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PubMed1995

Frequency of HPRT mutant lymphocytes in a human control population as determined by the T-cell cloning procedure.

The T-cell-cloning assay was established to determine the frequency of hypoxanthine-guanine phosphoribosyltransferase (HPRT) mutant lymphocytes in the presence of the selective agent 6-thioguanine in peripheral blood from a human control population. We investigated 44 healthy adults (blood donors) and found a mean mutant frequency of 7.2 x 10(-6) (geometric mean 5.6 x 10(-6). An elevated mean mutant frequency occurred in smokers as compared to non-smokers. However, a statistically significant increase was only observed between female smokers and female non-smokers while there was only a slight difference in the male group. A significant difference in mutant frequency could be found between individuals younger than 35 years and those above 35. But the difference of the mutant frequency with age showed up only among smokers. No significant effect of the gender was observed. Mutant frequency was inversely related to the cloning efficiency.

Adult↗
PubMed2001

Analysis of lifestyle and behavioral characteristics in Meniere's disease patients and a control population.

A questionnaire was devised to quantify and measure four categories: the behavioral characteristics of Type A, self-restraint and escape; the causes of anxiety; means of relaxation; and symptoms incidental to anxiety. Questionnaire analysis was performed in patients (n = 60) with Meniere's disease and in a control population (n = 936). It was statistically proven that the patient group possessed a stress-causative tendency in behavioral characteristics, felt stronger anxiety and showed more severe symptoms owing to this anxiety. Since the level of anxiety highly correlates with the score of behavioral characteristics and also with severity of symptoms, it seems likely that behavioral characteristics produce the anxiety, which, in turn, results in various symptoms of autonomic nervous disorders. A tendency towards stress-causative behavioral characteristics in Meniere's disease patients may be important in the genesis of endolymphatic hydrops.

Adaptation, Psychological↗
PubMed2005

Divergent selection for uterine capacity in rabbits. II. Correlated response in litter size and its components estimated with a cryopreserved control population.

Our objective was to evaluate the correlated responses to selection for litter size and its components after 10 generations of divergent selection for uterine capacity (UC). A total of 294 intact females from the 11th and 12th generations of divergent selection for high and low UC and from a cryopreserved control population was used (139, 112, and 43 females, respectively). Uterine capacity was assessed as litter size in unilaterally ovariectomized females. Traits recorded on females for up to five parities were litter size (LS) and number born alive (NBA). Laparoscopy was performed in all females at d 12 of their second parity, and the ovulation rate (OR) and number of implanted embryos (IE) were recorded in these females. Embryo survival (ES = IE/OR), fetal survival (FS = LS/IE), and prenatal survival (PS = LS/OR) were computed. Correlated responses in LS and in its components were inferred using Bayesian methods. Correlated responses in LS were asymmetric. The divergence between high and low lines was 2.35 kits, mainly because of a higher correlated response in the low line (1.88 kits). The lower LS in the low line was associated with a lower PS (control - low = 0.14), because of decreases in ES and FS.

Animals↗
PubMed2006

Cartilage oligomeric matrix protein and hyaluronan levels in synovial fluid from horses with osteoarthritis of the tarsometatarsal joint compared to a control population.

REASONS FOR PERFORMING STUDY: Quantification of cartilage oligomeric matrix protein (COMP) levels within synovial fluid from the tarsometatarsal joint has not previously been reported and an effective synovial fluid marker would allow monitoring of disease progression and treatment. OBJECTIVES: To quantify levels of COMP and hyaluronan (HA) in synovial fluid from the tarsometatarsal joint, identify differences in levels from horses with osteoarthritis (OA) of the tarsometatarsal joint compared to a control population and to correlate levels with radiographic changes in horses with OA. METHODS: Synovial fluid was collected from the tarsometatarsal joint of 25 horses without hindlimb lameness (controls) and 25 lame horses, subjected to analgesia of the joint. COMP concentrations were measured using a homologous inhibition ELISA. Immunoblots of synovial fluid from 3 lame horses and 3 controls were performed to identify fragmentation of COMP. Hyaluronan (HA) concentration in synovial fluid was determined using a competition ELISA. Radiographs of the lame horses with OA were scored and correlated with levels of COMP and HA. RESULTS: Concentrations of COMP in OA of the tarsometatarsal joint were significantly lower than in the control samples. An additional fragment band of COMP (approximately 30 kDa) was identified on the immunoblots of the horses with OA and this fragment was not identified in controls. No significant difference was identified in the HA or HA:COMP ratio between lame and control horses. There was no correlation between levels of synovial fluid COMP and HA, and radiographic changes. CONCLUSIONS AND POTENTIAL RELEVANCE: Lowered levels of COMP in synovial fluid of tarsometatarsal joints correlates with the presence of osteoarthritis. However, a single value cannot be used to stage the disease process. Levels of HA may not be a useful marker for this disease. Decreased, rather than increased COMP levels, may reflect significant loss of cartilage in established osteoarthritis. A specific assay for the COMP fragment generated with osteoarthritis may allow the earlier detection of clinical cases.

