Biomedical subjects

M Nowak

Publications and source records attributed to M Nowak.

At least 37 records · Page 2Linked to original sources

PubMed2001

Online reference database of European Y-chromosomal short tandem repeat (STR) haplotypes.

The reference database of highly informative Y-chromosomal short tandem repeat (STR) haplotypes (YHRD), available online at http://ystr.charite.de, represents the largest collection of male-specific genetic profiles currently available for European populations. By September 2000, YHRD contained 4688 9-locus (so-called "minimal") haplotypes, 40% of which have been extended further to include two additional loci. Establishment of YHRD has been facilitated by the joint efforts of 31 forensic and anthropological institutions. All contributing laboratories have agreed to standardize their Y-STR haplotyping protocols and to participate in a quality assurance exercise prior to the inclusion of any data. In view of its collaborative character, and in order to put YHRD to its intended use, viz. the support of forensic caseworkers in their routine decision-making process, the database has been made publicly available via the Internet in February 2000. Online searches for complete or partial Y-STR haplotypes from evidentiary or non-probative material can be performed on a non-commercial basis, and yield observed haplotype counts as well as extrapolated population frequency estimates. In addition, the YHRD website provides information about the quality control test, genotyping protocols, haplotype formats and informativity, population genetic analysis, literature references, and a list of contact addresses of the contributing laboratories.

Databases, Factual↗

PubMed2001

Influence of phloretin and 6-ketocholestanol on the permeation of progesterone through porcine skin.

In this study the effect of phloretin (PH) and 6-ketocholestanol (KC) on the permeation of progesterone through porcine skin has been examined. Both PH and KC were incorporated into unilamellar L-alpha-phosphatidylcholine (PC) liposomes at different concentrations (7.5, 15, 30 and 60 mol%). In diffusion experiments with porcine skin, both substances, to a different degree, enhanced the steady state flux of progesterone. It was increased up to 2.4-fold using 15 mol% KC, and 1.4-fold using 30 mol% PH. The results indicate an interaction of these two compounds with the lipid components of the stratum corneum. In order to visualise the interaction, differential scanning calorimetry (DSC) measurements were performed on porcine skin, which had been impregnated with KC and PH. Both showed a lowering ( approximately 5-6 degrees C) in the lipid phase transition temperature that occurs around 75 degrees C in porcine skin.

Animals↗

PubMed2001

Heat-induced formation of a specific binding site for self-assembled Congo Red in the V domain of immunoglobulin L chain lambda.

Moderate heating (40-50 degrees C) of immunoglobulins makes them accessible for binding with Congo Red and some related highly associated dyes. The binding is specific and involves supramolecular dye ligands presenting ribbon-like micellar bodies. The L chain lambda dimer, which upon heating disclosed the same binding requirement with respect to supramolecular dye ligands, was used in this work to identify the site of their attachment. Two clearly defined dye-protein (L lambda chain) complexes arise upon heating, here called complex I and complex II. The first is formed at low temperatures (up to 40-45 degrees C) and hence by a still native protein, while the formation of the second one is associated with domain melting above 55 degrees C. They contain 4 and 8 dye molecules bound per L chain monomer, respectively. Complex I also forms efficiently at high dye concentration even at ambient temperature. Complex I and its formation was the object of the present studies. Three structural events that could make the protein accessible to penetration by the large dye ligand were considered to occur in L chains upon heating: local polypeptide chain destabilization, VL-VL domain incoherence, and protein melting. Of these three possibilities, local low-energy structural alteration was found to correlate best with the formation of complex I. It was identified as decreased packing stability of the N-terminal polypeptide chain fragment, which as a result made the V domain accessible for dye penetration. The 19-amino acid N-terminal fragment becomes susceptible to proteolytic cleavage after being replaced by the dye at its packing locus. Its splitting from the dye-protein complex was proved by amino acid sequence analysis. The emptied packing locus, which becomes the site that holds the dye, is bordered by strands of amino acids numbered 74-80 and 105-110, as shown by model analysis. The character of the temperature-induced local polypeptide chain destabilization and its possible role in intramolecular antibody signaling is discussed.

