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J D Hoyer

Publications and source records attributed to J D Hoyer.

31 records · Page 2Linked to original sources
PubMed1998

Hb Tak confirmed by DNA analysis: not expressed as thalassemia in a Hb Tak/Hb E compound heterozygote.

Hemoglobin variants in which a frameshift results in chain elongation are unusual and also have a low population frequency. Hb Tak was previously characterized by amino acid analysis, and it was assumed to be due to an insertion of the dinucleotide CA into codon 146 [CAC-->CA(CA)C] which abolishes the normal stop codon at position 147. This insertion causes a frameshift which results in elongation of the beta chain by 11 amino acids. This variant has previously been described in a few Thai families. We report the DNA sequence of Hb Tak in an individual of Cambodian descent who is a Hb E/Hb Tak compound heterozygote. In contrast with extended variants of the alpha-globin chain that are expressed as alpha-thalassemias, the hematologic effect of Hb Tak/Hb E is a mild polycythemia. The combination of Hb Tak/Hb E is not expressed as a thalassemia.

Adult↗
PubMed1998

Hemoglobin Old Dominion/Burton-upon-Trent, beta 143 (H21) His-->Tyr, codon 143 CAC-->TAC--a variant with altered oxygen affinity that compromises measurement of glycated hemoglobin in diabetes mellitus: structure, function, and DNA sequence.

OBJECTIVE: To determine the nature and characteristics of a unique hemoglobin variant that causes a spurious increase in glycated hemoglobin (HbA1c). MATERIAL AND METHODS: Blood specimens from four unrelated persons with this hemoglobin variant were examined by conventional laboratory methods, including electrophoresis, high-performance ion-exchange chromatography, and isoelectric focusing; by amino acid sequence analysis, polymerase chain reaction-based DNA sequence analysis, and electrospray ionization mass spectrometry, to establish the molecular structure; and by studies of oxygen affinity under varied conditions, to define the functional characteristics of the hemoglobin variant. RESULTS: The unique hemoglobin variant observed in these four cases is due to the mutation CAC-->TAC, at beta-globin gene codon 143, corresponding to beta 143 (H21) His-->Tyr. This amino acid substitution affects an important 2,3-diphosphoglycerate binding site and slightly increases the oxygen affinity of the hemoglobin variant. CONCLUSION: A hitherto unrecognized hemoglobin variant, encountered in four unrelated persons of Irish or Scots-Irish ancestry, hemoglobin Old Dominion/Burton-upon-Trent, beta 143 (H21) His-->Tyr, has now been characterized at the molecular, structural, and functional levels. Although it is associated with a slight increase in oxygen affinity, it is without hematologic effect, and its only clinical significance is that it coelutes with HbA1c on ion-exchange chromatography and thereby causes a spurious increase in HbA1c and compromises the use of this analyte to monitor the treatment of diabetes mellitus.

Adult↗
PubMed1997

Immunohistochemical demonstration of acid phosphatase isoenzyme 5 (tartrate-resistant) in paraffin sections of hairy cell leukemia and other hematologic disorders.

The demonstration of tartrate-resistant acid phosphatase (TRAP) activity has long been a cornerstone in the diagnosis of hairy cell leukemia (HCL). Recently a monoclonal antibody to this enzyme has been developed that can be used in an immunoperoxidase method on paraffin-embedded tissues. By using a peroxidase-labeled streptavidin biotin method, paraffin sections of B5 and formalin-fixed tissue from 86 cases of HCL (41 bone marrow, 36 spleen, 9 liver) were stained with the antibody to TRAP and compared against staining for CD20 (L26) and DBA.44 (DAKO, Carpinteria, Calif). In addition, 193 specimens (127 bone marrow, 42 lymph node, 19 spleen, 5 other) from a variety of neoplastic and nonneoplastic hematologic conditions were stained using the monoclonal antibody to TRAP. For comparison, these cases were also stained with DBA.44. In the cases of HCL, 80 of 86 specimens were immunoreactive for TRAP. While the antibody to TRAP generally stained less than 50% of the hairy cells, CD20 and DBA.44 stained 90% and 50% to 60% of hairy cells, respectively. Two of three cases of marginal zone lymphoma showed weak immunoreactivity to the TRAP antibody. Two specimens from a patient with Gaucher's disease and 8 of 13 cases of mastocytosis also showed positivity to the TRAP antibody in the macrophages and mast cells, respectively. In contrast, staining for DBA.44 was positive in 3 of 9 cases of B-cell large cell lymphoma, 1 of 4 cases of mantle cell lymphoma, and in the paraimmunoblasts of 1 of 7 cases of small lymphocytic lymphoma. Only HCL was TRAP and DBA.44 positive. This antibody to TRAP is a useful addition to the diagnosis of HCL but should be used in conjunction with CD20 and DBA.44. The use of this antibody to determine minimal residual disease after chemotherapy was not addressed.

