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R Richard

Publications and source records attributed to R Richard.

17 recordsLinked to original sources
PubMed1992

Clinical trials of an intravenous oxygenator in patients with adult respiratory distress syndrome.

In patients with severe adult respiratory distress syndrome, mechanical ventilation may not be able to ensure gas exchange sufficient to sustain life. We report the use of an intravenous oxygenator (IVOX) in five patients who were suffering from severe adult respiratory distress syndrome as a result of aspiration, fat embolism, or pneumonia. IVOX was used in an attempt to provide supplemental transfer of CO2 and O2 and thereby reduce O2 toxicity and barotrauma. All patients were tracheally intubated, sedated, and chemically paralyzed and had a PaO2 < 60 mmHg when the lungs were ventilated with an FIO2 = 1.0 and a positive end expiratory pressure of > or = 5 cmH2O. The right common femoral vein was located surgically, and the patient was systemically anticoagulated with heparin. A hollow introducer tube was inserted into the right common femoral vein, and the furled IVOX was passed into the inferior vena cava and advanced until the tip was in the lower portion of the superior vena cava. IVOX use ranged from 2 h to 4 days. In this group of patients, IVOX gas exchange ranged from 21 to 87 ml x min-1 of CO2 and from 28 to 85 ml x min-1 of O2. One of the five patients survived and was discharged from the hospital. The IVOX transferred up to 28% of metabolic gas-exchange requirements. One patient with a small vena cava showed signs of caval obstruction. Three other patients demonstrated signs of a septic syndrome after the device was inserted.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Canine GM1-gangliosidosis. A clinical, morphologic, histochemical, and biochemical comparison of two different models.

The clinical, morphologic, histochemical, and biochemical features of GM1-gangliosidosis in two canine models, English Springer Spaniel (ESS) and Portuguese Water Dog (PWD), have been compared. The disease onset, its clinical course, and survival period of the affected dogs were similar in both models. Skeletal dysplasia was noted radiographically at 2 months of age, whereas at 4 1/2 months of age there was progressive neurologic impairment. However, dwarfism and coarse facial features were seen only in ESS. Both models had similar deficiency in activity of lysosomal beta-galactosidase, but possessed a normal protein activator for GM1-beta-galactosidase. Both models stored GM1-ganglioside, asialo-GM1, and oligosaccharides in brain. Furthermore, only the PWD stored glycoproteins containing polylactosaminoglycans in visceral organs, and neither model stored them in the brain. Morphologically, both models demonstrated similar storage material in multiple tissues and cell types. The ultrastructure of the storage material was cell-type specific and identical in both models. However, some differences in the lectin staining pattern were noted. Our clinical, biochemical, and histochemical findings indicate that PWD and ESS may represent two different mutations of the beta-galactosidase gene. Moreover, the authors conclude that it is difficult, and inappropriate, to apply the human classification of GM1-gangliosidosis (i.e. infantile, juvenile, and adult forms) to these canine models.

Amniotic Fluid↗
PubMed1991

Clinical, neurophysiological, biochemical and morphological features of eyes in Persian cats with mannosidosis.

The clinical, neurophysiological, morphological and biochemical manifestation of eyes from Persian kittens affected with alpha-mannosidosis were studied. Clinically the disease is characterized by progressive corneal and lenticular opacification. In addition there is asymmetry in shape and latency of signal conductions which were demonstrated by visual evoked potential studies. Morphological and histochemical studies revealed vacuolization of various ocular cell types which stained positively with Concanavalia ensiformis agglutinin (Con A) and wheat germ agglutinin (WGA). Biochemical studies illustrated low activity of acid alpha-mannosidase in cultured keratocytes and abnormal storage of partially degraded oligosaccharides in these cells, in vitreous humor and lens. This comprehensive study of ocular alpha-mannosidosis demonstrates enzyme deficiency which leads to abnormal storage of oligosaccharides in affected cells and is manifested by morphological alterations and functional impairment.

