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PubMed1997

[Clinical study on action of artificial respiration produced by pressing in massage under anesthesia for lumbar intervertebral disc prolapse].

OBJECTIVE: To observe whether the gas exchange is sufficient for the requirement of body when the patient was prone in position and pressed in the course of massage under intravenous anesthesia with sodium pentothal (SP) for the treatment of lumbar intervertebral disc prolapse. METHODS: The oxygen would not be given to the patients whose heart and lung functions were good during the course of anesthesia and massage, respiratory function and blood gas analysis were studied on 20 patients selected randomly. RESULTS: Tidal volume was smaller and respiratory rate was faster than normal respiration. Saturation pulse oxygen was still normal in all patients. There were no significant changes in blood gas analysis before spinal injection and after massage (P > 0.05). CONCLUSION: The pressing could attain the action of artificial respiration. The respiration pattern was similar to high frequency positive pressure ventilation. The action of vibration and diffusion had normal respiratory effect.

Adult↗
PubMedDate not supplied

Normal pulmonary geometric changes due to respiration: evaluation with inspiratory and expiratory spiral CT.

RATIONALE AND OBJECTIVES: To investigate the pattern of physiological pulmonary geometric changes in the longitudinal direction due to respiration. MATERIALS AND METHODS: Spiral CT scans of the lung were obtained in 20 normal subjects at maximal inspiration and expiration, each with a table feed time of 10 mm/sec, collimation of 10 mm, and continuous sections of 5 mm in thickness. Utilizing the pulmonary vessels or bronchi as the reference points and comparing the points of these structures shown on the CT images taken at both respiratory phases, the distance of excursion in the longitudinal direction during respiration was examined. Excursion of pulmonary structures was examined from the upper edge of the manubrium to the top of the diaphragm in three lung zones in the coronal direction. RESULTS: A significant linear correlation between the distance from the upper edge of the manubrium to the structure and the distance of its excursion was found for all three lung zones (r = 0.84, p < 0.01 for the anterior zone; r = 0.89, p < 0.01 for the middle zone; r = 0.91, p < 0.01 for the posterior zone). The mean value of displacement in posterior zone was significantly greater (p < 0.01) than that in the middle zone, which was significantly greater (p < 0.01) than that in the anterior zone at each level. CONCLUSION: We have described the normal longitudinal displacement patterns of the pulmonary structures due to respiration. These findings may be applied to the diagnosis of pulmonary diseases.

Female↗
PubMed1990

Cheyne-Stokes respiration in patients recovering from acute cardiogenic pulmonary edema.

Cheyne-Stokes respiration is characterized by crescendo-decrescendo fluctuations in tidal volume and respiratory rate interrupted by central apneas. It has long been associated with cardiac disease and has often been cited as a poor prognostic indicator, yet the incidence and immediate significance of CSR in the setting of acute cardiogenic PE is not well defined. Therefore, we studied 95 patients who required MVS because of PE. Breathing patterns were monitored by continuous respiratory inductive plethysmography for a minimum of 12 hours of spontaneous respiration after recovery from PE; CSR was noted in 42 patients (44 percent). There were no significant differences between patients with PE and CSR and those with only PE in regard to LVEF (mean +/- SD, 36 +/- 18 percent vs 33 +/- 16 percent; p = 0.55), reinstitution of MVS within 48 hours (4.8 percent vs 17.0 percent; p = 0.065), or in-hospital mortality (16.7 percent vs 26.4 percent; p = 0.255). We conclude that CSR is a relatively common breathing pattern in patients who required MVS because of cardiogenic PE and does not portend a poor immediate prognosis in this population.

Aged↗
PubMed1964

THE PERFORMANCE OF RESPIRATORS USED IN THE TREATMENT OF RESPIRATORY INSUFFICIENCY.

