Biomedical subjects
Publications and source records attributed to A Castella.
A case of granulocytic sarcoma of the hard palate in an elderly woman is presented. The diagnosis was suspected on the basis of histologic findings in routine tissue sections and confirmed by cytochemical and electron microscopic studies. No systemic evidence of myeloid leukemia or of any other myeloproliferative disorder was documented in the patient, who died of an unrelated cause shortly after diagnosis.
Platelet-type von Willebrand's disease is a recently described autosomal dominant bleeding disorder characterized by decreased ristocetin cofactor activity, lack of the higher molecular weight von Willebrand Factor (vWF) multimers on SDS agarose gel electrophoresis, increased platelet aggregation with low concentrations of ristocetin, and increased ristocetin-induced binding of normal vWF to patient platelets. In this report the authors describe a 17-month-old male with Platelet-type von Willebrand's disease, inherited from the paternal side of his family, who developed an inhibitor specific to Factor VIII:C. The patient's plasma inhibited normal plasma VIII:C and partially purified VIII:C; it did not appear directed against normal VIIIR:Ag or ristocetin cofactor. This antibody is therefore similar to inhibitors that develop in some transfused hemophilia A patients. Since low VIII:C, VIII:CAg, and VIII:C/VIIIR:Ag ratio were encountered in his mother, it is likely that this patient has inherited hemophilia A in addition to Platelet-type von Willebrand's disease.
The French-American-British (FAB) classification of acute lymphocytic leukaemia (ALL) has recently been modified to improve its reproducibility. We therefore thought it beneficial to test the utility of this modified classification in the prognosis of children with ALL. Eighty-eight patients of less than 18 years of age with ALL were subtyped according to the modified FAB classification by two independent observers. The initial concordance was 86%. Seventy per cent of the patients were subtyped as L1, 27% as L2 and 3% as L3. Patients with L3 subtype were not analysed further. No significant differences were observed between L1 and L2 subtypes when the distribution of other prognostic factors were examined. No differences were observed between L1 and L2 subtypes in the achievement of complete remission. Patients with L1 morphology demonstrated no significant increased duration of first remission or survival when compared to patients with L2 morphology. We conclude that the morphology of lymphoblasts may not be an independent prognostic variable in patients with ALL.
Platelet-type von Willebrand disease (vWD) and pseudo-vWD are two recently described intrinsic platelet defects characterized by enhanced ristocetin-induced agglutination in platelet-rich plasma. A similar finding is also typical of type IIB vWD, where it has been related to a von Willebrand factor (vWF) rather than a platelet abnormality. Platelet aggregation induced by unmodified human vWF in the absence of other stimuli has been reported in pseudo-vWD. In this study we demonstrate that vWF induces aggregation in platelet-type but not type IIB vWD. Aggregation is observed when normal plasma cryoprecipitate or purified vWF are added to platelet-rich plasma. Cryoprecipitate also aggregates washed platelets, although at higher concentrations than required for platelet-rich plasma. Purified vWF, however, induces significant aggregation of washed platelets only when plasma is added. EDTA inhibits vWF-induced aggregation. Its effect can be overcome by calcium but much less effectively by magnesium ions. Unstimulated platelets in platelet-rich plasma from patients with platelet-type but not type IIB vWD bind 125I-vWF in a specific and saturable manner. All different sized multimers of vWF become associated with platelets. Both aggregation and binding exhibit a similar vWF concentration dependence, suggesting that a correlation exists between these two events. Removal of ADP by appropriate consuming systems is without effect upon such binding or upon vWF-induced aggregation. Thrombin-induced 125I-vWF binding to washed platelets is normal in platelet-type as well as type IIB vWD. These results demonstrate that a specific binding site for unmodified human vWF is exposed on unstimulated platelets in platelet-type vWD. The relatively high vWF concentrations required for aggregation and binding may explain the lack of significant in vivo aggregation and thrombocytopenia in these patients. Moreover, these studies provide additional evidence that platelet-type and type IIB vWD are different diseases with distinct pathogeneses.
