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PubMed2004

[Imaging update in geriatric oncology].

The cancer is a problem that plagues all the ages but the greater part of the malignant tumors hits the old persons. The more elevated incidence sites of primary tumor in geriatrical age are the prostate, the lung and the colon-rectum in the men and the breast, the colon-rectum, the lung and the stomach in the women. The imaging has made steps of giant in the last few decades, with the introduction of new equipment and methodical news so as to assure everybody early and accurated diagnosis. For the lung carcinoma great advantages have been bring to us with the introduction of CT-PET and the multislice CT, that has concurred the execution of virtual bronchoscopy. The virtual endoscopy has been applied with happening also in the screening of the carcinoma of colon-rectum, executed through CT or MR. New MR technologies have allowed perform spectroscopic studies in such organs as prostate and breast, bringing the biochemical diagnosis beyond that morphologic. The MR then turns out fundamental in the appraisal of the Patient with bone metastases thanks also to the new whole body examinations. Finally the recent technology has allowed the execution of multiorgan CT screening bringing in this way new possibilities but also new questions.

Aged↗
PubMed2005

Virtual colonoscopy.

Virtual colonoscopy (VC) is less invasive than optical colonoscopy in screening for colorectal cancer, although it does require exposure to radiation. Patient sedation is not required, but bowel preparation and air insufflation are. Studies of VC have shown rising detection rates, especially for lesions >or=10mm. Traditional colonoscopy is still required for polyp removal and to confirm cancer.

Clinical Trials as Topic↗
PubMed1989

Evaluation of thyroid calcification using computed radiography with image plate.

The value of lateral magnification soft x-ray roentgenography using a Computed Radiography (CR) system was studied. ROC curve analysis revealed that a CR system has virtually the same, or a better ability than a screen-film system for detecting thyroid calcification. According to our criteria the CR system an accuracy rate of 77.1% in malignant/benign diagnosis was obtained.

Calcinosis↗
PubMed1979

Mutants of Arthroderma benhamiae.

The object of these studies was to isolate conditionally lethal mutants of Arthroderma benhamiae whose vegetative growth was temperature sensitive (ts). Three sorts of mutants were derived from nitrosoguanidine treatment of the microconidia of A. benhamiae: (i) ts "pleomorphic", (ii) ts "non-pleomorphic", and (iii) slow growers (sg) which were not temperature sensitive. The growth of wild type A. benhamiae, as measured by colony diameters, was 6 mm/day at 37 degrees C (chosen as non-permissive for screening mutants) and 5 mm/day at 25 degrees C (chosen as permissive for screening mutants). Growth of mutants of the first sort was virtually stopped at 37 degrees C but their growth at 25 degrees C was more rapid than that of wild type. The colony texture of these mutants was downy and their mycelium sterile. They failed to mate with parents of opposite mating type. These mutants were considered to be ts "pleomorphic". The second sort of mutants were ts "non-pleomorphic". Two isolates of this kind were recovered. They grew normally at 25 degrees C but their growth at 37 degrees C was reduced 50--70% of that of wild type. The nature of the temperature sensitive defect has not been identified. The third sort of mutant occurred very frequently. These isolates were slow growers (sg) regardless of temperature of incubation and their response to the respiratory inhibitors antimycin and salicyl hydroxamic acid suggested a defect in mitochondrial ribosome assembly and deficiencies in cytochromes not unlike those observed in the poky mutants of Neurospora. Two of the sg-mutants (sg 2 and sg3) produced abundant cleistothecia with asci and ascospores when back crossed to parents of opposite mating type. The sg 5 mutant produced cleistothecia but no ascospores. The ergosterol content of the sg 2 mutant was nearly the same as that of wild type while the ergosterol content of sg 3 was somewhat reduced and that of sg 5 was markedly reduced as compared to that of wild type. Thus the ergosterol content seems to play some role in sexual reproduction of A. benhamiae. The pattern of sensitivity to amphotericin B also reflected differences in the sterol content of the mutants, i.e., the two mutants with some alteration in their ergosterol content, sg 3 and sg 5 were more resistant to the antibiotic. During the course of these studies a number of variants were observed that produced different sorts and degrees of pigmentation of the reverse of their colonies. One stable variant of this kind gave rise to colonies with a red reverse when incubated at 37 degrees C and a yellow reverse when incubated at 25 degrees C. When plates were shifted from one temperature to another the next wave of growth was the color specified by the temperature.