Mechanical ventilators may be required for the treatment of inadequate ventilation, intractable left heart failure and cerebral edema. Each situation requires different ventilator characteristics. The performance of the Blease P3, Engström, Mörch Piston, Bird Mark 7 and 8 and Bennett PR1 and PR2 respirators has been studied. The factors governing choice of respirator in specific clinical situations are described.

Brain Diseases↗
PubMed1999

Improved brain and muscle mitochondrial respiration with CoQ. An in vivo study by 31P-MR spectroscopy in patients with mitochondrial cytopathies.

We used in vivo phosphorus magnetic resonance spectroscopy (31P-MRS) to study the effect of CoQ10 on the efficiency of brain and skeletal muscle mitochondrial respiration in ten patients with mitochondrial cytopathies. Before CoQ, brain [PCr] was remarkably lower in patients than in controls, while [Pi] and [ADP] were higher. Brain cytosolic free [Mg2+] and delta G of ATP hydrolysis were also abnormal in all patients. MRS also revealed abnormal mitochondrial function in the skeletal muscles of all patients, as shown by a decreased rate of PCr recovery from exercise. After six-months of treatment with CoQ (150 mg/day), all brain MRS-measurable variables as well as the rate of muscle mitochondrial respiration were remarkably improved in all patients. These in vivo findings show that treatment with CoQ in patients with mitochondrial cytopathies improves mitochondrial respiration in both brain and skeletal muscles, and are consistent with Lenaz's view that increased CoQ concentration in the mitochondrial membrane increases the efficiency of oxidative phosphorylation independently of enzyme deficit.

Adenosine Diphosphate↗
PubMed2006

Competition between oxygen and nitrate respirations in continuous culture of Pseudomonas aeruginosa performing aerobic denitrification.

Continuous culture of P. aeruginosa was conducted with nitrate-containing media under the dilution rates (D) of 0.026, 0.06, and 0.13/h and the dissolved oxygen concentrations (DO) of 0-2.2 mg/L. The bacterium performed simultaneous O(2) and nitrate respiration in all of the systems studied. For each D, the (apparent) cell yield from glucose (Y(X/S)) was lower at zero DO, but did not change substantially with non-zero DO. In non-zero DO systems, Y(X/S) increased with increasing D, and when fit with a model considering cell death, gave the following parameters: maximum cell yield Y(X/S) (m) = 0.49, maintenance coefficient M(S) = 0.029 (/h), and cell decay constant k(d) = 0.014/h. The same model failed to describe the behaviors of zero-DO systems, where neither glucose nor nitrate was limiting and the limiting factor(s) remained unknown. The cell yield from accepted electron (Y(X/e)) was however relatively constant in all systems, and the energy yield per electron accepted via denitrification was estimated at approximately 69% of that via O(2) respiration. A closer examination revealed that increasing DO enhanced O(2) respiration only at extremely low DO ( <0.05 mg/L), beyond which the increasing DO only slightly increased its weak inhibition on denitrification. While O(2) was the preferred electron acceptor, the fraction of electrons accepted via denitrification increased with increasing D.

Algorithms↗
PubMed1988

Respiration supported nitrogenase activity of isolated Rhizobium meliloti bacteroids.

Bacteroids having a high level of respiration-supported nitrogenase activity were isolated from nitrogen-fixing alfalfa root nodules. Gentle maceration under anaerobic conditions in the presence of sodium succinate and a fatty acid scavenging agent were employed in this method. A large proportion of isolated bacteroids retained a triple membrane structure as shown by transmission electron microscopy. Dicarboxylic acids of the TCA cycle (malate, fumarate, succinate), but not glutamate or aspartate, supported sufficient respiratory activity to supply the nitrogenase system with ATP and reducing equivalents and to protect the nitrogenase system from inactivation by 4% oxygen over a period of 20-30 min. Sugars did not support nitrogenase activity in intact bacteroids. The properties of the isolated bacteroids were ascribed to minimal damage to the cytoplasmic membrane and peribacteroidal membrane during isolation. With succinate as substrate and oxygen as terminal electron acceptor, initial nitrogenase activity was determined at 4% oxygen in the gas phase of the assay system employed. At this oxygen concentration, the sustained rate of acetylene reduction by respiring bacteroids was linear up to 30 min. Bacteroid activity declined rapidly with time of exposure to oxygen above 4% in the gas phase. The optimum temperature range for this activity was 10-20 degrees C. Nitrogenase activity was measurable at incubation temperatures below 10 degrees C under 4% oxygen. Functionally intact bacteroids had little nitrogenase activity under anaerobic conditions in the presence of an external source of ATP and reductant. Treatment of the bacteroids with chlorpromazine eliminated respiration-supported activity and rendered the bacteroid cell membrane permeable to external ATP. Bacteroids treated with chlorpromazine had high acetylene reducing activity with external ATP and dithionite in the absence of oxygen.

