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1.
Article in English | WPRIM (Western Pacific) | ID: wpr-962515

ABSTRACT

Background@#Multiple gestations, including twin gestations are commonly associated with adverse maternal, perinatal and neonatal outcomes compared with singleton pregnancies. Its incidence has shown a significant increase over the last decades. A retrospective cohort study was made at the Department of Obstetrics and Gynecology by review of medical records of twin pregnancies and their neonates. @*Objective@#The purpose of this study is to describe and compare the outcomes of twin gestation against singleton pregnancies, in terms of the following: the presentation of the twin gestation, chorionicity, the mode and timing of delivery and fetomaternal complications. This study aimed to determine whether an association exists between the twin gestation and adverse perinatal outcomes.@*Methodology@#The study included singletons and twin gestations admitted at a tertiary government hospital admitting section within a ten-year period, 2006-2015. Confirmation of diagnosis of multiple pregnancies was obtained by ultrasound. This retrospective cohort study conducted at a tertiary government hospital included 228 singletons and 110 twin gestations in a ten-year period.@*Results@#Results showed women with twin pregnancies had a higher incidence of preterm labor and delivery. Compared to singleton pregnancies, complications of prematurity are not uncommon in twin gestations. This should encourage prenatal and antenatal care in women who have twin gestations.@*Conclusion@#The incidence of preterm labor and delivery for twin gestation, relative to singletons, was high in the study. Twin gestations are 3-4 times more likely to present with preterm labor relative to singletons.


Subject(s)
Morbidity
2.
Front Physiol ; 8: 437, 2017.
Article in English | MEDLINE | ID: mdl-28694782

ABSTRACT

Objectives: This descriptive study was performed to evaluate the capability of a non-invasive transabdominal electrocardiographic system to extract clear fetal electrocardiographic (FECG) measurements from intrauterine growth restricted (IUGR) fetuses and to assess whether abdominal FECG parameters can be developed as markers for evaluating the fetal cardiac status in IUGR. Methods: Transabdominal FECG was attempted in 20 controls and 15 IUGR singleton pregnancies at 20+0-33+6 weeks gestation. Standard ECG parameters were compared between the study groups and evaluated for their correlation. Accuracy for the prediction of IUGR by cut off values of the different FECG parameters was also determined. Results: Clear P-QRST complexes were recognized in all cases. In the IUGR fetuses, the QT and QTc intervals were significantly prolonged (p = 0.017 and p = 0.002, respectively). There was no correlation between ECG parameters and Doppler or other indices to predict IUGR. The generation of cut off values for detecting IUGR showed increasing sensitivities but decreasing specificities with the prolongation of ECG parameters. Conclusion: The study of fetal electrocardiophysiology is now feasible through a non-invasive transabdominal route. This study confirms the potential of FECG as a clinical screening tool to aid diagnosis and management of fetuses after key limitations are addressed. In the case of IUGR, both QT and QTc intervals were significantly prolonged and thus validate earlier study findings where both these parameters were found to be markers of diastolic dysfunction. This research is a useful prelude to a test of accuracy and Receiver Operating Characteristics (ROC) study.

3.
Zoology (Jena) ; 119(4): 375-83, 2016 08.
Article in English | MEDLINE | ID: mdl-27289265

ABSTRACT

Recent research provides accumulating evidence that the evolutionary dynamics of host-parasite adaptations strongly depend on environmental variation. In this context, the three-spined stickleback (Gasterosteus aculeatus) has become an important research model since it is distributed all over the northern hemisphere and lives in very different habitat types, ranging from marine to freshwater, were it is exposed to a huge diversity of parasites. While a majority of studies start from explorations of sticklebacks in the wild, only relatively few investigations have continued under laboratory conditions. Accordingly, it has often been described that sticklebacks differ in parasite burden between habitats, but the underlying co-evolutionary trajectories are often not well understood. With the present review, we give an overview of the most striking examples of stickleback-parasite-environment interactions discovered in the wild and discuss two model parasites which have received some attention in laboratory studies: the eye fluke Diplostomum pseudospathacaeum, for which host fish show habitat-specific levels of resistance, and the tapeworm Schistocephalus solidus, which manipulates immunity and behavior of its stickleback host to its advantage. Finally, we will concentrate on an important environmental variable, namely temperature, which has prominent effects on the activity of the immune system of ectothermic hosts and on parasite growth rates.


