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Biomedical subjects

D Weill

Publications and source records attributed to D Weill.

At least 19 recordsLinked to original sources
PubMed2002

Direct signal transduction via functional interferon-alphabeta receptors in CD34+ hematopoietic stem cells.

Affinity purified, freshly isolated CD34+ progenitors were shown to express low levels of type I interferon (IFN) receptors (740 +/- 60 binding sites/cell, K(d) 0.7 +/- 0.04 nM) determined by Scatchard's analysis using a radiolabelled, neutralizing, monoclonal antibody directed against the IFNAR1 chain of the human type I IFN receptor. Treatment of freshly isolated (day 0), highly purified (>95% pure) CD34+ cells with recombinant IFN-alpha resulted in rapid tyrosine phosphorylation and activation of STAT1, Tyk2 and JAK1 as shown by Western immunoblotting. Similarly, IFN treatment was shown by confocal microscopy to result in rapid nuclear localization of the transcription factors IRF1 and STAT2, demonstrating the presence of functional IFN receptors on freshly isolated (day 0) CD34+ cells. The number of specific type I IFN receptor binding sites expressed on hematopoietic progenitor cells increased to some 1440 +/- 40 per cell after 11 days of cultivation of CD34+ cells in vitrosuggesting that receptor expression increases with cell differentiation. IFN-mediated signal transduction and the inhibitory effect of IFN-alpha on 7 or 14 days CFU-GM and BFU-E colony formation was abrogated in the presence of the anti-IFNAR1 mAb, indicating that IFN-alpha acts directly on the proliferation of human hematopoietic progenitor cells via receptor activated signal transduction without excluding the induction of other cytokines or growth factors by residual accessory cells.

Active Transport, Cell Nucleus↗
PubMed2001

Management of congenital abnormalities of the donor lung.

Congenital abnormalities were encountered in three donor lungs. A donor tracheal bronchus was incorporated into the right bronchial anastomosis. Anomalous pulmonary venous return of the right upper lobe to the superior vena cava and the left upper lobe to the innominate vein were managed by bridging the anomalous veins to the left atrial cuff with autologous pericardium and donor iliac vein, respectively.

Bronchi↗
PubMed2001

Role of cytomegalovirus in cardiac allograft vasculopathy.

Cardiac allograft vasculopathy is the most common cause of death and retransplantation following heart transplantation, and about 10% of patients per year have evidence of accelerated vascular disease; 50% at 5 years. Cytomegalovirus (CMV) infection has been associated with accelerated cardiac vasculopathy and decreased 5-year survival. Prophylactic therapy using ganciclovir has reduced the incidence of CMV disease, but not in the group at highest risk, namely the seronegative recipient of an allograft from a seropositive donor (D+/R-). Combination prophylaxis consisting of CMV hyperimmune globulin (CMV-IGIV) plus ganciclovir is associated with decreased intimal thickening, reduced coronary artery disease and obliterative bronchiolitis, and improved survival.

Antiviral Agents↗
PubMed2000

The utility of open lung biopsy following lung transplantation.

BACKGROUND: Most pulmonary complications associated with lung transplantation have non-specific clinical characteristics. Furthermore, common diagnostic modalities, including bronchoscopy with transbronchial biopsy (TBB), often do not render a definitive diagnosis. In this study, we reviewed our experience with open lung biopsy (OLB) following lung transplantation, specifically regarding its ability to safely provide clinically relevant information that affects therapeutic decisions. METHODS: From October 1989 to March 2000, 202 patients underwent lung transplantation at our institution. We reviewed the clinical course of the 42 patients who received 48 OLBs. Of these patients, we determined the pre-operative clinical condition, preceding TBB histologic information, OLB histology, treatment changes, and procedural complications as a result of the OLB. RESULTS: A new, clinically unsuspected diagnosis was made in 14 biopsies (29% of all OLB), and all of these resulted in therapy changes. Thirty-two biopsies (67% of all OLB) confirmed our clinical suspicions, and new therapy was initiated in 30 of these patients. Two patients (4% of all OLB) had non-diagnostic OLB. Four biopsies (8% of all OLB), including the 2 non-diagnostic OLBs, did not result in any therapy changes or initiation of new therapy. Complications occurred in 3 patients, all of whom had an air leak for >7 days. CONCLUSION: Open lung biopsy in lung transplant patients renders a new, unsuspected diagnosis in nearly one third of patients and leads to specific, directed therapy in the vast majority of patients. Open-lung biopsy can be performed safely and should be considered when diagnosis is uncertain in clinically deteriorating patients.

