Nasal bone in screening for Trisomy 18 and 13 at 11-13 + 6 weeks of gestation - own experiences

OBJECTIVES

The objective of the paper is the suitability assessment of screening for Trisomy 18 and 13 on the basis of NT measurement, FHR, double test and assessment of Nasal Bone.

MATERIAL AND METHODS

The study was performed in 6,661 singleton pregnancies. In each fetus NT, FHR, DV-PIV were examined. Double test from maternal blood was examined. These ultrasound and biochemical factors were in combined screening investigated. Additional ultrasound marker - Nasal Bone was and its impact on Trisomies 18 and 13 screening was examined.

RESULTS

Two groups of patients were compared - with chromosomal normal and chromosomal abnormalities - Trisomy 18 and 13. Detection Rate of Trisomies 18 and 13 at the risk cutoff 1/300 using combined screening was 84.1% and FPR was 7.1%. Detection Rates of examined chromosomal abnormalities using screening with additional marker - NB was 93.2% and False Positive Rate - 5.6%.

CONCLUSIONS

It should be noted that the qualitative analysis of the assessment of NB in the first trimester significantly influences the improvement of screening values focusing on Trisomy 18 and 13 detection. In summary, our research indicates a more effective type of Trisomy 13 and 18 screening using NT, double test, maternal age, CRL and FHR as well as nasal bone presence and absence.

High pressure Raman scattering study on Sm2Mo4O15 system

High-pressure Raman experiments were performed on Sm₂Mo₄O₁₅ system up to 7.9GPa. We show that this system exhibits an irreversible structural amorphization at 5.0GPa. In contrast to any other molybdates and tungstates experiencing pressure-induced amorphization, this structural change in Sm₂Mo₄O₁₅ has strongly first-order character. This amorphous phase can be originated from the hindrance of a crystalline structural phase transition from the P1¯ to P2/m structure. Additionally, the assignment of Raman modes of the ambient-pressure phase of Sm₂Mo₄O₁₅ was proposed based on lattice dynamics calculations.

Screening for trisomy 18 using traditional combined screening vs. ultrasound-based protocol in tertiary center environment

OBJECTIVES

To compare the screening performances of combined screening test risk algorithm for trisomy 18 (T18) using various cutoffs with a multiparameter ultrasound-based method. To compare the general and maternal age (MA)-based screening performances for T18 by means of combined screening and an ultrasound-based method.

METHODS

This was a prospective, multicenter study based on a mixed-risk non-selected population of women referred to referral centers for a first-trimester screening. Each subject was offered a choice between either a traditional combined screening (CSG arm) or an ultrasound-based screening (USG arm). General and MA-based screening performances were measured.

RESULTS

The study population comprised 10 820 pregnancies as follows: 5132 in the CSG arm, including 28 cases of T18, and 5688 in the USG arm, including 29 cases of T18. In the CSG arm, the detection rate (DR) for T18 at a false-positive rate (FPR) of 3% was 86%, whereas the DR was 100% for the USG arm. MA influenced the T18 screening performance in the CSG arm and reduced the DR in MA ranges  <26 years and 31-35 years. This influence was not observed in the USG arm.

CONCLUSIONS

Only, a multiparameter ultrasound-based screening method may be considered an effective alternative to combined screening for T18 screening. The technique exhibits high and stable DRs irrespective of MA.

Functional up-converting SrTiO3:Er(3+)/Yb(3+) nanoparticles: structural features, particle size, colour tuning and in vitro RBC cytotoxicity

SrTiO3 nanoparticles co-doped with a broad concentration range of Er(3+) and Yb(3+) ions were fabricated using the citric route as a function of annealing temperatures of 500-1000 °C. The effect of a broad co-dopant concentration range and sintering temperature on structural and up-conversion properties was investigated in detail by X-ray diffraction techniques and optical spectroscopy. The TEM technique was used to estimate the mean particle size, which was around 30 nm for the inorganic product annealed at 600 °C. Up-conversion emission color tuning was achieved by particle size control. Power dependence of the green and red emissions was found to be a result of temperature determination in the operating range of SrTiO3 nanoparticles and a candidate for the fast and local microscopic heating and heat release induced by IR irradiation. The color changed from white-red-yellow-green upon an increase of sintering temperature, inducing changes in the surface-to-volume ratio and the number of optically active ions in particle surface regions. The cytotoxic activity of nanoparticles on human red blood cells was investigated, showing no harmful effects up to a particle concentration of 0.1 mg ml(-1). The cytotoxic response of a colloidal suspension of nanoparticles to RBC cells was connected with the strong affinity of SrTiO3 particles to the cell membranes, blocking the transport of important biological solutes.

