximately 4 hr. After a dose of 5-6 Gy, cellular repair was completed within 3 hr. The half time of repair (T1/2) was estimated to be approximately 72 min for 10 Gy and approximately 54 min for 5-6 Gy. Although these results suggest that the rate of repair is dependent on the fraction size, the possible influence of the amount of repair of sublethal radiation damage with the various fraction sizes used can not be ruled out. To evaluate the capacity of repair, a single dose, 2, 4 and 10 fractions have been given in a maximal overall time of 3 days in order to minimize the influence of repopulation. The slope of the isoeffective curve was 0.32 and the alpha/beta ratio was 8.5 Gy. This indicates that the capacity of cellular repair of lip mucosa is similar to those of other rapidly proliferating tissues but smaller than those of late responding tissues. The results of the present and other studies demonstrate that there are considerable differences in the repair characteristics between acutely and late responding tissues. These features have to be dealt with when fractionation schedules are markedly altered.


Assuntos
Lábio/efeitos da radiação , Animais , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta a Droga , Cinética , Lábio/patologia , Camundongos , Mucosa/patologia , Mucosa/efeitos da radiação , Fatores de Tempo
15.
Radiat Res ; 101(1): 162-9, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3969442

RESUMO

The repopulation kinetics of the irradiated lip mucosa of mice has been investigated. Split-dose experiments showed that, in this tissue, repopulation starts within 3 days after the first irradiation and increases exponentially within 10 days. To assess the relative importance of protraction and distribution of irradiations as a function of time, 10 fractions were given in (1) 3 days (three irradiations per day with a 4-hr interval), (2) 11 days (daily fractions), or (3) two short courses, each consisting of five fractions given in 1.5 days separated by a rest period of 8 days, with an overall time of 11 days. The results show that by protracting the treatment from 3 to 11 days (with daily irradiations) repopulation accounts for recovery of approximately 13 Gy. Delivering the radiation in two short courses separated by a rest period leads to an additional recovery of approximately 5 Gy. The most plausible explanation for this observation is that repopulation is much more efficient during the rest period between the two courses than during continuous daily irradiation. Although the regimen of two short courses with a rest period spares the acute reaction, it will not enhance the late tolerance. Before thorough knowledge about the repopulation kinetics of the tumors can be gained, caution should be observed for indiscriminate use of split-course multiple-fraction-per-day (MFD) regimens for treating various tumors.


Assuntos
Divisão Celular , Lábio/efeitos da radiação , Mucosa Bucal/efeitos da radiação , Animais , Radioisótopos de Cobalto , Relação Dose-Resposta à Radiação , Feminino , Raios gama , Cinética , Camundongos , Fatores de Tempo
16.
Exp Cell Res ; 152(2): 357-67, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6202535

RESUMO

Isolated rat liver cells were pulse-labelled with tritiated uridine and post-incubated in the presence of an excess of unlabelled uridine and of adenosine analog DRB (5-6-dichloro-1-beta-D-ribofuranosyl benzimidazole). Nuclear radioactivity was detected with high resolution autoradiography. A significant labelling of the interchromatin granules was revealed in these conditions. Pretreatments of cells with low doses of actinomycin D in order to preferentially inhibit ribosomal RNA (rRNA) synthesis prevented the labelling of the interchromatin granules during subsequent DRB treatments. These observations indicate that in DRB-treated cells, the interchromatin granules are sites of transfer or of accumulation of nucleolar RNA. Our results are discussed in connection with our knowledge of the action of DRB on RNA metabolism in mammalian cells and with recent data concerning the still enigmatic interchromatin granules which are present in the nuclei of most cells.


Assuntos
Cromatina/análise , Diclororribofuranosilbenzimidazol/farmacologia , RNA/isolamento & purificação , Ribonucleosídeos/farmacologia , Animais , Autorradiografia , Dactinomicina/farmacologia , Fígado/ultraestrutura , Microscopia Eletrônica , Ratos
17.
Radiother Oncol ; 1(4): 369-74, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6505271

RESUMO

The acute reaction of the lip mucosa of mice after single and fractionated irradiations has been investigated. The mouths of 24 mice were irradiated simultaneously in a single field. It was found that the acute reaction of lip mucosa can easily and reliably be scored. The variation in scoring between different observers is small and the reaction is reproducible. The mucosal reaction starts at day 7, reaches a maximum at about day 11-12 and regresses rapidly during the following 6 to 7 days. The overall reaction period is thus shorter for lip mucosa than for skin in the mouse, indicating a shorter cell cycle time. Dose-response curves can be constructed by plotting the average reaction from day 8 to 17 versus the total dose. The curve of log isoeffect dose for an average reaction level 3 against log number of fractions has a slope of 0.35 for a dose rate of 200 cGy/min and 0.29 for 33 cGy/min. The dose required to induce focal mucosa desquamation is significantly lower than that necessary to produce spotted epidermolysis in skin (16.5 Gy vs. 33 Gy for single dose).


Assuntos
Lábio/efeitos da radiação , Mucosa Bucal/efeitos da radiação , Animais , Relação Dose-Resposta à Radiação , Feminino , Mucosa Intestinal/efeitos da radiação , Camundongos , Modelos Biológicos , Pele/efeitos da radiação
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