Amino Acid Sequence↗

PubMed2001

Zebrafish admp is required to restrict the size of the organizer and to promote posterior and ventral development.

Bone morphogenetic proteins (Bmps) and their roles during early dorsoventral patterning of the vertebrate embryo are well understood. The role and regulation of a more distant member of this family, the anti-dorsalizing morphogenetic protein (Admp), however, are less clear. Here, we report the isolation and characterization of zebrafish admp. Unlike other bmps, admp is exclusively expressed on the dorsal side. Expression starts at blastula stages in the region of the organizer, giving rise to anterior neuroectoderm and axial mesoderm. During the course of gastrulation, both the neuroectodermal and the mesodermal admp transcripts vanish in an anterior-posterior wave. The maintenance of admp expression is positively influenced by Nodal signaling and by Bozozok (Boz), an organizer-promoting homeodomain protein acting as a repressor of early bmp2b expression. Despite the positive effect of boz on admp expression, Boz and Admp have rather opposite effects on zebrafish patterning, as revealed in gain- and loss-of-function experiments. Upon overexpression, admp has Bmp-like activities causing a smaller organizer and enhanced ventral specification, very similar to the phenotype caused by the loss of boz function in mutant embryos. Antisense-based admp knockdown, on the other side, leads to an enlarged organizer and impaired ventral and posterior development, as observed in embryos after boz overexpression. This finding indicates that admp is required for the development of embryonic structures normally suppressed by organizer activities. The seeming discrepancy between the regulative and functional relationship of boz and admp is discussed, and models are proposed according to which Admp might be part of a negative feedback loop to pattern and confine the organizer region.

Animals↗

PubMed2001

Precuneus-prefrontal activity during awareness of visual verbal stimuli.

Awareness is a personal experience, which is only accessible to the rest of world through interpretation. We set out to identify a neural correlate of visual awareness, using brief subliminal and supraliminal verbal stimuli while measuring cerebral blood flow distribution with H(2)(15)O PET. Awareness of visual verbal stimuli differentially activated medial parietal association cortex (precuneus), which is a polymodal sensory cortex, and dorsolateral prefrontal cortex, which is thought to be primarily executive. Our results suggest participation of these higher order perceptual and executive cortical structures in visual verbal awareness.

Adult↗

PubMed2001

Stereochemistry of cleavage of internucleotide bonds by Serratia marcescens endonuclease.

Endonuclease from Serratia marcescens hydrolyzes internucleotide phosphorothioate linkages of R(P) configuration with inversion of configuration at P-atom. This observation supports a reported architecture of the active site, with 3'-bridging and pro-S(P) non-bridging oxygen atoms of the scissile phosphate group involved in direct contact with hydrated magnesium cation, while His-89 activates a water molecule which attacks the phosphorus atom according to a one-step in-line mechanism. The presence of a phosphorothioate bond of S(P) configuration downstream to that one being cleaved reduces the rate of hydrolysis. This suggests participation of the pro-S(P) oxygen atom of that phosphate bond in the mechanism of action of the enzyme, which was not detected in published crystallographic analyses.

Catalysis↗

PubMed2001

The effect of target-selection strategy on phonological learning.

In this study, 48 children with moderate or severe delays in phonological ability received treatment for four phonemes, selected in accordance with either traditional or nontraditional target-selection criteria. Children who received treatment for phonemes that are early developing and associated with greater productive phonological knowledge showed greater progress toward acquisition of the target sounds than did children who received treatment for late-developing phonemes that were associated with little or no productive phonological knowledge. Between-group differences in generalization learning were not observed. Child enjoyment of therapy did not differ between groups, but parental satisfaction with treatment progress was greater for children in the traditional group than for children in the nontraditional group.

Articulation Disorders↗

PubMed2001

Accelerated healing of pyoderma gangrenosum treated with bioengineered skin and concomitant immunosuppression.

