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Biomedical subjects

R A Robbins

Publications and source records attributed to R A Robbins.

At least 127 records · Page 7Linked to original sources

Short-term smoking reduction is associated with reduction in measures of lower respiratory tract inflammation in heavy smokers.

The beneficial effect of short-term smoking reduction in reducing lower respiratory tract inflammation was assessed in 15 healthy heavy smokers. All underwent fibreoptic bronchoscopy and bronchoalveolar lavage and were then treated with at least 20 mg of nicotine gum daily. Self-reported cigarette consumption decreased from 50.7 +/- 2.3 to 18.8 +/- 1.5 (p less than 0.001) cigarettes daily, and expired CO decreased from 48.5 +/- 2.5 to 27.3 +/- 2.5 ppm (p less than 0.001). After two months, repeat bronchoscopy and bronchoalveolar lavage revealed that bronchial inflammation, as assessed by direct inspection, neutrophilia of bronchial lavage fluid, and the number of alveolar macrophages, the number of alveolar neutrophils and the concentration of neutrophil elastase alpha 1-antiprotease complex in alveolar lavage fluid, had improved significantly. The present study suggests that smoking reduction may be associated with an improvement in lower respiratory tract inflammation in heavy smokers and may, if persistent, be an alternative for smokers who cannot, or do not wish, to quit.

Adult↗

Diffuse alveolar hemorrhage in autologous bone marrow transplant recipients.

PURPOSE: The purpose of our work was to evaluate pulmonary complications in autologous bone marrow transplant recipients. PATIENTS AND METHODS: A total of 141 consecutive autologous bone marrow transplant recipients were evaluated. In 29 patients, a clinical syndrome characterized by progressive dyspnea, hypoxia, cough, diffuse consolidation on chest roentgenography, and characteristic bronchoalveolar lavage findings developed over one to seven days. RESULTS: In 29 patients, bronchoalveolar lavage performed by sequential instillation and aspiration of 20-ml aliquots of normal saline resulted in recovered lavage fluid that became progressively bloodier with each recovered aliquot. Autopsy and bronchoalveolar lavage in these patients revealed no pathogens that accounted for the clinical findings. Since the later aliquots sample predominantly alveolar material, this syndrome was termed diffuse alveolar hemorrhage (DAH). DAH was associated with a high inpatient mortality rate (23 of 29 died versus 14 of 112 without DAH, p less than 0.001) and was associated with age over 40 years, solid malignancies, high fevers, severe mucositis, white blood cell recovery, and renal insufficiency (p less than 0.05, compared with patients without DAH). However, DAH was not associated with prolonged prothrombin or partial thromboplastin times or decreased platelet counts compared with patients without DAH. CONCLUSION: DAH is a frequent cause of respiratory compromise and a major cause of mortality in autologous bone marrow transplant recipients.

Adult↗

Bronchial epithelial cells release chemotactic activity for lymphocytes.

Lymphocytes can frequently be observed in association with bronchial tissues. One mechanism that might account for this association is that bronchial epithelial cells might release chemotactic factors for lymphocytes. To test this hypothesis, bovine bronchial epithelial cells were cultured in serum-free media, and the supernatant fluids were harvested and evaluated for lymphocyte chemotactic activity using a blind-well chamber technique. Media alone attracted few lymphocytes (12 +/- 2 cells/high power field), but in contrast, there was a significant increase in the number of cells attracted by supernatant fluids obtained from bronchial epithelial cell cultures (40 +/- 6 cells/high power field, P = 0.002). The activity was dose dependent and was demonstrated to be chemotactic activity by checkerboard analysis. Partial characterization of the activity revealed it was not extractable into ethyl acetate but was partially inactivated by trypsin and heat (100 degrees C, 15 min). The responding cells were predominantly T-helper lymphocytes as shown by monoclonal antibody staining, with a smaller proportion being B-lymphocytes. Molecular sieve column chromatography revealed multiple peaks of lymphocyte chemotactic activity, with three of the peaks preferentially attracting T-helper lymphocytes and one of the peaks preferentially attracting B-lymphocytes. These data demonstrate that bronchial epithelial cells can release chemotactic factors for lymphocytes and suggest that bronchial epithelial cells may modulate their local population of immune effector cells.

