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Biomedical subjects

J Esser

Publications and source records attributed to J Esser.

At least 19 recordsLinked to original sources
PubMed1994

Large platelets continue to circulate in an activated state after myocardial infarction.

This study was intended to investigate the actual platelet activation status after an acute coronary event. The activation status of circulating platelets was assayed directly by measuring the membrane activation markers CD62 and CD63 with the Düsseldorf III flow cytometry test in 22 patients with the diagnosis of acute myocardial infarction during the 48-h observation period following the acute event. The number of activated, marker-positive sample platelets was significantly increased in the post-MI patients: CD62: 5.8% x 2.25 +/- 1 vs. 3.5% x 2.32 +/- 1, P < or = 0.05; CD63: J8.7% x 1.77 +/- 1 vs. 4.6% x 2.16 +/- 1, P < or = 0.00.1. The platelet volume and count were concomitantly increased (12.1 +/- 2.4 fl/ 236 +/- 90 x 10(3) microliters-1 compared to 8.3 +/- 1.6 fl/ 187 +/- 42 x 10(3) microliters-1) in the control group. Particularly large platelets were identified as being activated documented by the exponential increase in the difference in CD63-binding sites per sample platelet above the 90%-percentile and below the 10%-percentile of the volume distribution: delta + 1341 +/- 903 (MI patients) vs. delta + 276 +/- 126 (controls), P < or = 0.00.1. Significant creatine kinase elevation and decrease in platelet count was found in the non-survivor subset (n = 5). We conclude that predominantly large platelets continue to circulate in an activated state after MI. This study provides direct evidence that the assumption of an increased thrombotic potential becomes operative in vivo in MI patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Distal splenorenal shunt for non-cirrhotic variceal bleeding in black South Africans.

Distal splenorenal shunt (DSRS) is a once-only form of treatment. It is suitable for many black South Africans with non-cirrhotic variceal bleeding who cannot attend repeated follow-up sclerotherapy sessions. However, persistent hyperbilirubinaemia and encephalopathy may occur following DSRS in schistosomiasis. Forty-one consecutive patients with DSRS have been treated over a 7-year period. The causes of portal hypertension were schistosomiasis (32), portal vein thrombosis (8) and diffuse nodular hyperplasia (1). Operative mortality was 6%. Encephalopathy was observed in 1 patient. Galactose elimination capacity (GEC) and technetium-diethylenetriamine penta-acetic acid hepatic perfusion index (HPI) were used to assess liver function and hepatic perfusion pre- and postoperatively, respectively, in schistosomiasis. GEC was 348 +/- 37 (M +/- SD) before, compared with 343 +/- 67 postoperatively (P = 0.78). HPI showed long-term preservation of hepatopetal portal venous flow following DSRS. Morbidity and mortality were observed only in patients with schistosomiasis associated with hepatitis B chronic active hepatitis. DSRS is ideal treatment in selected patients with non-cirrhotic variceal bleeding.

Adult↗
PubMed1991

Circulating activated platelets in myeloproliferative disorders.

Platelet activation in patients with myeloproliferative disorders is often suggested by increased platelet alpha-granule secretion and an acquired storage pool defect of dense granules. To determine whether activated platelets circulate in patients with chronic myeloproliferative disorders, we evaluated the binding of monoclonal antibodies against activation-dependent epitopes on resting platelets (P 12, CD 63, and CD 62) in 12 patients with prominent megakaryocytic proliferation (8 patients with essential thrombocythemia, 2 with chronic myeloid leukemia, and 2 patients with polycythemia rubra vera). In addition, platelet aggregation in response to collagen, adenosine diphosphate, platelet activating factor, and agglutination with ristocetin was investigated. In 3 patients there was an increased percentage of platelets binding at least 1 activation marker. In 2 other patients, a trend towards increased antibody binding was observed. Binding of the antibody to thrombospondin (P 12) was related to expression of the GMP 140 protein (CD 62, r = 0.76, p = 0.004). There was no correlation of platelet aggregation defects in vitro to increased expression of platelet activation markers or to thrombohaemorrhagic complications. However, circulating activated platelets were detected in three out of five patients with a history of bleeding or thrombotic complications. The results of this preliminary study suggest that some but not all patients with myeloproliferative disorders showed increased amounts of circulating activated platelets. The relation of bleeding and thrombotic complications to the expression of activation-dependent epitopes on platelets in myeloproliferative disorders requires further investigation.

Adult↗
PubMed1991

The effect of direct selection and circular scanning on visual sequential recall.

