Use of accelerometry to investigate physical activity in dogs receiving chemotherapy

OBJECTIVES

To perform a preliminary study to assess whether single-agent palliative or adjuvant chemotherapy has an impact on objectively measured physical activity in dogs.

METHODS

Fifteen dogs with neoplasia (treatment group) wore ActiGraph™ accelerometers for 5-day periods before, during and after receiving single-agent adjuvant or palliative chemotherapy. Mean 5-day total physical activity and time spent in three different intensities of activity (sedentary, light-moderate and vigorous) before, during and after receiving chemotherapy were compared to a group of 15 healthy dogs (control group). Results were also compared within the treatment group across time.

RESULTS

Prior to chemotherapy, treated dogs tended to be less active than control dogs. Treatment group dogs were slightly more active at restaging than they were prior to treatment but had similar activity levels to control dogs. Marked effects of chemotherapy on physical activity were not detected. Physical activity was slightly lower in treated dogs during chemotherapy when compared to control dogs but there was a slight increase in physical activity of treated dogs during chemotherapy when compared with pretreatment recordings. There was little change in the mean 5-day total physical activity between treated dogs during chemotherapy and at restaging but a mild decrease in time spent sedentary and increase in time spent in light-moderate activity at this comparison of time points.

CLINICAL SIGNIFICANCE

Single-agent adjuvant or palliative chemotherapy had minimal impact on physical activity levels in dogs with neoplasia.

Inhibition of HIV-1 replication with designed miRNAs expressed from RNA polymerase II promoters

Small interfering RNA (siRNA) mediates sequence-specific RNA cleavage and represents a potential approach to treat the infection of human immunodeficiency virus (HIV). Expression of a single siRNA species frequently led to the emergence of HIV escape variants. Thus, multiple siRNAs targeted to different regions in the HIV-1 genome may be required. However, overexpression of different anti-HIV siRNA genes from multiple pol III promoters can induce cell toxicity, thus may not be a viable option in the setting of human gene therapy trials. In the current study, we evaluated the strategy of using pol II promoters to drive the expression of siRNAs against HIV-1. We replaced the stem sequence in the stem-loop structure of the well-characterized miR-30a with siRNA sequences and showed that designed microRNA (miRNA) could be expressed from pol II promoters. We demonstrated efficient inhibition of HIV-1 replication with such designed miRNA, but the efficacy was directly correlated with the expression level. Both the vector copy number and the promoter strength directly affected the ability of the siRNA to inhibit HIV-1 replication. We also showed that a combination of pol II and pol III promoters to express two different siRNAs increased the efficacy against HIV-1 replication without comprising cell viability.

Drug development for stroke: importance of protecting cerebral white matter

Multiple pharmacological mechanisms have been identified over the last decade which can protect grey matter from ischaemic damage in experimental models. A large number of drugs targeted at neurotransmitter receptors and related mechanisms involved in ischaemic damage have advanced to clinical trials in stroke and head injury based on their proven ability to reduce grey matter damage in animal models. The outcome to date of the clinical trials of neuroprotective drugs has been disappointing. Although the failure to translate preclinical pharmacological insight into therapy is multifactorial, we propose that the failure to ameliorate ischaemic damage to white matter has been a major factor. The recent development of quantitative techniques to assess ischaemic damage to cellular elements in white matter, both axons and oligodendrocytes, allows rigorous evaluation of pharmacologic mechanisms which may protect white matter in ischaemia. Such pharmacological approaches provide therapeutic opportunities which are both additional or alternatives to those currently being evaluated in man.

Transfusion-associated graft-versus-host disease in immunocompetent patients: report of a fatal case associated with transfusion of blood from a second-degree relative, and a survey of predisposing factors

A patient without evident immune deficiency who received a transfusion of blood from a second-degree family member developed fatal transfusion-associated graft-versus-host disease (TA-GVHD). The donor was homozygous for an HLA haplotype for which the recipient was heterozygous (one-way HLA match). All 39 reported cases of TA-GVHD in immunocompetent patients were reviewed to ascertain the predisposing factors and to define the indications for irradiating blood for this population. HLA typing was described in 15 cases; in 13, including seven related and six unrelated donors, a one-way HLA match was present. Thirty-one (79%) of the 39 cases were reported from Japan (and 196 other cases are cited in the Japanese literature), but a one-way HLA match among unrelated donors at HLA-A, -B, -DR loci is only approximately two to four times more likely in Japanese persons than in whites. Fresh blood (< 96 hours old) was used in 29 (94%) of the 31 cases reported from Japan and in 33 (87%) of 38 cases overall (in one case, the age of the blood used was not reported). Thus, factors that appear to predispose to TA-GVHD in immunocompetent patients are a one-way HLA match, fresh blood, and, possibly, Japanese ancestry. Irradiating cellular blood components from all blood relatives of transfusion recipients will not completely eliminate the risk of TA-GVHD.