In four cases, the morphology of neoplastic cells from the peripheral blood and bone marrow suggested the diagnosis of American Burkitt's lymphoma or acute lymphocytic leukemia (French--American--British--Classification; FAB-L3). Cytochemical and immunologic studies, however, indicated that the neoplastic cells in one case were characteristic of acute lymphocytic leukemia (non-B, non-T-cell type); in another case, metastatic carcinoma; and in two two cases acute myelomonocytic leukemia. We conclude that cytochemical and immunologic cell markers are necessary for the diagnosis of American Burkitt's lymphoma. In addition, neoplastic cells simulating lymphoblasts of acute lymphocytic leukemia, FAB-L3 may derive from non-B lymphocytic lineage.
A diagnosis of diffuse poorly differentiated lymphocytic lymphoma was made from a biopsy of a scapular mass on a 24-month-old child. The bone marrow and peripheral blood were not involved in the neoplastic process. Neoplastic cells stained negatively for Sudan black B, myeloperoxidase, periodic acid-Schiff reagent, alpha-naphthyl acetate esterase, and acid phosphatase. In addition, neoplastic cells did not form nonimmune rosettes with sheep erythrocytes or contain surface membrane immunoglobulin. However, neoplastic cells were positive for terminal deoxynucleotidyl transferase and "Ia-like" antigen. We conclude that this non-Hodgkin's lymphoma has a cytochemical and immunologic phenotype similar to that of lymphoblasts from cases of non-T, non-B acute lymphocytic leukemia.
An autosomally transmitted bleeding diathesis sharing some, but not all, features previously described in von Willebrand's disease (vWd) was studied in five patients representing three generations of a single family. Bleeding times in the upper normal range in conjunction with low-normal platelet counts, normal factor VIII coagulant activity and VIII-related antigen, decreased VIII-ristocetin cofactor activity, selective decrease of the higher molecule weight factor VIII/von Willebrand factor (VIII/vWF) multimers, and increased ristocetin-induced platelet agglutination at low ristocetin concentrations were characteristic. Binding of patient VIII/vWF to washed normal platelets was within normal limits, whereas binding of normal VIII/vWF to patient platelets was significantly increased (p less than 0.001 at 0.6 mg/ml ristocetin). This disorder accordingly appears to involve an intrinsic platelet abnormality affecting platelet-VIII/vWF interactions. It is proposed that the concept of vWD be broadened to include patients with this abnormality, which may appropriately be called "Platelet-type von Willebrand's disease."
An autoantibody was found on the red cells of a patient who had never been transfused previously, but was ill with metastatic adenocarcinoma. The patient's blood group was A1. In addition, the patient's serum and the eluate from the patient's red cells agglutinated A1 but not A2, B, and O red cells. This auto-A1 antibody was reactive at a wide thermal range and was inactivated by dithiothreitol, suggesting the presence of an IgM immunoglobulin. Moreover, the antibody was not associated with a hemolytic anemia.
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Aim of the study is to describe the application of surgical site infection (SSI) control procedures in general surgery operating rooms of Piedmont region hospitals. A specific data collection form was designed to record information. 54 questionnaires were compiled. Piedmont legislation related to operating rooms' equipment is obeyed in more than 90% of hospitals. Nevertheless, there are some critical aspects than could be risk factors for SSI or that are not useful in order to prevent them: use of UV radiation (11.3%), use of tacky mats at the entrance of the operating room (5.7%), special cleaning of operating rooms after contaminated or dirty operations (73.6%) and routine environmental sampling (10%) that is strongly recommended by ISPESL guideline in disagreement with international recommendations. Steam autoclave is used for surgical instruments sterilization by 100% of hospitals, but only 50% of them performs an annual validation of both autoclave performance and sterilization procedures. The study gave useful information in order to promote some structural modifications and personnel education for efficacious SSI prevention and control.
The presence of terminal deoxynucleotidyl transferase (TdT) has been determined in neoplastic cells from 50 patients with non-hematologic tumors as well as neoplastic cells from 85 patients with hematologic malignancies. The results indicate that TdT is not present in cells from non-hematologic tumors, Hodgkin's lymphoma, B cell lymphoproliferative disorders, peripheral T cell neoplasms, reactive lymphadenopathy, and acute non-lymphocytic leukemia. In contrast, TdT activity is present in non-T non-B cell acute lymphocytic leukemia, T cell acute lymphocytic leukemia, T cell lymphoblastic lymphoma and chronic granulocytic leukemia in blast crisis. It is concluded that the TdT assay is a measurement useful in the differential diagnosis of some hematologic malignancies.