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D Shure

Publications and source records attributed to D Shure.

At least 19 recordsLinked to original sources
PubMed1992

PDGF AA homodimers are potent chemoattractants for fibroblasts and neutrophils, and for monocytes activated by lymphocytes or cytokines.

The A-chain homodimers of the platelet-derived growth factor (PDGF AA) are widely expressed in normal and transformed cells. The mitogenic properties of PDGF AA are well established; however, the chemotactic potential of PDGF AA remains controversial. We now show that PDGF AA is a strong chemoattractant for human monocytes, granulocytes, and fetal bovine ligament fibroblasts. However, highly purified (greater than 98%) monocytes require the addition of lymphocytes or IL-1 for chemotactic responsiveness to PDGF AA but not for full chemotactic activity with formyl-methionyl-leucyl-phenylalanine (fMLP) or C5a. These results indicate that PDGF AA is a potent chemoattractant. These results also indicate that monocytes require activation either by lymphocytes or exogenous cytokines in order to respond chemotactically to PDGF AA but not to fMLP or C5a and suggest roles of the lymphocyte and cytokine in the chemotactic response of the monocyte to PDGF AA in vivo.

Animals↗
PubMed1991

Radiographically occult endobronchial obstruction in bronchogenic carcinoma.

PURPOSE: While central endobronchial tumors may become radiographically detectable when they cause significant endobronchial obstruction, the incidence of radiographically undetectable obstruction is not known. This study prospectively examined the incidence of radiographically undetectable completely obstructing lesions encountered during routine diagnostic bronchoscopy. PATIENTS AND METHODS: Patients referred for bronchoscopy at the San Diego Veterans Administration Medical Center because of suspected bronchogenic carcinoma formed the population base. Chest radiographs were interpreted routinely 24 hours prior to bronchoscopy. Patients found to have complete endobronchial obstruction during bronchoscopy were included in the analysis. RESULTS: Eighty-one completely obstructing lesions were found in 77 patients. No radiographic signs of obstruction were found in 36 (44%) completely obstructing endobronchial lesions. There was no difference in the rate of radiographically occult tumors based on cell type. Obstruction of segmental bronchi was more likely to be undetectable than obstruction of more proximal airways. Chest radiographs were normal in 13 (16%). All 13 had risk factors for and symptoms suggestive of bronchogenic carcinoma. CONCLUSION: Complete endobronchial obstruction due to bronchogenic carcinoma can occur frequently in patients at risk for lung cancer. The significant incidence of radiographically undetectable complete obstruction has implications for the diagnosis, staging, and assessment of treatment of lung cancer.

Adenocarcinoma↗
PubMed1991

Endobronchial suture. A foreign body causing chronic cough.

Although rarely considered in series of lower airway foreign bodies, endobronchial sutures can cause chronic cough or hemoptysis years after thoracic surgery. Eight endobronchial sutures were found in six patients who had undergone surgery four to 30 years prior to admission. Symptoms began two to 25 years after surgery and lasted from two to six years prior to diagnosis. Cough had been attributed to chronic bronchitis or bronchiectasis in five patients and to tracheal narrowing secondary to surgical repair of tracheomalacia in the sixth. Bronchoscopy was diagnostic in all cases. Suture removal was performed with either forceps or endoscopic suture scissors to cut the suture followed by extraction with forceps. Symptoms resolved within three days and granulation tissue by two to four weeks after suture removal. This series suggests that endobronchial suture should be considered in patients with a history (even remote) of previous thoracic surgery who present with chronic, persistent cough unresponsive to specific therapy for any underlying pulmonary disease.

Aged↗
PubMed1989

Transbronchial biopsy and needle aspiration.

