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PubMed1990

Examination of islets in the pancreas biopsy specimens from newly diagnosed type 1 (insulin-dependent) diabetic patients.

We attempted to examine the immunopathological change of the pancreatic islets of newly diagnosed Type 1 (insulin-dependent) diabetic patients and thereby to obtain useful information for the therapy of the patients. For this purpose, pancreas biopsy under laparoscopy was performed 2-4 months after the onset of Type 1 diabetes in seven newly diagnosed patients. All biopsies were performed safely without any complications. Immunohistochemical examination of the biopsy specimens revealed a marked decrease of insulin-containing cells, preservation of glucagon-containing cells, and various degrees of expression of MHC class I and class II antigens in islet cells and in endothelial cells within and around the islets. Signs of active autoimmune phenomena, e.g. lymphocytic infiltration or immunoglobulin deposition in islets, were not detected in any of these patients by light microscopical evaluation. We conclude that pancreas biopsy under laparoscopy has shown various immunological changes in the islets of newly diagnosed Type 1 diabetic patients. Pancreas biopsy, however, may not be suitable under the present protocol for the selection of patients for immunotherapy because of problems including sampling errors.

Adult↗
PubMed1985

T-cell subsets in multiple sclerosis: lack of correlation between helper and suppressor T cells and the clinical state.

Peripheral blood T-lymphocyte subsets were investigated in a group of 26 multiple sclerosis (MS) patients of different clinical categories and compared to those of 15 normal controls and 7 other patients with known immunoregulatory disorders. In addition 17 well-documented acute relapses in 11 MS patients were also studied, some of whom were tested serially prior to, during, and after the acute attack. Using three different commercial preparations of monoclonal antibodies directed against human T3, T4, and T8 lymphocyte markers, none of the MS patients irrespective of disease category exhibited any changes in the absolute numbers of T-cell subsets or ratios thereof; this was true during either quiescent or active stages of the disease. In contrast, several patients with known immunoregulatory disorders exhibited clear changes in T4/T8 ratios. Factors such as type of patient studied, sampling error, and methods of isolation of mononuclear cells, as well as source of monoclonal antibody, failed to explain the lack of change in T-cell subsets in these patients. Thus, our data fail to confirm the previous reports of a decrease in the absolute numbers of T8 cells or the increase in the T4/T8 ratios in active or quiescent MS patients. These negative findings underscore the need for further studies relating these markers to meaningful functional properties of these cells and their interaction with the relevant target organs.

Adult↗
PubMed1985

Chemical and histochemical studies of normal and diseased human gastrointestinal tract. III. Changes in the histochemical and chemical properties of the epithelial glycoproteins in the mucosa close to colonic tumours.

Histochemical, chemical and histological studies were performed on 26 specimens of human colonic tumours and 62 specimens of mucosa taken at distances of 0.5-5.0 cm from the tumour. The tumour glycoproteins were divided almost equally between three anionic types, sulphomucin, sialomucin and mixed sialomucin and sulphomucin. All showed a reduction in staining for side chain O-acylated sialic acid. In 56% of the tumours, this was accompanied by loss of glycoprotein while, in 44%, abundant mucin was still present. Histochemical examination of the mucosal specimens indicated that in 24.2% the side chain O-acylated sialic acids did not differ from normal. In 41.9% there was a focal change and in 33.9% there was a generalized field reduction in the proportion of side chain O-acyl sialic acids. The latter were subdivided into moderate and severe. Chemical analyses correlated well with the histochemical classification of the mucosal specimens and showed that, on average, the classifications focal and severe field change were not due to sampling error. Forty-five per cent of the cases showed only focal change and 40% only field change. Mucosal specimens associated with 60% of the moderately differentiated tumours showed only focal change while those associated with 75% of well-differentiated tumours showed only field change. Abnormal patterns of staining for side chain O-acylated sialic acids (a) were largely independent of the distance from the tumour, (b) occurred in the presence of a normal pattern of staining for sialomucins and sulphomucins and (c) were associated with 61.4% of the specimens that showed no discernible evidence of histological abnormality. In contrast, only one specimen showed evidence of histological change without a corresponding change in O-acylated sialic acids. The data suggest that abnormal patterns of staining for O-acylated sialic acids may represent premalignant change but their precise significance and specificity requires further studies of non-neoplastic diseases of the colon.