Acid Phosphatase↗
PubMed1997

Primary laryngeal lymphoma.

Primary laryngeal lymphoma is a very rare entity, with fewer than 50 cases reported in the English literature in the past 60 years. Close scrutiny of some of these case reports reveals that the larynx was not always the only site of involvement, thereby diminishing the total number of patients with primary laryngeal lymphoma to fewer than 35. The authors report a series of six patients, who were seen and evaluated at the Mayo Clinic between 1952 and 1995, with stage IAE non-Hodgkin's lymphoma of the larynx. Three patients had large-cell lymphomas according to the REAL (Revised European-American Lymphoid) classification. The other three had a small lymphocytic lymphoma, follicular small cleaved lymphoma, and follicular mixed lymphoma. All patients received radiation therapy alone as initial therapy for their disease and all patients had a complete remission to initial therapy. Four patients subsequently relapsed and the histology at relapse was the same as the initial histology in all four patients. Five patients have died, three of lymphoma, with a median survival of 67 months (range, 40 to 228 months). In view of the heterogeneity of histologies in this group of lymphomas, the variability in duration of response, and the significant number of patients who died of their disease, it is more likely that primary laryngeal lymphoma is an unusual presentation of non-Hodgkin's lymphoma than a separate disease entity. Despite the small number of patients in this study, the data would suggest that patients are best treated according to the histology of the lymphoma, rather than the limited stage and location of the disease.

Adult↗
PubMed1997

Hb T-Cambodia, a beta chain variant with the mutations of Hb E and Hb D-Punjab, confirmed by DNA analysis.

Hemoglobin variants with two amino acid substitutions affecting one globin chain are relatively rare. Hb T-Cambodia, a doubly substituted beta-globin variant, was characterized previously by amino acid sequencing as having sequence alterations in beta 26 (beta 8)Glu-->Lys and beta 121(GH4) Glu-->Gln (1). It is a variant that migrates cathodic to Hb A2 on alkaline electrophoresis and with Hb A on acid citrate agar electrophoresis. We report here the mutations of Hb T-Cambodia at the nucleotide level using DNA sequencing, in beta-globin gene codon 121 (GAA-->CAA) and in codon 26 (GAG-->AAG). These are the mutations of Hb D-Punjab and Hb E, respectively.

Adult↗
PubMed1996

Hemoglobin S/hemoglobin Osler: a case with 3 beta globin chains. DNA sequence (AAT) proves that Hb Osler is beta 145 Tyr-->Asn.

A 13-year-old African-American female with erythrocytosis and three different beta globins on electrophoresis beta A, beta S, and beta Osler, raised the possibility that one chromosome 11 might contain a duplicated beta globin gene, since there are normally only 2 beta globin genes. DNA sequence analysis showed GTG at codon 6 in exon 1, corresponding to Hb S and AAT at codon 145 in exon 3, indicating a substitution of Asn for Tyr. Thus, Hb Osler undergoes spontaneous post-translational deamidation, beta 145 Asn-->beta 145 Asp. Unmodified Hb Osler (Asn) co-migrates with Hb A on electrophoresis and co-elutes with Hb A on HPLC; therefore it has not been identified previously. All previous studies have incorrectly identified the mutation as being beta 145 (HC 2) Tyr-->Asp.

Adolescent↗
PubMed1996

Measurement of blood volume and red cell mass: re-examination of 51Cr and 125I methods.

Comparison of results of red cell mass (RCM) measurement by 51Cr and 125I methods in 119 patients showed virtual equivalence. Both methods have an acceptable coefficient of variation (CV) that is < 5%. The 125I method is simpler and much less expensive. Unrealistically narrow "normal ranges" for RCM are likely to lead to misdiagnosis of polycythemia vera. Upper normal limits of 39 mL/kg (males) and 32 mL/kg (females) are consistent with originally published data in normal persons; use of these limits as criteria would reduce the risk of misdiagnosis. No cases of "stress erythrocytosis" or Gaisbock Syndrome were encountered among the 119 cases reviewed.

Blood Volume↗
PubMed1996

Detection and classification of acute leukemia by the Coulter STKS Hematology Analyzer.

