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Biomedical subjects

A Elias

Publications and source records attributed to A Elias.

At least 91 records · Page 5Linked to original sources
PubMed1991

[Venous Doppler echography in acute pulmonary embolism].

In patients with clinically suspected pulmonary embolism, the signs and symptoms of venous thrombosis are late, insensitive and non specific. Detection of vein thrombosis requires more objective tests: (1) anatomical such as phlebography and ultrasonography which directly visualize the thrombus; the latter has the advantage of being non invasive and of providing a means to study extravascular structures as well as functional information, especially when combined with doppler velocimetry; (2) haemodynamic tests such as doppler and plethysmography which show impairment on venous return. These indirect tests are less reliable for detecting non occlusive and distal thrombi and are less specific than phlebography. Compared with phlebography, ultrasonic duplex scanning is very reliable and competitive for diagnosis and exact localization of the thrombosis, irrespective of its site (distal or proximal), its extent (isolated or extensive) and the degree of obstruction (partial or complete). However to be fully efficient, this technique must be performed by a trained specialist using specific equipment; it must always include doppler examination and explore the entire venous network. In addition, this technique makes it possible to explore the inferior and superior caval systems and the cardiac structures on the path of the migrating thrombus. Like phlebography, ultrasonography indicates venous thromboembolism only when it is positive; negative results do not exclude the diagnosis.

Acute Disease↗
PubMed1991

[Role of Doppler echography in the diagnosis of venous thrombosis].

The diagnosis of deep vein thrombosis (DVT) by non-invasive techniques is usually based on the haemodynamic changes detected by doppler ultrasound and plethysmography. These two investigations are not very sensitive in the diagnosis of non-occlusive proximal thrombosis or distal (infrapopliteal) and isolated thromboses. Ultrasonic Duplex Scanning (B mode and Doppler) is a new method of investigation of DVT which visualises the anatomy of the veins and surrounding structures and also provides assessments of the venous circulation. The diagnosis of DVT is made on the finding of an abnormal endoluminal image, the absence of venous compressibility and doppler changes. Duplex ultrasonography differentiates DVT from extrinsic compression, enables diagnosis of even nonocclusive or isolated proximal thrombosis irrespective of its site and of distal thrombis. The site, extension and age of the thrombosis may also be estimated. It is very competitive with phlebography and is even superior in some indications. This method has been evaluated mainly in patients with clinically suspected DVT. The mean values of diagnostic sensitivity and specificity compared with phlebography are over 95% in the examination of popliteal and femoral veins; iliac veins, inferior vena cava and calf veins have correctly rarely been studied but with good results: the sensitivity of diagnosis of distal DVT is approximately 90%. Duplex ultrasonography is a non-invasive, cost-effective and reliable method which is widely used, though requiring further validation both in the diagnosis of symptomatic and asymptomatic DVT and its surveillance. The diagnostic value of the investigation is operator dependent and is also influenced by the equipment and protocol of examination. The value of color flow imaging has not yet been well established.

Humans↗
PubMed1991

Using comparative clinical information to understand practice patterns and affect organizational change.

The University Hospital Consortium is collecting clinical, administrative and financial data from its members to develop a Clinical Information Network. The value of this collective data lies in how comparative information about peer hospitals and physicians in the same specialty can be used to influence practice. The raw data from each hospital is analyzed, classified, normalized and stored in a data repository which is easily accessible. This data becomes information when it is presented in a variety of ways, and is supported by a knowledge-base of health care rules. The "drilling down" technique to progressive levels of detail serves the needs of all levels in the organization--executives, managers, and analysts. The system combines the power of a mainframe for the data repository with the ease of use of a PC-based workstation. With an open-ended approach, the users can ask a variety of questions of the data, as well as perform statistical analysis, create graphical presentations and generate explanations of the analysis techniques.

Artificial Intelligence↗
PubMed1990

Relationship of bcr breakpoint to chronic phase duration, survival, and blast crisis lineage in chronic myelogenous leukemia patients presenting in early chronic phase.

