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At least 1,153 records · Page 64Linked to original sources
PubMed1995

Effects of immunization with Cryptococcus neoformans cells or cryptococcal culture filtrate antigen on direct anticryptococcal activities of murine T lymphocytes.

Immunizing CBA/J mice with intact Cryptococcus neoformans cells or with a cryptococcal culture filtrate antigen (CneF) induces an anticryptococcal delayed-type hypersensitivity response. Recently, it has been shown that two phenotypically different T-cell populations are responsible for delayed-type hypersensitivity reactivity in mice immunized with intact cryptococcal cells, whereas only one of those populations is present in mice immunized with soluble cryptococcal antigens in complete Freund's adjuvant (CFA). The purpose of this study was to determine if differences occur with regard to direct anticryptococcal activity between T-lymphocyte-enriched populations from mice immunized with intact viable or dead cryptococcal cells and similar cell populations from mice immunized with the soluble cryptococcal culture filtrate antigen, CneF, emulsified in CFA. The percentage of lymphocytes which form conjugates with C. neoformans and the percentage of cryptococcal growth inhibition in vitro are greater with T-lymphocyte-enriched populations from mice sublethally infected with C. neoformans or from mice immunized with intact heat-killed cryptococcal cells in the presence or absence of CFA than with lymphocyte populations from mice immunized with CneF-CFA. Enhanced anticryptococcal activity of T lymphocytes could be induced by immunizing mice with heat-killed C. neoformans cells of serotype A, B, C, or D as well as by immunizing with a similar preparation of an acapsular C. neoformans mutant but not by immunizing with CFA emulsified with CneF prepared from any one of the C. neoformans isolates. These data indicate that the soluble cryptococcal culture filtrate antigens do not induce the same array of functional T lymphocytes as whole cryptococcal cells.

Animals↗
PubMed1997

Definition of Mycobacterium tuberculosis culture filtrate proteins by two-dimensional polyacrylamide gel electrophoresis, N-terminal amino acid sequencing, and electrospray mass spectrometry.

A number of the culture filtrate proteins secreted by Mycobacterium tuberculosis are known to contribute to the immunology of tuberculosis and to possess enzymatic activities associated with pathogenicity. However, a complete analysis of the protein composition of this fraction has been lacking. By using two-dimensional polyacrylamide gel electrophoresis, detailed maps of the culture filtrate proteins of M. tuberculosis H37Rv were generated. In total, 205 protein spots were observed. The coupling of this electrophoretic technique with Western blot analysis allowed the identification and mapping of 32 proteins. Further molecular characterization of abundant proteins within this fraction was achieved by N-terminal amino acid sequencing and liquid chromatography-mass spectrometry. Eighteen proteins were subjected to N-group analysis; of these, only 10 could be sequenced by Edman degradation. Among the most interesting were a novel 52-kDa protein demonstrating significant homology to an alpha-hydroxysteroid dehydrogenase of Eubacterium sp. strain VPI 12708, a 25-kDa protein corresponding to open reading frame 28 of the M. tuberculosis cosmid MTCY1A11, and a 31-kDa protein exhibiting an amino acid sequence identical to that of antigen 85A and 85B. This latter product migrated with an isoelectric point between those of antigen 85A and 85C but did not react with the antibody specific for this complex, suggesting that there is a fourth member of the antigen 85 complex. Novel N-terminal amino acid sequences were obtained for three additional culture filtrate proteins; however, these did not yield significant homology to known protein sequences. A protein cluster of 85 to 88 kDa, recognized by the monoclonal antibodies IT-57 and IT-42 and known to react with sera from a large proportion of tuberculosis patients, was refractory to N-group analysis. Nevertheless, mass spectrometry of peptides obtained from one member of this complex identified it as the M. tuberculosis KatG catalase/peroxidase. Thus, the detailed mapping of M. tuberculosis proteins, combined with state-of-the-art analytical techniques such as mass spectrometry, provides a basis for further analysis and rapid identification of biologically relevant molecules.

Amino Acid Sequence↗
PubMed1997

Analysis of culture filtrate and cell wall-associated antigens of Mycobacterium paratuberculosis with monoclonal antibodies.

