Antimicrobial resistance of staphylococci and streptococci isolated from dogs.

A study was conducted for the examination of bacterial species isolated in dogs from Animal Clinics of Nanjing Agricultural University, China. Forty nasal swabs were taken from dogs having respiratory signs. Staphylococcus pseudintermedius was the most frequently isolated pathogen (37.50 %) followed by Staphylococcus aureus (18.75%), Streptococcus pluranimalium (10.93%), Streptococcus canis (9.37%), Staphylococcus schleiferi (9.37%), Staphylococcus intermedius (6.25%), Staphylococcus cohnii (4.71%) and Staphylococcus hominis (3.12%). S. pseudintermedius and S. pluranimalium were subjected to commonly used antibiotics for determination of resistant drugs. Antimicrobial resistance in S. pseudintermedius was common in gentamicin (70.83%) and tetracycline (50%) while in S. pluranimalium was common in enrofloxacin (71.42%) and gentamicin (57.14%).

Antimicrobial resistance of staphylococci and streptococci isolated from dogs

@#A study was conducted for the examination of bacterial species isolated in dogs from Animal Clinics of Nanjing Agricultural University, China. Forty nasal swabs were taken from dogs having respiratory signs. Staphylococcus pseudintermedius was the most frequently isolated pathogen (37.50 %) followed by Staphylococcus aureus (18.75%), Streptococcus pluranimalium (10.93%), Streptococcus canis (9.37%), Staphylococcus schleiferi (9.37%), Staphylococcus intermedius (6.25%), Staphylococcus cohnii (4.71%) and Staphylococcus hominis (3.12%). S. pseudintermedius and S. pluranimalium were subjected to commonly used antibiotics for determination of resistant drugs. Antimicrobial resistance in S. pseudintermedius was common in gentamicin (70.83%) and tetracycline (50%) while in S. pluranimalium was common in enrofloxacin (71.42%) and gentamicin (57.14%).

Interleukin-3 in hematology and oncology: current state of knowledge and future directions.

Interleukin (IL)-3 is a multipotent hematopoietic growth factor produced by activated T cells, monocytes/macrophages and stroma cells. The human IL-3 gene is located on chromosome 5 near segment 5q31. The high-affinity receptor for human IL-3 is composed of alpha and beta subunits. IL-3 shares a common beta subunit with granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-5; this subunit has been mapped to chromosome 22q13.1. The biological effects of IL-3 have been studied in human and murine hematopoietic cell lines and normal human marrow cells. Addition of IL-3 to the culture medium induces proliferation, maturation and probably self-renewal of pluripotent hematopoietic stem cells and cells of myeloid, erythroid and megakaryocytic lineages. Human IL-3 was cloned in 1986, and since then various clinical trials have assessed the in vivo potential of recombinant human (rhIL-3). Initial results of phase I/II studies of IL-3 at a dose of 5-10 microg/kg subcutaneously daily for 5-10 days in patients with relapsed lymphomas, small-cell lung cancer, breast cancer and ovarian cancer showed that post-chemotherapy application of IL-3 reduces chemotherapy delays and induces faster regeneration of granulocytes and platelets. However, these results were not confirmed in phase III studies. The role of IL-3 alone in the treatment of myelodysplastic syndromes (MDS), aplastic anemia (AA) and other bone marrow failure disorders have also been disappointing. However, preliminary studies of IL-3 in combination with chemotherapeutic agents and immunosuppression have demonstrated encouraging results in patients with MDS and AA respectively. The therapeutic potential of IL-3 in peripheral blood stem cell (PBSC) harvesting and priming of stem cells before harvest is beginning to be identified. Initial results of IL-3 combination with GM-CSF or later-acting growth factors such as granulocyte colony-stimulating factor (G-CSF) have yielded larger amounts of PBSC during harvesting. In recent years, the availability of synthetic IL-3 receptor (IL-3R) agonists and similar chimeric molecules with greater in vitro biological activity and fewer inflammatory side-effects has extended our options to employ and compare these molecules and rhIL-3 for the prevention of chemotherapy-induced myelosuppression. The role of IL-3 and IL-3R agonists in ex vivo expansion of stem cells, dendritic cell development and gene transfer requires further evaluation. It appears that future application of IL-3 in combination with other cytokines is an attractive way forward in the prevention of treatment-related mortality and morbidity in oncology patients. It also shows prospects for the development of new therapeutic strategies for dose escalation and immune modulation for cancer patients with relapsed and resistant disease.