Amplification by the polymerase chain reaction of hypervariable regions of the human genome for evaluation of chimerism after bone marrow transplantation

We combined the polymerase chain reaction (PCR) with oligonucleotide hybridization as a novel and sensitive technique to evaluate posttransplant chimerism. Specific oligonucleotides for hybridization were synthesized homologous to tandemly repetitive core sequences of regions with a variable number of tandem repeats (VNTRs). Polymorphisms at such loci result from allelic differences in the number of repeats. Primers flanking the repeat region of each of the corresponding VNTRs were used for amplification. Recipient and donor pretransplant DNA and recipient posttransplant DNA were amplified. The resultant fragments were analyzed after gel electrophoresis either by hybridization in-gel or after Southern transfer. To confirm our findings, we also performed standard assays of restriction fragment length polymorphisms (RFLPs). Evaluation of 13 selected cases indicated mixed chimerism (4), complete chimerism (5), recurrence of leukemia (2), and endogenous repopulation of hematopoiesis (2) after marrow transplantation. Sensitivity of the method was determined by mixing various proportions of recipient and donor DNA; the limit of detection of the minor component in a mixture was 0.1%. PCR data correlated with RFLP data in all cases except two in which PCR proved more sensitive than RFLP. PCR amplification of VNTRs combined with oligonucleotide hybridization is a novel technique for documenting posttransplant chimerism and has advantages over RFLP analysis: high sensitivity, use of small amounts of DNA (250 ng), ease of preparation of DNA, elimination of need for restriction enzymes, and the ability to complete studies in 2 days.

Bone marrow transplantation for severe aplastic anemia. Effect of a preparative regimen of cyclophosphamide-low-dose total-lymphoid irradiation and posttransplant cyclosporine-methotrexate therapy

Twenty-nine patients with severe aplastic anemia were entered into a study of pre- and posttransplant immunosuppressive therapy for bone marrow transplantation. Four of twenty-five previously transfused recipients prepared with cyclophosphamide 200 mg/kg and total-lymphoid irradiation 3 Gy experienced graft failure, indicating that this regimen was inadequate to ensure sustained engraftment. Posttransplant treatment with cyclosporine and methotrexate resulted in an actuarial incidence for grade greater than or equal to 2 graft-versus-host disease of 22 +/- 16%. Actuarial survival was 78 +/- 15%. These data indicate that more effective treatment is necessary to prevent graft failure, but since many patients can be successfully retransplanted, overall survival is comparable to other recent studies.

Detection of herpes simplex virus in clinical specimens using a DNA probe after centrifugal inoculation of A549 cells

Two methods for detection of herpes simplex virus (HSV) in 216 clinical specimens were compared: (a) 24-well plate centrifugation using A-549 cells followed by nucleic acid hybridization (Ortho Diagnostic Systems, Inc., Raritan, NJ) after incubation for 16 to 18 h, and (b) conventional tube cell culture using A-549 cells. HSV was identified by conventional tube cell culture in 44 of 216 specimens (20%) and in 36 specimens (17%) by the centrifugation-hybridization method (P less than 0.01). HSV was recovered by tissue culture from all specimens positive by centrifugation-hybridization. The sensitivity, specificity, and positive and negative predictive values of the centrifugation-hybridization technique for detection of HSV in clinical specimens were 82, 100, 100, and 96%, respectively. Centrifugal inoculation of A549 cells in 24-well plates followed by nucleic acid hybridization after overnight incubation should not replace conventional tube cell culture for detection of HSV in clinical specimens.

