A novel neurotropic microsporidium from the swamp guppy Micropoecilia picta from Grenada, West Indies.

A novel microsporidium was observed in wild swamp guppies Micropoecilia picta from Levera Pond within Levera National Park Grenada, West Indies. Initial observations indicated similarity with Pseudoloma neurophilia, an important pathogen in zebrafish Danio rerio. P. neurophilia exhibit broad host specifity, including members of the family Poecillidae, and both parasites infect the central nervous system. However, spore morphology and molecular phylogeny based on rDNA showed that the swamp guppy microsporidium (SGM) is distinct from P. neurophilia and related microsporidia (Microsporidium cerebralis and M. luceopercae). Spores of the SGM were smaller than others in the clade (3.6 µm long). Differences were also noted in histology; the SGM formed large aggregates of spores within neural tissues along with a high incidence of numerous smaller aggregates and single spores within the surface tissue along the ventricular spaces that extended submeninx, whereas P. neurophilia and M. cerebralis infect deep into the neuropile and cause associated lesions. Analysis of small subunit ribosomal DNA sequences showed that the SGM was <93% similar to these related microsporidia. Nevertheless, one of 2 commonly used PCR tests for P. neurophilia cross reacted with tissues infected with SGM. These data suggest that there could be other related microsporidia capable of infecting zebrafish and other laboratory fishes that are not being detected by these highly specific assays. Consequently, exclusive use of these PCR tests may not accurately diagnose other related microsporidia infecting animals in laboratory and ornamental fish facilities.

[Peripheral arterial occlusive disease as predictor of high atherosclerotic burden]. / Periphere arterielle Verschlusskrankheit als Prädiktor einer hohen Atheroskleroselast.

Atherosclerosis is a disease which affects the whole arterial vascular tree. In particular patients with peripheral arterial occlusive disease (PAOD) often suffer from additional atherosclerotic manifestations in other vascular territories. This has a direct impact on cardiovascular prognosis. Atherosclerosis is an inflammatory disease. A high inflammatory burden is associated with polyvascular atherosclerosis and also with the occurrence of cardiovascular events. Control of cardiovascular risk factors is crucial for the treatment of patients with polyvascular atherosclerosis. In addition, anticoagulation treatment is very important in patients with atherosclerosis. Moreover, exercise training is an important treatment option in PAOD patients not only to improve walking distance but also for multiple additional positive effects. So far the role of anti-inflammatory treatment is not clear and must be further elaborated by future clinical research.

Intraperitoneal injection of sodium pentobarbital has the potential to elicit pain in adult rats (Rattus norvegicus).

An effective and pain-free killing method is required to achieve the goal of euthanasia, a "good death". Overdose of sodium pentobarbital (PB) by intraperitoneal (IP) injection is a widely accepted technique in laboratory rats, but questions remain regarding pain associated with administration. As PB rapidly causes sedation and loss of consciousness, most studies have relied on indirect evidence of pain. The objective of this study was to assess pain associated with IP PB using an appropriate vehicle control. Adult male and female Sprague Dawley (SD) and female Wistar rats (N = 84) were block randomised by sex and strain to receive one of three treatments: 1) 800 mg/kg PB (pH 11), 2) saline or 3) vehicle controls (pH 11 or 12.5). Behavior (Rat Grimace Scale (RGS), writhing, back arching) was evaluated at baseline, before loss of righting reflex (LORR, PB group), and at 80s, 151s and 10 min post-injection (PI; saline and vehicle control groups). In the PB group, mean time to LORR was 78 ± 7.9 seconds. In the vehicle control groups, RGS scores were increased at 151s PI (SD: p = 0.0002, 95%CI 0.73 to 0.20) from baseline, as was relative frequency of writhing (SD: p < 0.0001; Wistar; p = 0.0004). RGS scores remained elevated 10 mins PI (SD: p = 0.0005, 95%CI 0.71 to 0.18; Wistar: p = 0.0234, 95%CI 0.91 to 0.07) but the relative frequency of writhing did not (p > 0.999). The RGS scores and the relative frequency of writhing remained low in the PB and saline groups (p > 0.05). These results show that, vehicle controls for IP PB result in signs associated with pain, pain may not be experienced following IP PB when LORR occurs quickly, and that the effects of PB limit behavioral pain assessments.