Interleukin-3: Promises and Perspectives.

Interleukin-3 (IL-3) is a multipotent hematopoietic growth factor produced by activated T-cells, monocytes/macrophages and stroma cells. Human IL-3 gene is located on chromosome 5 near segment 5q31. The high affinity receptor for human IL-3 is composed of alpha and beta subunits. IL-3 shares common beta subunit with GM-CSF and IL-5 which has been mapped to chromosome 22q13.1. The biological effects of IL-3 have been studied in human and murine hematopoietic cell lines and normal human bone marrow cells. Addition of IL-3 to the culture medium induces proliferation, maturation and probably self renewal of pluripotent hematopoietic stem cells and cells of myeloid, erythroid and megakaryocytic lineages. Various clinical trials have assessed the in vivo potential of recombinant human interleukin 3 (rhIL-3). Initial results of phase I/II studies of IL-3 at a dose of 5-10 ug/kg subcutaneous (s/c) daily for 5-10 days in patients with relapsed lymphomas, small cell lung cancer, breast cancer and ovarian cancer have shown that post-chemotherapy application of IL-3 reduces chemotherapy delays and induces faster regeneration of granulocytes and platelets. However, these results were not confirmed in phase III studies. The role of IL-3 alone in the treatment of myelodysplastic syndromes (MDS), aplastic anemia (AA) and other bone marrow failure disorders have also been disappointing. However, preliminary studies of IL-3 in combination with chemotherapeutic agents and immunosuppression have demonstrated encouraging results in patients with MDS and aplastic anemia respectively. The therapeutic potential of IL-3 in peripheral blood stem cell harvesting and priming of stem cells before harvest is beginning to be identified. Initial results of IL-3 in combination with granulocyte macrophage colony stimulating factor (GM-CSF) or later acting growth factor like granulocyte colony stimulating factor (G-CSF) have yielded larger amounts of peripheral blood stem cells during PBSC harvesting. This approach and application of IL-3 with cocktail of other cytokines for ex-vivo expansion of stem cells, dendritic cell development and gene transfer requires further evaluation. The role of IL-3 in murine models of antiphospholipid syndrome (APLS) for prevention of recurrent abortion remains experimental and warrants careful assessment of adverse effects of IL-3 therapy on pregnant woman and fetus. The exact therapeutic role of IL-3 in oncology and nononcology patients is beginning to be identified. It appears that future application of IL-3 in combination with other cytokines is an attractive way forward in the prevention of treatment related mortality and morbidity in oncology patients. It also holds prospects for development of new therapeutic strategies for dose escalation and immune modulation for relapsed cancer patients.

Primary myelodysplastic syndromes: diagnostic and prognostic significance of immunohistochemical assessment of bone marrow biopsies.

