Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “SHOCK”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 613 records · Page 34Linked to original sources
PubMed1999

The biphasic mystery: why a biphasic shock is more effective than a monophasic shock for defibrillation.

We demonstrate that a biphasic shock is more effective than a monophasic shock at eliminating reentrant electrical activity in an ionic model of cardiac ventricular electrical activity. This effectiveness results from early hyperpolarization that enhances the recovery of sodium inactivation, thereby enabling earlier activation of recovering cells. The effect can be seen easily in a model of a single cell and also in a cable model with a ring of excitable cells. Finally, we demonstrate the phenomenon in a two-dimensional model of cardiac tissue.

Electric Countershock↗
PubMed1988

A Neurospora crassa heat-shocked cell lysate translates homologous and heterologous messenger RNA efficiently, without preference for heat shock messages.

Cell-free protein synthesis systems were prepared from normally-grown (N-lysate) and heat-shocked (HS-lysate) Neurospora crassa mycelium. Although both lysates translated homologous mRNA, the HS-lysate was more active, yielding a higher incorporation of [35S]-methionine into hot TCA-insoluble material and a vastly superior protein synthesis profile. The optimal temperature for translation by both lysates was 21 degrees C; the HS-lysate did not translate heat-shock mRNA preferentially at any temperature tested. Fortuitously, heterologous messenger RNAs from diverse eukaryotic and viral sources - Drosophila, dog pancreas, rabbit globin mRNA, brome mosaic virus, tobacco mosaic virus - were translated by the HS-lysate with an efficiency comparable to that of the commercial rabbit reticulocyte system and superior to the wheat germ system. The cap analogues, m7G(5')ppp(5')G and m7G(5')Gm, inhibited translation significantly.

Animals↗
PubMed1980

Reduction in opiate activation after chronic electroconvulsive shock--possible role for endorphins in the behavioral effects of convulsive shock treatment.

Group-housed adult male Sprague-Dawley rats were given a series of 4 exposures to electroconvulsive shock therapy or equivalent handling without shock (sham treatment). Twenty-four hours after the final treatment the rats were given vehicle or one of two doses of morphine intraperitoneally, and motor activity was assessed by remote sensing for 60 min. A significant shift of the normal dose-response curve towards the right was seen after electroshock. This may point to cross-tolerance between electroshock and opiates upon this behavioral measure. The results are consistent with the hypothesis that endorphins may mediate certain aspects of electroshock.

Animals↗
PubMed2005

Repetitive low-energy shock wave application without local anesthesia is more efficient than repetitive low-energy shock wave application with local anesthesia in the treatment of chronic plantar fasciitis.

BACKGROUND: It remains unclear whether application of local anesthesia (LA) interferes with clinical efficacy of extracorporeal shock wave therapy (ESWT) for chronic plantar fasciitis. AIMS: To evaluate the effect of local anesthesia on the clinical outcome after repetitive low-energy ESWT for chronic plantar fasciitis. METHODS: Eighty-six patients with chronic plantar fasciitis were randomly assigned to receive either low-energy ESWT without LA, given weekly for three weeks (Group I, n=45; 3 x 2000 pulses, total energy flux density per shock 0.09 mJ/mm2) or identical ESWT with LA (Group II, n=41). Primary outcome measure was: Reduction of pain from baseline to month 3 post-treatment in a pain numeric rating scale [0-10 points] during first steps in the morning, evaluated by an independent blinded observer. Calculations were based on intention-to-treat. RESULTS: No difference was found between the groups at baseline. At 3 months, the average pain score was 2.2+/-2.0 points for patients of Group I, and 4.1+/-1.5 points for patients of Group II. The mean between-group difference was 1.9 points (95% CI: [1.1-2.7 points]; P<.001). Significantly more patients of Group I achieved 50% reduction of pain compared to Group II (67% vs 29%, P<.001). CONCLUSION: ESWT as applied should be done without LA in patients suffering from chronic heel pain. LA applied prior treatment reduced the efficiency of low-energy ESWT.