Strong evidence implicates fusion of control elements and 5' sequences of the bcr gene of chromosome 22 with 3' sequences of the c-abl gene of chromosome 9 in the pathogenesis of Ph-positive and certain cases of Ph-negative chronic myelogenous leukemia (CML). Since this fusion gene gives rise to a chimeric tyrosine protein kinase with transforming potential, and since the bcr exon contribution to this chimeric protein is variable, the question has arisen as to whether bcr breakpoint location and bcr exon contribution could influence the clinical course of CML. Prior studies have yielded conflicting results on this point. Here we have looked, in a manner approximating a prospective analysis, at the relation of bcr breakpoint localization to the duration of chronic phase, total survival, and blast crisis phenotype in 81 patients presenting in the chronic phase of CML. We have found no significant differences in chronic phase duration or total survival among patients with breakpoints in the three major subregions of a breakpoint cluster region within the bcr gene. These findings indicate that chronic phase duration and total survival cannot be predicted from bcr breakpoint for CML patients presenting in chronic phase and suggest that unknown oncogenic events determining the onset of blast crisis are the prime determinants of prognosis. Combined analysis of blast crisis cell lineage in our patients and patients presented in a previous study has revealed an overall ratio of myeloid:lymphoid (M:L) crisis of 3.4:1, but a striking predominance of myeloid crisis in patients with breakpoints in subregion 2 (M:L of 9:1), and a lower than expected M:L ratio (1.6:1) among patients with breakpoints in subregion 3 (P for subregion 2 versus 3 = .012; subregions 0,1,2 versus 3 = .012; subregions 0,1,3 versus 2 = .032). The molecular basis for this divergence from the anticipated M:L ratio in patients with breakpoints in bcr subregions 2 and 3 is unknown.

Adult↗
PubMed1990

An adherent subline of a unique small-cell lung cancer cell line downregulates antigens of the neural cell adhesion molecule.

Small-cell lung cancer (SCLC) lines are distinguished from non-small-cell lung cancer (NSCLC) lines by their growth in floating aggregates, in contrast to the adherent monolayers formed by NSCLC cells in culture. Of 50 well-characterized SCLC lines recently described by the National Cancer Institute (NCI)-Navy Medical Oncology Branch, only four variant cell lines (SCLC-v) grew as adherent monolayers. One line, NCI-H446, was unique in growing long-term with coexisting floating and surface adherent subpopulations. We have physically segregated these two populations over many passages in vitro to enrich for relatively pure cultures of floating and adherent cells. No differences in c-myc expression, keratin pattern, or cytogenetic appearance were found between the adherent and floating sublines. However, expression of the neuroendocrine marker neuron-specific enolase in the floating cells was three times that found in the adherent cells. The floating subline also had much greater surface expression of neuroendocrine tumor antigens detected by monoclonal antibodies UJ13A and HNK-1, which have been recently shown to detect the neural cell adhesion molecule (NCAM) on SCLC cells. Two other adherent SCLC-v lines were also found to be unreactive with UJ13A and HNK-1, generalizing the association between NCAM expression and the growth of most SCLC cultures as floating aggregates. In conclusion, we have an interesting model to study expression of NCAM as related to the adhesive properties of SCLC cells.

Antibodies, Monoclonal↗
PubMed1990

Hepatic venoocclusive disease in autologous bone marrow transplantation of solid tumors and lymphomas.