Animals↗

Bronchial epithelial cells release chemoattractant activity for monocytes.

Lung macrophages are monocyte-derived cells that play a central and essential part in local immunity. Because the bronchial epithelial cells that line the airway can modulate their local cellular environment by releasing chemotactic factors for neutrophils, lymphocytes, and fibroblasts, we postulated that the bronchial epithelial cells might release chemotactic activity for monocytes. To test this hypothesis, bovine bronchial epithelial cells were isolated and cultured. The supernatant fluids were collected at 12, 24, 36, 48, 72, 96, and 120 h and evaluated for monocyte chemotactic activity, using a blind-well chamber technique. The supernatant fluids possessed significantly greater chemotactic activity than medium alone, with optimal migration contained in supernatant fluids harvested at 72 h (5.8 +/- 2.3 vs. 39.8 +/- 2.8 cells/high-power field, P less than 0.001). Partial characterization of the released monocyte chemotactic activity revealed that the cells released a low-molecular-weight lipid-soluble chemotactic factor after 24 h in culture, but in contrast, a high-molecular-weight protein chemokinetic factor was released after 72 h in culture. These findings suggest that bronchial epithelial cells may release chemotactic activity for, and thus may modulate the recruitment of, monocytes into bronchial passages.

Adult↗

Intraluminal airway inflammation in chronic bronchitis. Characterization and correlation with clinical parameters.

In order to characterize intraluminal airway inflammation in subjects with chronic bronchitis, bronchoscopy and bronchoalveolar lavage were performed in 28 subjects with chronic bronchitis with fixed airway obstruction and, for comparison, 15 asymptomatic smokers and 25 normal nonsmoking volunteers. The chronic bronchitics had a cough productive of sputum on most days of the month for 6 months in the preceding 2 yr, had at least one exacerbation requiring medical intervention in each of the previous 2 yr, and had an FEV1 less than 76% of predicted without response to bronchodilator. During bronchoscopy the airways were assessed for visual evidence of inflammation by assigning them a score, the bronchitis index, that graded the airways according to the apparent severity of airway edema, erythema, friability, and secretions. Bronchoalveolar lavage was performed by sequentially instilling and retrieving with gentle suction five 20-ml aliquots of sterile normal saline into each of three separate lobes. The first aliquots, the "bronchial" sample, were pooled and processed separately from the final four aliquots, the "distal" sample. Cell counts, cell differentials, and albumin were determined for both the bronchial and distal samples. In order to correlate inflammation with clinical parameters, sputum was collected for 24 h prior to bronchoscopy; spirometry was performed just prior to bronchoscopy, and smoking histories were obtained. Visual inspection of the airways, as quantified by the bronchitis index, demonstrated significantly more evidence for inflammation in the chronic bronchitics than in either the asymptomatic smokers or the normal subjects. The bronchial sample lavage fluids from the chronic bronchitics tended to contain more cells (6.1 +/- 2.2 x 10(6) cells) than the bronchial sample fluids from the asymptomatic smokers (3.6 +/- 0.6 x 10(6) cells) or normal subjects (3.7 +/- 0.5 x 10(6) cells). Furthermore, the chronic bronchitics had a higher percentage of neutrophils in their bronchial lavage fluid (35.8 +/- 5.6%) than did either the asymptomatic smokers (20.7 +/- 2.6%, p = 0.0001) or the normal subjects (10.3 +/- 5.6%). The distal sample lavage fluid also recovered more neutrophils from both the chronic bronchitics (15.0 +/- 4.2%, p = 0.0012) and asymptomatic smokers (5.7 +/- 1.3%, p = 0.002) than from the normal subjects (2.8 +/- 0.4%). The chronic bronchitics were divided into two groups: those with low (less than 20%) and those with high (greater than 20%) bronchial sample neutrophils. Those with higher bronchial sample neutrophils had significantly more sputum production and lower FEV1, FEV1/FVC, and FEF25-75 than did the subjects with lower bronchial sample neutrophils.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

Bronchial epithelial cells produce lung fibroblast chemotactic factor: fibronectin.

