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An updated Atlas of Helophorus chromosomes. COMPARATIVE CYTOGENETICS 2023; 17:295-326. [PMID: 38284104 PMCID: PMC10812385 DOI: 10.3897/compcytogen.17.112831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Accepted: 12/03/2023] [Indexed: 01/30/2024]
Abstract
An account is given of my development of techniques to obtain well-spread Giemsa-stained banded chromosome preparations. Apparent G-banding could be obtained following very slight trypsin treatment of freshly prepared slides, but this banding was very fine (close-grained) and possibly not a reflection of chromosome structure. However, treatment of developing embryos in vitro with 5-fluorouridine produced a similar chromomere banding, which is therefore regarded as genuine. Steady accumulation of Helophorus Fabricius, 1775 karyotypes has resulted in the production of an Atlas covering 62 of the 170 species known to occur in the Palaearctic. Chromosome polymorphisms involving pericentric inversions and addition of extra C-banding regions have been found, as well as small B-chromosomes in a few species. In general, karyotypes have proved very useful in establishing the limits of individual species. Parthenogenesis involving triploidy has been found in two species. Karyotypes of experimentally produced hybrids have revealed irregularities in chromosome condensation.
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Outcomes of single-ventricle physiology in central South Africa. Cardiovasc J Afr 2023; 34:1-5. [PMID: 37647151 DOI: 10.5830/cvja-2023-043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 08/10/2023] [Indexed: 09/01/2023] Open
Abstract
INTRODUCTION Single-ventricle physiology is a critical cardiac condition requiring early diagnosis and intervention. The objectives of this study were to report on the management and outcomes of patients diagnosed with single-ventricle physiology in central South Africa. METHODS This study was a retrospective, observational analysis of patients presenting with single-ventricle physiology at the Universitas Academic Hospital in central South Africa between November 1997 and June 2021. RESULTS Patients were referred from the Free State (54%) and Northern Cape (29%) provinces and Lesotho. One hundred and fifty-four patients presented with single-ventricle physiology: 114 received interventions and 40 were not eligible for intervention. Patients presented for the first time at a median age of 34.5 days, with patients from nearby districts presenting within a few days of birth. However, patients from outlying areas presented much later. Eighty-seven patients received systemic-to-pulmonary artery shunting or pulmonary artery banding. Sixty-three patients proceeded to bidirectional Glenn procedures, and 30 patients (26%) had full palliation to Fontan. Twenty-one patients died after stage 1, six after the Glenn procedure and two after the Fontan procedure. Overall, 34 (29.8%) patients were lost to follow up. CONCLUSION Patients in our study presented late and follow up of these patients was a challenge. The highest mortality rate occurs during the first stage of palliation. Outcomes from this study are comparable to other sub-Saharan studies.
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Salvage of a megafistula causing high-output cardiac failure in a young adult with aneurysmorrhaphy and banding. J Vasc Access 2023; 24:832-835. [PMID: 34758668 DOI: 10.1177/11297298211055615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
We present the case of a 21-year-old male with significant lengthening and aneurysmal degeneration of his brachiocephalic arteriovenous fistula resulting in a megafistula and high-output cardiac failure. A computed tomography angiogram showed narrowing at the cephalic arch. Further evaluation during the operation revealed kinking and elongation of the fistula in addition to compression of the cephalic arch in the deltopectoral groove leading to outflow obstruction. The aneurysmal fistula was treated successfully with aneurysmorrhaphy of the remaining conduit and banding of the inflow. This case demonstrates a unique etiology of venous outflow obstruction for a fistula and describes the surgical approach to its treatment in a young patient suffering from cardiac failure.
