Established and emerging methods for assessment of small and large intestinal motility.

BACKGROUND: Gastrointestinal symptoms are common in the general population and may originate from disturbances in gut motility. However, fundamental mechanistic understanding of motility remains inadequate, especially of the less accessible regions of the small bowel and colon. Hence, refinement and validation of objective methods to evaluate motility of the whole gut is important. Such techniques may be applied in clinical settings as diagnostic tools, in research to elucidate underlying mechanisms of diseases, and to evaluate how the gut responds to various drugs. A wide array of such methods exists; however, a limited number are used universally due to drawbacks like radiation exposure, lack of standardization, and difficulties interpreting data. In recent years, several new methods such as the 3D-Transit system and magnetic resonance imaging assessments on small bowel and colonic motility have emerged, with the advantages that they are less invasive, use no radiation, and provide much more detailed information. PURPOSE: This review outlines well-established and emerging methods to evaluate small bowel and colonic motility in clinical settings and in research. The latter include the 3D-Transit system, magnetic resonance imaging assessments, and high-resolution manometry. Procedures, indications, and the relative strengths and weaknesses of each method are summarized.

Quantification and variability in colonic volume with a novel magnetic resonance imaging method.

BACKGROUND: Segmental distribution of colorectal volume is relevant in a number of diseases, but clinical and experimental use demands robust reliability and validity. Using a novel semi-automatic magnetic resonance imaging-based technique, the aims of this study were to describe: (i) inter-individual and intra-individual variability of segmental colorectal volumes between two observations in healthy subjects and (ii) the change in segmental colorectal volume distribution before and after defecation. METHODS: The inter-individual and intra-individual variability of four colorectal volumes (cecum/ascending colon, transverse, descending, and rectosigmoid colon) between two observations (separated by 52 ± 10) days was assessed in 25 healthy males and the effect of defecation on segmental colorectal volumes was studied in another seven healthy males. KEY RESULTS: No significant differences between the two observations were detected for any segments (All p > 0.05). Inter-individual variability varied across segments from low correlation in cecum/ascending colon (intra-class correlation coefficient [ICC] = 0.44) to moderate correlation in the descending colon (ICC = 0.61) and high correlation in the transverse (ICC = 0.78), rectosigmoid (ICC = 0.82), and total volume (ICC = 0.85). Overall intra-individual variability was low (coefficient of variance = 9%). After defecation the volume of the rectosigmoid decreased by 44% (p = 0.003). The change in rectosigmoid volume was associated with the true fecal volume (p = 0.02). CONCLUSIONS & INFERENCES: Imaging of segmental colorectal volume, morphology, and fecal accumulation is advantageous to conventional methods in its low variability, high spatial resolution, and its absence of contrast-enhancing agents and irradiation. Hence, the method is suitable for future clinical and interventional studies and for characterization of defecation physiology.

Adsorption of organic probes on silica through Lewis interactions: a comparison of experimental results and quantum chemical calculations.

The adsorption of organic probe molecules on a partly dehydroxylated silica (SiO(2)) surface has been studied in a non-aquatic and non-polar environment. These results were compared to, verified and explained by quantum chemical calculations on the same systems. Since the systems are water free and since the non-polar solvent cyclohexane is used in the experiments, the quantum chemical calculations are well comparable to the experimental results without any additional terms. The characterized surface was found to contain both Lewis acid and Lewis base sites and a good agreement between the experimentally determined and the calculated data was found.

Genomic profiling of malignant melanoma using tiling-resolution arrayCGH.

Malignant melanoma is an aggressive, heterogeneous disease where new biomarkers for diagnosis and clinical outcome are needed. We searched for chromosomal aberrations that characterize its pathogenesis using 47 different melanoma cell lines and tiling-resolution bacterial artificial chromosome-arrays for comparative genomic hybridization. Major melanoma genes, including BRAF, NRAS, CDKN2A, TP53, CTNNB1, CDK4 and PTEN, were examined for mutations. Distinct copy number alterations were detected, including loss or gain of whole chromosomes but also minute amplifications and homozygous deletions. Most common overlapping regions with losses were mapped to 9p24.3-q13, 10 and 11q14.1-qter, whereas copy number gains were most frequent on chromosomes 1q, 7, 17q and 20q. Amplifications were delineated to oncogenes such as MITF (3p14), CCND1 (11q13), MDM2 (12q15), CCNE1 (19q12) and NOTCH2 (1p12). Frequent findings of homozygous deletions on 9p21 and 10q23 confirmed the importance of CDKN2A and PTEN. Pair-wise comparisons revealed distinct sets of alterations, for example, mutually exclusive mutations in BRAF and NRAS, mutual mutations in BRAF and PTEN, concomitant chromosome 7 gain and 10 loss and concomitant chromosome 15q22.2-q26.3 gain and 20 gain. Moreover, alterations of the various melanoma genes were associated with distinct chromosomal imbalances suggestive of specific genomic programs in melanoma development.

