Biomedical subjects

M Szymański

Publications and source records attributed to M Szymański.

At least 19 recordsLinked to original sources

PubMed2006

Experimental study on heat transmission to the vestibule during CO2 laser use in revision stapes surgery.

We studied the transmission of heat to the vestibule during revision stapes surgery with a piston in situ, using a CO2 laser, in an in vitro model. A type K thermocouple was placed around the medial end of stainless steel and fluoroplastic wire pistons in a 'vestibule' filled with saline. The effect of laser hits on fluoroplastic wire and stainless steel stapes prostheses was investigated. The effect of introducing a vein graft to seal the stapedotomy was also examined. Greater temperature rises occurred with stainless steel than with fluoroplastic wire pistons. The addition of the vein graft reduced heat transmission. Application of the CO2 laser to fluoroplastic wire pistons, using the power settings suggested by the manufacturer, is not likely to damage the inner-ear structures. Application of 6 W laser energy to stainless steel pistons can potentially disturb the inner-ear function.

Hot Temperature↗

PubMed2006

Regulatory RNAs in mammals.

Recent years have brought a dramatic change in our understanding of the role of ribonucleic acids (RNAs) within the cell. In addition to the already well-known classes of RNAs that take part in the transmission of genetic information from DNA to proteins, a new highly heterogeneous group of RNA molecules has emerged. The regulatory nonprotein-coding RNAs (npcRNAs) have been shown to be involved in modulation of gene expression on both the transcriptional and post-transcriptional level. They participate in mechanisms of chromatin modification, regulation of transcription factor activity, and influencing mRNA stability, processing, and translation. npcRNAs are key factors in genetic imprinting, dosage compensation of X-chromosome-linked genes, and many processes of differentiation and development.

Animals↗

PubMed2001

[Detection of human papillomavirus type 16 and 18 in laryngeal cancer using PCR methods].

Human papillomavirus (HPV) is a small DNA virus. HPV is can be divided into two groups: mucosal and cutaneous. HPV have various oncogenic potential. The correlation between presence of high oncogenic type of HPV and carcinogenesis was confirmed in human anogenital tract and cervical carcinoma. The latest studies suggest HPV infection involvement in benign and malignant lesions of aerodigestive tract. The aim of our study was to determine the presence of the HPV genes E6/E7. The specimens were taken after total laryngectomy from 20 patients with squamous cell carcinoma. The fresh tissue specimens were frozen at -70 degrees C until DNA extraction and HPV detection. The presence of HPV DNA was assessed by polymerase chain reaction using specific primers for HPV 16 and 18 E6/E7. There were 7 (35%) HPV positive specimens in our group. 5 (25%) specimens were HPV 16 positive, 4 (20%) specimens were HPV-18 positive. In two cases HPV 16 and HPV 18 was present. The results suggest that high oncogenic types of HPV may play a role in pathogenesis of laryngeal carcinoma.

Adult↗

PubMed2001

[Concentrations of MMP-1, TIMP-1, MMP-1/TIMP-1 and I CTP complexes in follicular fluid as related to fertilization rate in women treated with in-vitro fertilization].

OBJECTIVES: Metalloproteinases and their inhibitors appear to control connective tissue remodelling during follicular rupture. The aim of the study was to establish if oocytes fertilisation rate after ovulation induction depends on the concentrations of MMP-1, its inhibitor TIMP-1, MMP-1/TIMP-1 complex and I CTP in follicular fluid (FF). MATERIAL AND METHODS: FF were collected from 37 infertile patients undergoing ovulation induction using either short or long protocol. FF was obtained 36 hours after administration of hCG (Pregnyl). The level of MMP-1, TIMP-1, MMP-1/TIMP-1 complex were measured using ELISA kits and I CTP, E2, FSH, LH, using RIA assay kits. RESULTS: Statistically significant (p < 0.05) difference was found in TIMP-1, E2, and FSH concentration, being higher in the group with more than 75% fertilisation rate: TIMP-1 728.8 + 100.1 ng/ml vs 666.3 + 94.5 ng/ml; E2 477.3 +/- 160.0 ng/ml vs 368.0 +/- 190.0 ng/ml and FSH 7.27 +/- 1.45 mIU/ml vs 6.24 +/- 1.6 mIU/ml. CONCLUSIONS: Statistically significant increase in TIMP-1 concentration observed among patients with fertilisation rate above 75% indicates an important role of this substance in ovulation process.

Adult↗

PubMed2001

Structure and functions of 5S rRNA.

The ribosome is a macromolecular assembly that is responsible for protein biosynthesis in all organisms. It is composed of two-subunit, ribonucleoprotein particles that translate the genetic material into an encoded polypeptides. The small subunit is the site of codon-anticodon interaction between the messenger RNA (mRNA) and transfer RNA (tRNA) substrates, and the large subunit catalyses peptide bond formation. The peptidyltransferase activity is fulfilled by 23S rRNA, which means that ribosome is a ribozyme. 5S rRNA is a conserved component of the large ribosomal subunit that is thought to enhance protein synthesis by stabilizing ribosome structure. This paper shortly summarises new results obtained on the structure and function of 5S rRNA.

