PubMed Health⌕ Search

Biomedical subjects

J Málek

Publications and source records attributed to J Málek.

17 recordsLinked to original sources
PubMed2003

Evidence for two types of low-energy charge transfer excitations in Sr2CuO3.

A comparative analysis of electron energy-loss spectroscopy (EELS) spectra for the 1D insulating cuprate Sr2CuO3 with transferred momentum q--> axially and radially to the chain axis allows one to elucidate the structure of the charge transfer gap in in-chain response. It is determined by the superposition of two types of excitations with different magnitudes of dispersion. The low-energy response with q--> radially to the chain direction, but yet within the plane of CuO4 plaquettes, exhibits also a dispersionless peak near 2 eV. The theoretical simulation of the EELS data using exact diagonalizations of an appropriate extended Hubbard Hamiltonian for relevant clusters requires the explicit consideration of low-lying oxygen 2p pi states within the CuO4 plaquette plane beyond the standard pd sigma extended Hubbard model widely used for cuprates with corner-shared CuO4 plaquettes.

Journal Article↗
PubMed2003

[Progress in surgical treatment may improve the quality of life in patients with breast surgery for malignant tumors].

Breast cancer surgery (BCS) is a common procedure performed in women. Chronic postmastectomy pain (PMP) has been reported in as many as 22-72 percent of patients. There are no published reports in Czech Republic. This study was performed to evaluate the prevalence and risk factors of PMP. An anonymous questionnaire was given to women after attending oncology departments in various hospitals during 3-month period. All 176 questionnaires have returned. The average age was 63.6 (SD 11.2) years, BMI 26.3 (SD 4.0). There was 23.6% of PMP prevalence in our group. The risk factors were younger age (below 60, p < 0.001, below 65, p < 0.01 resp.) and type of surgery (total mastectomy vs. tumour removal, p < 0.01). The prevalence of PMP in our study was significantly lower than in other studies. The age of our group was higher, than in other studies, but it does not explain the difference. We can hypothesise the reason is improved surgical technique.

Breast Neoplasms↗
PubMed2002

New type of anaesthesia with sevofluran improves surgical and post-surgical course of burns treatment (IGA 6116/2).

The objectives of this open-perspective clinical study were to test the effect of a new type of anaesthesia using sevofluran during surgical treatment of patients with burns, and to compare it with that of ketamin, at present the most frequently used anaesthetic. The study, conceived as a pilot study, was performed on 10 paediatric and 8 adult patients with 2nd degree burns covering between 7% and 35% of body surface. Owing to highly significant differences in parameters in favour of sevofluran, it was recommended by our ethical committee not to increase the number of patients. The parameters considered were ease of induction, undesirable effects, span of time before oral administration of liquids. Daily uptake of energy was measured for both types of anaesthetics in another group of 10 patients. In adult patients the two anaesthetics, ketamin versus sevofluran, differed in terms of incidence of unrest during surgery (ketamin 50% vs. sevofluran 0%, p < 0.05), time between end of surgery and return to full consciousness (11.3 min. vs. 2.7 min. p < 0.001), post-surgical inhibition (75% vs. 0%, p < 0.01) psychomimetic reactions after surgery (50% vs. 0%, p < 0.05), time until first intake of liquids (86.7 min. vs. 8.5 min, p < 0.001), and mobilisation (110.8 min. vs. 17 min., p < 0.001). In paedriatic patients, differences in speed of onset of anaesthesia (216 sec. vs. 66 sec., p < 0.001) and time until first uptake of liquids (75 min. vs. 22 min., p < 0.001) were statistically significant. Apart from problems associated with anesthesia, another considerable advantage of the new anaesthetic sevofluran was a significantly increased uptake of calories after use than was the case after ketamin (1645 kJ higher on the average, p < 0.05). Based on these results, sevofluran was introduced to burns surgery as a routine anaesthetic.

Adult↗
PubMed2002

[Infiltration of local anesthetics into the thyroid gland capsule for surgery and the postoperative period].