Testosterone levels in relation to oral contraceptive use and the androgen receptor CAG and GGC length polymorphisms in healthy young women.

BACKGROUND: The combined effect from the androgen receptor (AR) CAG and GGC length polymorphisms on testosterone levels has not been studied in young women. METHODS: Testosterone levels were measured in blood drawn on both menstrual cycle days 5-10 and 18-23 in 258 healthy women, aged < or =40 years, from high-risk breast cancer families. CAG and GGC length polymorphisms were analysed by PCR and fragment analyses. All women completed a questionnaire including information on oral contraceptive (OC) use and reproductive factors. RESULTS: OC users had lower median testosterone levels than non-users during cycle days 5-10 and 18-23 (P < or = 0.005 for both). The BRCA mutation status was associated neither with testosterone levels nor with CAG or GGC length polymorphism. The CAG length polymorphism was not associated with testosterone levels. The cumulative number of long GGC alleles (> or =17 repeats) was significantly associated with lower testosterone levels in OC users during cycle days 5-10 (P(trend) =0.014), but not during cycle days 18-23 or in non-users. The interaction between the GGC length polymorphism and OC status was highly significant during cycle days 5-10 (P = 0.002) and near-significant during days 18-23 (P = 0.07). Incident breast cancer was more common in women with two short GGC alleles (log-rank P = 0.003). CONCLUSION: The GGC repeat length was the only significant genetic factor modifying the testosterone levels in current OC users from high-risk families. Homozygosity for the short GGC allele may be linked to the increased risk of early-onset breast cancer after OC exposure in high-risk women.

Insulin-like growth factor-1 genotype predicts breast volume after pregnancy and hormonal contraception and is associated with circulating insulin-like growth factor-1 levels: implications for risk of early-onset breast cancer in young women from hereditary breast cancer families.

BACKGROUND: BRCA1/2 mutations predispose to early-onset breast cancer, especially after oral contraceptive (OC) use and pregnancy. However, the majority of breast cancers might be due to more prevalent low penetrance genes that may also modify the risk in BRCA1/2 mutation carriers. The absence of the IGF1 19-CA repeat allele has been associated with high insulin-like growth factor-1 (IGF-1) levels during OC use in nulliparous women of four different ethnic groups. High IGF-1 levels are linked to an increased risk of early-onset breast cancer and to larger breast volumes in the general population. It has also been hypothesized that women whose breast size increases while exposed to OCs may be at increased risk of future breast cancer. AIM: We explored the effect of the IGF1 genotype, specifically the absence of the common 19-CA repeat allele in the promoter region of the IGF1 gene, in combination with oral contraceptive (OC) use or parity on breast volume and IGF-1 levels. MATERIALS AND METHODS: Two hundred fifty-eight healthy women,

Insulin-like growth factor-1 (IGF1) genotype predicts breast volume after pregnancy and hormonal contraception and is associated with circulating IGF-1 levels: implications for risk of early-onset breast cancer in young women from hereditary breast cancer families.

