Biomedical subjects

G Johnson

Publications and source records attributed to G Johnson.

At least 145 records · Page 8Linked to original sources

PubMed1998

Alterations of neutrophil oxidative burst by in vitro smoke exposure: implications for oral and systemic diseases.

Alterations of neutrophil functions by tobacco products may play a central role in the pathogenesis of periodontal diseases and several smoking-related systemic diseases. In the present study, we examined the in vitro effects of cigarette smoke on neutrophils at times and concentrations that may be encountered during smoke exposure. We measured the level of smoke exposure in the in vitro system by measuring the levels of nicotine and comparing these to levels in the oral cavity in smokers before and after smoking. We examined both the unstimulated and stimulated release of 2 oxidative burst products: superoxide (O-2) and hydrogen peroxide (H2O2). Salivary washings were collected from 7 smokers (> 1 pack/day) before smoking a cigarette. Immediately after they smoked a cigarette, a second set of washings was collected. In vitro exposure to smoke involved incubating aliquots of neutrophils in phosphate-buffered saline for 1 to 5 minutes. Nicotine and cotinine levels were quantitated using gas chromatography, with detection by electron impact mass spectrometry. Peripheral neutrophils were isolated from medically healthy non-smoking volunteers via a double-density gradient technique and incubated in vitro with whole cigarette smoke for 0 to 5 minutes. Phorbol myristate acetate (PMA; 10(-7) M) was used to stimulate half of the cell aliquots. Superoxide generation was assessed through the superoxide dismutase (SOD) inhibitable reduction of ferricytochrome c. H2O2 production was assessed through the H2O2-dependent breakdown of dichlorofluorescin diacetate to its fluorophore and measured by flow cytometry. There was a marked elevation in salivary nicotine concentration from before smoking (mean: 80.8 ng) to after smoking (mean 1,685 ng/mL). In the in vitro smoke box system, there was a time-related elevation in nicotine from 1 to 5 minutes (50-->136 ng/mL). In PMA-stimulated cells exposed to smoke, there was a time-related inhibition of both superoxide and H2O2 production. However, in unstimulated cells exposed to smoke, there was a time-related increase in the release of superoxide and H2O2. A novel finding in unstimulated cells exposed to smoke was that there appeared to be 2 distinct populations of cells--one of "high" H2O2 producers and one of "low" H2O2 producers. The proportion of high H2O2 producers increased relative to smoke exposure. The relative production of H2O2 in the unstimulated high producers was comparable to PMA-stimulated cells at 5 minutes. This release of superoxide and H2O2 in unstimulated cells exposed to smoke may alter the pathogenic processes both in periodontal diseases and other systemic diseases.

Analysis of Variance↗

PubMed1998

Sulfonylureas enhance exocytosis from pancreatic beta-cells by a mechanism that does not involve direct activation of protein kinase C.

Hypoglycemic sulfonylureas stimulate insulin release by binding to a regulatory subunit of plasma membrane ATP-sensitive K+ (K(ATP)) channels. The consequent closure of K(ATP) channels leads to depolarization, opening of voltage-dependent Ca2+ channels, Ca2+ influx, and a rise in intracellular [Ca2+]. Recently, however, it has been suggested that sulfonylureas may have an additional action on secretion, independent of changes in intracellular [Ca2+] but dependent on the activity of protein kinase C (PKC). We have investigated the mechanisms involved in the PKC-dependent effect of sulfonylureas on the secretion machinery in beta-cells. In MIN6 beta-cells permeabilized by streptolysin O, insulin release was stimulated by elevation of [Ca2+] from 10(-8) to 10(-5) mol/l. At a [Ca2+] of 10(-8) mol/l, insulin release from permeabilized beta-cells was stimulated by addition of GTP-gamma-S, or by addition of a phorbol ester, 12-O-tetradecanoylphorbol 13-acetate (TPA). TPA, but not GTP-gamma-S, also increased insulin release when [Ca2+] was 10(-5) mol/l. Insulin release from permeabilized beta-cells was stimulated by tolbutamide (0.1-1 mmol/l) at 10(-8) but not at 10(-5) mol/l Ca2+. The effect of tolbutamide was blocked either by inhibition of PKC or when phorbol ester-sensitive PKC isoforms were maximally stimulated by TPA. Meglitinide and glibenclamide also stimulated insulin release from permeabilized beta-cells. To assess the possibility that direct activation of PKC mediates the exocytotic response to sulfonylureas, we studied the effect of tolbutamide and glibenclamide on PKC activity. Purified brain PKC was not activated by tolbutamide or glibenclamide, whether tested in the absence or presence of phosphatidylserine or TPA, or at low or high [Ca2+]; nor was the total PKC activity in extracts of MIN6 beta-cells affected by tolbutamide. Neither tolbutamide nor glibenclamide elicited translocation of any isoform of PKC in intact or permeabilized beta-cells under conditions in which TPA evoked a marked redistribution of PKC alpha- and epsilon-isoforms. We conclude that although the plasma membrane K(ATP) channel-independent stimulation of exocytosis by sulfonylureas may require functional PKC, the mechanism does not involve a direct activation of the enzyme.

