Biomedical subjects

K Wild

Publications and source records attributed to K Wild.

At least 19 recordsLinked to original sources

PubMed1997

Ultrasonographic examination of the abomasum of 50 cows.

The purpose of this study was to determine the position, appearance and dimensions of the abomasum of 50 healthy cows by ultrasonography. The ventral abdominal region caudal to the xiphoid process was examined with a 3.5 MHz linear transducer. The abomasum could be visualised from both sides and from the ventral midline of 47 of the cows. The abomasum could be clearly differentiated from adjacent organs because of its contents, which appeared as a heterogeneous, moderately echogenic structure with echogenic stippling. However, the wall of the abomasum appeared, if at all, as a narrow echogenic line. Parts of the abomasal folds were visible occasionally as echogenic structures within the abomasum. Slow movement of the feed in the abomasum was also often visualised. The pylorus was positively identified in only one cow. The cranial margin of the abomasum was situated up to 15 cm caudal to the xiphoid process. The abomasum was between 7.4 and 42.9 cm long, and its maximal extent, measured from the ventral midline to the left, was from 5.0 to 26.0 cm in the cranial region and from 5.0 to 16.0 cm in the caudal region. From the ventral midline to the right, it was from 5.0 to 33.0 cm in the cranial region and from 28.0 to 36.0 cm in the caudal region. The minimal dorsoventral dimension of the abomasum ranged from 0.7 to 7.2 cm, and its maximal dorsoventral dimension ranged from 3.6 to 11.1 cm.

Abomasum↗

PubMed1997

Effects of desflurane and isoflurane on systemic vascular resistance during hypothermic cardiopulmonary bypass.

OBJECTIVE: The objective of this study was to examine the dose-related effects of desflurane and isoflurane on systemic vascular resistance during hypothermic cardiopulmonary bypass. DESIGN: Randomized, prospective trial. SETTING: University hospital. PARTICIPANTS: Sixty consenting patients, 65 years of age or older, scheduled for elective coronary artery surgery. INTERVENTIONS: Patients were randomly allocated to one of five groups to receive 0.5 or 1.0 minimum alveolar concentration (MAC) (exhaust gas concentration) desflurane or 0.5 or 1.0 MAC isoflurane during hypothermic (32 degrees to 33 degrees C) nonpulsatile cardiopulmonary bypass or to a control group that did not receive any anesthetic agent. Systemic vascular resistance index was recorded at baseline, every 2 minutes for the first 10 minutes during initial administration and every 5 minutes for another 15 minutes during maintenance of anesthesia. MEASUREMENTS AND MAIN RESULTS: In patients receiving 0.5 MAC desflurane and isoflurane, there were significant differences in systemic vascular resistance index only at 20 and 25 minutes compared with control values. In the desflurane 1.0 MAC group, significant decreases were observed at 15, 20, and 25 minutes compared with controls. In the 1 MAC isoflurane group, the 10-, 15-, 20-, and 25-minute value differed significantly from the control. There were significant decreases in systemic vascular resistance index in the 1.0 MAC groups at 20 and 25 minutes compared with 0.5 MAC values, as well. CONCLUSIONS: Equi-MAC concentrations of desflurane and isoflurane had similar effects on systemic vascular resistance; 0.5 MAC maintained systemic vascular resistance; 1.0 MAC decreased systemic vascular resistance during hypothermic cardiopulmonary bypass.

Aged↗

PubMed1996

Dual action of a carbohydrate epitope on afferent and efferent axons in cortical development.

During development of the mammalian cerebral cortex, ingrowing afferents from the thalamus take a path that is different from that of axons leaving the cortical plate. Thalamic axons arrive at the cortex at the time before their target cells of layer 4 are generated in the ventricular zone, but they invade the cortex only shortly before these cells have migrated to their final position in the cortex. Growth-promoting molecules are up-regulated in the developing cortical plate during this period. To identify such molecules, we have generated monoclonal antibodies against membrane preparations from rat postnatal cortex. In Western blots, one antibody (mAb 10) recognized a carbohydrate epitope of a glycoprotein with an apparent molecular weight extending from 180 to 370 kDa. Immunohistochemical staining revealed that the staining pattern of mAb 10 at embryonic stages delineates the pathway of thalamocortical axons, with only very faint labeling of the corticofugal pathway. In vitro assays in combination with time-lapse imaging indicated that mAb 10 has opposite effects on the growth of thalamic and cortical axons. The growth speed and axonal elongation of thalamic fibers on postnatal cortical membranes preincubated with mAb 10 was reduced compared with untreated cortical membranes. In contrast, cortical axons grew faster and stopped their growth less frequently after addition of mAb 10 to a cortical membrane substrate. Taken together, these results suggest that a carbohydrate moiety of a membrane-associated glycoprotein plays a role in the segregation of afferent and efferent cortical axons in the white matter. Moreover, the epitope recognized by mAb 10 might also contribute to regulation of the timing of the thalamocortical innervation at later developmental stages.