Animals↗
PubMed1990

Glycoprotein storage in Gaucher disease: lectin histochemistry and biochemical studies.

Lectin histochemical studies were performed on formalin-fixed, frozen, and paraffin-embedded tissue sections from 19 patients with glucosylceramide lipidosis (i.e., Gaucher disease). Eleven different lectins were used to identify the specific carbohydrate residues in the undegraded stored compounds in the cytoplasm of Gaucher cells. In all cases studied, Gaucher cells stained with Concanavalia ensiformis agglutinin, Datura stramonium agglutinin, Lens culinaris, Ricinus communis agglutinin-I, and wheat germ agglutinin. These results demonstrated common carbohydrate residues in the undegraded material stored within Gaucher cells and indicated the presence of fucosylated N-linked complex oligosaccharides, and glycans containing N-acetyllactosamine repeating sequences, as well as nonreducing terminal beta-galactosyl and sialyl residues. In order to confirm these findings using biochemical methods, livers and spleens from Gaucher patients and controls, and from a patient with Niemann-Pick disease type C (included for comparison) were digested with Pronase and the resulting glycopeptides separated by gel filtration into fractions with high and low molecular weight. In the high-molecular-weight fractions from livers of Gaucher patients, the levels of sugars corresponding to N-linked glycans, as measured by gas-liquid chromatography, were elevated over those in controls. In the high-molecular-weight fractions from spleens, the levels of the same sugars were elevated in both Gaucher and Niemann-Pick type C patients. Digestion of the glycopeptides with endo-beta-galactosidase, which specifically cleaves polylactosaminoglycans, showed the presence of material containing N-acetyllactosamine repeating units in Gaucher liver glycopeptide fractions, but not in control and Niemann-Pick type C derived glycopeptide fractions. Our histochemical and biochemical studies demonstrated that in addition to glucosylceramide, affected tissues of patients with Gaucher disease accumulate glycoproteins. This accumulation could not have been predicted on the basis of the primary enzymatic defect.

Carbohydrates↗
PubMed1989

Steady-state levels of pro-dynorphin-related end-products from the brain of the amphibian, Xenopus laevis.

Steady-state analyses of prodynorphin-derived opioid peptides were conducted on acid extracts of the brain of the frog. Xenopus laevis. Radioimmunoassays specific for dynorphin A(1-17), dynorphin A(1-8), alpha-neoendorphin and dynorphin B coupled with gel filtration chromatography and reverse phase high performance liquid chromatography were used. The major prodynorphin-related end-product detected was alpha-neoendorphin. Interestingly, Leu-enkephalin was also detected. Since the Xenopus proenkephalin precursor does not contain the Leu-enkephalin sequence, these data suggest that some of the prodynorphin-related end-products had been cleaved to yield Leu-enkephalin.

Animals↗
PubMed1986

Effects of breathing a normoxic He-O2 gas mixture on exercise tolerance and VO2 max.

The purpose of these experiments was to compare the effects of breathing air (79% N2-21% O2) and a normoxic helium oxygen gas mixture (He-O2) (79% He-21% O2) on maximal oxygen uptake (VO2 max) and work tolerance during both incremental and high-intensity constant load exercise. First, eight subjects underwent two separate short incremental cycle ergometer exercise tests until the subject could not maintain the desired power output. Second, four subjects exercised to exhaustion on two separate occasions at a constant exercise intensity (100% VO2 max). Each exercise protocol required the subject to breathe air on one test and a normoxic He-O2 mixture on an additional occasion. Data analysis revealed higher (P less than 0.05) minute ventilations, an increased time to exhaustion, and a greater VO2 max during He-O2 breathing in both exercise conditions. Small but significant (P less than 0.05) differences existed in the percent hemoglobin saturated with O2 (% SO2) at exercise demands greater than 120 W during the incremental experiment and during each minute of the constant load test with He-O2 giving the higher value. These data support the hypothesis that breathing a normoxic He-O2 gas mixture during exercise elevates VO2 max and increases exercise tolerance. Further, although it appears that breathing a He-O2 mixture results in higher %SO2 during intense exercise, the increase in arterial O2 content is small and probably does not fully account for the higher VO2 max observed under these conditions.