Biopsy↗
PubMed2000

Adenovirus-mediated p53 gene transfer in sequence with cisplatin to tumors of patients with non-small-cell lung cancer.

PURPOSE: To determine the safety and tolerability of adenovirus-mediated p53 (Adp53) gene transfer in sequence with cisplatin when given by intratumor injection in patients with non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients with advanced NSCLC and abnormal p53 function were enrolled onto cohorts receiving escalating dose levels of Adp53 (1 x 10(6) to 1 x 10(11) plaque-forming units [PFU]). Patients were administered intravenous cisplatin 80 mg/m(2) on day 1 and study vector on day 4 for a total of up to six courses (28 days per course). Apoptosis was determined by the terminal deoxynucleotidyl- transferase-dUTP nick-end labeling assay. Evidence of vector-specific sequences were determined using reverse-transcriptase polymerase chain reaction. Vector dissemination and biodistribution was monitored using a series of assays (cytopathic effects assay, Ad5 hexon enzyme-linked immunosorbent assay, vector-specific polymerase chain reaction assay, and antibody response assay). RESULTS: Twenty-four patients (median age, 64 years) received a total of 83 intratumor injections with Adp53. The maximum dose administered was 1 x 10(11) PFU per dose. Transient fever related to Adp53 injection developed in eight of 24 patients. Seventeen patients achieved a best clinical response of stable disease, two patients achieved a partial response, four patients had progressive disease, and one patient was not assessable. A mean apoptotic index between baseline and follow-up measurements increased from 0.010 to 0.044 (P =.011). Intratumor transgene mRNA was identified in 43% of assessable patients. CONCLUSION: Intratumoral injection with Adp53 in combination with cisplatin is well tolerated, and there is evidence of clinical activity.

Adenoviruses, Human↗
PubMed2000

Adenoviral-mediated p53 gene transfer to non-small cell lung cancer through endobronchial injection.

OBJECTIVE: The objective was to determine the degree of toxicity and antitumor activity following bronchoscopic injection of an adenoviral-mediated p53 gene (Adp53) into tumors causing airway obstruction. DOSING: This was a subset analysis of a phase I dose escalation trial. SETTING: Patients were treated in the outpatient clinics at the University of Texas (MD Anderson Cancer Center, Houston, TX) and at Medical City Dallas Hospital (US Oncology, Dallas, TX). PATIENTS: Twelve patients (median age, 60 years) with advanced endobronchial non-small cell lung cancer (NSCLC) (squamous cell carcinoma, six patients; adenocarcinoma, six patients) were entered into trial. The median tumor area was 5 x 3.2 cm. All patient tumors contained a p53 gene mutation. INTERVENTIONS: Adp53 (dose range, 1 x 10(6) to 1 x 10(11) plaque-forming units) was administered by bronchoscopic intratumoral injection once every 28 days. MEASUREMENTS AND RESULTS: Toxicity attributed to the Adp53 vector was minimal. Six of the 12 patients had significant improvement in airway obstruction, and 3 patients met the criteria for partial response. CONCLUSIONS: Direct bronchoscopic injection of Adp53 into endobronchial NSCLC is safe, with acceptable levels of toxicity. The initial clinical results demonstrating relief of airway obstruction warrant further clinical investigation.

Adenoviruses, Human↗
PubMed1999

Adenovirus-mediated p53 gene transfer in advanced non-small-cell lung cancer.

BACKGROUND: Preclinical studies in animal models have demonstrated tumor regression following intratumoral administration of an adenovirus vector containing wild-type p53 complementary DNA (Ad-p53). Therefore, in a phase I clinical trial, we administered Ad-p53 to 28 patients with non-small-cell lung cancer (NSCLC) whose cancers had progressed on conventional treatments. METHODS: Patients received up to six, monthly intratumoral injections of Ad-p53 by use of computed tomography-guided percutaneous fine-needle injection (23 patients) or bronchoscopy (five patients). The doses ranged from 10(6) plaque-forming units (PFU) to 10(11) PFU. RESULTS: Polymerase chain reaction (PCR) analysis showed the presence of adenovirus vector DNA in 18 (86%) of 21 patients with evaluable posttreatment biopsy specimens; vector-specific p53 messenger RNA was detected by means of reverse transcription-PCR analysis in 12 (46%) of 26 patients. Apoptosis (programmed cell death) was demonstrated by increased terminal deoxynucleotide transferase-mediated biotin uridine triphosphate nick-end labeling (TUNEL) staining in posttreatment biopsy specimens from 11 patients. Vector-related toxicity was minimal (National Cancer Institute's Common Toxicity Criteria: grade 3 = one patient; grade 4 = no patients) in 84 courses of treatment, despite repeated injections (up to six) in 23 patients. Therapeutic activity in 25 evaluable patients included partial responses in two patients (8%) and disease stabilization (range, 2-14 months) in 16 patients (64%); the remaining seven patients (28%) exhibited disease progression. CONCLUSIONS: Repeated intratumoral injections of Ad-p53 appear to be well tolerated, result in transgene expression of wild-type p53, and seem to mediate antitumor activity in a subset of patients with advanced NSCLC.