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Estimating density of forest bats and their long-term trends in a climate refuge. Ecol Evol 2023; 13:e10215. [PMID: 37332522 PMCID: PMC10276525 DOI: 10.1002/ece3.10215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 06/06/2023] [Accepted: 06/08/2023] [Indexed: 06/20/2023] Open
Abstract
For many species, estimating density is challenging, but it is important for conservation planning and understanding the functional role of species. Bats play key ecological roles, yet little is known about their free-ranging density. We used a long-term banding study of four species caught in an extensively forested climate refuge and spatial capture-recapture models (SCR) to estimate density and its change over time. Between 1999 and 2020, there were 3671 captures of four bat species, which were all edge-space foragers. Recaptures represented 16% (n = 587) of all captures, of which 89 were between-trap-cluster movements. Closed spatial mark-recapture models estimated plausible densities that varied with elevation. Preferred elevations differed between species, with density averaging 0.63 ha-1 for Vespadelus darlingtoni (high elevation), 0.43 ha-1 for V. pumilus (low elevation), 0.19 ha-1 for Chalinolobus morio (high elevation), and 0.08 ha-1 for V. regulus (high elevation). Overall, densities were higher than most previous published estimates for bats. Forest disturbance history (past timber harvesting) had no detectable effect on density. Density also varied substantially across years, and although annual maximum temperature and rainfall were not supported in models, some time periods showed an apparent relationship between density and annual rainfall (+ve) and/or annual maximum temperature (-ve). The most notable change was an increase in the density of V. pumilus after 2013, which tracked an increase in annual temperature at the site, reflecting a warming climate. Bat densities in forests outside of climate refugia are likely to be more sensitive to climate change, but more studies are needed in different habitats and continents and outside climate refugia to place the densities we estimated into a broader context.
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Therapeutic Banding for Bleeding Duodenal Lymphangiectasias: A Novel Approach. ACG Case Rep J 2023; 10:e01087. [PMID: 37342653 PMCID: PMC10278729 DOI: 10.14309/crj.0000000000001087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 05/30/2023] [Indexed: 06/23/2023] Open
Abstract
With endoscopic advancements, the number of detected intestinal lymphangiectasias has been on the rise. They are generally considered benign and incidental; occasionally, these lesions carry complications, and best management options need to be established. Bleeding intestinal lymphangiectasias should be considered a rare cause in the differential diagnosis for gastrointestinal bleeding. References in the literature primarily indicate surgical treatment in these situations. In this study, we report an uncommon case of a man with esophageal adenocarcinoma who developed acute gastrointestinal bleeding from duodenal lymphangiectasias that were successfully banded.
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Therapeutic properties of glass-ionomer cements: Their application to orthodontic treatment. Aust Dent J 2021; 67:12-20. [PMID: 34762310 DOI: 10.1111/adj.12888] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/07/2021] [Accepted: 11/08/2021] [Indexed: 11/29/2022]
Abstract
Fluoride has been shown to be an effective agent in the prevention of caries during orthodontic treatment. Resin-modified glass-ionomer cements possess therapeutic anticariogenic properties acting as a fluoride reservoir and releasing fluoride into the environment, particularly at low pH where there is a threat of enamel demineralisation and white spot lesions (WSL's). Patient compliance to instructions in standard oral hygiene measures limits the success of caries prevention and the routine use of glass-ionomer cements can mitigate the lack of compliance, although RMGIC's are not a panacea against WSL's. The adhesion of GIC's to the enamel surface is a physicochemical bond rather than a mechanical bond which reduces the risk of iatrogenic damage to the enamel when bonding and debonding attachments. RMGIC's can be recommended as a bonding adhesive for all attachments but one needs to be selective when bonding molar attachments to avoid occlusal interferences as masticatory forces can be high in these areas.