Aging↗

PubMed1996

Brain activation during script event processing.

Regional cerebral blood flow was measured with positron emission tomography in seven normal volunteers while they performed various script event verification tasks. The left frontal lobe, left anterior cingulate and the anterior part of the left superior temporal gyrus were more activated in the script event membership and action categorization conditions, whereas the right frontal lobe, left superior temporal gyrus and the middle temporal gyrus bilaterally were more activated in the script event temporal order verification condition. These results indicate that the temporal ordering of script events and determining whether an event belongs to a particular script or action category are processed by distinctive distributed neuronal networks.

Adult↗

PubMed1996

[Serum fluoride concentrations and exocrine kidney function with sevoflurane and enflurane. An open, randomized, comparative phase III study of patients with healthy kidneys].

UNLABELLED: Sevoflurane is a "new" volatile inhaled anaesthetic. Owing to its lower blood-gas solubility coefficient, emergence from anaesthesia is faster with sevoflurane than with isoflurane, enflurane, or halothane. Sevoflurane undergoes metabolic biodegradation, releasing inorganic fluoride ions that could produce nephrotoxicity. In this study, we compared serum inorganic fluoride concentrations (IFCs) in patients receiving either sevoflurane or enflurane. Furthermore, indices of renal function were evaluated until the 3rd postoperative day. METHODS: Thirty patients with no history of renal or hepatic disease and with an anticipated duration of anaesthesia of at least 3 h were studied in an open, prospective, randomised clinical trial. Anaesthesia was induced with fentanyl, thiopentone, and vecuronium for facilitating endotracheal intubation. Anaesthesia was maintained with sevoflurane or enflurane, 60% nitrous oxide in oxygen, and additional doses of fentanyl. Blood samples for serum IFCs were obtained preoperatively and 2 and, if possible, 4 and 6 h after starting sevoflurane or enflurane, at the end of anaesthesia, and 1, 2, 4, 8, 12, 24, 48 and 72 h post-anaesthesia. Fluoride analysis was performed using an ion-selective electrode. Indices of renal function (serum sodium, osmolality, creatinine, urea, and uric acid, urine specific gravity, osmolality, and pH) were evaluated preoperatively, at the end of anaesthesia, and 24, 48, and 72 h post-anaesthesia. RESULTS: The duration of anaesthetic exposure was approximately 1.65 MAC-h for both inhaled anaesthetics. Peak serum IFCs were higher with sevoflurane (34.5 mumol/l) than with enflurane (19.4 mumol/l). Fluoride levels decreased more rapidly with sevoflurane: 24 h post-anaesthesia there was no difference between sevoflurane and enflurane (Fig. 1). The area under the curve (AUC) was greater with sevoflurane (688 mumol/l.h) than with enflurane (591 mumol/l.h). For both groups correlation coefficients were higher for MAC-h and AUC than for MAC-h and peak serum IFC (Figs. 2 and 3). Indices of renal function did not change in either group. DISCUSSION: In our study 1.69 MAC-h sevoflurane produced peak serum IFCs of 34.5 mumol/l. This is in accordance with the investigation of Frink et al. [4], who reported approximately 30 mumol/l after 1.4 MAC-h sevoflurane. Peak serum IFCs with sevoflurane were twice those with enflurane. Within the first 24 h post-anaesthesia, fluoride levels decreased more rapidly after sevoflurane. AUC may be more important than peak serum IFC in evaluating patients who are at risk for renal concentrating defects. In our study there was no evidence of renal dysfunction in either group.

Adult↗

PubMed1996

[Exposure of operating room personnel to anesthetic gases during ENT interventions].

