Biomedical subjects

D Myerson

Publications and source records attributed to D Myerson.

At least 37 records · Page 2Linked to original sources

PubMed1997

Acute pancreatitis in marrow transplant patients: prevalence at autopsy and risk factor analysis.

Pancreatitis has been described as an infrequent complication of marrow transplantation. This study investigated the prevalence of pancreatitis at autopsy in marrow transplant patients and determined risk factors for its development. We reviewed consecutive autopsy reports from 1991 to 1993. Medical records and laboratory reports were reviewed for analysis of clinical variables. Autopsy findings and clinical variables were correlated with the autopsy diagnosis of pancreatitis. Pancreatitis was found in 51 of 184 (28%) patients at autopsy. Of those with pancreatitis, 35% had abdominal pain, 10% had measurements of serum pancreatic enzymes, and 20% had abdominal imaging studies in the week prior to death. By univariable analysis, risk factors associated with development of pancreatitis included clinical grades 3 and 4 GVHD, GVHD at autopsy, liver GVHD at autopsy, major infection at autopsy, and increasing days of survival. By multivariable analysis, independent risk factors for its development included any GVHD at autopsy, increasing length of survival after transplantation, and major infection at autopsy. We conclude that pancreatitis is a common but often subclinical complication of marrow transplantation. Its development may be associated with a high prevalence of biliary sludge and prolonged treatment of GVHD with cyclosporine and prednisone.

Abdominal Pain↗

PubMed1997

Circulating cytomegalovirus (CMV)-infected endothelial cells in marrow transplant patients with CMV disease and CMV infection.

Circulating cytomegalovirus (CMV)-infected endothelial cells (CCIC) have been found in immunocompromised patients with CMV disease and have been associated with disease severity. The frequency of CCIC in marrow transplant recipients was studied to determine its use for distinguishing between CMV pneumonia and asymptomatic CMV infection. CCIC were found in 13 (81%) of 16 patients with CMV pneumonia (5/6 without copathogen; 7/10 with copathogen) and in 10 (50%) of 20 patients with asymptomatic CMV antigenemia at different levels. There was no statistically significant association for the incidence nor the quantitative level of CCIC in patients with asymptomatic CMV antigenemia, CMV pneumonia with or without copathogen, or different levels of CMV virus load measured by antigenemia. The high incidence and quantitative level of CCIC in patients without clinical disease suggests a role for CCIC in CMV dissemination rather than its being a specific marker of organ or tissue damage after marrow transplantation.

Adolescent↗

PubMed1997

Cytomegalovirus disease occurring before engraftment in marrow transplant recipients.

Little information is available regarding the incidence, clinical course, and response to treatment of cytomegalovirus (CMV) disease that occurs before engraftment in marrow transplant recipients. We identified 25 patients over a 12.5 year period who developed CMV disease before achieving engraftment. Twelve cases were diagnosed during life, and 13 cases were diagnosed at autopsy. The lung was the site most commonly involved (92% of patients), and most of the patients (92%) were CMV seropositive. Significant copathogens were identified in 45% of the patients. All nine patients with CMV pneumonia died within 6 weeks after the diagnosis was made, and one of two patients with gastrointestinal disease also died 6 weeks after the diagnosis was made despite the administration of antiviral therapy. Surveillance cultures were not helpful in identifying patients at risk for disease. Histopathological examination of the lungs of patients with early CMV pneumonia only infrequently showed typical CMV lesions. In conclusion, CMV disease occurring before engraftment in CMV-seropositive recipients was uncommon, was frequently associated with the presence of other opportunistic pathogens, and was associated with a high fatality rate. Better diagnostic methods to identify patients at risk are required in the preengraftment period.

Adolescent↗

PubMed1996

Prevention of transmission of hepatitis C virus in bone marrow transplantation by treating the donor with alpha-interferon.

Transmission of hepatitis C virus (HCV) in the setting of allogeneic bone marrow transplantation can occur through an infected marrow donor. Prevention of transmission may reduce the risks of peritransplant complications. We describe a 43-year-old patient with chronic myelogenous leukemia whose HLA-identical donor was found to be HCV antibody positive and HCV RNA positive by polymerase chain reaction (PCR). The patient was HCV antibody negative and HCV RNA negative by PCR of the serum. For 6 months before bone marrow transplantation, the donor was treated with alpha-interferon at a standard dose. After 3 months, HCV RNA was no longer detectable by PCR. Interferon was discontinued 1 week before harvest. Bone marrow cellularity was normal. Engraftment was prompt. The recipient's serum remained negative for HCV RNA at 1, 3, 5, and 10 months after transplantation. Hepatitis C transmission from a viremic donor to an HCV-seronegative recipient may be preventable by treating the donor with alpha-interferon.