Adult↗
PubMed1990

Extracorporeal shock wave lithotripsy of kidney stones does not induce transient bacteremia. A prospective study. The Copenhagen Extracorporeal Shock Wave Lithotripsy Study Group.

During 58 extracorporeal shock wave lithotripsies 161 blood cultures were drawn to evaluate the incidence of bacteremia during the procedure. Only 3 blood cultures drawn during the procedure yielded bacteria, in all cases probably skin flora contaminants. Post-lithotripsy fever was noted in 29% of the patients, and could not be associated with transient bacteremia and was not influenced by antimicrobial prophylaxis. Patients with a positive urine culture after extracoporeal shock wave lithotripsy may have an increased risk of septicemia.

Adult↗
PubMed2003

Prospective study of the effects of shock wave lithotripsy on renal function: role of post-shock wave lithotripsy obstruction.

OBJECTIVES: To examine the effects of transient post-shock wave lithotripsy (SWL) obstruction on renal function after SWL application for treatment of renal stones in nonobstructed kidneys. METHODS: One hundred consecutive patients with unilateral renal stones were treated by SWL monotherapy. They had a normal laboratory profile and no or controlled urinary tract infection. The urinary tract was radiologically normal. Technetium-99m mercaptoacetyltriglycine and Doppler ultrasonography were performed for all cases a few days before and 1 week and 3 months after SWL. Renal uptake, time to peak clearance, split renal function, effective renal plasma flow, and resistive index were obtained. Patients were stratified into two groups. Group 1 consisted of patients with normal kidneys before SWL and unobstructed kidneys after SWL (n = 84). Group 2 consisted of patients with normal kidneys before SWL that were obstructed 1 week after SWL (n = 16). RESULTS: In group 1, there was a gradual increase in the effective renal plasma flow that became significant after 3 months, up to 114% of the pretreatment levels (P = 0.008). The glomerular filtration rate was stable 1 week after SWL and had increased significantly after 3 months, up to 110% of the pretreatment levels (P = 0.006). In group 2, there was marked deterioration of the effective renal plasma flow and glomerular flow rate to 50.5% (P = 0.002) and 45.8% (P = 0.001), respectively, of the pretreatment levels. These levels returned to the basal levels after 3 months. No significant changes occurred in the resistive index in both groups. CONCLUSIONS: Extracorporeal shock wave lithotripsy has no deleterious effects on the renal function. Post-SWL obstruction, although transient, has a major effect on the renal function on the treated side and must be managed urgently.

Adult↗
PubMed1978

Is shock-induced lung fibrosis reversible? A report on recovery from "shock-lung".

As the consequence of a road accident a 19-year-old man developed respiratory insufficiency. Radiology and gas analysis revealed signs of "shock-lung". Morphometric analysis of a punch biopsy from the lung confirmed the diagnosis. Gas exchange grew worse in spite of conventional treatment. At the end of the third week after the trauma the maintenance of a highly negative fluid balance and the administration of high doses of corticoids were given a trial. The patient recovered. Although no functional pulmonary deficiencies remained, years later the patient still shows radiological evidence of extensive scarring. The lung parenchyma is intact, as judged by morphometric examination. This case shows that patients with "shock lung" can recover, but scars in the extrapulmonary space can remain, even though the lung parenchyma returns to normal.

Accidents, Traffic↗
PubMed2000

Peripheral and intraamygdalar administration of the dopamine D1 receptor antagonist SCH 23390 blocks fear-potentiated startle but not shock reactivity or the shock sensitization of acoustic startle.

Central dopamine (DA) activity is thought to play a role in fear motivation. The aim of the present study was to assess the involvement of DA D1 receptors in emotional learning. The authors report that peripheral and intraamygdalar administration of the specific D1 receptor antagonist SCH 23390 blocked the acquisition of fear-potentiated startle. Analysis of shock reactivity during footshock administration revealed that the learning impairment could not be explained by a diminution in the aversive properties of the unconditioned stimulus. Additionally, systemic and intraamygdalar injection of SCH 23390 did not alter fear expression as measured with the shock sensitization of acoustic startle. The potential contribution of mesoamygdaloid DA to the acquisition and retrieval of conditioned fear responses is discussed.

