Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 55
Filter
1.
Ann Dermatol Venereol ; 151(2): 103248, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38513422

ABSTRACT

BACKGROUND: There are long patient waiting lists for specialist care. A dermatology dialogue service between primary and secondary care (DDPS) was developed in eastern England. Primary care referrers uploaded patient images of skin conditions for review by and dialogue with consultant dermatologists in an attempt to retain patients in primary care rather than refer them to secondary care. METHODS: Evaluation of service performance against specific targets, including reduction in secondary care waiting list growth over the period April 2021-March 2022 inclusive. Service activity was summarized in terms of speed of resolution, case numbers, and dispositions. Clinician and patient satisfaction were assessed using structured questionnaires. Actual numbers of new referrals were compared to projections based on historical data. Waiting list growth was compared to other specialties and other commissioning areas. Waiting times to initial treatment were monitored. RESULTS: Over 3300 patients were enrolled and > 90% of dialogues were resolved within 36 hours. Clinician and patient satisfaction were high. Frequently asked questions and conditions were highlighted by dermatologists to design and deliver an educational event for primary care clinicians that was well received. Waiting list growth for dermatology patients in the commissioning area was smaller than for other major specialties, and generally smaller than growth for dermatology waiting lists commissioned by other NHS commissioners. There was no negative impact on the urgent priority (cancer pathway) waiting list. CONCLUSION: The DDPS was satisfactory for clinicians and patients and coincided with lower growth in dermatology waiting lists than might otherwise have been expected.


Subject(s)
Dermatology , Patient Satisfaction , Primary Health Care , Referral and Consultation , Secondary Care , Waiting Lists , Humans , England , Skin Diseases/therapy , Surveys and Questionnaires
2.
Rev Epidemiol Sante Publique ; 68(2): 99-107, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32037129

ABSTRACT

BACKGROUND: Concern about health misinformation is longstanding, especially on the Internet. METHODS: Using agent-based models, we considered the effects of such misinformation on a norovirus outbreak, and some methods for countering the possible impacts of "good" and "bad" health advice. The work explicitly models spread of physical disease and information (both online and offline) as two separate but interacting processes. The models have multiple stochastic elements; repeat model runs were made to identify parameter values that most consistently produced the desired target baseline scenario. Next, parameters were found that most consistently led to a scenario when outbreak severity was clearly made worse by circulating poor quality disease prevention advice. Strategies to counter "fake" health news were tested. RESULTS: Reducing bad advice to 30% of total information or making at least 30% of people fully resistant to believing in and sharing bad health advice were effective thresholds to counteract the negative impacts of bad advice during a norovirus outbreak. CONCLUSION: How feasible it is to achieve these targets within communication networks (online and offline) should be explored.


Subject(s)
Caliciviridae Infections/epidemiology , Communication , Disease Outbreaks , Health Literacy , Internet , Norovirus/physiology , Systems Analysis , Access to Information , Caliciviridae Infections/transmission , Caliciviridae Infections/virology , Consumer Health Information/organization & administration , Consumer Health Information/standards , Consumer Health Information/statistics & numerical data , Health Literacy/organization & administration , Health Literacy/standards , Health Literacy/statistics & numerical data , Humans , Information Dissemination , Information Services/organization & administration , Information Services/standards , Public Reporting of Healthcare Data
3.
Endoscopy ; 42(10): 800-5, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20821361

ABSTRACT

BACKGROUND AND STUDY AIMS: Periodic surveillance with systematic biopsies is recommended for patients with Barrett's esophagus. Brush cytology has been proposed as a simple inexpensive component of endoscopic surveillance, which may also detect abnormalities prior to detection of histologic abnormalities. The aim of the current study was to determine whether brush cytology provides any additional value over endoscopic surveillance biopsies in patients with Barrett's esophagus. PATIENTS: This retrospective cohort study included 530 patients with Barrett's esophagus undergoing endoscopic surveillance with paired biopsy and cytology specimens at the Cleveland Clinic between January 1994 and July 2008. The main outcome measures were sensitivity, specificity, and concordance rates of cytology and histology. RESULTS: Sensitivity of cytology for any dysplasia was 49 % and specificity was 95 %. However, sensitivity was 82 % for detection of high grade dysplasia/adenocarcinoma but only 31 % for low grade/indefinite for dysplasia. The concordance rate between cytology and histology was 80 %. Histology had a higher dysplasia detection rate than cytology (24.0 % vs. 15.7 %, respectively; P <0.0001). CONCLUSIONS: Cytology has excellent specificity and good sensitivity for the detection of high grade dysplasia/adenocarcinoma but poor sensitivity for low grade dysplasia. There was substantial concordance between cytology and histology for the detection of dysplasia. However, histology had a higher dysplasia detection rate and therefore the value of routine cytology in the surveillance of Barrett's esophagus is questionable.