Forced-air pre-warming prevents peri-anaesthetic hypothermia and shortens recovery in adult rats.

General anaesthesia disrupts thermoregulation in mammals, which can cause hypothermia. Decreases in core body temperature of 1℃ cause significant postoperative complications in humans, and peri-anaesthetic hypothermia in mice increases data variability, which can potentially increase animal use. In rats, the impact of different temperature management strategies on the incidence and severity of hypothermia, and the accuracy of different temperature measurement methods, is unknown. Eighteen adult male and female SD rats were block-randomized to one of three treatment groups: no-warming (NW), limited-warming (LW, heat pad during anaesthesia), and pre-warming (PW, warm air exposure before anaesthesia, followed by heat pad). Anaesthesia (isoflurane) duration was for 40 min. Core body temperature (intra-abdominal telemetric temperature capsule) was recorded during anaesthesia and recovery. During anaesthesia, rectal, skin, and tail temperatures were also recorded. In the PW group, core temperature was maintained during anaesthesia and recovery. By contrast, the NW group was hypothermic (11% temperature decrease) during anaesthesia. The LW group showed a decrease in temperature during recovery. Recovery to sternal recumbency was significantly faster in the PW (125 [70-186] s, P = 0.0003) and the LW (188 [169-420] s, P = 0.04) groups than in the NW group (525 [229-652] s). Rectal temperature underestimated core temperature (bias -0.90℃, 95% limits of agreement -0.1 to 1.9℃). Skin and tail temperatures showed wide 95% limits of agreement, spanning 6 to 15℃, respectively. The novel strategy of PW was effective at maintaining core temperature during and after anaesthesia. Rectal temperature provided an acceptable proxy for core body temperature.

The relationship between the Rat Grimace Scale and mechanical hypersensitivity testing in three experimental pain models.

BACKGROUND: The assessment of facial expressions associated with pain has been used to evaluate pain in humans and has recently found application in non-human mammals. These so called 'grimace scales' have the potential to be developed into a widely accepted non-invasive method of measuring pain in laboratory rodents. Currently, common methodologies to assess pain rely on nociceptive tests that assess stimulus evoked withdrawal responses. These tests, however, are limited to the assessment of a reflexive response without an affective component. This study aimed to use the recently developed Rat Grimace Scale (RGS) and assess its relationship with a conventional nociceptive test (the application of von Frey filaments). METHODS: Fifty-two adult, male Wistar rats were randomized to one of five treatment groups: intraplantar carrageenan, intraplantar complete Freund's adjuvant (CFA), plantar incision, anaesthetic control and saline injection control. The RGS and response to mechanical hypersensitivity testing was evaluated at predetermined time points before and after treatment until withdrawal responses returned to baseline levels. RESULTS: The RGS score significantly increased in all pain models. The peak RGS score also coincided with the development of paw hypersensitivity. However, mechanical hypersensitivity persisted after RGS scores returned to baseline. CONCLUSION: This study confirms that the three pain models induce pain in rodents and showed that peak pain coincided with peak mechanical hypersensitivity. However, mechanical hypersensitivity remained once pain subsided, mimicking the human experience of CFA injection. These findings further our understanding of the roles of, and relationship between, these assays in the assessment of nociception and pain.

Percutaneous transluminal coronary angioplasty after thrombolytic therapy: a prospective controlled randomized trial.

