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1.
Br J Surg ; 108(7): 786-796, 2021 07 23.
Article in English | MEDLINE | ID: mdl-33837380

ABSTRACT

BACKGROUND: This study investigated whether a supervised exercise programme improves quality of life (QoL), fatigue and cardiorespiratory fitness in patients in the first year after oesophagectomy. METHODS: The multicentre PERFECT trial randomly assigned patients to an exercise intervention (EX) or usual care (UC) group. EX patients participated in a 12-week moderate- to high-intensity aerobic and resistance exercise programme supervised by a physiotherapist. Primary (global QoL, QoL summary score) and secondary (QoL subscales, fatigue and cardiorespiratory fitness) outcomes were assessed at baseline, 12 and 24 weeks and analysed as between-group differences using either linear mixed effects models or ANCOVA. RESULTS: A total of 120 patients (mean(s.d.) age 64(8) years) were included and randomized to EX (61 patients) or UC (59 patients). Patients in the EX group participated in 96 per cent (i.q.r. 92-100 per cent) of the exercise sessions and the relative exercise dose intensity was high (92 per cent). At 12 weeks, beneficial EX effects were found for QoL summary score (3.5, 95 per cent c.i. 0.2 to 6.8) and QoL role functioning (9.4, 95 per cent c.i. 1.3 to 17.5). Global QoL was not statistically significant different between groups (3.0, 95 per cent c.i. -2.2 to 8.2). Physical fatigue was lower in the EX group (-1.2, 95 per cent c.i. -2.6 to 0.1), albeit not significantly. There was statistically significant improvement in cardiorespiratory fitness following EX compared with UC (peak oxygen uptake (1.8 ml/min/kg, 95 per cent c.i. 0.6 to 3.0)). After 24 weeks, all EX effects were attenuated. CONCLUSIONS: A supervised exercise programme improved cardiorespiratory fitness and aspects of QoL. TRIAL REGISTRATION: Dutch Trial Register NTR 5045 (www.trialregister.nl/trial/4942).


Subject(s)
Esophageal Neoplasms/rehabilitation , Esophagectomy/rehabilitation , Exercise Therapy/methods , Neoplasm Staging , Quality of Life , Esophageal Neoplasms/diagnosis , Esophageal Neoplasms/surgery , Female , Follow-Up Studies , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
2.
Br J Surg ; 95(2): 169-74, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18161760

ABSTRACT

BACKGROUND: It is questionable whether elective appendicectomy can effectively reduce persistent or recurrent right lower-quadrant abdominal pain due to chronic or recurrent appendicitis. METHODS: This single-centre double-blind randomized clinical trial studied the effects of elective laparoscopic appendicectomy on pain 6 months after operation in patients with persistent or recurrent lower-quadrant pain. A secondary outcome evaluated was the relationship between clinical response and appendiceal histopathology. The analysis was performed on an intention-to-treat basis. RESULTS: Forty patients were randomized to laparoscopic appendicectomy (18) or laparoscopic inspection only (22). Postoperative pain scores differed significantly between the groups, favouring appendicectomy (P = 0.005). Relative risk calculations indicated that there was a 2.4 (95 per cent confidence interval (c.i.) 1.3 to 4.0) times greater chance of improvement in pain after laparoscopic appendicectomy. The number needed to treat was 2.2 (95 per cent c.i. 1.5 to 6.5). There was no association between postoperative pain scores and histopathology findings. CONCLUSION: Persistent or recurrent lower abdominal pain can be treated by elective appendicectomy with significant pain reduction in properly selected cases. Histopathology may not be abnormal. REGISTRATION NUMBER: ISRCTN48831122 (http://www.controlled-trials.com).


