Psychophysiology of pain: diagnostic and therapeutic implications

Pain problems occupy muct of the time and therapeutic efforts of physicians. Nonmedical practitioners and cultists have likewise attracted many people seeking pain relief. In many cases the cultists seem to do as well as the ethical practitioner. A realistic view of pain takes into account the significance of the pain to the individual, the degree of anxiety and/or depression that contributes to the aggravation and prepetuation of the pain, and finally the manipulative and defensive value that the pain may have to the individual. A purely mechanistic approach which would attempt to distinguish "real pain", ie, pain associated with a demonstrable lesion, and "imagined pain" will prove counterproductive. Likewise accusations of consciously pretended pain or malingering tend to be nontherapeutic. A sound therapeutic approach is to regard all pain as real, realizing that the pain of depression may be the most unendurable type of pain. Major psychotropic drugs for relief of anxiety and for treatment of depression have appplication in the management of selected pain problems.     

Marker antibodies of rheumatoid arthritis: diagnostic and pathogenetic implications

Rheumatoid arthritis (RA) is associated with several autoantibodies specific enough to serve as diagnostic and prognostic markers. These include rheumatoid factor (RF), antikeratin antibody (AKA), antiperinuclear factor (APF), and anti-RA33. The first three, and possibly also anti-RA33, may precede the onset of clinical RA. The prevalence of positive test reactions depends on the period between taking the specimen and onset of disease; when the period is short, the prevalence is nearly the same as in established disease. Thus, RA has a long asymptomatic period with broadening immunological activity. The assays for AKA and APF (and possibly also for anti-RA33), compared with RF testing, yielded greater specificity rather than the ability to define any subgroup with particularly severe disease. Used together, the above marker antibodies may form a new and more enlightened basis for defining seropositive RA. It is commonly believed that genetically mediated immune response plays an important role in the initiation of RA. However, the role of the major histocompatibility complex antigens may be in modulation of the inflammatory reaction in a later phase.     

A model of the prostate gland for use in internal dosimetry

Several radionuclides or radiolabeled pharmaceuticals may be taken up by the prostate gland. METHODS: A model of the prostate gland has been developed and implemented in the adult male mathematical phantom within software which calculates absorbed fractions of energy from activity in source regions within the phantom. RESULTS: Specific absorbed fractions are reported for all target regions within the phantom for 12 discrete source energies from 0.01 to 4.0 MeV. S-values for all target regions for six radionuclides are also reported. CONCLUSIONS: This work provides another organ useful for internal dose calculations within the 70-kg phantom.     

Helicobacter pylori and gastric acid: biological and therapeutic implications

Helicobacter pylori is highly adapted to its unusual ecological niche in the human stomach. Urease activity permits H. pylori survival at a pH of <4 in vitro and is required for the organism to colonize in animal models. However, urease does not play an important role in the survival of the organism in a pH range between 4 and 7. Other mechanisms of pH homeostasis remain poorly understood, but preliminary studies indicate that novel proteins are produced when H.pylori cells are shifted from pH 7 to 3, and the gene encoding a P-type adenosine triphosphatase that may catalyze NH4+/H+ exchange across the cytoplasmic membrane has been cloned. Mechanisms of pH homeostasis in other enteric bacteria are reviewed and provide insight into additional pathways that may be used by H. pylori. An important adaptation of H. pylori to the gastric environment may be its ability to alter gastric acid secretion. Acute infection is associated with transient hypochlorhydria, whereas chronic infection is associated with hypergastrinemia and decreased somatostatin levels. Thus, the survival of H. pylori in the gastric environment may be attributed to both the development of specialized intrinsic defenses and the organism's ability to induce physiological alterations in the host environment.     