Animals↗

PubMed1998

A prototype molecular interactive collaborative environment (MICE).

Illustrations of macromolecular structure in the scientific literature contain a high level of semantic content through which the authors convey, among other features, the biological function of that macromolecule. We refer to these illustrations as molecular scenes. Such scenes, if available electronically, are not readily accessible for further interactive interrogation. The basic PDB format does not retain features of the scene; formats like PostScript retain the scene but are not interactive; and the many formats used by individual graphics programs, while capable of reproducing the scene, are neither interchangeable nor can they be stored in a database and queried for features of the scene. MICE defines a Molecular Scene Description Language (MSDL) which allows scenes to be stored in a relational database (a molecular scene gallery) and queried. Scenes retrieved from the gallery are rendered in Virtual Reality Modeling Language (VRML) and currently displayed in WebView, a VRML browser modified to support the Virtual Reality Behavior System (VRBS) protocol. VRBS provides communication between multiple client browsers, each capable of manipulating the scene. This level of collaboration works well over standard Internet connections and holds promise for collaborative research at a distance and distance learning. Further, via VRBS, the VRML world can be used as a visual cue to trigger an application such as a remote MEME search. MICE is very much work in progress. Current work seeks to replace WebView with Netscape, Cosmoplayer, a standard VRML plug-in, and a Java-based console. The console consists of a generic kernel suitable for multiple collaborative applications and additional application-specific controls. Further details of the MICE project are available at http:/(/)mice.sdsc.edu.

Computational Biology↗

PubMed1998

A clinical decision analysis of cryotherapy compared with expectant management for cervical dysplasia.

BACKGROUND: Screening for precursors of cervical cancer with colposcopic examination for women with abnormal Papanicolaou (Pap) smears identifies those with cervical dysplasia. Though the majority of mild dysplasias (CIN I) will regress, many are treated with cryotherapy. METHODS: We used decision analysis to compare immediate cryotherapy with expectant management (following with another Pap smear or colposcopy, with treatment reserved for progression or a duration of 2 years). The decision tree included the possibility of more invasive surgical procedures if the cryotherapy was ineffective or if the dysplasia progressed in extent of cervical involvement or in grade. Probabilities were derived from literature review and expert judgment. The analysis considered the disutility of the follow-up examinations, cryotherapy, and the more invasive procedures, using expert assessment. RESULTS: Using the baseline assumptions, expectant management led to a better outcome for most patients (57%), who recover with no procedure. However, more patients treated with expectant management required surgical procedures (loop electrosurgical excisional procedure, conization, or, rarely, hysterectomy) than did those treated with immediate cryotherapy. In the expected disutility analysis, expectant management was better than immediate cryotherapy. Sensitivity analysis showed that three factors had the potential to change the recommendation of the analysis: (1) the probability the dysplasia will regress, (2) the disutility of the process of expectant management, and (3) the disutility of invasive procedures compared with cryotherapy. CONCLUSIONS: The analysis indicated that expectant management is preferable to immediate cryotherapy for women with histologically proven mild cervical dysplasia. However, this conclusion depended on assumptions about three factors for which there is insufficient evidence in the literature. More research is needed.

Colposcopy↗

PubMed1998

Radiologic surveillance of acoustic neuromas.

