Are Tidal Salt Marshes Exposed to Nutrient Pollution more Vulnerable to Sea Level Rise?

Over the past four decades, Long Island, NY, USA, has lost coastal wetlands at a rate of 4% per decade due to submergence. In this study, we examined relationships between the rate of tidal salt marsh loss and environmental factors, including marsh elevation, tidal range, and wastewater exposure through analysis of stable isotope ratios of marsh soils and biota. Our goal was to identify factors that increase vulnerability of marshes to sea level rise, with a specific emphasis on the potential role of poor water quality in hastening marsh loss. Our results suggest that wastewater exposure may accelerate loss of intertidal marsh, but does not negatively impact high tidal marsh resilience to sea level rise. And while marsh elevation and tidal range were statistically significant predictors of marsh loss, they similarly displayed opposite relationships among marsh zones. This study suggests that different functional zones of coastal salt marshes may not respond similarly to global change factors, and that elevation may be an important factor mediating eutrophication effects to coastal salt marshes.

Molecular pathology in the diagnosis and treatment of non-Hodgkin's lymphomas.

The non-Hodgkin's lymphomas encompass a wide spectrum of hematologic neoplasms that exhibit different clinical and biological features. Lymphomas classically have been initially assessed based on their cytologic and histologic features. Morphology alone is often inadequate as similar appearing neoplasms may be immunophenotypically and molecularly heterogeneous. Molecular diagnostic methods can provide an additional level of testing that not only helps refine diagnoses but can provide prognostic information. New methods are being refined that may provide information to establish precise diagnostic profiles, provide targets for therapy and provide more sensitive methods for monitoring the success of treatment. Molecular methods will be increasingly utilized and eventually required as the accepted method of diagnosis and for monitoring the disease. Understanding of the molecular abnormality and the pathogenesis of the neoplasm hopefully will lead to therapeutic intervention aimed at the specific molecular defect or its product. The molecular pathology of the non-Hodgkin's lymphomas is discussed.

Kimura's disease: a case report.

Kimura's disease is a rare, idiopathic condition that usually affects young men of Asian descent. The decrease is characterized by swelling and lesions in the head and neck region, with involvement of the subcutaneous soft tissue, major salivary glands, and lymph nodes. Patients almost always have eosinophilia and elevated serum immunoglobulin E levels. The diagnosis is established by biopsy. Kimura's disease is usually self-limiting. Its etiology is unknown but is thought to be a manifestation of an aberrant allergic response. In this paper, we describe the case of a 30-year-old patient who was diagnosed with Kimura's disease at our institution.

Morphology and classification of acute myeloid leukemias.

The morphology and classification of AML are discussed. In addition to routine morphology and cytochemistry, however, it is now necessary to use newer modalities of immunocytochemistry or flow cytometry to confirm a diagnosis. These latter are essential for the diagnosis of the newer described entities of AML with minimal differentiation (FAB-M0) and acute megakaryoblastic leukemia (FAB-M7). Cytogenetics and fluorescent-in-situ-hybridization techniques are also very important for diagnosis as in FAB-M3 (promyelocytic leukemia) but also for detecting those myeloid leukemias that are associated with a favorable or unfavorable response.

Detection of hepatitis C virus RNA sequences in B-cell non-Hodgkin lymphoma.

Serologic testing shows that hepatitis C virus (HCV) may have a role in the pathogenesis of B-cell non-Hodgkin lymphomas (B-cell NHLs). We tried to demonstrate HCV RNA sequences in paraffin-embedded tissue from B-cell NHLs by reverse-transcription double polymerase chain reaction (RT-PCR) and Southern blotting. We studied 31 consecutive cases of B-cell NHLs; lymph nodes from 32 patients with diseases other than B-cell NHL were negative controls. Positive-strand HCV RNA was tested with primers for the 5' untranslated region. Replicative negative strand HCV RNA was tested with strand-specific RT-PCR for the 5' untranslated region. Immunohistochemical staining for HCV was done using an antibody to HCV core protein. Positive-strand HCV RNA was detected in 8 patients with B-cell NHL; negative-strand HCV RNA was detected in 6 of these cases, indicating viral replication. All control cases were negative for HCV RNA. Immunohistochemistry showed no staining of lymphoma cells for HCV core proteins in any case. HCV and B-cell NHLs may be associated. RT-PCR on paraffin-embedded lymphoma tissue is an alternative method of testing for HCV. The value of immunohistochemistry could not be ascertained. The exact role of HCV in the pathogenesis of B-cell NHL needs to be studied further.

der(1)t(1;19)(p12;p11): a new nonrandom chromosomal abnormality in myelodysplastic syndrome.

