bluuebunny/crossref_metadata_2025_split huggingface dataset:
Funneling to the stitch: an informative ultrasonographic finding after cervical cerclage
Authors: O'Brien J. M. , Hill A. L. , Barton J. R. 
Published: March 2003

AbstractObjectiveThe purpose of this study was to evaluate the utility of ultrasound surveillance after cerclage placement and to propose a rationale for cervical sonography in this setting.Subjects and methodsThis was a retrospective analysis of 53 women undergoing cervical cerclage by a maternal‐fetal medicine specialist, regardless of indication, and delivering between January 1999 and April 2001. Transvaginal ultrasonographic assessment of cervical length and the degree of cervical funneling after cerclage were compared to preoperative values and to outcomes including gestational age at delivery. Funneling to the cerclage was defined as membranes prolapsing down the endocervical canal until they reached the plane of the cerclage.ResultsCervical cerclage resulted in a significant increase in cervical length from 2.1 ± 1.2 cm to 2.9 ± 0.8 cm after the procedure, P < 0.001; however, this measure was not correlated with gestational age at delivery. Funneling to the level of the cerclage was associated with an earlier gestational age at delivery 31.3 ± 5.6 weeks vs. 36.8 ± 2.8 weeks for those cases without this finding, P < 0.001. A statistically significant association between funneling to the cerclage and preterm delivery was identified irrespective of the indication (prophylactic or emergency) for the procedure. When descent of the membranes to the level of the cerclage was noted, it occurred by 28 weeks' gestation in all patients studied. The incidence of premature rupture of the membranes was also significantly greater postcerclage in women with descent of the membranes to the cerclage (52%) compared to those without this finding (9%) P = 0.002.ConclusionsFunneling to the cerclage is significantly associated with earlier preterm delivery in patients who have undergone cervical cerclage. Serial sonography up to 28 weeks' gestation is useful in identifying patients at higher risk for premature rupture of the membranes and preterm delivery. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
Venous Doppler velocimetry in the surveillance of severely compromised fetuses
Authors: Hofstaetter C. , Gudmundsson S. , Hansmann M. 
Published: March 2003

AbstractObjectiveTo investigate whether venous Doppler velocimetric signs of cardiac decompensation might predict fetal demise in severely compromised fetuses.Material and methodsThis was a prospective study involving 154 growth‐restricted fetuses, 37 of which were found to have reversed flow in the umbilical artery (BFC III). Doppler velocimetry of the right hepatic vein and ductus venosus were investigated serially and the presence of umbilical venous pulsations also registered. Only the final examination prior to birth or fetal demise was accepted for analysis and related to obstetric outcome defined as gestational age at birth, birth weight and perinatal mortality. In cases of BFC III the venous velocimetry of 15 nonsurviving fetuses was compared to that of the 22 survivors.ResultsThere was a significant correlation between venous blood velocity and placental vascular resistance. In the right hepatic vein there was a significant decrease in peak systolic and end‐systolic velocities and an increase of maximum velocity during atrial contraction and pulsatility (P < 0.05). A decrease of all velocities and increase of pulsatility were noted in the ductus venosus (P < 0.05). A reversed flow in the ductus venosus was found in 9/37 fetuses and double umbilical venous pulsations in 16/37 fetuses. However, the hepatic vein seemed to be a better predictor of impending mortality than the ductus venosus. Changes in diastolic venous blood velocity and a double pulsation in the umbilical vein were closely related to perinatal mortality, although these parameters did not provide a useful threshold to optimize the timing of delivery.ConclusionDiastolic venous velocimetry changes significantly in severely compromised fetuses. These changes might be of great clinical value in deciding on the timing of delivery to minimize damage to the fetus and newborn. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
Hypophosphatasia associated with increased nuchal translucency: a report of two affected pregnancies
Authors: Souka A. P. , Raymond F. L. , Mornet E. , Geerts L. , Nicolaides K. H. 
Published: March 2003