BRCA1/2 mutations predispose to early-onset breast cancer, especially after oral contraceptive (OC) use and pregnancy. However, the majority of breast cancers might be due to more prevalent low-penetrance genes, which may also modify the risk in BRCA mutation carriers. The absence of the IGF1 19-repeat allele has been associated with high insulin-like growth factor-1 (IGF-1) levels during OC use. High IGF-1 levels are linked to early-onset breast cancer and larger breast volumes in the general population. The goal of this study was to elucidate the relationships between IGF1 genotype, early-onset breast cancer, breast volume, circulating IGF-1 levels and OC use in a prospective cohort of 258 healthy women < or =40 years old from high-risk breast cancer families. All women completed a questionnaire including information on reproductive factors and OC use. We measured the height, weight, breast volumes and plasma IGF-1 levels. IGF-1 levels were similar among parous and nulliparous women not using OCs. In all, 13% had no IGF1 19-repeat allele. There was an interaction between IGF1 genotype and OC use on IGF-1 levels (P=0.026) in nulliparous women and another interaction between IGF1 genotype and parity on breast volume (P=0.01). Absence of the 19-repeat allele was associated with high IGF-1 levels in nulliparous OC users and with larger breast volumes in parous women and OC users. Incident breast cancers were also more common in women without the 19-repeat allele (log rank P=0.002). Our results suggest that lack of the IGF1 19-repeat allele modifies IGF-1 levels, breast volume and possibly early-onset breast cancer risk after hormone exposure in young high-risk women.

Melanoma and nonmelanoma skin cancer in patients with multiple tumours--evidence for new syndromes in a population-based study.

BACKGROUND: The hypotheses that Swedish patients with four or more primary tumours [including at least one cutaneous malignant melanoma (CMM)] harbour an increased number of CDKN2A (formerly p16) germline mutations, and that this group of patients show a predisposition to other tumours, e.g. nonmelanoma skin cancer (NMSC), were studied descriptively. So far the mutation 113insArg explains all CDKN2A-associated CMM in ethnic Swedes. OBJECTIVES: All patients with four or more primary tumours, of which at least one was a CMM, from the Southern Swedish Regional Tumour Registry, between 1958 and 1999, were included in this study. METHODS: Forty-four patients were found and subdivided into three groups according to having multiple CMM (group A) or single CMM +/- NMSC (groups B and C). Screening for the presence of the Swedish founder mutation 113insArg in blood or in tissue blocks was performed. RESULTS: Patients in group A were younger at the time of the first CMM diagnosis than patients in group B and group C. The 113insArg mutation was found in four of 44 patients (9%), three with multiple CMM. In group C (n = 14) no founder mutation was evident, while in group B (n = 15) one mutation carrier was found. Nonmutation carriers with multiple CMM (group A) also had a predilection for meningiomas and neurinomas (four patients) or multiple NMSC (three patients). In group B CMM were especially associated with adenocarcinomas but in group C CMM were associated with multiple NMSC. CONCLUSION: The association between meningiomas and neurinomas (no acoustic neurinoma was seen) might indicate a new syndrome. Patients in groups B and C may harbour unknown genetic defects, which could interact with different environmental risk factors.

Clinical and histopathological features of malignant melanoma in germline CDKN2A mutation families.

Primary cutaneous malignant melanomas (CMMs) from 26 individuals belonging to nine families with an identified mutation were clinically and histopathologically compared with 78 matched CMM controls and with a population-based series of CMMs ( = 667). All tumours were histopathologically re-examined. CDKN2A-associated cases were significantly less invasive compared with the matched controls, with an adjusted odds ratio (adjOR) of 2.9 and a 95% confidence interval (CI) of 1.0-8.1 ( = 0.04). According to the odds ratio (OR) values, CDKN2A-associated cases seemed to have tumours more often located on the head and neck (adjOR 2.9, 95% CI 0.6-13.7), with less inflammation (adjOR 0.7, 95% CI 0.3-1.8) and regression (adjOR 0.6, 95% CI 0.2-1.8) but more frequent histological ulceration (adjOR 1.9, 95% CI 0.6-5.8). In comparison with the population-based material, CDKN2A-associated cases were significantly younger at diagnosis (crude OR 3.5, 95% CI 1.6-7.5, divided at 50 years) and had less regressive reaction in their tumours (crude OR 0.35, 95% CI 0.2-0.8). No significant differences were seen for tumour thickness between the different groups. On multivariate analysis, the overall survival was significantly worse for thicker tumours and older age ( = 0.04 for both). To our knowledge this is the first description of the histopathological features of CMMs from families with mutations in the CDKN2A gene.

Selective urological evaluation in men with febrile urinary tract infection.