Pyoderma gangrenosum is a rare, destructive, neutrophilic dermatosis, the origin of which remains largely obscure. The ulcerative variant of this inflammatory disorder causes painful, necrotic, rapidly enlarging ulcers. Because of pathergy, many clinicians avoid managing these nonhealing ulcers with aggressive surgical debridement and autologous grafts. This article proposes that the application of an allogeneic cultured human skin equivalent (Graftskin) not only circumvents this problem, but also hastens re-epithelialization of the ulcer bed. An added benefit of the possible improvement of the cosmetic appearance of the final scar by preventing severe wound contracture is also postulated. We report a newly diagnosed case of ulcerative pyoderma gangrenosum; the use of bioengineered skin as an adjunct to concurrent immunosuppressive therapy with cyclosporine hastened the healing and diminished pain in a rapidly enlarging leg ulcer. Within 2 weeks, the ulcer was 30% to 40% healed, achieving 100% re-epithelialization within 6 weeks.

Adult↗

PubMed2001

Cholecystokinin stimulates aldosterone secretion from dispersed rat zona glomerulosa cells, acting through cholecystokinin receptors 1 and 2 coupled with the adenylate cyclase-dependent cascade.

Cholecystokinin is a regulatory peptide, that acts through two subtypes of receptors, 1 and 2. RT-PCR demonstrated the expression of both cholecystokinin receptors 1 and 2 genes in the zona glomerulosa, but not the zona fasciculata-reticularis, of rat adrenals. Autoradiography demonstrated the presence of abundant [(125)I]cholecystokinin-binding sites in the zona glomerulosa, but not the zona fasciculata-reticularis, which were displaced by both cholecystokinin receptor 1- and 2-selective antagonists (cholecystokinin 1-A and 2-A). Cholecystokinin increased basal aldosterone secretion from dispersed zona glomerulosa cells without affecting corticosterone secretion from zona fasciculata-reticularis cells. The aldosterone response to cholecystokinin was blunted by cholecystokinin 1-A and 2-A, which when added together abolished it. ACTH-stimulated aldosterone production was not affected by cholecystokinin; in contrast, cholecystokinin potentiated aldosterone response to both angiotensin II and K(+). Cholecystokinin enhanced cAMP, but not IP(3), release by dispersed zona glomerulosa cells. The aldosterone response to cholecystokinin was abolished by the adenylate cyclase inhibitor SQ-22536 and the PKA inhibitor H-89, but not by either the PLC inhibitor U-73122 or the PKC inhibitor calphostin C. In conclusion, our study provides evidence that cholecystokinin, acting through cholecystokinin receptors 1 and 2 coupled with the adenylate cyclase/PKA cascade, exerts a sizeable secretagogue action on rat zona glomerulosa cells.

Adenylyl Cyclases↗

PubMed2001

Prolonged orexin administration stimulates steroid-hormone secretion, acting directly on the rat adrenal gland.

Orexins A and B are two hypothalamic peptides, that play a role in the central control of food intake. Orexins act via two subtypes of receptors: OX1R which is selective for orexin A, and OX2R which binds both orexins. Reverse transcription-polymerase chain reaction demonstrated the expression of both OX1R and OX2R gene in the adrenal cortex of adult female rats. The prolonged systemic administration of orexins A and B (20 ng/kg x day, for 7 days) affected neither adrenal weight and the morphology of adrenocortical zones (as evaluated by morphometric techniques) nor ACTH plasma concentration in rats. In contrast, the treatment with both orexins increased plasma concentration of both aldosterone and corticosterone. Taken together, these findings indicate that orexins exert a marked direct chronic secretagogue action on adrenocortical cells, acting through both OX1R and OX2R.

Adrenal Cortex↗

PubMed2001

Spiral computed tomographic imaging related to computerized ultrasonographic images of carotid plaque morphology and histology.