Subject(s)
Adenocarcinoma/pathology , Barrett Esophagus/pathology , Biopsy/methods , Cytodiagnosis/methods , Esophageal Neoplasms/pathology , Precancerous Conditions/pathology , Aged , Cohort Studies , Disease Progression , Endoscopy , Female , Humans , Male , Middle Aged , Retrospective Studies , Sensitivity and Specificity
4.
Oncogene ; 26(42): 6238-43, 2007 Sep 13.
Article in English | MEDLINE | ID: mdl-17369840

ABSTRACT

The management of pain and morbidity due to the spreading and growth of cancer within bone remains to be a paramount problem in clinical care. Cancer cells actively transform bone, however, the molecular requirements and mechanisms of this process remain unclear. This study shows that functional modulation of the alphavbeta3 integrin receptor in prostate cancer cells is required for progression within bone and determines tumor-induced bone tissue transformation. Using histology and quantitative microCT analysis, we show that alphavbeta3 integrin is required not only for tumor growth within the bone but for tumor-induced bone gain, a response resembling bone lesions in prostate cancer patients. Expression of normal, fully functional alphavbeta3 enabled tumor growth in bone (incidence: 4/4), whereas alphavbeta3 (-), inactive or constitutively active mutants of alphavbeta3 did not (incidence: 0/4, 0/6 and 1/7, respectively) within a 35-day-period. This response appeared to be bone-specific in comparison to the subcutis where tumor incidence was greater than 60% for all groups. Interestingly, bone residing prostate cancer cells expressing normal or dis-regulated alphavbeta3 (either inactive of constitutively active), but not those lacking beta3 promoted bone gain or afforded protection from bone loss in the presence or absence of histologically detectable tumor 35 days following implantation. As bone is replete with ligands for beta3 integrin, we next demonstrated that alphavbeta3 integrin activation on tumor cells is essential for the recognition of key bone-specific matrix proteins. As a result, prostate cancer cells expressing fully functional but not dis-regulated alphavbeta3 integrin are able to control their own adherence and migration to bone matrix, functions that facilitate tumor growth and control bone lesion development.


Subject(s)
Bone Neoplasms/pathology , Bone Neoplasms/secondary , Bone Remodeling/physiology , Bone and Bones/pathology , Integrin alphaVbeta3/physiology , Prostatic Neoplasms/metabolism , Animals , Cell Line, Tumor , Female , Humans , Integrin alphaVbeta3/biosynthesis , Integrin alphaVbeta3/genetics , Male , Mice , Mice, Inbred NOD , Mice, SCID , Prostatic Neoplasms/pathology , Vitronectin/metabolism
5.
Int J Gynecol Cancer ; 16(5): 1815-22, 2006.
Article in English | MEDLINE | ID: mdl-17009977

ABSTRACT

The purpose of this study was to determine the sensitivity and specificity of optical coherence tomography (OCT) under two well-defined clinical settings. First, as an aid to cervical cancer screening, using visual inspection with acetic acid (VIA) in low-resource settings, and the second, as an adjunct to the traditional management of abnormal cervical cytology with colposcopy and biopsy. Patients referred for colposcopy with > or = atypical squamous cells of undetermined significance were accrued for the study. Each subject underwent VIA and colposcopy. OCT was performed in all VIA- and colposcopy-positive areas and at the squamocolumnar junction in all four quadrants. The sensitivity of VIA for > or = cervical intraepithelial neoplasia 2 was 76% (95% CI 58-88). When OCT was applied to VIA as a secondary screen, the specificity improved from 34% (95% CI 27-41) to 61% (95% CI 60-74). With liberal diagnostic criteria for the majority of the colposcopy examinations, OCT showed an even greater relative improvement in specificity. OCT proved to be a fair diagnostic modality (receiver operating characteristic curve 0.73) adjunctive to VIA and colposcopy. On the basis of the above findings, we believe that this technology could potentially show greatest utility in the management of cervical dysplasia in low-resource settings where a single episode of care is most desirable.