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Evaluation of a two-season banding program to estimate and model migratory bird survival. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2021; 31:e02425. [PMID: 34296480 DOI: 10.1002/eap.2425] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 02/22/2021] [Accepted: 03/22/2021] [Indexed: 06/13/2023]
Abstract
The management of North American waterfowl is predicated on long-term, continental-scale banding implemented prior to the hunting season (i.e., July-September) and subsequent reporting of bands recovered by hunters. However, single-season banding and encounter operations have a number of characteristics that limit their application to estimating demographic rates and evaluating hypothesized limiting factors throughout the annual cycle. We designed and implemented a two-season banding program for American Black Ducks (Anas rubripes), Mallards (A. platyrhynchos), and hybrids in eastern North America to evaluate potential application to annual life cycle conservation and sport harvest management. We assessed model fit and compared estimates of annual survival among data types (i.e., pre-hunting season only [July-September], post-hunting season only [January-March], and two-season [pre- and post-hunting season]) to evaluate model assumptions and potential application to population modeling and management. There was generally high agreement between estimates of annual survival derived using two-season and pre-season only data for all age and sex cohorts. Estimates of annual survival derived from post-season banding data only were consistently higher for adult females and juveniles of both sexes. We found patterns of seasonal survival varied by species, age, and to a lesser extent, sex. Hunter recovered birds exhibited similar spatial distributions regardless of banding season suggesting banded samples were from the same population. In contrast, goodness-of-fit tests suggest this assumption was statistically violated in some regions and years. We conclude that estimates of seasonal and annual survival for Black Ducks and Mallards based on the two-season banding program are valid and accurate based on model fit statistics, similarity in survival estimates across data and models, and similarities in the distribution of recoveries. The two-season program provides greater precision and insight into the survival process and will improve the ability of researchers and managers to test competing hypotheses regarding population regulation resulting in more effective management.
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Acute and Long-Term Effects of Aortic Compliance Decrease on Central Hemodynamics: A Modeling Analysis. Front Physiol 2021; 12:701154. [PMID: 34381376 PMCID: PMC8350396 DOI: 10.3389/fphys.2021.701154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 07/06/2021] [Indexed: 11/25/2022] Open
Abstract
Aortic compliance is an important determinant of cardiac afterload and a contributor to cardiovascular morbidity. In the present study, we sought to provide in silico insights into the acute as well as long-term effects of aortic compliance decrease on central hemodynamics. To that aim, we used a mathematical model of the cardiovascular system to simulate the hemodynamics (a) of a healthy young adult (baseline), (b) acutely after banding of the proximal aorta, (c) after the heart remodeled itself to match the increased afterload. The simulated pressure and flow waves were used for subsequent wave separation analysis. Aortic banding induced hypertension (SBP 106 mmHg at baseline versus 152 mmHg after banding), which was sustained after left ventricular (LV) remodeling. The main mechanism that drove hypertension was the enhancement of the forward wave, which became even more significant after LV remodeling (forward amplitude 30 mmHg at baseline versus 60 mmHg acutely after banding versus 64 mmHg after remodeling). Accordingly, the forward wave’s contribution to the total pulse pressure increased throughout this process, while the reflection coefficient acutely decreased and then remained roughly constant. Finally, LV remodeling was accompanied by a decrease in augmentation index (AIx 13% acutely after banding versus −3% after remodeling) and a change of the central pressure wave phenotype from the characteristic Type A (“old”) to Type C (“young”) phenotype. These findings provide valuable insights into the mechanisms of hypertension and provoke us to reconsider our understanding of AIx as a solely arterial parameter.
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New Data on Comparative Cytogenetics of the Mouse-Like Hamsters ( Calomyscus Thomas, 1905) from Iran and Turkmenistan. Genes (Basel) 2021; 12:genes12070964. [PMID: 34202749 PMCID: PMC8304524 DOI: 10.3390/genes12070964] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 06/21/2021] [Accepted: 06/23/2021] [Indexed: 11/16/2022] Open
Abstract
The taxonomy of the genus Calomyscus remains controversial. According to the latest systematics the genus includes eight species with great karyotypic variation. Here, we studied karyotypes of 14 Calomyscus individuals from different regions of Iran and Turkmenistan using a new set of chromosome painting probes from a Calomyscus sp. male (2n = 46, XY; Shahr-e-Kord-Soreshjan-Cheshme Maiak Province). We showed the retention of large syntenic blocks in karyotypes of individuals with identical chromosome numbers. The only rearrangement (fusion 2/21) differentiated Calomyscus elburzensis, Calomyscus mystax mystax, and Calomyscus sp. from Isfahan Province with 2n = 44 from karyotypes of C. bailwardi, Calomyscus sp. from Shahr-e-Kord, Chahar Mahal and Bakhtiari-Aloni, and Khuzestan-Izeh Provinces with 2n = 46. The individuals from Shahdad tunnel, Kerman Province with 2n = 51-52 demonstrated non-centric fissions of chromosomes 4, 5, and 6 of the 46-chromosomal form with the formation of separate small acrocentrics. A heteromorphic pair of chromosomes in a specimen with 2n = 51 resulted from a fusion of two autosomes. C-banding and chromomycin A3-DAPI staining after G-banding showed extensive heterochromatin variation between individuals.