OBJECTIVE: Echolucency of carotid atherosclerotic plaques, as evaluated by computerized B-mode ultrasonographic images, has been associated with an increased incidence of brain infarcts on cerebral computed tomographic scans. We tested the hypotheses that characterization of carotid plaques on spiral computed tomographic images correlates with that on computerized B-mode ultrasonographic images and that spiral computed tomographic imaging predicts the histomorphometric plaque content. METHODS: The study included 38 patients with neurologic symptoms and at least 50% stenosis of the ipsilateral carotid artery. High-resolution B-mode ultrasonographic images and spiral computed tomographic images of carotid plaques were computer processed to yield a quantitative measure, the gray scale level of the plaque. RESULTS: The mean Hounsfield value for spiral computed tomographic images correlated with the gray scale median for B-mode ultrasonographic images (univariate linear regression analysis: r = 0.45; P = .01) and the histologic content of calcification in the plaque (r = 0.34; P = .04) but not with lipid, hemorrhage, or fibrous tissue in the plaque. CONCLUSIONS: Spiral computed tomographic imaging seems to correlate with B-mode ultrasonographic imaging for showing plaque characteristics. Spiral computed tomographic attenuation was also correlated with the amount of calcification noted on histologic examination but not with lipid and hemorrhage, the components thought to characterize vulnerable, rupture-prone plaques.

Carotid Arteries↗

PubMed2001

Evidence that supramolecular Congo red is the sole ligation form of this dye for L chain lambda derived amyloid proteins.

The mechanism of Congo red binding to amyloid protein was studied in order to establish which of two structural dye versions present in water solutions--unimolecular and supramolecular--represent its actual ligation form. Immunoglobulin L chain lambda of amyloidogenic nature, expressed by Congo red binding and easy gel formation, was used as the model amyloid protein. Congo red was coassembled with rhodamine B, designed to be a marker of the Congo red micellar organisation in complexation with protein. The particular suitability of rhodamine B for this role results from significant difference in its binding affinity to Congo red and to protein. It associates readily with Congo red, becoming incorporated into its micellar organisation, but as homogenous dye it shows an almost complete inability to bind to protein. In view of these properties, Congo red was used as a vehicle to draw rhodamine B into complexation with protein, at the same time supplying evidence of its supramolecular ligation form. The results show that both soluble amyloid precursor L chain and the derived gel material attach rhodamine B coassembled with Congo red but not the homogenous rhodamine B. Despite its dynamic, supramolecular character, Congo red participates in complexation with amyloid proteins as an integral ligand unit.

Amyloid beta-Protein Precursor↗

PubMed2001

[The influence of paternal lymphocytes immunization on percentage of peripheral blood CD16+/CD56+ cells in women with primary recurrent spontaneous abortion].

OBJECTIVES: Paternal lymphocytes immunization has been proposed for several years as an efficient treatment for unexplained Recurrent Spontaneous Abortion (RSA), however precise mechanism that underline the benefits of this immunotherapy is still unclear. DESIGN: The aim was to study the influence of paternal lymphocytes immunization on percentage of peripheral blood NK cells (CD16+/CD56+) in women with primary RSA of unknown etiology. MATERIALS AND METHODS: 48 patients with history of 3-5 (mean 3.3 +/- 0.7) consecutive primary RSA of unknown etiology were selected for the study. Immunotherapy with paternal lymphocytes, isolated from 100 ml of peripheral blood, was performed twice prior conception with a 4-week interval. The percentage of NK cells (CD16+/CD56+) was estimated using standard flow-cytometric immunofluorescent techniques for whole blood with one-step monoclonal anti-CD16/CD56 antibodies. Statistical analysis was performed with Wilcoxon test and the p value less than 0.05 was accepted as statistically significant. RESULTS: It was found that paternal lymphocytes immunization significantly decreases the percentage of NK cells in peripheral blood in women with RSA (23.9 +/- 8.5 vs. 16.2 +/- 7.0; p = 0.009). CONCLUSIONS: The data of the present studies suggest that paternal lymphocytes immunization modulate immunity in women with primary unexplained RSA significantly decreasing the percentage of NK cells (CD16+/CD56+) in peripheral blood.

Abortion, Habitual↗

PubMed2001

[Maternal serum cytokines in labor, pregnancy and chorioamnionitis].