Subject(s)
Abdominal Pain/etiology , Appendectomy/methods , Appendicitis/surgery , Elective Surgical Procedures/methods , Laparoscopy/methods , Abdominal Pain/surgery , Adolescent , Adult , Appendicitis/pathology , Chronic Disease , Double-Blind Method , Female , Humans , Male , Pain Measurement , Pain, Postoperative/etiology , Recurrence , Treatment Outcome
3.
J Anal Toxicol ; 28(5): 316-9, 2004.
Article in English | MEDLINE | ID: mdl-15239849

ABSTRACT

A standard operating procedure has been developed for an immunoslotblot assay of sulfur mustard adducts to DNA in human blood and skin for use in a field laboratory. A minimum detectable level of exposure of human blood in vitro (> or = 50 nM) sulfur mustard is feasible with the assay. In the case of human skin, a 1 s exposure to saturated sulfur mustard vapor (830 mg/m(-3)) could still be detected.


Subject(s)
Chemical Warfare Agents/poisoning , DNA Adducts/analysis , Immunoblotting/standards , Mustard Gas/poisoning , Skin/drug effects , Chemical Warfare Agents/chemistry , DNA Adducts/chemistry , Humans , Leukocytes/chemistry , Military Medicine/methods , Mustard Gas/chemistry , Reference Values , Skin/chemistry
5.
Eur J Surg Oncol ; 29(1): 29-31, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12559073

ABSTRACT

AIMS: The Mitotic Activity Index (MAI) is a strong prognostic factor for disease free survival in breast cancer. The MAI is lower in screen detected tumours, correlating with less aggressive biological behaviour in this group. In this study the MAI is compared between screen detected, interval and symptomatic breast cancers. METHODS: Between 1991 and 1999, the MAI was determined in 581 breast cancers, 160 were detected by screening, 66 were interval carcinomas, and 355 were symptomatic breast cancers. Other prognostic factors were also registered. RESULTS: The interval group had a significantly higher median MAI (17-18, range 1-134) than the screen detected group (7-8, range 0-94,P <0.0001). There was no difference with the symptomatic group (MAI 15, range 0-149,P =0.92). CONCLUSIONS: Interval cancers had an intermediate outcome when correlated with other prognostic factors, compared to screen detected and symptomatic cancers.


Subject(s)
Breast Neoplasms/diagnosis , Carcinoma, Ductal, Breast/diagnosis , Mitotic Index , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor/metabolism , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/metabolism , Carcinoma, Ductal, Breast/pathology , Female , Humans , Mass Screening , Middle Aged , Neoplasm Invasiveness , Neoplasm Staging , Netherlands , Prognosis , Receptors, Estrogen/metabolism , Sentinel Lymph Node Biopsy , Women's Health
6.
Breast ; 11(2): 116-9, 2002 Apr.
Article in English | MEDLINE | ID: mdl-14965656

ABSTRACT

It is the purpose of this study to investigate whether breast cancer in patients with a positive family history is detected at an earlier stage with better prognostic markers than breast cancer in patients without a positive family history. In 481 patients, tumour size, tumour type, lymph vessel invasion, blood vessel invasion, receptor state, lymphatic spread, mitotic activity index (MAI) and survival were measured and compared, according to their family history. No difference was found between patients without a family history, patients with first-degree relatives or patients with second-degree relatives with breast cancer. Tumours were detected in the same stages and prognostic factors, MAI and survival were similar in all groups. A positive family history of breast cancer does not lead to earlier detection of breast cancer or a better survival.

7.
Eur J Surg Oncol ; 27(1): 17-20, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11237486

ABSTRACT

INTRODUCTION: After false-positive screening for breast cancer, women are still at risk of developing breast cancer. In this study the incidence of breast cancer in a group of women who had a false-positive outcome is compared with the expected breast cancer incidence. METHODS: Follow-up data of 188 women (mean age 58 years) with a false-positive screening result were collected and analysed for breast cancer development. The mean length of follow-up in the study was 7.4 years. The occurrence of breast cancer was compared to the expected incidence of breast cancer in an age-matched control population using figures from the local cancer registration. RESULTS: The occurrence of breast cancer in the study population (n=7) was not significantly different from the expected incidence of breast cancer in the age-matched control group (n=5). CONCLUSION: There is no relationship between false-positive findings during breast cancer screening and later development of breast cancer. Patients who do not have an increased risk of developing breast cancer (due to family history) should not be followed-up clinically, but should be returned to the screening programme.