Lattice dynamics and pressure-induced phase transitions in α-BaTeMo2O9

Orthorhombic α-BaTeMo2O9 nonlinear optical single crystals were investigated at ambient pressure by micro-Raman and infrared spectroscopy with a focus on the polarization properties of the vibrational modes. These results were analyzed based on classical lattice dynamics calculations, allowing us to propose the normal-mode symmetries and assignments. In addition to the ambient-pressure studies, high-pressure Raman scattering studies were performed. These studies showed the onset of a reversible first-order phase transition near 3.5 GPa. The pressure dependence of Raman bands provides strong evidence that the phase transition involves significant distortion of the TeOx (x = 3,4) polyhedra, whereas the MoO6 octahedra are less affected. A large increase in the number of observed bands points to lower symmetry of the high-pressure phase.

Temperature-dependent Raman and IR studies of multiferroic MnWO4 doped with Ni2+ ions

Temperature-dependent Raman and IR studies of MnWO(4) crystal doped with Ni(2+) ions were performed in the 4.2-300 K range. These studies were complemented by magnetization and specific heat measurements in the 2-100K range, which revealed that MnWO(4) crystal doped with Ni(2+) ions exhibits two phase transitions at 13.9 and 12.5K. Temperature evolution of Raman wavenumbers and linewidths revealed anomalous behaviour at low temperatures. These anomalies have been attributed to spin-phonon coupling, which appear due to onset of antiferromagnetic spin ordering. The observed anomalies extend above T(N)=13.9 K. This behaviour is consistent with the fact that MnWO(4) is a moderately magnetically frustrated material.

Vibrational properties of RbNd(WO4)2: high pressure Raman study, structural and phonon calculations

RbNd(WO(4))(2) was investigated by high pressure Raman spectroscopy in the 0.1-12.3 GPa pressure interval. The assignment of modes was made based on lattice dynamics calculations and the results of these calculations helped us to also discuss the high pressure behavior of phonon spectra in this material. Our results show that a double oxygen bridge plays a fundamental role in the vibrational properties of this system. A density functional theory (DFT) calculation of hydrostatic pressure effects on RbNd(WO(4))(2) was performed in order to understand the effect of internal bond changes on the vibrational properties of RbNd(WO(4))(2). No pressure induced structural phase transition was observed in the Raman study at room temperature, and the DFT calculation (T = 0 K) is consistent with this result. The anomalous softening of the bridge stretching mode at 770 cm(-1) was attributed to the decrease of W-O1-W bond angle with increasing pressure.

Luminescence and phonon properties of nanocrystalline Bi2WO6:Eu3+ photocatalyst prepared from amorphous precursor

Bi2WO6:Eu3+ samples were prepared by mechanically activated metathesis reaction and subsequent annealing at different temperatures of the as-prepared precursor. X-ray, TEM, Raman, IR, diffuse reflectance and luminescence studies of the prepared samples are presented. It was found that variation of the particle size have significant impact on phonon and emission properties of this material. It was observed that intensity of some Raman and IR bands significantly decreases and the bandwidth of Raman, IR and Eu3+ emission lines significantly increases with decreasing particles size. Moreover, it was observed that intensity ratios I((5)D0-(7)F2)/I((5)D0-(7)F1) and I(5D0_(7)F0)/I((5)D0-(7)F1) increase with decreasing particle size. The observed changes were attributed to phonon confinement effect, decrease in the orthorhombic distortion of the unit cell and concentration increase of surface defects.