Retrospective review of 291 solid tumor and lymphoma patients undergoing autologous bone marrow transplantation (BMT) was performed to determine the influence of pretransplant characteristics and preparative regimen to the development of hepatic venoocclusive disease (VOD). Twelve patients (4.1%) developed a clinical syndrome of right upper quadrant (RUQ) tenderness or hepatomegaly, jaundice, and ascites, with or without encephalopathy, within 40 days of marrow reinfusion. Evidence of metastatic liver disease was the only pretransplant characteristic predictive for VOD (P = .0002). Sex, age, histology, hepatitis B serology, and elevated liver function tests were not predictive. No individual preparative agent had a significant effect on the development of VOD. However, a single 2-hour infusion of carmustine (BCNU) (greater than or equal to 450 mg/m2) led to an increased incidence of VOD when compared with the same dose administered in a fractionated schedule (P = .0258) when given with two other chemotherapeutic agents. Seven of eight autopsy specimens confirmed the clinical diagnosis of VOD. The four patients in whom clinical VOD resolved had lower median peak bilirubins (7.3 v 15.9 mg/dL), lower median peak creatinines (2.1 v 4.1 mg/dL), and relatively quick engraftment of neutrophils (mean, 18.7 days). One of the four patients in whom VOD resolved had other grade 4 (life-threatening) toxicities in contrast to eight of eight who succumbed. In summary, VOD is an uncommon complication in autotransplantation of solid tumors and lymphomas. Our data suggest caution in selecting patients with known metastatic liver disease and consideration of a fractionated BCNU schedule especially in combination with other alkylating agents.

Adult↗
PubMed1990

A phase I-II study of cyclophosphamide, thiotepa, and carboplatin with autologous bone marrow transplantation in solid tumor patients.

The principles of dose-response and combination chemotherapy were basic to the design of the initial curative standard-dose treatment regimens for leukemias, lymphomas, and testis cancer. Agents were selected with different dose-limiting toxicities, resulting in subadditive toxicity in combination. A fourth principle in the design of curative regimens was to combine agents with different mechanisms of action to avoid cross-resistance. Based on these principles, combinations of the highest tolerated doses of active noncross-resistant agents are required to decrease the emergence of drug resistance and achieve optimum cytotoxicity. Hematopoietic stem-cell support provides a mechanism for significantly increasing the doses of active agents, a strategy that has resulted in the cure of 10% to 50% of selected patients with lymphoma who could not be cured with standard-dose therapy. The lack of sufficiently effective cytoreductive conditioning regimens remains the major impediment to improving the high-dose therapy of patients with solid tumors. In this study, 27 patients with solid tumors were treated with a combination of cyclophosphamide, thiotepa, and carboplatin (CTCb) in a phase I-II study. Severe mucositis and neurotoxicity were dose-limiting. The maximum-tolerated dose (MTD) of the combination was 6.0 g/m2 of cyclophosphamide, 500 mg/m2 of thiotepa, and 800 mg/m2 of carboplatin. There were two deaths (7%) of sepsis, and an overall response rate of 72% in refractory tumors (81% in breast cancer). CTCb is a combination with low morbidity and high cytoreductive efficacy designed to exploit the principles of curative cancer chemotherapy.

Adult↗
PubMed1990

Dana-Farber Cancer Institute studies in advanced sarcoma.

In a phase II trial of ifosfamide 2 g/m2 days 1 to 4 with mesna uroprotection in 124 patients who had previously failed treatment for sarcomas, 3% achieved a complete response (CR), and 18% had a CR or partial response (PR). In the subset of patients with soft-tissue sarcomas, the response rate for the 64 patients who received bolus administration was 26% compared with 9% for the 60 patients who received a continuous infusion (Cl) schedule (P = .03). When mesna was unavailable, the incidence of hematuria was significant in patients, with three of four patients affected. Microscopic hematuria was uncommon in patients receiving mesna. Hematuria in the group as a whole was not associated with prior treatment with cyclophosphamide, pelvic radiotherapy, age, or a bolus versus Cl schedule. Thus, this and other studies confirm that ifosfamide is active in failed sarcomas. In sequential phase I/II trials, 111 patients who were previously untreated for metastatic or inoperable sarcomas received doxorubicin, ifosfamide, dacarbazine at doses of 60, 7,500, and 900 mg/m2, respectively, by Cl over 72 hours; myelosuppression was dose-limiting. Eleven patients (10%) achieved CRs, with an overall response rate of 47%. Most responses (approximately 70%) were observed within two cycles, and median times to progression were 10 and 9 months for CR and PR, respectively. Following CR, two patients remained disease-free at 32 and 16 months. Of 15 additional patients rendered disease-free with surgery following at least a minor response to chemotherapy, two remained disease-free at 30 and 18 months with no further therapy. Central nervous system (CNS) metastases developed in 11 patients, all of whom had high-grade sarcomas; seven of these patients were still responding systemically (three CRs). This regimen is undergoing evaluation in a randomized trial versus doxorubicin and dacarbazine alone in untreated advanced sarcoma and is being compared with observation in the adjuvant treatment of high-grade sarcomas.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1990