Adult↗
PubMed1985

Unilateral Meniere's disease: is the contralateral ear normal?

Certain investigations in patients with unilateral Meniere's disease may on occasion show abnormalities in the completely symptomless contralateral ear. These tests include transtympanic electrocochleography, the acetazolamide cochlear hydration test, vestibular aqueduct tomography, and caloric testing. Eventually these ears may well become symptomatic. Previous studies have shown that otoadmittance changes are a sensitive indicator of glycerol-induced intracochlear pressure alterations in hydropic ears, but do not occur in patients without Meniere's disease. Otoadmittance parameters were evaluated in the asymptomatic ears of 73 consecutive patients with unilateral Meniere's disease. Satisfactory traces and adequate dehydration were achieved in fifty-nine. A significant change in the maximum conductance, similar to that often seen in symptomatic hydropic ears, was found in twenty-four cases (40.7%). The presence of functional abnormalities in well over one-third of asymptomatic ears means that they cannot be used as controls in clinical research studies. Furthermore, recognition of contralateral latent hydrops at the initial otologic assessment may modify the subsequent treatment strategy.

Acoustic Impedance Tests↗
PubMedDate not supplied

[Sclerosing injections of oesophageal varices. Analysis of 247 cases treated between 1964 and 1977 (author's transl)].

The authors analyse 247 cases of haemorrhagic oesophageal varices treated using sclerosing injections of Quinine-Urea between 1964 and 1977. Portal hypertension as a result of intrahepatic block accounted for 83% of the patients (alcoholic cirrhosis 65%, meta-icteric 12%) and cavernomas 11%. Sclerosing injections were used in patients refused by surgeons (85%) or after the failure of surgery (15%). Only 11 cases were treated during the period of active haemorrhage, and the others during the following weeks. Tolerance of treatment so long as all safety factors were employed routinely in order to deal with any possible haemorrhagic complications. Deaths due to the method totalled 2.8%, including those due to worsening of the underlying disease. Overall results were of 69% survival of more than one year, 40% at more than 3 years and 24% at more than five years. For alcoholic cirrhosis, these figures were respectively 62, 30 and 18%. The prognosis in cases of cavernoma was much better; 80% survival at more than 5 years.

Adolescent↗
PubMedDate not supplied

[Urothorax].

Explore the source record for details and available documents.

Adult↗
PubMedDate not supplied

[Sclerosis of esophageal varices. Results of 10 years experience].

Before they give their results, the authors, whose experience of sclerosis of oesophageal varices under the oesophagoscope has so far involved 157 patients, deal specifically with the problems facing the anaesthetist and resuscitator when this technique is used, tolerance of the product injected and possible accidents. Firstly, they point out the unsuitability of the patients referred to them by their medical or surgical colleagues. By implication therefore, treatment should only be undertaken with the assistance of a team of experienced resuscitators and every precaution taken to mitigate the effects of possible accidents to these patients who are particularly at risk. These cases are mainly characterized by serious haemorrhages (seven cases described, one resulting in death). Oesophageal injury is, on the other hand, the exception where trained personnel are involved (2 minor mucosal tears out of more than 800 oesophagoscopies). Finally, secondary parietal oesophageal necrosis occurs. Quininaemia assessment after injection of quinine-urea confirms that the product is being efficiently eliminated. Overall results reveal a survival rate of 61 p. 100 after more than a year and 20 p. 100 after more than than three years. These figures underline the limitations of therapeutic possibilities and the serious prognosis for this result of portal hypertension. This leads the authors to express a wish that the procedure should be used as a measure to prevent haemorrhage as soon as the presence of varices is realized. On the other hand, they reject on practical grounds emergency sclerosis of oesophageal varices, as a direct heamostatic method, since, according to their statistics, this almost invariably results in failure.

Esophageal and Gastric Varices↗