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Quantitative measures and 3D shell models reveal interactions between bands and their position on growing snail shells. Ecol Evol 2021; 11:6634-6648. [PMID: 34141246 PMCID: PMC8207382 DOI: 10.1002/ece3.7517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 03/10/2021] [Accepted: 03/17/2021] [Indexed: 11/10/2022] Open
Abstract
The nature of shell growth in gastropods is useful because it preserves the ontogeny of shape, colour, and banding patterns, making them an ideal system for understanding how inherited variation develops, is established and maintained within a population. However, qualitative scoring of inherited shell characters means there is a lack of knowledge regarding the mechanisms that control fine variation. Here, we combine empirical measures of quantitative variation and 3D modeling of shells to understand how bands are placed and interact. By comparing five-banded Cepaea individuals to shells lacking individual bands, we show that individual band absence has minor but significant impacts upon the position of remaining bands, implying that the locus controlling band presence/absence mainly acts after position is established. Then, we show that the shell grows at a similar rate, except for the region below the lowermost band. This demonstrates that wider bands of Cepaea are not an artifact of greater shell growth on the lower shell; they begin wider and grow at the same rate as other bands. Finally, we show that 3D models of shell shape and banding pattern, inferred from 2D photos using ShellShaper software, are congruent with empirical measures. This work therefore establishes a method that may be used for comparative studies of quantitative banding variation in snail shells, extraction of growth parameters, and morphometrics. In the future, studies that link the banding phenotype to the network of shell matrix proteins involved in biomineralization and patterning may ultimately aid in understanding the diversity of shell forms found in molluscs.
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Abdominal Aortic Neck Wrap for Refractory Type 1a Endoleak: A Case Series and a Novel Intraoperative Assessment Technique. Ann Vasc Dis 2021; 14:19-22. [PMID: 33786095 PMCID: PMC7991699 DOI: 10.3400/avd.oa.20-00152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Objective: Refractory type 1a endoleak after endovascular aneurysm repair (EVAR) can pose a significant challenge to surgeons and interventional radiologists. Continuous sac expansion results in aneurysm rupture and mortality. In such circumstances, an external infrarenal aortic wrap could serve as an essential and alternative solution. Methods: We assessed the application of an infrarenal aortic neck wrap for the treatment of refractory type 1a endoleak in n=6 consecutive patients along with the introduction of a novel assessment technique in order to assure their intraoperative success with no radiation exposure and contrast use. Results: The median sac expansion was 8.5 mm (interquartile range [IQR], 5-20 mm). The median neck diameter and length of the aortic neck were 23 mm (IQR, 18-25 mm) and 21 mm (IQR, 18-25 mm), respectively. The median length of follow-up post wrap is 24 months (IQR, 14-34 months). There was no associated mortality or morbidity and requirement for any further interventions. Conclusion: The study demonstrates that aortic wrapping for the treatment of refractory type 1a endoleak for any given neck diameter and length is safe, effective, and long lasting. The suggested novel intraoperative assessment technique contributes to the safety of the procedure by diminishing the need for intraoperative radiation exposure, contrast, and shorter operative time.