Cytogenetic analysis of aggressive meningiomas: possible diagnostic and prognostic implications

BACKGROUND: Published karyotypes from aggressive (atypical and malignant) meningiomas are few, but suggest clonal evolution from benign tumors with monosomy 22 to aggressive forms with additional abnormalities. The goal of this study was to identify the most frequent karyotypic abnormalities associated with aggressive histopathology and biologic behavior. METHODS: Eight intracranial meningiomas exhibiting histologically atypical features at the time of intraoperative diagnosis were chosen for cytogenetic analysis. The study set was comprised entirely of histologically atypical meningiomas. Four were considered malignant; three on the basis of brain invasion and one due to extracranial metastases. None was histologically anaplastic. RESULTS: Chromosomal abnormalities were demonstrated in 6 cases (75%), 5 of which were complex (63%). Loss of chromosome 22 was identified in two cases, both of which were associated with additional aberrations. Abnormalities most frequently involved chromosomes 1 (63%), 3 (50%), and 6 (63%). Four cases (50%) had dicentric or ring chromosomes. An additional 47 previously reported karyotypes from atypical and malignant meningiomas were reviewed. Comparison with published karyotypes of 200 histologically benign meningiomas served to underscore the increased frequency of complex karyotypes, chromosome 1, 3, and 6 abnormalities, and telomeric associations in the aggressive tumors. Apparently normal karyotypes as well as monosomy 22 alone were more frequently associated with benign, nonatypical histopathology. CONCLUSIONS: These findings suggest a possible role for cytogenetic analysis in determining the prognosis and perhaps in refining the diagnosis of atypical or aggressive meningiomas. Further studies are necessary to determine the significance of complex karyotypes, chromosome 1, 3, and 6 abnormalities, and telomeric associations, particularly whether they portend a more aggressive clinical course in meningiomas lacking features of histologic atypia.     

Genomic individuality and its biological implications

It is a widely accepted fundamental concept that all somatic genomes of a human individual are identical to each other. The theoretical basis of this concept is that all of these somatic genomes are the descendants of the genome of a single fertilized cell as well as the simple replicated products of asexual reproduction, thus not forming any new recombined genomes. The question here is whether such a concept might only represent one side of somatic genome biology and, even worse, whether it has perhaps already led to a very prevalent misconception that within the organism body, there exists no variability among individual somatic genomes. A hypothesis, called genomic individuality, is proposed, simply saying that every individual somatic genome, perhaps with rare exceptions, has its own unique or individual 'genetic identity' or 'fingerprint', which is characterized by its distinctive sequences or patterns of deoxyribonucleic acid molecules, or both. Thus, no two somatic genomes can be identical to each other in every or all aspects, and consequently, there must be a great deal of genomic variation present within the body of any multicellular organism. The concept or hypothesis of genomic individuality would not only provide a more complete understanding of genome biology, but also suggest a new insight into the studies of the biology of cells and organisms.     

Algorithms vie for diagnostic role in prostate cancer

The conventional radiographs and urgent short tau inversion recovery (STIR) magnetic resonance image (MRI) examinations of 27 consecutive patients with occult bony injuries were prospectively analysed over a 12 month period. A STIR MRI study was undertaken where the plain films were normal (n = 15) or inconclusive (n = 12) and where the patients' clinical setting was highly suggestive of an underlying bony injury. In six patients, MRI only revealed soft-tissue injuries or joint effusions and did not demonstrate any bony injury but in the remainder fractures or bone contusions were shown to be present. The MRI studies were performed on a 0.2 Tesla lower field strength unit and the examinations were expeditiously performed, inexpensive, and done on a priority basis between electively booked patients. Radio-isotope studies were not available and hence were not included in the study protocol. Apart from demonstrating the value of STIR MRI (without additional T1-weighted sequences in most patients), the purpose of this study was to highlight the alteration in management in 18/27 patients (66%) and the significant alteration in management in six of these patients.     

Narrow complex tachycardia with VA block: diagnostic and therapeutic implications

To review our experience with cases of narrow complex tachycardia with VA block, highlighting the difficulties in the differential diagnosis, and the therapeutic implications. Prior reports of patients with narrow complex tachycardia with VA block consist of isolated case reports. The differential diagnosis of this disorder includes: automatic junctional tachycardia, AV nodal reentry with final upper common pathway block, concealed nodofascicular (ventricular) pathway, and intra-Hissian reentry. Between June 1994 and January 1996, six patients with narrow complex tachycardia with episodes of ventriculoatrial block were referred for evaluation. All six patients underwent attempted radiofrequency ablation of the putative arrhythmic site. Three of six patients had evidence suggestive of a nodofascicular tract. Intermittent antegrade conduction over a left-sided nodofascicular tract was present in two patients and the diagnosis of a concealed nodofascicular was made in the third patient after ruling out other tachycardia mechanisms. Two patients had automatic junctional tachycardia, and one patient had atrioventricular nodal reentry with proximal common pathway block. Attempted ablation in the posterior and mid-septum was unsuccessful in patients with nodofascicular tachycardia. In contrast, those with atrioventricular nodal reentry and automatic junctional tachycardia readily responded to ablation. The presence of a nodofascicular tachycardia should be suspected if: (1) intermittent antegrade preexcitation is recorded, (2) the tachycardia can be initiated with a single atrial premature producing two ventricular complexes, and (3) a single ventricular extrastimulus initiates SVT without a retrograde His deflection. The presence of a nodofascicular pathway is common in patients with narrow complex tachycardia and VA block. Unlike AV nodal reentry and automatic junctional tachycardia, the response to ablation is poor.     