Adenoviridae↗
PubMed1999

Acute native lung hyperinflation is not associated with poor outcomes after single lung transplant for emphysema.

BACKGROUND: Single-lung transplantation for emphysema may be complicated by acute native lung hyperinflation (ANLH) with hemodynamic and ventilatory compromise. Some groups advocate the routine use of independent lung ventilation, double-lung transplant, or right-lung transplant with or without contralateral lung volume reduction surgery in high-risk patients. The goal of this study was to determine the incidence of ANLH and identify its potential predictors. METHODS: We reviewed 51 consecutive single-lung transplants for emphysema. Symptomatic ANLH was defined as mediastinal shift and diaphragmatic flattening on chest x-ray with hemodynamic or respiratory failure requiring cardiopressor agents or independent lung ventilation. Preoperative and postoperative physiologic and hemodynamic data were analyzed from both recipients and donors. RESULTS: Sixteen patients developed radiographic ANLH; 8 were symptomatic, 2 severely so. We could not identify high-risk patients before transplant by pulmonary function tests, predicted donor total lung capacity (TLC)/actual recipient TLC ratio, pulmonary artery pressures, or the side transplanted. There was a trend toward an increased incidence of symptomatic ANLH in patients with bullous emphysema on chest computed tomography, but this was accounted for primarily by patients with alpha1-antitrypsin deficiency (4/13 vs 4/38 with chronic obstructive pulmonary disease, P = 0.10). No patient required cardiopulmonary bypass or inhaled nitric oxide intraoperatively. Patients with acute native lung hyperinflation did not have increased reperfusion edema as measured by chest x-ray score or PaO2/F(I)O2 ratio. Compared to patients without ANLH, symptomatic patients had longer ventilator times (64.9+/-14.6 hours vs 40.4+/-3.9, P = 0.02, ANOVA) and longer lengths of stay (19.3+/-2.1 days vs 13.7+/-1.3, P = 0.07), but 30-day survival was 100%. Two symptomatic patients required independent lung ventilation or inhaled nitric oxide; the others were managed with decreased minute ventilation, early extubation, and cardiopressor agents. No patient required early lung volume reduction surgery or retransplantation. Acute native lung hyperinflation had no effect on FEV1 or 6-minute walk results at 1 year; survival at 1, 2, or 3 years; or the rate of acute rejection, infection, or bronchiolitis obliterans syndrome greater than grade 2. CONCLUSION: Acute native lung hyperinflation is common radiographically but is rarely clinically severe. Although there was a trend toward an increase in symptomatic ANLH in patients with bullous emphysema, a high-risk group could not be identified preoperatively. Our results do not support the routine use of bilateral lung transplant, the exclusive use of right single-lung transplant, simultaneous lung volume reduction surgery, or independent lung ventilation for patients with emphysema. Management strategies should be employed that limit overdistension of the native lung and lead to early extubation.

Acute Disease↗
PubMed1999

Oromucosal interferon therapy: pharmacokinetics and pharmacodynamics.

