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H Knecht

Publications and source records attributed to H Knecht.

At least 91 records · Page 5Linked to original sources
PubMed1990

[Hematological parameters and prognosis in established or imminent HELLP syndrome. Apropos of 12 case reports].

We describe the clinical and biological characteristics of 12 pregnant women with the HELLP syndrome as defined by Weinstein in 1982 (H for hemolysis, EL for elevated liver enzymes and LP for low platelet count). The data demonstrate that this syndrome is an obstetric emergency threatening the lives of both mother and child. However, if delivery is prompt the prognosis is good. The suspicion of gestosis requires a hematological assessment (complete blood count and close examination of blood film, evaluation of hemostasis) as an essential component in therapeutic decisions.

Adult↗
PubMed1990

[Isolated prolongation of the PTT: 2-year retrospective study].

The hemorrhagic risk associated with isolated prolongation of the PTT has been evaluated in a 2-year retrospective study. Of the 60 cases thus found, a hemorrhagic risk was present in 15 patients of whom 7 had hemophilia A, 5 von Willebrand's disease and 3 factor XI deficiency. Among the other etiologies not associated with a bleeding tendency, there were 31 proved or suspected cases with inhibitors of the PTT, most of whom were children, 2 factor XII deficiencies, 2 prekallikrein deficiencies and 4 contact phase activations. Isolated prolongation of the PTT is therefore without specificity and needs further investigation of hemostasis to determine the associated hemorrhagic risk.

Factor XI Deficiency↗
PubMed1990

[Prekallikrein deficiency: apropos of 2 cases].

An isolated, considerably prolonged aPTT (117 and 112 sec respectively; normal range 26-36 sec) was discovered during the preoperative workup in 2 patients aged 48 and 66 years. Both had a negative personal and family history for bleeding. Levels of the intrinsic coagulation factors which potentially cause a bleeding risk (VIII, IX, XI) were normal, and an inhibitor of the aPTT could not be detected. Investigation of the contact phase revealed a severe functional deficiency (less than 1%) of prekallikrein (PK) which was diagnostic of the homozygous state. Complete correction of the aPTT after prolonged activation of the contact phase and after addition of 0.2 volume of normal plasma to the sample is suggestive of this diagnosis, which needs to be confirmed by determination of the functional PK. Though deficiency of PK does not carry a bleeding risk, it is important to identify such cases in order to avoid time-consuming investigations in a surgical emergency situation.

Adult↗
PubMed1990

Detection of Epstein-Barr virus DNA by polymerase chain reaction in lymph node biopsies from patients with angioimmunoblastic lymphadenopathy.

Epstein-Barr virus DNA was detected by the polymerase chain reaction (PCR) in five lymph node biopsies from eight patients with diagnosis of angioimmunoblastic lymphadenopathy (AILD). Three pairs of specific primers detected EBV DNA sequences near the 5' end (Bam W region), the middle (BMRF 1 region) and the 3' end (Eco RI D region) of the viral genome with equal accuracy when 1 microgram of DNA and 30 amplification cycles were used. When only 100 ng of DNA were screened with the BMRF 1 set of primers, a specific amplification product was still identifiable. The 593 base pair amplification product obtained using the Eco RI D set of primers was shown to contain an expected Sma I site at position 215, confirming the viral origin of the amplified sequence [corrected]. Our findings indicate that lymph nodes of AILD patients frequently harbour the entire EBV genome at a high percentage of at least 1 viral copy per 15,000 human cells.

Base Sequence↗
PubMed1990

[Immunophenotypic and genotypic characterization of T-cell populations in thymomas].

The T cell component of eight thymomas has been studied by immunohistochemistry and Southern blot analysis. In the cortical areas of thymomas the T cells expressed an immature cortical phenotype. In cortical and medullary areas T cell Receptor (TcR) alpha-beta lymphocytes heavily predominated over TcR gamma-delta lymphocytes. No genomic rearrangement of TcR and Immunoglobulin genes could be detected, thus supporting the non neoplastic nature of the lymphocyte component in thymomas.

Antigens, CD↗
PubMed1990

[Phenotypic and genotypic characterization of splenic infiltrates in hairy cell leukemia].

Cells of splenic infiltrates of five patients with hairy cell leukemia have been analyzed for the expression of immunoglobulin by immunohistochemistry and for rearrangement of T cell receptor and immunoglobulin genes by the Southern blot technique. In each case surface immunoglobulins were found with monoclonal expression of light chains. Concomitantly, heavy and light chain gene rearrangements were present. These results confirm the B cell nature of hairy cells.

Blotting, Southern↗
PubMed1989

[Hairy cell leukemia: study of genomic rearrangements in splenic infiltration].