Colonic Neoplasms↗
PubMed1991

Evaluation of potential interactions involving trichothecene mycotoxins using the chick embryotoxicity bioassay.

The Chick Embryotoxicity Screening Test (CHEST) was used to examine possible interactions between different trichothecenes. Combinations of deoxynivalenol (DON), 15-acetyldeoxynivalenol (15-ADON) and HT-2 toxin were tested at various concentrations and the effects were determined based on percent mortality. The combined toxicity of any two trichothecenes was found to be additive. Discrepancies between observed and expected mortality values seldom differed by more than 10%, well within sampling error for the binomial distribution. Several limitations of the CHEST assay are discussed.

Animals↗
PubMed1979

[On the value of drill biopsy in diagnosis of breast lesions (author's transl)].

During a period of 30 months 216 drill biopsies of palpable breast lesions were carried out. By using this method sufficient tissue material for a histological examination could be acquired in all cases. Out of 106 cases, in which the histological results could exactly be proved by following excision biopsy or mastectomy, 87% were correctly diagnosed by drill biopsy. The reason for failure in all of the 14 false drill biopsy diagnoses was due to sampling error. Comparing the diagnostic results of the first 15 month after establishing the method, with the second half of the investigation period, a considerable improvement from 80% to 94% of correct diagnoses could be established. This improvement was based on increasing experience and routine. By means of drill biopsy, cosmetically and diagnostically disturbing scar formation could be avoided. Drill biopsy can be carried out in local anaesthesia and on outpatient basis as well. It is also suitable for frozen-section technique.

Biopsy, Needle↗
PubMed1995

Genetic characterization of geographic populations using morphometrical traits in Drosophila melanogaster: isogroups versus isofemale lines.

Studies of short or medium range geographic variations play an increasing role in ecological genetics, and sensitive techniques are required to detect them. In this respect, two sampling techniques were compared in D. melanogaster. The biological data were provided by the analysis of four natural populations from the same geographic area, Spain (one) and Southern France (three), for four morphometrical traits: abdomen and thoracic pigmentation, and wing and thorax lengths. Traits were measured on wild living females and on their progeny reared in the laboratory at 25 degrees C. For progeny analyses, two techniques were compared: the usual isofemale line technique, sib families issued from a single female, and a new isogroup technique, the progeny produced by a group of 20 wild-collected parents. Large phenotypic variations were observed in wild living flies, corresponding to the unstability of natural environmental conditions during their development. Among laboratory grown flies, variations were much smaller. Between isogroups, differences were small, due to sampling error and some common environment effects. Variations between lines were much greater, thus demonstrating a strong genetic component. When different populations have to be compared, the isogroup technique should be preferred since, for the same amount of work, the lesser variability between groups provides a more precise characterization of the population means.

Animals↗
PubMed1996

Effect of specimen collection techniques, transport media, and incubation of cultures on the detection rate of Helicobacter pylori.

Culture and histologic examination are considered "gold standard" methods for the detection of Helicobacter pylori, but discrepancies may occur with either method. Failure to detect Helicobacter pylori may be due to sampling error, inappropriate transport or culture media, or insufficient duration of the incubation period. Rates of detection of Helicobacter pylori by culture and histopathologic examination of gastric mucosal biopsy specimens were determined in 102 consecutive dyspeptic patients. In a separate group of 60 patients, rates of detection of Helicobacter pylori by culture of antral brushings and the length of incubation required in selective and nonselective culture media were studied. In the first group of 102 patients, the combination of culture and histologic examination detected 54 Helicobacter pylori-positive patients, whereas the separate techniques each detected 51 Helicobacter pylori-positive patients. In the second group of 60 patients evaluated by culture of antral brushings, the rate of detection of Helicobacter pylori was 25 of 60 and was similar for culture (25/60) and histologic examination (25/60). In the second group the length of incubation required to detect Helicobacter pylori was different for selective and nonselective media. In nonselective media, incubation of up to ten days was required to detect all Helicobacter pylori infections, whereas in selective media seven days was sufficient. Rates of detection of Helicobacter pylori by culture, histopathologic examination and culture from brushings were similar, whereas the combination of culture and histopathologic examination achieved a superior rate of detection. The incubation period required for the detection of Helicobacter pylori by culture was a minimum of seven days and was dependent on the culture medium used.

