PubMed Health⌕ Search

Biomedical subjects

W Michalski

Publications and source records attributed to W Michalski.

At least 19 recordsLinked to original sources

Long-term results of a randomized trial comparing preoperative short-course radiotherapy with preoperative conventionally fractionated chemoradiation for rectal cancer.

BACKGROUND: Neoadjuvant chemoradiotherapy does not alter anal sphincter preservation or postoperative complications compared with short-course radiotherapy alone in patients with clinical stage T3 or T4 resectable rectal cancer. The aim of this study was to compare survival, local control and late toxicity in the two treatment groups. METHODS: The study randomized 312 patients to receive either preoperative irradiation (25 Gy in five fractions of 5 Gy) and surgery within 7 days or chemoradiation (50.4 Gy in 28 fractions of 1.8 Gy, bolus 5-fluorouracil and leucovorin) and surgery 4-6 weeks later. The median follow-up of living patients was 48 (range 31-69) months. RESULTS: Early radiation toxicity was higher in the chemoradiation group (18.2 versus 3.2 per cent; P < 0.001). The actuarial 4-year overall survival was 67.2 per cent in the short-course group and 66.2 per cent in the chemoradiation group (P = 0.960). Disease-free survival was 58.4 versus 55.6 per cent (P = 0.820), crude incidence of local recurrence was 9.0 versus 14.2 per cent (P = 0.170) and severe late toxicity was 10.1 versus 7.1 per cent (P = 0.360) respectively. CONCLUSION: Neoadjuvant chemoradiation did not increase survival, local control or late toxicity compared with short-course radiotherapy alone.

Chemotherapy, Adjuvant↗

Clinical significance of serum cytokine measurements in untreated colorectal cancer patients: soluble tumor necrosis factor receptor type I--an independent prognostic factor.

The aim of this study was to exploit the potential clinical use of circulating cytokine measurements in colorectal cancer (CRC) patients. The levels of cytokines and cytokine receptors were assessed by ELISA in the sera of 50 healthy volunteers and 157 patients with previously untreated CRC and then related to clinicopathological features and prognosis. All tumors were verified histologically as colorectal adenocarcinomas and staged according to TNM classification. The levels of circulating interleukin (IL)-6, IL-8, macrophage colony-stimulating factor (M-CSF) and interleukin 1 receptor antagonist (IL-1ra) significantly increased with the clinical stage of CRC, and the levels of IL-6, soluble tumor necrosis factor (sTNF) receptor type I (RI), soluble interleukin 2 receptor alpha and TNFalpha with tumor grade, while IL-6, IL-8, M-CSF, IL-1ra and sTNF RI levels significantly rose with bowel wall invasion. None of the cytokine or soluble cytokine receptor levels were influenced by age, gender and colon versus rectum localization. sTNF RI, IL-8, IL-6 and vascular endothelial growth factor measurements demonstrated the highest diagnostic sensitivity. sTNF RI was found elevated in the greatest percentage of all CRC patients, in the greatest proportion of stage I patients and presented the best diagnostic sensitivity. In addition, the sTNF RI level strongly correlated with tumor grade and invasion and proved to be an independent prognostic factor.

Adult↗

Sphincter preservation following preoperative radiotherapy for rectal cancer: report of a randomised trial comparing short-term radiotherapy vs. conventionally fractionated radiochemotherapy.

BACKGROUND AND PURPOSE: The aim was to verify whether preoperative conventionally fractionated chemoradiation offers an advantage in sphincter preservation in comparison with preoperative short-term irradiation. PATIENTS AND METHODS: Patients with resectable T3-4 rectal carcinoma without sphincters' infiltration and with a lesion accessible to digital rectal examination were randomised into: preoperative 5x5Gy short-term irradiation with subsequent total mesorectal excision (TME) performed within 7 days or chemoradiation to a total dose of 50.4Gy (1.8Gy per fraction) concomitantly with two courses of bolus 5-fluorouracil and leucovorin followed by TME after 4-6 weeks. Surgeons were obliged to base the type of operation on the tumour status at the time of surgery. RESULTS: Between 1999 and 2002, 316 patients from 19 institutions were enrolled. The sphincter preservation rate was 61% in the 5x5Gy arm and 58% in the radiochemotherapy arm, P = 0.57. The tumour was on average 1.9 cm smaller (P < 0.001) among patients treated with chemoradiation compared with short-term schedule. For patients who underwent sphincter-preserving procedure, the surgeons generally followed the rule of tailoring the resection according to tumour downsizing; the median distal bowel margin was identical (2 cm) for both randomised groups. However, in the chemoradiation group, five patients underwent abdominoperineal resection despite clinical complete response. CONCLUSIONS: Despite significant downsizing, chemoradiation did not result in increased sphincter preservation rate in comparison with short-term preoperative radiotherapy. The surgeons' decisions were subjective and based on pre-treatment tumour volume at least in clinical complete responders.