Carboxylic Acids↗
PubMed1983

The respiration-linked limiting step of tumor cell transition from the non-cycling to the cycling state: its inhibition by oxidizable substrates and its relationships to purine metabolism.

The recruitment into the cycling state of resting Yoshida AH 130 hepatoma cells was studied with respect to its dependence on respiration in an experimental system wherein the overall energy requirement for this recruitment can be supplied by the glycolytic ATP. The G1-S transition of these cells, unaffected by 2,4-dinitrophenol (DNP) at concentrations which uncouple the respiratory phosphorylation, is impaired either by blocking the electron flow to oxygen by antimycin A or by adding an excess of some oxidizable substrates, chiefly pyruvate and oxalacetate. An experimental analysis, focused on pyruvate activity, showed that the inhibition of cell recruitment into S is not related to the depressing effects of this substrate on aerobic glycolysis of tumor cells, nor is it modified by forcing, in the presence of DNP, pyruvate oxidation through the tricarboxylic acid cycle as well as the overall oxygen consumption. Addition of suitable concentrations of preformed purine bases (mainly adenine), completely removes the block of the G1-S transition produced either by the excess of oxidizable substrates or by antimycin A. These findings indicate the existence of a respiration-linked step in purine metabolism, which restricts the above transition and is equally impaired by blocking the respiratory chain or by saturating it with an excess of reducing equivalents derived from unrelated oxidations. The inhibitory effects of pyruvate and antimycin A can be largely removed by the addition of folate and tetrahydrofolate, suggesting that the respiration-linked restriction point of tumor cell cycling involves the folate metabolism and its connections to purine synthesis.

Adenine↗
PubMed1985

An electrochemical method for determination of cell respiration.

The respiration of microorganisms was determined with a sensor composed of microorganisms and an oxygen electrode. The microorganisms (suspensions of about 100 microliters) are sedimented by centrifugation in a special tube on a very thin paper layer (diameter 4 mm). This paper layer is sandwiched between a polyethylene membrane and a dialysis membrane. A linear relationship is obtained between the current and the cell mass of Bacillus subtilis (between 0.05-0.35 mg dry weight per electrode preparation). When an assimilable substrate is added to the measuring solution the respiration rate is increased. It is possible to determine very fast changes in the respiration rates (1-5 sec). The application of this electrode system for investigations of the physiological state of cells during the growth cyclus is demonstrated.

Bacillus subtilis↗
PubMed2002

Respiration-induced B0 fluctuations and their spatial distribution in the human brain at 7 Tesla.