During ENT surgical procedures under general anesthesia contamination of the operating room air through waste anesthetic gases seems unavoidable. A resulting chronic low-level exposure to anesthetic gases in subanesthetic concentrations (m1/m3 = ppm) may cause various negative health effects. The aim of this study was to quantify possible side effects on operating room personnel. By using a highly sensitive, direct reading instrument for determining contamination leakage from a patient's mouth and resulting concentrations in the breathing zone of the surgeon and anesthetist, levels of isoflurane and nitrous oxide were measured at 2-min intervals during 20 ENT surgical procedures performed under usual workplace conditions. Despite high concentrations of anesthetic at the mouth of each patient, personnel-related mean values remained under recommended threshold values (TLV) of 10 ppm isoflurane. A TLV of 100 ppm nitrous oxide was exceeded in 20% of the operations. Furthermore, a safe TLV for pregnant staff was 25 ppm nitrous oxide. This value was exceeded during nearly all operations (93%) for the group "surgeon". High leakages at the patient's mouth led to an undesirably high contamination of operating room personnel by nitrous oxide. Although threshold values were mostly not exceeded in available working conditions (i.e., adequate air conditioning and intubation cuff pressure control), present health and safety regulations concerning pregnant women showed that the values of nitrous oxide were still too high to allow such women to work safely in operating rooms during surgery. However, exposure to isoflurane was too slight to classify.

Adult↗

PubMed1996

Fluid therapy with Ringer's solution versus Haemaccel following coronary artery bypass surgery.

BACKGROUND: Crystalloid and colloid infusion can be used in volume therapy following heart surgery. In this prospective, randomised study we compared Ringer's solution (group R) to Haemaccel (group H) following coronary artery bypass grafting. METHODS: A stringent protocol for adjusting the infusion rate was used. Haemodynamic parameters and pulmonary function were evaluated as well as chest tube drainage. The double-indicator dilution method was used to measure total blood volume index (TBVI), intrathoracic blood volume index (ITB-VI) and extravascular lung water index (EVLWI). RESULTS: Haemodynamic stability was achieved in both groups throughout the study period, as judged from mean arterial pressure, central venous pressure, pulmonary capillary wedge pressure, and cardiac index. However, the total volume infused was significantly higher in group R. TBVI and ITBV were higher in group H, although only significant at 8 h for TBVI. Pulmonary function was similar in both groups. There was no significant difference in EVLWI, pulmonary shunt fraction, and time on mechanical ventilation. Likewise, chest tube drainage was not significantly different in both groups. CONCLUSION: We conclude that volume therapy with Haemaccel following heart surgery requires less volume and achieves better filling of the circulation compared to Ringer's solution.

Aged↗

PubMed1996

[Experiences and results in management of mandibular fractures with the modified Krenkel lag screw--a retrospective study].

The stable osteosynthesis of mandibular fractures with the modified lag screw (Krenkel) has proven superior to conventional lag screws in theoretical models and clinical use. Compared to osteosynthesis with plate systems, the lag screw technique is more difficult to learn for the unexperienced, but the reduction of fragments under compression with a lag screw and the stabilisation of lower jaw rotation with an additional short miniplate in our experience has proven successful in clinical use.

Adolescent↗

PubMed1996

Use and safety of a new repetitive transcranial magnetic stimulator.

In order to test a new repetitive transcranial magnetic stimulator, the Dantec MagPro, we administered transcranial magnetic stimulation (TMS) at 1 Hz and 125% of motor threshold for an average of 204 s (until the coil temperature reached 40 degrees C) and 20 Hz stimulation at 100% of motor threshold for 2 s every minute for 10 min, on different days to 10 healthy volunteers. We stimulated 6 scalp positions (primary motor area (M1) and sites 5 cm anterior and posterior on each hemisphere) with an 8-shaped coil. We tested immediate and delayed memory, verbal fluency, prolactin levels and EEG at the beginning of the study and after stimulation on each day. No abnormalities were found. Motor evoked potentials evoked with 1 Hz stimulation diminished progressively in amplitude, and 1 Hz stimulation of M1 caused inhibition lasting at least 1 min in 3 of 4 subjects who were tested with 0.1 Hz stimulation before and after the 1 Hz stimulation period. This did not occur with 20 Hz stimulation. Finger tapping frequency was tested at the beginning of the study and after TMS at each scalp site. Finger tapping rate data from 6 additional subjects who were stimulated in an identical fashion with a different stimulator were also analyzed. There was an increase in tapping rate after TMS which was independent of scalp site. This was most pronounced with 1 Hz stimulation at 125% of threshold and reached statistical significance in the hand contralateral to the stimulation. The results of this study indicate that rTMS with the MagPro stimulator is safe at specific combinations of intensity, frequency and train duration.

Adult↗

PubMed1995

Cell-specific expression of the alpha 9 n-ACh receptor subunit in auditory hair cells revealed by single-cell RT-PCR.