Cribriform carcinoma of the prostate and cribriform prostatic intraepithelial neoplasia: incidence and clinical implications

Cribriform neoplasia of the prostate can be recognized easily. However, controversy persists regarding terminology, particularly with the intraductal spread of cribriform neoplasia; some consider this "intraductal carcinoma," whereas consensus meetings defined these lesions as high-grade cribriform prostatic intraepithelial neoplasia (HGCP). This study attempts to identify the incidence and clinical significance of HGCP and cribriform carcinoma (CC) by evaluating 114 radical prostatectomy specimens. Cases were divided into three histologic groups for statistical analysis: (1) pure acinar carcinoma: infiltrating acinar carcinoma without evidence of cribriform neoplasia; (2) CC: acinar carcinoma with CC; and (3) HGCP: acinar carcinoma with HGCP. High-grade cribriform prostatic intraepithelial neoplasia was defined as the presence of neoplastic cells spanning the entire lumen in a cribriform configuration in which a basal cell layer could be shown by immunohistochemistry. Similar areas in which no basal cell layer could be seen were diagnosed as CC. The incidence of cribriform neoplasia was 38% (43 of 114). The incidences of HGCP and CC were 13% (15 of 114) and 25% (28 of 114), respectively. Univariate analysis showed a strong association between HGCP and CC both and several preoperative and final pathology results, including digital rectal examination, pathology tumor stage, extraprostatic extension, surgical margin positivity, high Gleason sum (GS), and high tumor volume. Kaplan-Meier analysis showed HGCP to have a 61% cumulative prostate-specific antigen (PSA) failure rate in contrast with CC and pure acinar cancer, which had cumulative PSA failure rates of 15% and 13%, respectively (p = 0.0001, log-rank test). Multivariate Cox's proportional-hazards analysis found preoperative serum PSA, GS, tumor stage, and volume to be important predictors of PSA failure. In a second regression model that included serum PSA, GS, and pathology tumor stage, HGCP was an independent predictor of PSA failure. Both HGCP and CC are closely associated with several poor prognostic indicators, including advanced pathology tumor stage, a high GS, and serum PSA. Multivariate analysis showed HGCP as an independent prognostic indicator. The close association between high tumor volume and HGCP supports the theory that the development of HGCP is a late event in tumor progression, more compatible with the intraductal spread of tumor than dysplasia.     

Lactic acid and protein interactions: implications for the NMR visibility of lactate in biological systems

The addition of bovine serum albumin (BSA) to a solution of lactate and alanine resulted in the disappearance of the 1H-NMR resonances from lactate but not alanine. As temperature is increased lactate becomes increasingly NMR visible and after heating above 65 degreesC and cooling to 25 degreesC lactate binding is reduced. With a concentration of 0.2 mM BSA, there was a linear relationship between NMR visible lactate versus total lactate over a range of lactate concentrations of 0.2-35 mM (slope 0.384+/-0.003) indicating that approx. 60% of the added lactate is not visible in the 1H-NMR spectrum. With a 0.1 mM BSA solution, however, the slope was markedly higher indicating that under these conditions only 25-30% of the lactate was NMR invisible. The results from this study indicate that decreased NMR visibility of lactate in proteinaceous solutions is due to non-specific binding which is dependent on the tertiary structure of the protein. This has important implications not only for the interpretation of in vivo 1H-NMR experiments but also for 13C, and 14C studies of metabolism.     