Subject(s)
Colposcopy/methods , Tomography, Optical Coherence , Uterine Cervical Dysplasia/diagnosis , Uterine Cervical Neoplasms/diagnosis , Adolescent , Adult , Aged , Cervix Uteri/pathology , Female , Humans , Middle Aged , Sensitivity and Specificity
6.
Histopathology ; 41(1): 35-41, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12121235

ABSTRACT

AIMS: Keratin 903 (also known as anti-cytokeratin antibody 34betaE12) is widely used to differentiate benign glands from malignant glands in prostate needle biopsies. However, it is subject to considerable staining heterogeneity. We sought to evaluate the use of cytokeratin 5/6 (CK5/6) as an effective alternative to K903 in the evaluation of prostate needle biopsies in clinical practice. METHODS AND RESULTS: Thirty Hollandes-fixed prostate needle biopsies were randomly selected over a period of 2 months from the surgical specimens accessioned over that period of time. Twelve cases had diagnosed prostatic adenocarcinoma (Gleason scores 3 + 3, 3 + 4 and 4 + 4) and the remaining cases (n = 18) were negative for carcinoma. Four sequential sections were stained with H&E (x2), K903, and CK5/6. Care was taken to preserve tissue so that matching glands were evaluated on all four sections. All cases were run routinely over a period of 3 weeks on a daily basis with matching positive controls. All slides were evaluated in a blinded fashion independently by two pathologists using a semiquantitative analysis of staining: <25%, 25-50%, 50-75%, >75% and >95% of benign glands (verified on H&E). Cases that showed no staining were repeated to ensure no false negatives. Both observers agreed with respect to percentage of staining in 96% of the cases. Twenty-nine of 30 cases (97%) showed staining in >95% of benign glands with CK5/6. In contrast, K903 staining was seen in <50% of benign glands in five of 30 (17%), 50-75% in nine of 30 (30%), and >75% in 10 of 30 (33%), with only two cases (7%) showing >95% staining for K903. In four cases (13%) the K903 failed to stain any tissue even after repeat staining. K903 was conspicuously negative in atrophic glands in three of 30 cases (10%). Neither K903 nor CK5/6 stained malignant glands. Using a cut-off of >75% staining in benign glands the sensitivity of CK5/6 and K903 was 97% and 40%, respectively. CONCLUSIONS: CK5/6 has superior sensitivity and reliability compared with that of K903 when evaluating routine prostate needle biopsies, including improved staining of atrophic prostatic glands. While K903 is traditionally used to differentiate benign glands from malignant glands, these results support the use of CK5/6 as an effective and reliable substitute for K903 in routine clinical practice.


Subject(s)
Adenocarcinoma/diagnosis , Biomarkers, Tumor , Keratins/metabolism , Prostate/metabolism , Prostatic Neoplasms/diagnosis , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Antibodies, Monoclonal , Biopsy, Needle , Diagnosis, Differential , Humans , Immunoenzyme Techniques , Keratins/immunology , Male , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Reproducibility of Results
7.
Biotechnol Bioeng ; 76(3): 241-6, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11668460

ABSTRACT

Remarkable increases in enzyme catalytic stability resulting from addition of charged water-soluble polymers have recently been reported, suggesting that use of these polymers may be an attractive general strategy for enzyme stabilization. To test the proposed hypothesis that coulombic forces between water-soluble polymers and enzymes are primarily responsible for enzyme stabilization, we examined the catalytic stability and activity of two enzymes in the presence of polymers differing in net charge. All polymers tested increased enzyme lifetimes, regardless of their net charge, suggesting that stabilization of these enzymes by water-soluble polymers is not solely dependent on simple electrostatic interactions between the polymers and enzymes.