Ascomycota↗
PubMed1995

Vaginal thrush and its management in pregnancy.

The frequency of vaginal thrush was determined in an unselected group of patients attending the antenatal clinic. Diagnosis was based on phase-contrast microscopy and culture. One hundred and two patients were initially included but only 98 completed this study. Thrush infection was detected in 25 (25%) patients. All 25 patients underwent treatment with one vaginal ovule containing 400 mg ketoconazole on each of three successive evenings. Thrush attack was eliminated in 23 (92%) cases. In view of the virtual absence of clinical symptoms, the recommendation to undertake general screening for thrush in pregnancy is discussed. The efficacy of treatment with ketoconazole ovules was studied and the results of treatment were reviewed after 4 and 8 weeks. Recurrence or re-infection has to be considered in pregnancy so that thrush treatment should sensibly be undertaken in the third trimester unless subjective symptoms indicate the need for earlier therapy.

Candidiasis, Vulvovaginal↗
PubMedDate not supplied

An areawide cancer reporting network.

A cancer Surveillance Program was formed in 1970 to provide a mechanism for the early identification of some 22,000 cancer cases that are diagnosed annually among the large and varied population of Los Angeles County. The program's rapid reporting procedures facilitate early access to patients for interviewing and specimen collection. Routine review of all reports of microscopically diagnosed malignancies in hospitals throughout the county and screening of all of the county's death certificates provide virtually complete data on cancer incidence in the county. Case reports include information on age, ethnic group, birthplace, residence, religion, marital status, occupation, and industry. Continuing analysis of this information has led to the development of epidemiologic studies of several factors which may have an etiological relationship to human cancer. Among these factors are genetic susceptibility, exposure to air pollutants and industrial carcinogens and possible viral transmission.

California↗
PubMed2001

['Leiden Impotence Screening Test'(LIST) in men with erectile dysfunction as a pre-selective method prior to psychophysiological diagnostic tests].

OBJECTIVE: To compare, in men with erectile dysfunction, the diagnosis obtained with the 'Leiden impotence questionnaire' (LIQ)--which differentiates between psychogenic and organic erectile dysfunction--with the clinical diagnosis based on psychophysiological diagnostic screening (PDS). DESIGN: Exploratory, comparative, and prospective. METHOD: The LIQ-questionnaire was administered to 320 consecutive patients with erectile dysfunction who underwent PDS (i.e. visual sexual stimulation and penile vibration) in the Department of Endocrinology and Reproduction, Erasmus University Medical Centre, Rotterdam, the Netherlands. The clinical diagnosis was based on PDS and later, retrospectively, compared to the LIQ-based diagnosis (only the first six of the 11 LIQ-questions were answered by all patients). RESULTS: The clinical diagnosis, psychogenic or somatic, corresponded well with the LIQ-diagnosis. Following PDS an organic aetiology was assumed in 30% of the patients; compared to 33% according to the LIQ. For a psychogenic aetiology the figures were 70% and 67% respectively. Overall there was a 74% correspondence between PDS-diagnosis and the LIQ-diagnosis. Age was a significant factor: younger men (< 40 years) had the highest LIQ-score (compared to men aged 40-60 and > 60 years) and the strongest penile responses. This is indicative of a more frequent psychogenic aetiology of the erectile dysfunction in younger men. CONCLUSION: Elaborate psychophysiological diagnostic screening is not necessarily the first diagnostic choice in men with erectile dysfunction; one may start by applying the LIQ. A high LIQ-score (5-7) virtually excludes a somatic aetiology. A low LIQ-score (0-2) necessitates further psychosomatic diagnostic screening, preferably with PDS.

Adult↗
PubMed2001

[Individual screening for colorectal cancer: which strategy for which patient?].

Currently, more than 4,000 newly colorectal cancer are diagnosed each year in Belgium. The individual average-risk for developing colorectal cancer is about 5%. 90% of colorectal cancer occurred after the age of 50, and in 70% of the cases in patients without particular risk factors (average-risk population). Personal and/or familial history of colorectal adenoma, colorectal cancer, inflammatory bowel disease localised to the colon, familial polyposis syndrome or Hereditary Non Polyposis Colorectal Cancer (HNPCC) increase the risk of colorectal cancer. An individual appropriate screening of high-risk patients and average-risk asymptomatic patients older than 50, together with endoscopic resection of adenoma decrease the incidence and the mortality of colorectal cancer. Usual screening methods are fecal occult blood testing which is not proven to be efficient alone for individual screening (but still recommended for general population's screening), sigmoidoscopy (which has to be completed by a colonoscopy, if lesions founded), and colonoscopy. Virtual colonoscopy and genetic testing need further evaluation. Currently, colonoscopy seems to be the goldstandard method providing complete examination of the whole colon and being the most cost-effective method. Screening strategy should be decided on an individual basis considering the patient's benefit with respect to the informed consent.