In 162 patients with acute transmural myocardial infarction, combined intravenous and intracoronary thrombolytic therapy with streptokinase was initiated. In vessels that remained occluded, mechanical recanalization was performed with a 3F recanalization catheter (group I, n = 79) or a 4F Grüntzig balloon catheter (group II, n = 83). After reperfusion, intracoronary streptokinase was administered superselectively. After termination of streptokinase infusion, angioplasty was performed only in patients in group II. There was no difference between the groups in relation to sex, age, infarct location, creatine kinase levels and time between onset of symptoms and start of treatment. Initial coronary angiography showed an open vessel in 27 (34%) of 79 patients in group I and 21 (25%) of 83 patients in group II. The final reperfusion rate was 90% (71 of 79) in group I and 86% (71 of 83) in group II. Angioplasty was attempted in 69 of the 71 patients in group II with a success rate of 65% and an occlusion rate of 3%. During the hospital stay, reocclusion occurred in 14 (20%) of 71 patients in group I. After thrombolytic therapy, coronary luminal narrowing in group I was 75 +/- 17% in patients without and 87 +/- 6% in patients with reocclusion (p less than 0.05). In group II, reocclusion was found in 10 (14%) of 71 patients. After angioplasty, the degree of coronary stenosis in group II was reduced from 82 +/- 12 to 51 +/- 30% (p less than 0.001). Reocclusion was found in 3 (7%) of the 45 patients with successful angioplasty and in 7 (32%) of the 22 patients with unsuccessful angioplasty (p less than 0.01). Improvement in regional left ventricular function was observed only in patients from group II with anterior myocardial infarction. In conclusion, by combined medical and mechanical recanalization, the rate of coronary reperfusion can be increased and infarct time shortened, providing the possibility of full revascularization by angioplasty, with improvement of regional wall motion and reduction of the rate of reocclusion.

Blood volume following diuresis induced by furosemide.

Changes in blood volume were investigated following intravenous injection of a single dose of furosemide in 21 patients with pulmonary edema. In a subset of 10 patients in whom the blood urea nitrogen level was 11.4 +/- 2.2 mg/dl and the serum creatinine level was 1.3 +/- 0.1 mg/dl and in whom total urine output exceeded 1 liter over a four- to six-hour interval ("diuretic" group), no significant change in plasma or total blood volume was observed, nor were there any significant changes in hematocrit. In a "nondiuretic" group of 11 patients who had moderately decreased renal function (blood urea nitrogen level 59.3 +/- 13.0 mg/dl and serum creatinine level 2.3 +/- 0.3 mg/dl) and in whom total urine output was less than 1 liter over the four- to six-hour interval, there was a significant increase in blood volume with a concomitant decrease in hematocrit and hemoglobin levels. Furosemide-induced diuresis therefore did not deplete intravascular volume. To the contrary, actions of furosemide that were independent of its diuretic action were associated with an expansion of plasma volume in the absence of diuresis. This may be related to the venous capacitance effects of furosemide with lowering of venous resistance and, therefore, lowering of the capillary hydrostatic pressure. In addition, there was an increase in colloid osmotic pressure. Both mechanisms increase the effective oncotic pressure gradient, which favors reabsorption of extravascular (edema) fluid. It is concluded that intravascular volume was therefore replenished at a rate equal to or in excess of the volume removed by diuresis.

Echocardiographic control of Swan-Ganz catheters.

In 68 patients, subxiphoidal, percordial, and suprasternal echocardiography was used to trace the Swan-Ganz catheter during its passage to the pulmonary artery and to localize its position. The localization of the catheter could be exactly identified in 62 out of 68 patients in whom we managed to obtain a suprasternal echocardiogram. In one patient, the catheter was found (by chest x-ray film) in the left pulmonary artery (LPA) and was regarded to be in the right pulmonary artery according to suprasternal echocardiography. In two patients, the catheter could not be localized by suprasternal echocardiography although it was positioned in the LPA. In three patients, the catheters could not be advanced to the pulmonary circulation and were visualized within the right ventricular cavity by precordial and subxihpoid echocardiogarphy. Thus, echocardiography, particularly the suprasternal approach, has proven a safe, reliable, and easy way for position control of Swan-Ganz catheters.

Transthoracic electrical impedance during extracorporeal hemodialysis in acute respiratory failure ("Shocked Lung syndrome").