Adult↗

PubMed1996

Cytomegalovirus pp65 antigenemia-guided early treatment with ganciclovir versus ganciclovir at engraftment after allogeneic marrow transplantation: a randomized double-blind study.

To determine whether cytomegalovirus (CMV) antigenemiaguided ganciclovir treatment may be as effective, may require less treatment, and thus may cause less marrow toxicity than ganciclovir administered at engraftment, 226 marrow transplant recipients were randomized at engraftment to receive placebo (antigenemia-ganciclovir group) or ganciclovir (ganciclovir group) until day 100 in a double-blind study. In patients with antigenemia of 3 or more positive cells in 2 slides and/or viremia, study drug was discontinued and ganciclovir was started for at least 3 weeks or until negative CMV antigenemia and resumed only if antigenemia recurred. More patients in the antigenemia-ganciclovir group developed CMV disease before day 100 after transplantation compared with the ganciclovir group (14% v 2.7%, P = .002). Of the 16 patients with CMV disease before day 100 in the antigenemia-ganciclovir group, 10 (8.8%) had disease before or during the first episode of antigenemia and 6 (5.3%) developed disease after discontinuation of ganciclovir. Untreated low-grade antigenemia progressed to CMV disease in 19% of patients with grade 3-4 compared with 0% of patients with grade 0-2 acute graft-versus-host disease (P = .04). There was no significant difference in CMV disease by day 180 after transplantation and thereafter. CMV-related death, transplant survival, and neutropenia were not significantly different between the groups. In the ganciclovir group, more invasive fungal infections occurred (P = .03) and more ganciclovir was used (P < .0001). Thus, delaying the start of ganciclovir until highgrade antigenemia and discontinuing ganciclovir based on negative antigenemia results in more CMV disease by day 100 than ganciclovir administered at engraftment. However, ganciclovir at engraftment is associated with more early invasive fungal infections and more late CMV disease resulting in similar survival rates.

Adolescent↗

PubMed1996

Recombinant human ligand for MPL, megakaryocyte growth and development factor (MGDF), stimulates thrombopoiesis in vivo in normal and myelosuppressed baboons.

Megakaryocyte growth and development factor (MGDF) is a ligand for c-mpl and a member of the hematopoietic growth factor superfamily. Recombinant murine MGDF specifically stimulates thrombopoiesis in mice. Recombinant human (rHu) MGDF stimulates megakaryocytic differentiation of baboon CD34+ marrow cells in vitro. Therefore, we determined the in vivo biological effects of rHuMGDF administered to normal baboons in the absence and presence of myelosuppression with 5-fluorouracil (5-FU). rHuMGDF was administered to normal baboons as a single s.c. injection at doses of 1, 10, 25 and 50 micrograms/kg/day for 10 days and, as a control, heat-inactivated MGDF was administered at a dose of 10 micrograms/kg/day. Platelet counts were markedly increased in all animals administered native rHuMGDF but not in animals given heat-inactivated rHuMGDF. Platelet counts began to increase between three and six days after starting rHuMGDF administration and the maximum average increases were 1.7-, 3.4-, 5.1- and 4.0-fold above baseline in animals administered 1, 10, 25 and 50 micrograms/kg/day, respectively. Maximum platelet counts were reached between 7 and 10 days after starting rHuMGDF and maintained for four days after the last dose. Thereafter, platelet counts decreased, reaching stable pretreatment values between 11 and 14 days after the last dose of rHuMGDF. No changes in red cell mass, peripheral blood white blood cell counts or differentials were observed during rHuMGDF treatment. For animals administered 10, 25 and 50 micrograms/kg/day of rHuMGDF, megakaryocytes increased more than threefold in marrow, were markedly enlarged, and had increased numbers of lobes. Overall marrow cellularity remained unchanged, as did red cell and white cell morphology. No marrow fibrosis was detected. Progenitor cells were not increased in marrow but did increase modestly in the peripheral blood, associated with increased numbers of CD34+ cells in the circulation. Following a single dose of 5-FU (120 mg/kg) animals were given either saline or pegylated (PEG) rHuMGDF (25 micrograms/kg/day) for 14 days. Platelet counts recovered to baseline by 13.8 +/- 1.8 days for PEG-rHuMGDF-treated baboons compared with 16.8 +/- 0.6 days for saline treated controls. Marrow biopsies revealed more rapid recovery of overall marrow cellularity and megakaryocytes in PEG-rHuMGDF-treated animals compared with controls. Thus, rHuMGDF specifically stimulates thrombopoiesis in normal and myelosuppressed baboons. rHuMGDF may be useful for stimulating thrombopoiesis in humans in clinical settings after myelosuppression.