Amygdala↗
PubMed1990

[Focal size and shock wave pressure: a comparison of three different physical shock wave generators].

Shock-wave delivery and focal size of three different generators-electrohydraulic, electromagnetic and piezoelectric--were compared. Pressure measurements were uniformly made by needle hydrophone (piezoelectric transducer). The smallest focus, 17 x 3 x 3 mm, was achieved with the piezoelectric system (50% isobars), while the focus with the electromagnetic generator was much larger (50 x 7 x 4 mm). With the electrohydraulic generator the focal size of the 60% isobars was 20 mm in the longitudinal axis. The highest pressure, 1512 bar, was achieved with the piezoelectric lithotriptor (mean shock-wave pressure in focus: electrohydraulic 1000 + 100, electromagnetic 1000 + 25, piezoelectric 1400 + 27 bar). The rapid positive pressure rise was followed by a slower pressure fall and a small negative wave. In the focal region the negative pressure wave was between 112 and 200 bar with the electrohydraulic system, 100-146 bar with the electromagnetic one, and 134 bar with the piezoelectric one. The significance of the negative wave is not clear; perhaps it contributes to the development of the cavitation effect and facilitates stone fragmentation.

Electromagnetic Phenomena↗
PubMed2002

CSDBase: an interactive database for cold shock domain-containing proteins and the bacterial cold shock response.

CSDBase (http://www.chemie.uni-marburg.de/~csdbase/) is an interactive Internet-embedded research platform providing detailed information on proteins containing the cold shock domain (CSD). It consists of two separated database cores, one dedicated to CSD protein information, and one to provide a powerful resource to relevant literature with emphasis on the bacterial cold shock response. In addition to detailed protein information and useful cross links to other web sites, CSDBase contains computer-generated CSD structure models for most CSD-containing protein sequences available at NCBI non-redundant protein database at the time of CSDBase establishment. These models were calculated on the basis of known crystal and/or NMR structures using SWISS-MODEL and can be downloaded as PDB structure coordinate files for viewing and for manipulation with other software tools. CSDBase will be regularly updated and is organized in a compact form providing user friendly interfaces to both database cores which allow for easy data retrieval.

Amino Acid Sequence↗
PubMed1988

Sequential shocks are comparable to single shocks employing two current pathways for internal defibrillation in dogs.

Sequential pulse defibrillation using two current pathways was compared with single shocks simultaneously utilizing both pathways in 16 dogs to assess the effects of temporal summation. A cardioverter-defibrillator catheter was positioned via the external jugular vein with the distal 4 cm2 shocking electrode located in the right ventricular apex and the proximal 8 cm2 electrode located in the superior vena cava. Three electrode configurations were tested: (1) single pulse, distal electrode (cathode) to proximal electrode and chest wall patch (common anode), (2) sequential 5 ms pulses with 1 ms interpulse delay, distal electrode (cathode) to proximal electrode (anode) followed by distal electrode (cathode) to chest wall patch (anode), and (3) sequential 10 ms pulses with 1 ms interpulse delay using same current pathways described for configuration 2. The lowest energies resulting in termination of AC induced ventricular fibrillation on four trials were 27.9, 26.6, and 42.3 joules respectively for configurations 1, 2, and 3. The mean energy levels were not significantly different for configurations 1 and 2, both of which were significantly lower than that for configuration 3. The lowest peak voltages terminating ventricular fibrillation on four trials were 595 +/- 176, 521 +/- 134 and 579 +/- 171 volts for configuration 1, 2, and 3. The mean voltage level for configuration 2 was significantly lower than that for configurations 1 and 3, which were not significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1979

Anaphylatoxin-induced shock and two patterns of anaphylactic shock: hemodynamics and mediators.