Oromucosal administration of [125I]-labeled recombinant human interferon-alpha1-8 (IFN-alpha1-8), which is biologically active in the mouse, resulted in readily detectable levels of radioactivity in the serum of animals within 5 min. Biologically active IFN could not be detected in the serum at any time after oromucosal administration, however, and SDS-PAGE analysis showed that the material present in the serum was of low molecular weight and most probably reflected absorption of degradation products following digestion of IFN in the stomach and small intestine. Furthermore, oromucosal administration of murine IFN-alpha/beta (MuIFN-alpha/beta) had no significant effect on the expression of IFN-responsive genes in either peripheral blood mononuclear cells or splenic lymphocytes even though in the same animals IFN treatment activated gene transcription locally in the lymphoid tissue of the oropharyngeal cavity and caused a marked systemic antiviral activity. Oromucosal administration of MuIFN-alpha/beta had no significant effect on either the number of circulating peripheral blood leukocytes or the number of granulocyte-macrophage colonies recovered from the bone marrow of IFN-treated animals. These results suggest that the mechanism of action of oromucosal IFN therapy is distinct from that of parenterally administered IFN and may involve, in the abundant lymphoid or epithelial tissue of the oropharyngeal cavity, either production of a soluble factor or activation of a specific cell population that enters the circulation to mediate the elimination of virus-infected or neoplastic cells.

2',5'-Oligoadenylate Synthetase↗
PubMed1998

Pulmonary capillaritis: a possible histologic form of acute pulmonary allograft rejection.

Acute rejection after lung transplantation occurs commonly and is usually characterized histologically by a perivascular mononuclear infiltrate. We report five cases of pulmonary capillaritis with a histologic appearance distinct from typical rejection, occurring in patients ranging in age from 18 to 45 years, with a variety of underlying diseases including alpha1 antitrypsin deficiency, pulmonary hypertension, cystic fibrosis, and rheumatoid arthritis. Four of the five patients had alveolar hemorrhage histologically, and two had frank hemoptysis. Time of onset ranged from 3 weeks to many months after transplantation. Three cases were fulminant, and there were two deaths. In only one case, with methicillin-resistant Staphylococcus aureus bronchitis, could infection be established. All were treated with intensification of immunosuppressive therapy. Plasmapheresis was carried out in two cases and coincided with temporary improvement, but its efficacy was questionable because of concurrent immunosuppressive therapy. Two had recurrent biopsy-proven acute rejection within 6 weeks of treatment, and one had recurrent severe pulmonary hemorrhage that abated with total lymphoid irradiation. Our experience suggests that pulmonary capillaritis in lung transplant recipients can be an acute, fatal illness with the potential for recurrence in the survivors. We speculate that it represents a form of acute vascular rejection. Early pathologic diagnosis and aggressive immunosuppressive therapy are recommended. Although a humoral component was not documented, the possible response to plasmapheresis requires continued evaluation.

Acute Disease↗
PubMed1998

Adverse effects of medications commonly administered to thoracic surgical patients.

A wide variety of medications is commonly used following thoracic surgical procedures. All of these medications have associated side effects that may adversely affect the recovery of patients. A complete understanding of the important adverse effects of all the medications used postoperatively can limit or eliminate unwanted medication effects and lead to a more successful outcome. This article will review the important actions and side effects of the most commonly administered medications following thoracic surgical procedures.

Analgesics, Opioid↗
PubMed1997

XO increases neutrophil adherence to endothelial cells by a dual ICAM-1 and P-selectin-mediated mechanism.

Circulating xanthine oxidase (XO) can modify adhesive interactions between neutrophils and the vascular endothelium, although the mechanism underlying this effect are not clear. We found that treatment with XO of bovine pulmonary artery endothelial cells (EC), but not neutrophils or plasma, increased adherence, suggesting that XO had its primary effect on EC. The mechanism by which XO increased neutrophil adherence to EC involved binding of XO to EC and production of H2O2. XO also increased platelet-activating factor production by EC by a H2O2-dependent mechanism. Similarly, the platelet-activating factor-receptor antagonist WEB-2086 completely blocked XO-mediated neutrophil EC adherence. In addition, neutrophil adherence was dependent on the beta 2-integrin Mac-1 (CD11b/CD18) but not on leukocyte functional antigen-1 (CD11a/CD18). Treatment of EC with XO for 30 min did not alter intercellular adhesion molecule-1 surface expression but increased expression of P-selectin and release of von Willibrand factor. Antibodies against P-selectin (CD62) did not affect XO-mediated neutrophil adherence under static conditions but decreased both rolling and firm adhesive interactions under conditions of shear. We conclude that extracellular XO associates with the endothelium and promotes neutrophil-endothelial cell interactions through dual intercellular adhesion molecule-1 and P-selectin ligation, by a mechanism that involves platelet-activating factor and H2O2 as intermediates.

Animals↗
PubMed1996

Colon perforation after lung transplantation.