Animals↗
PubMed1999

Prevalence of the C282Y and H63D polymorphisms in a multi-ethnic control population.

Recently a candidate gene for hereditary hemo-chromatosis, HFE, was identified. The finding raises the possibility for genetic testing to provide earlier detection and more complete genotypic evaluation of hemochromatosis affected individuals. We determined the frequency of the HFE polymorphisms, C282Y and H63D, in a randomly selected multi-ethnic control population for establishment of a hemochromatosis genetic testing program. Prevalence was determined by PCR amplification and restriction enzyme digestion of HFE in 100 Caucasians, 100 Hispanics, and 56 African Americans. Heterozygosity for C282Y was detected in 8% of Caucasians, 3% of Hispanics, and 2% of African Americans. Homozygosity for C282Y was detected in 1% of Caucasians. Heterozygosity for H63D was detected in 24% of Caucasians, 15% Hispanics, and 3.5% of African Americans. Homozygosity for H63D was present in 4% of Caucasians and 1% of Hispanics. One Hispanic case was double heterozygous for C282Y and H63D. These results indicate the highest prevalence of C282Y and H63D in the Caucasian population. Additionally, we demonstrate C282Y and H63D polymorphisms in our Hispanic and African American populations, groups in which prevalence rates remain less defined. Our results support the need for thorough interpretation of genetic results for hereditary hemochromatosis in various ethnic populations.

Alleles↗
PubMed2002

Establishing a control population to screen for the occurrence of nineteen unclassified variants in the BRCA1 gene by denaturing high-performance liquid chromatography.

Numerous missense mutations in BRCA1 and BRCA2 are detected during clinical screening of breast and ovarian cancer patients. Because of the lack of a functional protein assay to determine the functional consequence of these mutations, patients are often frustrated by inconclusive results due to unclassified variants (UV). To determine whether a reported UV is also present in a control collective and therefore more likely be a rare polymorphism than a deleterious mutation, we collected a control population consisting of 95 females and 25 males aged over 60 years (mean 73 years) without a family history of BRCA associated cancers. The age of the control group is beyond the median onset of breast and ovarian cancer with a hereditary background. These controls were analysed for the presence of 19 known UVs in BRCA1 with the DHPLC technique. Only four of the 19 variants (R496H, R866C, S1040N and M1652I) were detected and can be considered polymorphims. However, no firm conclusion can be drawn about the functional relevance of the other 15 variants.

Aged↗
PubMed1999

Hprt mutant frequency and aromatic DNA adduct level in non-smoking and smoking lung cancer patients and population controls.

T cell cloning and 32P-post-labelling methods were used to study the mutant frequency (MF) at the hypoxanthine-guanine phosphoribosyl transferase (hprt) locus and the aromatic DNA adduct level (AL) in peripheral lymphocytes of newly diagnosed lung cancer patients (92 ever-smokers and 87 never-smokers) and matched population controls (82 ever-smokers and 79 never-smokers). Overall, the MF (total mean 20.6 x 10(-6)) and AL (4.1 x 10(-8)) were similar in cases and controls with the same smoking status, indicating that the disease has limited effect on the two endpoints. When cases and controls were combined, the AL was significantly higher in current smokers than in former or never-smokers (P = 0.0003) and the MF was significantly higher in ever-smokers than in never-smokers (P = 0.004). Age affected the MF significantly in ever-smokers (1.6%/year, 95% CI 0.6-2.5, adjusted for pack-years and years since last smoking), especially among cases (2.1%/year, 95% CI 0.5-3.7). An increase of AL with age was observed in currently smoking cases only (2.3%/year, 95% CI 0.3-4.2, adjusted for smoking dose). For currently smoking cases, there was also a more pronounced effect of smoking dose on both endpoints and a significant correlation between AL and MF (r = 0.52, P = 0.04) was observed among those with the highest dose. Our data also provide additional evidence for the different turnover times of smoking-induced DNA adducts and hprt mutations. The stronger increase of MF and AL with age and dose in currently smoking patients compared with controls is consistent with an interaction between smoking and genetic host factors.