Adult↗

The effect of thyroid hormones on blood insulin level and metabolic parameters in diabetic rats.

The effect of exogenous thyroid hormones on blood insulin and metabolic parameters in diabetic rats was investigated. Three groups of rats were treated with streptozotocin (STZ; 50 mg/kg b.w., intravenously) and one group receiving only saline served as control. Beginning with the third day after STZ treatment, until the last day before decapitation, i.e. for 11 days, two groups of diabetic rats were treated with T3 (50 microg/kg b.w., i.p.) or T4 (250 microg/kg b.w., i.p.). After two weeks, STZ injected rats had lower body weight, hyperglycemia with a simultaneous drop in blood insulin and decrease of T3 and T4 concentrations in comparison to control animals. Liver glycogen content was also reduced, whereas serum lactate, free fatty acids, triglycerides and cholesterol were elevated. Exogenous thyroid hormones given to diabetic rats substantially attenuated hyperglycemia without any significant changes in blood insulin concentration. An additional reduction of body weight gain and depletion in liver glycogen stores were also observed. Thyroid hormones augmented serum lactate and cholesterol and had no beneficial effect on elevated free fatty acids and triglycerides. It can be concluded that in spite of partial restriction of hyperglycemia, thyroid hormones evoked several unfavourable changes strongly limiting their potential use in diabetes.

Animals↗

[The results of treatment of middle ear carcinoma with radiotherapy].

We have described results of treatment patients with an extremely rare disease--a middle ear carcinoma. Through 25 years we have treated 37 patients. We recommend surgical treatment immediately supplemented by radiotherapy--because of anatomical difficulties in gaining enough histological margins. The median of survival time was 7 months in the group of palliatively treated patients and 14 months in the group of radically treated patients. Three patients had following complications: a necrosis of retromandibular space and mandibular joint, a purulent otitis media and an osteoporosis of the temporal bone.

Adult↗

Experimental studies of vibratory trauma of Corti's organ. I: Electrophysiological measurements.

In the present-day environment, vibration concomitant with noise is most frequently observed, but even though it is regarded as only a weak, additional traumatic factor affecting the organ of hearing. This opinion is contrary to a number of reports on the damage of the hearing organ caused by vibration in workers of various branches of industry. As experiments on humans are rather difficult, the harmful effect of vibration is usually examined on laboratory animals. In the majority of studies dealing with this problem the presence of noise (purposely or casually) was found in most cases. The aim of this study was to determine the effect of isolated long-term whole-body vibration and vertical sinusoidal shaking (10 Hz frequency, 5 mm amplitude, and 2 g acceleration) on Corti's organ. The study was carried out on young guinea pigs of both sexes. Eighty four animals (30 control and 54 experimental) with Preyer's reflex and without otoscopically detectable changes were used. A group of 18 animals was subjected to vibration in noiseless shaking apparatus for 30, 90 and 180 days. After a one-month rest, cochlear microphonics were performed under urethane anaesthesia. Our modification of the phase-sensitive detection method was used. Cochlear microphonics at frequencies of 260 Hz, 500 Hz, 1 kHz and 2 kHz was recorded from the apex of the cochlea and for 4 kHz and 8 kHz from the region of the round window. As the cochlear microphonics values showed significant individual differences, all experimental samples were examined by means of non-parametric tests. The outcome of the study demonstrated a gradual but considerable cochlear microphonics voltage decrease in the range to 2 kHz. This result pointed to the generation of vibration-induced damage in outer hair cells of the fourth and third turnings of the cochlea in the guinea pigs under study.

Animals↗

Sequence analysis of the Hendra virus nucleoprotein gene: comparison with other members of the subfamily Paramyxovirinae.

The nucleoprotein (N) gene of Hendra virus (HeV), an unclassified member of subfamily Paramyxovirinae in the family Paramyxoviridae previously known as equine morbillivirus, was cloned and sequenced. The majority of the deduced amino acid sequence was further confirmed by direct sequencing of peptide fragments of the N protein derived from purified virions. The 3' untranslated sequence of the HeV N gene mRNA was 568 nt and was much longer than that observed in other Paramyxovirinae. The N protein was 532 amino acids in length with a molecular mass of 58.5 kDa. Although the HeV N protein had a slightly higher amino acid sequence identity to those of the genus Morbillivirus than to those of other Paramyxovirinae genera, the level of identity was much lower than that observed within the morbilliviruses. Our results indicated that HeV could not confidently be classified as a member of the genus Morbillivirus, Paramyxovirus or Rubulavirus and suggest that the virus be classified in a new genus within the Paramyxovirinae.

Amino Acid Sequence↗

Prophylactic cranial irradiation in limited stage small cell lung cancer: survival benefit in patients with favourable characteristics.