OBJECTIVE: To investigate the prevalence and clinical importance of urological abnormalities in men with community-acquired febrile urinary tract infection (UTI). PATIENTS AND METHODS: In this prospective study, 85 men (median age 63 years, range 18--86) were followed for 1 year after an episode of febrile UTI. They were investigated by excretory urography, cysto-urethroscopy, uroflowmetry, digital rectal examination and measurement of postvoid residual urine volume by abdominal ultrasonography. RESULTS: The radiological examination of the upper urinary tract in 83 patients revealed 22 abnormal findings in 19 men. Relevant clinical abnormalities leading to surgical intervention were found in only one patient who had renal calyceal stones. The lower urinary tract investigation disclosed 46 findings in 35 men. In all, surgically correctable disorders were found in 20 patients, of whom 15 had previously unrecognized abnormalities. All patients who required surgery were identified either by a history of voiding difficulties, acute urinary retention at the time of infection, the presence of microscopic haematuria at follow-up after one month, or early recurrent symptomatic UTI. CONCLUSION: Routine imaging studies of the upper urinary tract seem dispensable in men with febrile UTI. To reveal abnormalities of clinical importance, any urological evaluation should primarily be focused on the lower urinary tract.

Vagal nerve stimulation does not unkindle seizures.

The purpose of this study was to investigate a mechanism of action for the effect of vagal nerve stimulation on reducing seizures in patients with complex partial epilepsy. The hypothesis tested was that vagal nerve stimulation has an antikindling effect on epilepsy. The databases of two large clinical trials (E03, E05) were accessed, and statistical methods were applied using logarithmic transforms and regression analysis. Two parameters--duration of a patient's epilepsy before entering the clinical trial and the patient's seizure density before entering the clinical trial--were used as markers of subsequent seizure control during vagal nerve stimulation. In general, there was not a good fit to the regression lines, and the slope of the lines did not conform to the hypothesis. The hypothesis that vagal nerve stimulation may unkindle epileptic seizures was not supported.

Haplotype analysis and age estimation of the 113insR CDKN2A founder mutation in Swedish melanoma families.

Germline mutations in the CDKN2A tumor suppressor gene located on 9p21 have been linked to development of melanomas in some families. A germline 3-bp insertion in exon 2 of CDKN2A, leading to an extra arginine at codon 113 (113insR), has been identified in 17 Swedish melanoma families. Analysis of 10 microsatellite markers, spanning approximately 1 Mbp in the 9p21 region, showed that all families share a common allele for at least one of the markers closest to the CDKN2A gene, suggesting that the 113insR mutation is an ancestral founder mutation. Differences in the segregating haplotypes, due to meiotic recombinations and/or mutations in the short-tandem-repeat markers, were analyzed further to estimate the age of the mutation. Statistical analysis using a maximum likelihood approach indicated that the mutation arose 98 generations (90% confidence interval: 52-167 generations), or approximately 2,000 years, ago. Thus, 113insR would be expected to have a more widespread geographic distribution in European and North American regions with ancestral connections to Sweden. Alternatively, CDKN2A may lie in a recombination hot spot region, as suggested by the many meiotic recombinations in this narrow approximately 1-cM region on 9p21.

Paracrine stimulation of capillary endothelial cell migration by endometrial tissue involves epidermal growth factor and is mediated via up-regulation of the urokinase plasminogen activator receptor.

Endometrial angiogenesis is not well studied, but has potential as a model for studies of physiological angiogenesis. Migration as well as proliferation of vascular endothelial cells are modulated by other endometrial cells. This study analyzes the chemotactic signal released from endometrial tissue in a wound assay using human microvascular endothelial cells. Endometrial tissue explants stimulate migration, and this effect is significantly weaker with explants taken at midcycle than those obtained earlier or later in the cycle. Migration is inhibited more than 50% by either blocking antibodies to the urokinase plasminogen activator receptor (uPAR) or enzymatic removal of uPAR from the cell surface. Also, migration is inhibited more than 50% by antibodies to epidermal growth factor (EGF), but not by antibodies to vascular endothelial growth factor or basic fibroblast growth factor. The combination of anti-EGF and anti-uPAR antibodies does not further reduce the response, suggesting that these antibodies target a common pathway. Conditioned medium from endometrial explants contains EGF, and EGF stimulates the migration of endothelial cells in a dose-dependent way. This effect is completely blocked by antibodies to uPAR. These data suggest up-regulation of the uPA system by EGF. Conditioned medium from EGF-treated cells contains less uPA than medium from control cells. In contrast, binding of radiolabeled uPA reveals an increased number of uPA-binding sites in EGF-treated cells. Increased expression of uPAR potentially increases the activation and assembly of focal adhesion sites, a prerequisite for cell migration. We conclude that the endometrial migratory signal has two components. The major part of the signal is blocked by antibodies to EGF, and the response is mediated via up-regulation of uPAR in the endothelial cells. The other part of the signal is unknown, and the response does not involve uPAR. Decreased endometrial chemotactic signal at midcycle is probably related to decreased release of EGF, which is secondary to increased binding to endometrial cell membranes.