Proteins secreted by Mycobacterium species have been suggested as major immune targets in the early phase of infection. In this study, we sought to identify specific antigens in culture filtrates and in soluble cell extracts of Mycobacterium paratuberculosis. The release of antigens into the culture medium during growth of the bacilli and the distribution of specific epitopes within the Mycobacterium species were investigated by immunoblot analysis with monoclonal antibodies (MAbs) raised against M. paratuberculosis antigens. MAb B6A interacted with a cellular antigen with an apparent molecular mass of 34.5 kDa in lysates of M. paratuberculosis. MAb B6A did not interact with lysates from any other mycobacterial species, suggesting recognition of an M. paratuberculosis species-specific epitope. MAb FL1-A1 reacted with an antigen of 44.3 kDa in M. paratuberculosis and a 9-kDa antigen in Mycobacterium kansasii. MAb PII-B1 reacted with concanavalin A (ConA)-binding cellular and filtrate molecules of M. paratuberculosis and with lysates of Mycobacterium kansasii and Mycobacterium avium 18. The affinity-purified glycosylated antigens migrated as a diffuse band of between 35 and 45.6 kDa and reacted strongly with ovine and bovine paratuberculosis serum and polyclonal serum against M. tuberculosis lipoarabinomannan antigens. These glycoconjugates were the earliest antigens detected in culture filtrates of M. paratuberculosis. Deglycosylation of the ConA-binding molecules with alpha-mannosidase enzyme abolished the reaction with MAb PII-B1 and with bovine but not ovine paratuberculosis serum, suggesting selective immunogenicity in the different animal species.

Animals↗
PubMed1998

Two-dimensional electrophoresis for analysis of Mycobacterium tuberculosis culture filtrate and purification and characterization of six novel proteins.

Culture filtrate from Mycobacterium tuberculosis contains molecules which promote high levels of protective immunity in animal models of subunit vaccination against tuberculosis. We have used two-dimensional electrophoresis for analysis and purification of six novel M. tuberculosis culture filtrate proteins (CFPs): CFP17, CFP20, CFP21, CFP22, CFP25, and CFP28. The proteins were tested for recognition by M. tuberculosis-reactive memory cells from different strains of inbred mice and for their capacity to induce a skin test response in M. tuberculosis-infected guinea pigs. CFP17, CFP20, CFP21 and CFP25 induced both a high gamma interferon release and a strong delayed-type hypersensitivity response, and CFP21 was broadly recognized by different strains of inbred mice. N-terminal sequences were obtained for the six proteins, and the corresponding genes were identified in the Sanger M. tuberculosis genome database. In parallel we established a two-dimensional electrophoresis reference map of short-term culture filtrate components and mapped novel proteins as well as already-known CFP.

Amino Acid Sequence↗
PubMed2006

Members of the 30- to 32-kilodalton mycolyl transferase family (Ag85) from culture filtrate of Mycobacterium avium subsp. paratuberculosis are immunodominant Th1-type antigens recognized early upon infection in mice and cattle.

The characterization of protective antigens is essential for the development of an effective, subunit-based vaccine against paratuberculosis. Surface-exposed and secreted antigens, present abundantly in mycobacterial culture filtrate (CF), are among the well-known protective antigens of Mycobacterium tuberculosis and Mycobacterium bovis. Culture filtrate, prepared from Mycobacterium avium subsp. paratuberculosis ATCC 19698 grown as a surface pellicle on synthetic Sauton medium, was strongly and early recognized in experimentally infected B6 bg/bg beige mice and cattle, as indicated by elevated spleen cell gamma interferon (IFN-gamma) secretion and lymphoproliferative responses of peripheral blood mononuclear cells, respectively. Strong proliferative and ex vivo IFN-gamma responses against antigen 85 (Ag85) complex (a major protein component from M. bovis BCG culture filtrate) could be detected in cattle as early as 10 weeks after oral M. avium subsp. paratuberculosis infection. Synthetic peptides from the Ag85A and Ag85B components of this complex were strongly recognized, whereas T-cell responses were weaker against peptides from the Ag85C protein. A promiscuous T-cell epitope spanning amino acids 145 to 162 of Ag85B (identical sequence in M. bovis and M. avium subsp. paratuberculosis) was identified in experimentally infected cattle. Finally, young calves, born from cows with confirmed paratuberculosis, demonstrated proliferative responses to purified, recombinant Ag85A and Ag85B from M. avium subsp. paratuberculosis. These results indicate that the M. avium subsp. paratuberculosis Ag85 homologues are immunodominant T-cell antigens that are recognized early in experimental and natural infection of cattle.