Subject(s)
Biopsy , Breast Neoplasms/diagnosis , Mammography , Adult , Aged , Breast Diseases/diagnosis , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , False Positive Reactions , Female , Follow-Up Studies , Humans , Middle Aged , Risk Factors
8.
Breast Cancer Res Treat ; 60(3): 235-40, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10930111

ABSTRACT

The purpose of this study was to evaluate the pain experience of women during mammography for breast cancer screening. Possible associations with personal and medical history, sociodemographics and/or situational factors were studied. It was also investigated whether this pain influenced the intention to return for future breast cancer screening. In the Netherlands, women between 50-75 years are invited for screening every two years. A total of 1200 participants were asked to fill up a questionnaire. The response rate was 79.5% (n = 954), and 945 questionnaires contained adequate information for analyses. A total of 689 women (72.9%) described mammography as mild to severely painful. In this group, compared to the group that reported no pain, the following factors occurred significantly more often: sensitive breasts (P = 0.001), family history of breast diseases (P = 0.017); expected pain based on former mammography (P = 0.001), high education (P = 0.008), anxiety (P = 0.001), breast sensitivity in last three days (P = 0.001), insufficient attention of technologist (P = 0.001). Other factors like age, hormonal status, breast size and hormone use were not associated with the pain experienced. Thirty-two women (3.3%) indicated that they would not attend further screening, 25 (2.6%) reported that the pain might deter them, six women (0.6%) had other reasons, one woman (0.1%) was sure not to come because of severe pain. In conclusion, a large majority of women attending breast cancer screening describes mammography as painful (72.9%). Factors associated with pain were described. Relatively few women (2.7%) indicated that the pain might deter them from future mammography. Recommendations are given to reduce the pain experienced during screening mammography.


Subject(s)
Breast Neoplasms/diagnostic imaging , Mammography/adverse effects , Pain/etiology , Aged , Anxiety/etiology , Attitude of Health Personnel , Female , Humans , Mass Screening , Middle Aged , Pain Measurement , Surveys and Questionnaires
9.
Br J Cancer ; 82(2): 381-4, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10646892

ABSTRACT

We know that screening for breast cancer leads to detection of smaller tumours with less lymph node metastases. Could it be possible that the decrease in mortality after screening is not only caused by this earlier stage, but also by a different mitotic activity index (MAI) of the tumours that are detected by screening? Is MAI a prognostic factor for recurrence-free survival? A retrospective study was carried out of 387 patients with breast cancer, treated at the University Hospital Nijmegen between January 1992 and September 1997. Ninety patients had screen-detected breast cancer, 297 patients had breast cancers detected outside the screening programme. The MAI, other prognostic factors and recurrence-free survival were determined. In non-screen-detected tumours the MAI is twice as high as in screen-detected tumours, even after correction for age took place. The MAI correlated well with other tumour characteristics. The MAI in itself is a prognostic factor for recurrence-free survival. Favourable outcome in screen detected breast cancer is not entirely caused by detecting cancer in early stages: quantitative features such as the MAI indicate a less malignant character of screen detected breast cancer. The MAI is an independent prognostic factor for recurrence-free survival.


