Biomedical subjects

R Smejkal

Publications and source records attributed to R Smejkal.

9 recordsLinked to original sources

PubMed1998

Dual blockade of P-selectin and beta2-integrin in the liver inflammatory response after uncontrolled hemorrhagic shock.

BACKGROUND: Neutrophil infiltration is a characteristic feature of the hepatic injury associated with prolonged hypotension. Previous work has already stressed the important contribution of neutrophil-endothelial cell interactions in the organ injury seen after hemorrhagic shock. Single-blockade strategies using monoclonal antibodies (MAbs) against either selectin or integrin receptors have been demonstrated to be effective in limiting the tissue inflammatory response observed in this clinical disorder. One unexplored topic is the additive effect(s) and the potential antiinflammatory properties of the combined blocking of P-selectin plus beta2-integrin in the liver inflammatory response after uncontrolled hemorrhagic shock in rats. STUDY DESIGN: Sprague-Dawley rats (n = 64) weighing 250-300 g were included in a three-phase model of uncontrolled hemorrhagic shock. A prehospital phase consisted of 90 minutes of fluid resuscitation with lactated Ringer's solution to reach a mean arterial pressure (MAP) of 40 mmHg; a hospital phase consisted of 60 minutes of hemostasis and fluid resuscitation with lactated Ringer's solution to reach a MAP of 80 mmHg; and the third phase was 3 days of observation. All rats had 3 mL/100 g of blood volume shed during the initial 15 minutes. At 30 minutes, 75% tail amputation produced uncontrolled hemorrhagic shock. Four groups were randomized (n = 16 per group), and treatment at the beginning of resuscitation included normal saline (group 1); anti-P-selectin MAb, RMP-1 (group 2); anti-beta2-integrin MAb, WT.3 (group 3); or anti-P-selectin plus anti-beta2-integrin MAbs (group 4). The following indices were evaluated: fluid requirements for resuscitation, liver injury tests, liver tissue myeloperoxidase, and liver histology. RESULTS: Dual blockade of P-selectin and beta2-integrin significantly reduced fluid requirements for resuscitation (p < 0.05). We also observed a statistically significant improvement (p < 0.05) in tests demonstrating hepatic injury, myeloperoxidase in hepatic tissue, and histology studies. Survival was increased from 40% in controls to 60% with the dual-blockade treatment. CONCLUSIONS: These results indicate that dual-blockade strategies aimed at P-selectin and beta-integrin provided a protective effect in the liver inflammatory response after uncontrolled hemorrhagic shock in rats. Although dual blockade was more effective than either individual blockade alone, questions remain about the possible redundancy in the inflammatory adhesion pathways after this clinical condition.

Alanine Transaminase↗

PubMed1997

Sialyl Lewis(x) analog improves liver function by decreasing neutrophil migration after hemorrhagic shock.

BACKGROUND: Little is known about the changes in the hepatic microcirculation and the leukocyte-endothelial adhesion processes during the early reperfusion period after resuscitation in hemorrhagic shock. P-selectin and its natural ligand Sialyl Lewis(x) (SLe(x)) are involved in the early stages of reperfusion events leading to neutrophil migration. Therefore, the aim of this study was to investigate the effect of the administration of CY-1503 [corrected], a synthetic SLe(x) analog, in the liver inflammatory response and neutrophil migration after hemorrhagic shock. MATERIALS AND METHODS: Rats, each weighing 275 to 300 grams, were subjected to 60 minutes of pressure controlled hemorrhagic shock. After this period, animals were resuscitated according to the following protocol: shed blood was reinfused to equal 50% of the total volume bled, and the other 50% was replaced with 3x volume of Ringer's lactated solution. Animals were divided into sham and two study groups to receive vehicle (controls) and CY-1503 [corrected] (10 mg/kg intravenously) diluted in 1 mL of normal saline 45 minutes after initiating hemorrhagic shock. The following parameters were analyzed: 7-day survival, liver injury tests, liver tissue myeloperoxidase as an index of neutrophil infiltration, and liver histology. RESULTS: Survival was significantly increased from 48% in the controls to 90% in the CY-1503 [corrected] treated group. Animals treated with the SLe(x) analog showed significantly better mean arterial blood pressure after 15 minutes after resuscitation. Also, the treated group showed a marked decrease in liver enzymes levels at 5 minutes and 4 hours after reperfusion. Neutrophil migration was significantly ameliorated as reflected by decreased myeloperoxidase levels in the SLe(x) analog treated group. Furthermore, we observed improved histologic damage scores in the treated group when compared with controls. CONCLUSIONS: The SLe(x) analog, CY-1503 [corrected], had a protective effect in ischemic livers by decreasing neutrophil migration after hemorrhagic shock and resuscitation. This protective effect also resulted in improved survival and mean arterial blood pressure after resuscitation.