The der(1)t(1;19)(p12;p11) has not been previously reported in myelodysplastic syndrome (MDS). Fluorescence in situ hybridization (FISH) using chromosome 1- and chromosome 19-specific probes, performed on the bone marrow (BM) cells of this patient confirmed the initial karyotype, i.e., 47,XY,+der(1)t(1;19)(p12;p11).

Refractory T cell acute lymphoblastic leukemia with unusual karyotype and interesting immunophenotype.

Karyotype, immunophenotype, and molecular studies are important in the evaluation of Acute Lymphocytic Leukemia as these data provide diagnostic as well as prognostic information. We present a case of acute lymphoblastic leukemia with unusual cytogenetics, 45,XY,i(7q),der(9)t(3;9)(q12;p22),del(12)(p12), :der(18)t(3;18)(p14;q22),-3. This karyotype is hypodiploid, showing loss of chromosome 3, a very rare occurrence. Hypodiploidy and translocations are suggestive of a poor clinical outcome. Cytogenetics also showed a chromosome 12p deletion which has been implicated in the oncogenesis of some acute leukemias. Immunophenotype by flow cytometry was positive for CD7 and CD10, T, and precursor B cell markers respectively. Given the specificity of CD7 for T cell processes, it was felt that the flow cytometry was more suggestive of a T cell process. Gene rearrangement studies showing a T cell receptor rearrangement helped confirm the T cell lineage of this malignancy. Hypodiploidy and T cell phenotype are indicators of poor prognosis. Interestingly this patient was refractory to two conventional chemotherapeutic protocols and finally responded to an unconventional protocol of high dose Ara C, etopside, and L asparaginase.

The Tulane University Medical Center/Columbia partnership: opportunities and challenges for pathology.

A joint venture between the largest health-care corporation in the country (Columbia/HCA) and Tulane University Hospital/Clinic was established about 1 year ago. Early indications are that the partnership is successful and mutually beneficial. For Tulane University Medical Center, the joint venture provides financial stability and support for academic centers of excellence. Tulane University Hospital/Clinic will become the referral center for complicated cases from the regional Columbia hospitals. The Tulane University Hospital laboratories are positioned to become the regional referral laboratory for esoteric testing. For the pathologists of the regional Columbia hospitals, the opportunity beckons to form a group of equal partners that will contract with Columbia to provide laboratory services at Columbia hospitals and to consolidate the laboratories in the New Orleans division. Columbia has brought corporate expertise, capital, and opportunities for cost-saving economies of scale to the partnership. Quality and cost-effectiveness of patients care will be emphasized as will research on clinical outcomes. This model of corporate/academic partnership represents a new option for academic medical centers around the country as they respond to the rapid changes in the health-care environment.

Clinical use of B- and T-cell gene rearrangement analysis in hematopoietic disorders.

The clinical application of B- and T-cell gene rearrangement analysis is discussed relative to diagnostic problems in specific lymphoproliferative disorders. This article reviews the use of the Southern blot hybridization technique for B- and T-cell gene rearrangement detection in the analysis of various hematopoietic lesions. Several case studies are presented and analyzed.

The automated white blood cell differential. A current perspective.

The white blood cell differential count represents a major portion of the workload in the hematology laboratory. The traditional procedure whereby a technologist examines a Romanowsky-stained blood film and classifies 100 cells is both labor intensive and imprecise. To significantly improve the precision, the technologist would have to count and classify at least 1000 cells, which is obviously impractical in terms of time and efficiency. Until the availability of the automated hematology instruments, it was not possible to obtain a differential count that could be regarded as statistically significant. Automation is therefore necessary and desirable for both economic and clinical reasons. Automation can also provide a number of instrument-derived parameters tha have attained diagnostic significance in their own right. Analytic and technologic advances have occurred with every generation of hematology instruments. As the means of analysis becomes more sophisticated, additional categories of cells may be expected to be classified, and current categories may be more accurately and precisely defined. It is hoped this will lead to even greater clinical utility, as well as provide quality assurance and assessment methods that need to be developed similar to other procedures in the clinical laboratory.

Basaloid squamous cell carcinoma of the head and neck: a clinicopathologic and flow cytometric study of 10 new cases with review of the English literature.