OBJECTIVE: This study aimed to define the incidence and rate of tumor growth of acoustic neuromas (ANs) in patients who have undergone radiologic surveillance. DATA SOURCES: MEDLINE literature searches covering the period of January 1966-June 1997 were performed as well as a review of the bibliographies of the studies that were found. STUDY SELECTION: Criteria for inclusion of a study in this metaanalysis were: a defined group of patients diagnosed with an AN for whom radiologic surveillance was the selected strategy of management, limited inclusion of patients with neurofibromatosis type II (NF II) ANs, no recurrent ANs, data that could be extracted and pooled with other studies, and no duplication of patient populations between studies. Thirteen studies were selected. DATA EXTRACTION: Quality of the studies was determined by the design of each study and the ability to combine the data with the results of other studies. All of the studies were biased by their retrospective, nonrandomized nature. DATA SYNTHESIS: Paired t-tests (p < 0.05) and correlation coefficients were used to assess pooled data. CONCLUSIONS: A total of 571 ANs were studied, with an average patient age of 64 years. Given an average follow-up period of 3 years, 54% of patients showed evidence of radiologic growth. No reliable predictors of tumor growth have been identified. The authors suggest that radiologic surveillance may best be applied to those patients who refuse treatment, who have a tumor in the only-hearing ear, or who are medically unable to undergo treatment. Small tumor size and advanced age should not be viewed as absolute contraindications for treatment.

Aftercare↗

PubMed1997

The regulation of anoikis: MEKK-1 activation requires cleavage by caspases.

Certain cell types undergo apoptosis when they lose integrin-mediated contacts with the extracellular matrix ("anoikis"). The Jun N-terminal kinase (JNK) pathway is activated in and promotes anoikis. This activation requires caspase activity. We presently report that a DEVD motif-specific caspase that cleaves MEKK-1 specifically is activated when cells lose matrix contact. This cleavage is required for the activation of the kinase activity. When overexpressed, the MEKK-1 cleavage product stimulates apoptosis; the wild-type, full-length MEKK-1 sensitizes cells to anoikis; and a cleavage-resistant mutant of MEKK-1 partially protects cells against anoikis. The cleavage-resistant or kinase-inactive mutants also prevent caspase-7 from being activated completely. Thus, caspases can induce apoptosis by activating MEKK-1, which in turn activates more caspase activity, comprising a positive feedback loop.

Amino Acid Sequence↗

PubMed1997

99mTc-HL91. Effects of low flow and hypoxia on a new ischemia-avid myocardial imaging agent.

BACKGROUND: 99mTc-HL91 is a potential imaging agent that has demonstrated increased uptake in hypoxic tumor cells. The purpose of this study was to determine if 99mTc-HL91 demonstrates increased uptake and retention in ischemic and hypoxic myocardium. METHODS AND RESULTS: 99mTc-HL91 (11.1 MBq) was infused over 10 minutes, followed by a 60-minute clearance phase. Activity was monitored by using an NaI detector. Three groups were studied using Krebs-Henseleit buffer (KH): controls (12 mL/min, n = 6), low-flow ischemic (1 mL/min, n = 7), and hypoxic (12 mL/min, n = 8). Two groups were perfused with KH, red blood cells, and albumin: controls (6 mL/min, n = 6) and low-flow ischemic (0.5 mL/min, n = 6). For the KH hearts, the 99mTc-HL91 peak uptake progressively increased from control (6.3 +/- 0.5 microCi, mean +/- SEM) to hypoxic (9.1 +/- 1.0 microCi) to low flow (44.0 +/- 2.6 microCi; P < .01). The peak uptake low-flow/control ratio was 7:1. Final retention increased progressively from control (0.8 +/- 0.1 microCi) to hypoxic (2.9 +/- 0.5 muCi) to low flow (10.9 +/- 1.3 microCi; P < .01). The final low-flow/control activity ratio was 13.6:1. Similar results were observed in the red blood cell-perfused control and low-flow groups. CONCLUSIONS: This study introduces a new myocardial "hot spot" imaging agent, 99mTc-HL91. This agent demonstrates increased myocardial uptake and retention in hypoxic and low-flow ischemic models. Further in vivo imaging studies are warranted to determine the clinical potential of this agent.