Subject(s)
Acrylic Resins/pharmacology , Alcohol Dehydrogenase/metabolism , Enzyme Stability/drug effects , Polyethyleneimine/pharmacology , Saccharomyces cerevisiae/enzymology , Subtilisins/metabolism , Alcohol Dehydrogenase/drug effects , Solubility , Water/chemistry
8.
Obstet Gynecol ; 98(4): 634-7, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11576580

ABSTRACT

OBJECTIVE: To examine the histology of the vaginal wall in women with an enterocele confirmed by physical examination, cystoproctography, and intraoperative exploration. METHODS: Thirteen women with posthysterectomy apical and posterior wall prolapse were evaluated with a detailed physical examination, cystoproctography, and intraoperative exploration. All women had enterocele repair. A specimen of full thickness vaginal wall from the leading edge of the enterocele was excised and examined histologically. The histology of these patients was compared with the histology of two comparison groups, five women undergoing hysterectomy without prolapse and 13 women undergoing radical hysterectomy. RESULTS: One woman with an enterocele repaired intraoperatively did not have an enterocele by cystoproctography. One woman with an enterocele repaired intraoperatively did not have an enterocele detected by physical examination. All women with an enterocele repaired had an intact vaginal wall muscularis. No woman had vaginal wall epithelium in direct contact with the peritoneum. The average vaginal wall muscularis thickness in women with enteroceles was 3.5 +/- 1.4 mm, in women with no prolapse 3.2 +/- 0.8 mm, and in women undergoing radical hysterectomy 2.8 +/- 0.9 mm. CONCLUSION: Women with enteroceles have a well-defined vaginal muscularis between the peritoneum and vaginal epithelium.


Subject(s)
Intestinal Diseases/pathology , Uterine Prolapse/pathology , Vagina/pathology , Aged , Analysis of Variance , Female , Hernia/diagnostic imaging , Hernia/pathology , Humans , Intestinal Diseases/diagnostic imaging , Middle Aged , Radiography , Uterine Prolapse/diagnostic imaging
9.
Am J Surg Pathol ; 24(4): 543-52, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10757401

ABSTRACT

A series of 35 cases of Paget's disease (PD) of the vulva and perianal area were studied to characterize the spectrum of proliferative epidermal lesions that occur in this rare disease but generally have been overlooked. The study group consisted of 8 men and 27 women with a median age of 66 years. Nineteen patients (54%) had one or more benign proliferative epidermal lesions, including 7 of 22 patients (32%) with vulvar PD and 12 of 13 patients (92%) with perianal PD. Two patients also had malignant squamous cell neoplasms. Three categories of epidermal hyperplasia were identified: (1) squamous hyperplasia NOS (34%), (2) fibroepithelioma-like hyperplasia (32%), and (3) papillomatous hyperplasia (29%). Small nests of hyperplastic squamous cells protruding into the dermis simulated microinvasive squamous carcinoma in three of these cases. None of the nine papillomatous hyperplasias tested for HPV by in-situ hybridization were positive. The squamous hyperplasia NOS and the papillomatous hyperplasia did not show a predilection for an anatomic site. In contrast, fibroepithelioma-like hyperplasia occurred in 69% of perianal PD compared with only 9% of vulvar cases. There was no association between the type of epidermal hyperplasia and the presence of a regional internal cancer. Two patients with vulvar PD had malignant squamous lesions, including one with squamous cell carcinoma in-situ (CIS) of classic type and one patient with invasive squamous cell carcinoma (InvSCC); the latter also had invasive PD. The malignant squamous component in both patients was positive for HPV 16/18, whereas the associated Paget's cells were HPV-negative. The finding of fibroepithelioma-like hyperplasia in the anogenital skin should prompt a thorough search for Paget' s cells. Papillomatous hyperplasia may be misinterpreted as condyloma acuminatum when Paget's cells are few in number and have koilocytotic-like vacuolar change or for warty (condylomatous) carcinoma when pseudoinvasive foci are present. When Paget's cells are florid and diffusely infiltrate an acanthotic epidermis, classic CIS may be misdiagnosed. Cytokeratin 7 immunostain is an excellent marker for intraepithelial and invasive Paget's cells that aids in their distinction from hyperplastic and malignant squamous cells.