Subject(s)
Cestode Infections/veterinary , Fish Diseases/parasitology , Smegmamorpha , Trematode Infections/veterinary , Animals , Cestoda/classification , Cestode Infections/parasitology , Ecosystem , Temperature , Trematoda/classification , Trematode Infections/parasitology
4.
Protein Expr Purif ; 89(2): 210-8, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23563167

ABSTRACT

The HNH family of endonucleases is characterized by a ßßα metal-finger structural motif. Colicin E7 is a representative member of this family containing the strictly conserved HNH motif at its C-terminus. Structural and biochemical studies suggested that the HNH motif could contain all the residues necessary for metal ion binding and nuclease activity. In this work a 43 amino acid peptide extending from V534 to K576 of colicin E7 and encompassing the HNH motif was cloned and expressed in Escherichia coli as a ubiquitin fusion protein. The N-terminal fusion tag was cleaved off by a specific protease, and the HNH peptide was purified free of ubiquitin. Circular dichroism, fluorescence and mass spectrometry showed that the zinc-ion binding affinity of the purified HNH peptide was much weaker than that of the intact nuclease domain suggesting that the N-terminal part of the nuclease domain is essential for stabilizing the structure of the HNH motif. The coordination sphere of the metal ion was found to be not fully equipped by the ligand - leaving a free coordination site for the substrate. Neither DNA binding nor DNAse activity of the purified HNH peptide was detected. Comparison of the glutathion-S-transferase-fused N-terminal deletion mutants of the colicin E7 nuclease domain suggested that the presence of the DNA-binding site is still not sufficient for the catalytic activity.


Subject(s)
Cloning, Molecular , Colicins/genetics , Colicins/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Zinc/metabolism , Amino Acid Motifs , Amino Acid Sequence , Colicins/chemistry , Colicins/isolation & purification , DNA/metabolism , Deoxyribonucleases/chemistry , Deoxyribonucleases/metabolism , Escherichia coli/chemistry , Molecular Sequence Data , Peptides/chemistry , Peptides/genetics , Peptides/isolation & purification , Peptides/metabolism , Protein Structure, Tertiary , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/metabolism , Ubiquitin/chemistry , Ubiquitin/genetics , Ubiquitin/isolation & purification , Ubiquitin/metabolism
5.
J Biol Inorg Chem ; 18(3): 309-21, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23334162

ABSTRACT

Colicin E7 (ColE7) is a metallonuclease toxin of Escherichia coli belonging to the HNH superfamily of nucleases. It contains highly conserved amino acids in its HHX(14)NX(8)HX(3)H ßßα-type metal ion binding C-terminal active centre. However, the proximity of the arginine at the N-terminus of the nuclease domain of ColE7 (NColE7, 446-576) is necessary for the hydrolytic activity. This poses a possibility of allosteric activation control in this protein. To obtain more information on this phenomenon, two protein mutants were expressed, i.e. four and 25 N-terminal amino acids were removed from NColE7. The effect of the N-terminal truncation on the Zn(2+) ion and DNA binding as well as on the activity was investigated in this study by mass spectrometry, synchrotron-radiation circular dichroism and fluorescence spectroscopy and agarose gel mobility shift assays. The dynamics of protein backbone movement was simulated by molecular dynamics. Semiempirical quantum chemical calculations were performed to obtain better insight into the structure of the active centre. The longer protein interacted with both Zn(2+) ion and DNA more strongly than its shorter counterpart. The results were explained by the structural stabilization effect of the N-terminal amino acids on the catalytic centre. In agreement with this, the absence of the N-terminal sequences resulted in significantly increased movement of the backbone atoms compared with that in the native NColE7: in ΔN25-NColE7 the amino acid strings between residues 485-487, 511-515 and 570-571, and in ΔN4-NColE7 those between residues 467-468, 530-535 and 570-571.


Subject(s)
Colicins/chemistry , Colicins/metabolism , Endonucleases/chemistry , Endonucleases/metabolism , Escherichia coli/metabolism , Amino Acid Sequence , Catalytic Domain , Colicins/genetics , DNA, Bacterial/metabolism , Endonucleases/genetics , Escherichia coli/chemistry , Escherichia coli/genetics , Molecular Dynamics Simulation , Molecular Sequence Data , Protein Binding , Protein Conformation , Protein Structure, Tertiary , Sequence Deletion , Zinc/metabolism
6.
Opt Lett ; 34(4): 533-5, 2009 Feb 15.
Article in English | MEDLINE | ID: mdl-19373365

ABSTRACT

We show a system capable of projecting a video scene onto a white-light holographic screen to obtain a kind of image that results in a plane in front of the screen. This holographic screen is mainly a diffractive lens and is constructed by holography. The image plane can be located at any azimuth angle and seen with continuous parallax and without the use of goggles or any special visualization equipment. The image is not volumetric, but when the plane is oblique to the observer its appearance looks very close to a real volumetric image.