Animals↗

PubMed1997

Risk factors for post-stroke depression.

OBJECTIVE: To examine possible risk factors in post-stroke depression (PSD) other than site of lesion in the brain DATA SOURCES: 191 first-ever stroke patients were examined physically shortly after their stroke and examined psychiatrically and physically 4 months post-stroke. SETTING: A geographically defined segment of the metropolitan area of Perth, Western Australia, from which all strokes over a course of 18 months were examined (the Perth Community Stroke Study). MEASURES: Psychiatric Assessment Schedule, Mini Mental State Examination, Barthel Index, Frenchay Activities Index, physical illness and sociodemographic data were collected. Post-stroke depression (PSD) included both major depression and minor depression (dysthymia without the 2-year time stipulation) according to DSM-III (American Psychiatric Association) criteria. Patients depressed at the time of the stroke were excluded. PATIENTS: 191 first-ever stroke patients, 111 M, 80 F, 28% had PSD, 17% major and 11% minor depression. RESULTS: Significant associations with PSD at 4 months were major functional impairment, living in a nursing home, being divorced and having a high pre-stroke alcohol intake (M only). There was no significant association with age, sex, social class, cognitive impairment or pre-stroke physical illness. CONCLUSION: Results favoured the hypothesis that depression in an unselected group of stroke patients is no more common, and of no more specific aetiology, than it is among elderly patients with other physical illness.

Activities of Daily Living↗

PubMed1997

Regulation of promoter-CAT stress genes in HepG2 cells by suspensions of particles from ambient air.

A panel of HepG2-derived cell lines (CAT-Tox [L] assay, Xenometrix), harboring stress genes consisting of a sequence for chloramphenicol acetyltransferase (CAT) under the transcriptional regulation from mammalian promoters and response elements, was exposed for 18-24 hr to aqueous suspensions of urban dusts (SRM-1648, SRM-1649, EHC-93) or PM2.5 particles (particulate matter < 2.5 micron). Expression of CAT protein was measured by enzyme-linked immunosorbent assay. Induction of the CAT genes was verified with benzo[a]pyrene (CYP1A1, cytochrome P450 1A1 promoter; GSTYa, glutathione transferase subunit Ya promoter; XRE, xenobiotic response element), cadmium sulfate, and copper sulfate (HMTIIa, metallothionein IIa promoter; HSP70, heat shock protein 70 promoter). The urban dust suspensions were active on CYP1A1, GSTYa, and XRE cell lines. SRM-1648 and SRM-1649 were twice as potent as EHC-93 per unit mass in inducing the xenobiotic-dependent responses, which correlated with contents in polycyclic aromatic hydrocarbons. These three reference particles, as well as six PM2.5 preparations collected on hi-vol filters in the Great Lakes basin, were also found to induce HMTIIa and HSP70, the magnitude of the responses correlating closely with the amount of soluble copper in the particulate preparations. The results indicate that bioavailable chemical species in the unfractionated particles can directly and quantitatively induce xenobiotic, metal, and stress-dependent responses in a target cell model, resulting in patterns of gene induction consistent with the chemical compositions of the environmental materials. We propose that cell culture models could be helpful for toxicodynamic inferences in adjunct to environmental monitoring and exposure assessments.

Air Pollutants↗

PubMed1997

Profile of numbers of sequence differences among V-genes coding for the variable regions of T cell receptor for antigen alpha and beta chains.

When human T cell receptor for antigen (TCR) alpha chain V-genes were compared pair-wise, the numbers of nucleotide differences showed a characteristic distribution; most were in the range of 100 to 200 differences out of a total of about 300 bases. The same distribution was observed for mouse TCR alpha chains. Even more interesting was that comparing human alpha chains and mouse alpha chains gave essentially the same nucleotide difference pattern. It is inferred from the large number of differences and from the nonspecificity of trans-species (human and mouse) nucleotide sequence differences of TCR V-genes that TCR alpha chains probably diverged early during evolution. The same feature was also observed for human and mouse TCR beta chains, although the alpha and beta chain V-genes were distinct. This evolutionary preservation could be of vital importance to the fidelity of the complicated trimolecular interactions among TCR alpha and beta chains, the processed peptide, and the major histocompatibility complex (MHC) class I or II molecules.

