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Biomedical subjects

J Marrink

Publications and source records attributed to J Marrink.

At least 37 records · Page 2Linked to original sources
PubMed1990

Alpha-fetoprotein-lectin binding as a marker of tumour activity or liver damage.

To establish whether alpha-fetoprotein (AFP) produced in the early post-treatment phase of a patient with a germ cell tumour of the testis or the ovary originates from the tumour or is due to an underlying disturbance in liver function, the binding of AFP to concanavalin A (Con A) was investigated as a discriminative variable. A two-step assay is described that can distinguish the type of AFP produced at levels as low as 10 ng/ml. A Con A-binding ratio of 12-43% was found in the patients with disseminated germ cell tumours and in patients with AFP-positive gastrointestinal carcinomas. AFP from the liver gives ratios below 10%.

Biomarkers, Tumor↗
PubMed1989

Complement activation during an active cytomegalovirus infection after renal transplantation: due to circulating immune complexes or alternative pathway activation?

In 32 patients with a renal allograft, serial determinations after transplantation were made of C3d, the stable conversion product of the complement factor C3, as well as serial measurements of the anaphylatoxin C3a des arg. Furthermore, serial determinations were made on the presence of circulating immune complexes using three different assays (C1q binding assay, polyethylene glycol precipitation test, and indirect granulocyte phagocytosis test). Twenty patients were studied during an active cytomegalovirus (CMV) infection, and 12 patients were studied during allograft rejection or during stable phase after renal transplantation. In 12 patients with a CMV infection serial measurements were made of AP50 (alternative pathway of complement). During an active CMV infection elevated C3d as well as elevated C3a des arg levels were found and not in the control group (P less than 0.01). In 8 out of the 12 patients tested, with CMV infection, a decreased hemolytic activity of the alternative pathway (AP50) was found, together with the elevated levels of C3d and C3a des arg. Serum C4 levels were normal or high during CMV infection. Furthermore, circulating immune complexes were found to be positive in 15 out of the 20 patients with a CMV infection (both primary and secondary infections), and in 2 out of 12 patients of the control group. The complement activation found in the CMV group was not related to the presence of circulating immune complex-like material, since complement activation was present in advance of the appearance of the immune complexes, suggesting that complement activation was not due to classical pathway activation by those complexes. We conclude that our data are consistent with complement activation and the formation of biologically active peptides like C3a des arg in patients with an active CMV infection. The decreased hemolytic activity of the alternative pathway (AP50) together with the normal or high C4 levels suggest involvement of the alternative pathway, although further studies of the alternative pathway of C are warranted to confirm this hypothesis.

Adolescent↗
PubMed1988

Results of adjuvant surgery in patients with stage III and IV nonseminomatous testicular tumors after cisplatin-vinblastine-bleomycin chemotherapy.

From January 1978 to April 1983, 53 patients were treated with cisplatin-vinblastine-bleomycin chemotherapy because of advanced nonseminomatous testicular tumor (NSTT). After the chemotherapy, the serum tumor markers were back to normal in 41 patients, of whom 35 were eligible for surgical removal of the residual tumor. In four patients, vital tumor tissue was found in the residual tumor. Salvage chemotherapy resulted in complete remission. Residual mature teratoma was encountered after the chemotherapy in 15 of the 25 patients with a teratomatous component and in one of the ten patients without a teratomatous component in the primary tumor. On completion of the study, 38 of the 53 patients (72%) are still alive, with a median follow-up of 65 months. Subdivided by tumor volume, survival is found to amount to 92% for small-volume disease, 67% for large-volume disease, and 64% for very-large-volume disease. Six patients (11%) developed a recurrence in the course of the follow-up. Exploratory laparotomy after remission induction chemotherapy is necessary in all patients with a teratomatous component in the primary testicular tumor who have become tumor marker negative, irrespective of the roentgenographic findings of the retroperitoneum. Patients without a teratomatous component in the primary tumor should have exploratory laparotomy only in case of roentgenographic evidence of retroperitoneal residual tumor. A thoracotomy is needed only in the presence of roentgenographic evidence of pulmonary residual lesions.