Animals↗

PubMed1996

Facilitation of DLA-incompatible marrow grafts by donor-specific serum transferrin?

Studies in mice have shown that donor-specific plasma transferrin (TF) given to the recipient in the peritransplant period facilitates engraftment of marrow from histoincompatible donors. Dogs given 920 cGy of total body irradiation (TBI) and infused with marrow from an unrelated major histocompatibility complex (DLA) different donor generally fail to engraft; only approximately 20% of dogs achieve sustained engraftment. We have now investigated in this model whether the infusion of donor-specific plasma TF would facilitate engraftment. Ten dogs were given TBI, followed at 23 h by an intravenous dose of TF, at 24 h by marrow from the same donor, and another dose of TF at 48 h; six dogs also received postgrafting methotrexate (MTX). Seven dogs (three of four without MTX, four of six with MTX) had sustained engraftment, and three dogs failed to engraft. A single dog given third-party TF failed to engraft. Among five dogs not given TF two achieved sustained engraftment. This pilot study suggests that donor-specific TF facilitates engraftment of DLA-incompatible marrow. Further studies are warranted.

Animals↗

PubMed1996

Hepatitis C virus (HCV) infection in bone marrow transplant patients after transfusions from anti-HCV-positive blood donors.

In March 1992, 12 bone marrow transplant patients at the Fred Hutchinson Cancer Research Center received blood components from donors who were anti-HCV-nonreactive by first generation ELISA but whose serum later tested anti-HCV-reactive to a second generation ELISA. All these blood components were further tested for anti-HCV using a second-generation RIBA and for HCV RNA by polymerase chain reaction. Recipient sera were tested for HCV RNA prior to and following blood component infusion. Blood components from four donors were positive for HCV RNA. All recipients of HCV RNA-positive blood components became viremic on the first day tested post-infusion. In addition, two recipients of HCV RNA-negative blood components tested HCV RNA-positive both pre- and post-infusion. Viremia persisted up to the time of death or day 100 in five of the six patients who were HCV RNA-positive post-transplant. No HCV RNA-positive recipient developed symptomatic acute hepatitis, and only two had aminotransferase elevations consistent with chronic hepatitis. We conclude that HCV RNA-positivity in blood components accurately predicts transmission of virus. Infection with HCV did not adversely affect short-term patient outcome following bone marrow transplantation.

Acute Disease↗

PubMed1996

High-dose busulfan and cyclophosphamide followed by autologous transplantation in patients with advanced breast cancer.