Adult↗
PubMed1985

The diagnostic criteria of myocarditis by endomyocardial biopsy.

The difficulties in diagnosing acute idiopathic myocarditis have been highlighted. Only about 30% of clinically suspected cases show morphologic evidence of an inflammatory infiltrate. Difficulties experienced in obtaining positive results include timing of the biopsy in relation to the acute symptoms of the patient, sampling error, and quantitative criteria. In addition, pressure from the referring physician may influence the pathologic interpretation, i.e., in making a morphologic diagnosis on slender evidence. Caution is also necessary in the interpretation of end-stage disease of dilated cardiomyopathy and "chronic myocarditis." This is important as it influences therapy with immunosuppressive agents. The importance of obtaining a detailed history of drugs to which the patient might have been exposed and can result in myocarditis is also stressed. Only if an accurate and unbiased pathologic evaluation can be made will a prospective, randomized multicenter trial yield useful information. The Dallas Myocarditis Panel has set forth useful criteria and guidelines in an attempt to classify the morphologic diagnosis of myocarditis. Semantic and diagnostic criteria for myocarditis can still be challenged, but the Dallas criteria for evaluation does allow an accurate assessment by all pathologists, in spite of individual variation.

Biopsy↗
PubMed1996

Carcinoma of the rectum. Possible cellular predictors of metastatic potential and response to radiation therapy.

BACKGROUND: Preoperative radiation therapy can markedly improve local control of rectal carcinoma. However, some tumors do not respond well to moderate doses of preoperative radiation and would be better served by more aggressive preoperative treatment (e.g., chemoradiotherapy). Cellular predictors of responsiveness to radiation can help to select lesions for more aggressive treatment. In addition, there is a need for cellular predictors of metastatic potential. This is particularly important in the setting of preoperative radiation-downstaging by preoperative treatment can obscure the true pathologic stage of a tumor and confound the usual selection criteria for postoperative chemotherapy. PURPOSE: This study was undertaken to determine if proliferating cell nuclear antigen (PCNA), p53, DNA ploidy, and S-phase fraction are associated with response to radiation and/or risk for distant metastatic disease and to determine if these cellular markers are best evaluated from preradiation biopsy specimen or the larger (but possibly altered) final surgical specimen. MATERIALS AND METHODS: Archival specimens from 23 cases of ultrasound T3 or T4 rectal carcinoma treated preoperatively with radiation therapy were reviewed. Eligible lesions had preradiation biopsy specimens of sufficient size for flow cytometric review of archival tissue. Factors considered included PCNA positivity, presence of mutant nuclear p53, more than 30 percent tumor cells in S-phase, and presence of aneuploidy. RESULTS: With a median follow-up of three years, overall freedom from relapse was 83 percent, with all but one failure being extrapelvic. PCNA positivity in the preradiation specimen was significantly (P = 0.025) associated with a greater risk of tumor recurrence. In addition, there was a trend to greater likelihood of "probable downstaging" (defined as surgical T stage less than preradiation ultrasound T stage) for lesions that were PCNA-negative or lesions with normal p53. Biomarkers measured in the postradiation surgical specimen were not associated with either freedom from relapse or response to radiation. Radiation treatment appeared to produce false-negatives in the final specimen. Thus, there were significantly more specimens converting from PCNA-positive to PCNA-negative after preoperative radiation than would be expected solely on the basis of sampling errors (P = 0.004). Similar results were found for abnormal p53 findings (P = 0.02). CONCLUSIONS: Prospective studies of biomarkers should be based on pretreatment specimens if preoperative radiation is given. For carcinoma of the rectum, PCNA and p53 may be useful predictors of both metastatic potential and responsiveness to radiation.

Adenocarcinoma↗
PubMed1985

Relationship of flow cytometry results to clinical and steroid receptor status in human breast cancer.