AbstractPerinatal hypophosphatasia is a lethal autosomal recessive skeletal abnormality with a birth prevalence of about 1 per 100 000. It is characterized by deficiency of the tissue‐nonspecific isoenzyme of alkaline phosphatase causing abnormal bone mineralization. In the two affected fetuses from the same family ultrasound examination at 14 and 12 weeks, respectively, demonstrated increased nuchal translucency thickness, hypomineralization of the skull and spine, narrowing of the chest and shortening of the limbs. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
Operative fetoscopy via telesurgery
Authors: Quintero R. A. , Muñoz H. , Pommer R. , Diaz C. , Bornick P. W. , Allen M. H. 
Published: March 2003

AbstractWe describe a case in which telesurgical consultation from Tampa, Florida, USA was used to accomplish operative fetoscopy in Santiago, Chile for the treatment of a twin pregnancy involving an acardiac twin. The procedure was successful and a healthy infant was delivered at 37.5 weeks. Operative fetoscopy, a surgical approach to correct birth defects in utero via combined ultrasound and endoscopy, is only available in a handful of centers worldwide. Telesurgery makes use of telecommunication to allow a surgeon at a primary operating site to consult with another experienced surgeon for complex surgical cases. This case illustrates the potential for ultrasound and telesurgery to expand the horizons of operative fetoscopy. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
Prenatal diagnosis of interruption of the aortic arch and its association with deletion of chromosome 22q11
Authors: Volpe P. , Marasini M. , Caruso G. , Gentile M. 
Published: March 2003

AbstractObjectivesDifferentiation of interruption of the aortic arch (IAA) type A from type B by prenatal echocardiography is possible but difficult. We report nine consecutive cases of the prenatal detection of IAA and evaluate the feasibility of making a correct prenatal diagnosis with fetal echocardiography. The incidence of 22q11 microdeletion in our series, detected using fluorescent in situ hybridization (FISH) analysis, was determined.MethodsEchocardiography and FISH for the DiGeorge critical region (22q11) were performed in all cases. The findings were confirmed by autopsy (three cases) or at postnatal surgery (six cases).ResultsOn fetal echocardiography we identified six type B cases and three type A. FISH detected microdeletions in 22q11 in five of nine fetuses (four type B cases and an unusual association with type A in one case).ConclusionsOur report confirms the feasibility of making a correct prenatal diagnosis of IAA and its different types, based on echocardiographic examination. Furthermore our data are consistent with previous reports indicating that type A and type B are distinct entities. In more than 50% of fetuses with IAA type B, 22q11 microdeletion and DiGeorge or velo–cardio–facial syndromes may be expected. IAA type A is not commonly associated with 22q11 hemizygosity. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
A superficial ulnar artery anastomosing with a larger anterior interosseous artery to supply the wrist and hand
Authors: SAÑUDO J. R. , MIRAPEIX R. M. , GARCIA R. , RODRIGUEZ‐NIDENFÜNR M. 
Published: March 2003

The term superficial ulnar artery (SUA) is applied to an artery which arises from the axillary, brachial or superficial brachial arteries and courses over the origins of the superficial forearm muscles to join at the midlevel of the forearm with the ulnar artery, sometimes replacing it (Wankoff, 1962; Lippert & Pabst, 1985; Nakatani et al. 1996, 1997). Its incidence ranges from 0.7% (Adachi, 1928) to 3.3% (Müller, 1903). The SUA has been reported with different terminologies; arteria antebrachialis superficialis ulnaris (Gruber, 1867; Müller, 1903; Adachi, 1928), high origin of the ulnar artery (Rodriguez‐Baeza et al. 1995; Aharinejad et al. 1997) and SUA with a high origin (Fuss, 1988).The present observation adds several aspects to the anatomical variations of the superficial ulnar arteries already described, most notably its anastomosis with the anterior interosseous artery. This anastomosis has previously been reported twice (Quain, 1844; Gruber, 1867) but without explanation as to the course taken by the anastomotic branch. The SUA was found in the right arm of a 66‐y‐old male during routine dissections in the Unit of Anatomy and Embryology at the Autonomous University of Barcelona.
NADPH‐diaphorase distribution in the rabbit superior colliculus and co‐localization with calcium‐binding proteins
Authors: González‐Soriano Juncal , Contreras‐Rodríguez Julio , Martínez‐Sainz Pilar , Martín‐Palacios Susana , Marín‐García Pilar , Rodríguez‐Veiga Elisia 
Published: March 2003