In a prospective randomized study the hypothesis was tested whether infiltration of the thyroid capsule by a local anaesthetic will reduce the haemodynamic response to surgical trauma, consumption of anaesthetics and opioids during surgery and will shorten the time of arousal. A total of 64 patients indicated for planned goitre surgery were divided at random into a control group (C, n = 32) and experimental group (LA, n = 32). The preoperative medication and anesthesia did not differ in the two groups. In group C into the thyroid capsule a maximum of 40 ml saline was administered, in LA the same volume of 0.5% trimecain. A highly significant difference was found (p < 0.001) in the incidence of hypertension during surgery (21 C vs. 5 LA) and the need of further pharmacological interventions (21 vs. 8). In the control group was a higher consumption (p < 0.95) of the opioid phentanyl (167.5 +/- 111 micrograms vs. 125 +/- 93.5 micrograms), a trend of longer arousal and the need to antagonize the effect of opioid (p < 0.1). The substitution of saline by a local anaesthetic for infiltration of the thyroid capsule is a safe and simple method leading to a reduction of cardiovascular complications during surgery.

Anesthesia, General↗
PubMed1999

[Adverse hemodynamic changes during laparoscopic cholecystectomy and their possible suppression with clonidine premedication. Comparison with intravenous and intramuscular premedication].

Laparoscopic cholecystectomies have adverse haemodynamic effects which limit their use in risk patients with heart disease. This applies in particular to significant hypertension. The etiology is analysed in detail in a review of the literature. The authors confirmed in their work involving 21 patients the incidence of these effects and tried to suppress them by premedication with clonidine (CATAPRESAN, Boehringer). 21 patients were given 0.15 mg clonidine in an infusion 15 minutes before operation and 21 patients 0.15 mg clonidine by the i.m. route 60-90 min. before operation. Standard anaesthesia was administered. A highly significant drop in the incidence of hypertension was recorded during operation for systolic pressure (p < 0.001) after both ways of administration, as well as of diastolic pressure (p < 0.01 for intravenous and p < 0.05 for intramuscular premedication). Premedication with intravenous clonidine can be recommended as a routine procedure before laparoscopic cholecystectomies.

Adrenergic alpha-Agonists↗
PubMed1997

Exposure to stress alters the effects of dynorphins in the hot plate test.

The analgesic effects of intracerebroventricularly (i.c.v.) administered dynorphin A(1-13) and its analog dynorphin A(1-10)amide using the hot plate test were studied in mice. Both dynorphins applied i.c.v. by the freehand method had an analgesic effect but no effect was seen when applied i.c.v. through an implanted cannula. Moreover, freehand i.c.v. injection of saline increased the time of immobility in the forced swimming test and glycaemia levels compared with intact mice. In contrast to the freehand injection, saline administration through an implanted cannula did not influence the immobility of animals in forced swimming test when compared with the intact controls. These results suggest that 1) the freehand method is very stressful procedure of administration which could influence the effects of dynorphins in the hot plate test and 2) dynorphins exert an analgesic effect in the hot plate test only when combined with a stressor (freehand i.c.v. injection).

Analgesics, Opioid↗
PubMed1996

Influence of dynorphin A (1-13) and dynorphin A (1-10) amide on stress-induced analgesia.

Dynorphin A (1-13) and its analog dynorphin A (1-10) amide were applied intracerebroventricularly in male ICR mice. Both dynorphins did not reveal any analgesic activity in tail-flick test under normal (non-stressed) conditions. However, in combination with stress (forced swimming or whole body vibration) both dynorphins prolonged tail-flick latencies when compared with stressed saline controls. Naloxone inhibited the effect of dynorphins in forced swimming test. Neither dynorphin A (1-13) nor dynorphin A (1-10) amide increased tail-flick latencies when combined with weak immobilization stress. Our results suggest that the analgesic effects of dynorphins are potentiated by strong stressors.

Analgesia↗