Algorithms↗
PubMed2005

The role of computed tomography in screening for cancer.

Recent technical developments have revolutionized computed tomographic (CT) capabilities, and therefore its clinical applications. Multidetector CT (MDCT) allows scanning of the entire body within a few minutes. Over 60 million CT examinations were performed last year in the United States and Western Europe. Many emergency room physicians use it as a virtual physical examination. Its applications to early cancer detection have been controversial. Targeted CT screening for widely prevalent cancers, namely lung and colon, has been advocated in the literature. Combining the two, a whole-body screening CT scan might be offered to appropriately selected, high-risk populations.

Colorectal Neoplasms↗
PubMed2002

Successful colorectal cancer screening starts with primary care.

Colorectal cancer screening is effective. Screening rates remain low, but that will change. All guidelines now recommend colorectal cancer screening, the value of screening is being promoted in the popular media, and insurers are beginning to pay for screening tests. For screening programs to be successful, good intentions must be backed by reminder systems, readily available patient information, and other changes in office practice. Currently recommended screening options accommodate a broad range of patient preferences and save lives, but none is ideal. Newer tests, such as virtual colonoscopy and stool-based DNA tests, will help if they offer greater sensitivity, specificity, or patient acceptability than current screening options.

Barium Sulfate↗
PubMed1986

Immunofluorescent screening of monoclonal antibodies to surface antigens of animal and plant cells bound to polycarbonate membranes.

We have developed an immunofluorescent screening method in which animal or plant cells are immobilized without fixation on polycarbonate (Nuclepore) membranes. The technique does not involve centrifugation, and virtually no cells are lost during processing. Direct microscopic analysis of antibody binding provides an extremely sensitive and reproducible screening system for hybridoma supernatants.

Animals↗
PubMedDate not supplied

Current trends in screening and secondary prevention of colorectal cancer.

Colorectal cancer is one of the most frequent neoplasms in Western countries with an estimated 400,000 deaths per year worldwide. Several randomized studies have demonstrated that screening programs with FOBT (Fecal Occult Blood Test) reduce mortality from 18 to 33%, whereas case-control and cohort studies with endoscopy have shown a mortality reduction ranging from 60 to 76%. The target population for secondary prevention is men and women aged more than 50 years and younger subjects in case first-degree relatives are affected or the family pedigree raises the suspicion of a genetic syndrome. This report summarizes the results of different screening strategies for average risk patients (FOBT, anamnestic risk questionnaire, sigmoidoscopy, colonoscopy and virtual colonoscopy) and the surveillance protocols applicable to high-risk patients, particularly for hereditary syndromes such as HNPCC and FAP.

Colonography, Computed Tomographic↗
PubMed1997

Virtual colonoscopy with magnetic resonance imaging: in vitro evaluation of a new concept.

BACKGROUND & AIMS: Screening for colonic polyps is desirable. A new concept based on cross-sectional and endoscopic analysis of a magnetic resonance (MR) data set is presented. METHODS: Ex vivo autopsy colonic specimens, containing artificially placed polyps, were obtained and filled with a gadolinium-containing solution. Forty-four thin-section MR images were obtained in a 1.5-T MR scanner in 28 seconds. A three-dimensional endoscopic fly-through of these images was rendered. Fly-throughs and two-dimensional cross-sectional images were analyzed by two observers for the presence of polyps. RESULTS: The average sensitivity and specificity for the detection of polyps based on three-dimensional endoscopic MR colon imaging were 87% and 96%, respectively. Analysis of cross-sectional images showed an overall sensitivity and specificity of merely 57% and 84%, respectively. The difference in the interpretation of three-dimensional MR colonoscopy and two-dimensional cross-sections was statistically significant (P < 0.001). With three-dimensional MR colonoscopy, overall sensitivity for detection of polyps measuring < or =5 mm in length and diameter was 70%; for larger polyps, it increased to 95% (P < 0.01). CONCLUSIONS: The feasibility of an MR-based endoluminal assessment of the colon is shown. Minimal invasiveness, lack of radiation exposure, and high in vitro diagnostic accuracy warrant further investigation of this novel concept.