Acyltransferases↗
PubMed1962

MECHANISM OF ACTION OF THE TOXIN OF BACILLUS ANTHRACIS II. : Alkaline Phosphatasemia Produced by Culture Filtrates of Various Bacilli.

Slein, Milton W. (Fort Detrick, Frederick, Md.) and Gerald F. Logan, Jr. Mechanism of action of the toxin of Bacillus anthracis. II. Alkaline phosphatasemia produced by culture filtrates of various bacilli. J. Bacteriol. 83:359-369. 1962.-A factor which produces hyperphosphatasemia after intravenous injection into animals has been found in culture filtrates of several bacilli. The factor appears not to be lecithinase, although it has been found only in culture filtrates of microorganisms, such as Bacillus cereus variants and B. thuringiensis, which are known to produce lecithinase. The factor has been shown to be different from the protective antigen fraction of the toxin of B. anthracis. The phosphatasemic response can be prevented by mixing the factor with antiserum before injection. Immunological tests indicate that the centers of ossification may be a principal source of the excess alkaline phosphatase which is liberated into the bloodstream. However, moderate changes in bone alkaline phosphatase activity levels, brought about by the development of scurvy in guinea pigs or by treatment of scorbutic guinea pigs with ascorbic acid, did not seem to affect the phosphatasemic response of the animals. Marked release of alkaline phosphatase occurs when slices of rabbit epiphyseal bone or kidney cortex, or suspensions of leukocytes, are incubated with small amounts of the phosphatasemia factor.

Journal Article↗
PubMed1964

IMMUNOGENIC SUBSTANCES IN CULTURE FILTRATES AND LYSATES OF PASTEURELLA TULARENSIS.

Hatch, Melvin T. (University of Utah, Salt Lake City), and Paul S. Nicholes. Immunogenic substances in culture filtrates and lysates of Pasteurella tularensis. J. Bacteriol. 88:566-573. 1964.-Culture filtrates and lysates of Pasteurella tularensis were tested for immunogenicity in mice subsequently infected with either strain 425 or 425 F4G. The efficacy of the vaccines varied with dosage and was significantly dependent upon methods of preparation. The optimal procedures for the production of an immunologically potent vaccine included: (i) aging the cultures after growth under partial anaerobiosis at 37 C, and (ii) inactivating the cells with phenol or formaldehyde. An unusual "survival phenomenon" was suggested when mice were administered large doses of cell-free vaccines and subsequently large doses of moderately virulent P. tularensis. The data indicated that the filtrates and lysates elicited an immune response sufficient to protect against an active infection with strains 425 or 425 F4G, and that the challenge dose per se stimulated an enhanced immunity. Furthermore, this survival phenomenon was demonstrable when immunized mice were subsequently given massive doses of strain 425 and challenged with approximately 1,000 ld(50) of the fully virulent strain Schu. On the basis of our data, we have hypothesized that the protective antigens were released into the suspending medium as a result of alterations in the permeability of cells undergoing either complete or partial enzymatic degradation. We believe that the envelope antigens were released from the cell by mechanisms analogous to those causing leakage of intracellular constituents in cells maintained at an incubation temperature in an unfavorable growth environment.

Animals↗
PubMed1964

DIFFERENTIATION OF EXOTOXIN AND OTHER BIOLOGICALLY ACTIVE SUBSTANCES IN PSEUDOMONAS PSEUDOMALLEI FILTRATES.

Heckly, Robert J. (University of California, Berkeley). Differentiation of exotoxin and other biologically active substances in Pseudomonas pseudomallei filtrates. J. Bacteriol. 88:1730-1736. 1964.-Denaturing agents such as phenol, formaldehyde, and urea reduced lethal toxicity and proteolytic activity of partially purified preparations from Pseudomonas pseudomallei at about the same rate. Neither toxin nor enzyme was stable at pH 11, when the solution was adjusted with sodium hydroxide, but there was a slight difference in their rates of inactivation. However, under certain conditions, ammonium hydroxide destroyed most of the enzymatic activity with only a slight effect on lethality. Conversely, toxin was less stable in acid solutions than was the enzyme. Thus, treatment with ammonium hydroxide or acetic acid yielded preparations with either a low or a high enzyme-to-toxin ratio, indicating that lethality was not dependent on enzyme activity. Although proteolysis of any one of the essential factors in the blood coagulation system can inhibit clotting of blood, the potent anticoagulant activity of culture filtrates was not associated with its proteolytic activity, but was directly correlated with lethal toxicity. It is of considerable interest that the necrotoxicity was, however, associated with enzymatic activity and not with lethality. Serological reactivity of the enzyme, as well as its proteolytic activity, was altered by ammonium hydroxide. Similarly, antigenicity and toxicity of the lethal toxin were reduced by acidification. Each acid- or alkali-treated preparation produced a single precipitin line in double diffusion in agar when reacted with antisera produced by injection of crude filtrate. Partially purified preparations, having both lethal and enzymatic activity, produced two lines, one identifiable with the enzyme preparation, and one with the toxin. Furthermore, specific precipitation with the respective antisera removed either enzyme or toxin from crude preparations. Therefore, the lethal exotoxin and proteolytic enzyme are separable entities.