AbstractNitric oxide (NO) and calcium‐binding proteins (CaBP) are important neuromodulators implicated in brain plasticity and brain disease. In addition, the mammalian superior colliculus (SC) has one of the highest concentrations of NO within the brain. The present study was designed to determine the distribution of nitric oxide‐synthesizing neurons in the SC of the rabbit by enzyme histochemistry for reduced nicotinamide adenine dinucleotide phosphate‐diaphorase (NADPH‐d), and its degree of co‐localization with CaBP, parvalbumin (PV) and calbindin (CB). NADPH‐d‐labelled fibres formed dense patches of terminal buttons within the intermediate grey layer and streams of fibres within the deepest layers of SC. Cells expressing NOS constitute a subpopulation of neurons in which practically all cell types are represented. Combined PV/NADPH‐d experiments showed a complete lack of co‐localization within individual neurons and fibres. On the contrary, double‐labelled neurons appeared in CB/NADPH‐d‐stained sections, only in the superficial layers, and mostly in the SGS and SO. These cells, which were intermingled with other neurons containing either NADPH‐d or CB, appear to be a subtype of narrow‐field and wide‐field vertical cells, and display an anterior–posterior gradient of density. Owing to the involvement of the superficial layers of the SC in the organization and integration of the visual information, it is suggested that these neurons may play a concrete role within the visual circuits. Our data indicate a clear selectivity in the expression of NADPH‐d, PV and CB in the SC, and that NO and CB probably serve as co‐modulators and/or co‐transmitters in the connectivity of the superficial layers of this midbrain structure.
Stem cells: potency, plasticity and public perception*
Authors: Gardner R. L. 
Published: March 2003

AbstractProduction of chimaeras with embryonal carcinoma and embryonic stem cells enabled a very thorough investigation of the potency of these cells in the mouse. Human embryonal carcinoma and embryonic stem cell differ from their murine counterparts in a number of respects and, for obvious reasons, their potency is more difficult to assess. Recently, findings attesting to a surprising degree of plasticity of cells from adults have begun to emerge, which, aside from offering a possible further route to stem cell therapy, raise intriguing questions about the importance of lineage in the process of cellular diversification. Biomedical research is widely perceived to be advancing too fast to allow proper consideration of the implications of its clinical applications. Whilst this was clearly not true in the case of human in vitro fertilization, it has some validity regarding stem cell therapy, even though many of the issues are common to both. Casual use of the term ‘embryo’ proved unhelpful in the past debate on whether research on early stages of human development should be permitted. Likewise, introduction of the term ‘therapeutic cloning’ has complicated the present one regarding extension of such research to stem cell therapy.
Extracellular matrix, junctional integrity and matrix metalloproteinase interactions in endothelial permeability regulation*
Authors: Alexander J. S. , Elrod John W. 
Published: March 2003

AbstractVascular endothelial permeability is maintained by the regulated apposition of adherens and tight junctional proteins whose organization is controlled by several pharmacological and physiological mediators. Endothelial permeability changes are associated with: (1) the spatial redistribution of surface cadherins and occludin, (2) stabilization of focal adhesive bonds and (3) the progressive activation of matrix metalloproteinases (MMPs). In response to peroxide, histamine and EDTA, endothelial cells sequester VE‐cadherin and alter its cytoskeletal binding. Simultaneously, these mediators enhance focal adhesion to the substratum. Oxidants, cytokines and pharmacological mediators also trigger the activation of matrix metalloproteinases (MMPs) in a cytoskeleton and tyrosine phosphorylation dependent manner to degrade occludin, a well‐characterized tight junction element. These related in vitro phenomena appear to co‐operate during inflammation, to increase endothelial permeability, structurally stabilize cells while also remodelling cell junctions and substratum.
Parathyroid hormone‐related protein (PTHrP) production sites in elasmobranchs
Authors: Trivett M. K. , Walker T. I. , Macmillan D. L. , Clement J. G. , Martin T. J. , Danks J. A. 
Published: March 2003