Subject(s)
Breast Neoplasms/diagnosis , Mass Screening , Mitotic Index , Age Factors , Aged , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Disease-Free Survival , Female , Humans , Middle Aged , Predictive Value of Tests , Prognosis , Retrospective Studies
10.
Eur J Surg ; 165(3): 193-7, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10231650

ABSTRACT

OBJECTIVE: To find out which risk factors affect outcome after pneumonectomy. DESIGN: Retrospective study. SETTING: Teaching hospital, The Netherlands. SUBJECTS: 62 patients who were treated for bronchial cancer by pneumonectomy between 1984 and 1995. MAIN OUTCOME MEASURE: Hospital mortality and postoperative complications. RESULTS: Hospital mortality increased with age, being 5/51 (10%) in the 40-69 age group and 4/11 (36%) in patients aged 70 or more. In the American Society of Anesthesiologists (ASA) class I group hospital mortality was 8% (2/26), in class II 12% (3/26) and in class III 40% (4/10). Hospital mortality was highest when the FEV1:FVC-ratio was below 55%. Cardiac arrhythmias developed in 8 (13%), early bronchopleural fistulas in 7 (11%), and postpneumonectomy syndrome in 5 (8%). These major complications had a high mortality. CONCLUSION: Respiratory function, ASA class, and age over 70 years are the main prognostic factors for hospital morbidity and mortality after pneumonectomy.


Subject(s)
Pneumonectomy , Adult , Age Distribution , Aged , Carcinoma/classification , Carcinoma/diagnosis , Carcinoma/mortality , Carcinoma/surgery , Elective Surgical Procedures/adverse effects , Elective Surgical Procedures/mortality , Elective Surgical Procedures/statistics & numerical data , Female , Hospital Mortality , Humans , Lung Neoplasms/classification , Lung Neoplasms/diagnosis , Lung Neoplasms/mortality , Lung Neoplasms/surgery , Male , Middle Aged , Netherlands/epidemiology , Pneumonectomy/adverse effects , Pneumonectomy/mortality , Pneumonectomy/statistics & numerical data , Postoperative Complications/epidemiology , Prognosis , Retrospective Studies , Treatment Outcome
11.
Drug Chem Toxicol ; 21 Suppl 1: 131-47, 1998.
Article in English | MEDLINE | ID: mdl-10028407

ABSTRACT

In order to provide a quantitative basis for pretreatment and therapy of intoxications with sulfur mustard (SM) the toxicokinetics of this agent as well as its major DNA-adduct were studied in male hairless guinea pigs for the intravenous, respiratory and percutaneous routes. The study comprised measurement of the concentration-time course of SM in blood and measurement of the concentrations of intact SM and its adduct to guanine in various tissues at several time points after administration of, or exposure to SM. SM was analyzed in blood and tissues by gas chromatography with automated thermodesorption injection and mass-spectrometric detection. DNA-adducts were measured via an immuno-slot-blot method. In contrast with nerve agents of the phosphofluoridate type, SM partitions strongly to various organs, especially the lung, spleen, liver and bone marrow. The respiratory toxicity of SM appears to be local, rather than systemic. Surprisingly, the maximum concentration of SM in blood upon percutaneous exposure to 1 LCt50 (10,000 mg.min.m-3, estimated) is approximately 6-fold higher than that for nose--only exposure to 3 LCt50 (2,400 mg.min.m-3). Pretreatment of hairless guinea pigs with the potential scavengers N-acetyl cysteine or cysteine isopropyl ester did not significantly increase the LCt50-value for nose--only exposure to SM vapor.


Subject(s)
DNA Adducts/pharmacokinetics , DNA Adducts/toxicity , Guanine/metabolism , Mustard Gas/pharmacokinetics , Mustard Gas/toxicity , Administration, Cutaneous , Administration, Inhalation , Animals , Chromatography, Gas , Guinea Pigs , Immunoassay , Injections, Intravenous , Male , Mass Spectrometry , Mustard Gas/adverse effects
12.
J Anal Toxicol ; 21(4): 249-51, 1997.
Article in English | MEDLINE | ID: mdl-9248939

ABSTRACT

The exposure of two Iranian victims of the Iran-Iraq conflict (1980-1988) to sulfur mustard was established by immunochemical and mass spectrometric analysis of blood samples taken 22 and 26 days after alleged exposure. One victim suffered from skin injuries compatible with sulfur mustard intoxication but did not have lung injuries; the symptoms of the other victim were only vaguely compatible with sulfur mustard intoxication. Both patients recovered. Immunochemical analysis was based on detection of the N7-guanine adduct of the agent in DNA from lymphocytes and granulocytes, whereas the N-terminal valine adduct in globin was determined by gas chromatography-mass spectrometry after a modified Edman degradation. The valine adduct levels correspond with those found in human blood after in vitro treatment with 0.9 microM sulfur mustard.