The interaction between the epithelial cells and the subjacent mesenchymal cells in the airway is thought to play a major role during tissue repair after airway injury and lung morphogenesis. To evaluate this interaction, we cultured human lung fibroblasts, and bovine and human bronchial epithelial cells, and determined that bronchial epithelial cell-conditioned medium has a chemotactic activity for lung fibroblasts. This activity had the characteristics of protein: it was nondialyzable, heat-labile, pepsin-labile, acid-stable, and lipid-inextractable. Molecular sieve chromatography on Sephadex G-150 and affinity chromatography on gelatin-Sepharose revealed that there was one peak of chemotactic activity in high molecular weight range, which bound to gelatin, thus suggesting that the chemotactic factor might be fibronectin. Production and secretion of fibronectin into the culture media were demonstrated by biosynthetic incorporation of radioactive amino acid into fibronectin followed by immunoprecipitation on SDS-PAGE and autoradiography. Release into the culture medium was confirmed by ELISA. The identity of fibronectin as the chemotactic activity was confirmed by the addition of antifibronectin antibody to the conditioned medium, which inhibited chemotaxis in dose-dependent manner. Thus, bronchial epithelial cells produce fibronectin which can function as a chemotactic factor for lung fibroblasts. This production of fibronectin by bronchial epithelial cells may play an important role in regulating interaction between the bronchial epithelial cells that line the lumenal surface of the bronchial epithelial wall and the mesenchymal fibroblasts that underlie the bronchial epithelial basement membrane.

Antibodies↗

Neutrophil chemotactic factors in bacterial pneumonia.

The influx of neutrophils into the lung is a prominent feature in patients with bacterial pneumonia. Since neutrophils migrate in response to chemotactic factors, chemotactic activity was evaluated in bronchoalveolar lavage (BAL) fluid obtained from 12 patients with bacterial pneumonia and ten normal control subjects. Chemotactic activity was greatly elevated in the BAL fluid of the pneumonia patients compared with control subjects (p less than 0.01). To partially characterize the chemotactic factors present in the lavage fluid of the patient group, molecular sieve chromatography was performed on the lavage fluid, and at least three peaks of chemotactic activity were identified. Since the molecular weight of the smaller peaks approximated the molecular weight of two known chemotactic factors, C5a and leukotriene B4, these factors were measured in lavage fluid by radioimmunoassay. C5a was detectable in none of the normal subjects but was detectable in four of 14 BAL samples obtained from the patients. Leukotriene B4 was detectable in all subjects and was significantly elevated in the pneumonia patients (552 +/- 95 vs 81 +/- 16 pg/ml, p less than 0.01). These findings demonstrate that elevated neutrophil chemotactic activity is present in the lungs of patients with bacterial pneumonia and suggest that C5a and leukotriene B4 may account, at least in part, for this increase.

Adolescent↗

Immunolocalization of proteoglycan types in aortas of pigeons with spontaneous or diet-induced atherosclerosis.

The location of different proteoglycan (PG) types in the developing atherosclerotic lesion was examined by the use of monoclonal antibodies directed toward specific epitopes on distinct PG types. Sections of aorta were prepared from young White Carneau pigeons fed an atherogenic diet to induce lesions rich in lipid-laden macrophages and from older pigeons that had naturally-occurring atherosclerotic lesions. Monoclonal antibodies (MAb) 3-B-3, 9-A-2, or 2-B-6 and 5-D-4, recognizing delta Di-6S generated from chondroitin 6-sulfate (C6S) PG; delta Di-4S generated from dermatan sulfate (DS) PG and from chondroitin 4-sulfate (C4S); and sulfated poly N-acetyllactosamine sequences common to keratan sulfate (KS), respectively, were used to localize PG types by indirect immunofluorescence. In normal aorta, C6S PG was localized primarily in the media and showed a fluorescent gradient (inner media greater than outer media greater than intima greater than adventitia). In the atherosclerotic plaque, major immunoreactivity was observed using MAb 9-A-2 or 2-B-6, whereas lesser amounts were observed with 3-B-3. Patterns of immunoreactivity differed; 9-A-2 or 2-B-6 appeared to be associated with cells whereas 3-B-3 appeared to be intercellular. Although normal aorta was negative for antibody 5-D-4, recognizing KS, atherosclerotic plaques were consistently positive for this antibody. The pattern of 5-D-4 reactivity appeared to be intercellular. Except for immediately below the lesion, no reactive product using 5-D-4 was observed in the media. No major differences in distribution of PG were observed between naturally-occurring or cholesterol-induced fibrous plaques. These results indicate that both 4-sulfated PG and a previously undescribed KS glycoconjugate are major components of the atherosclerotic lesion.