Structural and vibrational properties of K(3)Fe(MoO(4))(2)(Mo(2)O(7))-a novel layered molybdate

The new compound K(3)Fe(MoO(4))(2)(Mo(2)O(7)) was synthesized and characterized by a single-crystal x-ray structure determination, and IR and Raman spectroscopic studies. The crystal structure at room temperature and ambient pressure is monoclinic, space group C 2/c, with the unit cell dimensions a = 32.885(7), b = 5.7220(11), c = 15.852(3) Å, β = 91.11°, Z = 8. The FeO(6) octahedra are joined by corners with MoO(4)(2-) tetrahedra and Mo(2)O(7)(2-) units. Some of the K(+) ions form layers in the b × c-plane. The origin of various Raman and IR vibrational modes is discussed. These results indicate that a clear energy gap exists between the stretching and remaining modes. High-pressure Raman scattering studies were also performed. These studies showed the onset of two reversible first-order phase transitions near 1.2 and 7.4 GPa, which are associated with strong distortion of the MoO(4)(2-) and Mo(2)O(7)(2-) units.

Polarised IR and Raman spectra of non-centrosymmetric Na3Li(SeO4)2.6H2O crystal--a new Raman laser material

Polarised IR and Raman spectra of Na3Li(SeO4)2.6H2O single crystal have been recorded. Discussion of the results has been based on the factor group approach for the trigonal R3c (C3v6) space group with Z = 2. The obtained results for the spontaneous Raman scattering have been used in the discussion of the stimulated Raman spectra of the material studied--a new Raman laser crystal.

Size dependent structural, vibrational, and luminescence properties of nanocrystalline LiIn(WO4)2:Cr3+

X-ray, electron transmission spectroscopy, vibrational and luminescence studies of LiIn(WO4)2:Cr+ nanoparticles prepared by Pechini method are reported. On annealing the sample several structural changes were observed resulting in a creation of three new, previously unknown polymorphs. It was shown that this tungstate undergoes two size-induced phase transitions from the structure similar to LiFe(WO4)2 into the structure similar to LiYb(WO4)2 and then into the structure of LiGa(WO4)2 type. These transitions occur for the critical particle size of about 100 and 30 nm, and they could be attributed mainly to some changes in the distribution of the sites occupied by Li+ and In3+ ions. Luminescence studies revealed decrease of the covalent character of chromium environment and electron-phonon coupling strength with decreasing size of the nanoparticles.

Heat capacity, Raman, and Brillouin scattering studies of M2O–MgO–WO3–P2O5 glasses (M=K,Rb)

The authors report the results of temperature-dependent Brillouin scattering from both transverse and longitudinal acoustic waves, heat capacity studies as well as room temperature Raman scattering studies on M2O-MgO-WO3-P2O5 glasses (M=K,Rb). These results were used to obtain information about structure and various properties of the studied glasses such as fragility, elastic moduli, ratio of photoelastic constants, and elastic anharmonicity. They have found that both glasses have similar properties but replacement of K+ ions by Rb+ ions in the glass network leads to decrease of elastic parameters and P44 photoelastic constant due to increase of fragility. Based on Brillouin spectroscopy they show that a linear correlation between longitudinal and shear elastic moduli holds over a large temperature range. This result supports the literature data that the Cauchy-type relation represents a general rule for amorphous solids. An analysis of the Boson peak revealed that the form of the frequency distribution of the excess density of states is in agreement with the Euclidean random matrix theory. The reason of the observed shift of the maximum frequency of the Boson peak when K+ ions are substituted for Rb+ ions is also briefly discussed.

Transvaginal hydrolaparoscopy (THL) in diagnosing infertility

INTRODUCTION

In recent years novel gynecological diagnostic methods have emerged. One of them is transvaginal hydrolaparoscopy (THL). This method allows endoscopic visualization of the organs within the women pelvis accessed through the posterior fornix of the vagina (Veress's needle was used) and with peritoneal distension by saline.

OBJECTIVE

To evaluate a THL as a new technique for diagnosing pelvic pathology.

METHODS AND RESULTS

In years 2002-2004, 56 patients underwent THL due to primary (40 cases) or secondary (16 cases) infertility (age 20-40). None of the patients had any history of previous pelvic surgery and all had normal findings on gynecological examination and vaginal sonography. The quality of the pelvic pictures was satisfactory in all cases. In the infertile group we observed in 42.8% cases of no macroscopic changes, in 57.2% some form of pelvic pathology ; 28.6% of demonstrated endometriosis, and 28.6% had tubal occlusion. There were no complications during or after the operation.