High-dose thiotepa alone and in combination regimens with bone marrow support.

Curative treatment regimens for leukemias, lymphomas, and testicular cancer have been based on laboratory observations of a clear relationship (generally linear-log) between increasing doses of chemotherapeutic agents and tumor cytotoxicity and on recognition of the need for combination chemotherapy to avoid the emergence of drug resistance. Chemotherapeutic agents have been selected for combinations based on cytotoxic activity, different mechanisms of action (to avoid cross-resistance), and different dose-limiting toxicities (to avoid additive toxicity). The ideal combinations use the highest tolerable doses of active non-cross-resistant agents to minimize the potential for drug resistance and achieve optimum cytotoxicity. Dose escalation is often limited by myelosuppression. Hematologic stem cell support from bone marrow or peripheral blood allows the administration of significantly higher doses of chemotherapy. In 1977, Thomas and colleagues in Seattle reported that 13 of 100 patients who underwent bone marrow transplantation for relapsed acute leukemia were disease-free 1 to 4.5 years later. Today, almost 50% of selected patients with acute myelogenous leukemia who undergo transplantation with human leukocyte antigen-matched sibling donor marrow during first remission are cured. Between 20% and 50% of lymphoma patients who undergo transplantation after failing conventional treatment have survived; those whose disease is responding to standard-dose therapy at the time of transplant have the best prognosis. Conditioning regimens that are sufficiently cytoreductive are not currently available for patients with solid tumors. The diversity of solid tumors makes it likely that a variety of regimens will be required. In a sequence of laboratory and clinical studies, we have constructed and evaluated a regimen comprising 6 g/m2 of cyclophosphamide, 500 mg/m2 of N,N',N''-triethylenethiophosphoramide (thiotepa), and 800 mg/m2 of carboplatin. The response rate in women with measurable breast cancer was 81%. While profound myelosuppression was noted, organ toxicity has been rare. This regimen, designed to exploit the principles of curative cancer chemotherapy, is associated with low morbidity and high cytoreductive efficacy. The regimen is currently being evaluated in a phase II trial in patients with previously untreated metastatic breast cancer who are responsive to conventional-dose chemotherapy. Of 29 patients entered in the study, only one has died of toxicity, confirming the low incidence of treatment-related toxicity associated with the regimen.

Adult↗
PubMed1990

Mesna, doxorubicin, ifosfamide, dacarbazine (MAID) regimen for adults with advanced sarcoma.

The mesna, doxorubicin, ifosfamide, dacarbazine regimen produced a 47% response rate (including 10% complete responses) in 105 eligible adults with advanced sarcoma. The major dose-limiting toxicity was granulocytopenia. There was one toxic death from sepsis. Central nervous system and renal toxicity occurred infrequently, perhaps as a result of the continuous-infusion schedule. This regimen is being evaluated further in advanced disease, the adjuvant setting, and in combination with bone marrow colony-stimulating factors.

Adult↗
PubMed1990

Ifosfamide and mesna: response and toxicity at standard- and high-dose schedules.