Use of deoxyribonucleic acid probes in the identification of cell origin and detection of cellular contamination in human lymphoblastoid cell lines

Established lymphoblastoid cell lines have provided a valuable reference source for studying neoplastic lymphoproliferative disorders in humans. However, two major problems are associated with the establishment and growth of these cell lines: (a) the established cell line may not represent the original neoplastic clone, and (b) contamination of the established cell line with the other cell lines may occur. Lymphoblastoid cell lines "W" and "SP5" were established from splenectomy specimens of two patients with hairy cell leukemia. Both cell lines displayed B cell characteristics by immunophenotypic and Ig gene rearrangement studies. The banding patterns of the rearranged Ig genes (heavy and light chains) in the W cell line were different and in the SP5 cell line were identical with the corresponding untransformed splenic cell lines, indicating that cell line SP5 did and cell line W did not represent the original neoplastic clone. Continuous cultures of some of the subclones derived from cell line W and SP5 led to the growth of the cell lines W15T, W17T, and SP5T which all demonstrated T cell features based on immunophenotypic and T cell receptor rearrangement studies. However, the T cell receptor alpha and beta rearranged bands as well as bands generated by hybridization with highly polymorphic DNA probes p YNH24 and 0-3315-32 in these three lines and a human T cell leukemia line (CEM), were identical indicating that W15T, W17T and SP5T cell lines were contaminated with CEM. Studies of gene establishment patterns and DNA polymorphisms by Southern blotting are effective methods to establish clonal identity and to rule out cellular contamination in lymphoblastoid cell lines.

Bactericidal activity of oxacillin against beta-lactamase-hyperproducing Staphylococcus aureus

The bactericidal activity of oxacillin against beta-lactamase-hyperproducing strains of Staphylococcus aureus for which the MIC by MicroScan was 1 or 2 micrograms/ml after incubation for 24 h was evaluated by MBC studies and kill kinetics methods. MBC and kill kinetics tests were both performed using Mueller-Hinton broth (MHB), with and without 2% NaCl supplementation, and incubation at 30 and 35 degrees C. When MBC testing was performed with salt-supplemented MHB, the oxacillin MBC/MIC ratio was greater than 8 for 17 and 16 of 17 S. aureus isolates at 30 and 35 degrees C, respectively. With unsupplemented MHB, the MBC/MIC ratio was greater than 8 for nine and six strains at 30 and 35 degrees C, respectively. Five representative strains were selected for kill kinetics studies under the four different test conditions. Oxacillin appeared more bactericidal by the kill kinetics method than by MBC testing. Moreover, salt supplementation did not affect the results of kill kinetics studies as dramatically as it did the MBC results. Thus, bactericidal testing results are markedly influenced by the technique employed, and further in vivo studies are necessary to fully evaluate the efficiency of oxacillin against beta-lactamase-hyperproducing strains of S. aureus.

Evaluation of MicroScan MIC panels for detection of oxacillin-resistant staphylococci

Clinical isolates of staphylococci (420 Staphylococcus aureus isolates and 248 coagulase-negative staphylococci) were tested by both MicroScan MIC panels (MicroScan, West Sacramento, Calif.) and an oxacillin agar screen (Mueller-Hinton agar [Difco Laboratories, Detroit, Mich.] containing 6 micrograms of oxacillin per ml and 4% NaCl) to evaluate the ability of MicroScan to detect oxacillin-resistant strains. MicroScan panels and oxacillin agar screen plates were incubated at 35 degrees C for 24 h and at 30 degrees C for an additional 24 h. Endpoints were recorded at 24 and 48 h. By MicroScan, 23 (5.5%) and 30 (7%) S. aureus isolates and 161 (65%) and 162 (65%) coagulase-negative staphylococci were oxacillin resistant at 24 and 48 h, respectively. At both 24 and 48 h, 23 (5.5%) S. aureus isolates and 162 (65%) coagulase-negative staphylococci were resistant by the oxacillin agar screen. Five strains for which the oxacillin MIC was 2 or 4 micrograms/ml and eight strains resistant to oxacillin only at 48 h were further evaluated by broth macrodilution testing for oxacillin with and without clavulanic acid, by oxacillin and amoxicillin-clavulanic acid disk diffusion, and by oxacillin agar screen comparing Mueller-Hinton agars purchased from Difco and BBL Microbiology Systems, Cockeysville, Md. By this additional testing, all 10 S. aureus isolates and 1 of 3 coagulase-negative staphylococci examined produced increased amounts of beta-lactamase. One coagulase-negative staphylococcus appeared to be truly intermediately oxacillin susceptible. There was no significant difference in the rate of detection of oxacillin resistance between MicroScan and the agar screen. MicroScan panels should be incubated for 24 h only, because prolonged incubation caused strains producing excessive amounts of beta-lactamase to appear to be falsely oxacillin resistant.