CONCLUSIONS

THL is well-tolerated and accepted by the patients. THL is a safe, simple and inexpensive diagnostic method for pelvic pathology and infertility.

Molecular structure, IR and Raman spectra as well as DFT chemical calculations for alkylaminoacetylureas: vibrational characteristics of dicarbonylimide bridge

The present work reports room temperature IR and Raman study of R-NH-CH2-CO-NH-CO-NH2 alkylaminoacetylureas (R=C3H7, C4H9, C5H11, C6H13, C7H15, C8H17, C9H19, C10H21, C12H25, C14H29, C16H33 and C18H37). The experimental energy levels have been compared to those obtained from DFT chemical quantum calculations performed with the use of B3LYP/6-31G (d,p) basis for the R=C3H7 derivative. Energies of 66 vibrational states have been calculated for this molecule. Its molecular symmetry was taken as C1 and was optimized in the both quantum models applied. The role of the hydrogen bond in the stabilization of the structure has been analyzed.

[Tobacco smoking and body weight of newborns]

Literature data about the effects of tobacco smoke constituents in pregnancy are reviewed. Analysis on the authors material comprises 73 smoking and 70 non-smoking women in pregnancy. In the former group the natal body weight of new born is by 308 g lower and the placental-fetal index by 0.02 higher with no differences in the body weight increase of smoking and non-smoking women in pregnancy.

[Doppler measurements of blood flow in the middle cerebral artery for the diagnosis of fetal anemia]

OBJECTIVES

This paper presents a possibility of non-invasive diagnosis of fetal anemia based on the Doppler assessing of peak systolic velocity (PSV) in the fetal middle cerebral artery. The results of Doppler measurements were compared with fetal peripheral blood count estimated after cordocentesis.

MATERIALS AND METHODS

Doppler measurements of blood flow velocity in the fetal middle cerebral artery were performed in years 2000 and 2001 in 22 pregnancies complicated by maternal blood group alloimmunisation. Gestation age varied from 27 to 36 weeks, the mean gestation age was 32 weeks. Depending on hemoglobin concentration in the fetal blood sample the severity of anemia was divided into three groups: severe anemia (Hb = < 7 g%), middle (Hb = = 8-10 g%) and light (Hb = = 10-12 g%). The fourth group consisted of fetuses without anemia (Hb > 12 g%). The results were statistically analyzed to estimate correlation between the Doppler blood flow indexes (PI, RI, SD and PSV) in the middle cerebral artery and the peripheral blood count (Hb, Ht, erythrocyte count) of fetal blood received by cordocentesis. Using T-Student-test the differences of average maximal blood flow velocities and mean Doppler indexes in the group of fetuses with severe anemia (Hb < 7 g%) and fetuses without anemia (Hb > 12 g%) were compared.

RESULTS

Highest (negative) correlation was found between the peak systolic velocity and the fetal hemoglobin concentration. The correlation index was -0, 85, which means the higher the peak systolic velocity the lower the hemoglobin concentration. The difference between the mean peak systolic velocity in the group of fetuses with severe anemia and the group without anemia was statistically significant (p < 0.001). However, there was no statistical significant difference in the mean peak systolic velocity between the group with middle anemia (Hb = 10-12 g%) and the group without anemia (Hb > 12 g%).

CONCLUSIONS

Doppler ultrasonography with the measurement of peak systolic velocity in the middle cerebral artery is a good method in evaluating of fetal peripheral blood count. Non-invasive peak systolic velocity measurements in the middle cerebral artery allow to assess the fetal hemoglobin concentration and also to reduce the count of diagnostic cordocentesis.

Role of cholecystokinin in the control of gastric emptying and secretory response to a fatty meal in normal subjects and duodenal ulcer patients

BACKGROUND

Exogenous cholecystokinin (CCK) is known to affect gastric motor and secretory activities, but its physiologic role in the control of gastric functions is unknown.

METHODS

In this study involving 10 young healthy subjects and 10 duodenal ulcer (DU) patients, 500 ml of a standard meal without or with addition of 15% soybean oil was given, and the gastric emptying rate and the pH profile and plasma levels of gastrin, CCK, pancreatic polypeptide (PP), and somatostatin were determined in separate tests with placebo or with antagonism of type-A CCK receptors (loxiglumide, 1200 mg orally).