The value of prophylactic cranial irradiation (PCI) in the treatment of small cell lung cancer (SCLC) remains controversial. As part of a randomised study investigating the timing of chest irradiation (CI) with respect to combination chemotherapy, the effect of PCI was evaluated. Between 1981 and 1989, patients were randomised to initial chest irradiation ICI (99 patients) or 18 weeks delayed late chest irradiation LCI (100 patients). PCI was given to 157 patients. In the beginning, only ICI patients received PCI, but in October 1984 the strategy was changed so that all patients received PCI. Thus, the patients who did not receive PCI were randomly allocated. The PCI dose was 33 Gy/11 fractions (45 patients) and 25 Gy/11 fractions (112 patients). The 2-year CNS-recurrence rate (+/- standard error) was significantly lower in patients who received PCI, 16.3 +/- 4.1%, than in those who did not, 55.1 +/- 12.4% (p = 0.01). In contrast, the 2-year cause-specific survival was not significantly different, 24.9 +/- 3.6% and 16.9 +/- 6.2% (p = 0.31). The 2-year progression-free rates with or without PCI were 18.5 +/- 3.3% and 11.4 +/- 5.4%, respectively (p = 0.58). To test the hypothesis that a benefit from PCI would mainly be expected among the patients with the best prognosis, a multivariate regression analysis of prognostic factors was undertaken. Based on weight loss, performance status, serum sodium and age, the third of the patients with the best prognosis were identified. In that group of patients, the survival advantage from PCI was statistically significant, 35.5 +/- 7.2% versus 14.1 +/- 8.0%, P = 0.029. These results are currently being tested in a Danish multicentre trial where patients with a good prognosis are randomised either to receive PCI or not to receive PCI.

Adult↗

Intradermal and subcutaneous leiomyosarcoma: a clinicopathological and immunohistochemical study of 41 cases.

Superficial leiomyosarcomas are rare tumours. The lesions confined to the dermis, contrary to those involving the subcutis, have been reported to carry a favourable prognosis. A retrospective study of 41 consecutive cases of surgically treated intradermal and subcutaneous leiomyosarcomas was undertaken in order to determine the prognostic factors that may influence the survival of these patients. Seven tumours were predominantly intradermal and 34 involved the subcutaneous tissue. Fifty-four percent of the tumours were located in the lower extremities. All cases stained positively for smooth muscle antigen and 66% for desmin. The tumours were classified with regard to tumour grade I (low grade, 3%), II (intermediate, 12%), IIIA (high grade, 46%) and IIIB (high grade, 39%). In all patients, follow-up information was available. Mean follow-up time was 5 years. The patients with intradermal tumours were all alive without signs of recurrence, whereas 14 of those with leiomyosarcomas involving the subcutis have died with pulmonary metastases. Our study confirms that "pure" intradermal leiomyosarcomas independent of tumour grade behave in a benign fashion, probably due to small tumour size. Tumour size > or = 5 cm, deep localization with fascia involvement, and high malignancy grade (IIIB) were found to deteriorate survival based on a univariate analysis. However, in a multivariate analysis only tumour size was found to be an independent prognostic factor.

Adult↗

Risk factors for central nervous system involvement in non-Hodgkins-lymphoma--a multivariate analysis.

A consecutive cohort of patients with NHL was examined to identify the factors predictive of CNS-involvement with Cox's proportional hazards model in a multivariate analysis. Twenty-seven cases of CNS-involvement were found among 498 patients with NHL. Only 3 of 96 patients with low-grade lymphomas had CNS involvement, all occurring after transformation into high-grade lymphoma. In univariate analysis of 402 patients with intermediate or high-grade lymphoma, lymphoblastic histology (including Burkitt's lymphoma), age <35 years, B-symptoms, stage IV disease, testis involvement and bone marrow involvement were found to be statistically significant risk factors. Lymphoblastic histology was found to be strongly correlated to age younger than 35 years. In the multivariate analysis only lymphoblastic histology, stage IV disease and B-symptoms were found to be significantly associated with CNS involvement. It is concluded that CNS prophylaxis should be considered in all patients with lymphoblastic histology and in patients with stage IV B lymphomas other than those of low-grade types.

Actuarial Analysis↗

[Experimental laser stapedectomy. Scanning electron microscopy studies].

The results of experimental tests performed upon 16 human stapes taken from cadavers were presented. The aim of the experiment was to define optimal parameters of laser stapedotomy. The less harmful range of argon laser energy for making the hole 0.6 mm diameter in the stape footplate was determined. There were two zones of tissue damage around the footplate's hole seen in scanning microscope. The internal area was made of carbonized tissue. The osseous tissue of the external zone had cavernous-cystic structure and lamellar stratification.

Culture Techniques↗