Subject(s)
Blood Cells/drug effects , Chemical Warfare Agents/poisoning , Mustard Gas/poisoning , Persian Gulf Syndrome/etiology , Skin Diseases/chemically induced , Humans , Immunoblotting , Iran , Iraq , Mass Spectrometry , Reproducibility of Results
13.
Neth J Med ; 50(4): 153-9, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9130838

ABSTRACT

BACKGROUND: Strict glucose control is essential to the prevention of diabetic complications. The level of glycaemic control in insulin-treated patients with diabetes mellitus (DM) in a routine clinical setting is not known. METHODS: In a cross-sectional survey comprising 8 hospitals in the Rijnmond area, The Netherlands, age, body mass index (BMI), insulin dose, number of injections, and HbA1c were scored in 712 patients with insulin-dependent DM (IDDM) and 462 patients with non-insulin-dependent DM (NIDDM). RESULTS: In IDDM and NIDDM patients, respectively, age (mean +/- SD) was 40 +/- 17 and 65 +/- 12 years, BMI was 24.1 +/- 3.5 and 27.3 +/- 4.1 kg/m2, daily insulin dose was 49 +/- 18 and 44 +/- 18 U (P < 0.001). Intensive therapy (> or = 4 injections or continuous subcutaneous insulin infusion) was used in 59% of IDDM and 13% of NIDDM patients. HbA1c below the upper normal limit was achieved in 11% of the patients, and within 20% above the upper normal limit in 37%. Obesity was positively associated with HbA1c in NIDDM patients (P < 0.01). A higher insulin dose was associated with higher HbA1c in both IDDM and NIDDM patients (P < 0.01). CONCLUSIONS: Good glycaemic control was established in 37% of our patients. Intensive insulin treatment and higher insulin dose did not improve glucose regulation. Obesity is a risk factor for poor glycaemic control.


Subject(s)
Body Mass Index , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 2/blood , Glycated Hemoglobin/metabolism , Hypoglycemic Agents/administration & dosage , Insulin/administration & dosage , Adult , Aged , Blood Glucose/metabolism , Cross-Sectional Studies , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Dose-Response Relationship, Drug , Humans , Middle Aged , Risk Factors
14.
Mutat Res ; 334(3): 347-56, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7753098

ABSTRACT

An immunochemical assay to detect damage in DNA has been modified to a so-called sandwich ELISA. With this assay DNA damages can be detected that give rise to a certain level of single-strandedness in DNA of white blood cells during partial unwinding of cellular DNA under alkaline conditions. The modified method includes the following steps: incubation of alkali-treated whole blood in the wells of microtiter plates precoated with antibody directed against single-stranded DNA (ssDNA), which results in selective binding of ssDNA, and the subsequent detection of bound ssDNA by incubation with anti-ssDNA antibody alkaline phosphatase conjugate. With this method the amount of damage induced by ionizing radiation in DNA in cells of human blood can be detected within 1 h, after doses as low as 0.2 Gy. The precoating of microtiter plates with anti-ssDNA antibody enables the detection of ssDNA fragments directly in alkali-treated blood samples, isolation of the nucleated cells from the blood is not necessary. Because the DNA is released somewhat faster from lymphocytes than from granulocytes upon alkali treatment, it even appeared possible to discriminate between the effect of the radiation on these cell types in the same blood sample. The method is also applicable to other cell types that can be obtained in suspension.