Animals↗

PubMed1991

Routine initial computed tomography of the chest in blunt torso trauma.

Computer tomography (CT) is an effective technique in the initial evaluation of the abdomen and head following blunt trauma. To evaluate the role of CT of the thorax, a prospective study comparing routine early thoracic CT scanning with initial chest roentgenogram (CXR) was carried out on 73 patients with blunt torso trauma undergoing concomitant abdominal CT examination. Initial CXR and CT scans were interpreted independently by radiologists in a blinded fashion. CXR diagnosed more bony injuries than CT, while the CT identified pulmonary contusions and effusions more accurately. Only those contusions diagnosed by CXR proved clinically significant. Patient treatment was changed in one case based on CT findings. In the absence of CXR findings, chest CT scanning frequently identifies abnormalities with limited clinical significance. Although more sensitive, CT of the thorax has a limited role in the initial emergent evaluation of victims of blunt torso trauma.

Abdominal Injuries↗

PubMed1991

Blood antibodies and uncrossmatched type O blood.

The immediate transfusion of uncrossmatched type O blood in the initial resuscitation of the trauma victim remains controversial. To examine difficulties in crossmatching blood for later transfusions after use of uncrossmatched type O blood, we undertook a prospective 23-month study at a level I trauma center. One hundred thirty-five severely injured patients received uncrossmatched type O blood during the study period. Sixty-one patients (45%) died and 76 patients (56%) underwent emergent operation. There were no major transfusion reactions. Six patients had blood antigen-antibodies present on admission, and such antibodies developed in three patients during hospitalization. We conclude that uncrossmatched type O blood may be used safely in the exsanguinating patient, but blood antigen-antibodies, which may complicate later crossmatching, can develop after its use.

ABO Blood-Group System↗

PubMed1989

Injury severity scoring: a comparison of early clinical versus discharge diagnosis.

The Abbreviated Injury Scale (AIS) and the Injury Severity Score (ISS) are objective means of assessing injury. Accepted methodology involves retrospective scoring of injury based on discharge diagnoses. Recently, early clinical scoring, supplemented by review at discharge, has been introduced. A prospective study was instituted to compare these methodologies. Four hundred sixty consecutive victims of blunt trauma were scored using both clinical and retrospective methodologies by independent, blinded observers. Of these, 333 patients had a change in ISS, 174 with a change of greater than four points. The population mean ISS remained unchanged; however, paired values were significantly different (p less than .03). We conclude that either methodology is applicable for studies of large populations of trauma victims. When accurate individual AIS or ISS scoring is required, the clinical method combined with discharge review is most appropriate.

Accidents, Traffic↗

PubMed1989

Myocardial contusion without creatine kinase--MB elevation.

Myocardial contusion after chest trauma remains one of the major complexities of trauma care today. Diagnostic methods such as 12-lead electrocardiography and echocardiography, as well as activity of the biochemical marker creatine kinase and the MB subfraction, have not been shown to be sensitive or specific indicators. We report a case of an intraoperatively proved myocardial contusion without creatinine kinase or creatine kinase MB elevation.

Adult↗

PubMed1988

Pelvic crush injuries with occlusion of the iliac artery.

During a 1-year period, three patients presented with acute traumatic thrombosis of the common or external iliac artery concomitant with a massive crush injury to the pelvis. All had vascular compromise of the involved extremity on initial physical examination, but in two patients with open pelvic trauma, exsanguination, major visceral injury, hypothermia, and a coagulopathy precluded emergency vascular reconstruction. Both required hindquarter amputation for adequate debridement. The third patient presented without exsanguination or visceral trauma. Angiography and vascular reconstruction were undertaken, but myonecrosis compounded the initial vascular compromise, and eventually required a hip disarticulation for debridement. It was concluded that: exsanguination and/or major visceral injury takes priority over emergency vascular reconstruction; soft-tissue injury may preclude limb salvage despite vascular reconstruction. If a cadaveric limb exists, early radical amputation, including hindquarter amputation, should be undertaken.

Adult↗

PubMed1986

Tubulin synthesis in the regenerating rat superior cervical ganglion: a biphasic response.

Axotomy of a major cranial post ganglionic branch of the superior cervical ganglion of an adult rat resulted in increased radiolabeling of tubulin and microtubule-associated proteins after an in vitro 5-h incubation with [14C]-methionine. The increased incorporation of the radiolabel began at day 1 postoperatively and exhibited a biphasic response, peaking at days 3 and 8.

Animals↗

PubMedDate not supplied

Use of spiral vein graft to bypass occluded subclavian vein.

A patient presented with massive swelling of left arm secondary to left radio-cephalic fistula and ipsilateral subclavian vein occlusion. This was successfully treated with a spiral vein graft interposed between axillary vein and internal jugular vein.

Aged↗