Flow cytometry (FC), estrogen receptor (ER), and progesterone receptor (PR) analyses were performed on 226 breast cancers. The presence of steroid receptors was inversely proportional to proliferative index and percent aneuploidy. Within the two ER (+ and -) groups, the presence of PR did not add significantly to the comparison. The mean proliferative index for the diploid tumors was 17.5 +/- 6.8 compared to 27.8 +/- 9.8 for aneuploid tumors (p less than .001). The degree of aneuploidy, or DNA index, was not related to cell cycle kinetics or steroid receptor status. In 163 tissues analyzed for percent tumor present, a correlation between the relative number of aneuploid cells and percent tumor in the histologic review was observed. A study of the diploid tumors indicated greater than 75% had at least 10% tumor cells by histologic review. Since with FC one can observe at least 10% aneuploid cells in a tumor sample, it is our opinion that the percent aneuploidy in this study is not artifactually low due to sampling error. There was no significant relationship between nodal status or number of positive nodes and proliferative index, aneuploidy, or steroid receptor status. Metastatic tumors had a higher mean proliferative index, but this was not statistically significant. There was a relationship between age and proliferative index but not between age and ploidy status. In a small group of patients there was a trend for proliferative index and percent aneuploidy to be higher in the poorly differentiated and larger tumors when compared to the well differentiated and smaller tumors.

Age Factors↗
PubMed1999

Negative genetic test result in familial adenomatous polyposis: clinical screening implications.

PURPOSE: The goal of genetic testing is to define individual risk, which in turn may guide clinical management. METHODS: Thirty-two international familial adenomatous polyposis registries were surveyed regarding their approach to a specific clinical management question. There were 30 respondents. Respondents declared their clinical policy for an at-risk, first-degree relative who undergoes direct mutation analysis and does not have an APC gene mutation known to be present in his or her family. RESULTS: Nineteen of 30 (63.3 percent) registries would discharge this negative APC mutation case from clinical screening. Eleven of 30 (37 percent) registries would maintain clinical screening. Reasons offered for maintaining surveillance included the need for additional confirmation of the APC mutation in two affected relatives, the possibility of sampling error or two different mutations in an affected family, limited prospective data, and patient anxiety. CONCLUSIONS: The discrepancy in response to the survey suggests that some clinicians are as yet reluctant to accept fully that predictive genetic analysis is a definitive guide to clinical management in familial adenomatous polyposis. Nevertheless, we believe that use of a predictive gene test for familial adenomatous polyposis should alter management, decrease cost, and reduce psychological trauma for the tested individual. Although the benefit of APC analysis is accepted for the positive gene carrier, the challenge remains to reclassify the negative gene carriers who are no longer at risk for familial adenomatous polyposis.

Adenomatous Polyposis Coli↗
PubMed2000

Validation of real-time continuous perfusion measurement.

Perfusion, the rate at which blood in tissue is replenished at the capillary level, is a primary factor in the transport of heat, drugs, oxygen and nutrients. While there have been many measurement techniques proposed, most do not lend themselves to routine, continuous and real-time use. A minimally invasive probe, called the thermal diffusion probe (TDP), which uses a self-heated thermistor to measure absolute perfusion continuously and in real time, was validated at low flows with the microsphere technique. In 27 rabbits, simultaneous TDP measurements were made in liver from 0 to 60 ml min-1 100 g-1. The TDP perfusion correlated well with the microspheres (R2 = 0.898) and the agreement between techniques is very good with a slope close to unity (0.921) and an intercept close to zero (0.566 ml min-1 100 g-1). Variability between the two techniques was primarily due to the sampling error from the microsphere 'snap shot' of periodic blood flow when compared with the continuous TDP perfusion measurement. The ability to quantify local perfusion continuously and in real time may have a profound impact on patient management in a number of clinical areas such as organ transplantation, neurosurgery, oncology and others, in which quantitative knowledge of perfusion is of value.

Animals↗
PubMed1982

Quantitative bone histology in 84 normal American subjects. Micromorphometric analysis and evaluation of variance in iliac bone.