7.
J Opt Soc Am A Opt Image Sci Vis ; 25(5): 1091-7, 2008 May.
Article in English | MEDLINE | ID: mdl-18451915

ABSTRACT

A pseudoscopic (inverted depth) image made with spiral diffracting elements intermediated by a pinhole is explained by its symmetry properties. The whole process is made under common white light illumination and allows the projection of images. The analysis of this projection demonstrates that the images of two objects pointing away longitudinally have the main features of standard pseudoscopic image points. An orthoscopic (normal depth) image has also been obtained with the breaking of the symmetry conditions.

8.
J Inorg Biochem ; 102(7): 1438-48, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18289685

ABSTRACT

The copper(II), nickel(II) and zinc(II) binding ability of the multi-histidine peptide N-acetyl-His-Pro-His-His-NH(2) has been studied by combined pH-potentiometry and visible, CD and EPR spectroscopies. The internal proline residue, preventing the metal ion induced successive amide deprotonations, resulted in the shift of this process toward higher pH values as compared to other peptides. The metal ions in the parent [ML](2+) complexes are exclusively bound by the three imidazole side chains. In [CuH(-1)L](+), formed between pH 6-8, the side chains of the two adjacent histidines and the peptide nitrogen between them are involved in metal ion binding. The next deprotonation results in the proton loss of the coordinated water molecule (CuH(-1)L(OH)). The latter two species exert polyfunctional catalytic activity, since they possess superoxide dismutase-, catecholase- (the oxidation of 3,5-di-tert-butylcatechol) and phosphatase-like (transesterification of the activated phosphoester 2-hydroxypropyl-4-nitrophenyl phosphate) properties. On further increase of the pH rearrangement of the coordination sphere takes place leading to the [CuH(-3)L](-) species, the deprotonated amide nitrogen displaces a coordinated imidazole nitrogen from the equatorial position of the metal ion. The shapes of the visible and CD spectra reflect a distorted arrangement of the donor atoms around the metal ion. In presence of zinc(II) the species [ZnL](2+) forms only above pH 6, which is shortly followed by precipitation. On the other hand, the [NiL](2+) complex is stable over a wide pH range, its deprotonation takes place only above pH 8. At pH 10 an octahedral NiH(-2)L species is present at first, which transforms slowly to a yellow square planar complex.


Subject(s)
Metals/chemistry , Oligopeptides/chemistry , Cations, Divalent , Copper , Enzymes , Hydrogen-Ion Concentration , Molecular Mimicry , Molecular Structure , Nickel , Potentiometry , Solutions , Spectrum Analysis , Zinc
9.
J Inorg Biochem ; 101(10): 1376-85, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17628687

ABSTRACT

The systematic investigation of the copper(II) complexes of tripeptides Xaa-Xaa-His, Xaa-His-Xaa and His-Xaa-Xaa, where Xaa=Gly or Ala was performed by combined pH-metry, spectrophotometry, CD and in part EPR spectroscopy. The matrix rank analysis of the spectral data revealed the number of the coloured and optically active species as a basis for the solution speciation. A critical evaluation on the speciation and solution structure of the complexes formed is presented on the basis of their d-d band optical activity. The replacement of a Gly residue with the chiral Ala amino acid allowed us to gain decisive information on the solution structure of the complexes by CD spectroscopy. It was shown that the tripeptides with histidine in the third position formed CuH(-2)L species with (NH(2), 2N(-), ImN - where Im stands for imidazole) coordination sphere as a major species, and only the macrochelated CuL complexes as minor species around pH 5.0. In copper(II)-Xaa-His-Xaa tripeptide systems the CuH(-1)L (NH(2), N(-), ImN) is the most stable species at physiological pH, but the vacant fourth site around copper(II)ions is offered for further deprotonation, most probably resulting in mixed hydroxo species at low (<5 x 10(-4)M) metal ion concentrations, while a tetrameric complex is dominant when the copper concentration exceeds 3 x 10(-3)M. The histamine type coordination mode in CuL and CuL(2) complexes of His-Xaa-Xaa ligands predominates at low pH. The structural consequences drawn from the CD spectra for the mono and bis parent complexes were supported by theoretical calculations. CD spectra strongly suggest the participation of the imidazole nitrogen both in the Cu(2)H(-2)L(2) and CuH(-2)L complexes.