Animals↗
PubMed1988

Monoclonal antibodies produced in BALB.B10 mice define new antigenic determinants in culture filtrate preparations of Mycobacterium tuberculosis.

A panel of monoclonal antibodies were derived from BALB.B10 mice immunized with a culture filtrate from Mycobacterium tuberculosis H37Rv. Of these antibodies, 10 were examined more closely for antigen specificity and interspecies reactivity. Six antibodies were used as immunosorbents for affinity purification of their corresponding antigens. Two monoclonal antibodies (HBT 2 and HBT 11) reacted with a 17-kilodalton antigen, and a competition assay showed that these antibodies are directed against the same epitope or against epitopes that are sterically very close to each other. Monoclonal antibody HBT 12 reacted with the same molecule with which a previously described 38-kilodalton reactive antibody reacted but was directed against a different epitope. Antibody HBT 10 reacted with a culture filtrate of M. tuberculosis but not of Mycobacterium bovis BCG. This latter finding was further studied by testing different preparations of M. tuberculosis H37Rv antigens and, additionally, culture filtrates of four M. tuberculosis and two BCG strains. Interspecies reactivity was assayed by immunoblotting and revealed that the majority of the monoclonal antibodies were specific to M. tuberculosis complex.

Animals↗
PubMed1994

Racial differences in the results of glaucoma filtration surgery: are racial differences in the conjunctival cell profile important?

Conjunctival biopsies were obtained at the time of filtration surgery from 90 patients with glaucoma; 45 of these patients were black and 45 white. Forty nine of the patients (25 black, 24 white) had undergone a primary trabeculectomy. Comparisons between black and white patients were made with respect to the results of surgery and differences in conjunctival cell profile. In agreement with many authors, trabeculectomy was found to be less successful in black patients (67% compared with 80%), although this finding was not statistically significant by survival analysis. In addition, conjunctiva from black patients was found to contain a greater number of macrophages and a smaller number of both mast cells and goblet cells in comparison with white patients. There was a tendency for conjunctiva from black patients to contain more fibroblasts. Conjunctiva obtained from the patients whose filtration surgery subsequently failed was found to contain more fibroblasts, macrophages, and basal epithelial pale cells. A greater number of conjunctival macrophages and possibly fibroblasts in black patients may partially explain the tendency for a lower success rate of filtration surgery in this group of patients.

Adult↗
PubMed1987

Cytopathogenic protein in filtrates from cultures of Propionibacterium acnes isolated from patients with Kawasaki disease.

Propionibacterium acnes may have a role in Kawasaki disease. Filtrates from cultures of P acnes isolated from cervical lymph node biopsy specimens and blood samples from patients with Kawasaki disease were studied and compared with samples from control subjects. After inoculation of human embryo liver cells with filtrates from the patients a cytopathogenic effect and vacuolation were seen. A specific cytopathogenic substance was found in only the filtrates of cultures from patients with Kawasaki disease; it was a protein of about isoelectric point 7.0 with a molecular weight of about 100,000 daltons. The amount of IgG antibody to this cytopathogenic protein was measured by enzyme linked immunosorbent assay (ELISA) in serum samples taken from 63 patients in the acute phase of Kawasaki disease (mean 5.2 (SD 1.1) days after onset of illness), 45 in the subacute phase (mean 23.6 (3.3) days), and 51 in the convalescent phase (mean 18.5 (4.1) months) and from 102 control subjects matched for age. Titres of IgG antibody were significantly raised in patients with Kawasaki disease, particularly in the acute and subacute phases of the illness, compared with in the control subjects. Titres of IgG antibodies to cytopathogenic protein were found to be low in normal children below the age of 4 years but they increased with age thereafter. This may explain why outbreaks of Kawasaki disease, which is most common in children aged under 4, occur every three years.