INTRODUCTION: We describe the clinicopathologic and flow cytometric features of 10 cases of basaloid squamous cell carcinoma (BSCC) of the head and neck to determine if DNA ploidy is a useful prognostic indicator. We also provide a review of 80 cases previously reported in the English language literature. MATERIALS AND METHODS: The 10 cases were obtained from the surgical pathology files of Presbyterian University Hospital and The Eye and Ear Institute, Pittsburgh, PA (1987-1991). In all 10 cases, the microscopic slides and clinical data were reviewed. Flow cytometry was performed using the Hedley technique and formalin-fixed, paraffin-embedded tissue. RESULTS: The mean age of patients with BSCC was 64 years (range, 49 to 75 years). Tumor involved the base of tongue (n = 5), hypopharynx-epiglottis (n = 3), and tonsil (n = 1). One case presented with cervical lymph node metastasis from an unknown primary site. Histologically, BSCC showed a biphasic pattern with basaloid-squamous elements, comedonecrosis, stromal hyalinization, surface dysplasia, and an in situ and/or invasive squamous cell carcinoma component. Flow cytometry revealed six diploid and four aneuploid tumors. Five of six patients with diploid and all four patients with aneuploid tumors developed early regional and/or distant metastases. Of the two patients who died of disease, one had a diploid and the other an aneuploid tumor. CONCLUSION: Our study reaffirms the predilection of BSCC for the base of tongue, pyriform sinus, and supraglottic larynx, and its aggressive biologic behavior with a high incidence of cervical lymph node metastasis (64%), distant spread (44%), and death from disease (38% mortality at 17 months median follow-up). However, in contrast to previous reports, tumor ploidy by flow cytometry provided no additional prognostic information beyond that supplied by routine histologic evaluation.

A new procedure for cell lineage determination in acute leukemias. Myeloperoxidase mRNA detection.

Determination of cell lineage in acute leukemias is essential for diagnosis and treatment. Detection of myeloperoxidase (MPO) mRNA establishes myeloid lineage of leukemic blasts that may be too primitive to be identified as myeloblasts based on morphology, cytochemistry, or immunophenotype. A highly specific and sensitive new procedure for MPO mRNA detection has been developed using HL-60 cells. It involves a microprocedure for total cellular RNA extraction, reverse transcription, and specific amplification of target sequences in the resulting MPO cDNA, by the polymerase chain reaction. Specific primers are designed to amplify an 89-base pair (bp) sequence from the signal peptide, 179 and 318-bp sequences from the start and end, respectively, of the heavy-chain sequence, and a 255-bp sequence overlapping the proregion and light chain. The correct-size amplification products, detected electrophoretically, demonstrate MPO mRNA expression in the leukemic cells analyzed. The sensitivity of this new procedure was evaluated on serial concentrations of HL-60 cells and was found to be 10-10(4) cells depending on the MPO cDNA amplified sequence. No amplification products were obtained using peripheral blood lymphocytes as a negative cellular control. The specificity of the procedure is demonstrated by Southern blotting and hybridization with 32P-labeled oligonucleotide probes specific for each of the amplified sequences. An additional advantage of this procedure is availability of results in 8-24 h, compared with 1-2 weeks for conventional RNA methods.

DNA content in fresh versus paraffin-embedded tissue. Flow cytometric analysis of 100 tumors.

DNA ploidy analysis was determined on 100 consecutive tumors from a wide variety of sites using both fresh and paraffin-embedded tissue on the same specimen. The correlation coefficient (r) value between the methods was 0.85. Aneuploidy was detected by both methods in 51/100 (51%) of the cases. Fresh tissue analysis yielded 10 additional cases (overall 61% aneuploidy) not detected on corresponding paraffin-embedded sections, whereas paraffin-embedded analysis detected 4 additional cases (overall 55% aneuploidy) not revealed by fresh tissue analysis. Fresh tissue analysis produced lower coefficients of variation and resulted in a cleaner preparation with less cellular debris. Fresh tissue analysis was also superior to paraffin for the detection of hypodiploid, near-diploid and multiple peaks. Analysis of paraffin-embedded material allows examination of archival tissue and provides a more rapid means of long-term follow-up and statistical correlations for prognostic studies. Although the overall correlation of both methodologies for DNA analysis showed a minimal variation in results, in our experience fresh tissue analysis has an advantage and is preferable, when available, for ploidy analysis.

Morphological diagnosis of parvovirus B19 infection. A cytopathic effect easily recognized in air-dried, formalin-fixed bone marrow smears stained with hematoxylin-eosin or Wright-Giemsa.

Readily identifiable intranuclear inclusions characterize parvovirus B19 cytopathic effect in formalin-fixed, paraffin-embedded material. Such inclusions are not apparent in air-dried smears of bone marrow aspirates. Brief formalin fixation of bone marrow smears, followed by either hematoxylin-eosin or Wright-Giemsa staining, permitted easy detection of parvovirus B19 inclusions in material from a renal transplant recipient with parvovirus B19 infection documented serologically and by electron microscopy. Formalin fixation of bone marrow and peripheral blood smears before hematoxylin-eosin or Wright-Giemsa staining may simplify the morphological diagnosis of parvovirus B19 infection.