Quantitative bone histology was done in undecalcified sections of iliac crest bone specimens obtained from 84 normal American individuals. Samples were obtained within 12 h after death in a vertical and horizontal manner from both the right and left iliac crests. In addition to the determination of normal values of micromophometric parameters of bone in these healthy American subjects, the following studies were carried out: (a) comparison of variance of micromorphometric parameters of bone obtained from the right versus left iliac bone (40 pairs), (b) comparison of micromorphometric parameters of bone obtained in a vertical versus horizontal manner (12 pairs), (c) evaluation of variance with increasing distance from the compact zone in bone samples obtained in a vertical manner (44 pairs), (d) analysis of variation between bone samples obtained more anteriorly versus posteriorly along the iliac crest (N = 40), (e) comparison of differences in micromorphometric parameters obtained from age-matched men versus premenopausal women (N = 12), and (f) plotting of histograms for assessment of distribution of micromorphometric parameters. The results show that histomorphometric data of bone cannot be easily compared when different techniques are employed for obtaining bone samples. Sampling variations are kept smaller when bone specimens are obtained in a vertical manner. Anterior/posterior variation does not cause major sampling error. If ranges of variation are taken into account, quantitative bone histology is a valuable tool for assessment of bone structure and bone cells.

Adolescent↗
PubMed1997

Feasibility of diagnosing chronic myocarditis by endomyocardial biopsy.

In studies of all the layers of autopsied hearts from patients with chronic myocarditis, local clusters of lymphocytes are frequently noted, in contrast with hearts obtained from patients with acute myocarditis. Myocardial biopsy specimens, however are no larger than about 2mm x 3mm. With this in mind, the present study was undertaken to determine whether chronic myocarditis can be diagnosed by endomyocardial biopsy. Specimens were obtained from seven patients in whom chronic myocarditis was confirmed by the clinical course and by autopsy findings. In H&E stained specimens, sites corresponding to the biopsy sites in both ventricles (right ventricular free wall, right ventricular side of the ventricular septum, left ventricular lateral wall) were selected at random (five sites each from the right and left ventricles in each patient) and examined under a light microscope. A mean of 5 or more lymphocytes per visual field (by light microscopy at 400-fold magnification), a proposed quantitative diagnostic criterion of myocarditis, was noted in the right ventricle in three patients (5 lymphocytes in two patients and 6 in one patient) and in the left ventricle in one patient (5 lymphocytes). Also, when the presence of lymphocyte clusters, considered to be a characteristic feature of chronic myocarditis, was determined, clusters of 20 or more lymphocytes per visual field were found in the same patients as those mentioned above, namely, in three patients (42.8%) in the right ventricle, as mentioned above, and in one patient (14.3%) in the left ventricle. At the sites of these lymphocyte clusters. findings such as degenerative changes of the myocardial cells and interstitial fibrosis were also associated, making possible a diagnosis of myocarditis. Therefore, in chronic myocarditis, even if five specimens are obtained by right ventricular biopsy, in approximately one half of patients the diagnosis of chronic myocarditis will be missed because of sampling errors.

Adolescent↗
PubMed1983

Prognostic significance of bridging necrosis in chronic active hepatitis.

A retrospective study of 307 patients with chronic active hepatitis (CAH) was conducted to assess the prognostic significance of bridging necrosis (BN). BN was encountered in 70 (22.8%) of 307 patients with CAH. Twenty six cases of CAH with BN and 40 of CAH without BN were followed up with repeated liver biopsies for periods of from 6 months to 12 years. Twelve (46.1%) of the 26 CAH cases with BN developed cirrhosis including 4 cases of early cirrhosis. Seven cases had no sequential histologic changes. Histologic improvement to CAH or to chronic inactive hepatitis (CIH) was seen in 3. On the other hand, one (2.5%) of 40 CAH cases developed cirrhosis and 3 early cirrhosis. Another 3 cases histologically showed aggravation to CAH with BN, two of which developed in a short period after the initial biopsy and the possibility of sampling error in the initial biopsy cannot be ruled out. There were no sequential histologic changes in 26 of the 40 cases. Histologic improvement to nonspecific reactive hepatitis or to CIH was seen in 7. From these findings, it may be concluded that the presence of BN in CAH holds prognostic implications.

Adolescent↗
PubMedDate not supplied

Immunohistochemical techniques for the demonstration of viral antigens in liver tissue.