In the dog, different cardiorespiratory reactions were identified in two types of anaphylactic shock and in C5a-AT (anaphylatoxin)-induced shock. All three types had in common a portal blood pooling with consequent decrease in the venous return, cardiac output, and arterial pressure. In anaphylaxis (a) of the first type, at a low titer of hemagglutinating antibodies, the latent period was 68 s and heart and lung function was unchanged. In the second type, at high titer, the latency was 19 s and pulmonary hypertension and decreased heart contractility occurred. After AT injection pulmonary hypertension appeared with tachypnea and unchanged heart function. Tachyphylaxis, but not cross-over tachyphylaxis against the anaphylactic agent and AT was observed in dogs and isolated guinea pig lungs. AT induced a transient release and a, a prolonged release of histamine, prostaglandins (PGs), and thromboxane A2 and endoperoxides from guinea pig lungs. SRS-A was released only in a. Indomethacin inhibited AT-induced release of PGs in guinea-pig lungs and AT-induced hypotension in the dog though it did not prevent the drop in cardiac output. These model studies suggest that different patterns of clinical a. can occur, depending on the type of antibodies and/or mediators involved.

Anaphylatoxins↗
PubMed1990

Effects of high energy shock wave exposure on renal function during extracorporeal shock wave lithotripsy for kidney stones.

In order to study the effects of high energy shock wave exposure on the kidney in extracorporeal shock wave lithotripsy (ESWL) using Dornier HM3, renal hemodynamics and renal function before and after ESWL were analyzed by 99mTc-DTPA renoscintigraphy. Various urinary enzyme activities (LDH, GOT, GPT, NAG, gamma-GTP) and low molecular protein concentrations (alpha 1-microglobulin, beta 2-microglobulin) before and after ESWL were also compared. In the early phase of the renoscinitgram obtained in the 1st min after injection of 99mTc-DTPA, the time required to reach maximum radioactivity was significantly prolonged after ESWL in both the affected and contralateral kidney. This indicated that renal blood flow decreased in both the affected and contralateral kidney immediately after ESWL. An analysis of the 30-min renoscintigram showed that urinary clearance was delayed in the affected kidney in spite of no overt obstruction due to stone fragments. As for urinary enzyme activities and low molecular protein concentrations, they were standardized by urinary creatinine concentration measured at the same time. Urinary LDH, GOT, GPT and NAG activities remarkably increased on the day of ESWL followed by a decrease close to pretreatment levels on the 4th day, though these levels were still significantly higher than pretreatment levels. Urinary gamma-GPT activity was significantly higher than the pretreatment level only on the day of ESWL. Urinary alpha 1-microglobulin and beta 2-microglobulin concentrations significantly increased on the day of ESWL and were still high on the 4th day.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylglucosaminidase↗
PubMed1987

[Cellular effects of electric shock. Definitions, physical principles, cellular electrophysiology and morphological analysis of the shocked areas].

In this experimental study the electrophysiological changes induced by electric discharges such as used clinically in some arrhythmias refractory to the usual treatments were investigated. With energies comprised between 2 and 80 joules profound modifications of the electrophysiological properties of muscle cells and conduction were observed. These modifications included loss of resting potential, inactivation of the fast sodium flux, increase in refractory periods of conduction and disorders of conduction through the shocked areas with, at most, complete block sometimes reversible when low-energy currents were used. With the same amounts of energy these effects were maximal when the current traversed tissues positioned between the electrodes and decreased in all other cases. Usually, with currents of 10 joules or more all electric activity ceased in a radius of about one centimetre around the shocked area.

Animals↗
PubMed1987

[Extra-corporal shock wave lithotripsy using the HM3 Dornier lithotripter with a modified shock wave generator. Initial clinical reports of experiences].

