The Frequency and Clinical Significance of Twin Gestations According to Zygosity and Chorionicity

2010 ◽  
Vol 13 (6) ◽  
pp. 609-619 ◽  
Author(s):  
Kyung A. Lee ◽  
Kyung Joon Oh ◽  
Seung Mi Lee ◽  
Ahm Kim ◽  
Jong Kwan Jun
Keyword(s):  
Clinical Significance ◽  
Dna Analysis ◽  
Perinatal Death ◽  
Molecular Genetic ◽  
Accurate Determination ◽  
Clinical Importance ◽  
University Hospital ◽  
Dna Analyses ◽  
Mz Twins

Background:Although the clinical importance of chorionicity in twin pregnancies has been studied widely, the significance of perinatal determination of zygosity using molecular genetic analyses remains controversial. The purpose of this study was to determine the frequency and clinical significance of twin gestations according to zygosity and chorionicity in a Korean population.Methods:We enrolled 569 women who delivered twin newborns (> 24 weeks) at Seoul National University Hospital between 1999 and 2008. Chorionicity was established by histologic examination of placentae. Zygosity was determined with sex of neonates, chorionicity, and DNA analysis of umbilical cord blood.Results:The frequency of dizygotic (DZ) twins was 71.0% (404/569 pairs) based on the opposite sex (238/404 [58.9%]) and DNA analyses (166/404 [41.1%]); that of monozygotic (MZ) twins was 29.0% (165/569), including monochorionic (MC) (72.1% [119/165]) and dichorionic (DC) twins (27.9% [46/165]), which was confirmed by DNA analyses. Among spontaneously conceived twins, the frequency of MZ twins was more than twice that of DZ twins. The risk of low birth weight was 1.8-fold higher among MZDC twins and 1.9-fold higher among MZMC twins than among DZDC twins (p< .05). Bronchopulmonary dysplasia occurred more frequently among MZMC twins than among DZDC twins (adjusted OR 8.42, 95% CI 1.82–39.08,p< .01). However, the frequencies of other neonatal morbidities were not significantly higher in the MZMC group than in the MZDC and DZDC groups. The perinatal mortality rate was 15 per 1000 total births in the DZDC twins, 20 per 1000 total births in the MZDC and 56 per 1000 total births in the MZMC (p< .01).Conclusions:Although monozygosity was shown to be a risk factor for perinatal death and accurate determination of zygosity plays a great role in the future consideration of organ transplantation and twin studies, the value of zygosity determination along with chorionicity in relation to overall neonatal morbidity was not definite.

Clinical Significance of Antithrombin

1979 ◽  
Author(s):  
G. Sas
Keyword(s):  
Clinical Significance ◽  
Oral Anticoagulants ◽  
Clinical Importance ◽  
Rapid Rise ◽  
Functional Abnormality ◽  
Antithrombin Deficiency ◽  
Clinical Investigations ◽  
The Family ◽  
Contraceptive Treatment

The clinical importance of antithrombin was directly proved by the description of the first hereditary antithrombin deficiency /HAD/ in 1965. Several other families have been studied since that time. Two main types of /HAD/ can be discerned. In one, both immunologic and fuctional methods reveal low level of antithrombin in the affected members. Some biochemical observations suggest the heterogenity even of this type of HAD. Oral anticoagulants seem effective in the treatment and prophylaxis of these patients. Thus, determination of antithrombin level should be performed in all young thrombotic patients especially. with prevalence of thromboembolism in the family. The second type of HAD, the congenital functional abnormality of antithrombin is very rare. Oestrogenic hormones can decrease the synthesis of antithrombin. This observation might be connected with •the thromboembolic complications of oral contraceptives. More data ar needed to evaluate the usefulness of monitoring the antithrombin level in the course of contraceptive treatment to avoid these complications. Decreased antithrombin levels and detection of antithrombin-complexes can provide useful information in the diagnosis of hypercoagulable states. Due to the methodologic development experienced in the last few years, one can expect a rapid rise of clinical investigations bringing about a better knowledge of clinical significance.

scholarly journals DNA ISOLATION FROM HUMAN URINE STAIN AS AN ALTERNATIVE MATERIAL FOR PERSONAL IDENTIFICATION EXAMINATION