This study was conducted to evaluate the efficacy of high-dose busulfan (BU) and cyclophosphamide (CY) in patients undergoing autologous hematopoietic stem cell transplantation for metastatic breast cancer. Twenty-two patients with stage IV breast cancer underwent autologous marrow (n = 13), peripheral blood stem cell (PBSC) (n = 6) or marrow plus PBSC (n = 3) transplantation following BU (14-16 mg/kg) and CY (120-180 mg/kg). Of 22 patients, 18 had refractory relapse, one had primary refractory disease, two had responding relapse and one had no evidence of disease (NED) at the time of transplant. Eight patients had bone only disease, six had bone plus visceral disease, and eight had loco-regional recurrent disease. The median time for diagnosis to transplant was 1124 days (range 210-2582). Staging for evaluation of response was performed 4-6 months after transplantation. Six patients were not evaluable (NE) for response because of NED at transplant (n = 1) or early death due to transplant-related complications (n = 5) (one of RSV interstitial pneumonia, two of fungal infection and two of regimen-related toxicities) occurring at a median of 17 days (range 14-59) post-transplant. The patient who was NED at time of transplant is still NED on day 336 post-transplant. Seven of the 16 evaluable patients achieved a complete response (CR) (44%), five achieved a partial response (PR) (31%) and five had no response (NR), with an overall response rate of 75%. Five of 18 (28%) patients treated in refractory relapse, and both patients treated in responding relapse achieved a CR. Of the seven patients who achieved CR, three are alive and disease-free on days 204, 276 and 752 and three relapsed on days 209, 715 and 1127 post-transplant. One patient in CR died of aspergillus pneumonia on day 306 post-transplant. The median day to progression in five patients who achieved a PR after transplantation was 335 (range 144-507). The probabilities of survival and event-free survival (EFS) at 2 years was 0.22 and 0.15, respectively for all 22 patients. The probability of EFS at 2 years for the eight patients achieving CR (including one patient who was NED at transplant) was 0.33. The probabilities of overall survival at 2 years in patients who did and did not achieve a CR after transplantation was 0.63 and 0.14, respectively (P = 0.004). These data suggest that high-dose BU-CY followed by autologous stem cell transplantation is an effective regimen in patients with advanced breast cancer demonstrating that BU is an active agent in this disease and could be incorporated into treatment regimens requiring hematopoietic stem cell support.

Adult↗

PubMed1996

Marrow transplantation for hepatitis-associated aplastic anemia: a follow-up of long-term survivors.

Between 1971 and 1989 we have treated 19 patients with hepatitis-associated aplastic anemia by marrow transplantation from their HLA-identical siblings following conditioning with 200 mg/kg cyclophosphamide (Cy) administered over a period of 4 days. One patient failed to engraft by day 34 and was given a second transplantation. He died from infection 15 days after the second transplantation. Eighteen patients had sustained engraftment. Six patients developed acute graft-vs.-host disease (GVHD) and two of these patients died 2.8 and 3.3 months after transplantation. Fifteen patients are surviving 4 to 24 (median 13) years after transplantation, while one patient died in a car accident 17 years after successful transplantation. Six of the surviving patients developed chronic GVHD. Two of the patients with chronic GVHD had preceding acute GVHD and four did not. Five of the six patients with chronic GVHD received donor buffy coat cells in addition to the marrow inoculum to prevent graft rejection. Twelve of the 15 surviving patients have Karnofsky performance scores of 100%. One patient, living more than 4 years after transplantation, has a Karnofsky score of 40% because of persistent cognitive deficits following non-A, non-B hepatitis with hepatic coma. Two patients developed hepatitis C infection 12 and 18 years after transplantation, respectively. Except for mild fatigue and mildly elevated liver function tests, these patients are doing well with Karnofsky performance scores between 95 and 100%. One patient developed severe coronary artery disease 10 years after transplantation, decreasing his Karnofsky performance score to 80%. Serum samples before and after transplantation from 13 patients were tested for hepatitis B virus (HBV) DNA and hepatitis C virus (HCV) RNA by polymerase chain reaction (PCR). Only one patient tested positive for HCV RNA before transplantation. Seven of 15 sera were hepatitis C RNA-positive posttransplantation, but only one of these patients has developed active hepatitis C. All 13 patients were were negative for hepatitis B surface antigen and HBV DNA. Only one patient had IgM antibodies against hepatitis A virus (HAV) before transplantation, which suggested HAV infection. Hepatitis-associated aplastic anemia apparently was caused in most patients by a non-A, non-B, non-C agent. HLA-identical marrow transplantation for hepatitis-associated aplastic anemia with Cy as conditioning regimen is well-tolerated and has a long-term event-free survival in excess of 80%, not different from results of marrow transplantations for aplastic anemia of other etiologies.

Adolescent↗

PubMed1995

In situ hybridization analysis of the Y chromosome in gonadoblastoma.