Atypical (7;19) translocation in acute myelomonocytic leukemia.

Chromosome studies were carried out after a 24-hour harvest of unstimulated bone marrow aspirate cell cultures from a 75-year-old male with a clinical diagnosis of acute myelomonocytic leukemia (FAB M4). Analysis of nine cells after trypsin-Giemsa banding (GTG) revealed two cell lines with a mosaic chromosome pattern, 46,XY/46,XY,t(7;19)(q22;p13.3). A review of the recent literature reveals one case of childhood ALL with a 46,XY/46,XY,t(7;19)(q11;q13) chromosome pattern [1] and a 46,XY,t(3q;11q),t(7q;19p),t(15;17)(q26;q22) in one patient with ANLL (FAB M3) [2]. The t(7;19)(q22;p13.3) seen in our case has not been reported as the sole specific clonal chromosome rearrangement in myeloid neoplasia. Interestingly, the plasminogen activator inhibitor type I, multi-drug resistance, and erythropoietin genes are located at band 7q22 and the insulin receptor gene is located at band 19p13.3. Both sites contain fragile site loci. The possible role of these fragile sites, genes, or other genes in the rearrangement can only be surmised.

Warfarin and the international normalized ratio: reducing interlaboratory effects.

In North America, the dose of warfarin has been unintentionally increased during the past two decades because of failure to recognize the effect on the anticoagulation test of less sensitive tissue thromboplastins. Although there still is some controversy, the suggested dose of warfarin has now been adjusted downward to reduce the risk of bleeding. These revised dosing recommendations incorporate the international normalized ratio (INR), which takes into account the source of thromboplastin. However, there is considerable variability in the sensitivities of thromboplastin from manufacturer to manufacturer and lot to lot. Therefore, prothrombin times (PTs) are not comparable from laboratory to laboratory without knowing the sensitivity of the thromboplastin. Unless laboratories adopt a standardized tissue thromboplastin, the PT should be reported as an INR.

Detection of rearrangement of immunoglobulin heavy chain and T-cell receptor beta chain in leukemic cells by restricted polymerase chain reaction.

Rearrangement of the immunoglobulin heavy chain and of the T-cell receptor beta subunit was analyzed by using restricted polymerase chain reaction (PCR). To differentiate between the germline configuration and the rearranged genome in a DNA sample extracted from lymphocytes, we compared the ratio of the amplified products. The intensity of amplification of the intron region (JHF) upstream of the first joining region was compared to the intensity of joining region 6 of the immunoglobulin heavy chain. The number of the amplification cycles in the PCR was designated in such a way that the ratio of JHF/JH6 was less than one in the rearranged configuration. As the concentration of clonal B-lymphocytes with the rearranged genome in the sample increased the amplification of the JHF intron proportionally decreased. We used the same approach for the two constant regions of the T-cell receptor beta chain. As one of the intron regions of the constant sequence became depleted by rearrangement so the amplification of the particular region decreased. Therefore, the absence or decreased concentration of a particular product of amplification indicated deletion and thus rearrangement of the genome in the leukemic B- or T-lymphocytes. The threshold of detection of cells with the rearranged genome on a photograph of agarose gel loaded with the particular amplified regions and staining with the ethidium bromide is less than 10% by densitometric tracing and 25-50% by visual evaluation. This novel approach allows the detection of the rearranged DNA sequences in a 2 day span. Hence, it can serve as a diagnostic tool for the identification of clonal expansion of lymphocytes in acute leukemias and lymphomas in particular and for the detection of deleted genomic regions in general.

Down's syndrome and mixed acute leukemia in infants.

The routine use of panels of monoclonal antibodies has been complementary to the French-American-British (FAB) leukemia classification, and has unmasked the occurrence of mixed acute leukemia (myeloid-lymphoid). It is widely accepted that children with Down's syndrome (DS) have a high incidence of acute leukemia. There is an extensive body of literature emphasizing the cytogenetic findings in these children. However, information as to the immunophenotype is often limited to the lymphoid surface determinants. The authors report two children with DS whose leukemic blasts were studied with a panel of 17 monoclonal antibodies (myeloid, lymphoid, and megakaryocytic) by flow cytometric examination and were classified as biphenotypic acute leukemia. The blast population coexpressed myeloid and T-cell surface markers. The lymphoid origin was ruled out on the basis of negative terminal deoxynucleotidyl transferase and molecular analysis demonstrating germline configuration for the JH and beta TCR genes.