Colonic Polyps↗
PubMed1987

Marijuana testing--how good is it?

Testing for the use of marijuana necessitates one or more levels of assessment, depending on the clinical application of the test results. The EMIT-dau screening test with a sensitivity limit of 20 ng/ml is highly satisfactory for screening for the absence of marijuana in the urine. This test has a virtual 100% true-negative rate as long as an unadulterated urine specimen is analyzed. Positive results by the EMIT-dau procedure are presumptive because the test seems to produce false-positive results when applied to a random population of suspected drug users. In a population in a specific clinical environment such as in drug-treatment programs in which 20 of every 100 specimens will yield positive THC-COOH results by EMIT-dau screening, 3 (15%) of the 20 positive results will likely be false-positive. Our experience with the EMIT-dau suggests that of 100 test results, 3 will be false-positive, an overall 3% false-positive rate. If a positive test result will put the patient in considerable jeopardy and the screening result is the only evidence of drug use, confirmatory testing is imperative. Of the confirmatory tests, GC/MS seems to have the specificity necessary to provide a high level of confidence in the results. A combination of the EMIT procedure with a sensitivity level of 20 ng/ml and GC/MS confirmation yields virtually 100% accuracy in detection of marijuana abuse.

Cannabinoids↗
PubMed1990

Diagnostic imaging evaluation of benign prostatic hyperplasia.

The optimal evaluation of the patient with symptomatic BPH should include the diagnostic testing necessary to supplement the clinical examination and select a suitable medical, surgical, or interventional therapeutic option. A variety of imaging modalities offer unique but often unnecessary, superfluous, or very expensive information. Rarely is therapeutic intervention for symptomatic BPH denied a patient because of lesions detected with screening imaging tests; it may be only delayed rather than withheld. Virtually all pretreatment IVUs in patients with BPH are normal. Estimates range from 73 to 93 per cent of the studies as normal or having only insignificant findings. Significant pathology, either life-threatening or sufficient to alter or delay treatment, is found between 0.5 and 10 per cent of the time. Upper tract hydronephrosis is the most common finding (3 to 13 per cent). Renal or urothelial cancer prevalence in the patient population with BPH is really no different than in the general population. If signs or symptoms are not present to alert the clinician to some risk factor other than the symptoms of BPH, there is no benefit for routine urography solely for upper tract cancer detection. Furthermore, with the growing use of nonionic contrast media for elderly patients, the cost of the preoperative routine IVU will increase even further as the added charge for contrast ($100 or more) is tacked onto the cost of the study. Azotemic patients are best served by diagnostic ultrasound or by Foley catheter drainage prior to urography when indicated. Ultrasound remains an operator-dependent and technology-limited examination that cannot measure renal function, but the sensitivity and specificity, as well as the overall diagnostic accuracy, are equal to or greater than those of urography for the detection of hydronephrosis, cystic renal masses, and bladder or prostate abnormalities. False-positive ultrasound scans do occur secondary to reflux caused by bladder diverticula, megacalicosis, or other congenital abnormalities. However, these lesions are distinctly rare. Sensitivity for urothelial malignancy is not good, but endoscopic, clinical, and laboratory evaluations should provide adequate pretherapy diagnostic screening. In spite of the preoperative comfort that a normal IVU may give the patient and the operating surgeon, routine intravenous urography for all BPH patients should no longer be considered necessary. Diagnostic ultrasound, either transabdominal or transrectal, also offers the ability to evaluate the kidneys, ureters, and bladder, effectively replacing routine intravenous urography.(ABSTRACT TRUNCATED AT 400 WORDS)

Humans↗
PubMedDate not supplied

Virtual endoscopy: development and evaluation using the Visible Human datasets.