Animals↗

PubMed1997

Mechanism of initial attachment of corneal epithelial cells to polymeric surfaces.

The initial attachment of cultured bovine corneal epithelial cells and stromal fibroblasts to two oxygen-containing synthetic polymers was studied. Cultured epithelial cells and stromal fibroblasts were seeded onto two oxygen-containing surfaces: 'tissue culture' polystyrene (TCPS) and a polymer film deposited by RF plasma deposition using a methylmethacrylate monomer (MMA/FEP). To establish the mechanism of cell attachment, the effect of the selective removal of the vitronectin and fibronectin from the serum used in the culture medium was tested. The attachment of cultured epithelial cells during the first 90 min of culture was reduced by 40% (TCPS)-80% (MMA/FEP) as a result of removing vitronectin from the medium. Attachment of these cells to TCPS was reduced by 85-95% when the serum was depleted of both fibronectin and vitronectin. However, depletion of fibronectin reduced cell attachment to TCPS by 20%, whilst on MMA/FEP cell attachment was equivalent, or higher, than that for intact serum. The attachment of cultured corneal stromal fibroblasts was similarly dependent on vitronectin but less dependent on fibronectin. Therefore, for the attachment of both cultured epithelial cells and fibroblasts to oxygen-containing surfaces in the presence of serum, there is a high requirement for serum vitronectin but a lesser requirement for fibronectin. The effects of the establishment of corneal epithelial cells in culture and the site of origin of the cells, were determined. Primary isolates of epithelial cells isolated from the limbal, central or peripheral regions of the cornea were less dependent on vitronectin for initial attachment to TCPS than were these cells after several passages in culture. Furthermore, the primary isolates were dramatically less responsive to vitronectin than the cultured cells. These results indicate that the mechanism of attachment of corneal epithelial cells to TCPS varies with the culture experience of the cells. Cells that are culture neophytes can employe endogenous mechanisms for the initial attachment to TCPS, whereas cells established in culture are dependent on exogenous vitronectin in order to attach.

Animals↗

PubMed1997

Variable domain structure of kappaIV human light chain Len: high homology to the murine light chain McPC603.

Antibody light chains of the kappa subgroup are the predominant light chain component in human immune responses and are used almost exclusively in the antibody repertoire of mice. Human kappa light chains comprise four subgroups. To date, all crystallographic studies of human kappa light chains were carried out on proteins of the kappaI subgroup. The light chain produced by multiple myeloma patient Len. was of the kappaIV subgroup, it differed by only one residue from the germ-line gene encoded protein. The variable domain fragment of the light chain was crystallized from ammonium sulfate in space group C222(1). The crystal structure was determined by molecular replacement and refined at 1.95 A resolution to an R-factor of 0.15. Protein Len has six additional residues in its CDR1 segment compared to the kappaI proteins previously characterized. The kappaIV variable domain, Len, differs in only 23 of 113 residues from murine kappa light chain McPC603. The RMS deviation upon superimposing their alpha-carbons was 0.69 A. The CDR1 segment of the human and murine variable domains have the same length and conformation although their amino acid sequences differ in 5 out of 17 residues. Structural features were identified that could account for the significantly higher stability of the human kappaIV protein relative to its murine counterpart. This human kappaIV light chain structure is the closest human homolog to a murine light chain and can be expected to facilitate detailed structural comparisons necessary for effective humanization of murine antibodies.

Amino Acid Sequence↗

PubMed1997

An acute phase reaction in diabetic patients with foot ulcers.