Gonadoblastoma is a rare tumor arising in the streak gonads of about 30% of 46,XY sex-reversed females. Because gonadoblastoma develops only in patients who have Y-chromosome material and dysgenetic gonads, it has been hypothesized that positive expression of a gene (or genes) on the Y chromosome (GBY) is involved in the etiology of the tumor. To examine the Y chromosome directly in tumors, we performed nonisotopic in situ hybridization of a biotin-labeled Y-specific probe for the DYZI locus on formalin-fixed, paraffin-embedded sections of tumor samples from four different patients. After hybridization to DYZI, the Y chromosome was found to be present in all gonadoblastoma foci in the four patients studied, and the gonadoblastoma foci showed an average of 85% cell nuclei positive for the Y chromosome on tissue sections. Normal male and female control tissues showed an average of 78% and 0% positive nuclei, respectively. One patient with bilateral gonadoblastoma had previously been shown to be mosaic, with a 45,X/46,XY karyotype in lymphocytes, skin fibroblasts, and cultures from both gonads. Examination of sections of this patient's gonads showed 79% positive nuclei within the gonadoblastoma foci, whereas the nontumor stromal tissue had 19% positive nuclei. These results indicate that, in this mosaic gonad, tumor foci developed only from cells that had a Y chromosome. Our results support the hypothesis that there is a GBY locus on the Y chromosome and that the Y chromosome is retained in the gonadoblastoma foci during the development of the tumor.

Adolescent↗

PubMed1995

Fungal liver infection in marrow transplant recipients: prevalence at autopsy, predisposing factors, and clinical features.

To determine the prevalence of fungal liver infection at autopsy in marrow transplant recipients, we reviewed autopsy results for the period 1980-1989. Cases were compared to randomly chosen autopsied controls without fungal infection. Fungal liver infection was found in 67 (9%) of 731 patients. Fungal cultures of liver lesions were positive for 34 of 67 patients, most of whom had been culture-positive for the same fungal species (largely Candida) during life. Multivariate analysis revealed that independent predictors of fungal liver infection were deep fungal infection after transplantation (RR, 35), colonization or superficial infection after transplantation (RR, 13), and severe liver dysfunction caused by veno-occlusive disease of the liver and/or graft-versus-host disease (RR, 7). Clinical and laboratory findings during the last month of life revealed no differences between cases and controls. Liver imaging studies performed during the last 15 days of life had a sensitivity of only 18% for detecting fungal liver lesions.

Adult↗

PubMed1994

Marrow transplantation from hepatitis C virus seropositive donors: transmission rate and clinical course.

Bone marrow transplant recipients are at risk for acquiring hepatitis C infection from the donated marrow. Twelve patients who were hepatitis C virus (HCV) RNA-negative pretransplant received marrow from anti-HCV seropositive donors. HCV RNA was present in the sera of seven of these donors. After transplant, serial serum specimens were obtained from all marrow recipients for determination of HCV RNA and aminotransferase levels. All seven recipients of marrow from HCV RNA-positive donors were HCV RNA-positive after marrow infusion; none cleared virus from the serum. All five recipients of marrow from anti-HCV seropositive, HCV RNA-negative donors remained free of HCV RNA in serum up to day 100. Abnormal serum aminotransferases were common in both HCV RNA-negative and HCV RNA-positive marrow recipients. One HCV-infected recipient developed marked elevation in aminotransferases after immunosuppressive drugs were stopped. We conclude that the presence of HCV RNA in the serum of marrow donors is an accurate predictor of HCV infection in marrow recipients. The acute infection was subclinical in all patients. The long-term risk of chronic hepatitis C virus infection in these patients remains to be determined.

Adult↗

PubMed1994

In vivo synergy between recombinant human stem cell factor and recombinant human granulocyte colony-stimulating factor in baboons enhanced circulation of progenitor cells.