Transbronchial biopsy and transbronchial needle aspiration greatly increase the utility of bronchoscopy in the diagnosis of a variety of disease processes. Transbronchial needle aspiration has brought into focus the importance of good cytopathologic support. The addition of histologic specimens (for light and electron microscopy) with the newer large-bore needles may further increase the utility of transbronchial needle aspiration. Both techniques are limited, in part, by the lack of distal tip deflection of the sampling instrument for steering accurately to peripheral masses. Tip deflection may have been partly responsible for the good yields reported for the double-hinged curet on small nodules, although the bronchographic map was also a factor. A steerable brush was described several years ago, but it was somewhat difficult to accurately maneuver, and long-term results were never reported. As yet, no easy answer is available for this problem. In the future, new generations of ultrathin bronchoscopes may permit much more accurate placement of sampling devices in the periphery of the lung and will represent an exciting diagnostic advance.

Biopsy, Needle↗
PubMed1988

Pulmonary edema due to upper airway obstruction in adults.

A report of pulmonary edema following acute upper airway obstruction in an adult is presented, and the literature involving 25 additional cases is reviewed. This form of pulmonary edema appears to be related to markedly negative intrathoracic pressure due to forced inspiration against a closed upper airway resulting in transudation of fluid from pulmonary capillaries to the interstitium. Postanesthetic laryngospasm is the most common cause of pulmonary edema in adults (11/26 cases). The edema usually clears rapidly with supportive care. Aggressive diagnostic and therapeutic interventions may be avoided if the syndrome is recognized. Maintenance of oxygenation and a patent airway are the mainstays of treatment.

Adult↗
PubMed1987

Thromboendarterectomy for chronic, major-vessel thromboembolic pulmonary hypertension. Immediate and long-term results in 42 patients.

Since 1970, forty-two patients with pulmonary hypertension due to chronic, thromboembolic obstruction of the major pulmonary arteries have had pulmonary thromboendarterectomy at the University of California, San Diego, and the San Diego Veterans Medical Centers. Duration of symptoms before admission averaged 4.4 years, with many alternative diagnoses having been made. At admission, 29 patients had class IV disease by New York Heart Association criteria, and 12, class III. Immediately after surgery, pulmonary vascular resistance declined significantly (p less than 0.001) from 897 +/- 352 dynes/s.cm-5 to 278 +/- 135 dynes/s.cm-5. Seven patients with class IV disease died in the postoperative period. Of the 35 survivors (mean follow-up, 28 months), 16 had class I disease; 18, class II; and 1, class III. Of the 17 patients who have returned for cardiac catheterization at 4 to 12 months after surgery, a further decline (p less than 0.05) in pulmonary vascular resistance has occurred. This experience indicates that the disorder is commoner than we previously suspected and that thromboendarterectomy is feasible, even in patients with severe and protracted hemodynamic compromise.

Adult↗
PubMed1987

Pulmonary vascular imaging.

A wide range of pulmonary vascular imaging techniques are available for the diagnostic evaluation of patients with suspected pulmonary vascular disease. The characteristics of any "ideal" technique would include high sensitivity and specificity, safety, simplicity, and sequential applicability. To date, no single technique meets these ideal characteristics. Conventional pulmonary angiography remains the "gold standard" for the diagnosis of acute thromboembolic disease despite the introduction of newer techniques such as digital subtraction angiography and magnetic resonance imaging. Improved noninvasive lower extremity venous testing methods, particularly impedance plethysmography, and ventilation-perfusion scanning can play significant roles in the noninvasive diagnosis of acute pulmonary emboli when properly applied. Ventilation-perfusion scanning may also be useful as a screening test to differentiate possible primary pulmonary hypertension from chronic thromboembolic pulmonary hypertension. And, finally, angioscopy may be a useful adjunctive technique to detect chronic thromboembolic disease and determine operability. Optimal clinical decision-making, however, will continue to require the proper interpretation of adjunctive information obtained from the less-invasive techniques, applied with an understanding of the natural history of the various forms of pulmonary vascular disease and with a knowledge of the capabilities and shortcomings of the individual techniques.

Blood Platelets↗
PubMed1987

Fiberoptic bronchoscopy--diagnostic applications.

Bronchoscopy has an important role in the diagnosis and staging of lung cancer. It is also useful in a more limited role in the diagnosis of infectious, interstitial, and pediatric diseases. Its applications, limitations, and complications in these conditions are reviewed.

