Search PubMed⌕ Search

Biomedical subjects

M Cardoso

Publications and source records attributed to M Cardoso.

At least 55 records · Page 3Linked to original sources

Renal metabolism and ammoniagenesis during acute respiratory alkalosis in the dog.

Acute respiratory alkalosis (blood pH, 7.60; arterial PCO2, 15 mmHg (1 mmHg = 133.322 Pa); plasma bicarbonate, 14 mM) was induced in nine anesthetized dogs by increasing their respiratory rate and depth. Renal glutamine extraction and ammonia production expressed per 100 mL of glomerular filtration rate did not change during acute hypocapnia, whereas arterial glutamine concentration decreased significantly from 0.47 to 0.36 mM. Hypocapnia did not change plasma potassium concentration and its urinary excretion. Acute hypocapnia increased lactate extraction and pyruvate production, whereas citrate extraction and glutamate and alanine production did not change. Citraturia remained minimal. Renal cortical glutamine concentration fell from 0.64 to 0.38 mM during hypocapnia while alpha-ketoglutarate, glutamate, malate, oxaloacetate, and citrate did not change. Lactate concentration rose from 1.1 to 2.0 mM. Glutamine concentration in the liver and muscle decreased following acute hypocapnia. Our data are compatible with the hypothesis that an acute respiratory alkalosis might not result in any change in the hydrogen ion concentration and (or) gradient between the mitochondrial matrix and the cytosol. Consequently, renal glutamine extraction and ammonia production are not reduced, renal cortical concentrations of relevant metabolites in the ammoniagenic pathway are not changed, and renal handling of citrate remains unaffected.

Acute Disease↗

Evaluation of superior vena cava syndrome by axial CT and CT phlebography.

Transverse axial computed tomography (CT) has been combined with CT digital phlebography to study nine patients with superior vena cava syndrome. Six were due to malignancy, two were secondary to benign disease, and one was a paraneoplastic manifestation. This combined CT approach successfully identified the abnormal morphology of the superior vena cava, demonstrating external compression, encasement, or intraluminal thrombus in all patients and the collateral venous channels in eight. The efficacy and advantages of this technique are discussed. This technique is a rapid, informative, and cost-effective method for the workup of superior vena cava syndrome. The CT digital phlebogram, however, is not successful in regularly and optimally opacifying the normal superior vena cava because of the limited amount of contrast material, dilution effect of the nonopacified incoming flow from the jugular and azygos veins, and the lack of image enhancement from the CT digital scanograms.

Adenocarcinoma↗

Bicarbonaturic effect of acetazolamide in the dog: the influence of graded volume expansion.

Studies were performed in anesthetized dogs to characterize the effect of a progressive volume expansion on the acetazolamide-induced bicarbonaturia. A closed system with urine reinfusion was used in all these experiments. In normovolemic dogs, 24% of the filtered bicarbonate was excreted into the urine while this value reached 62% when a 10% expansion was superimposed on a continuous infusion of acetazolamide. When a single dose of acetazolamide was given, fractional bicarbonate excretion increased from 21% in normovolemic dogs to 46% during 10% expansion. Without acetazolamide administration, 13% of the filtered bicarbonate was excreted during a 10% expansion. The continuous infusion of acetazolamide in normovolemic dogs increased fractional bicarbonate excretion in a progressive fashion, from 25 to 40%. This study shows that an acute volume expansion potentiates markedly the bicarbonaturic effect of acetazolamide, fractional bicarbonate excretion exceeding by far the simple additive effect of acetazolamide and expansion. We speculate that volume expansion might prevent a compensatory rise in acetazolamide-insensitive bicarbonate reabsorption in sites other than the superficial proximal convoluted tubules.

Acetazolamide↗

Immediate adaptation of the dog kidney to acute hypercapnia.

Studies were performed to determine whether ammoniagenesis could adapt instantaneously to acidosis in the dog kidney. Following acute respiratory acidosis, renal glutamine extraction rose acutely in dogs with stable renal blood flow but did not change when the renal blood flow fell by more than 25%. Acute hypercapnia immediately increased renal ammonia production in both groups of dogs. The rate of both glutamine extraction and ammonia production in acutely hypercapnic dogs without hemodynamic changes was comparable to the rates observed in dogs with chronic metabolic acidosis. Furthermore, the renal metabolite profile observed in acute hypercapnia was similar to the pattern described in chronic metabolic acidosis, i.e., a marked fall in renal glutamate and alpha-ketoglutarate concentrations and a fivefold increase in malate and oxaloacetate concentrations. In the liver and muscle, acute hypercapnia induced no significant change in glutamine concentration but glutamate and alpha-ketoglutarate concentrations decreased. Our findings demonstrate that the dog kidney can adapt immediately to acidosis but that hemodynamic change may mask this adaptation.