We report on the clinical application of a modified shock-wave generator for the Dornier Lithotripter HM 3. Stone fragmentation, complication rate, and frequency of auxiliary measures were unchanged in comparison to the former generator. The new shock-wave generator led to markedly reduced patient discomfort during treatment, with the result that more than 50% of all ESWLs could be done with sedation only or without any medication.

Analgesia↗
PubMed1998

Whole body heat shock fails to protect mouse heart against ischemia/reperfusion injury: role of 72 kDa heat shock protein and antioxidant enzymes.

The transgenic mice overexpressing heat shock protein 72 (HSP72) or antioxidants have been reported to be more resistant to myocardial ischemia/reperfusion injury. However, it remains unknown whether whole body heat stress (HS) which may induce HSP72 or endogenous antioxidants affords similar protection in the mouse heart. Adult male mice were treated with either HS (42 degrees C for 15 min) or anesthesia only (SC) against a group of non-stressed controls (NC). At 6 or 24 h later, the hearts were excised and perfused at a constant pressure of 55 mmHg in Langendorff mode. Following 30 min equilibration, hearts were subjected to 20 min of global ischemia and 30 min reperfusion (37 degrees C). Ventricular force was measured by a force-displacement transducer attached to the apex. Leakage of intracellular enzymes (CK, LDH) was measured in coronary efflux. Infarct size was determined by tetrazolium staining. The results showed that no significant differences between HS, SC, and NC groups in ventricular contractile function, CK and LDH release, or infarct size were observed at either time window. HS enhanced the expression of HSP72 in mouse hearts by two- to three-fold, whereas antioxidant enzyme activities (catalase and MnSOD) did not change significantly. We conclude that HS does not precondition the isolated perfused mice hearts against ischemia/reperfusion injury, despite induction of HSP72.

Animals↗
PubMedDate not supplied

Peripheral oxygen availability within skeletal muscle in sepsis and septic shock: comparison to limited infection and cardiogenic shock.

In 40 intensive care patients, tissue oxygen partial pressure distribution within skeletal muscle was measured in order to estimate peripheral oxygen availability. In septic patients with multiple organ failure (n = 20) mean skeletal muscle pO2 was abnormally high (48.8 +/- 8.5 mmHg, p less than 0.001) in contrast to patients with limited infection without sepsis (28.3 +/- 5.9 mmHg, n = 10). Mean muscle pO2 also discriminated between septic and cardiogenic shock (22.6 +/- 6.9 mmHg, p less than 0.001). The characteristic pattern of oxygen availability in septic patients--but not in patients with limited infection--was high skeletal muscle pO2 high whole body oxygen delivery and low whole body oxygen extraction, which was not influenced by the type of pathogenic agent of sepsis. In our patients in severe stage of sepsis, we did not observe local skeletal muscle hypoxia due to microcirculatory disorder. High mean skeletal muscle pO2 suggested reduced oxygen consumption within tissue rather than reduced oxygen transport to tissue in sepsis.

Bacterial Infections↗
PubMed1994

A novel kinase cascade triggered by stress and heat shock that stimulates MAPKAP kinase-2 and phosphorylation of the small heat shock proteins.

MAPK-activated protein kinase-2 (MAPKAP kinase-2) is activated in vitro by the p42 and p44 isoforms of MAPK (p42/p44MAPK). In several cell lines, however, MAPKAP kinase-2 is activated by sodium arsenite, heat shock, or osmotic stress and not by agonists that activate p42/p44MAPK. We have identified a MAPK-like enzyme that acts as a MAPKAP kinase-2 reactivating kinase (RK). RK is recognized by an antiserum raised against a Xenopus MAPK (Mpk2), which is most similar to HOG1 from S. cerevisiae. We also identified a RK kinase (RKK) on the basis of its ability to activate either RK or a GST-Mpk2 fusion protein. The RKK, RK, and MAPKAP kinase-2 constitute a new stress-activated signal transduction pathway in vertebrates that is distinct from the classical MAPK cascade.

Amino Acid Sequence↗