Biopsy↗
PubMed1986

Reperfusion pulmonary edema after pulmonary artery thromboendarterectomy.

Pulmonary artery thromboendarterectomy (PAT) is a potentially curative procedure in chronic, major vessel thromboembolic pulmonary hypertension. However, postoperative reperfusion pulmonary edema (RPE) has been a serious complication, often requiring prolonged mechanical ventilation. This entity has been described only anecdotally in the past. To characterize it more fully, we retrospectively analyzed the course and potential determinants of RPE after thromboendarterectomy in 22 patients who had PAT at our institution from 1969 through 1984. Particular attention was directed to clinical data, thrombus location, areas operated, postoperative roentgenograms, and preoperative and postoperative hemodynamic data. In all patients but 1, RPE developed within 72 h after surgery, corresponding to anatomic locations distal to vessels subjected to PAT. Regions of lung not reperfused at surgery were uniformly spared. Pulmonary capillary wedge and/or left atrial pressures preoperatively and postoperatively were not elevated. None of the preoperative data predicted which patients would develop more persistent RPE. These observations suggest that the phenomenon of RPE is a peculiar, focal form of pulmonary edema, the basis for which remains to be defined.

Adult↗
PubMed1985

Transbronchial needle aspiration in the diagnosis of pneumonia in a canine model.

We evaluated the risk, sensitivity, and specificity of transbronchial needle aspiration (TBNA) in a canine model of unilateral Streptococcus pneumoniae pneumonia and compared the results with our previous studies of these parameters in transthoracic needle aspiration (TTN), a catheter-brush (CB), and transbronchial biopsy (TBB) in the same model. The TBNA was performed in 10 dogs with right lower lobe S. pneumoniae pneumonia. The procedure was uncomplicated, but both the sensitivity and specificity were low (3 of 10 cultures yielded S. pneumoniae; only 1 of the 3 was a pure culture). This compares unfavorably with our experience with the other procedures: 9 of 10 cultures were pure with TBB and CB, and the remaining culture was sterile; 10 of 10 were pure with TTN. Given the present unprotected form of the bronchoscopic aspirating needle, TBNA does not appear to be useful in the diagnosis of bacterial pneumonia despite its usefulness in the diagnosis of intrathoracic malignancy.

Animals↗
PubMed1985

Transbronchial needle aspiration in the diagnosis of submucosal and peribronchial bronchogenic carcinoma.

Although exophytic endobronchial lesions can readily be diagnosed by routine forceps biopsy through the fiberoptic bronchoscope, submucosal or peribronchial tumor can be difficult to diagnose with nonsurgical techniques. We evaluated the utility of transbronchial needle aspiration (TBNA) through the fiberoptic bronchoscope in 31 patients presenting with endoscopic abnormalities suggestive of submucosal or peribronchial tumor. TBNA was performed using a 20 g X 1 cm needle, followed by forceps biopsy of the same area. Forceps biopsy was positive in 17 cases (55 percent) and TBNA in 22 (71 percent) (p = .302). The combination of forceps biopsy and TBNA was positive in 27 cases (89 percent), which was significantly better than forceps biopsy alone (p = .00195). In addition, the wash or the brush detected three additional carcinomas, so the combination of TBNA, forceps biopsy, wash, and brush had a diagnostic yield of 97 percent. We conclude that TBNA significantly increases the yield over forceps biopsy alone in the detection of submucosal or peribronchial bronchogenic carcinoma and that the maximal diagnostic yield is obtained by the combination of TBNA, forceps biopsy, wash, and brush when appropriate endoscopic abnormalities are encountered.

Adenocarcinoma↗
PubMed1985

Fiberoptic angioscopy: role in the diagnosis of chronic pulmonary arterial obstruction.