Genomic DNA extracted from heavily infiltrated spleens of 5 patients with hairy cell leukaemia was hybridized with genomic probes for immunoglobulin genes. The rearrangement pattern, correlating well with the immunohistochemical findings, was that of a clonal B-cell proliferation in all cases. Analysis of the lambda light chain genome with two different probes enabled more accurate localization of the clonal rearrangements within this genome. A small additional T-cell population identified in 3 cases was immunogenotypic of polyclonal (reactive) nature.

DNA Probes↗
PubMed1989

Polyclonal rearrangements of the T-cell receptor beta-chain in fatal angioimmunoblastic lymphadenopathy.

Genomic rearrangement of germline T-cell antigen receptor (TcR) and immunoglobulin (Ig) genes was studied by Southern blot analysis in seven patients with angioimmunoblastic lymphadenopathy (AILD). In three cases clinically suspected of transformation into malignant lymphoma, hybridization with the TcR beta probe showed markedly dimished intensity in the 11.5 kb germline band after Eco RI digestion and normal germline configuration after Hind III and Bam HI digestion, indicating polyclonal T cell rearrangements. A clonal rearrangement of the TcR beta gene was detected in only one case at initial biopsy. No monoclonal rearrangement of Ig genes was observed. These data show that in some cases of AILD disease progression is indicated by polyclonal TcR rearrangements and not by outgrowth of a malignant clone, supporting the concept of AILD as an immunoregulatory disorder.

Blotting, Southern↗
PubMed1988

Functional hyposplenia after allogeneic bone marrow transplantation is detected by epinephrine stimulation test and splenic ultrasonography.

Splenic function was evaluated after subcutaneous epinephrine injection (0.5 mg/m2) in 15 bone marrow transplant (BMT) recipients, 10 healthy volunteers and 5 healthy asplenic men. Healthy volunteers and BMT recipients with minor primary induction chemotherapy (mRx) showed similar rise in platelet (plt) and neutrophil granulocyte (PMN) counts and similar contraction of spleen. Patients with intensive primary induction chemotherapy (MRx), however, had significantly smaller spleens and spleen contraction (p less than 0.02) and no plt increase (p less than 0.05) when compared with healthy volunteers. 2 patients with MRx even exhibited a decrement of plt count after epinephrine, similar to that observed in all 5 healthy asplenic subjects tested. Our results suggest that mRx and conditioning for BMT including total body irradiation (TBI) does not alter the splenic function, but that the combination of MRx and conditioning regimen including TBI may cause functional hyposplenism, sensitively revealed by reduction in plt count after epinephrine stimulation.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1987

[Provisional treatment results of intensive combination chemotherapy (m-BACOD) in non-Hodgkin lymphoma of intermediate and high malignancy].

10 patients with diffuse large cell lymphoma were treated with 10 cycles of m-BACOD. 7 patients presented with a pathological stage IV, 2 with a clinical stage III and one with a clinical stage II disease. 8 patients have been in complete remission for 3-21 months (mean 9 months) after completion of therapy. One patient with T-immunoblastic lymphoma and bulky mass died of progressive disease after 6 cycles of m-BACOD. A second patient with T-immunoblastic lymphoma relapsed 24 months after completion of therapy. Treatment-related major complications, especially MTX-related ulcerative stomatitis, did not occur.

Adult↗
PubMed1987

Diagnostic and prognostic value of monoclonal antibodies in immunophenotyping of angioimmunoblastic lymphadenopathy/lymphogranulomatosis X.

Immunophenotyping of frozen lymph node sections from seven patients with morphologically defined angioimmunoblastic lymphadenopathy (AILD) was performed with a panel of 20 monoclonal antibodies (MoAb). MoAb for identification of dendritic reticulum cells showed remnants of follicular structures in all cases. In four cases these 'burnt out' follicular structures were associated with clusters of polyclonal B-cells. Vascular proliferation and small amounts of intercellular collagenous fibrils were reliably revealed by MoAb CIV22 against basement membrane collagen. Cellular infiltrates of T4+ cells prevailed in four cases, of T8+ cells in one case. In one case conventionally identified blasts were of T- and B-cell origin. Expression of cell proliferation associated nuclear antigen identified by MoAb Ki-67 was present in more than 25% of lymph node cells in three patients with fatal outcome, but in less than 10% of cells in two patients with a better clinical course. Therefore MoAb Ki-67 may represent a valuable prognostic marker in AILD.

Adolescent↗
PubMed1987

Diagnostic and prognostic value of monoclonal antibodies in immunophenotyping of T cell lymphomas.