2017 ◽  
Vol 52 (4) ◽  
pp. 277 ◽  
Author(s):  
Ahmad Yudianto ◽  
Yeti Eka Sispitasari
Keyword(s):  
Dna Analysis ◽  
Accurate Determination ◽  
Gc Content ◽  
Vaginal Swab ◽  
Personal Identification ◽  
The Body ◽  
Buccal Swab ◽  
Judicial Process ◽  
Alternative Material

Accurate determination of personal identity is crucial for an investigation since any inaccuracy may lead to fatal consequences in the judicial process. Identification through DNA analysis involves somatic chromosomes and mtDNA. Each part of the human body can be taken as a specimen since every nucleated cell in the body of an individual has identical DNA sequence. To date, samples for identification through DNA analysis are obtained from blood stains, semen stains, bones, vaginal swab, buccal swab etc. In certain cases, urine stains on the clothing have frequently been overlooked. So far, personal identification through DNA analysis by the use of urine stains has not been commonly carried out. The present study detected bands in the loci CSF1PO, THO1, TPOX and 106bp-112bp amelogenin in all samples visualized from the results of Polymerase Chain Reaction (PCR) with Polyacrylamid Agarose Gel Electrophoreses-silver staining for exposure durations of 1, 7 and 14 days. However, for exposure duration of 20 days (the maximum in the study), bands were only detected in the loci THO1 and TPOX in all samples (100%), whereas the loci CSF1PO and 50% amelogenin exhibited obvious bands. This indicated that DNA analysis of urine stains through detection of the locus STR CSF1PO, THO1, TPOX exhibited different detection responses for different exposure durations assigned to the samples of urine stain. Successful detection of these loci was supported by the differences in amplicon product and GC content at each locus. Of the loci studied, the ratio of GC content of the primers, sorted from the lowest, were as follows: locus CSF1PO of 42.6 1%, TPOX of 56.25%, and THO1 of 63.83%. In conclusion, the loci THO1 and TPOX had the same probability of success in the STR examination compared with the locus CSF1PO.

scholarly journals Serologically Weak D-phenotype: Review and Interpretation of Blood Group RhD

2020 ◽  
Vol 5 (5) ◽  
pp. 45-52
Author(s):  
R. P. Pavliuk ◽  
Keyword(s):  
Pregnant Women ◽  
Accurate Determination ◽  
Clinical Importance ◽  
Scientific Justification ◽  
Serological Studies ◽  
International Laboratory ◽  
Complete Set ◽  
Polymerase Chain ◽  
D Antigen

The Rhesus system is the second most important erythrocyte system for transfusion after ABO. Accurate determination of the Rhesus status of the donor, recipient, pregnant allows to prevent the development of post-transfusion hemolytic complications of the fetus or newborn associated with incompatibility of the blood of the mother and the fetus by D antigen. Generally, determination of the Rhesus affiliation of a person is performed by serological methods using anti-Rhesus reagents with full or incomplete antibodies. However, the results of serological studies are not always clear. Mutations and other effects of the RH gene locus disrupt the production of the normal D antigen and lead to the emergence of numerous varieties of antigen D. The variant of antigen D was described in 1946 and was designated as Du. The study showed that the differences between Du antigen and normal D were quantitative rather than qualitative. The Du antigen was later designated as Dweak - a weak D-antigen or a weak D-phenotype. In the early 1950s, anti-D antibodies were detected in recipients with a weak D-antigen after transfusion with Rh-positive blood and in pregnant women with the Du phenotype during pregnancy and at the birth of a D+ baby. It was suggested that the D antigen was not homogeneous and consisted of numerous partial variants: D1, D2, D3, etc. A complete set of partial variants corresponds to a complete D-antigen. The absence of any of one or more partial factors leads to the appearance of attenuated forms of the D antigen, denoted as Dpartial. People lacking certain partial antigens can produce anti-D antibodies against them. Differentiation of weak D phenotypes has great clinical importance, because transfusion of Rh-erythrocytes to recipients with Dweak and who are actually Rh-positive, has no scientific justification and leads to unjustified consumption of deficient blood and unnecessary immunoprophylaxis of anti-Rh immunoglobulin to pregnant women. International laboratory practice has no unified policy regarding the diagnosis of weak variants of D antigen and the interpretation of the results. Polymerase chain reaction allows to accurately define the Rh status of an individual and to avoid unreasonable transfusions of Rh-negative blood and unnecessary immunoprophylaxis

scholarly journals Morphological Characterisation And Molecular Sex Determination Of Human Remains From The 15th–17th Centuries In Latvia