Acute Disease↗

Detection of hepatic amebic abscesses by infusion tomography.

The liver represents a major challenge for radiologic imaging. A simple method of diagnosing acute inflammatory lesions of the liver by infusion tomography is presented. Results of this technique in 48 consecutive patients with amebic abscesses of the liver are described, and their typical appearance is presented. The test also appears to aid in defining the acuteness of the lesion.

Humans↗

Mediastinitis from odontogenic and deep cervical infection. Anatomic pathways of propagation.

Potentially lethal consequences can quickly occur once the mediastinum is subjected to the ravages of an anaerobic infection. Mediastinitis from odontogenic or deep cervical infections is extremely rare in the era of antibiotic drugs. We have recently encountered five such cases, with a rapid spread of the inflammatory process into the mediastinum resulting in a number of local and systemic complications. All were caused by anaerobic bacteria. Awareness of such complications and early roentgenographic diagnosis lead to prompt surgical drainage, proper antibiotic therapy, and survival after a stormy clinical course. The anatomic pathways between the various fascial planes of the neck and mediastinum will be described.

Adolescent↗

Acute cholecystitis: 137 patients studied by infusion tomography of the gallbladder.

Clinical experience with inflammatory cholecystopathy recognized in 137 patients studied by infusion tomography of the gallbladder is presented. Diagnostic accuracy was 96% in positive and 94% in negative histologically proven cases. Our results show that infusion tomography of the gallbladder is an accurate, rapid, and safe diagnostic aid in the evaluation of acute cholecystitis. In cases of chronic cholecystitis, infusion tomography may be confirmatory but should not be relied on as a final diagnostic test due to a high percentage of false negative cases.

Acute Disease↗

Infusion tomography of the gallbladder: mechanism of gallbladder wall opacification in experimental acute cholecystitis.

A canine model of acute cholecystitis was used to determine the mechanism of opacification of the gallbladder wall by infusion tomography. The experimental data indicate that opacification of the thickened wall of the gallbladder in acute cholecystitis is a function of hypervascularity and transport of the radiopaque material across the capillary wall by polymorphonuclear cells. Tissue-fluid equilibration of the contrast agent may also play a role.

Acute Disease↗

Antimicrobial resistance in staphylococci from animals with particular reference to bovine Staphylococcus aureus, porcine Staphylococcus hyicus, and canine Staphylococcus intermedius.

Besides their role as commensals on the skin and mucosal surfaces, staphylococci may be involved in a wide variety of diseases in animals. Staphylococcal infections in animals are mainly treated with antimicrobial agents and as a consequence, staphylococci from animal sources have developed and/or acquired resistance to the respective antimicrobial agents. Resistance statistics obtained from national monitoring programmes on staphylococci from cattle and pigs, but also from surveillance studies on staphylococci involved in diseases in dogs are reported and reviewed with regard to their comparability. This review mainly focusses on the genetic basis of antimicrobial resistance in staphylococci of animal origin. Particular attention is paid to resistance to those antimicrobial agents which are most frequently used in veterinary medicine, but also to antimicrobial agents, such as chloramphenicol and mupirocin, which are used in specific cases for the control of staphylococcal infections in pets and companion animals. In addition, plasmids and transposons associated with the respective resistance properties and their ways of spreading between members of the same or different staphylococcal species, but also between staphylococci and other gram-positive bacteria, are described.

Animals↗

Does clinical experience affect occlusal caries diagnosis and sealant recommendation? An in vitro study.

The purpose of this in vitro study was to evaluate the effect of the length of clinical experience on clinician's diagnosing caries and recommending sealants on the occlusal surfaces of permanent/caries free third molars. The third molars involved in this study had been extracted prior to eruption. There were three study groups: dental students, clinicians with five to ten years experience, and clinicians with fifteen to twenty years of practice. Twenty-four percent of the entire sample diagnosed caries. Clinicians with five to ten years of practice diagnosed occlusal caries significantly more than clinicians with fifteen to twenty years of practice, but not significantly differently than senior dental students. Clinicians recommended sealants significantly more than dental students. The most frequent reason for sealant indication was prevention. The results indicate that clinical experience alone does not impart better caries diagnosis and sealant recommendation criteria.

Attitude of Health Personnel↗

[Lymphangiography].

Explore the source record for details and available documents.

Humans↗