The purpose of this study was to investigate the influence of selection techniques on visual sequential recall. Specifically, this study investigated whether there are visual sequential recall differences between direct selection and scanning in task performance in normally developing 4-year-old children. Results suggested that there were no significant differences between direct selection and scanning for visual sequential recall. However, subjects correctly recalled significantly fewer symbols in a specific sequence represented by Blissymbols than by Picsyms. In addition they recalled significantly fewer three-symbol sequences than two-symbol sequences regardless of the type of symbol set.

Analysis of Variance↗
PubMed1991

Large platelets circulate in an activated state in diabetes mellitus.

Diabetes mellitus is associated with aggravated development of vascular complications. Yet, it has not been established whether platelet hyperreactivity contributes as a pathogenetic factor. In order to study the role of activated platelets in diabetes mellitus, we investigated the expression of the membrane activation markers CD63 (GP53) and CD62 (GMP-140) as direct indicators of in vivo activation. The CD63-positive fraction was significantly higher in patients (6.1% X 3.7 +/- 1) than in controls (2.7% X 3 +/- 1). In parallel, the CD62-positive fraction was significantly elevated in patients to 5% X 2.5 +/- 1 in comparison to controls (3% X 2 +/- 1). Patients with angiopathy had a mean increase of 304% in CD63-positive and of 223% in CD62-positive platelets. Patients without clinically detectable angiopathy showed a trend to an increased fraction in CD63-/CD62-positive platelets. There was no correlation of the activation markers with fasting blood glucose, HbA1 or platelet count. CD63 platelet bound fluorescence significantly increased with platelet size in the patient group. We conclude that in diabetes mellitus an increased number of large platelets circulate in an activated state predominantly in patients with angiopathy. This could imply that platelets become activated by vascular lesions. The trend in patients without vascular disease, however, suggests that activated platelets may also basically contribute to the prethrombotic state in diabetes mellitus.

Adult↗
PubMed1991

[A new simple test for quantitative determination of near aniseikonia].

A quantitative test for the measurement of near distance aniseikonia is presented which is easy to handle. It combines the advantages of the Awaya near distance test with those of the Aulhorn phase difference haploscope: On the one hand the test can easily measure aniseikonia without a large apparatus, on the other hand it allows an exact comparison of the test objects due to the free mobility of the test objects. This is important because of the frequently accompanying motility disorders.

Aniseikonia↗
PubMed1991

Determination of platelet activation by assaying filamentous actin and detecting membrane alterations.

Thrombin stimulation of human gel-filtered platelets in an unstirred system (without aggregation) results in actin polymerisation. Concomitantly with actin polymerisation the activation markers (CD 63--glycoprotein 53, a 53 kD lysosomal protein and CD 62--GMP 140, a 140 kD alpha granule protein) increase on the platelet membrane as well as the specific binding of monoclonal antibodies to thrombospondin (P 10). Consequently, both assays run in parallel and indicate sensitively platelet activation. Our data also indicate that exposure of subcellular structures following granule fusion is a very early event when platelets are challenged by thrombin and involve a reorganisation of cytoskeletal structures. Cytochalasin E inhibits completely the thrombin-induced actin polymerisation and the platelet aggregation but only partially the thrombin-induced exposure of CD 63. The activation markers CD 62 and P 10 were not influenced.

Actins↗
PubMed1991

[Development of postoperative motility in orbital floor, zygomatic and mid-face fractures].

A prospective study of was made on 100 patients with fractures of the orbital floor, the zygoma and/or midface who were surgically treated and investigated (before and 3 days, 7 days, 1 month and 6 months after surgery) with regard to their eye motility (Hess screen) and their double vision (Harms tangent screen). Stable results were obtained at least 30 days after surgery. Patients in whom early surgery was performed (within 7 days after trauma) showed better results (82% improvement) compared with those operated on in the second week after the trauma (50% improvement) or later (27% improvement). Young patients (less than 10 years of age) and patients with midface fractures (LeFort II and III) showed significantly poorer results with regard to eye motility.

Adolescent↗
PubMed1990

Flow-cytometric detection of surface membrane alterations and concomitant changes in the cytoskeletal actin status of activated platelets.