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Assessing the Pyloric Caeca and Distal Gut Microbiota Correlation with Flesh Color in Atlantic Salmon ( Salmo salar L., 1758). Microorganisms 2020; 8:microorganisms8081244. [PMID: 32824332 PMCID: PMC7464769 DOI: 10.3390/microorganisms8081244] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 08/08/2020] [Accepted: 08/12/2020] [Indexed: 01/19/2023] Open
Abstract
The Atlantic salmon (Salmo salar L., 1758) is a temperate fish species native to the northern Atlantic Ocean. The distinctive pink–red flesh color (i.e., pigmentation) significantly affects the market price. Flesh paleness leads to customer dissatisfaction, a loss of competitiveness, a drop in product value and, consequently, severe economic losses. This work extends our knowledge on salmonid carotenoid dynamics to include the interaction between the gut microbiota and flesh color. A significant association between the flesh color and abundance of specific bacterial communities in the gut microbiota suggests that color may be affected either by seeding resilient beneficial bacteria or by inhibiting the negative effect of pathogenic bacteria. We sampled 96 fish, which covered all phenotypes of flesh color, including the average color and the evenness of color of different areas of the fillet, at both the distal intestine and the pyloric caeca of each individual, followed by 16S rRNA sequencing at the V3-V4 region. The microbiota profiles of these two gut regions were significantly different; however, there was a consistency in the microbiota, which correlated with the flesh color. Moreover, the pyloric caeca microbiota also showed high correlation with the evenness of the flesh color (beta diversity index, PERMANOVA, p = 0.002). The results from the pyloric caeca indicate that Carnobacterium, a group belonging to the lactic acid bacteria, is strongly related to the flesh color and the evenness of the color between the flesh areas.
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Cytological markers used for identification and transfer of Aegilops spp. chromatin carrying valuable genes into cultivated forms of Triticum. COMPARATIVE CYTOGENETICS 2019; 13:41-59. [PMID: 30854169 PMCID: PMC6403195 DOI: 10.3897/compcytogen.v13i1.30673] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 01/30/2019] [Indexed: 05/26/2023]
Abstract
There are many reports describing chromosome structure, organization and evolution within goatgrasses (Aegilops spp.). Chromosome banding and fluorescence in situ hybridization techniques are main methods used to identify Aegilops Linnaeus, 1753 chromosomes. These data have essential value considering the close genetic and genomic relationship of goatgrasses with wheat (Triticumaestivum Linnaeus, 1753) and triticale (× Triticosecale Wittmack, 1899). A key question is whether those protocols are useful and effective for tracking Aegilops chromosomes or chromosome segments in genetic background of cultivated cereals. This article is a review of scientific reports describing chromosome identification methods, which were applied for development of prebreeding plant material and for transfer of desirable traits into Triticum Linnaeus, 1753 cultivated species. Moreover, this paper is a resume of the most efficient cytomolecular markers, which can be used to follow the introgression of Aegilops chromatin during the breeding process.
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An optical test to unveil twisting of birefringent crystals in spherulites. ROYAL SOCIETY OPEN SCIENCE 2019; 6:181215. [PMID: 30800372 PMCID: PMC6366204 DOI: 10.1098/rsos.181215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 11/27/2018] [Indexed: 06/09/2023]
Abstract
Helical conformations and structures are frequently observed in materials. The presence of helices at points of the unit cell of a crystal, on a larger size scale in the crystalline lattice or even in the microscopic structure of crystals, affects the chemico-physical properties of a solid and, hence, also interactions with light. Here, attention has been drawn to the geometrical properties of helices produced by a hypothetical torque of a transparent crystal, and optical properties of twisted crystals easily observed by a polarizing microscope have been discussed. Radially grown spherulites are obtained by most substances crystallized from melt. The circular arrangement of elongated crystals reflects the optical behaviour of each crystal and, because of the larger dimensions of spherulites, allows investigations otherwise hardly feasible on separate crystals. According to the torsional analysis of elongated bodies and the birefringence theory, information on the existence of helically shaped crystals can be deduced, as hereinafter explained, from the microscopic appearance and birefringence pattern of spherulites. Indeed, twisting decreases the birefringence throughout an elongated crystal and, therefore, also the birefringence of spherulites formed by twisted radial crystals is reduced.