2015 ◽  
Vol 69 (1-2) ◽  
pp. 8-13 ◽  
Author(s):  
Asta Ščėsnaitė-Jerdiakova ◽  
Liāna Pliss ◽  
Guntis Gerhards ◽  
Elīna Pētersone Gordina ◽  
Agnija Gustiņa ◽  
...  
Keyword(s):  
Sex Determination ◽  
Dna Analysis ◽  
Molecular Genetic ◽  
Skeletal Remains ◽  
Human Skeletal Remains ◽  
Full Agreement ◽  
Archaeological Material ◽  
Molecular Approaches ◽  
Molecular Sex Determination

Abstract Sex determination is one of the most important and initial steps in human profile identification from archaeological material. The aim of the current study was to evaluate the application of molecular approaches alongside morphological methods for sex determination in archaeological human skeletal remains. Human skeletal remains were excavated from three cemeteries: St Gertrude Old Church, Dom Square and St Peter’s Church, of 15th–17th century burials in Rīga, Latvia. Morphological and molecular genetic methods, including amplification of genes AMELX/Y and SRY were used to analyse seven skeletal remains. The conducted analyses of morphological features identified sex in all seven cases (two females and five males). By molecular analyses of mediaeval DNA it was possible to determine sex in five of seven (71%) samples. In all positive cases full agreement between morphological estimation and molecular genetic methods was observed. To conclude, DNA analysis can be considered for sex identification in cases with no signs of sexual dimorphism (juvenile skeletons) or partially preserved skeletons.

scholarly journals Sex determination of skeletal remains of 4000 year old children and juveniles from Hoštice 1 za Hanou (Czech Republic) by ancient DNA analysis

2008 ◽  
Vol 71 (1) ◽  
pp. 63-70 ◽  
Author(s):  
Michaela Vaňharová ◽  
Eva Drozdová
Keyword(s):  
Czech Republic ◽  
Sex Determination ◽  
Ancient Dna ◽  
Dna Analysis ◽  
Molecular Genetic ◽  
Skeletal Remains ◽  
Burial Site ◽  
Ancient Dna Analysis ◽  
Bell Beaker

Sex determination of skeletal remains of 4000 year old children and juveniles from Hoštice 1 za Hanou (Czech Republic) by ancient DNA analysisThe aim of this study was to determine the sex by means of modern molecular genetic methods of children and immature individuals from the 4000 years old Eneolithic burial site "Hoštice 1 za Hanou" of the Bell-Beaker people, in central Moravia (Czech Republic). While the anthropological approach was in this case limited either by the state of preservation of the skeletal remains or simply by absence of definite morphological traits in the children, analysis of aDNA (SRY, amelogenin) yielded results consistent with archeological grave findings and body imposition. The burial rites of the investigated culture facilitated the analysis because the gender specific imposition of adults has previously been described (man left-side, head northwards, woman right-side, head southwards) However, this approach is often limited in case of children burials. This study showed high concordance between archeological sex-determination and genetic sex, but also revealed several exceptions in children burial rite of Bell Beaker culture.

scholarly journals Amperometric Immunosensing Scaffolds for Rapid, Simple, Non-Invasive and Accurate Determination of Protein Biomarkers of Well-Accepted and Emerging Clinical Importance

Proceedings ◽  
2017 ◽  
Vol 1 (8) ◽  
pp. 727
Author(s):  
María Pedrero ◽  
Cristina Muñoz-San Martín ◽  
Rebeca M. Torrente-Rodríguez ◽  
Víctor Ruiz-Valdepeñas Montiel ◽  
Eva Vargas ◽  
...  
Keyword(s):  
Accurate Determination ◽  
Clinical Importance ◽  
Protein Biomarkers ◽  
Non Invasive

A quantitative approach to inner shell losses

1978 ◽  
Vol 36 (1) ◽  
pp. 526-527 ◽  
Author(s):  
R.D. Leapman ◽  
P. Rez ◽  
D.F. Mayers
Keyword(s):  
Energy Transfer ◽  
Cross Section ◽  
Cross Sections ◽  
Accurate Determination ◽  
Background Intensity ◽  
Core Excitation ◽  
Quantitative Basis ◽  
Cross Section Differential ◽  
Bound Electrons