6 cases of post-thymic T cell lymphoma (PTCL) and 4 cases of T lymphoblastic lymphoma were investigated with a panel of 21 monoclonal antibodies (MoAb). The PTCL group was composed of 2 by 2 cases of lymphoepithelioid cell lymphoma, T zone lymphoma and T immunoblastic lymphoma. In lymphoepithelioid cell lymphoma, the cell proliferating activity was low, and a malignant clone was not identifiable by the methods used. In the cases of T zone lymphoma and T immunoblastic lymphoma, malignant populations were detectable on the grounds of immunologic marker profile combined with cytologic particularities. The 4 cases of T lymphoblastic lymphoma were of a common cortical thymic phenotype (T4+, T8+, T6+) and presented with a mediastinal mass. In 3 of them, cell proliferation marker (Ki-67) was expressed by most tumor cells. Cell proliferating activity, however, did not inversely correlate with survival.

Adolescent↗
PubMed1986

Toxoplasmosis in hairy-cell leukaemia.

Toxoplasma serology was performed in 28 patients with hairy-cell leukaemia and was positive in eight patients (29%). In two patients (7%) reactivated toxoplasmosis was proven by either isolation of Toxoplasma gondii or by significant antibody titre rise with generation of specific IgM-antibodies. In four patients (14%), a clinical diagnosis of active toxoplasmosis was based on signs and symptoms, serologic tests, and response to specific treatment. The high proportion of patients in which active toxoplasmosis was proven or probable (six; 21%) may be related to the presence of severe monocytopenia. In patients with hairy-cell leukaemia developing fever of unknown origin and myositis, toxoplasma serology should be performed, particularly because treatment of active toxoplasmosis usually is successful.

Adult↗
PubMed1985

Central nervous system involvement in hairy cell leukemia.

A patient with central nervous system involvement by hairy cell leukemia is reported. Hairy cells were identified in the cerebrospinal fluid by electron microscopy and by tartrate-resistant acid phosphatase positive staining. Intrathecal treatment with methotrexate resulted in neurologic improvement, but was complicated by Cryptococcus neoformans meningitis. The leukemic phase of the disease was later successfully controlled by treatment with alpha interferon. Surface marker studies indicated a B- and T-cell phenotype of the hairy cells.

Brain Neoplasms↗
PubMed1985

Histological, immunohistological and autopsy findings in lymphogranulomatosis X (including angio-immunoblastic lymphadenopathy).

172 cases of lymphogranulomatosis X (LgX) were studied by light microscopy. In 53 cases immunohistological techniques for detecting intracytoplasmic immunoglobulins were applied. In the lymph nodes of all cases the nodal architecture was found to be effaced. Active germinal centres were absent, and there was a generalized, markedly increased proliferation of epithelioid venules. A polymorphic infiltrate was present in all cases. It was dominated by immunoblasts in 14%, by plasma cells in 16%, by epithelioid cells in 23% and by lymphocytes in 6% of the cases. In the remaining 41% of the cases no special type of cell predominated (mixed cell type of LgX). The clusters of clear cells present in some cases with immunoblastic predominance did not stain for intracytoplasmic immunoglobulins; in contrast, the basophilic immunoblasts exhibited a polyclonal Ig pattern. In some of the cases with lymphocytic predominance most of the lymphocytes showed abundant cytoplasm with azurophil granules. Transformation into malignant lymphoma was proven at autopsy in 5 of 38 cases (13.2%). Malignant transformation (biopsy and autopsy material) was confirmed in a total of 11 of 172 cases (6.4%) and suspected in an additional 7%. Among the malignant lymphomas were one immunologically proven B-immunoblastic lymphoma, one peripheral T cell lymphoma and 5 cases of Hodgkin's disease. An association between LgX and carcinoma was histologically verified in 7 cases. 26 cases with active germinal centres and 11 cases with only locally pronounced vascularization but with histological and cytological changes that were otherwise similar to LgX were designated as hyperimmune reactions (HR). These cases had a significantly better prognosis. Two cases that presented as HR with active germinal centres later developed into LgX. It is suggested that the disappearance of active germinal centres is important in the pathogenesis of LgX. The possibility that this may correspond morphologically to an alteration of different components of the T-cell system is discussed.

Bone Marrow↗
PubMed1985

Megakaryocytopoiesis in different forms of thrombocytosis and thrombocytopenia: identification of megakaryocyte precursors by immunostaining of intracytoplasmic factor-VIII-related antigen.

Megakaryocytopoiesis was investigated with a polyclonal (26 cases) and a monoclonal (20 cases) antibody to factor-VIII-related antigen (factor VIII RAg) with the indirect peroxidase-antiperoxidase (PAP) method on air-dried bone marrow aspirates (BM). Numerous megakaryocyte precursors were identified in 5 patients with essential thrombocythemia (ET) and the 2 patients with acute myelogeneous leukaemia (AML) after recovery from therapeutic aplasia. Small megakaryocyte precursors were rare in controls (C), patients with reactive thrombocytosis (RT) and immune thrombocytopenia (IT). In 2 patients with severe alcoholism the number of mature megakaryocytes increased after 5 and 7 days of abstinence, respectively.

Antibodies, Monoclonal↗