The alteration (delta Z0) of transthoracic electrical impedance (TEI) during extracorporeal hemodialysis (EHD) was investigated in two Groups of patients with acute renal and acute respiratory failure, that differed with respect to the severity of respiratory insufficiency. Group I had moderate respiratory failure (FiO2 0.31 +/- 0.10, PaO2 84 +/- 14 mmHg), and Group II had severe respiratory failure (FiO2 0.75 +/- 0.17, PaO2 77 +/- 14 mmHg). There was a significant correlation between increase in TEI (delta Z0) and decrease in body weight (delta BW) in each individual patient, but the slope of regression lines was remarkably flattened in Group II. In Group I, delta TEI was 1.9 +/- 0.9 omega, the calculated TEI for 500 gr decrease in BW (delta Z0-500 gr) was 0.59 +/- 0.21 omega, and a significant correlation existed between pooled data of delta Z0 and delta BW. In Group II TEI increased less significantly, delta TEI was 0.6 +/- 0.3 omega (P less than 0.001), delta Z0-500 gr was 0.26 +/- 0.27 omega (P less than 0.01), and there was no correlation between pooled data of delta Z0 and delta BW. Increase of TEI in Group II could be completely attributed to increase in hematocrit. It is concluded that patients of Group I with acute renal failure and moderate respiratory failure lost intrathoracic fluid during EHD, whereas patients of Group II with severe respiratory failure did not. TEI during EHD may serve as a test for detection of fixed fluid within the pulmonary interstitium indicating a poor prognosis of the acute respiratory failure.

Application of impedance cardiography in critical care medicine.

In spite of good correlations between cardiac output measurements by impedance and established invasive procedures (dye- and thermo-dilution) reported by numerous authors it is doubtful uptil now whether calculations of stroke volume according to the formula of Kubicek et al. (1974) can provide absolutely reliable results. The origin of the dz/dt curve and influencing factors of impedance wave have to be cleared up prior to the total acception of impedance cardiography as a reliable method for determining non-invasive stroke volume. This is true in spite of the agreement of all authors we know, that the reproducibility of the impedance cardiography values is as good as in dye or thermo-dilution measurements. However, for patient monitoring it is sometimes more important to assess the relative changes in stroke volume than to measure its absolute value. For long-term non-invasive monitoring of myocardial contractility in critically ill patients or after pharmacological interventions impedance cardiography may be recommended. Besides systolic time intervals, such as pre-ejection time and ventricular ejection time, three more reliable parameters can be derived from the first derivate of impedance wave. Impedance plethysmography has been shown as a reliable method to diagnose deep vein thrombosis and good correlations between impedance and strain-gauge plethysmography and phlebographic findings are reported. In addition fluid volume changes in the leg, venous capacity, venous outflow and arterial inflow may be determined by impedance plethysmography in a simple way. There is no doubt that alterations in the fluid content of biological tissue may measured by impedance technique. However, correlations between changes in the transthoracic impedance and fluid content of the thorax can be quantified only in a single subject which serves as its own control. Overall standardization is not possible. The reason for interindividual differences in the thoracic impedance at a given reduction of body water are due to anatomical differences, intrapulmonary air volume and pressure, location of the electrodes, electrical conductivity of the tissue and, above all, due to the position of the body. Therefore if transthoracic impedance is determined sequentially measurements must be performed with special attention to the position of the body to get reproducible results. Rapid infusion of colloids or blood transfusion may decrease transthoracic impedance due to intravascular volume expansion even at a net fluid lost during forced furosemide-induced diuresis or extracorporal hemodialysis.(ABSTRACT TRUNCATED AT 400 WORDS)

[Local fibrinolytic therapy of vascular occlusions in the pelvic-leg area and the upper extremity]. / Lokale Fibrinolysetherapie von Gefässverschlüssen im Becken-Bein-Bereich und der oberen Extremität.

Seventy-three patients with vascular occlusions in the pelvis or lower limbs and three patients with upper limb lesions were treated by local low dose fibrinolysin, with strict control of any possible bleeding tendencies. Adequate recanalisation was obtained in 56 patients (73.6%). In ten patients, the occlusion recurred while the patient was still in hospital. After four to six months, 37 of the 56 (67%) of the vessels were still patent. In 18 patients, peripheral emboli resulted in some deterioration, but in 15 of these cases this could be treated successfully by operation. The methods and indications of local fibrinolysis therapy and the problems associated with it are discussed.

Balloon coronary angioplasty in patients with acute myocardial infarction.