Single-cell reverse transcription polymerase chain reaction was carried out in three different cell types from the organ of Corti of the four-day old rat. For this purpose, pieces of the organ of Corti were mounted under a differential-interference contrast video microscope. Two different mounting configurations were used to allow imaging of cells from two almost orthogonal angles. This method afforded unequivocal recognition of various cell types in the vital tissue, and extraction of nucleus and cytoplasm of specified individual cells with a patch pipette. Messenger RNA encoding the alpha 9 acetylcholine (ACh) receptor subunit was detected and sequenced from individual outer hair cells and inner hair cells, but was not found in Deiters' cells. The identical Deiters' cells were positive for a P2x receptor subunit. This indicates cell-specific expression of the alpha 9 subunit in inner hair cells and outer hair cells and supports the hypothesis that this subunit contributes to calcium (Ca2+) permeable ionotropic ACh receptors (ACh-R). ACh-dependent Ca2+ concentration increase has been observed in both outer hair cells and inner hair cells.

Animals↗

PubMed1995

Ultrasonographic findings in 11 cows with a hepatic abscess.

The livers of 11 cows with a hepatic abscess were examined ultrasonographically. An abscess was observed in only one intercostal space in three cows, in two spaces in five, in three spaces in two, and in four adjacent intercostal spaces in one cow. In three cows the abscess was imaged in the caudodorsal aspect of the liver in the 11th and 12th intercostal space, in five cows the abscess was visible in the central part of the liver in the ninth and 10th intercostal space and in the three other cows the abscess was observed in the cranioventral region of the liver in the sixth, seventh and eighth intercostal spaces. The abscess had a distinct and well developed capsule in nine cows. The content of the abscess was echogenic in six cows, anechoic in two, and echogenic with hyperechoic foci in three. In four cows, the content of the abscess was partitioned by echogenic septa. In one cow, the echogenic content of the abscess was surrounded by a narrow anechoic rim of fluid. The diameter of the abscess was 5 to 10 cm in four cows, 11 to 15 cm in four, and more than 15 cm in three. In every case the diagnosis was confirmed by centesis and aspiration of the abscess which yielded pus. Ten of the cows were slaughtered after being examined and the ultrasonographic findings were confirmed. In addition, 10 of the cows had other lesions which included traumatic reticuloperitonitis, abscessation of the reticulum, thrombosis of the caudal vena cava, bronchopneumonia with abscessation, reticulo-omasal stenosis, ascites and suppurative omental bursitis.

Animals↗

PubMed1995

The three-dimensional structure of thymidine kinase from herpes simplex virus type 1.

Recombinant thymidine kinase from Herpes simplex virus type 1 (ATP:thymidine 5'-phosphotransferase; EC 2.7.1.21), an enzyme of therapeutic importance, was purified and crystallized in an N-terminally truncated but still fully active form. The three-dimensional structure was solved by X-ray diffraction analysis at 3.0 A resolution using isomorphous replacement. The chain fold is presented together with the bound substrates thymidine and ATP. Three chain segments at the surface could not be located. The chain fold, the location of the substrates and presumbly also the catalytic mechanism resemble the well-known adenylate kinases.

Amino Acid Sequence↗

PubMed1995

[Rates of awakening, circulatory parameters and side-effects with sevoflurane and enflurane. An open, randomized, comparative phase III study].

OBJECTIVE: Sevoflurane is a "new" volatile inhaled anaesthetic currently undergoing phase III clinical trials in Europe and USA. Owing to the low blood solubility, rapid induction of anaesthesia and emergence from anaesthesia would be expected. In this study, we compared emergence times and haemodynamics in patients receiving either sevoflurane or enflurane. Furthermore, all adverse experiences were recorded, and the relationship to the drug administered was rated. METHODS: Thirty ASA physical status I and II patients were studied in an open, prospective and randomised clinical trial. Anaesthesia was induced with fentanyl, thiopentone and vecuronium for facilitating endotracheal intubation. Anaesthesia was maintained with sevoflurane or enflurane, 60% nitrous oxide in oxygen and additional doses of fentanyl (1-2 micrograms/kg/h). ECG, blood pressure (non-invasive), inspiratory and end-tidal concentrations of sevoflurane or enflurane were monitored continuously. At the end of surgery, administration of sevoflurane or enflurane and nitrous oxide stopped without tapering and emergence times were recorded. All adverse experiences which occurred until the third postoperative day were recorded and the relationship to the inhaled anaesthetic was rated as "none", "unlikely", "possible", "probable" or "highly probable". RESULTS: With the exception of the end-tidal concentration at the end of surgery and the mean inspiratory and end-tidal concentrations, which were higher for sevoflurane, the two patient groups were comparable. Pulmonary elimination was significantly faster and emergence time was significantly shorter (5 vs. 9 minutes) with sevoflurane. Emergence time did not correlate with the duration of anaesthetic exposure (MAC hours) for sevoflurane. There was no difference in the time courses of heart rate and mean arterial blood pressure between sevoflurane and enflurane. No adverse experiences with a "probable" or "highly probable" relationship to the inhaled anaesthetic were observed. CONCLUSION: Emergence time after inhalation anaesthesia depends on (alveolar) ventilation, blood-gas solubility coefficient and, at least for enflurane and isoflurane, on the dose applied (MAC hours). There is no positive correlation between emergence time and dose applied for sevoflurane. Due to the lower blood-gas solubility coefficient (0.6-0.7 for sevoflurane vs. 1.8 for enflurane) pulmonary elimination is faster and emergence time is shorter with sevoflurane. Supplementing inhalation anaesthesia with fentanyl, there is no difference in the time courses of heart rate and mean arterial blood pressure between sevoflurane and enflurane.