Animals↗

Mechanisms of neutrophil recruitment to the lung by grain dust exposure.

Inhalation of grain dusts can cause symptoms of both acute and chronic bronchitis, which has been associated with a neutrophilic inflammatory response in the lung. Since this influx of neutrophils may potentially result in bronchial injury, mechanisms of neutrophil recruitment to grain dust were examined. Sterile, aqueous grain dust extracts were prepared from settled dusts of grain sorghum, corn, oats, and soybeans. The extracts were evaluated for their ability to directly attract human neutrophils using a blindwell neutrophil chemotaxis assay. Each extract was found to possess significant chemotactic activity compared to control (p less than 0.01). To evaluate if the dusts could attract neutrophils indirectly by activating humoral inflammatory mechanisms, the grain dust extracts were evaluated for their ability to activate the complement system. When incubated with normal human serum, each of the grain dusts caused cleavage of the complement proteins C3 and properdin factor B (PFB). Importantly, the grain dust extracts lead to the generation of C5a, a potent neutrophil chemoattractant generated by complement activation. Since activation of the alveolar macrophage to release chemotactic activity represents an additional indirect mechanism of neutrophil recruitment, an extract from grain sorghum dust was evaluated for its ability to stimulate guinea pig and human alveolar macrophages to release neutrophil chemotactic activity. The results demonstrate that supernatants obtained from alveolar macrophages cultured in the presence of grain sorghum dust extract possessed increased chemotactic activity compared to controls (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Biomechanical Phenomena↗

Contributions to the history of psychology: XLVIII. Ancient Greek roots of the assumptions of modern clinical psychology.

This paper is an account of studies of the linguistic transformation that took place in ancient Greece between the eighth and fourth centuries B.C., searching for factors which contribute to the shift in how humans perceived themselves. The group or force-field consciousness of the men of the Iliad and the linguistic factors which allowed "individuality" to emerge by the time of Plato is explored. The account relates the emergence of the notion of "madness" to the development of the individual and asks whether madness is an artifact of individuality and explores the relationship of these developments to our present underlying assumption of a duality in human nature composed of the rational and the irrational.

Greece, Ancient↗

Capacity for substrate utilization in oxidative metabolism by neurons, astrocytes, and oligodendrocytes from developing brain in primary culture.

Neuron, astrocyte, and oligodendrocyte cultures which were established from developing rat brain were examined for their utilization of glucose, ketone bodies, and free fatty acids by oxidative processes. 14CO2 production was measured in these cells from [1-14C] or [6-14C]glucose; [1-14C]octanoate and [1-14C], [6-14C], or [16-14C]palmitate; and [3-14C]acetoacetate and D(-)-3-hydroxy[3-14C]butyrate. Pyruvate dehydrogenase (EC 1.2.4.1.) and 3-oxoacid-CoA transferase (EC 2.8.3.5) activities were found at high levels in each of the cell populations. Astrocytes and oligodendrocytes produced much more 14CO2 from [1-14C]glucose than from [6-14C]glucose, indicating substantial hexose monophosphate shunt activity. This process was not as active in neurons. All three cell populations readily utilized the ketone bodies for oxidative metabolism at rates 7-9 times greater than they utilized glucose. Only astrocytes were able to utilize fatty acids for 14CO2 production, and the rate of utilization was greater than that of the ketone bodies. We found that the metabolic patterns of these brain cells which were derived from the developing brain complement the nature of the diet of the suckling animal which is rich in fat and low in carbohydrate. They readily utilized the ketone bodies or fatty acids and spared glucose for processes that metabolites of fat cannot fulfill.