Microanalysis by EELS has been developing rapidly and though the general form of the spectrum is now understood there is a need to put the technique on a more quantitative basis (1,2). Certain aspects important for microanalysis include: (i) accurate determination of the partial cross sections, σx(α,ΔE) for core excitation when scattering lies inside collection angle a and energy range ΔE above the edge, (ii) behavior of the background intensity due to excitation of less strongly bound electrons, necessary for extrapolation beneath the signal of interest, (iii) departures from the simple hydrogenic K-edge seen in L and M losses, effecting σx and complicating microanalysis. Such problems might be approached empirically but here we describe how computation can elucidate the spectrum shape.The inelastic cross section differential with respect to energy transfer E and momentum transfer q for electrons of energy E0 and velocity v can be written as

Fast calibration of CBED patterns for quantitative analysis

1993 ◽  
Vol 51 ◽  
pp. 674-675
Author(s):  
M.A. Gribelyuk ◽  
M. Rühle
Keyword(s):  
Reciprocal Lattice ◽  
Accurate Determination ◽  
Incident Beam ◽  
Crystal Thickness ◽  
Structure Model ◽  
Beam Direction ◽  
Transmitted Beam ◽  
Reciprocal Vector ◽  
On Line

A new method is suggested for the accurate determination of the incident beam direction K, crystal thickness t and the coordinates of the basic reciprocal lattice vectors V1 and V2 (Fig. 1) of the ZOLZ plans in pixels of the digitized 2-D CBED pattern. For a given structure model and some estimated values Vest and Kest of some point O in the CBED pattern a set of line scans AkBk is chosen so that all the scans are located within CBED disks.The points on line scans AkBk are conjugate to those on A0B0 since they are shifted by the reciprocal vector gk with respect to each other. As many conjugate scans are considered as CBED disks fall into the energy filtered region of the experimental pattern. Electron intensities of the transmitted beam I0 and diffracted beams Igk for all points on conjugate scans are found as a function of crystal thickness t on the basis of the full dynamical calculation.

Computer-Assisted High-Re Solution TEM

1990 ◽  
Vol 48 (1) ◽  
pp. 162-163
Author(s):  
F.A. Ponce ◽  
H. Hikashi
Keyword(s):  
Signal To Noise Ratio ◽  
Accurate Determination ◽  
Computer Software ◽  
Video Camera ◽  
Image Contrast ◽  
Objective Lens ◽  
Computer Assisted ◽  
Optical Parameters ◽  
Astigmatism Correction

The determination of the atomic positions from HRTEM micrographs is only possible if the optical parameters are known to a certain accuracy, and reliable through-focus series are available to match the experimental images with calculated images of possible atomic models. The main limitation in interpreting images at the atomic level is the knowledge of the optical parameters such as beam alignment, astigmatism correction and defocus value. Under ordinary conditions, the uncertainty in these values is sufficiently large to prevent the accurate determination of the atomic positions. Therefore, in order to achieve the resolution power of the microscope (under 0.2nm) it is necessary to take extraordinary measures. The use of on line computers has been proposed [e.g.: 2-5] and used with certain amount of success.We have built a system that can perform operations in the range of one frame stored and analyzed per second. A schematic diagram of the system is shown in figure 1. A JEOL 4000EX microscope equipped with an external computer interface is directly linked to a SUN-3 computer. All electrical parameters in the microscope can be changed via this interface by the use of a set of commands. The image is received from a video camera. A commercial image processor improves the signal-to-noise ratio by recursively averaging with a time constant, usually set at 0.25 sec. The computer software is based on a multi-window system and is entirely mouse-driven. All operations can be performed by clicking the mouse on the appropiate windows and buttons. This capability leads to extreme friendliness, ease of operation, and high operator speeds. Image analysis can be done in various ways. Here, we have measured the image contrast and used it to optimize certain parameters. The system is designed to have instant access to: (a) x- and y- alignment coils, (b) x- and y- astigmatism correction coils, and (c) objective lens current. The algorithm is shown in figure 2. Figure 3 shows an example taken from a thin CdTe crystal. The image contrast is displayed for changing objective lens current (defocus value). The display is calibrated in angstroms. Images are stored on the disk and are accessible by clicking the data points in the graph. Some of the frame-store images are displayed in Fig. 4.

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