The acute phase reaction is a molecular response to noxious stimuli. Over 50 glycoproteins have been identified as reactants. While this is likely a protective response, some of the changes could be detrimental to body homeostasis. The objective of this study was to examine whether an acute phase reaction occurs in diabetic patients with foot ulcers. In age- and sex-matched populations, measurements of C-reactive protein, fibrinogen, albumin, hematocrit, whole blood viscosity and protein C were performed on: (i) 24 diabetic patients with a foot ulcer (group A); (ii) eight diabetic patients without foot ulcer (group B); and (iii) seven patients without diabetes (group C). Analysis of variance was used to compare means of each respective group (mean (s.d.)). Group A demonstrated an increase in C-reactive protein (5.6 (5.4) mg/dl) compared with group B (0.78 (0.46) mg/dl; P = 0.013) and group C (0.71 (0.26) mg/dl; P = 0.026). Fibrinogen was also increased in group A (619 (205) mg/dl) compared with group B (310 (58) mg/dl; P = 0.005) and group C (370 (88) mg/dl; P = 0.04). Hematocrit (37 (6)%) and albumin (3.5 (0.5) g/dl) were decreased in group A compared with group B (hematocrit 46 (4)%; P < 0.0001; albumin 4.3 (0.3) g/dl; P = 0.0005) and group C (hematocrit 45 (3)%; P = 0.005; albumin 4.6 (0.3) g/dl; P < 0.0001). No difference was found in whole blood viscosity and levels of protein C. There also was no significant difference demonstrated between any of the parameters studied when comparing groups B and C. In conclusion, these results indicate that diabetic patients with a foot ulcer undergo an acute phase reaction as evidenced by a rise in C-reactive protein and fibrinogen compared with diabetic patients without a foot ulcer and normal control patients. As more is learned about the acute phase reaction, this information may prove valuable in the management of the diabetic patient.

Acute-Phase Reaction↗

PubMed1997

A method of estimating the numbers of human and mouse T cell receptors for antigen alpha and beta chain V-genes.

T cell receptors for antigen (TCR) V-genes are under a very restrictive evolutionary pressure in order to maintain their biological activities of interacting with MHC class I or II molecules and processed peptides at the protein level. This is in contrast to immunoglobulin V-genes which can mutate more freely. As we have discussed before, 17 or less nucleotide differences between any two mouse lambda light chain V-genes can be due to somatic mutations induced by antigens, allelic variations, and the combination of these two mechanisms. Thus, a cut-off of 17 nucleotide differences has been used to estimate the numbers of the other human and mouse immunoglobulin chain V-genes. Except for mouse heavy chains where experimental study is not yet available, our estimated numbers are in good agreement with experimental findings. For TCR V-genes, however, this cut-off value should be modified as illustrated in the present analysis. Our estimation of the number of human TCR beta chain V-genes is also in good agreement with the recent experimental study of sequencing 685 kb of that gene locus. Estimations for the numbers of human alpha, mouse alpha and beta chain V-genes will wait for future experimental verification.

Animals↗

PubMed1997

The effects of bolus size and chewing rate on masticatory performance with artificial test foods.

To better understand 'within subject' variability in masticatory performance of artificial food, this study evaluates the effects of bolus size and chewing rate. Twenty young adult male subjects each participated in two experiments evaluating their ability to process an artificial food (CutterSil). Based on the frequency distributions for the weights of the chewed particles, median particle size and broadness of the particle distribution were estimated. Controlling for the number of chews, the effect of (1) bolus size was evaluated by having each subject chew one whole tablet, four quarters, three quarters or two quarters; (2). chewing rate was evaluated by having the subjects chew first habitually, then at slow (40 cycles/min) and fast (100 cycles/min) rates. The results showed that median particle sizes decreased and the distribution of particles widened with decreasing bolus size. The slow chewing rate produced the smallest particles with the widest distributions, followed by the habitual and fast rates, respectively. The study has shown that bolus size and chewing rate are important source of variation which must be considered in studies of masticatory performance.

Adult↗

PubMed1997

Genetic structure of populations of the threatened eastern massasauga rattlesnake, Sistrurus c. catenatus: evidence from microsatellite DNA markers.

Throughout its distribution in North America, the threatened eastern massasauga rattlesnake (Sistrurus c. catenatus) persists in a series of habitat-isolated disjunct populations of varying size. Here, we use six microsatellite DNA loci to generate information on the degree of genetic differentiation between, and the levels of inbreeding within populations to understand how evolutionary processes operate in these populations and aid the development of conservation plans for this species. Samples were collected from 199 individuals from five populations in Ontario, New York and Ohio. Our results show that all sampled populations: (i) differ significantly in allele frequencies even though some populations are < 50 km apart, and may contain genetically distinct subpopulations < 2 km apart; (ii) have an average of 23% of alleles that are population specific; and (iii) have significant FIS values (mean overall FIS = 0.194) probably due to a combination of Wahlund effects resulting from fine-scale genetic differentiation within populations and the presence of null alleles. Our results imply that massasauga populations may be genetically structured on an extremely fine scale even within continuous populations, possibly due to limited dispersal. Additional information is needed to determine if dispersal and mating behaviour within populations can account for this structure and whether the observed differentiation is due to random processes such as drift or to local adaptation. From a conservation perspective, our results imply that these massasauga populations should be managed as demographically independent units and that each has high conservation value in terms of containing unique genetic variation.