Subject(s)
Anal Canal/pathology , Epidermis/pathology , Paget Disease, Extramammary/pathology , Skin Neoplasms/pathology , Vulva/pathology , Aged , Aged, 80 and over , Carcinoma in Situ/pathology , Carcinoma, Squamous Cell/pathology , DNA, Viral/analysis , Diagnosis, Differential , Female , Humans , Hyperplasia , In Situ Hybridization , Male , Middle Aged , Papillomaviridae/isolation & purification
12.
Bioorg Med Chem ; 7(10): 2175-81, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10579523

ABSTRACT

Haloalkane dehalogenase (Dh1A) from Xanthobacter autotrophicus GJ10 catalyzes the dehalogenation of short chain primary alkyl halides. Due to the high Km and low turnover, wild type Dh1A is not optimal for applications in bioremediation. We have developed an in vivo screen, based on a colorimetric pH indicator, to identify Dh1A mutant with improved catalytic activity. After screening 50,000 colonies, we identified a Dh1A mutant with a lower pH optimum. Sequence analysis of the mutant revealed a single substitution, alanine 149 to threonine, which is located close to the active site of Dh1A. Replacement of alanine 149 via site-directed mutagenesis with threonine, serine or cysteine retained the mutant phenotype. Other substitutions at position 149 show little or no activity.


Subject(s)
Hydrolases/genetics , Mutation , Protein Engineering/methods , Escherichia coli/genetics , Ethylene Dichlorides/metabolism , Gene Expression Regulation, Bacterial , Gene Library , Hydrolases/metabolism , Kinetics , Mutagenesis , Mutagenesis, Site-Directed , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Reproducibility of Results
13.
Biochemistry ; 38(18): 5772-8, 1999 May 04.
Article in English | MEDLINE | ID: mdl-10231528

ABSTRACT

The substrate specificities and product inhibition patterns of haloalkane dehalogenases from Xanthobacter autotrophicus GJ10 (XaDHL) and Rhodococcus rhodochrous (RrDHL) have been compared using a pH-indicator dye assay. In contrast to XaDHL, RrDHL is efficient toward secondary alkyl halides. Using steady-state kinetics, we have shown that halides are uncompetitive inhibitors of XaDHL with 1, 2-dichloroethane as the varied substrate at pH 8.2 (Cl-, Kii = 19 +/- 0.91; Br-, Kii = 2.5 +/- 0.19 mM; I-, Kii = 4.1 +/- 0.43 mM). Because they are uncompetitive with the substrate, halide ions do not bind to the free form of the enzyme; therefore, halide ions cannot be the last product released from the enzyme. The Kii for chloride was pH dependent and decreased more than 20-fold from 61 mM at pH 8.9 to 2.9 mM at pH 6.5. The pH dependence of 1/Kii showed simple titration behavior that fit to a pKa of approximately 7.5. The kcat was maximal at pH 8.2 and decreased at lower pH. A titration of kcat versus pH also fits to a pKa of approximately 7.5. Taken together, these data suggest that chloride binding and kcat are affected by the same ionizable group, likely the imidazole of a histidyl residue. In contrast, halides do not inhibit RrDHL. The Rhodococcus enzyme does not contain a tryptophan corresponding to W175 of XaDHL, which has been implicated in halide ion binding. The site-directed mutants W175F and W175Y of XaDHL were prepared and tested for halide ion inhibition. Halides do not inhibit either W175F or W175Y XaDHL.


Subject(s)
Chlorides/chemistry , Hydrolases/antagonists & inhibitors , Hydrolases/chemistry , Amino Acid Sequence , Binding, Competitive , Chlorides/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Ethylene Chlorohydrin/chemistry , Ethylene Chlorohydrin/pharmacology , Gram-Negative Aerobic Bacteria/enzymology , Hydrogen-Ion Concentration , Indicators and Reagents , Kinetics , Molecular Sequence Data , Mutagenesis, Site-Directed , Nitrophenols , Phenolsulfonphthalein/analogs & derivatives , Phenylalanine/genetics , Rhodococcus/enzymology , Substrate Specificity , Tryptophan/genetics , Tyrosine/genetics
14.
Am J Surg Pathol ; 22(8): 965-75, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9706976