A model for the number of cores per prostate biopsy based on patient age and prostate gland volume

Investigation of the hepatitis C virus (HCV) life cycle is limited by the lack of an efficient cell culture system. Employing a tetracycline-regulated gene expression system we generated a panel of continuous human cell lines allowing the inducible expression and faithful processing of HCV structural proteins as well as of a functional NS2-3 autoprotease. HCV proteins were found in the cytoplasm in a pattern characteristic for the endoplasmic reticulum. High-level expression of HCV proteins was found to be cytotoxic. These cell lines represent a unique in vitro system in which to further investigate the structural proteins of HCV and to evaluate novel antiviral strategies against hepatitis C in a well-defined and reproducible cellular context.     

Extravesical involvement in patients with bladder carcinoma in situ: biological and therapy implications

PURPOSE: The biological and therapeutic implications of extravesical involvement in patients with bladder carcinoma in situ were analyzed. MATERIALS AND METHODS: Of 138 patients with bladder carcinoma in situ 87 (63%) had extravesical involvement, including the prostate in 53, the upper urinary tract in 11 and both structures in 23 (pan-urothelial involvement). With survival free of disease as an end point, univariate and multivariate analyses were done. RESULTS: Patients with extravesical involvement had worse survival than those with bladder carcinoma in situ alone (p < 0.001). In multivariate analysis prostate involvement (p = 0.0007) and pan-urothelial involvement (p = 0.0001) were selected as significant variables. When pathological patterns were considered prostatic stromal invasion (p = 0.0002) was the only variable selected. With these data 3 patient groups with disease mortality risk were defined. CONCLUSIONS: Prostate involvement and pan-urothelial involvement behave as independent prognostic factors, with the latter probably reflecting an extremetly diffuse character of carcinoma in situ. However, the upper urinary tract had no influence on survival. In patients with upper urinary tract and/or prostatic involvement limited to the mucosa treatment can be conservative. Patients with ductal or stromal involvement should undergo radical treatment. For upper tract involvement conservative approaches may be considered if there are no radiological signs of invasion or low grade tumor.     

Distribution and origin of peptide-containing nerve fibres in the rat and human mammary gland

The structures in the mammary gland involved in milk ejection have been investigated with regard to their relation to different types of peptidergic nerve fibres and their origin. Lactating rats were studied with immunohistochemistry focusing on the nipple, the parenchyma, the mammary blood vessels and the mammary nerve. The human mammary gland was also analysed. In the mammary gland from rat and human, nerve endings in the subepidermis, around smooth muscle cells in the nipple, in the connective tissue surrounding lactiferous ducts and alveoli in the nipple and in the parenchyma of the mammary gland showed immunoreactivity for calcitonin gene-related peptide, substance P, vasoactive intestinal polypeptide, peptide histidine isoleucine, neuropeptide Y, galanin and tyrosine hydroxylase, whereas dynorphin-positive nerve fibres could not be detected. The mammary nerve contained calcitonin gene-related peptide, vasoactive intestinal polypeptide, neuropeptide Y and tyrosine hydroxylase immunoreactivities; the adventitia of the mammary artery contained nerve fibres immunoreactive for neuropeptide Y and tyrosine hydroxylase, while vasoactive intestinal polypeptide-, peptide histidine isoleucine-, calcitonin gene-related peptide- and substance P-positive fibres were found in the tissue surrounding the artery. The wall of the mammary vein had nerve terminals immunoreactive for neuropeptide Y, tyrosine hydroxylase, calcitonin gene-related peptide and substance P. With the help of retrograde tracing using wheat germ agglutinin in combination with immunohistochemistry, projections of calcitonin gene-related peptide-immunoreactive cells in the dorsal root ganglia to the nipple were established. Neurons in the sympathetic stellate ganglion containing neuropeptide Y and tyrosine hydroxylase also projected to the mammary gland. Moreover retrogradely-labelled cells were found in the nodose ganglion, and they were vasoactive intestinal polypeptide-immunoreactive. These results demonstrate a rich distribution of different types of nerve fibres in structures of the mammary gland related to milk ejection. These nerve fibres and their peptides may be involved in the local control of milk ejection.     

On people's understanding of the diagnostic implications of probabilistic data

Two lines of prior research into the conditions under which people seek information are examined in light of two statistical definitions of diagnosticity. Five experiments are reported. In two, subjects selected information in order to test a hypothesis. In the remaining three, they selected information in order to convince someone else of the truth of a known hypothesis. A total of 567 university students served as subjects. The two primary conclusions were as follows: (1) When the task is highly structured by the environment, subjects select information diagnostically, and (2) when the task is less structured, so that subjects must seek relevant information not manifest, they select information pseudodiagnostically. Possible relations to other laboratory inference tasks and to clinical judgment are discussed.     