AbstractThis study describes the distribution of parathyroid hormone‐related protein (PTHrP) antigen and its mRNA in seven species of cartilaginous fish from six elasmobranch families. Antigen was detected using antibodies to synthetic human PTHrP and the mRNA with a riboprobe to human PTHrP gene sequence. The distribution pattern of PTHrP in the cartilaginous fish studied, reflected that observed in mammals but PTHrP further occurs in some sites unique to cartilaginous fish. Of particular note was the demonstration of PTHrP in the shark skeleton, which although considered not to contain bone, may form by a process similar to that forming the early stages of mammalian endochondral bone. The distribution of PTHrP in the elasmobranch skeleton resembled the distribution of PTHrP in the developing mammalian skeleton. Differences in the staining pattern between antisera to N‐terminal PTHrP and mid‐molecule PTHrP in the brain and pituitary suggested that the PTHrP molecule might be post‐translationally processed in these tissues. The successful use of antibodies and a probe to human PTHrP in tissues from the early vertebrates examined in this study suggests that the PTHrP molecule is conserved from elasmobranchs to humans.
Seed mass, habitat conditions and taxonomic relatedness: a re‐analysis of Salisbury (1974)
Authors: KELLY C. K. 
Published: March 2003

SUMMARYRe‐analysis of data from Salisbury (1974) shows no significant relationship between seed size and habitat conditions, a relationship for which this paper is frequently cited as support. The discrepancy between the results reported here and those found in the original paper is due to Salisbury's ‘evidence’ being a table of congeneric pairs collected specifically because they possessed the target relationship. This paper emphasizes particularly the need for an unbiased sampling of species pairs in comparisons attempting to define ecological relationships. The analysis presented here represents the fourth such instance in which previously assumed robust examples of the relationship between seed size and habitat type are shown not to be so when the appropriate methods are used to account for relatedness among species.
A stay‐green mutation of Lolium perenne affects NO3− uptake and translocation of N during prolonged N starvation
Authors: BARKEN ANNE KJERSTI , MACDUFF JAMES , HUMPHREYS MERVYN , RAISTRICK NEIL 
Published: March 2003

SUMMARYApparent Km and Vmax for net NOS″ uptake and short‐term translocation patterns of recently absorbed N were compared in a stay‐green mutant and wild‐type selection line of Lolium perenne L. by means of a series of depletion studies using 18NO3, performed over 12 d under conditions of progressively increasing N deprivation. In view of the greater retention of N in senescent leaves of the stay‐green phenotype, it was predicted that NOS″ uptake would be up‐regulated relative to the normal line, and that a proportionally higher fraction of recently absorbed N would be allocated to young leaves. It was shown that the stay‐green trait had significant phenotypic consequences for plant N relations, with higher ‘sink strength‘ of shoots for recently absorbed N, and higher Vmaxfor NO3 uptake compared with those of normal plants. The stay‐green mutation had no effect on the Km of the nitrate uptake system. Although the N‐use efficiency might he expected to be lower in stay‐green than in normal plants, there were no differences in rates of dry matter production.
The effect of NaCl on growth, dry matter allocation and ion uptake in salt marsh and inland populations of Armeria maritima
Authors: KÖHL KARIN I. 
Published: March 2003

SUMMARYSalt resistance was compared in populations of Armeria maritima (Mill.) Willd. from salt marshes and from inland sites to investigate which salt‐resistance‐related traits are present in all populations and which are derived traits of the salt‐marsh ecotype. Plants were raised from seeds from six different populations and grown on a mixture of sand and ion‐exchange resin at different salinity levels. Inland populations grew better at 40 mM NaCl than with salt‐free treatment and survived several months at 200 mM NaCl, and were thus as salt‐resistant as many species from brackish habitats. Salt‐marsh populations were as salt‐resistant as euhalophytes. Growth enhancement by NaCl was related to an increase in shoot:root d. wt ratio, which was shown not to be the result of damage to the roots. Carbon allocation to roots seemed to be reduced as a consequence of a better nutrient supply at elevated NaCl concentrations. In plants from all populations, tissue tolerance of sodium and chloride (500–1000 mmol kg−1 d. wt) was higher than that in glycophytes. Na substituted for K and to some extent Ca and Mg without growth reduction. Betaines were accumulated as cytoplasmic compatible solutes by all populations, whereas proline accumulation was not involved in adjustment to long‐term salt stress. The halophytic capacity to load the xylem with Na was found in all populations of A. maritima. However, the allocation of Na to the shoot started at higher salinities in inland populations than in salt‐marsh populations. This was presumably due to the Na storage capacity of roots of inland populations being higher than that of coastal populations. Nevertheless, the inland populations of A. maritima were significantly salt‐tolerant as a consequence of their capacity to accumulate betaines and allocate Na to the shoot; this might have facilitated the colonization of salt marshes by the species.
A fructan: fructan fructosyltransferase activity from Lolium rigidum
Authors: ST. JOHN J. A. , BONNETT G. D. , SIMPSON R. J. , TANNER G. J. 
Published: March 2003