ABSTRACT

A series of 12 adenoid basal carcinomas and three adenoid basal hyperplasias of the cervix were analyzed. The ages of the patients with adenoid basal carcinoma ranged from 30 to 91 years with a mean of 71 years. Pap smear results for 11 of 12 (92%) were abnormal. Almost all patients were asymptomatic. None had a gross cervical tumor. All tumors had typical histologic features of adenoid basal carcinoma, with various degrees of squamous differentiation. Depth of tumor invasion ranged from 2 mm to 10 mm (mean, 4.3 mm; median, 3.7 mm), exceeding 3 mm in six tumors (50%). Tumor volume was >500 mm3 in four tumors (33%). An associated neoplastic squamous lesion was present in 92% of patients, including high-grade cervical intraepithelial neoplasia in 10 cases and microinvasive squamous cell carcinoma in one. Treatment was predominantly surgical, usually after some form of cervical conization; conization alone was performed in three patients. Lymph nodes were removed in five patients; none of 104 nodes had metastases. No recurrence of tumor developed in any patient. Nine patients were alive without disease after 4 to 82 months (mean, 30 months), and three died without disease after 24, 63, and 87 months. The three patients with adenoid basal hyperplasia also were asymptomatic and did not have a gross cervical lesion. Pap smear results for two patients were abnormal. The adenoid basal hyperplasias were incidental, very superficial lesions that resembled small adenoid basal carcinomas. Generally, they were attached to the squamous or endocervical mucosal epithelium; all were less than 0.5 mm in depth. Treatment was hysterectomy in one patient and conization in two. Follow-up was short but uneventful. Our findings, together with those previously reported, indicate (1) adenoid basal carcinoma with typical histologic features is not a malignant neoplasm in that it typically presents in asymptomatic women, usually is discovered after an abnormal Pap smear result due to cervical intraepithelial neoplasia, does not produce a grossly visible lesion, has never metastasized to regional lymph nodes or elsewhere, and has never itself caused death; (2) rare, histologically atypical tumors with distinctly malignant features should not be regarded as adenoid basal carcinoma; and (3) adenoid basal hyperplasia probably is a small adenoid basal carcinoma. We propose the term "adenoid basal epithelioma" to replace adenoid basal carcinoma and adenoid basal hyperplasia, because it better describes the clinicopathologic features of these distinctive lesions and their excellent prognosis and may reduce the likelihood of unnecessarily aggressive treatment.


Subject(s)
Carcinoma, Basal Cell/pathology , Cervix Uteri/pathology , Uterine Cervical Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Carcinoma, Basal Cell/surgery , Conization , Fallopian Tubes/surgery , Female , Follow-Up Studies , Humans , Hyperplasia , Hysterectomy , Lymph Node Excision , Metaplasia , Middle Aged , Neoplasm Invasiveness/pathology , Ovariectomy , Treatment Outcome , Uterine Cervical Neoplasms/surgery
15.
Risk Anal ; 17(5): 625-33, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9404052

ABSTRACT

This paper provides an illustration of how a geographic information system (GIS) can be used in risk analysis. It focuses on liquid hazardous waste transport and utilizes records archived by the London Waste Regulatory Authority. This data source provides information on the origin and destination of each waste stream, but not the route followed during transport. A GIS was therefore employed to predict the paths used, taking into account different routing criteria and characteristics of the available road network. Details were also assembled on population distribution and ground-water vulnerability, thus providing a basis for evaluating the potential consequences of a waste spillage during transport. Four routing scenarios were implemented to identify sections of road which consistently saw heavy traffic. These simulations also highlighted that some interventions could lead to risk tradeoffs rather than hazard mitigation. Many parts of the research would not have been possible without a GIS, and the study demonstrates the considerable potential of such software in environmental risk assessment and management.


Subject(s)
Hazardous Waste/adverse effects , England , Environmental Health , Hazardous Waste/analysis , Humans , Information Systems , Risk Assessment , Risk Factors , Transportation , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
16.
Biotechnol Bioeng ; 55(1): 163-9, 1997 Jul 05.
Article in English | MEDLINE | ID: mdl-18636454

ABSTRACT

Paint stripping wastes generated during the decontamination and decommissioning of former nuclear facilities contain paint stripping organics (dichloromethane, 2-propanol, and methanol) and bulk materials containing paint pigments. It is desirable to degrade the organic residues as part of an integrated chemical-biological treatment system. We have developed a modified gas lift loop bioreactor employing a defined consortium of Rhodococcus rhodochrous strain OFS and Hyphomicrobium sp. DM-2 that degrades paint stripper organics. Mass transfer coefficients and kinetic constants for biodegradation in the system were determined. It was found that transfer of organic substrates from surrogate waste into the air and further into the liquid medium in the bioreactor were rapid processes, occurring within minutes. Monod kinetics was employed to model the biodegradation of paint stripping organics. Analysis of the bioreactor process was accomplished with BIOLAB, a mathematical code that simulates coupled mass transfer and biodegradation processes. This code was used to fit experimental data to Monod kinetics and to determine kinetic parameters. The BIOLAB code was also employed to compare activities in the bioreactor of individual microbial cultures to the activities of combined cultures in the bioreactor. This code is of benefit for further optimization and scale-up of the bioreactor for treatment of paint stripping and other volatile organic wastes in bulk materials.