Comparison of microvascularization in diagnostic needle biopsies and radical prostatectomies in prostate carcinoma

BACKGROUND: Since September 1994 we have administered topical cyclosporin A 2% (CSA) in a prospective study to patients with Thygeson's superficial punctate keratitis (TSPK). After our promising short-term results we now present medium-term data of a larger patient group. PATIENTS AND METHODS: Topical CSA was administered to 52 eyes of 28 patients with TSPK. Forty-two were adult eyes (group I), 10 children's eyes (group II). Starting with 3 drops daily during the 1st month, CSA was reduced to 1 drop every 2nd day within 4 months and stopped after 6 months. RESULTS: Complete suppression of the typical epithelial and supepithelial opacities could be achieved in 71.5% of cases in group I and 40% in group II as long as therapy was administered; the other patients responded only partially or not at all. Recurrences were a problem during tapering off or shortly after cessation of therapy, but they could again be treated effectively with the initial CSA regime. Thirty-one percent of all adult eyes and 20% of all pediatric eyes seemed to have completely healed during the observation time. CONCLUSIONS: In more than two thirds of our adult patients topical CSA 2% suppresses the epithelial and subepithelial opacities for as long as this non-steroid therapy is administered. Definite healing seems to be achieved in almost one third of all adult patients. In another one third, long-term low-dose CSA therapy is necessary before complete healing may be expected. Children probably do not respond to therapy as well as adults. Whereas the only therapeutic alternative, i.e. steroid eye drops, have a significant potential for side effects in the long run, no side effects have been known from low-dose CSA eye drops. We regard CSA eye drops as a significant progress in the symptomatic treatment of TSPK.     

Distribution of normal and abnormal fluid collections in the glenohumeral joint: implications for MR arthrography

OBJECTIVE: This study determined levels of cathepsin D activity in tissue components of normal human ovary to establish a basis for comparison with human ovarian adenocarcinomas. METHODS: Cathepsin D activity per mg tissue, per microgram protein, and per microgram DNA was determined in human ovarian tissues (cortex, follicle, corpus luteum, corpus albicans) from patients of various ages and during the menstrual cycle. Levels of cathepsin D activity were also determined in ovarian adenocarcinomas and other pathologic tissues. RESULTS: Cathepsin D levels (per mg tissue) were significantly greater (P < .001) in ovarian follicle and corpus luteum compared with cortex. Although there was not a clear correlation between enzyme activity in the cortex and day of the menstrual cycle or patient age, levels of enzyme activity appeared to decrease with each parameter. Cathepsin D levels per mg tissue in ovarian adenocarcinoma were 40% higher than in postmenopausal ovarian cortex, but the difference was not statistically significant. CONCLUSION: The diversity of cathepsin D levels in normal ovarian tissue compartments indicates that specific tissues must be used in comparisons with ovarian tumors.     

Measuring serum thyroglobulin in patients with follicular thyroid nodule: its diagnostic implications

To determine the diagnostic implications of measuring the serum thyroglobulin level in patients with a solitary follicular thyroid tumor, a retrospective study was conducted on 122 consecutive patients with a solitary follicular thyroid nodule who underwent thyroidectomy. Data for eight variables were collected: the serum thyroglobulin (Tg) level (microgram/l), age, maximum diameter of the nodule, gender, histopathologic type, presence or absence of metastases, macroscopic characteristics of the cut surface of the resected tumor, and smoking habit. Multiple regression analyses were used to investigate the relationships between the serum Tg level and the seven other variables. The diagnostic value of serum Tg was examined by means of receiver operating characteristic (ROC) curves. There were significant correlations between the serum Tg level and the maximum diameter of the nodule, the macroscopic characteristics, and the smoking habit. The sensitivity and specificity of the serum Tg level with a cut-off value of 1,000 micrograms/l were 57% and 86%, respectively. The likelihood ratio favouring follicular carcinoma associated with the serum Tg > 1,000 micrograms/l was 4.41. Measuring the level of serum Tg may be useful in discriminating follicular carcinoma from follicular adenoma, but since there may be some biases in this retrospective study, the results are less definitive. Further research activities are mandatory to obtain valid evidence.