Animals↗

Bronchoalveolar lavage: radiographic manifestations.

Bronchoalveolar lavage (BAL) is a safe and well-tolerated procedure in which the lower respiratory tract is sampled through infusion and subsequent aspiration of sterile saline solution. To determine the radiographic changes consequent to this procedure, 25 patients undergoing fiberoptic bronchoscopy and BAL were evaluated prospectively. After lavage, anteroposterior radiographs were obtained immediately and after 30, 90, and 240 minutes, and 24 hours. The degree and site of opacification on the radiographs was graded on a 4+ subjective scale. Sixty-nine lobes were lavaged, but owing to overlap on the radiographs, 52 projected areas were evaluable for radiographic changes. Forty-seven areas of consolidation were identified on the radiographs obtained immediately after lavage. Consolidation was homogeneous and always corresponded to a projected site of lavage. There was a positive correlation between initial opacity on the radiograph and the volume of retained fluid (rs = .60, P less than .001). Consolidation cleared gradually over 24 hours. No patient had clinical pneumonitis. These benign, self-limited radiographic changes are common after BAL and may simulate pulmonary edema, aspiration, or hemorrhage.

Bronchi↗

Activation of the complement system in the adult respiratory distress syndrome.

The adult respiratory distress syndrome (ARDS) is an acute pulmonary disorder characterized by the accumulation of neutrophils within the lower respiratory tract. Because activation of the complement system can generate C5a, a potent neutrophil chemoattractant, complement activation was assessed in both serum and bronchoalveolar lavage fluid obtained from 10 patients with ARDS and compared with that from normal control subjects. Crossed immunoelectrophoresis was used to determine activation of the complement components C3 and properdin factor B (PFB), and radioimmunoassay was used to determine the presence of C5a. Complement activation was not detected either in the plasma or in the lung epithelial lining fluid of the control subjects. In contrast, evidence of C3 activation was found in the plasma of 50% of the patients with ARDS when initially studied; likewise, C3 activation, PFB activation, and C5a could all be detected in the epithelial lining fluid of all patients with ARDS with a single exception. Follow-up bronchoalveolar lavages revealed decreased amounts of C3 activation and C5a 2 to 7 days after the onset of ARDS, and the complement activation had resolved when the patients with ARDS had completely recovered. To determine if the C5a in bronchoalveolar lavage fluid could be responsible for the influx of neutrophils observed in ARDS, epithelial lining fluids obtained from both normal control subjects and from patients with ARDS were fractionated by molecular sieve chromatography. Two distinct fractions of chemotactic activity were found in the ARDS bronchoalveolar lavage fluid.(ABSTRACT TRUNCATED AT 250 WORDS)

Body Fluids↗

Complement component C5 is required for release of alveolar macrophage-derived neutrophil chemotactic activity.

The influx of neutrophils into the alveolar structures can be induced by stimulation of the resident lung phagocyte, the alveolar macrophage, to release a potent neutrophil chemoattractant(s). We hypothesized that the fifth component of complement (C5) on the cell surface may be required for activation of the alveolar macrophage to release neutrophil chemotactic activity. C5 was identified on guinea pig alveolar macrophages by epifluorescent microscopy, flow cytometry, and enzyme-linked immunoabsorbent assay of eluted macrophages. When cultured for 4 h with stimuli that induce the release of chemotactic activity or for 24 h without added stimuli, purified Fab' fragments of a goat anti-C5 antibody significantly inhibited the ability of macrophages to release chemotactic activity as determined by a blindwell chamber method (p less than 0.001, all comparisons). This inhibition of chemotactic activity was not detected when anti-C5 antibody was added after the culture period. In contrast, anti-C3 antibody had no inhibitory effect at 4 h or at 24 h (p greater than 0.2, all comparisons). Partial characterization of released chemotactic activity revealed it was of low molecular weight, partially lipid soluble, and not inhibited by C5a chemotactic factor inactivator. These studies suggest that C5 may have a regulatory role in the release of chemotactic activity by alveolar macrophages.

Animals↗