Occlusive vascular diseases are promoted by a "prethrombotic state" with increased platelet activity. Polymerization of cytoskeletal proteins and exposure of subcellular structures or rebinding of secreted proteins have been characterized as early reactions after platelet activation preceding adhesion and aggregation. Here, we demonstrate the kinetic increase in specific binding of monoclonal antibodies to thrombospondin (P10) and to platelet membrane activation markers CD63 (GP53, a 53 kD lysosomal protein) and CD62 (GMP140, a 140 kD alpha granule protein) by using a flow-cytometric bio-assay and the related change in the actin status by using the DNase-I inhibition assay after stimulation of normal human platelets with 0.2 U/ml thrombin. F-actin was raised from 41% to 51% of total platelet actin content 30 s after stimulation and remained thereafter constant (50% at 60 s). Simultaneously, the percentage of P10, CD63, and CD62 positive platelets was elevated from 5.4%, 24.4%, and 9.1% to 67.4%, 80.2%, and 82.3% respectively. The mean number of P10, CD63, and CD62 antibody binding sites increased from 3,300, 1,715, and 2,146 to 6,400, 6,800, and 9,016 per platelet. Conclusively, changes in the organization of the cytoskeletal protein "actin" and exposure of subcellular structures indicating platelet secretion can be regarded as markers of early platelet activation. Thus, the parallel response in both analytical systems provides further support for the diagnostic concept of flow-cytometric detection of preactivated platelets in the peripheral blood by using fluochrome staining procedures detecting activation dependent structural alterations directly at the cellular level.

Actins↗
PubMed1990

New therapeutic approaches in thyroidal autoimmune diseases.

Antithyroid drugs (AD) still represent the most widely chosen therapy for hyperthyroidism of Graves' disease. Since their interaction with iodine is still poorly understood, this was addressed in multicenter clinical trials. The interaction of iodine and methimazole was studied in 260 patients from iodine deficient countries. Whereas patients with very low iodine supply needed low doses of methimazole, patients with even slightly increased iodine supply needed high doses of methimazole to remain euthyroid. In another study of 1256 patients side effects of AD were shown to be dose-dependent. Immunological markers of thyroid autoimmunity disappear in most patients during treatment with AD although with many exceptions. Remissions after treatment with AD may represent disease heterogeneity within a spontaneous disease course and the spectrum of relapsing hyperthyroidism over euthyroidism to hypothyroidism. Lastly therapeutic strategies in thyroid eye disease have not provided evidence which therapy is superior.

Antithyroid Agents↗
PubMed1990

Estimation of PR and ER by immunocytochemistry in breast cancer. Comparison with radioligand binding methods.

Immunocytochemical assays for progesterone receptor (PR) using monoclonal antirabbit PR antibodies (PR-ICA) and for estrogen receptor (ER) (ER-ICA) were compared with radioligand binding (dextran-coated charcoal [DCC]) methods for receptor determination in patients with breast cancer. Immunocytochemical staining for PR was exclusively nuclear in localization. In this regard, PR staining is similar to previous findings for ER; PR-ICA showed a sensitivity of 89% and specificity of 100%. ER-ICA was also 89% sensitive and similarly specific. There was good correlation between the degree and intensity of staining and quantitative binding of radioligand. Receptor-positive tumors, however, show considerable variation of immunocytochemical staining, suggesting heterogeneity of cellular PR content. The availability of an immunocytochemical assay for PR increases the discriminatory potential for these methods of receptor determination.

Adult↗
PubMed1989

The use of a monoclonal antibody against alpha-fetoprotein for the radioimmunodetection of hepatocellular carcinoma.

The purpose of this study was to investigate the use of a radiolabeled mouse monoclonal antibody (and its F(ab')2 fragment) against alpha-fetoprotein in the scintigraphic diagnosis of hepatocellular carcinoma. Twenty-six southern African Blacks and one Caucasian with hepatocellular carcinoma and four patients with other malignant tumors of the liver were studied. Although six hepatocellular carcinomas appeared to selectively concentrate alpha-fetoprotein antibody, one of these tumors was not producing alpha-fetoprotein. Moreover, in another 18 patients with alpha-fetoprotein-producing hepatocellular carcinomas, uptake of alpha-fetoprotein antibody was at best only equal to that in nontumorous hepatic tissue, and three hepatocellular carcinomas that were not producing alpha-fetoprotein concentrated the antibody to the same extent as did the alpha-fetoprotein-producing tumors and hepatic tissue. All four tumors other than hepatocellular carcinoma concentrated alpha-fetoprotein antibody as well as did hepatic tissue. These findings suggest that the penetration of hepatocellular carcinomas by alpha-fetoprotein antibody is a passive and nonselective process. This conclusion is supported by an in vitro study in which a non-alpha-fetoprotein-producing hepatic metastasis took up as much radiolabeled alpha-fetoprotein antibody as did three of four alpha-fetoprotein-producing hepatocellular carcinomas. A likely explanation for the failure of alpha-fetoprotein monoclonal antibody to be selectively concentrated by hepatocellular carcinomas is that alpha-fetoprotein is an export protein and is not expressed on the cell membranes of malignant hepatocytes.