SUMMARYFructan: fructan fructosyltransferase (FFT) activity was purified about 300‐fold from leaves of Lolium rigidum Gaudin by a combination of affinity chromatography, gel filtration, anion exchange and isoelectric focusing. The FFT activity was free of sucrose: sucrose fructosyltransferase and invertase activities. It had an apparent pI of 4.7 as determined by isoelectric focusing, and a molecular mass of about 50000 (gel filtration). The FFT activity utilized the trisaccharides 1‐kestose and 6G‐kestose as sole substrates, but was not able to use 6‐kestose as sole substrate. The FFT activity was not saturated when assayed at concentrations of 1‐kestose, 6G‐kestose or (1,1)‐kestotetraose of up to 400 mM The rate of reaction of the FFT activity was most rapid when assayed with 1 ‐kestose and was less rapid when assayed with 6G kestose, (1,1)‐kestotetraose or (1,1,1)‐kestopentaose. The FFT activity when assayed at a relatively high concentration of enzyme activity (approximately equivalent to about half the activity in crude extracts per gram fresh mass) did not synthesize fructan of degree of polymerization > 6, even during extended assays of up to 10 h. When assayed with a combination of 1‐kestose and uniformly labelled [14C]sucrose as substrates, was the transfer of a fructosyl residure from 1‐kestose to sucrose resulting in the re‐synthesis of 1‐kestose. Tetrasaccharide and 6G‐kestose were also synthesized. When assayed with 6G‐kestose and [14C]sucrose as substrates, the major reaction of the FFT activity was the synthesis of tetrasaccharide. However, some synthesis of 1‐kestose and re‐synthesis of 6G‐kestose also occurred. When 6G‐kestose was the sole substrate for the FFT activity, synthesis of tetrasaccharide was 2.7 to 3.4‐fold slower than when 1‐kestose was used as the sole substrate. Owing to differences in the fructan: sucrose fructosyltransferase activity of the FFT with each of the trisaccharides, net synthesis of tetrasaccharide by the FFT was altered significantly in the presence of sucrose. The magnitude of this effect depended on the concentration of the trisaccharides. In the presence of sucrose, 6G‐kestose could be a substrate of equivalent importance to 1‐kestose for synthesis of tetrasaccharide.
Polyphosphates in the red macroalga Chondrus crispus (Rhodophyceae)
Authors: CHOPIN T. , LEHMAL H. , HALCROW K. 
Published: March 2003

SUMMARYPlants of Chondrus crispus Stackhouse, collected from mid‐littoral tidepools, were treated as follows. Some plants were kept for a few weeks under controlled starvation conditions in order to decrease their initial content of total tissue phosphorus, then incubated for up to 48 h in phosphorus (15 μm) and nitrogen (25 μM)enriched sea water. Other plants were directly incubated in enriched sea water. Chemical analyses showed that the total phosphorus content of fresh and starved plants remained stable, reflecting the nutritional status of the plants. The predominant acid‐soluble phosphate fraction was larger in fresh than in starved plants. The content of acid–soluble polyphosphates, similar in both types of plants at the beginning of the experiment, doubled in starved plants, and increased by a factor of 2′7 in fresh plants, over 48 h. The content of acid‐insoluble polyphosphates was lower than that of acid‐soluble polyphosphates.Transmission electron microscopy and energy dispersive X–ray microanalysis confirmed the presence, mostly in medullary cells, of acid‐insoluble polyphosphates in the form of cytoplasmic granules and precipitates along the plasmalemma, particularly near pit plugs. This is the first report of such phosphorus storage structures in a red macroalgal species.