Adolescent↗
PubMed1988

Double cryoprecipitated factor VIII concentrate from heparinised plasma and its heat treatment.

In an attempt to implement the small pool concept in Factor VIII purification, cryoprecipitate derived from heparinised plasma was reprecipitated in the cold providing a factor VIII concentrate for freeze drying and heat treatment. There was considerable purification; only 1% of the original plasma proteins was left in the final product. Factor VIII:C concentration was about 19 IU/ml. Factor VIII related antigen (RAg) appeared heterogeneous, with a broad base and asymmetry on crossed immunoelectrophoresis. Fibrinogen content was 15 g/l. In contrast to high-purity commercial concentrates, fibronectin was considerably concentrated. Immunoglobulin contents were similar to a high-purity commercial product. The amount of other plasma proteins was very small, varying from less than 0.2% for C3 complement to 2.3% ceruloplasmin. In some respects the preparation may be considered as an intermediate-purity Factor VIII concentrate. Following addition of 2% sucrose before freeze drying, Factor VIII, total protein and fibrinogen remain virtually stable (less than 15% loss) during heating of the material to 60, 64 or 68 degrees C for 24 to 72 h without changes of protein spectrum following heating. The heated product when stored at 4 degrees C remains stable for at least 3 months. In two severe haemophiliacs receiving this heat treated product, in vivo Factor VIII recovery was 100% with a mean half life of 10.2 h.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Quantitation of IgM, IgA and IgG rheumatoid factors by ELISA in rheumatoid arthritis and other rheumatic disorders.

We describe the evaluation of an enzyme-linked immunosorbent-assay (ELISA) for the measurement of IgM, IgA and IgG rheumatoid factor (RF). Results were obtained from sera of normal controls and patients with different rheumatic disorders in a cross-sectional study. Both human and rabbit IgG could be used as antigen in the assays. IgA-RF and IgG-RF were measured after pepsin digestion. The WHO reference preparation was used to standardise IgM-RF, but could not be used in the IgA- and IgG-RF assay, because neither IgA- nor IgG-RF could be detected in this standard serum. The ELISA for detection of RF is a highly sensitive and reproducible method and quantitation of results can be standardised. It yields good discriminative values for RA versus controls, in particular when more RF-isotypes are determined. In RA patients a correlation between IgM-, IgA- and IgG-RF concentrations does exist, although a wide variation was found in the ratio of these concentrations.

Adult↗
PubMed1987

Orchidectomy alone in stage I nonseminomatous testicular germ cell tumors.

Fifty-four patients with Stage I nonseminomatous testicular germ cell tumors (NSTGCT) were treated from 1982 to 1984. In 1982 and 1983, the orchidectomy was followed by an exploratory laparotomy to conclude the dissemination study. In 1984, laparotomy was performed only if indicated. The mean follow-up was 29 months. A relapse occurred in 11 patients (20%). The relapse rate in patients who underwent exploratory laparotomy was as high as that in patients who did not. All patients treated for relapse by chemotherapy and surgery entered a complete remission for at least 1 year. It proved impossible to establish criteria for prediction of a subsequent relapse. Both serum tumor marker assays and roentgenography are important aids in diagnosing a relapse. With careful follow-up of Stage I NSTGCT patients, a wait-and-see attitude can be adopted until a relapse occurs.

Humans↗
PubMed1986

Wait-and-see policy in clinical stage I non-seminomatous germ cell tumors of the testis.