In functional magnetic resonance imaging (fMRI), it is known that physiological influences such as cardiac pulsation, respiration, and brain motion can induce fluctuations in signal intensity and phase. Some of the mechanisms potentially involved in those phenomena are expected to be amplified at higher magnetic fields. This study addresses the issue of B(0) fluctuations induced by susceptibility changes during respiration attributed to movements of chest and diaphragm, and variations in the oxygen concentration. It is demonstrated that respiration-induced resonance offsets (RIROs) are significant at 7T. Data were acquired with an RF pulse (no gradients), multislice echo-planar imaging (EPI), and dynamic 3D fast low-angle shot (3D- FLASH) imaging. Three main observations summarize the experimental findings. First, in FIDs measured after a single RF pulse, a RIRO with a large amplitude was consistently detected, although the average amplitude varied between subjects from 1.45 Hz to 4 Hz. Second, in transverse EPI images obtained in the occipital lobe, the RIRO amplitude showed a monotonic increase along the z axis toward the lungs. Third, a more detailed spatial analysis with 3D-FLASH phase maps revealed that a previously published analytical model can accurately describe the spatial distribution of RIRO. Consequential apparent motions in the EPI series, as well as the implications of slice orientation for correction strategies are discussed.

Brain↗
PubMed2005

Molecular characterization and biological response to respiration inhibitors of Pyricularia isolates from ctenanthe and rice plants.

The molecular profile and the biological response of isolates of Pyricularia oryzae Cavara obtained from ctenanthe to two strobilurins (azoxystrobin, kresoxim-methyl) and the phenylpyridinamine fungicide fluazinam were characterized, and compared with isolates from rice plants. Five different isozymes (alpha-esterase, lactate, malate, isocitrate and sorbitol dehydrogenases) and five random decamer primers for RAPD-PCR were used to generate molecular markers. Using unweighted pair-group with arithmetic average analysis, ctenanthe isolates were found to form a separate group distinct from that of the rice isolates for both sets of markers. Amplified polymorphic sequences of mitochondrial cytochrome b that were digested with Fnu4HI or StyI revealed no differences among Pyricularia isolates at amino acid positions 143 or 129 which confer resistance to strobilurins in several fungi. In absence of the alternative respiration inhibitor salicylhydroxamic acid (SHAM) the three fungicides showed inferior and variable efficacy, with a trend toward the rice isolate being less sensitive. The addition of SHAM enhanced the effectiveness of all fungicides against isolates regardless of their origin. Appressorium formation was the most vulnerable target of action of the respiration inhibitors and azoxystrobin the most effective. This is the first report of a comparison between the molecular profiles and sensitivities to respiration inhibitors for Pyricularia oryzae isolates from a non-gramineous host and from rice.

Acrylates↗
PubMed2001

Sensitivity of mitochondrial respiration to different inhibitors in Venturia inaequalis.

The sensitivity of Venturia inaequalis field isolates to inhibitors of the cytochrome bc1 complex at the Qo site (QoIs) was characterised at the molecular, biochemical and physiological level, and compared to other respiration inhibitors. Comparison of a sensitive and a QoI-resistant isolate revealed very high resistance factors both in mycelium growth and spore germination assays. Cross-resistance was observed among QoIs such as trifloxystrobin, azoxystrobin, famoxadone, strobilurin B and myxothiazol. In the mycelium growth assay, antimycin A, an inhibitor of the cytochrome bc1 complex at the Qi site, was less active against the QoI-resistant than against the sensitive isolate. The mixture of QoIs with salicylhydroxamic acid (SHAM), an inhibitor of the alternative oxidase, exerted synergistic effects in the spore germination but not in the mycelium growth assay. Thus, the cytochrome and the alternative respiration pathways are assumed to play different roles, depending on the developmental stage of the fungus. Induction of alternative oxidase (AOX) by trifloxystrobin was observed in mycelium cells at the molecular level for the sensitive but not the resistant isolate. Following QoI treatment, respiration parameters such as oxygen consumption, ATP level, membrane potential and succinate dehydrogenase activity were only slightly reduced in Qo-resistant mycelium cells, and remained at much higher levels than in sensitive cells. In contrast, no difference was observed between sensitive and resistant isolates when NADH consumption was measured. Comparison of the cytochrome b (cyt b) gene of the sensitive and resistant isolates did not reveal any point mutations as is known to occur in resistant isolates of other plant pathogens. It is assumed that QoI resistance in V inaequalis may be based on a compensation of the energy deficiency following QoI application upstream of the NADH dehydrogenase of the respiratory chain.