Subject(s)
DNA Damage , DNA, Single-Stranded/analysis , Enzyme-Linked Immunosorbent Assay/methods , Leukocytes/pathology , Antibodies, Monoclonal , Antibody Specificity , DNA/radiation effects , DNA Repair , DNA, Single-Stranded/immunology , Dose-Response Relationship, Radiation , Gamma Rays , Humans , Leukocytes/chemistry , Leukocytes/immunology , Leukocytes/radiation effects
15.
Chem Res Toxicol ; 7(3): 408-13, 1994.
Article in English | MEDLINE | ID: mdl-8075373

ABSTRACT

As part of a program to develop methods for dosimetry of exposure to sulfur mustard, we developed immunochemical methods for the detection of the major adduct, N7-[2-[(hydroxyethyl)thio]ethyl]guanine (N7-HETE-Gua), formed after alkylation of DNA with sulfur mustard. After immunization of rabbits with calf thymus DNA treated with sulfur mustard, we obtained the antiserum W7/10 with a high specificity for DNA adducts of sulfur mustard. With this serum, a competitive enzyme-linked immunosorbent assay was developed in which sulfur mustard adducts to DNA could be detected with a minimum detectable amount of 1-5 fmol per well and a selectivity that allows detection of one N7-HETE-Gua among 5 x 10(6) unmodified nucleotides in single-stranded DNA. The complications that arise to isolate double-stranded DNA from biological samples and to make the DNA single-stranded without destruction of the sulfur mustard adducts result in about a 20-fold higher limit for adduct detection in DNA from human blood than in single-stranded DNA. Presently, adducts in white blood cells can be detected after exposure of human blood to sulfur mustard concentrations > or = 2 microM. We synthesized N7-HETE-GMP for use as a hapten to generate monoclonal antibodies against this adduct. After immunization of mice with this adduct coupled to the carrier protein keyhole limpet hemocyanin we obtained several hybridomas producing monoclonal antibodies that recognize N7-HETE-Gua, containing an intact imidazolium ring. The sensitivity of the competitive ELISA with the monoclonal antibodies was comparable to that of the assays performed with the rabbit antiserum.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
DNA/chemistry , Leukocytes/metabolism , Mustard Gas/chemistry , Thymus Gland/metabolism , Animals , Antibodies, Monoclonal/immunology , Antibody Specificity , Cattle , DNA/immunology , Enzyme-Linked Immunosorbent Assay , Female , Guanine/analogs & derivatives , Guanine/immunology , Guanine/metabolism , Haptens/chemistry , Haptens/immunology , Hemocyanins , Humans , Immunochemistry , In Vitro Techniques , Leukocytes/chemistry , Leukocytes/drug effects , Mice , Mice, Inbred BALB C/immunology , Mustard Gas/pharmacology , Thymus Gland/chemistry , Thymus Gland/drug effects
16.
Mutat Res ; 274(1): 19-27, 1992 Jun.
Article in English | MEDLINE | ID: mdl-1375329

ABSTRACT

A simple, sensitive and fast immunochemical method has been developed to quantify the amount of DNA damage in cells of human blood after in vitro exposure to ionizing radiation. The technique is based on the enhancement of the radiation-induced single-strandedness, which occurs in DNA regions flanking strand breaks, by a controlled further unwinding of the DNA in an alkaline solution. Subsequently, the DNA is attached to the wall of polystryene cups by passive adsorption. DNA damage is then quantified by determining the extent of single-strandedness with a monoclonal antibody, D1B, directed against single-stranded DNA. D1B binding is assayed with a 'second' antibody, labelled with either an enzyme or europium. The latter gives slightly more reproducible results. No radioactive labelling of DNA is required and the assay takes only 3.5 h after the collection of blood. Damage can be detected after doses as low as 0.5 Gy. The potential broader application of the method is discussed.