Thirty-three patients with a non-seminomatous germ cell tumor of the testis in clinical stage I were treated only by orchidectomy. The very careful follow-up--with tumor marker assays every 3 weeks, chest X-rays every 6 weeks and CT-scans of the lungs and retroperitoneum every 3 months--revealed metastases in 7 of the patients (21%). All these relapses were diagnosed within 6 months of the orchidectomy. Para-aortic node metastases were found in 5 of the 7 patients, with additional inguinal node metastases in 1 and additional lung metastases in 1; 2 patients had only lung metastases. Six of the 7 patients with a relapse were given chemotherapy (PVB); 1 patient refused chemotherapy. In view of residual disease a surgical excision was performed; it revealed necrosis as well as mature teratoma. All 33 patients are still alive, the post-orchidectomy follow-up period being 12-38 months.

Adolescent↗
PubMed1985

Significance of human chorionic gonadotropin, alpha-fetoprotein, and pregnancy-specific beta-1-glycoprotein in the detection of tumor relapse and partial remission in 126 patients with nonseminomatous testicular germ cell tumors.

After surgery and initial treatment, 126 patients with nonseminomatous germ cell tumors of the testis were followed by estimation of serum human chorionic gonadotropin (HCG), alpha-fetoprotein (AFP), and pregnancy-specific beta-1-glycoprotein (SP-1). The median follow-up time was 39 months (range, 12-69 months). An evaluation was made of the sensitivity, specificity, and predictive value of these markers to detect tumor relapse (TR) and partial remission (PR) rates. Five of the 35 (14%) Stage I patients had a TR, and in 4 the TR was recognized early by increasing serum levels of HCG (four times) and AFP (one time). In Stage II and III disease 17 of the 91 (18%) patients had a TR or PR. In 15 of the 17 patients TR and PR were associated with elevated serum levels of HCG (nine times), AFP (seven times), and SP-1 (five times). Rising levels of HCG and/or AFP preceded a clinical confirmation of TR and PR by 4 to 8 weeks. Serum SP-1 did not add useful information. The combined use of serum HCG and AFP gives a sensitive indicator for TR and PR: 19 of 22 (86%) of such patients were recognized. The specificity (98% and 100%, respectively) and the predictive value of positive tests (87% and 100%, respectively) were high for both HCG and AFP.

Chorionic Gonadotropin↗
PubMed1985

Serum ferritin determinations are of no value in the management of patients with disseminated non-seminomatous germ cell tumors.

In this study the clinical significance of serum ferritin (SF) determinations was evaluated in patients with disseminated non-seminomatous germ cell tumors (NSGCT). The SF levels during the presence of active tumor but before institution of combination chemotherapy (cis-platinum, vinblastine and bleomycin, PVB) were within the normal limits in 38/47 NSGCT patients. During PVB treatment peaking SF levels were observed in relationship to the drug administration, whereas alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) serum levels decreased continuously. Other drugs also caused temporary increases in SF levels. Tumor recurrence was not recognized by SF increases in all eight patients tested. Based on the results we conclude that serial SF determinations are of no value in monitoring patients with NSGCT.

Adult↗
PubMed1985

Serum beta 2-microglobulin: a real improvement in the management of multiple myeloma?

Beta 2-microglobulin (B2-m) determinations in serum have recently been introduced as a method of stratifying patients suffering from multiple myeloma. Conflicting results from several studies prompted us to study retrospectively the correlation of B2-m with presenting features and disease stage, as well as the prognostic value of B2-m, in 87 myeloma patients. Significant correlations were found between B2-m and presenting features such as haemoglobin level, serum calcium level and total body myeloma cell mass. The strongest correlation existed between B2-m and serum creatinine (r = 0.68). B2-m did not discriminate between the different disease stages as defined by Durie and Salmon, nor between myeloma Stage IA and monoclonal gammopathy of undetermined significance (MGUS). Considered alone, B2-m was found to have prognostic value in terms of survival. This correlation disappeared after correction for serum creatinine level and tumour load (multivariate analysis). Furthermore, changes in tumour load during therapy were not reflected in changes in B2-m levels, thereby rendering B2-m levels invalid as tumour marker. Our findings indicate no value for B2-m determinations in the staging and follow-up of myeloma patients.

Creatinine↗