Adenosine Diphosphate↗
PubMed2001

Trypanosoma cruzi: inhibition of parasite growth and respiration by oxazolo(thiazolo)pyridine derivatives and its relationship to redox potential and lipophilicity.

Chagas' disease constitutes a therapeutic challenge because presently available drugs have wide toxicity to the host and are generally ineffective in the chronic stages of the disease. A series of oxazolo(thiazolo)pyridene derivatives were studied on Trypanosoma cruzi epimastigote growth and oxygen consumption and their electrochemical (redox) potentials and lipophilicity. The derivatives produced different degrees of parasite growth and respiration inhibition on CL Brener, LQ, and Tulahuen strains of T. cruzi epimastigotes. Respiratory chain inhibition appears to be a determinant of the trypanosomicidal activity of these compounds, since a significant correlation between respiration and culture growth inhibition was found. A similar correlation was found, within the different structural subfamilies, between toxic effects and the ability of the compounds to be oxidized in aqueous media. The inhibition of respiration and of parasite growth in culture increases with the lipophilicity of the substituents on the oxazolopyridine nucleus. No difference in the action of these derivatives was found among the different parasite strains. It is concluded that these compounds may have a potential usefulness in the treatment of Chagas' disease.

Animals↗
PubMed2001

Increased sensitivity of mitochondrial respiration to inhibition by nitric oxide in cardiac hypertrophy.

Cardiac hypertrophy is a significant risk factor for the development of congestive heart failure (CHF). Mitochondrial defects are reported in CHF, but no consistent mitochondrial alterations have yet been identified in hypertrophy. In this study selective metabolic inhibitors were used to determine thresholds for respiratory inhibition and to reveal novel mitochondrial defects in hypertrophy. Cardiac hypertrophy was produced in rats by aortic banding. Mitochondria were isolated from left ventricular tissue and the effects of inhibiting respiratory complexes I and IV on mitochondrial oxygen consumption were measured. At 8 weeks post-surgery, 65+/-2% complex IV inhibition was required to inhibit respiration half maximally in control mitochondria. In contrast, only 52+/-6% complex IV inhibition was required to inhibit respiration half maximally in mitochondria from hypertrophied hearts (P=0.046). This effect persisted at 22 weeks post-surgery and was accompanied by a significant upregulation of inducible nitric oxide synthase (iNOS, 3.0+/-0.7-fold, P=0.006). We conclude that respiration is more sensitive to complex IV inhibition in hypertrophy. Nitric oxide is a well documented inhibitor of complex IV, and thus the combination of increased NO(.)from iNOS and an increased sensitivity to inhibition of one of its targets could result in a bioenergetic defect in hypertrophy that may be a harbinger of CHF.

Animals↗
PubMed1999

Status of respiration and ATP content in arsenite resistant Leishmania mexicana amazonensis.

Cellular ATP and rate of respiration are important for the cell survival. We have analyzed both the parameters in wild type and arsenite resistant Leishmania mexicana amazonensis. There was no significant change observed in the rate of respiration and cellular ATP content between drug resistant cells (resistance to 30 microM of sodium arsenite) and wild type cells. Further, we have tested the effect of higher concentrations (i.e. 100 microM and 500 microM) of sodium arsenite on the ATP content of the cells. An elevated level of ATP was observed only in wild type cells after short term exposure (2 h) to 100 microM of the drug, whereas, drug resistant cells initially resist with higher toxic dosage of drug (i.e. 500 microM) but failed to maintain the normal ATP level. In conclusion, respiration and ATP is not a prime event associated with drug resistance in Leishmania. Resistance to metals like arsenic and antimony in Leishmania is multifactorial events.

Adenosine Triphosphatases↗
PubMed1994

In vitro and in vivo effects of methyl isocyanate on rat brain mitochondrial respiration.