Liver biopsy specimens from patients positive for serum HBsAg reveal various expression patterns when properly stained by immunohistochemical techniques for the demonstration of HBsAg, HBcAg and HDAg. A negative staining for these three antigens seems to be associated with two conditions, i.e., self-limiting acute lobular hepatitis (ALH) or low amounts of intrahepatic antigens. The discrepancy between serum positivity and tissue negativity for HBsAg can be explained either by sampling error or by the higher sensitivity of the radioimmunoassay as compared with immunohistochemical methods. The use of amplification systems such as the avidin-biotin-peroxidase complex enhances the sensitivity of immunohistochemical peroxidase-antiperoxidase (PAP) techniques and makes it possible to detect very small amounts of both HBsAg and HBcAg in liver cells from paraffin-embedded tissue sections which had been negative with the conventional PAP technique. In cases with a positive staining for viral antigens, two main expression patterns (non-aggressive and aggressive) can be distinguished. The non-aggressive pattern is reflected in the HBcAg-free HBsAg-positive type (HBsAg carrier) or the generalized type of nuclear core (HBcAg carrier), while the aggressive pattern is reflected in the presence of HDAg, the presence of HDAg and HBcAg, the focal type of nuclear core or the cytoplasmic HBcAg. Superinfection of HBsAg carriers or switching from generalized to focal core, with or without cytoplasmic expression of HBcAg, results in transition from non-aggressive to aggressive pattern. The aggressive pattern occurs in association with histological features of chronic active hepatitis (CAH). When it occurs in ALH cases or in milder forms of chronic hepatitis, an evolution into CAH has to be expected. Features of severe CAH, eventually with cirrhosis, are found in association with two new expression patterns: the cytoplasmic core and the simultaneous presence of HBcAg and HDAg. When features of CAH are observed in liver tissue specimens with HBcAg-free HBsAg-positive type, the liver disease may be due to viral superinfection or to non-viral etiology, e.g., alpha 1-antitrypsin deficiency.

Hepatitis B Antigens↗
PubMed1982

Estrogen receptors in human breast cancer. II. Correlation between the histochemical method and biochemical assay.

The present study defines criteria for determining the presence of estrogen-receptors in human breast carcinomas demonstrated by a histochemical assay using 17 beta-estradiol-carboxy-methyl-oxim-bovine serum albumen-FITC. The criteria were: 1) the percentage of cells showing fluorescence; 2) the intensity of the fluorescence observed, and 3) the percentage of epithelial structures in tissue specimens. Using these predefined criteria in 132 human breast carcinomas as 91.6% agreement was found between the results of the histochemical assay and those of the biochemical Charcoal method. The main causes of disagreement (7 of the 11 cases) were sampling errors between the tissue specimens used for the histochemical and biochemical assay, and an insufficient percentage of epithelial structures (less than 15%) to allow biochemical identification of estrogen receptor activity. In the hands of pathologists with experience of the field of histochemistry this histochemical assay may be the method of choice for the assessment of estrogen receptors.

Adult↗
PubMed1998

Conflict among individual mitochondrial proteins in resolving the phylogeny of eutherian orders.

The phylogenetic relationship among primates, ferungulates (artiodactyls + cetaceans + perissodactyls + carnivores), and rodents was examined using proteins encoded by the H strand of mtDNA, with marsupials and monotremes as the outgroup. Trees estimated from individual proteins were compared in detail with the tree estimated from all 12 proteins (either concatenated or summing up log-likelihood scores for each gene). Although the overall evidence strongly suggests ((primates, ferungulates), rodents), the ND1 data clearly support another tree, ((primates, rodents), ferungulates). To clarify whether this contradiction is due to (1) a stochastic (sampling) error; (2) minor model-based errors (e.g., ignoring site rate variability), or (3) convergent and parallel evolution (specifically between either primates and rodents or ferungulates and the outgroup), the ND1 genes from many additional species of primates, rodents, other eutherian orders, and the outgroup (marsupials + monotremes) were sequenced. The phylogenetic analyses were extensive and aimed to eliminate the following artifacts as possible causes of the aberrant result: base composition biases, unequal site substitution rates, or the cumulative effects of both. Neither more sophisticated evolutionary analyses nor the addition of species changed the previous conclusion. That is, the statistical support for grouping rodents and primates to the exclusion of all other taxa fluctuates upward or downward in quite a tight range centered near 95% confidence. These results and a site-by-site examination of the sequences clearly suggest that convergent or parallel evolution has occurred in ND1 between primates and rodents and/or between ferungulates and the outgroup. While the primate/rodent grouping is strange, ND1 also throws some interesting light on the relationships of some eutherian orders, marsupials, and montremes. In these parts of the tree, ND1 shows no apparent tendency for unexplained convergences.

Animals↗