Material from 63 cases with primary myelodysplastic syndromes (P-MDS) (French-American-British [FAB] types: refractory anemia [RA] = 21; RA with ring sideroblasts [RARS] = 8; RA with excess of blasts (RAEB) = 10; RAEB in transformation (RAEBt) = 6; chronic myelomonocytic leukemia [CMML] = 10 and unclassifiable = 8, ie, bone marrow aspiration was inadequate and stringent FAB criteria were not applicable) was analyzed for bone marrow histologic and immunohistochemical patterns. Standard Giemsa, hematoxylin and eosin (H&E) and reticulin stains were used for morphologic assessment. To identify the cell lineage precisely, chloroacetate esterase staining and an indirect immunoperoxidase technique using mouse monoclonal antibodies CD15, CD68, HLA-DR, and rabbit polyclonal CD3 and UEA-1 (lectin) was developed on formalin-fixed paraffin embedded bone marrow biopsies (BMB). The immunohistochemical assessment permitted accurate identification of dysplastic features such as mononuclear and binuclear megakaryocytes, Pelger-Huet neutrophils, and binuclear erythroblasts. Additional bone marrow histologic and immunohistochemical features observed were heterogeneity of immunohistochemical staining in various cell lineages, megakaryocytic emperipolesis, alteration of bone marrow microarchitecture, intravascular clusters of hematopoietic cells, and the types of benign lymphoid aggregates. The nature of abnormally localized immature precursors (ALIP) was discerned. Three types of clusters of immature cells were found that were difficult to distinguish on Giemsa and H&E morphology, these were erythroid aggregates (n = 18); megakaryocytic aggregates (n = 4), and immature granulocytic and monocytic aggregates (n = 32). The bone marrow histologic and immunohistologic patterns permitted the identification of four groups of clinical relevance: Group 1, cases with predominant erythroid hyperplasia and without ALIP (n = 15); group 2, cases with prominent myeloid hyperplasia and presence of ALIP (n = 32); group 3, cases with hypoplastic MDS (n = 10); and group 4, cases with hyperfibrotic MDS (n = 6). Statistical analysis showed a significant difference in survival and leukemic transformation between groups 1, 2, 3, and 4, with cases in group 2 showing the worst prognosis with early death due to increased propensity to leukemic transformation and cytopenia-related complications (P less than .0001). We conclude that immunohistochemistry is feasible on routinely processed BMB and the information obtained is of diagnostic and prognostic importance in P-MDS. The phenotype of ALIP varies with the morphologic and histologic subtypes of MDS and the term should be reserved for cases in whom the clusters in the intertrabecular region are of myeloid (granulocytic and monocytic) lineage on immunohistochemistry.

Cross-lineage rearrangement of antigen receptor genes in atypical chronic myeloid leukemia.

The configuration of immunoglobulin (Ig) and T-cell receptor (TCR) genes was investigated in a case of atypical chronic myeloid leukemia (aCML) lacking a cytogenetically detectable Philadelphia chromosome and molecular evidence of breakpoint cluster region (bcr) rearrangement as determined by 5' and 3' bcr gene probes. Dual clonal rearrangement of Ig-heavy (H) and TCR-delta chain genes was identified. The genes for TCR-gamma and beta chain as well as Ig-kappa (k) chain were in germline configuration. These findings indicate transformation to have occurred in a hemopoietic stem cell with the capacity for antigen receptor gene rearrangement. The demonstration of cross-lineage rearrangement of both Ig and TCR genes lends support to evidence from G6PD alloenzyme studies that the target of transformation in aCML is an early stem cell not yet irreversibly committed to myeloid differentiation. Further studies are indicated to ascertain whether antigen receptor gene rearrangement constitutes a molecular marker useful in the diagnosis of aCML.

Abnormal localization of immature precursors (ALIP) in the bone marrow of myelodysplastic syndromes: current state of knowledge and future directions.

It has been suggested that the occurrence of abnormal localization of immature precursors (ALIP) in the bone marrow biopsy (BMB) may be of diagnostic and prognostic significance in myelodysplastic syndromes (MDS). The recognition of ALIP has been based exclusively on bone marrow histological appearances. During the last decade technical advances have led to the widespread use of various immunophenotypic markers for the diagnostic and prognostic purposes which has contributed enormously in understanding the development of haemopoietic cells and the cellular origin of various haematological malignancies. In addition proliferation antigens, growth factors, oncogenes, anti-oncogenes and other biological discoveries have opened new vistas to our knowledge of the normal and neoplastic growth processes. Despite this, the precise nature of ALIP and their significance in relation to the aetiopathogenesis and evolution of MDS remains unclear. Indeed the diagnostic value of ALIP in MDS is debatable. Furthermore, the precise cell lineages which comprise ALIP are not defined. The purpose of this review is to address these issues and to incorporate our new findings on the histological and immunophenotypic characterization of immature cell aggregates.

Multicentric reticulohistiocytosis. Detailed immunophenotyping confirms macrophage origin.

A case study of multicentric reticulohistiocytosis is presented with extensive immunohistochemical studies of the infiltrate in both paraffin and cryostat sections. These studies showed that the cells are of monocyte/macrophage origin. B- and T-cell gene rearrangement analysis of multicentric reticulohistiocytosis was also performed and showed a germline configuration.