Somatic deletions in hereditary breast cancers implicate 13q21 as a putative novel breast cancer susceptibility locus.

A significant proportion of familial breast cancers cannot be explained by mutations in the BRCA1 or BRCA2 genes. We applied a strategy to identify predisposition loci for breast cancer by using mathematical models to identify early somatic genetic deletions in tumor tissues followed by targeted linkage analysis. Comparative genomic hybridization was used to study 61 breast tumors from 37 breast cancer families with no identified BRCA1 or BRCA2 mutations. Branching and phylogenetic tree models predicted that loss of 13q was one of the earliest genetic events in hereditary cancers. In a Swedish family with five breast cancer cases, all analyzed tumors showed distinct 13q deletions, with the minimal region of loss at 13q21-q22. Genotyping revealed segregation of a shared 13q21 germ-line haplotype in the family. Targeted linkage analysis was carried out in a set of 77 Finnish, Icelandic, and Swedish breast cancer families with no detected BRCA1 and BRCA2 mutations. A maximum parametric two-point logarithm of odds score of 2.76 was obtained for a marker at 13q21 (D13S1308, theta = 0.10). The multipoint logarithm of odds score under heterogeneity was 3.46. The results were further evaluated by simulation to assess the probability of obtaining significant evidence in favor of linkage by chance as well as to take into account the possible influence of the BRCA2 locus, located at a recombination fraction of 0.25 from the new locus. The simulation substantiated the evidence of linkage at D13S1308 (P < 0.0017). The results warrant studies of this putative breast cancer predisposition locus in other populations.

High frequency of multiple melanomas and breast and pancreas carcinomas in CDKN2A mutation-positive melanoma families.

BACKGROUND: : Inherited mutations in the CDKN2A tumor suppressor gene, which encodes the p16(INK4a) protein, and in the cyclin-dependent kinase 4 (CDK4) gene confer susceptibility to cutaneous malignant melanoma. We analyzed families with two or more cases of melanoma for germline mutations in CDKN2A and CDK4 to elucidate the contribution of these gene defects to familial malignant melanoma and to the occurrence of other cancer types. METHODS: : The entire CDKN2A coding region and exon 2 of the CDK4 gene of an affected member of each of 52 families from southern Sweden with at least two cases of melanoma in first- or second-degree relatives were screened for mutations by use of polymerase chain reaction-single-strand conformation polymorphism analysis. Statistical tests were two-sided. RESULTS: : CDKN2A mutations were found in 10 (19%) of the 52 families. Nine families carried an identical alteration consisting of the insertion of arginine at position 113 of p16(INK4a), and one carried a missense mutation, in which the valine at position 115 was replaced with a glycine. The 113insArg mutant p16(INK4a) was unable to bind cdk4 and cdk6 in an in vitro binding assay. Six of the 113insArg families had at least one member with multiple primary melanomas; the 113insArg families also had a high frequency of other malignancies-in particular, breast cancer (a total of eight cases compared with the expected 2.1; P =.0014) and pancreatic cancer (a total of six cases compared with the expected 0.16; P<.0001). Families with breast cancer also had a propensity for multiple melanomas in females, suggesting that a sex-dependent factor may modify the phenotypic expression of CDKN2A alterations. CONCLUSIONS: : Our findings confirm that the majority of CDKN2A-associated melanoma families in Sweden are due to a single founder mutation. They also show that families with the CDKN2A 113insArg mutation have an increased risk not only of multiple melanomas and pancreatic carcinoma but also of breast cancer.

A longitudinal cohort study of elderly women with urinary tract infections.