UNLABELLED: The purpose of our study was to compare maternal serum levels of interleukin-6, interleukin-8, tumor necrosis factor-alpha and interferon-gamma in gravidities, during spontaneous term and preterm labor and their relation to histologic chorioamnionitis. METHODS: We investigated 61 women: 10 in preterm labor, 36 in term labor and 15 healthy pregnant nonlabouring controls. Venous bloods for cytokines determinations were obtained during the first stage of labor and during routine screening tests. Titers of cytokines were measured by means of ELISA technique. All births after preterm deliveries were examined to establish histologic chorioamnionitis. RESULTS: Serum levels of IL-6 and IL-8 were significantly elevated both in term (mean: IL-6: 17.5 +/- 58 pg/ml; IL-8: 148 +/- 215 pg/ml) and preterm labor (IL-6: 23 +/- 44 pg/ml; IL-8: 332 +/- 389 pg/ml) when compared to nonlabouring gravidities (IL-6: 5 +/- 7 pg/ml; IL-8: 14 +/- 11 pg/ml). IL-6 and IL-8 titers were statistically similar in term and preterm labors and in patients with and without histologic chorioamnionitis. TNF-alpha and IFN-gamma were not statistically analyzed because only a few patients had detectable serum levels of these cytokines. CONCLUSION: Serum levels of IL-6 and IL-8 in both: term and preterm labor are elevated in comparison to nonlabouring gravidities. The elevated levels of these cytokines are not connected with coexisting chorioamnionitis.

Adult↗

PubMed2001

[Parameters of peripheral whole blood neutrophil activity in women with pregnancy induced hypertension].

OBJECTIVES: Pregnancy induced hypertension is believed to be a state of neutrophil overactivity, however all previous studies were done on isolated cells. DESIGN: To study neutrophil activity in whole blood of PIH women. MATERIALS AND METHODS: Neutrophil activity was estimated without isolation, in peripheral whole blood of 23 PIH women and 26 normal pregnant controls. The chemiluminescence test was performed without any stimulation and upon stimulation of neutrophils with fMLP, OZ and PMA, before and after pre-activation with TNF-alpha. The results were corrected according to the haemoglobin concentration and (%) of neutrophils. The percentage of whole blood neutrophils indicating expression of selectins CD18, CD11b, integrin CD62L and mean fluorescence intensity (MFI) of these molecules were studied on flow-cytometry. RESULTS: The study revealed that neutrophil chemiluminescence was not significantly higher in PIH women and after correction coefficient used it was even lower in PIH patients. TNF-alpha preactivation had no influence on chemiluminescence results. Expression of CD11b expressed as MFI value was significantly increased while that of CD62L, expressed as (%) of positive cells and MFI value--decreased in PIH patients. CONCLUSIONS: Changes of neutrophil CD11b and CD62 expression indicate increased activity of these cells in PIH women, however low production of reactive oxygen species estimated by corrected chemiluminescence test especially after TNF-alpha pre-activation, indicates that this form of their reactivity is rather "exhausted" during PIH.

Adult↗

PubMed2001

[Decidual lymphocyte subsets in pregnant women].

OBJECTIVES: Materno-foetal immunological reactions in decidua are probably one of the most important elements in pathogenesis of preeclampsia. DESIGN: To compare lymphocyte subsets isolated from decidua of preeclamptic pregnant women with lymphocyte subsets isolated from healthy pregnant women. MATERIALS AND METHODS: Preeclampsia (PE) was defined according to USA National Health Institute criteria. The study group consisted of 21 women with PE and 11 women with physiological pregnancy. All pregnancies were finished with elective cesarean sections. Exclusion criteria were: uterine contractions, infection, chorinamnionitis, diabetes mellitus and therapy with steroids less than 7 days before blood sampling. Decidual tissue was obtained by curettage of the uterine cavity. The fragments of decidua were separated from clotted blood and placed in sterile tubes with 5 ml of isotonic solution (PBS). Then the decidual tissue was mechanically fragmented, homogenized and rinsed in PBS. Routine immunofluorescent marking techniques with monoclonal antibodies were performed. Analysis was done with FACSCalibur flow-cytometer with 488 nm argon laser using CellQuest programme. The following lymphocyte subsets were estimated: CD3, CD19, CD4, CD8, CD4/CD29, CD8/CD28, CD4/CD45RA, CD4/CD45RO, CD56/CD16, CD69. The results were described as percentage of lymphocytes positive for above surface molecules. Statistical analysis was performed using t-Student and U-Mann-Whitney tests. The work was sponsored by KBN 4 P05E 118 15 grant. RESULTS: Decidua of pregnant PE women contains significantly increased percentage of CD3-/ CD56 + 16+, CD8+/CD28+ cells and decreased percentage of CD3+, CD19+, CD4+/CD29+ and CD4+/CD45RA+ compared to decidua of healthy pregnant controls. CONCLUSIONS: These changes suggest that deficiency of suppressor activity as well as aberrant immunoregulation exists in decidual tissue of PE women.