Antibodies, Bacterial↗
PubMed1977

Characterization of an immunogenic fraction of Pasteurella multocida culture filtrates.

An immunogenic fraction (IF) of Pasteurella multocida strain P-1059 was separated from culture filtrate by Sephadex gel filtration. Additional fractionation of IF with aqueous ether resulted in the glycoprotein-like preparation (GLP) while extraction with aqueous phenol provided the lipopolysaccharide-like preparation (LPP). The unextracted IF contained carbohydrate, protein, and lipid; the GLP contained carbohydrate and protein; and the LPP contained carbohydrate and lipid. The GLP was maximally protective for mice against homologous challenge, and was medially toxic in rabbit skin when compared to the other culture-filtrate preparations; the LPP was maximally toxic in rabbit skin, and was least protective for mice; and the unextracted IF was medially protective for mice, and was least toxic in rabbit skin.

Animals↗
PubMed1979

Enzymatic hydrolysis of cellulosic materials by Sclerotium rolfsii culture filtrate for sugar production.

The hydrolysis of purified celluloses (cotton, Avicel, Cellulose-123, Solka Floc SW40) and cellulosic wastes (rice straw, sugarcane bagasse, wood powders, paper factory effluents) by Sclerotium rolfsii CPC 142 culture filtrate was studied. Factors which effect saccharification such as pH, temperature, enzyme concentration, substrate concentration, produce inhibition, adsorption, and inactivation of enzyme and particle size were studied. Virtually no inhibition (less than 3%) of cellulose hydrolysis by the culture filtrate was observed by cellobiose and glucose up to 100 mg/mL. Filter paper degrading enzyme(s) (but neither carboxymethylcellulase nor beta-glucosidase) was adsorbed on cellulose. The n value in the S. rolfsii system was calculated to be 0.32 for Avicel P.H. 101 and 0.53 for alkali-treated (AT) rice straw indicating penetration of cellulase into AT rice straw. In batch experiments at 10% substrate level, solutions containing 6 to 7%, 3.8 to 4.7%, 4.0 to 5.1%, and 4.2 to 4.9% reducing sugars were produced in 24 to 48 from AT rice straw. AT bagasse, alkali - peracetic acid treated mesta wood and paper factory sedimented sludge effluent, respectively. The main constituent in the hydrolysate from cellulose was glucose with little or no cellobiose, probably due to the high cellobiase content in the culture filtrate.

Carbohydrates↗
PubMed2002

Studies on exudate-depleted sclerotial development in Sclerotium rolfsii and the effect of oxalic acid, sclerotial exudate, and culture filtrate on phenolic acid induction in chickpea (Cicer arietinum).

Exudate depletion from developing sclerotia of Sclerotium rolfsii Sacc. in culture caused reduced size and weight of sclerotia. Germination of exudate-depleted sclerotia was delayed on Cyperus rotundus rhizome meal agar medium when compared with that of control sclerotia. The exudate-depleted sclerotia caused infection in chickpea (Cicer arietinum) plants in a glasshouse. Different temperatures and incubation periods had no effect on the germination ability of the exudate-depleted sclerotia. Oxalic acid, sclerotial exudate, and culture filtrate of S. rolfsii induced the synthesis of phenolic acids, including gallic, ferulic, chlorogenic, and cinnamic acids, as well as salicylic acid, in treated chickpea leaves. Gallic acid content was increased in treated leaves compared with the untreated controls. Maximum induction of gallic acid was seen in both leaves treated with oxalic acid followed by exudate and leaves treated with culture filtrate. Cinnamic and salicylic acids were not induced in exudate-treated leaves. Ethyl acetate fractionation indicated that the sclerotial exudates consisted of gallic, oxalic, ferulic, chlorogenic, and cinnamic acids, whereas the culture filtrate consisted of gallic, oxalic, and cinnamic acids along with many other unidentified compounds.

Basidiomycota↗
PubMed1985

Digital angiography: matched filtration versus mask-mode subtraction.