Adult↗
PubMed1989

[Acute psychosis caused by poisoning with cyclopentolate].

The authors report on a 17-year-old female patient who suffered an acute psychotic attack after local application of cyclopentolate 1.0% in both eyes. The literature is reviewed with regard to systemic side effects of local application of cyclopentolate. Toxicity of cyclopentolate may be found in every age group even if tolerated without side effects before and it has no specificity for patients with certain (especially brain) diseases. The rapid short-term cycloplegic effect and the rare cases of systemic toxicity support the authors opinion that cyclopentolate is a very useful and well-tolerated diagnostic substance.

Adolescent↗
PubMed1989

Post-traumatic parotid fistulae and sialoceles. A prospective study of conservative management in 51 cases.

The management of parotid sialoceles and fistulae have been unsatisfactory in the past, and numerous methods of treatment with varying success and morbidity have been described. The present prospective study reports results of conservative therapy in 51 patients over a 3-year period. In 50 patients, the injury healed upon conservative management. During the early phase of the study, a limited conservative regimen through which the patients received nothing orally for 5 days only was used. During the latter part of the study, patients were administered nothing orally until complete healing of the injury. In terms of the time it took for healing of the injury, the differences of the two regimens (24 +/- 4 vs. 9.4 +/- 0.9 days) was highly significant (p less than 0.001). The response to conservative management depended on the severity of injury as demonstrated by sialography. Injury to minor intraparotid ducts (G1) healed in significantly less time compared with that to a major intraparotid duct (G2) or ductal injuries (p less than 0.001). There was no difference between the healing of G2 injury (10.3 +/- 1.8 days) and partial ductal transections (10.5 +/- 2.2 days) (p greater than 0.05). There was a significantly greater delay in healing with complete duct transections (21.5 +/- 3.7 days) compared with partial duct transections and G2 injuries (10.2 +/- 2.1 days) (p less than 0.01). There was no difference in the mean period for healing between salivary fistulae and sialoceles (p greater than 0.05). It is concluded that a new classification of parotid fistulae based on sialographic findings has prognostic and therapeutic value. Furthermore, the excellent results achieved with conservative therapy in this study suggest that it may be the initial treatment of choice for parotid fistulae.

Acute Disease↗
PubMed1989

Technetium-pertechnetate uptake by ectopic antral mucosa. An experimental study.

The ability of ectopically placed fundic mucosa and retained antral mucosa to concentrate technetium has previously been demonstrated. The ability of ectopically placed antral mucosa to concentrate technetium was investigated. The denervated antrum implanted into the colon concentrated technetium in 5 dogs. However, this response was significantly less than that of parietal cell-containing mucosa (P less than 0.005) of the stomach. Technetium scanning may be useful in detecting ectopic and retained antral mucosa.

Animals↗
PubMed1988

Management of gastric emptying disorders following the Roux-en-Y procedure.

In 46 patients with gastric resection and Roux-en-Y gastrojejunostomy, gastric emptying was studied with the gamma camera. Seventeen patients were free of symptoms, 11 vomited occasionally (less than 5 times weekly), and 18 were severely incapacitated with daily vomiting, weight loss, and bezoar formation. Patients with occasional vomiting had early rapid emptying similar to that seen in the patients who were without symptoms and responded satisfactorily to nonsurgical therapy. The 18 patients with severe vomiting showed a marked delay in the emptying of the solid meal (p less than 0.01) but normal emptying of the liquid. There was no difference between those with and those without stomal ulceration or stomal stenosis. The stasis occurred in the stomach and not in the Roux limb. All 18 patients had a further extensive gastric resection, leaving a 50 to 75 ml upper gastric remnant drained by Roux-en-Y gastroenterostomy. Fifteen of these patients showed improvement and gained weight, and the gastric emptying of both the solid and liquid test meals is now faster than in any of the other groups (p less than 0.03). We conclude that extensive gastric resection is an effective means to reduce symptoms and improve gastric emptying in selected patients with severe gastric stasis of solid food after the Roux-en-Y procedure.

Anastomosis, Roux-en-Y↗