Development of a single probe for documentation of chimerism following bone marrow transplantation

Although numerous genetic markers are available for studying chimerism after bone marrow transplantation (BMT), there remains a need for a practical and highly informative method that is applicable in the early posttransplantation period. Using DNA restriction-fragment-length polymorphisms (RFLPs), we have evaluated the feasibility of developing a single synthetic oligonucleotide probe to study post-BMT chimerism. We have thus tested three candidate probes, termed O-3315-32, O-3315-80, and O-AY-29, that are homologous to tandemly repetitive sequences. Our results demonstrated donor-specific and recipient-specific fragments in 11 of 11 HLA-matched sibling pairs tested using probes O-3315-32 and O-3315-80. When probe O-AY-29 was used, 14 of 17 sibling pairs showed both donor and recipient markers, one had only a recipient marker, and two were identical. We showed that each of the three synthetic probes was effective in documenting donor marrow engraftment, mixed hematopoietic chimerism, the patient's pre-BMT phenotype (by using cultured skin fibroblasts obtained after BMT), and the origin of the malignant hematopoietic cells (i.e., of donor or recipient origin) in patients who developed recurrent hematologic malignancy following BMT. Compared with the use of cloned genomic probes, there are several important advantages to the use of synthetic oligonucleotide probes in studying post-BMT chimerism. Synthetic probes have absolute hybridization specificity and can be designed to suit the purposes of an individual study, since they have adjustable specificity that can be altered by changes in the length of the probe and by changes in the hybridization temperature. A single synthetic probe analogous to several highly polymorphic loci can have a polymorphism information content sufficiently high so that all but a small percentage of BMT patients could be followed easily; for example, if a probe were complementary to three highly polymorphic unlinked loci, it would discriminate approximately 98% of sibling donor/recipient pairs. This would be accomplished using only one restriction-endonuclease digestion and only one gel electrophoresis. Since other genetic markers, e.g., red blood cell antigens, immunoglobulin allotypes, and chromosome analysis, are not uniformly informative and, in some cases, cannot be used in the early posttransplantation period, the use of synthetic oligonucleotide probes for analysis of DNA RFLP is emerging as the method of choice for studies of post-BMT chimerism. This method will allow for the development of new knowledge that has not been possible with previous methods.

Mixed hematopoietic chimerism following bone marrow transplantation for hematologic malignancies

Twenty-nine of 172 patients (17%) who received an allogeneic bone marrow transplant (BMT) from histocompatible sibling donors for hematologic malignancies were mixed hematopoietic chimeras; ie, they had a mixture of donor and host hematopoietic or lymphohematopoietic cells at greater than or equal to 14 days after transplantation. Twenty-four of the 29 mixed chimeras (83%) have remained in continuous complete remission for up to 116 months (greater than 9 years) following BMT. Four of the 29 patients (14%) have had recurrent leukemia, and 7 of the 29 (24%) have had moderate or severe graft-v-host disease (GVHD). Twelve of these 29 patients have persisted as stable mixed chimeras for greater than or equal to 2 years after BMT, whereas other patients converted to all donor-type hematopoiesis. The incidence of mixed chimerism was independent of the pretransplant regimen, the donor or recipient age (less than 20 v greater than 20 years), remission status (first complete remission of acute leukemia and first chronic phase of chronic myelocytic leukemia v later stages of disease), and type of leukemia. Our data indicate that mixed hematopoietic chimerism is not rare after BMT for hematologic malignancies and that its presence is compatible with long-term disease-free survival. Prospective studies of mixed chimerism after BMT are warranted to achieve better understanding of its biologic importance.