RESULTS

In healthy controls and DU patients the emptying half-time was 44 and 34 min, respectively, and the addition of oil prolonged the emptying by about 50%. Pretreatment with loxiglumide significantly reduced fat-induced retardation of gastric emptying in both healthy controls and DU patients. A standard meal in healthy subjects resulted in an immediate rise in median gastric pH to about 6.0, and this was followed by gradual decrease within about 3 h to premeal values of about 2.0. After the meal, plasma gastrin rose by 57%, CCK by 177%, PP by 100%, and somatostatin by 39%. Addition of fat significantly attenuated and prolonged the pH decrease after the meal while reducing the increment in plasma gastrin and enhancing plasma CCK and PP levels. Loxiglumide significantly reduced the median postprandial pH (from control 4.8 to 2.5) and reversed the changes in the pH profile caused by the addition of fat. The increments in plasma gastrin and CCK were markedly augmented, whereas those of somatostatin and PP were significantly attenuated. DU patients showed lower postprandial pH (3.0) in tests with or without fat and higher increments in plasma gastrin. CCK antagonism failed to affect significantly the pH profile or the increments in plasma gastrin in DU patients.

CONCLUSIONS

These results indicate that endogenous CCK released by a fatty meal delays gastric emptying and inhibits gastric acid and plasma gastrin responses in healthy subjects, but in DU patients the inhibitory effect of CCK is less pronounced, suggesting a defect in the action of this hormone on gastrin release and gastric acid secretion.

Nitric oxide and the interrelation between intestinal motility and pancreatic secretion in fasted and fed dogs

Intestinal motility and pancreatic secretion show synchronous cyclic changes (MMC) that are interrupted by feeding. The aim of this study was to determine the possible implication of nitric oxide (NO) (that was proposed as nonadrenergic noncholinergic neurotransmitter) in the motor and secretory components of MMC in 5 conscious dogs equipped with monopolar electrodes implanted along the small bowel and pancreatic fistulas. In fasted dogs with typical MMCs, L-NNA (an inhibitor of NO synthase) (5 mg/kg-h i.v.) decreased the MMC interval from control value of 80 +/- 7 to 60 +/- 4 min while increasing significantly the slow waves with spikes and suppressing the phase III-related increase in pancreatic secretion. Infusion of L-arginine (L-Arg) (a substrate of NO synthase) (10 mg/kg-h i.v.) increased the MMC interval from control 79 +/- 7 to 96 +/- 8 min and reduced the slow waves spikes by about 25%. Pancreatic secretion showed significant increase to about 20%. CCK maximum. Similar but transient effects were observed when glyceryl trinitrate (GTN) (a donor of NO) (1 mg/kg-h) was administered. After ingestion of meal, the MMC cycles were replaced by irregular spike activity with an average of about 35% slow waves with spikes and pancreatic secretion rose to about 70% of CCK maximum. Infusion of L-Arg (10 mg/kg-h) reduced by about 90% the postprandial spike activity but failed to affect significantly the pancreatic secretion. Also, injection of GTN (1 mg/kg-h) reduced the spike activity but did not influence pancreatic secretion. L-NNA in fed dogs caused an initial increase in spike activity followed by phase III and about 60% inhibition of pancreatic secretion. L-NNA added to L-Arg infusion reversed in part both intestinal motility and pancreatic secretory effects of L-Arg infusion. We conclude that NO system exerts a tonic inhibitory influence on intestinal myoelectric activity by reducing the frequency of MMC pacesetter and by suppressing the postprandial activity but stimulates pancreatic secretion.