17.
Arch Pathol Lab Med ; 121(5): 481-4, 1997 May.
Article in English | MEDLINE | ID: mdl-9167601

ABSTRACT

OBJECTIVE: Use of the image-guided stereotactic brain biopsy has facilitated the diagnosis of previously inaccessible lesions with both safety and reliability. However, few studies have assessed the diagnostic yield of frozen section evaluation of the initial stereotactic target (FS-0). We describe our experience with 188 stereotactic brain biopsies in order to evaluate the diagnostic yield of FS-0. DESIGN: Retrospective study of 188 stereotactic brain biopsies from 185 patients. SETTING: Tertiary referral center with a high volume of neurosurgical cases including image-guided stereotactic brain biopsies. PATIENTS: One hundred eighty-five patients who underwent imaged-guided stereotactic brain biopsy over a 58-month period. RESULTS: The patients studied included 107 males and 78 females (mean age 48 years). Eleven (6%) biopsies were nondiagnostic. Diagnoses from FS-0 included a neoplastic condition in 96 (73%) of 131 cases and a nonneoplastic condition in 23 (50%) of 46 cases. In 119 (67%) of 177 cases, a diagnosis was reached at FS-0. A correct diagnosis was made on subsequent frozen section in 28 (16%) of cases, including 21 (16%) of 131 neoplasms and 7 (15%) of nonneoplastic conditions. In 15 (54%) of 28 cases, the correct diagnosis was made on the second frozen section; in 25 (89%) of 28, the correct diagnosis was made by the fourth frozen section. In 14 (11%) of 131 neoplastic cases, a sampling error relative to the lesion resulted in an inaccurate diagnosis at FS-0. A significant error in diagnosis occurred in three cases (1.7%). CONCLUSIONS: We conclude that (1) because 58 (33%) of 177 diagnosed cases in our series would have been potentially misdiagnosed if only one biopsy had been taken at the stereotactic target, frozen section evaluation or cytologic examination of material at the time of surgery should be performed routinely to ensure that adequate tissue has been obtained for purposes of diagnosis; (2) taking up to four biopsies increases the diagnostic yield (from 67% to 89% in this series); and (3) neoplastic lesions are more likely to be definitively diagnosed at FS-0 than non-neoplastic lesions.


Subject(s)
Brain Neoplasms/diagnosis , Brain/pathology , Cerebrovascular Disorders/diagnosis , Frozen Sections , Stereotaxic Techniques , Adolescent , Adult , Aged , Aged, 80 and over , Brain Neoplasms/pathology , Cerebrovascular Disorders/pathology , Child , Female , Humans , Male , Middle Aged
18.
Am J Surg Pathol ; 21(4): 407-16, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9130987