Subject(s)
DNA Damage/genetics , DNA, Single-Stranded/analysis , Immunoassay/methods , Antibodies, Monoclonal/metabolism , DNA/radiation effects , Enzyme-Linked Immunosorbent Assay , Europium/metabolism , Humans , Leukocytes
17.
Int J Radiat Biol ; 59(3): 651-60, 1991 Mar.
Article in English | MEDLINE | ID: mdl-1672355

ABSTRACT

The alkaline elution technique for the detection of DNA damage has been adapted to allow application on unlabelled blood cells. Both the induction and subsequent repair have been studied of two classes of DNA damage, viz, single-strand breaks and base damage recognized by the gamma-endonuclease activity in a cell-free extract of Micrococcus luteus bacteria. The high sensitivity of the assay permitted the measurement of induction and repair of base damage after in vitro exposure of full blood under aerobic conditions to biologically relevant doses of gamma-rays (1.5-4.5 Gy). After a radiation dose of 3 Gy about 50% of the base damage was removed within 1.5 h of repair. Base damage could still be detected at 24 h after exposure to 15 Gy.


Subject(s)
DNA Damage , DNA/radiation effects , Leukocytes/radiation effects , Cobalt Radioisotopes , DNA Repair , DNA, Single-Stranded/radiation effects , Dose-Response Relationship, Radiation , Gamma Rays , Humans
18.
Int J Radiat Biol ; 55(5): 747-60, 1989 May.
Article in English | MEDLINE | ID: mdl-2565936

ABSTRACT

An immunochemical method has been developed for quantitative detection of DNA damage in mammalian cells. The method is based on the binding of a monoclonal antibody to single-stranded DNA. The clone producing this antibody (D1B) was obtained as a by-product from fusion of mouse myeloma cells with spleen cells isolated from a mouse immunized with chemically modified DNA. The technique is based upon the determination of the percentage single-strandedness resulting from the time-dependent partial unwinding of cellular DNA under alkaline conditions. Single- and double-strand DNA breaks, or lesions converted into such breaks in alkaline medium, form initiation points for the unwinding. The extent of unwinding from these points under defined conditions is a measure of the number of such sites. The method is rapid, does not require radioactive labelling of DNA or physical separation of single-from double-stranded molecules, is sufficiently sensitive to detect damage induced by 1 Gy of ionizing radiation and needs only small numbers of cells. The usefulness of the technique was demonstrated in a study of the induction of DNA damage and its repair in cultured Chinese hamster cells and in human white blood cells after exposure to 60Co-gamma-rays, and in white blood cells and bone marrow cells of X-irradiated mice. A dose-related DNA unwinding was observed and repair of DNA lesions was observed up to 60 min after irradiation.


Subject(s)
Antibodies, Monoclonal , DNA Damage , DNA, Single-Stranded/immunology , DNA/radiation effects , Animals , Bone Marrow/radiation effects , Bone Marrow Cells , Cell Line , Cricetinae , Humans , Leukocytes/radiation effects , Mice , Mice, Inbred BALB C
20.
Carcinogenesis ; 7(11): 1829-36, 1986 Nov.
Article in English | MEDLINE | ID: mdl-3769130

ABSTRACT

In this study, we determined the wavelength dependence of u.v.-induced pyrimidine dimer formation, cell killing and mutation induction in human diploid skin fibroblasts. Pyrimidine dimers were quantified using the T4 endonuclease V assay, cell killing was measured as loss of colony forming ability and mutation induction was detected at the HPRT locus. U.v. irradiation was performed with monochromatic light of four different wavelengths (254, 297, 302 and 365 nm) and with polychromatic light of a Philips TL-01 lamp (predominantly 312 nm). The relative wavelength dependence for cell killing and mutation induction did not correlate with that for dimer formation. Toxicity and mutagenicity per equivalent initial dimer load increase with increasing wavelength. The relative wavelength dependence for cell killing and mutation induction is essentially the same, except at 365 nm.


Subject(s)
Mutation , Pyrimidine Dimers/biosynthesis , Ultraviolet Rays/adverse effects , Cell Survival/radiation effects , Cells, Cultured , DNA/radiation effects , DNA Repair , Fibroblasts/radiation effects , Humans , Skin/radiation effects
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