Animals↗

PubMed2001

[Epistaxis: causes and management].

Evaluation of 265 patients treated in hospital due to nasal bleeding revealed that almost half of them suffered from hypertension and in about 30% of cases it was impossible to establish the cause of epistaxis. The most frequent way to stop the bleeding was anterior nasal packing and in case of failure posterior nasal packing together with anterior one. Posterior nasal packing with Foley's catheter is relatively simple and effective procedure. Introduction of superselective embolization of maxillary artery and dermoplasty in Rendu-Osler disease was very helpful.

Adolescent↗

PubMed2001

Short- and long-term results of stapedectomy in children.

Otosclerosis in children and teenagers is very uncommon. Typical otosclerosis presents as a slowly progressive conductive hearing loss and tinnitus in the third to fourth decade of life. Stapedectomy is a well-established procedure for correction of conductive hearing loss in adult patients with otosclerosis. The aim of this work is to assess short- (6 months) and long-term (7 years) results after stapedectomy performed in 10 patients under 20 years of age. In 1 patient cochlear otosclerosis was diagnosed and in 1 patient incus anomaly was found during the operation. Pure tone audiograms obtained 6 months after stapedectomy showed air-bone gap closure to 10 dB in 6 patients, to 15 dB in 8 patients and in all patients to 20 dB. Average air conduction threshold improved by 26.5 dB and average bone conduction threshold by 5.9 dB. 7 years after stapedectomy air-bone gap was similar to the one measured 6 months postoperatively. Stapedectomy in children provides good and stable hearing results.

Adolescent↗

PubMed2001

[Complications of three methods of stapedectomy].

In a group of 270 partial stapedectomies performed by one surgeon using teflon-piston prosthesis it was assessed whether incidence of complications depended on sequence of surgical steps. In group I of 50 ears classical stapedectomy was performed: 1. removal of stapes superstructure, 2. making a hole in the footplate, 3. placing the prosthesis on the incus. In group II of 167 ears the hole in the footplate was made before removal of stapes arch. In group III of 53 ears: 1. the hole in the footplate, 2. placing the prosthesis on the incus, 3. removal of stapes arch, was performed. Total deafness had one patient of the whole group. No patient had perilymphatic fistula and facial nerve palsy. Floating footplate developed in 4 patients of group I, in one patient of group II and in none patient of group III. Subluxation of incus developed in 3 patients of group I, in 12 patients of group II and in none patient of group III. Comparison of three stapedectomy methods showed that making the hole in the footplate before removal of stapes arch prevents floating footplate and placing the prosthesis on the incus before removal of stapes arch prevents subluxation of the incus.

Adolescent↗

PubMed2000

5S ribosomal RNA.

Ribosomes have been visualized in electron micrographs in 1943 but 5S rRNA was discovered 20 years later. The next four decades witnessed big advances in our understanding of the ribosome using biochemical, genetic and low resolution structural approaches. During those times many experimental data accumulates also on 5S rRNA, but its precise function remains unknown. To understand the role of this RNA in ribosome a high-resolution structure is urgently needed. Because the ribosome is a dynamic machine, details on the interaction of 5S rRNA with proteins within entire ribosome are required. Big progress in the structural analysis of ribosome will stimulate further understanding of 5S rRNA.

Animals↗

PubMed2000

Minireview: analysis of rape seed napin structure and potential roles of the storage protein.

Structural and functional data on 2S albumins and particularly rape seed napins are reviewed and, based on the coordinates of the three-dimensional structure of napin-like albumin BnIb, are used to model different rape napins. Surprisingly, the modeled napins, despite great sequence homology, differ in tertiary arrangements of the polypeptide chains. It is proposed that these differences in 3D structures of the analyzed rape napins may reflect their functions, which may cover many other potential beneficial purposes besides simple storage.

2S Albumins, Plant↗

PubMed2000

An analysis of G-U base pair occurrence in eukaryotic 5S rRNAs.

The structure-function relationship in RNA molecules is a key to understanding of the expression of genetic information. Various types of RNA play crucial roles at almost every step of protein biosynthesis. In recent years, it has been shown that one of the most important structural elements in RNA is a wobble pair G-U. In this paper, we present for the first time an analysis of the distribution of G-U pairs in eukaryotic 5S ribosomal RNAs. Interestingly, the G-U pair in 5S rRNA species is predominantly found in two intrahelical regions of the stems I and V and at the junction of helix IV and loop A. The distribution of G-U pairs and the nature of adjacent bases suggests their possible role as a recognition site in interactions with other components of protein biosynthesis machinery.