After successful thrombolysis, approximately 75% of all patients will have significant coronary stenosis, which can be dilated by means of percutaneous transluminal balloon angioplasty (PTCA). In a randomized control study, 95 of our patients (Group I) had thrombolysis alone, whereas 95 others (Group II) had thrombolysis and PTCA. Both groups were comparable with respect to age, sex, infarct location, and maximal creatine kinase (CK) value. The clinical outcome during the hospital phase was better in Group II, which had a reocclusion rate of 13%, a reinfarction rate of 5%, a lethal reinfarction rate of 2%, and a cardiac death rate of 7%, compared with respective rates of 20%, 13%, 7%, and 13% in Group I. Furthermore, in Group I, residual coronary stenosis immediately after thrombolysis (75% +/- 20%) did not improve significantly until the end of the hospital phase, when it decreased to 69% +/- 21%. In Group II, stenosis (78% +/- 16%) was improved by PTCA to 33% +/- 21%, and this improvement remained constant during the hospital phase (30% +/- 26%). In Group-II patients who had an unsuccessful PTCA, stenosis was approximately the same before dilatation (83% +/- 12%), after dilatation (80% +/- 17%), and at the control study (83% +/- 17%). The end-diastolic, end-systolic, and stroke volume indices, as well as the ejection fraction, also remained unchanged. In Group I, the number of pathologic wall segments (12.2 +/- 5.0) did not improve during the hospital phase (12.2 +/- 7.9), but in Group II, the improvement was significant (14.0 +/- 5.7 vs. 10.9 +/- 8.2) (p < 0.05). PTCA seems to improve the clinical outcome, reduce the infarction and mortality rates, and enhance myocardial perfusion and performance.

[Influence of diphenylhydantoine on delta sharp-waves in coma. A clinical contribution (author's transl)]. / Medikamentöse Beeinflussbarkeit steiler delta-Wellen im Koma Ein kasuistischer Beitrag.

A patient with severe drug intoxication developed the well known EEG stages, starting with burst suppression activity until the pattern with delta waves and sharp waves was reached. At this stage it was treated with diphenylhydantoine intravenously. During injection the sharp elements disappeared and the pattern of faster waves was established. Thus it may be concluded that the sharp wave delta pattern indicates activity similar to that seen in epilepsy and that such a pattern needs anticonvulsant therapy.

Supernormal conduction in the right bundle branch: lack of influence of autonomic blockade.

A programmed atrial stimulation at a driving rate of 100/min was performed in a 47-year-old woman with left bundle branch block. Supernormal conduction lasting 40 ms was revealed within the right bundle branch. After autonomic blockade (0.2 mg propranolol/kg body weight and 0.04 mg atropine/kg body weight) the position and duration of the supernormal conduction did not change. This suggests that the autonomic nervous system has no influence on the supernormal phase of conduction in the human intraventricular conduction system.

[The vessel-mechanics of the common carotid artery in arterial hypertension]. / Die Gefässmechanik der Arteria carotis communis bei arterieller Hypertonie

The pressure-diameter relationship of the intact common carotid artery was studied in each of 36 normotensive and hypertensive patients of the same age. The diameter and its changes by pulse pressure were measured using an ultrasound echo-ranging device. The arterial blood pressure simultaneously was determined by the auscultatory method...

[Transcutaneous measurements of age conditioned changes in the elasticity of the human common carotid artery]. / Transkutane Messung altersbedingter Veränderungen der Gefässelastizität der Arteria carotis communis des Menschen

Measurements of common carotid arterial wall properties were done in a group of 36 test persons who were clinically free of arteriosclerosis obliterans. The patients were divided into three groups according to the age: 18-33, 36-52 and 56-72 years. Diameter and changes in diameter were measured using an ultrasonic echo-tracking system. Arterial pulse pressure simultaneously was determined by the auscultatory method. The deduced parameters of visco-elastic arterial wall property as distensibility, volume-eleastic modulus and pulse wave velocity indicate that arteries become stiffer with the age. The volume-elastic-modulus specially shows a numerical increase of 100% according to the age. An interpretation based on morphological investigations as well as the possibility using non-invasive methods to recognize an early manifestation of arteriosclerosis are discussed.