Increased IgG molecules bound to the surface of red blood cells of patients with sickle cell anemia

We have used the complement-fixing antibody consumption ( CFAC ) test to detect small concentrations of IgG on red blood cells from patients with hemolytic anemias that are not thought to be caused by an immune mechanism. Although patients with hereditary spherocytosis, pyruvate kinase deficiency, and mechanical hemolytic anemias generally had normal concentrations of IgG bound to their red cells (less than 25 molecules IgG per red cell), we found that 39/62 (63%) patients with sickle cell anemia had elevated values. These 39 patients had a mean of 195 and a maximum of 890 molecules of IgG per red cell. None of the patients had been transfused within the previous 90 days, and some had never been transfused. Direct antiglobulin tests were positive in only two instances and autoantibodies were not found in the serum of any patient. However, eluates from the red cells of 6 of 23 patients demonstrated antibody activity against all of a panel of normal red cells by the indirect antiglobulin test. There was no correlation between the number of IgG molecules on patients' red cells and the severity of their anemia, the incidence of painful sickle cell crises, the reticulocyte count, or with blood transfusion history. We conclude that further study of immunohematologic abnormalities in patients with sickle cell anemia is warranted, especially in view of previous reports in this population of patients with red cell autoantibodies, autoimmune hemolytic anemia, hemolytic transfusion reactions without detectable alloantibodies, and an association of some episodes of pain crises with immunologically mediated red cell destruction.

Platelet crossmatch tests using radiolabelled staphylococcal protein A or peroxidase anti-peroxidase in alloimmunized patients

Refractoriness to random-donor platelets as a result of alloimmunization remains a major problem in long-term platelet transfusion therapy despite the use of HLA-matched platelets. We have therefore studied the use of two methods for detection of platelet associated IgG as platelet crossmatch tests for the selection of platelet donors. These methods use radiolabelled staphylococcal protein A (125I-SPA) and peroxidase anti-peroxidase (PAP), respectively. One hundred and ten crossmatch tests using 125I-SPA were performed retrospectively in 18 alloimmunized patients. The results indicated that the predictive value of a positive or a negative test was 87%; the sensitivity was 73% and the specificity was 95%. Results with the PAP test were similar. The HLA types were known for 48 donor-recipient pairs. With few exceptions, there was a correlation between the results of the platelet crossmatch tests and the effectiveness of platelet transfusion regardless of the degree of HLA match. These results indicate that platelet crossmatch tests may be valuable even when closely HLA matched donors are not available. A large-scale prospective study is warranted, particularly in highly immunized patients.

Detection of IgG sensitization of red cells with 125I staphylococcal protein A

Most cases of immune hemolytic anemia are associated with a positive direct antiglobulin test. However, in some cases, the antiglobulin test is not sensitive enough to detect low levels of red-cell bound antibodies. This report describes a method using radiolabelled purified staphylococcal protein A which is capable of detecting IgG sensitization of red cells beyond the threshold of serologic techniques. It is less cumbersome than previously described methods and does not require antibody purification procedures. Its effectiveness was demonstrated for the detection of red-cell alloantibodies and in evaluation of patients with acquired hemolytic anemias associated with a negative direct antiglobulin test.

Complement activation by Coccidioides immitis: in vitro and clinical studies

Mycelial- or spherule-phase derivatives of Coccidioides immitis caused a decrease in vitro of total hemolytic complement in serum from a nonsensitized person. Activation involved both classic and alternative pathways as shown by deprssion of hemolytic C4 and by generation of products of activation of components C3, C4, and factor B. In addition, functional complement activity or immunoreactive levels of complement components or both were measured in 23 patients with self-limited or disseminated coccidioidomycosis. Low total hemolytic complement was found in nine, usually during the early phase of primary illness, and was transient. Hemolytic C4 was low, and the effect of inulin to decrease complement levels was blunted, suggested both classic and alternative pathways may be deficient. However, associated depression of immunoreactive levels of components assayed (C3, C4, C5, factor B, and properdin) was not consistently found. This disparity raises the possibility of enhanced in vitro inactivation analogous to activation by immune complexes.

The relationship between hemolytic and immunodiffusion methods for measurement of C4 in patients with immunologic disorders

A comparison of radial immunodiffusion and functional (hemolytic) assays for C4 revealed a highly significant correlation between the two methods in patients with a variety of immunologic disorders. Immunodiffusion technics are more convenient than hemolytic assays for most clinical laboratories. C4 assays are useful for the presumptive diagnosis of hereditary angioneurotic edema, whereas C3 is usually normal in such patients. C4 is usually more sensitive than C3 in a variety of immunologic disorders, although in some patients the opposite is true, especially in hypocomplementemic nephritis.