PubMed Health⌕ Search

Biomedical subjects

W S Hossne

Publications and source records attributed to W S Hossne.

At least 19 recordsLinked to original sources
PubMed1991

Functional and ultrastructural evaluation of myocardial protection provided by intermittent coronary sinus perfusion in the isolated dog heart.

1. The protection offered by intermittent perfusion of cardioplegic solution through the coronary sinus was investigated in isovolumic blood-perfused dog heart preparations submitted to 60 min of ischemia and 45 min of reperfusion. 2. The preparations were divided into three treatment groups: a) coronary sinus, consisting of preparations (N = 10) perfused through the coronary sinus under 40 cm water pressure; b) aortic, consisting of preparations (N = 10) perfused through the aortic stump under 100 mmHg pressure; c) control, consisting of hearts (N = 9) that were not perfused with cardioplegic solution. 3. Properties of contractile capacity and relaxation were markedly impaired in the control group but were preserved to a comparable extent in the groups perfused with cardioplegic solution through the aorta and coronary sinus. Developed pressure decreased in the control group (before ischemia: 70 +/- 5.5 mmHg; after reperfusion: 35 +/- 12 mmHg; P less than 0.05) and didn't vary in the aortic group (from 69 +/- 4 mmHg to 65 +/- 13 mmHg; P greater than 0.05) and coronary sinus group (from 69 +/- 4.6 mmHg to 60 +/- 10 mmHg; P greater than 0.05). Myocardial relaxation was evaluated by the +/- dp/dt ratio. In the control group there was impairment of myocardial relaxation as indicated by an increase of this index after reperfusion (from 1.05 +/- 0.05 to 1.46 +/- 0.23; P less than 0.05), whereas in the aortic (from 1.10 +/- 0.13 to 1.15 +/- 0.20; P greater than 0.05) and the coronary sinus (from 1.03 +/- 0.14 to 1.08 +/- 0.16; P greater than 0.05) groups there was no variation. Ultrastructural changes in the myocardium were negligible in all three groups at the end of reperfusion. 4. We conclude that intermittent perfusion of a hypothermic cardioplegic solution through the coronary sinus is effective for the protection of the myocardium during total ischemia.

Animals↗
PubMed1984

Effects of dopamine on the pulmonary circulation of the dog.

The effects of dopamine infusion (10 and 20 micrograms kg-1 min-1) on pulmonary arterial pressure (PAP) and pulmonary arterial resistance (PAR) were studied. Experiments were carried out on 60 anesthetized dogs using two different models: model A, with mechanical perfusion of pulmonary circulation and constant left ventricular output, and model B, with physiologic pulmonary perfusion and non-fixed ventricular output. When pulmonary blood flow was constant, dopamine did not change PAP or PAR at either dose. When cardiac output (CO) was allowed to increase, PAP increased with dopamine at both doses, whereas PAR did not change with 20 micrograms kg-1 min-1 dopamine and was reduced by the 10 micrograms kg-1 min-1 dose. We conclude that the increase in PAP could not be explained solely by the rise in CO, but was probably related to an inhibitory effect of dopamine on pulmonary vascular accommodation and to increases in CO, especially when the drug was utilized at higher doses.

Animals↗
PubMed1978

[Hemodynamic disorders resulting from angiography (selective arteriography of the celiac trunk and splenoportography) (author's transl)].

The hemodynamic disorders resulting from the selective arteriography of celiac trunk and splenoportography were studied in 30 dogs. The systemic blood pressure and peripheral pulse rate were considered in these instants: before, during, immediately after and 10 minutes after the angiographic procedures. The analysis of the results obtained permit to conclude that: a) catheterism of the celiac trunk only, increase the systolic systemic blood pressure but does not change the dyastolic; b) during the injection of the contrast medium in the celiac trunk there is an increase of the systemic blood pressure (systolic and dyastolic); c) the selective arteriography of the celiac trunk as well as the splenoportography cause decrease of the systemic blood pressure (systolic and dyastolic) immediately after (1 to 70 seconds) the procedure; d) the decrease of the systemic blood pressure (systolic and dyastolic) is greater after the arteriography than after the splenoportography; e) the decrease of the systemic blood pressure (systolic and dyastolic) is transitory; 10 minutes after the realization of angiographies the systemic blood pressure return to the values observed before the examination; f) selective arteriography of the celiac trunk as well as splenoportography cause decrease of the peripheral pulse rate 10 minutes after the realization of the angiographic procedures.

Angiography↗
PubMed1977

[Scanning with Au198 in experimental hepatic trauma (author's transl)].

Scintiscanning of the liver with Au198 was performed in 30 mongrel dogs. In 18 animals the scanning was performed after 3 different types of hepatic trauma: intraparenchymal hematoma, stab wound and lasceration of liver. In 12 days without hepatic trauma the scanning was performed with purpose to establish the pattern of the normal liver scan in the dog. Results indicate that scintiscanning of the liver is a good propaedeutic method in the evaluation of the presence and localization of traumatic hepatic lesion.

Animals↗
PubMed1977

Surgical anatomy of hepatic veins: morphologic and angiographic study in the dog.

Post-mortem angiography with Schlesinger mass was performed on 30 mongrel dogs to study the hepatic veins and its confluence into the caudal vena cava. The study was complemented by anatomic dissection of the specimens with the purpose of confronting angiographic and morphologic patterns. After sacrificing the animals by section of the cervical vessels, a right thoraco-abdominal incision was made with exposition of the vena cava followed by retrograde catheterization and injection of radiopaque mass through a polyethylene catheter. Two radiographies were performed, one with the dog in a supine position and another of the specimen after its withdraw "en bloc", from the abdominal cavity. The left hepatic division alone or the central and left divisions "en bloc" are the ones that should be used for studies of hepatic ressection, segmentar portal hypertension and lobar liver transplant.

Animals↗
PubMedDate not supplied

[Analysis of ethical aspects on human experimentation included in the instructions for the authors in 139 Brazilian scientific journals].

UNLABELLED: The concern with ethical standards during research in human subjects has been improving in Brazil during the last decade. Analysis of the ethical recommendations in instructions to authors may contribute to understand Brazilian Scientific Journals policies. OBJECTIVE: To evaluate the recommendations related to the ethics of investigation in human subjects in instructions to authors of Brazilian Scientific Journals. MATERIAL AND METHODS: Instructions to authors of 139 Brazilian Scientific Journals in medicine, biomedicine, nursery, odontology and general sciences were analysed. RESULTS: In one hundred ten (79.1%) of the 139 journals no recommendations related to ethics were found; 17 (12.2%) required previous approval by the institutional committee; 3 (2.1%) the procedures should be in accordance with the Declaration of Helsinki; 1 (0.7%) recommends the application of the informed consent; 5 (3.5%) recommend the use of Uniform requirements for manuscripts submitted to biomedical journals and 3 (2.1%) follow no specified rules. Twenty nine journals ask for references in ethics standards: in 15 (51.7%) the information must be included in the text; in 2 (6.8%) the authors must send a letter informing how the ethics standards were followed; in 1 (3.4%) a copy of the approval by the institutional committee must be included; in 1 (3.4%) believed the authors followed the standards and in 10 (34.4%) no specific reference was made. CONCLUSION: These results indicated that the majority of Brazilian Scientific Journals have little concern related to ethical aspects of research in human subjects included in instructions to authors. Even journals that make references to the ethical aspects the recommendations are quite different.

Brazil↗