Virtual endoscopy (VE) is a new method of diagnosis using computer processing of 3D image datasets (such as CT or MRI scans) to provide simulated visualizations of patient specific organs similar or equivalent to those produced by standard endoscopic procedures. Conventional endoscopy is invasive and often uncomfortable for patients. It sometimes has serious side effects such as perforation, infection and hemorrhage. VE visualization avoids these risks and can minimize difficulties and decrease morbidity when used before actual endoscopic procedures. In addition, there are many body regions not compatible with real endoscopy that can be explored with VE. Eventually, VE may replace many forms of real endoscopy. There remains a critical need to refine and validate VE visualizations for routine clinical use. We have used the Visible Human Dataset from the National Library of Medicine to develop and test these procedures and to evaluate their use in a variety of clinical applications. We have developed specific clinical protocols to compare virtual endoscopy with real endoscopy. We have developed informative and dynamic on-screen navigation guides to help the surgeon or physician interactively determine body orientation and precise anatomical localization while performing the VE procedures. Additionally, the adjunctive value of full 3D imaging (e.g. looking "outside" of the normal field of view) during the VE exam is being evaluated. Quantitative analyses of local geometric and densitometric properties obtained from the virtual procedures ("virtual biopsy") are being developed and compared with other direct measures. Preliminary results suggest that these virtual procedures can provide accurate, reproducible and clinically useful visualizations and measurements. These studies will help drive improvements in and lend credibility to VE procedures and simulations as routine clinical tools. VE holds significant promise for optimizing endoscopic diagnostic procedures, minimizing patient risk and morbidity, and reducing health care costs.

Anatomy, Cross-Sectional↗
PubMed2004

G protein-coupled receptors: in silico drug discovery in 3D.

The application of structure-based in silico methods to drug discovery is still considered a major challenge, especially when the x-ray structure of the target protein is unknown. Such is the case with human G protein-coupled receptors (GPCRs), one of the most important families of drug targets, where in the absence of x-ray structures, one has to rely on in silico 3D models. We report repeated success in using ab initio in silico GPCR models, generated by the predict method, for blind in silico screening when applied to a set of five different GPCR drug targets. More than 100,000 compounds were typically screened in silico for each target, leading to a selection of <100 "virtual hit" compounds to be tested in the lab. In vitro binding assays of the selected compounds confirm high hit rates, of 12-21% (full dose-response curves, Ki < 5 microM). In most cases, the best hit was a novel compound (New Chemical Entity) in the 1- to 100-nM range, with very promising pharmacological properties, as measured by a variety of in vitro and in vivo assays. These assays validated the quality of the hits as lead compounds for drug discovery. The results demonstrate the usefulness and robustness of ab initio in silico 3D models and of in silico screening for GPCR drug discovery.

Algorithms↗
PubMed2004

Understanding why women decline HIV testing.

BACKGROUND: The Department of Health (DH) set a target for HIV testing--uptake should be at least 90% by 31 December 2002 (Department of midwife Health, 2000), i the number of 80% decrease in n order to see a babies born with HIV (Tookey et al, 2002). As an exercise to measure Newham Healthcare Trust against this standard and review the antenatal care HIV-positive women received, the maternity unit undertook an audit. One in 160 pregnant women receiving antenatal care in the London Borough of Newham are HIV positive (Communicable Disease Screening Centre, 2003), according to the HIV anonymous screening programme, however the rate of transmission to the baby is virtually zero, when babies were followed up at birth, six months and one year Healthcare NH S Trust, 2003). Newham's HIV testing uptake ranges from 80% to 90% (with an average of 88%). A strategy for improving the uptake has been to explore why the 10% to 20% of women decline testing; hence the Trust underwent an audit to explore the reasons women gave when they declined testing. Audit findings Some 2138 forms were returned over a seven-month period, of which 328 (15%) were from women who declined HIV testing. Uptake within that period ranged from 74% to 90%. Ten new positive women were identified. The HIV-specialist midwife carries a caseload and is aware of all positive women, therefore was able to identify the new cases. The reasons given for decline ranged from cultural and religious beliefs to those who said they were not at risk. Practice implications Where women are aware of their HIV status, services can be put in place to support them through their pregnancy and life as a positive parent, equally important is the ability to minimise the risk of transmission to babies, therefore it is vital that women understand the purpose of early diagnosis through testing and its consequences. Midwives have a vital role to play in ensuring pregnant women receive adequate information to form their decision. If a woman chooses not to have the test, midwives should explore her reasons without prejudice. It is also recommended that women who decline testing are reoffered the HIV test at their subsequent antenatal visit, allowing them the opportunity to digest the information and discuss it with a partner. The purpose of the audit was to assess how the Trust would meet the DH target (90% uptake), as part of a review of the maternity HIV service.

AIDS Serodiagnosis↗