Matched filtration was compared to mask-mode subtraction in patients undergoing routine intravenous digital subtraction angiography. Images were analyzed for noise and edge sharpness, and the two techniques were compared subjectively by three radiologists. The quantitative results indicated that matched filtration increased the signal-to-noise ratio by an average of 2.23 but did not significantly increase vessel blurring. Subjectively, the observers favored matched filtration over mask-mode subtraction for overall image quality in 26 out of 30 cases (p less than 0.005) in terms of both sharpness and freedom from motion artifacts.

Angiography↗
PubMed1987

Intestinal capillary filtration in experimental diabetes mellitus.

There is indirect evidence that indicates that intestinal transcapillary fluid and solute exchange is significantly altered in diabetes mellitus. To directly assess the dynamics of microvascular fluid and solute exchange in the small intestine (jejunum-ileum), we measured lymph flow, capillary pressure, capillary filtration coefficient, plasma and lymph oncotic pressures, and the osmotic reflection coefficient in anesthetized, fasted control rats and in rats in which diabetes was induced by a single injection of streptozotocin (65 mg/kg ip) 4 wk before the experiments. Diabetes was associated with an increase in lymph flow (by 120%), capillary pressure (by 34%), and capillary filtration coefficient (by 75%) when compared with values from control rats. The transcapillary oncotic pressure gradient was not altered by diabetes. Interstitial fluid pressure, calculated from the measured parameters in the Starling equation, was increased from -1.6 mmHg in control rats to +2.5 mmHg in diabetic animals. Analysis of lymph-to-plasma protein concentration ratios at various lymph flows suggests that the osmotic reflection coefficient in the diabetic intestine is comparable to that obtained in control animals. The results of this study indicate that experimental diabetes mellitus is associated with increases in intestinal capillary pressure and capillary filtration rate but that intestinal capillary permeability is not altered in this disorder.

Animals↗
PubMed1977

Capillary filtration measurement by strain gauge. II. Effects of mannitol infusion.

Maintenance of normal partition of extracellular fluid into vascular and interstitial compartments is a tightly controlled system. One means of studying control of this system is to induce filtration by fluid loading, and to measure associated changes capillary filtration coefficients (CFC) and Starling pressures in a particular vascular bed. We therefore measured responses of the dog hindlimb to isotonic mannitol infusions. Using strain-gauge plethysmography to measure CFC, the Johnson zero-flow technique to measure isogravimetric capillary hydrostatic pressure, and chronically implanted capsules to measure muscular interstitial hydrostatic pressure, we infused isotonic mannitol into anesthetized dogs for 30 min at 20 ml/min and 30 ml/min. There was a sustained 75% increase in CFC in intact hindlimbs, no change in hydrostatic capillary or interstitial pressure, and a 4-5 mmHg rise in filtration pressure due to dilution of serum protein. The most likely mechanism for increased CFC is capillary recruitment, since distension of capillaries requires large increases in hydrostatic pressure. Interstitial fluid compliance appears high. These studies indicate capillary intermittency may be an important mechanism in the disposition of fluid loads.

Animals↗
PubMed1978

Estimation of the filtration coefficient of pulmonary exchange vessels.

Filtration characteristics of the exchange vessels in isolated dog lung were studied by calculating the volume conductance (LP,C) with use of different components of the weight-gain curve following changes in capillary pressure. In one series of lungs, capillary pressure was elevated to levels that produced alveolar edema (29.4 +/- 5.3 (mean +/- SD) mmHg), and total alveolar capillary membrane conductances (LP,T) were calculated using different components of the accumulated weight-gain measurements. These conductance values are similar to those found in the literature for studies in which alveolar edema developed and LP,T was calculated using wet-to-dry weight ratios as a measure of filtered volume. In another series of lungs, capillary pressure was altered by only 5.8 +/- 2.5 mmHg, and LP,C was calculated by estimating the initial filtration rate by an extrapolation method LP,C calculated by use of the extrapolation method (0.71 X 10(-11) cm3/dyn-s) was larger than the LP,T reported in the literature, because LP,T is an estimate of the conductance of the alveolar plus the capillary membrane. Also, for the most calculations of LP,T, tissue forces have changed which causes an overestimation of the filtration driving pressure and thus an underestimate of the capillary volume conductance. After estimating both LP,C and LP,T, the maximum volume conductance of the alveolar membrane (LP,a) was calculated to be 0.13 X 10(-11) cm3/dyn-s.

Animals↗