Adult↗

PubMed2001

[The place of laparoscopy in gynecological practice--useful technique for diagnostic and treatment of infertility and endometriosis].

OBJECTIVE: The objective was to evaluate indications for laparoscopy performed in Department of Gynecological Surgery of Polish Mother's Memorial Research Institute. MATERIALS AND METHODS: We have analyzed hospital charts of 342 patients who had been treated with laparoscopy in 1991-1999. RESULTS: During last years a progressive frequency in performing laparoscopic procedures has been noted (4.7% of all surgical treatment in 1991-93, 6.4% in 1994-96, 16.3% in 1997-99, and 25.2% in 1999). An increased percentage of operative laparoscopic procedures has also been observed (11.9% in 1991-93 vs 59.8% in 1994-96 vs 86.9% in 1997-99). The major indication for performing laparoscopy was: infertility (145--42.4%), endometriosis (90--26.4%) and benign ovarian tumors. Most of laparoscopic operations were performed due to benign pathological changes found in adnexa (218--68.6%). Laparoscopy has been recently introduced in surgical treatment of uterine myoma (enucleation, laparoscopically assisted vaginal hysterectomy-LAVH) and diagnosis of ovarian carcinoma. Complications were found in 19 (5.5%) cases: 11 cases (3.2%) intraoperative and 8 (2.3%) cases postoperative. Bleeding from abdominal wall vessels was the most often intraoperative complications, whereas an infection was the most common postoperative one. Because of complications laparoscopy turned into laparotomy in four cases. CONCLUSION: Laparoscopy is a safe and useful technique for treatment some gynecological pathology (especially infertility and endometriosis) with a small number of complications.

Endometriosis↗

PubMed2001

[Serum cytokines in patients with ovarian cancer and benign ovarian cysts].

UNLABELLED: The aim of our study was to evaluate serum interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) as tumor markers--study based on the data about tumor cytokines production and tumor-host interactions. METHODS: We investigated 48 women: 17 with ovarian cancer untreated before, 16 with benign ovarian cysts and 15 healthy controls. Venous blood for cytokines determinations were obtained before operations and during routine screening tests. Titers of cytokines were measured by means of ELISA technique. RESULTS: In the control group the upper limit of normal IL-6 titers (95th percentile) was 5.5 pg/ml; the mean IL-8 concentration was 9.6 +/- 15.1 pg/ml and the upper limit of normal was 37 pg/ml; serum TNF-alpha and IFN-gamma were not detectable. In patients with benign ovarian cysts the levels of all investigated cytokines didn't differ significantly from healthy controls. Women with ovarian cancer had significantly higher serum IL-8 levels (mean: 290.5 +/- 351 pg/ml) than healthy controls or women with benign ovarian cysts; 88% of them had IL-8 titers above the normal. The IL-6 titers in ovarian cancer were also higher but didn't reach statistical significance, 53% of them had IL-8 titers above the normal. TNF-alpha and IFN-gamma levels in ovarian cancer were similar to patients with benign ovarian cysts. CONCLUSION: Serum IL-8 levels in patients with ovarian cancer were significantly higher when compared to healthy controls and benign ovarian cysts and in almost 90% of ovarian cancers the titers of IL-8 were increased. Additionally, 53% of women with ovarian cancer had elevated serum IL-6 levels.

Biomarkers, Tumor↗