In two sequential trials, 154 patients were treated with dosages of ifosfamide, ranging between 8 and 18 g/m2 divided over 4 days, with mesna uroprotection. The first was a phase II efficacy trial in 125 advanced sarcoma patients (Antman et al: J Clin Oncol 7:126-131, 1989), while the second was a dose escalation trial involving 29 patients (Elias et al: J Clin Oncol 8:170-178, 1990). In the first trial, patients received 8 to 10 g/m2 ifosfamide either by bolus or continuous infusion. The response rate for the 64 patients receiving bolus administration was 23% compared with 12% for the 60 patients receiving a continuous infusion schedule (P = .09). Of the 154 patients, 144 had sarcoma and had failed at least one previous regimen. Of these 144, 4% responded completely and 23% had a complete or partial response. The maximum tolerated dose of ifosfamide was 16 g/m2 in the second trial. Dose-limiting renal toxicity was observed at 18 g/m2 ifosfamide (Elias et al: J Clin Oncol 8:170-178, 1990). The duration of myelosuppression and the frequency and severity of mucositis and renal tubular acidosis were dose-dependent. A median of 11 days (range, 8 to 18) of granulocytopenia (less than 500/microL) were observed. Thus, autologous bone marrow reinfusion was not required. Severe central nervous system toxicity (transient confusion, hallucinations, and somnolence) was observed sporadically at both low- and high-dose levels. The first four patients on the standard-dose study did not receive mesna because it was unavailable; three developed gross hematuria. In patients who received mesna, hematuria was uncommon. Hematuria in the group as a whole was significantly associated with a lack of uroprotection, but was not associated with prior cyclophosphamide, pelvic radiotherapy, age, or bolus versus a continuous infusion schedule. Patients receiving ifosfamide with mesna uroprotection can tolerate considerable dose escalation over the usual prescribed doses before nonhematologic toxicity becomes dose-limiting. Ifosfamide, with its broad activity in solid tumors, may prove to be an important addition to high-dose combination-chemotherapy regimens (Elias et al: J Clin Oncol 8:170-178, 1990).

Adolescent↗
PubMed1989

Enhancement of superoxide anion release by granulocytes harvested from patients receiving granulocyte-macrophage colony-stimulating factor.

We examined the rate and quantity of superoxide anion (O2-) generation by granulocytes harvested from the blood of patients before and after a 12-24 h constant intravenous infusion with recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSFrh). Seven previously untreated patients with sarcomas who exhibited no bone marrow involvement by their disease were studied. Granulocytes were harvested from the peripheral blood of each patient before and after intravenous infusion with GM-CSFrh. The total quantity of O2- produced and the kinetics of its release were then determined following in vitro activation of the cells by the chemotactic peptide N-formyl methionyl-leucylphenylalanine (fMLP) or by phorbol myristate acetate (PMA). In all cases, the amount of O2- generated and the rate of its release were significantly increased after GM-CSFrh infusion. Our findings indicate that intravenous administration of GM-CSFrh to patients heightens the functional responsiveness of circulating granulocytes.

Adult↗
PubMed1989

Response to ifosfamide and mesna: 124 previously treated patients with metastatic or unresectable sarcoma.

European and American investigators have reported response rates of 38% to 83% for ifosfamide alone in pretreated sarcomas. In a phase II trial of ifosfamide 2.0g/m2 days 1 to 4 with mesna uroprotection in 124 patients with previously failed sarcomas, four (3%) responded completely (95% exact confidence interval, 1% to 8%) and 26 (21%) had a complete or partial response (95% exact confidence interval, 14% to 29%). The median time to progression was 5 and 9 months for partial and complete responders, respectively. In the subset of soft tissue sarcomas, the response rate for the patients receiving bolus administration was 26%, compared with 9% for the patients receiving a continuous infusion schedule (P = .03). The response rates among patients with soft tissue and bony sarcomas with a performance score of 0-2 and 0-1 prior to chemotherapy administration were 20% and 40%, respectively. Somnolence or confusion developed in 19%. Neurotoxicity was significantly associated with poor performance status (P less than .01), elevated creatinine (P less than .01), and low bicarbonate levels (P = .05). A serum bicarbonate less than 20 developed in 31% of the patients and was significantly associated with older age (P = .01), elevated creatinine (P = .02), and female sex (P = .06). Hematuria was significantly associated with no uroprotection (the first four patients did not receive mesna because it was unavailable), but was not associated with prior cyclophosphamide, pelvic radiotherapy, age, or bolus v continuation infusion schedule. Thus, ifosfamide is active in failed sarcomas and warrants further study in previously untreated patients with sarcoma.