The present study deals with the in vitro and in vivo effects of methyl isocyanate (MIC) on rat brain mitochondrial function. Addition of MIC to tightly coupled brain mitochondria in vitro resulted in a mild stimulation of state 4 respiration, abolition of respiratory control, decrease in ADP/O ratio, and inhibition of state 3 oxidation. The oxidation of NAD(+)-linked substrates (glutamate + malate) was more sensitive (fourfold) to the inhibitory action of MIC than succinate while cytochrome oxidase was unaffected. Administration of MIC subcutaneously at a lethal dose affected respiration only with glutamate+malate as the substrate (site I) and caused a 20% decrease in state 3 oxidation leading to a significant decrease in respiratory control index while state 4 respiration and ADP/O ratio remained unaffected. As both the malondialdehyde and iron contents of brain mitochondria were not altered, it may be inferred that the observed in vivo inhibition of state 3 oxidation is induced by MIC through systemic stagnant hypoxia leading to ischemia of brain, which further contributes to the cerebral hypoxia.

Animals↗
PubMed1989

Control of mitochondrial respiration in the heart in vivo.

The role of the hydrolysis products of adenosine triphosphate (ATP), adenosine diphosphate (ADP) and inorganic phosphate (Pi), in the control of myocardial respiration was evaluated in vivo using 31P NMR. These studies were conducted to evaluate whether increases in the ATP hydrolysis products can be detected through the cardiac cycle or during increases in cardiac work. 31P NMR data acquisitions gated to various portions of the cardiac cycle (50 msec time resolution) revealed that cytosolic ATP, ADP and Pi did not change over the course of the cardiac cycle. These metabolites were also monitored during steady-state increases in cardiac work in conjunction with measurements of coronary blood flow and oxygen consumption. No changes were observed during 2 to 3 fold increases in myocardial oxygen consumption induced by various methods. These results demonstrate that the cytosolic ATP, ADP, and Pi concentrations remain relatively constant throughout the cardiac cycle and during physiological increases in cardiac work and oxygen consumption. Furthermore, it is shown that ADP and Pi cannot be solely responsible for the regulation of cardiac respiration in vivo based on the in vitro Km values of these compounds for oxidative phosphorylation. It is concluded that other mechanisms, working in concert with the simple kinetic feedback of ATP hydrolysis products, must be present in the cytosol to provide control of myocardial respiration in vivo.

Adenosine Diphosphate↗
PubMed1990

The specific functions of menaquinone and demethylmenaquinone in anaerobic respiration with fumarate, dimethylsulfoxide, trimethylamine N-oxide and nitrate by Escherichia coli.

The respiratory activities of E. coli with H2 as donor and with nitrate, fumarate, dimethylsulfoxide (DMSO) or trimethylamine N-oxide (TMAO) as acceptor were measured using the membrane fraction of quinone deficient strains. The specific activities of the membrane fraction lacking naphthoquinones with fumarate, DMSO or TMAO amounted to less than or equal to 2% of those measured with the membrane fraction of the wild-type strain. After incorporation of vitamin K1 [instead of menaquinone (MK)] into the membrane fraction deficient of naphthoquinones, the activities with fumarate or DMSO were 92% or 17%, respectively, of the activities which could be theoretically achieved. Incorporation of demethylmenaquinone (DMK) did not lead to a stimulation of the activities of the mutant. In contrast, the electron transport activity with TMAO was stimulated by the incorporation of either vitamin K1 or DMK. Nitrate respiration was fully active in membrane fractions lacking either naphthoquinones or Q, but was less than or equal to 3% of the wild-type activity, when all quinones were missing. Nitrate respiration was stimulated on the incorporation of either vitamin K1 or Q into the membrane fraction lacking quinones, while the incorporation of DMK was without effect. These results suggest that MK is specifically involved in the electron transport chains catalyzing the reduction of fumarate or DMSO, while either MK or DMK serve as mediators in TMAO reduction. Nitrate respiration requires either Q or MK.

Anaerobiosis↗