This study evaluated the ability of the Coulter STKS Hematology Analyzer (Coulter, Hialeah, FL) to detect and classify acute leukemias involving the peripheral blood. One hundred ten acute leukemias cases with circulating blasts were studied: 72 acute myeloid leukemias were divided into "high WBC count (> 11.0 x 10(9)/L)" (28 AML, 22 ALL) and "normal/low WBC count (< or = 11.0 x 10(9)/L)" (44 AML, 16 (ALL) categories. Most cases in the high WBC count group elicited the blast suspect flag. The remaining cases of AML and ALL in both the high WBC and normal/low WBC count group were detected by the blast flag, other suspect flags, and/or definitive flags. Only one case of AML-M6 was initially missed using these flag combinations; a subsequent analysis elicited the blast flag. The blast populations in the high WBC count group were localized into characteristic myeloblast or lymphoblast regions of the scatterplot in 82.1% of AML and 63.6% of ALL cases, respectively. However, the remaining cases had indeterminate or aberrant scatterplot patterns, such that an accurate leukemia classification was not possible. The scatterplot pattern also was not helpful in differentiating AML FAB subclasses. The authors conclude that using a combination of appropriate suspect and definitive flags to trigger checking criteria and microscopic review, the Coulter STKS Hematology Analyzer will be successful in detecting virtually all cases of acute leukemia involving the peripheral blood. Although the scatterplots may give useful information, the patterns obtained are not sufficiently distinctive to aid in classifying acute leukemias.

Acute Disease↗
PubMed1996

Hb Cook [beta 132(H10)Lys-->Thr]: a new hemoglobin variant in a southeast Asian family.

Approximately 700 hemoglobin variants have been reported, causing a variety of clinical manifestations, with the majority being clinically silent. We report a new hemoglobin variant, Hb Cook, that was found in combination with Hb E in a child of Thai origin. DNA sequencing of the beta-globin gene showed that the mutation is AAA-->ACA in codon 132, corresponding to beta 132 (H10)Lys-->Thr.

Asia, Southeastern↗
PubMed1995

True T-cell chronic lymphocytic leukemia: a morphologic and immunophenotypic study of 25 cases.

We studied 25 T-cell chronic lymphocytic leukemia (T-CLL) cases collected over a 15-year period. Immunophenotypic analysis was performed in each case; 12 cases were evaluated by cytogenetics, and gene rearrangement studies were performed in 14 cases. The median age was 57 years with a male predominance (M:F, 15:10). The median presenting lymphocyte count was 36.3 x 10(9)/L (range, 3.9 to 438 x 10(9)/L). Fourteen patients (56%) had shotty adenopathy and ten (40%) had mild-to-moderate splenomegaly at presentation; four (16%) had erythematous skin lesions. The lymphocytes were predominantly small; some cases had a minor component of medium-sized cells (< 10%). The nuclear: cytoplasmic ratios were uniformly high with round to oval nuclei; however, a wide spectrum of nuclear outlines could be found, ranging from minimally to markedly convoluted. Nucleoli were either absent or small and inconspicuous. These lymphocytes did not have the morphology of prolymphocytes and did not contain cytoplasmic granules. Bone marrow infiltration was generally in an interstitial pattern; the degree of involvement ranged from 15% to 90%. Immunophenotyping showed that the lymphocytes were mature T-cells with a predominant CD4+ immunophenotype. Three cases displayed a CD8+ immunophenotype. The patients were treated with a variety of chemotherapeutic regimens with only a minimal response observed in two of 20 patients. We conclude that T-CLL is an uncommon chronic lymphoproliferative disorder (CLPD) that can be morphologically similar to B-CLL, is distinct from T-prolymphocytic leukemia, and has an aggressive clinical course that is refractory to therapy. It may also be difficult to distinguish T-CLL from other T-CLPD, especially the leukemic phase of peripheral T-cell lymphoma and some cases of Sézary syndrome.

Adult↗
PubMed1995

Primary renal non-Hodgkin's lymphoma. An unusual extranodal site.

BACKGROUND: Primary renal non-Hodgkin's lymphoma (NHL) is rare. Because the renal parenchyma does not have lymphatics, the existence of this entity has been questioned. The goal of this study was to determine the clinical presentation, pathologic features, and disease course of patients with primary renal NHL and review the pertinent literature on this unusual extranodal NHL. METHODS: All medical records from the Mayo Clinic from 1976 to 1992 with the diagnosis of renal NHL were retrospectively reviewed. One-hundred seventy-six cases were identified, five of which met the criteria for primary renal NHL. The clinical, pathologic, and radiographic features were reviewed in detail and are the basis of this report. RESULTS: The median age at diagnosis of the five patients with primary renal NHL was 60 years (range, 52-63 years) with a male-to-female ratio of 2:3. All patients had flank pain as their initial presentation. Urinalysis was abnormal in only one patient. In three patients, the serum creatinine was elevated. Tumor histology was diffuse large cell in four cases; and small noncleaved non-Burkitt's in one. All five were B-cell immunophenotype. All patients received combination chemotherapy. Although the median survival for the group was only eight months, two remain in complete remission longer than 80 months from therapy. These two had total removal of macroscopic lymphoma and received combination chemotherapy and consolidation radiotherapy. CONCLUSIONS: Primary renal non-Hodgkin's lymphoma does exist. Patients whose lymphomas were completely resected macroscopically and who received combination chemotherapy with consolidation radiation therapy had long disease free survival. Patients with bilateral renal involvement or no debulking of the renal lymphoma tended to have poorer survival.

Antineoplastic Combined Chemotherapy Protocols↗