Adolescent↗
PubMed1989

A phase I clinical and pharmacokinetic study of carboplatin and autologous bone marrow support.

A series of 33 patients were treated with a four-day continuous infusion of carboplatin in a phase I study to determine the maximum-tolerated dose (MTD) of this agent when used with autologous bone marrow reinfusion. Doses were escalated from 375 to 2,400 mg/m2; autologous bone marrow reinfusion was added to the regimen at doses of 1,600 mg/m2 and above. The MTD was determined to be 2,000 mg/m2. Dose-limiting toxicity consisting of reversible hepatotoxicity, renal dysfunction, and moderate to severe ototoxicity was observed with a dose of 2,400 mg/m2. There were ten responses in 31 heavily pretreated patients, including six responses in 11 patients with recurrent ovarian cancer. Pharmacokinetic studies revealed a systemic clearance (Clss) of 4.5 L/m2/h. This value is consistent with clearances reported for carboplatin administered at lower doses and by different schedules. No evidence for saturation of systemic clearance at higher doses was observed. Carboplatin appears to be an active drug that can undergo considerable dose escalation when used in conjunction with autologous bone marrow support.

Adult↗
PubMed1989

Response to mesna, doxorubicin, ifosfamide, and dacarbazine in 108 patients with metastatic or unresectable sarcoma and no prior chemotherapy.

In this phase II trial, 105 eligible patients with no prior chemotherapy and advanced sarcoma received doxorubicin, ifosfamide, and dacarbazine (DTIC) with mesna uroprotection (MAID). Starting doses of these drugs were 60, 7,500, and 900 mg/m2 divided over 72 hours by continuous infusion, respectively. Mesna was given for 84 to 96 hours at 2,500 mg/m2/d. Myelosuppression was dose limiting, causing the only toxic death (sepsis). Nonhematologic toxicity consisted predominantly of anorexia and vomiting. Severe mucositis, macroscopic hematuria, renal tubular acidosis, renal failure, and CNS toxicity occurred in less than 5% of cycles. No cardiotoxicity was detected. The overall response rate (10% complete response [CR]) was 47% (95% confidence intervals, 5% to 18% and 37% to 57%, respectively). Most responses (approximately 70%) were observed within two cycles. Median times to progression were 10 and 9 months, respectively. Histologic high tumor grade, lesions less than 5 cm, and less than 1 year from diagnosis to study entry correlated with the probability of response. The median survival was 16 months. Time from diagnosis to study entry, performance status, and extent of disease, but not histologic grade, correlated with survival. Following CR, two patients remain disease-free at 32 and 16 months. Of the 15 additional patients rendered disease-free with surgery, two remain disease-free at 30 and 18 months with no further therapy. While most relapses occurred in sites of prior involvement, death from CNS metastases occurred in 11 of the 80 patients with high-grade sarcomas, of whom seven were still responding systematically (three complete responders). Because of its substantial response in this phase II trial, the MAID regimen is being compared with doxorubicin and DTIC alone in advanced sarcomas and to observation in the adjuvant treatment of high-grade sarcomas in randomized trials.

Actuarial Analysis↗
PubMed1989

Speech therapy for psychogenic voice disorder: a survey of current practice and training.

A survey of speech therapists in the United Kingdom showed that they usually undertook the treatment of psychogenic voice disorders. Their pre-qualification education had provided advice that was usually reflected accurately in the experience they gained in practice, though during their education about a third had lacked any opportunity to treat or observe psychogenic voice disorders. The appropriate duration of treatment appears to be in doubt. At present, speech therapists acquire many of the psychological skills required for treatment after qualification. There is a substantial need for post-qualification courses, although more practical instruction on psychological treatment might advantageously be incorporated in initial education.

Humans↗