BACKGROUND: Colon perforation has been previously described after solid organ transplantation. Since the inception of the lung transplant program at the University of Colorado 60 isolated lung transplantations have been performed. Four of these patients have suffered spontaneous colonic perforation. METHODS: The case history of each lung transplant patient with a colon perforation and the literature were reviewed. RESULTS: An increased incidence of colon perforation in lung transplant patients was identified. Diverticulitis was found to be the predominant cause, and an association with steroids was noted. The two deaths in this series were in patients receiving high-dose steroids in whom invasive Aspergillus infections developed. CONCLUSIONS: Careful screening of the gastrointestinal tract before transplantation is advocated. A steroid-sparing immunosuppressive regimen is recommended. All lung transplant patients with abdominal complaints require an aggressive work-up, and surgeons should have a low threshold for laparotomy. Conservative surgical principles, including resection of the perforated segment of colon and proximal end-colostomy rather than primary anastomosis, are necessary for the optimal outcome.

Adult↗
PubMed1996

Blood monocyte activation in rheumatoid arthritis: increased monocyte adhesiveness, integrin expression, and cytokine release.

Infiltration of the synovium by mononuclear cells, namely lymphocytes and monocytes, is one of the main features of rheumatoid arthritis (RA) and is considered to be responsible for the development of the disease. In this study in 31 consecutive patients with RA, we investigated whether peripheral blood monocytes exhibited markers of cellular activation related to cell migration. Using flow cytometry with the respective specific antibodies, we studied the expression of integrins CD11a, CD11b, CD11c, CD49d (VLA-4), and CD49e (VLA-5) on monocytes from patients with RA and from normal (N) subjects. IL-1 beta, IL-6, and tumour necrosis factor-alpha (TNF-alpha) production by cultured monocytes was measured by immunoassay. Adhesiveness of monocytes was studied on various surfaces (plastic, human fibronectin, gelatin-coated plasma, subendothelial matrix) and on cultured endothelial cells under basal conditions or after stimulation by IL-1 beta. An increased number of CD14+ monocytes (Mo) from RA patients expressed the CD11b molecule (RA Mo = 90.3%, N Mo = 83.4%, P < 0.005). The expression of CD11b on CD14+ monocytes was significantly increased in RA patients (median fluorescence intensity (FI): RA Mo = 145 (range 80-466) units; normal Mo = 95 (range 24-164) units; P < 0.003). Production of extracellular IL-1 beta and IL-6 by RA monocytes was significantly enhanced compared with monocytes from normal subjects (IL-1 beta: RA = 2.65 +/- 0.91 ng/ml versus N = 1.35 +/- 0.85 pg/ml, P < 0.05; IL-6: RA = 4.83 +/- 0.90 ng/ml versus N = 2.40 +/- 0.95 ng/ml, P < 0.05). Compared with normal monocytes, RA monocytes exhibited increased adhesion to the various surfaces studied (plastic, P < 0.01; fibronectin, P < 0.01; and gelatin-coated normal or RA plasma, P < 0.01) as well as to unstimulated (P < 0.01) and IL-1 beta-stimulated endothelial cells (IL-1 beta for 4 h, P < 0.05; IL-1 beta for 24h, P < 0.05). In our study, blood monocytes from RA patients exhibited features of activation related to cell adhesion.

Arthritis, Rheumatoid↗
PubMed1996

Induction of tumor necrosis factor alpha expression in human T lymphocytes following ionizing gamma irradiation.

In this work, we present evidence that enriched human peripheral blood T lymphocytes, depleted of contaminating monocytes, rapidly express tumor necrosis factor alpha (TNF-alpha) mRNA when exposed to low doses of gamma-irradiation. In total PBL, TNF-alpha mRNA accumulation increased threefold as early as 30 minutes following exposure to 4 Gy and then declined to the baseline level by 3-5 h, as measured by the reverse transcriptase-polymerase chain reaction (RT-PCR). The increase in TNF-alpha mRNA was also observed in populations of enriched T cells and decreased when the dose of irradiation was increased to 10 Gy, strongly suggesting that T lymphocytes, the most radiosensitive cells of the body, contributed directly to the increase of TNF-alpha mRNA. A good correlation was found between mRNA expression and TNF-alpha protein secretion. Interestingly, a eightfold increase in glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA accumulation was also detected in both PBL and enriched T cells irradiated at 4 Gy for 3 h compared with unirradiated cells. This irradiation effect was almost completely abolished, however, following exposure to 10 Gy. Together these data suggest that T cells are responsible for the irradiation-induced expression of TNF-alpha and GAPDH.

Base Sequence↗