Adenocarcinoma↗
PubMed2004

Prostate operations: long-term effects on sexual and urinary function and quality of life. Comparison with an age-matched control population.

The purpose of this study was to investigate the effects of radical prostatectomy (RP) for prostate cancer, transurethral resection of the prostate (TURP) for benign prostate hyperplasia (BPH), and the alterations induced by ageing on quality of life, urinary and sexual function, and bother. We evaluated 283 patients who filled in and returned the questionnaire used. A total of 105 were treated with RP and were selected prostate cancer patients with localised disease without recurrences. An additional 98 underwent TURP for BPH and a third group consisted of 80 apparently healthy men. The general quality of life was estimated by the Rand 36-Item Health Survey 1.0. Urinary function was estimated by the AUA Symptom Index and the UCLA Prostate Cancer Index (urinary function and bother scale). Sexual function and bother, were explored using the Brief Male Sexual Function Inventory for Urology. Patient outcome 2 years post treatment was compared to the pre-treatment status and to that of the matched control population. General quality of life was not affected by RP or TURP, with the exception of an increase in the emotional/well being domain in RP patients to control group levels. After RP there was more bother reported for the urinary function than urinary malfunction itself, while TURP, as expected, restored urinary function and bother to normal population norms. Elderly males had urinary function and bother similar to the operated patients. Estimating sexual function on RP patients, erectile dysfunction (ED) predominates, leading to decreased sexual life. TURP marginally affects sexual life, mainly due to the loss of ejaculation, while in men from the control group, sexual function, although affected, was still present.

Aged↗
PubMed2004

Modified S-pouch neobladder vs ileal conduit and a matched control population: a quality-of-life survey.

OBJECTIVES: To measure the quality-of-life (QoL) outcome and urinary and sexual function and bother after radical cystectomy and different types of urinary tract reconstruction (Bricker vs modified S-pouch neobladder), also assessing differences between them and a normal population. PATIENTS, SUBJECTS AND METHODS: Two groups of patients with bladder cancer were assessed; group 1 comprised 58 (mean age 65 years, mean follow-up 28 months) with an ileal conduit diversion, and group 2, 50 (mean age 61 years, mean follow-up 26 months) with a modified S-pouch neobladder. All were disease-free. Group 3 comprised 54 healthy subjects (a control population) of similar age, gender and comorbidities other than bladder cancer. A QoL questionnaire was used to study changes in QoL, and a specific questionnaire for urinary and sexual function and bother was also constructed. RESULTS: There were no differences in the QoL scores among the three groups; group 3 (control) tended to have a better QoL for all domains except emotional functioning. Urinary function was seriously affected in group 1, with more daytime leakage than in groups 2 and 3 (37.8% vs 10%, P = 0.005, and 9.3%, P = 0.01), night loss of urine (39.5% vs 28%, P = 0.07, and 3.7%, P = 0.002) and urine odour (58.6% vs 4%, and 5.5%, both P = 0.001). Patients in group 2 differed from healthy individuals only in night loss of urine. Consequently urinary bother was more pronounced in group 1, as fewer were satisfied (68.9% vs 86% and 83.2%, both P = 0.03). Sexual function was seriously and similarly affected in groups 1 and 2; the erection rate was 28.9% for group 1, 35.5% for group 2 (P = 0.1) and 83.3% in group 3 (P = 0.003), while firm erections were present at 17.7%, 22.2% (P = 0.2) and 83.3% (P = 0.002). Women reported equivalent dysfunction in all three groups (15.4%, 20% and 16.6%, P = 0.3). Sexual desire was also equal in all groups (48.2%, 50% and 48.1). Patients in group 1 expressed more bother, while those in group 2 seemed more satisfied by their sexual life (84.4%, 68% and 68.5%, P = 0.04). CONCLUSIONS: Radical cystectomy does not affect QoL whichever urinary reconstruction is used, and this implies a determination by the patients to live and adjust to their new conditions. On the contrary, urinary and sexual function are affected and related to the method used to reconstruct the urinary system.

Aged↗