Animals↗

PubMed1997

Which patients will benefit from psychosocial intervention after cystectomy for bladder cancer?

OBJECTIVES: To investigate: (i) if early psychosocial intervention after cystectomy for bladder cancer can assist psychosocial rehabilitation; (ii) if the outcome of such intervention correlates with the patient's psychological defensive strategies as revealed with the meta-contrast technique (MCT); and (iii) if the patient's general philosophical outlook is important in this context. PATIENTS AND METHODS: Of 50 patients who had undergone radical cystectomy for bladder cancer, 17 received an ileal conduit, 17 a continent urinary reservoir with abdominal stoma and 16 an orthotopic neobladder. Twenty-four of the patients were randomized to psychosocial intervention, comprising weekly counselling 4-9 weeks after surgery. All patients were then evaluated with the Sickness-Impact Profile (SIP) standard questionnaire and the MCT (a projective test of percept-genetic model) was used to reflect individual defensive strategies at the subconscious or unconscious level. The patient's general philosophical outlook was recorded before and after surgery. RESULTS: There was no significant difference in the results of the SIP between the intervention and the non-intervention group, as a whole or in its psychosocial dimension. However, intervention benefited patients with continent cutaneous diversion, whose scores on the psychosocial SIP dimension were lower than in the groups with ileal conduit diversion or orthotopic bladder replacement (P < 0.05). The MCT analysis of defensive strategies identified three clusters of patients characterized mainly by isolation and repression, repression and stereotypy or sensitivity and stereotypy. Analysis for cluster identification showed no significant SIP score differences between intervention and non-intervention groups. In an analysis of single defensive strategies, stereotypy was associated with higher total SIP score, but not significantly. Three clusters of philosophical outlook were identified; in one cluster, characterized by a belief in a supernatural power and philosophical interest, the psychosocial SIP scores were lower in the patients who obtained emotional support and the reverse in a cluster with contrary attitudes, although neither differences were significant. CONCLUSION: Psychosocial intervention assisted the psychosocial rehabilitation of patients with continent cutaneous urinary diversion. Defensive strategies and philosophical outlook generally did not influence the outcome of intervention. However, such programmes may be helpful for some patients, mainly those with a basically pessimistic disposition, a general interest in philosophical questions and often using defensive strategies of stereotypy and repression.

Aged↗

PubMed1997

Outcomes study of a course in breast-cancer screening.

BACKGROUND: The Breast Cancer Screening Module is a professional training course within the Professional Education for Prevention and Early Detection (PEPED) program at the University of Texas M. D. Anderson Cancer Center. An outcomes study was done to determine the module's ability to improve screening practices crucial to breast-cancer control. METHODS: The five-day course combines 17 hours of class work with 20 hours of hands-on clinical training. Subjects were followed for one year post-training. Six outcome areas were evaluated: 1) knowledge about breast-cancer prevention; 2) clinical skills; 3) changes in routine practice; 4) numbers of patients screened, referred, and diagnosed; 5) trainee satisfaction with the course; and 6) barriers to implementing screening in routine practice. The study population was 63 subjects (all nurse professionals). RESULTS: Outcomes were positive in all six evaluation areas-significant gains in general and clinical knowledge tests (p < or = 0.05); a significant increase from 54.2% pre-training to 70.5% post-training in risk counseling (p < or = 0.05); a sustained increase in screening practices (4.3 times and 2.8 times greater at 6 and 12 months post-training, respectively); 72% rate of high course satisfaction; and barriers to improved screening practices, such as time limitations among 60.4% of subjects and 57.6% of their employers, were identified. CONCLUSIONS: This unique training enhances breast-cancer prevention and screening practices and early detection.

Breast Neoplasms↗