We evaluated the role of fiberoptic angioscopy in eight patients with suspected chronic pulmonary embolic obstruction of the pulmonary arteries. Angioscopy, preceded by ventilation-perfusion lung scans, right-heart catheterization, and pulmonary angiography, resulted in diagnostic changes in four patients: from pulmonary artery agenesis to chronic emboli; from chronic emboli to normal pulmonary arterial intima (primary pulmonary hypertension); from chronic pulmonary emboli to extrinsic compression of a major pulmonary artery (fibrosing mediastinitis); and from suspected agenesis or chronic emboli to a tumor (fibrosarcoma) of the pulmonary artery. Angioscopy also more accurately determined the extent and surgical accessibility of chronic embolic obstruction in the five patients with that disorder; as a result, we decided that the obstruction in one patient was inoperable. No significant complications occurred with angioscopy and we conclude that its direct visualization capability can contribute significantly to the diagnostic evaluation of suspected chronic pulmonary arterial obstruction.

Adult↗
PubMed1985

Carinal forceps biopsy via the fiberoptic bronchoscope in the routine staging of lung cancer.

Main carinal biopsy was carried out in 58 consecutive patients with endobronchial (endoscopically visible) bronchogenic carcinoma. Overall, the results of the biopsy were positive in 8 of 58 patients (13.8%). The biopsy results were positive in 6 of 15 (40%) patients whose carina appeared abnormal as compared with 2 of 43 (4.7%) whose carina appeared normal (P = .0025). In those patients with subtle carinal abnormalities (carinal widening or erythema) but without gross tumor involvement, the biopsy findings were positive in 5 of 14 (36%). Unlike in previous studies, a significant percentage of positive carinal biopsy findings was associated with left upper lobe lesions. There were no complications associated with the procedure. Although the yield on blind carinal biopsies (visually normal carina) with the flexible fiberoptic bronchoscope is lower than that previously reported with the rigid bronchoscope, it remains a low-risk procedure that can spare a number of patients the morbidity and expense of more invasive surgical staging when applied as a routine part of diagnostic bronchoscopy in patients with endoscopically visible bronchogenic carcinoma.

Bronchoscopy↗
PubMed1984

Hemodynamics and gas exchange during angioscopy in the dog.

We have previously developed a technique for the in vivo visualization of the pulmonary arteries in the experimental animal with a fiberoptic instrument (angioscope). To assess the potential hemodynamic and gas exchange effects of angioscopy, we studied five dogs before and after pulmonary embolization. Sequential observations were made of arterial blood gases, mean arterial pressure, pulmonary artery pressure, heart rate, cardiac output, and the electrocardiogram. The most common arrhythmias were ventricular premature contractions which were comparable to those seen with right heart catheterization. Statistically significant, but clinically minor, effects were found on cardiac output, mean arterial pressure, and heart rate in dogs when angioscopy was performed after pulmonary embolization. We conclude that fiberoptic angioscopy does not induce deleterious effects on hemodynamics or gas exchange in the experimental animal, prior to or after embolization.

Animals↗
PubMed1984

The role of transcarinal needle aspiration in the staging of bronchogenic carcinoma.

Transcarinal needle aspiration for staging subcarinal nodes was performed in 134 consecutive patients with suspected bronchogenic carcinoma at the time of diagnostic fiberoptic bronchoscopy using a prototype 20-gauge by 1-cm needle. The aspiration was performed before examination of the lower airways to avoid cellular contamination. Twenty-four patients had benign primary disease and negative needle aspirates. The transcarinal needle aspirate was positive in 15 percent of the 110 patients with bronchogenic carcinoma. There were no false-positives, and the transcarinal needle aspirate was the only evidence of unresectability in 69 percent (11/16) of those in whom it was positive. In addition, two subgroups of patients were identified in whom the aspirate is most likely to be positive--patients with endobronchial tumors (24 percent; 15/63) and those with an abnormal carina at bronchoscopy (38 percent; 8/21). No complication occurred. We conclude that transcarinal needle aspiration is a low-risk procedure that can save a significant number of patients the morbidity and cost of surgical staging and that it should be performed at the time of diagnostic bronchoscopy in all patients with an endobronchial lesion or a visually abnormal carina.

Adult↗