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Frequency-modulated SSFP with radial sampling and subspace reconstruction: A time-efficient alternative to phase-cycled bSSFP. Magn Reson Med 2018; 81:1566-1579. [PMID: 30357904 DOI: 10.1002/mrm.27505] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 07/05/2018] [Accepted: 08/03/2018] [Indexed: 11/11/2022]
Abstract
PURPOSE A novel subspace-based reconstruction method for frequency-modulated balanced steady-state free precession (fmSSFP) MRI is presented. In this work, suitable data acquisition schemes, subspace sizes, and efficiencies for banding removal are investigated. THEORY AND METHODS By combining a fmSSFP MRI sequence with a 3D stack-of-stars trajectory, scan efficiency is maximized as spectral information is obtained without intermediate preparation phases. A memory-efficient reconstruction routine is implemented by introducing the low-frequency Fourier transform as a subspace which allows for the formulation of a convex reconstruction problem. The removal of banding artifacts is investigated by comparing the proposed acquisition and reconstruction technique to phase-cycled bSSFP MRI. Aliasing properties of different undersampling schemes are analyzed and water/fat separation is demonstrated by reweighting the reconstructed subspace coefficients to generate virtual spectral responses in a post-processing step. RESULTS A simple root-of-sum-of-squares combination of the reconstructed subspace coefficients yields high-SNR images with the characteristic bSSFP contrast but without banding artifacts. Compared to Golden-Angle trajectories, turn-based sampling schemes were superior in minimizing aliasing across reconstructed subspace coefficients. Water/fat separated images of the human knee were obtained by reweighting subspace coefficients. CONCLUSIONS The novel subspace-based fmSSFP MRI technique emerges as a time-efficient alternative to phase-cycled bSFFP. The method does not need intermediate preparation phases, offers high SNR and avoids banding artifacts. Reweighting of the reconstructed subspace coefficients allows for generating virtual spectral responses with applications to water/fat separation.
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Mitigation of near-band balanced steady-state free precession through-plane flow artifacts using partial dephasing. Magn Reson Med 2017; 79:2944-2953. [PMID: 28994486 DOI: 10.1002/mrm.26957] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 09/11/2017] [Accepted: 09/14/2017] [Indexed: 11/07/2022]
Abstract
PURPOSE To mitigate artifacts from through-plane flow at the locations of steady-state stopbands in balanced steady-state free precession (SSFP) using partial dephasing. METHODS A 60° range in the phase accrual during a TR was created over the voxel by slightly unbalancing the slice-select dephaser. The spectral profiles of SSFP with partial dephasing for various constant flow rates and during pulsatile flow were simulated to determine if partial dephasing decreases through-plane flow artifacts originating near SSFP dark bands while maintaining on-resonant signal. Simulations were then validated in a flow phantom. Lastly, phase-cycled SSFP cardiac cine images were acquired with and without partial dephasing in six subjects. RESULTS Partial dephasing decreased the strength and non-linearity of the dependence of the signal at the stopbands on the through-plane flow rate. It thus mitigated hyper-enhancement from out-of-slice signal contributions and transient-related artifacts caused by variable flow both in the phantom and in vivo. In six volunteers, partial dephasing noticeably decreased artifacts in all of the phase-cycled cardiac cine datasets. CONCLUSION Partial dephasing can mitigate the flow artifacts seen at the stopbands in balanced SSFP while maintaining the sequence's desired signal. By mitigating hyper-enhancement and transient-related artifacts originating from the stopbands, partial dephasing facilitates robust multiple-acquisition phase-cycled SSFP in the heart. Magn Reson Med 79:2944-2953, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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Removing vessel constriction on the embryonic heart results in changes in valve gene expression, morphology, and hemodynamics. Dev Dyn 2017; 247:531-541. [PMID: 28884516 DOI: 10.1002/dvdy.24588] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 08/30/2017] [Accepted: 09/01/2017] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The formation of healthy heart valves throughout embryonic development is dependent on both genetic and epigenetic factors. Hemodynamic stimuli are important epigenetic regulators of valvulogenesis, but the resultant molecular pathways that control valve development are poorly understood. Here we describe how the heart and valves recover from the removal of a partial constriction (banding) of the OFT/ventricle junction (OVJ) that temporarily alters blood flow velocity through the embryonic chicken heart (HH stage 16/17). Recovery is described in terms of 24- and 48-hr gene expression, morphology, and OVJ hemodynamics. RESULTS Collectively, these studies show that after 24 hr of recovery, important epithelial-mesenchymal transformation (EMT) genes TGFßRIII and Cadherin 11 (CDH11) transcript levels normalize return to control levels, in contrast to Periostin and TGFß,3 which remain altered. In addition, after 48 hr of recovery, TGFß3 and CDH11 transcript levels remain normalized, whereas TGFßRIII and Periostin are down-regulated. Analyses of OFT cushion volumes in the hearts show significant changes, as does the ratio of cushion to cell volume at 24 hr post band removal (PBR). Morphologically, the hearts show visible alteration following band removal when compared to their control age-matched counterparts. CONCLUSIONS Although some aspects of the genetic/cellular profiles affected by altered hemodynamics seem to be reversed, not all gene expression and cardiac growth normalize following 48 hr of band removal. Developmental Dynamics 247:531-541, 2018. © 2017 Wiley Periodicals, Inc.