Animals↗

PubMed2000

[Evaluation of cGMP plasma concentration in women in normal pregnancy and labor].

UNLABELLED: Aim of our study was evaluation of cGMP plasma concentration in women in course normal pregnancy and labour. The investigations were performed in Department of Obstetrics and Gynaecology Medical Academy in Bydgoszcz. Following groups of patients were examined. 1. 12 non-pregnant women 2. 59 women with normal pregnancy 3. 31 women at term with spontaneous uterus contractions. RESULTS: 1. low concentrations cGMP in plasma in non-pregnant women in course of menstruation cycle 2, low concentration cGMP in the first half of pregnancy--with gradual increase from 25 to 33 gestation week and with rapid increase in last 7 weeks of pregnancy, 3.--significant higher cGMP concentration at term in relation to values observed in early pregnancy and to the period between 28 and 37 weeks of gestation 4. significant higher cGMP plasma concentration in women in labour in relation to cGMP concentrations at term without uterus contractions.

Adult↗

PubMed2000

The new aspects of aminoacyl-tRNA synthetases.

Aminoacyl-tRNA synthetases (AARS) are essential proteins found in all living organisms. They form a diverse group of enzymes that ensure the fidelity of transfer of genetic information from the DNA into the protein. AARS catalyse the attachment of amino acids to transfer RNAs and thereby establish the rules of the genetic code by virtue of matching the nucleotide triplet of the anticodon with its cognate amino acid. Here we summarise the effects of recent studies on this interesting family of multifunctional enzymes.

Amino Acid Sequence↗

PubMed1999

[Evaluation of using Levovist in the differential diagnosis of ovarian tumors].

The research on applying Levovist was carried out in the Department of Obstetrics and Gynaecology of Medical Academy in Bydgoszcz, Poland, in the years 1997-1998. Out of 118 hospitalised patients with preliminary diagnosis: tu. hypogastrii, tu. adnexorum, tu. ovarii, cystis ovari, due to the suspicious ultrasound result, and/or decreased parameters of arterial blood flow (PI < 1.0; RI < 0.6) and or presence of abdominal fluid, 32 women were included in the study. The changes in the Doppler image under the influence of Levovist and their correlation with histologic features were analysed. The time span between injection of Levovist and the enhancement of the Doppler image was not characteristic for any tumor. However, it was observed, that the mean return time i.e. from the enhancement of the Doppler signal to the initial pattern, was considerably longer in carcinomas than in other ovarian tumours. No signal enhancement was observed in benign lesions.

Adolescent↗

PubMed1998

[Pregnancy and labor in patients with myopathy].

25 years old pregnant women with dysrtophia musculorum progresiva was observed in The Ludwik Rydygier Medical University in Bydgoszcz (Poland). Pre-term activity of uterus and diabetes gravidarum were complicated pregnancy. In 36 week of pregnancy forceps operation was make of obstetric indications and maternal myopathy.

Adult↗

PubMed1998

[Struma ovarii: rare ovarian neoplasm].

Authors of this research present 3 cases of struma ovarii diagnosed in postoperative histopathological examination in years 1994-1997. The first one was accidentally discovered during examination of a woman in menopausal period, the second was a case of 39-years old woman with hyperthyroidism and struma parenchymatoso-nodosa and the third was detected during examination of a young 21-years old woman with abdominal pain. In first two cases Doppler flowmetry revealed low RI and PI parameters (< 0.5 and < 0.7 respectively) in tumor structures.

Adult↗

PubMed1998

[Evaluation of ovarian tumor vascularization by means of intravaginal ultrasonography with color Doppler].

53 cases of ovarian tumors were diagnosed and operated in the Clinic of Obstetrics and Gynecology of Medical Academy in Bydgoszcz in years 1996-1997. Retrospective analysis of 58 results of ultrasonographic examination with color-Doppler estimated flows and histopathological diagnoses in cases of ovarian tumor was performed. On the ground of sonographically estimated morphology, presence or absence of vascularization and pulsation and resistance indices (PI and RI respectively) an attempt to discriminate benign and malignant tumors was made. Values of RI > 0.6 and PI > 1.0 in absence of morphologically suspicious features in ultrasonographic examination correlated with benign forms of ovarian tumors in histological examination.

Female↗

PubMed1997

Compilation of ribosomal 5S ribonucleic acid nucleotide sequences: eukaryotic 5S rRNAs.

5S Ribosomal RNA is the smallest RNA component of the ribosomes. Due to relatively simple isolation and sequencing procedures as well as a potential use of the sequence data in evolutionary analyses, the amount of known nucleotide sequences on both RNA and DNA levels was rapidly growing. In this paper we present the updated (March 1996) compilation of eukaryotic 5D rRNA and 5S rDNA sequences.

Animals↗