Subject(s)
Circular Dichroism/methods , Copper/chemistry , Histidine/chemistry , Peptides/chemistry , Electron Spin Resonance Spectroscopy , Hydrogen-Ion Concentration
10.
J Opt Soc Am A Opt Image Sci Vis ; 23(5): 1021-6, 2006 May.
Article in English | MEDLINE | ID: mdl-16642178

ABSTRACT

Pseudoscopic (inverted depth) images that keep a continuous parallax were shown to be possible by use of a double diffraction process intermediated by a slit. One diffraction grating directing light to the slit acts as a wavelength encoder of views, while a second diffraction grating decodes the projected image. The process results in the enlargement of the image under common white light illumination up to infinite magnification at a critical point. We show that this point corresponds to another simple-symmetry object-observer system. Our treatment allows us to explain the experience by just dealing with main ray directions.

13.
Rev Med Chil ; 123(5): 612-6, 1995 May.
Article in Spanish | MEDLINE | ID: mdl-8525208

ABSTRACT

We report a retrospective review of eight patients (one male), aged 19 to 31 years old, with systemic toxocariasis (visceral larva migrans), seen at the Salvador Hospital of Santiago. Four cases had heart involvement, three had lung involvement and in two, several organs were affected. Seven cases had leukocytosis (range 14, 5 to 160 x 10(9)/l) and all had eosinophilia (35 to 90%). Serum ELISA titers for Toxocara sp were positive in all cases, ranging from 64 to 1000. Six patients were treated with thiabendazole and one with albendazole. Steroids or hydroxiurea were administered to patients with heart failure or hyperleukocytosis. Subjects with lung involvement recovered quickly but those with cardiac compromise had a partial recovery with frequent decompensations of their cardiac failure and one death. Eosinophilia lasted up to 20 years, in spite of specific treatment. We emphasize the importance of infection prevention, accuracy of diagnosis and the severity of cardiac damage in the adult patient.


Subject(s)
Larva Migrans, Visceral/complications , Larva Migrans, Visceral/diagnosis , Adult , Echocardiography, Doppler , Eosinophilia/parasitology , Female , Heart Failure/parasitology , Humans , Male , Retrospective Studies
14.
Bol Chil Parasitol ; 49(3-4): 52-9, 1994.
Article in Spanish | MEDLINE | ID: mdl-7654285

ABSTRACT

With the objective of defining the intrafamiliar distribution pattern of the infection and illness caused by Toxocara sp., 78 infected families (356 people) were studied for 30 months. At the same time 28 families free of infection were studied, as a control group (97 people). The socioeconomic level was analyzed according to a modified Graffar index. Contac with canine and feline pets, and antecedents of geophagia and onichophagia were found to be risk factors which would facilitate the infection. The average of persons infected, diagnosed by ELISA Toxocara test, was 2.8 per family. The importance of familiar distribution of the infection and its primary prevention is strongly stressed.


Subject(s)
Toxocariasis/epidemiology , Adolescent , Adult , Aged , Animals , Case-Control Studies , Child , Chile/epidemiology , Family Health , Female , Humans , Male , Middle Aged , Prevalence , Prospective Studies , Risk Factors , Seroepidemiologic Studies , Socioeconomic Factors , Toxocara canis/immunology , Toxocariasis/blood
17.
Rev. chil. pediatr ; 55(4): 244-8, 1984.
Article in Spanish | LILACS | ID: lil-22036

ABSTRACT

Se estudiaron clinicamente y mediante examenes de laboratorio 42 ninos infectados por Toxocara sp. La edad promedio de los casos fue de 4 anos 2 meses +/- 3 anos 5 meses. Habia geofagia en 97,6%, grados variables de compromiso pulmonar en 64,3% y hepatomegalia en 59,5% de los pacientes.El fondo de ojos tenia alteraciones en 4,8% de los pacientes. En el hemograma la concentracion de hemoglobina promedio fue de 11,0 g/dl, el recuento de leucocitos promedio 19.213 x mm3 y el de eosinofilos 8.918,9 x mm3. 84,86% de los ninos presentaron niveles de isohemaglutininas > o igual 1:64 y 95,2% titulos de ELISA para Toxocara superiores a esta dilucion. El tratamiento con tiabendazol fue bien tolerado en 83,3% y efectivo en 70,8% de los ninos. En 29,2% se observo mejoria parcial clinica y de laboratorio


Subject(s)
Infant , Child, Preschool , Child , Adolescent , Humans , Male , Female , Larva Migrans, Visceral , Enzyme-Linked Immunosorbent Assay
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