Recombinant human stem cell factor (rhSCF) and recombinant human granulocyte colony-stimulating factor (rhG-CSF) are synergistic in vitro in stimulating the proliferation of hematopoietic progenitor cells and their precursors. We examined the in vivo synergy of rhSCF with rhG-CSF for stimulating hematopoiesis in vivo in baboons. Administration of low-dose (LD) rhSCF (25 micrograms/kg) alone did not stimulate changes in circulating WBCs. In comparison, administration of LD rhSCF in combination with rhG-CSF at 10 micrograms/kg or 100 micrograms/kg stimulated increases in circulating WBCs of multiple types up to twofold higher than was stimulated by administration of the same dose of rhG-CSF alone. When the dose of rhG-CSF is increased to 250 micrograms/kg, the administration of LD rhSCF does not further increase the circulating WBC counts. Administration of LD rhSCF in combination with rhG-CSF also stimulated increased circulation of hematopoietic progenitors. LD rhSCF alone stimulated less of an increase in circulating progenitors, per milliliter of blood, than did administration of rhG-CSF alone at 100 micrograms/kg. Baboons administered LD rhSCF together with rhG-CSF at 10, 100, or 250 micrograms/kg had 3.5- to 16-fold higher numbers per milliliter of blood of progenitors cells of multiple types, including colony-forming units granulocyte/macrophage (CFU-GM), burst-forming unit-erythroid (BFU-E), and colony-forming and burst-forming units-megakaryocyte (CFU-MK and BFU-MK) compared with animals given the same dose of rhG-CSF without rhSCF, regardless of the rhG-CSF dose. The increased circulation of progenitor cells stimulated by the combination of rhSCF plus rhG-CSF was not necessarily directly related to the increase in WBCs, as this effect on peripheral blood progenitors was observed even at an rhG-CSF dose of 250 micrograms/kg, where coadministration of LD rhSCF did not further increase WBC counts. Administration of very-low-dose rhSCF (2.5 micrograms/kg) with rhG-CSF, 10 micrograms/kg, did not stimulate increases in circulating WBCs, but did increase the number of megakaryocyte progenitor cells in blood compared with rhG-CSF alone. LD rhSCF administered alone for 7 days before rhG-CSF did not result in increased levels of circulating WBCs or progenitors compared with rhG-CSF alone. Thus, the synergistic effects of rhSCF with rhG-CSF were both dose- and time-dependent. The doses of rhSCF used in these studies have been tolerated in vivo in humans.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1994

Rescue from anti-MHC class II antibody-mediated marrow graft failure by c-kit ligand.

Dogs given 920 cGy of total body irradiation (TBI) followed by autologous marrow infusion uniformly achieve sustained hematopoietic reconstitution. We have previously shown that administration of the anti-MHC class II monoclonal antibody (MoAb) H81.98.21 (IgG2a) at 0.6 mg/kg/d immediately after transplantation results in delayed graft failure. A second noncrossblocking anti-MHC class II MoAb, B1F6, of the same isotype, at the same dose, did not interfere with sustained engraftment, suggesting that the observed effect was epitope dependent. Although higher concentrations of B1F6 were required, in the present study both MoAbs interfered with the propagation of long-term marrow cultures. When MoAb B1F6 was given in vivo at 1.2 mg/kg/d, ie, twice the dose used previously, dogs so treated also developed delayed marrow graft failure. Marrow failure with either MoAb involved myeloid, erythroid, and megakaryocytic lineages. Administration of recombinant canine c-kit ligand/stem cell factor (SCF) for 7 or 21 days posttransplant resulted in reversal of graft failure. Although the short course did induce a broad transient early peak of granulocytes, the longer course of SCF was accompanied by earlier sustained recovery than the short course. In conclusion, therefore, marrow graft failure induced by anti-MHC class II MoAb does not appear to be epitope dependent, involves all hematopoietic lineages, and is overcome by the administration of c-kit ligand.

Animals↗

PubMed1994

Recognition and rapid diagnosis of upper gastrointestinal cytomegalovirus infection in marrow transplant recipients. A comparison of seven virologic methods.

This is a retrospective study of 54 consecutive upper gastrointestinal endoscopies in marrow graft recipients performed to determine the incidence and distribution of CMV infection in symptomatic patients and to compare the sensitivities of 7 CMV detection techniques. At each endoscopy, 3 biopsies were obtained from the esophagus, stomach, and duodenum. Each of the 3 biopsies was assayed for CMV by different techniques. Enteric CMV was identified by one or more techniques in 52 of 486 (11%) biopsies from 14 infected patients. All patients infected with CMV initially had nausea and vomiting. In 13 of these patients, there was esophageal CMV, often associated with stomach (10 patients) and duodenal (7 patients) involvement. CMV infection of the esophagus was never identified cytologically in esophageal imprints or histologically, immunohistologically, or by DNA hybridization in esophageal epithelial cells. The most sensitive diagnostic methods were conventional and centrifugation cultures, which each identified CMV in 17 of the 30 (57%) organs positive by any technique. Indirect fluorescent antibody (IFA) staining for a late CMV antigen detected 53%, followed by in situ DNA hybridization (40%), IFA and immunoperoxidase (IP) staining for an early CMV antigen (37% and 43%), and routine histology (30%). Although no single detection technique is completely adequate for the rapid identification of CMV in small endoscopic biopsies, centrifugation culture is the method of choice, with supplementary immunohistology and in situ hybridization of archival tissue if needed.