ABSTRACT

Recently, cell size, cell density, and growth pattern were found to be reliable histologic parameters in separating benign from malignant duodenal stromal tumors. However, there are few data on the histologic features and important prognostic parameters of stromal tumors from other parts of the small bowel. Thus, we studied the clinical and pathologic features of 39 stromal tumors of the jejunum and ileum to determine which parameters would be most useful in distinguishing a benign from a malignant tumor. In all cases, the following histologic parameters were recorded: (a) predominant growth pattern (organoid, fascicular, solid, or mixed), (b) cellularity (low or high), (c) predominant cell type (spindled, epithelioid, or mixed), (d) nuclear pleomorphism (minimal, moderate, or severe), (e) the presence or absence of tumor cell necrosis, (f) the presence or absence of mucosal infiltration, (g) the presence or absence of skeinoid fibers, and (h) the number of mitotic figures per 50 high-power microscopic fields (HPF). Clinical follow-up was obtained in all cases, and the patients were considered to have suffered an adverse outcome if they developed metastatic disease or died as a complication of their tumor. In the absence of these features, patients were not considered to have suffered an adverse outcome. Twenty-five patients suffered an adverse outcome. Twenty-one patients died of disease from 1 month to 9 years (median: 2 years). One patient died at 4 days because of postoperative complications. Three patients were alive with metastatic disease at 6 months, 6 years, and 7 years. Twenty-four of these 25 patients developed metastatic disease, most commonly to the liver. Fourteen patients did not suffer an adverse outcome. Eleven patients were alive without disease from 2 to 11 years (median: 3 years), and three patients died of unrelated causes at 1, 1, and 3 years. Although there was some overlap in features between clinically benign and malignant tumors, features that were significantly associated with an adverse outcome included tumor size > 5 cm, mitotic counts > 5 mitotic figures per 50 HPF, high cellularity, the absence of a predominant organoid growth pattern, the absence of skeinoid fibers, the presence of severe nuclear pleomorphism, and the presence of mucosal infiltration and tumor cell necrosis (p < 0.05 using the chi-square and Fisher's exact tests). Features that were significantly associated with decreased survival included tumor size > 5 cm, mitotic counts > 5 mitotic figures per 50 HPF, high cellularity, the absence of skeinoid fibers, and the presence of tumor cell necrosis (p < 0.05 using the Mantel-Haenszel log-rank test). Given the fact that there is some overlap in these features between clinically benign and malignant tumors, a multiparametric analysis using the above features is the most effective way of predicting clinical behavior.


Subject(s)
Ileal Neoplasms/pathology , Jejunal Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Diagnosis, Differential , Female , Humans , Ileal Neoplasms/diagnosis , Ileal Neoplasms/mortality , Jejunal Neoplasms/diagnosis , Jejunal Neoplasms/mortality , Male , Middle Aged , Stromal Cells/pathology
19.
J Epidemiol Community Health ; 49 Suppl 2: S57-64, 1995 Dec.
Article in English | MEDLINE | ID: mdl-8594136

ABSTRACT

STUDY OBJECTIVE: To examine geographical variation in limiting long-term illness in England and Wales and assesses the extent of its similarity with the distribution of mortality rates and of deprivation. DESIGN: A geographically based study using data from the 1991 census on limiting long term illness. Maps and regression analysis are used to compare the distribution of standardised illness ratios with standardised mortality ratios and indicators of social deprivation. SETTING: A total of 401 local authority districts in England and Wales. PARTICIPANTS: The population of England and Wales enumerated in the 1991 census. MAIN RESULTS: The geographical pattern of limiting long term illness shows many similarities with that of mortality but there are also some differences. Both are positively associated with indicators of social deprivation, with limiting long term illness tending to show stronger correlations, particularly in the elderly. Most of Wales and many industrial areas of northern England have higher rates of long term illness than would be expected from their mortality rates, while much of south eastern England has lower than expected rates. CONCLUSIONS: Moves towards using data on limiting long term illness instead of standardised mortality rates would have important implications for NHS resource allocations. Further assessment of the reliability of these data on self reported morbidity is required. in particular, there is a need to assess how much they reflect real differences in ill health rather than the influence of socioeconomic or cultural factors affecting the likelihood of a positive answer to the census question on limiting long term illness.


Subject(s)
Chronic Disease , Mortality , Poverty/statistics & numerical data , Adolescent , Adult , Aged , Child , Child, Preschool , Data Interpretation, Statistical , Demography , England/epidemiology , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Poverty/classification , Poverty Areas , Unemployment , Wales/epidemiology
20.
Environ Plan A ; 27(11): 1,849-58, 1995 Nov.
Article in English | MEDLINE | ID: mdl-12347002

ABSTRACT

"Postcode addresses from National Health Service patient registers for Norfolk and Suffolk [counties in England] current on census day 1991 were assigned to census wards, and estimates of populations in wards were produced for the total population and for twelve age-sex groups. These were compared with adjusted counts of usual residents from the 1991 Census." The results indicate that family health service authority registers "are an acceptable alternative to the census for population estimation purposes. This supports recent arguments for wider use of population registers and suggests that they may be particularly valuable as a source of intercensal information."


Subject(s)
Age Distribution , Population Growth , Registries , Age Factors , Demography , Developed Countries , England , Europe , Population , Population Characteristics , Research , Statistics as Topic , United Kingdom
SELECTION OF CITATIONS
SEARCH DETAIL
...