AIMS: the prevalence of urinary tract infections (UTI), urinary incontinence (UI), estrogen-use and overall mortality in a cohort of elderly women who had been treated for UTI in 1985-86 was re-assessed 10 years later. MATERIAL AND METHODS: a random sample of 6000 women from the birth cohorts 1900, 1905, 1910, 1915 and 1920 were invited in 1986 to complete a questionnaire about UTI, UI and estrogen use (response rate 70%; n = 4206). Treatment with antibiotics for UTI during 1985-86 was reported by 688 (17%) women. In 1995 a similar questionnaire was sent to the women from this group who were still alive (n = 434). Mortality in the women with a history of UTI was compared with an aged-matched control group of women who did not have UTI during 1985-86. RESULTS: the questionnaire was completed and returned by 361 (83%) women. Treatment for at least one UTI during the last 9 years was reported by 219 (61%) women. The number of episodes varied: 35% had one to two UTI, 28% had three to four UTI, 27% five to ten UTI and 10% had had more than 10 UTI. In 1986, the prevalence of UI was higher in women with a history of UTI than in the total population sample (30 vs. 17%; P < 0.001). The prevalence of UI had increased from 30% in 1986 to 33% in 1995 (P < 0.05). Mortality in the women with a history of UTI was higher than in the aged-matched control group (37 vs. 28%; P < 0.001). A total of 162 (45%) women had received estrogen therapy at some time after the age of 60 years and 140 (39%) reported that they were currently taking low potency estrogens. CONCLUSION: elderly women with a history of UTI had a continued high occurrence of UTI and UI, and overall mortality was higher in these women than in an age-matched control group of women from the total population.

Plasma nitrate as an index of nitric oxide formation in patients with acute infectious diseases.

In humans, the role of nitric oxide (NO) in host defence is controversial. We prospectively studied plasma levels of nitrate, the stable end-product of NO formation, during acute infection in 43 patients controlled with regard to dietary nitrate/nitrite. During acute gastroenteritis the mean plasma nitrate level was significantly increased compared with at recovery 4-5 weeks later (118 vs. 32.5 micromol/l; p < 0.001), in contrast with the findings in patients with acute pneumonia (PN; 34.6 vs. 42.8 micromol/l) or febrile urinary tract infection (UTI; 27.7 vs. 31.3 micromol/l). In a second group of 20 retrospectively studied patients with severe PN or UTI, of whom 70% were bacteraemic, no significantly increased nitrate levels could be demonstrated during the acute stage of infection. These findings indicate that increased NO production, as measured by plasma nitrate, is not a general finding in patients with acute infectious diseases, but may rather be associated with certain pathogens or sites of infection.

Prostatic involvement in men with febrile urinary tract infection as measured by serum prostate-specific antigen and transrectal ultrasonography.

OBJECTIVE: To determine the frequency of prostatic involvement in men with community-acquired febrile urinary tract infection. PATIENTS AND METHODS: This prospective study included 70 men (18-85 years old) who had a fever of >/=38.0 degrees C, symptoms or signs of urinary tract infection and a positive urine culture. Serum prostate-specific antigen (PSA) was measured and transrectal ultrasonography of the prostate and seminal vesicles performed during the acute phase of the disease and during a 1-year follow-up. RESULTS: Although only six patients had a tender prostate on digital rectal examination, the initial serum PSA level was elevated in 58 (83%) patients (median 14 ng/mL, range 0.54-140). There was no correlation between PSA levels, patient age, inflammatory response to infection or presence of positive blood cultures. Despite a rapid decline in PSA level after one month, there was a protracted decrease in some patients. After 3 months the median prostate volume was reduced by 31% (range 11-54; P<0.001) in 46 of 55 patients examined, and the width of the right and left seminal vesicle was reduced by 14% and 22%, respectively. The reductions in PSA and prostate volume were significantly correlated (r=0.36, 95% confidence interval 0.09-0.58; P=0.01). CONCLUSION: These results show that the prostate and seminal vesicles are frequently involved in men with febrile urinary tract infection and that PSA may be a useful marker of prostatic infection. The slow decline of PSA levels in some patients after appropriate antibiotic treatment indicates a protracted healing process and should be considered when PSA is used to detect prostate cancer.