Adult↗

PubMed1994

An evaluation of antioxidant effects on recovery from postischemic acute renal failure.

Xanthine oxidase (XO) activity and hydroxyl radical (.OH) formation are widely proposed mediators of renal reperfusion injury, potentially altering the severity of, and recovery from, postischemic acute renal failure. The goal of this study was to ascertain whether combination XO inhibitor (oxypurinol) and .OH scavenger (Na benzoate) therapy, given at the time of renal ischemia, alters the extent of: (1) tubular necrosis and filtration failure; (2) DNA fragmentation/apoptosis (assessed in situ by terminal deoxynucleotidyl transferase reactivity); (3) early tubular regenerative responses (proliferating cell nuclear antigen expression; (3H)thymidine incorporation); and (4) the rate and/or degree of functional and morphologic repair. The effects of XO inhibition, .OH scavengers, and "catalytic" iron (FeSO4) on human proximal tubular cell proliferation in vitro were also assessed with a newly established cell line (HK-2). Male Sprague-Dawley rats were subjected to 35 min of bilateral renal arterial occlusion with or without oxypurinol/benzoate therapy. These agents did not alter the extent of tubular necrosis or filtration failure, proliferating cell nuclear antigen expression or thymidine incorporation, or the rate/extent of renal functional/morphologic repair. DNA fragmentation did not precede tubular necrosis, and it was unaffected by antioxidant therapy. By 5 days postischemia, both treatment groups demonstrated regenerating epithelial fronds that protruded into the lumina. These structures contained terminal deoxynucleotidyl transferase-reactive, but morphologically intact, cells, suggesting the presence of apoptosis. Oxypurinol and .OH scavengers (benzoate; dimethylthiourea) suppressed in vitro tubular cell proliferation; conversely, catalytic Fe had a growth-stimulatory effect. These results suggest that: (1) XO inhibition/.OH scavenger therapy has no discernible net effect on postischemic acute renal failure; (2) DNA fragmentation does not precede tubular necrosis, suggesting that it is not a primary mediator of ischemic cell death; and (3) antioxidants can be antiproliferative for human tubular cells, possibly mitigating their potential beneficial effects.

Acute Kidney Injury↗

PubMed1994

An evaluation of renal tubular DNA laddering in response to oxygen deprivation and oxidant injury.

It has recently been suggested that endonuclease activation and/or apoptosis, possibly triggered by oxidant stress, are important pathogenetic mechanisms in oxygen deprivation/reoxygenation-induced proximal tubular cell death. To explore this possibility, DNA "laddering," a characteristic feature of these processes, was sought in: (1) postischemic rat kidneys (25- or 40-min arterial clamping; 0, 1, 4, 8, 24, and 48 h and 6 days reflow); (2) posthypoxic isolate rat proximal tubular segments and (3) cultured human kidney proximal tubular cells (HK-2) subjected either to energy depletion plus Ca2+ overload (antimycin A plus 2-deoxyglucose plus Ca2+ ionophore A23187), or to H2O2-induced cell death. DNA was subsequently extracted, electrophoresed through agarose gels, and visualized with ethidium bromide or Southern blotting. To maximize ladder detection, DNA samples were also end-labeled with 32P dideoxyadenosine triphosphate with terminal deoxynucleotidyl transferase (tdt), followed by electrophoresis. None of the postischemic DNA samples demonstrated any laddering by either ethidium bromide staining or Southern analysis (apoptotic lymphocyte DNA was a positive control). However, trace laddering was apparent by the tat technique, commencing at 1 h of reflow, peaking at 24 h, and resolving slowly thereafter. This finding correlated with the morphologic expression of tubular necrosis, not apoptosis. Hypoxia/reoxygenation caused proximal tubular segment death (44 to 64%), and HK-2 cells were slowly killed by both the H2O2 and the energy depletion/Ca(2+)-loading protocols. However, neither protocol induced ethidium bromide- or tdt-detectable DNA laddering. It was concluded that: (1) minimal DNA laddering develops postischemia, and this change is reliably detected only by the tdt method; (2) it correlates with the morphologic expression of tubular necrosis, not apoptosis; and (3) in vitro oxidative- and energy depletion-mediated proximal tubular cell death can be dissociated from DNA ladder formation.

Animals↗