Adult↗

PubMed1995

Should we estimate liver span in the right mid-clavicular line or the midline?

OBJECTIVE: Comparison was made between the accuracy of repeated measurements of liver projection below the costal margin in the right mid-clavicular line (RMCL) and in the midline (ML). METHODOLOGY: Clinical measurement of liver span was studied in 34 children under 5 years of age by five members of junior ward staff. Three patients were followed longitudinally by the same observers. RESULTS: The coefficient of reliability between different observers for measurement in the RMCL was 13 mm but for that in the ML was 7 mm. Estimates of liver size in the RMCL were particularly inaccurate when examining larger livers. CONCLUSION: More reliable sequential estimates of liver size are likely to be obtained using measurements both in the midline and in a well-defined and agreed point below the right costal margin.

Age Factors↗

PubMed1995

[Schwannoma of the gastric wall].

Clinical and ultrasound examination showed a tumor adjacent to the posterior gastric wall in two patients with noncharacteristic upper abdominal pain. The structure of the at least fist-size masses was partly solid, partly cystic and on palpation appeared soft and spongy with a smooth surface. Colour ultrasound showed a high vascularity. All these factors were confirmed by computerized tomography. History as well as clinical and ultrasound examination suggested the diagnosis of schwannoma and this was confirmed by histopathology following laparotomy.

Aged↗

PubMed1992

Inguinal herniotomy in young infants.

Ninety-two consecutive infants aged up to 12 months underwent primary inguinal herniotomy over a 5-year period. All were treated in a district hospital paediatric surgical unit according to recommendations of the British Association of Paediatric Surgeons. After a mean follow-up of 45.8 months, one patient had a failed repair and four (4 per cent) a hernia recurrence. One infant developed a wound infection. Infantile hernia can be managed safely and efficiently in a district hospital.

Female↗

PubMed1992

Cell-mediated immunity and its glucocorticoid-sensitivity after clinical recovery from severe major depressive disorder.

This follow-up study investigated lymphocyte blastogenesis induced by concanavalin A, phytohemagglutinin A, and pokeweed mitogen and their sensitivity to in vitro dexamethasone administration in 12 patients clinically recovered from severe major depression. Although cortisol-levels at 4.00 p.m. decreased significantly after clinical remission, mitogen-driven lymphocyte proliferative responses were unchanged when assessed intra-individually. No impairment of in vitro glucocorticoid-sensitivity of lectin-induced lymphocyte blastogenesis could be observed in clinically recovered patients. The inhibitory potency of in vitro dexamethasone was found to be inversely correlated with in vivo adrenal cortical hormone levels. There were no correlations with age, weight, sex, antidepressant medication, severity or duration of depression. No differences from age- and sex-matched healthy individuals were found. These results indicate that reduced glucocorticoid receptor sensitivity occurs only during the acute depressive illness.

Adrenocorticotropic Hormone↗

PubMed1991

In vivo and in vitro effects of glucocorticoids on lymphocyte proliferation in depression.

Twelve severely depressed patients and 13 healthy controls were studied under baseline, metyrapone and metyrapone plus dexamethasone pretreated conditions. Lymphocyte proliferation data were obtained by concanavalin A, phytohaemagglutinin and pokeweed mitogen (PWM) stimulation. There was a decrease in PWM-induced B-cell proliferation and an increase in inhibition of spontaneous leucocyte proliferation by dexamethasone added in vitro following metyrapone administration in vivo, in healthy controls, which was not present in the depressed patients. These data support the concept of a decreased functional plasticity of the glucocorticoid receptor in depression also at the cellular level.

Adolescent↗