Nitric oxide inhibits the myoelectric activity of the small intestine in dogs

Intestinal motility in fasted animals shows cyclic changes (MMC) that are interrupted by feeding. The aim of this study was to determine the possible implication of nitric oxide (NO) (that was proposed as nonadrenergic noncholinergic neurotransmitter) in the motor components of MMC in 5 conscious dogs equipped with monopolar electrodes implanted along the small bowel. In fasted dogs with typical MMCs, L-NNA (an inhibitor of NO synthase) (5 mg/kg-h i.v.) decreased the MMC interval from control 80 +/- 7 to 60 +/- 4 min and increased significantly the spike activity. Infusion of L-arginine (L-Arg) (a substrate of NO synthase) (10 mg/kg-h i.v.) increased the MMC interval from control 79 +/- 7 to 96 +/- 8 min and reduced the slow waves with spikes by about 25%. Similar but transient effects were observed when glycerin trinitrate (GTN) (a donor of NO) (1 mg/kg-h) was administered. After ingestion of meal, the MMC cycles were replaced by irregular spike activity with an average of about 35% slow waves with spikes. Infusion of L-Arg (10 mg/kg-h) reduced by about 90% the postprandial spike activity. Also, infusion of GTN (1 mg/kg-h) strongly reduced the postprandial spike activity. L-NNA in fed dogs caused an initial increase in spike activity followed by phase III-like activity. Similar effects were obtained when L-NNA was infused in dogs with fed-like motility patterns induced by i.v. infusion of caerulein (75 pmol/kg-h). L-NNA added to L-Arg infusion reversed in part the changes of intestinal motility patterns induced by L-Arg. We conclude that NO system exerts a tonic inhibitory influence on intestinal myoelectric activity by reducing the frequency of MMC pacesetter and by suppressing the postprandial spike activity.

Gastric acid inhibitory profile of ebrotidine, a novel H2-receptor antagonist in humans

This study was designed to assess the gastric secretory effects of ebrotidine, a novel H2 receptor antagonist, in humans. Three groups (A, B and C) of male subjects with normal gastric mucosa were used. Group A (6 subjects) was used to determine the dose-dependency of gastric inhibitory effect of ebrotidine on basal and pentagastrin-induced maximal acid output. Group B (8 subjects) was employed to examine the duration of the inhibitory effect of ebrotidine on basal and pentagastrin-induced acid secretion. In group C (6 subjects), the 24h pH-metry was assessed using intraluminal pH-electrode placed in the gastric corpus and connected to a portable recording unit. Single oral dose of ebrotidine (200, 400 or 800 mg) caused a dose-dependent reduction in basal and pentagastrin-induced acid secretion that at a dose of 800 mg amounted to about 89% and 93%, respectively. This inhibition was still observed after 6h and averaged 72% and 50%, respectively. After 12 and 24h upon the drug intake, both basal and pentagastrin-induced acid secretion returned to the control values. Single oral dose of ebrotidine (800 mg) caused a significant reduction in circadian acidity and resulted in a marked and significant reduction of intragastric acidity for about 6h upon the administration. This inhibition was accompanied by a transient increase in basal and postprandial gastrin levels. We conclude that ebrotidine is highly effective inhibitor of basal, pentagastrin-induced and circadian gastric acid secretion in humans.

Role of cholecystokinin in postprandial and vagally stimulated duodenal and gallbladder motility in dogs

This study was designed to determine the role of cholecystokinin (CCK) in postprandial motility pattern of the duodenum and gallbladder (GB) in conscious dogs provided with chronic duodenal electrodes for recording of myoelectric activity and GB fistulas for measurement of intraluminal pressure and volume of GB and to calculate the GB motility index (MI) and GB emptying rate. During naturally occurring activity front (phase III MMC) in the duodenum there was significant increase in the MI of GB accompanied by about 20-30% reduction in the GB volume. These changes in duodenal and GB motility pattern could be duplicated by i.v. motilin. Feeding abolished the appearance of spontaneous activity front in the duodenum and greatly increased motility of GB while reducing its volume. Administration of CCK receptor antagonists in fed dogs failed to affect the motility changes induced by meal in the duodenum but abolished these of the GB. Vagal cholinergic stimulation with insulin, 2DG or urecholine caused similar effects to that induced by food i.e. increased duodenal spike activity, abolished phase III of the MMC, decreased GB volume and increased GB motility. Pretreatment with CCK antagonists did not affect significantly duodenal spike activity or GB motility but significantly increased the GB volume. Atropine 125 micrograms/kg) blocked almost completely spontaneous activity front in the duodenum and accompanying alterations in the motility and volume of GB. We conclude that CCK contributes to the MMC related alterations in the GB motor activity and is essential in cholinergic stimulation induced of the GB emptying but not in vagally induced duodenal and GB motility.