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Concomitant Staple Aneurysmorrhaphy and Flow-Calibrated Arteriovenous Fistula Banding Over a Coronary Dilator to Treat Hand Steal Syndrome. Vasc Endovascular Surg 2017. [PMID: 28639917 DOI: 10.1177/1538574417699140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND True venous aneurysm formation can occur in patients with arteriovenous fistulas (AVFs) for hemodialysis but association with steal syndrome is uncommon. METHODS To describe a case of a patient on chronic hemodialysis through a right brachiocephalic fistula, who presents with associated steal syndrome and true arteriovenous access aneurysm. RESULTS A 34-year-old female with true AVF aneurysm presented with hand steal syndrome confirmed by noninvasive studies. The patient underwent a successful vein aneurysmorrhaphy with a commercially available stapler device and duplex ultrasound flow-calibrated banding. At 1-year follow-up, she remains pain free and the fistula remains functional with no recurrence of venous aneurysmal degeneration. CONCLUSION The use of a commercially available surgical stapler devices along with flow-calibrated banding guided by duplex ultrasound over a coronary dilator during the same operation is an elegant, efficacious, and a durable alternative for patients with hand steal syndrome and concomitant AVF aneurysms.
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Unexpected Internalization of a Pulmonary Artery Band in a Porcine Model of Tetralogy of Fallot. World J Pediatr Congenit Heart Surg 2016; 8:48-54. [PMID: 28033087 DOI: 10.1177/2150135116668828] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND We report our experience of an unexpected complication of internalization of a pulmonary artery (PA) band in the vascular lumen, which occurred in a chronic porcine model of repaired tetralogy of Fallot (TOF). METHODS Twelve piglets were divided into 3 groups: (1) TOF model animals (PA band plus pulmonary valvotomy, n = 4), (2) pulmonary insufficiency (PI) animals (pulmonary valvotomy, n = 4), and (3) control animals (n = 4). A nonabsorbable, coated braided polyester tape was used to perform the main pulmonary artery banding. Echocardiography was performed 4 months postoperatively. After each animal was euthanized, PA histological analysis was performed in animals with band internalization. RESULTS Significant postsurgical pulmonary regurgitation and right ventricular enlargement were present in the TOF and PI, compared with control animals, whereas no significant pulmonary stenosis was observed in TOF animals when compared with PI group. Postmortem examination of all TOF animals revealed the constricting band to be intact but partially internalized into the PA lumen, allowing blood flow around the stenosis. Histological sections of the banded PA in the area of internalization showed a significant disorganization of the medial layer, with significant scarring and fibrotic reaction surrounding the outside of the band and the presence of inflammatory cells suggesting a significant inflammatory response during band internalization. CONCLUSIONS Band internalization may occur after PA banding using a nonabsorbable, coated braided polyester tape in a chronic porcine model of repaired TOF. This unusual complication was likely due to the type of material used for banding.
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BLOOD GAS, LACTATE, AND HEMATOLOGY EFFECTS OF VENIPUNCTURE TIMING AND LOCATION AFTER MIST-NET CAPTURE OF MOURNING DOVES (ZENAIDA MACROURA), BOAT-TAILED GRACKLES (QUISCALUS MAJOR), AND HOUSE SPARROWS (PASSER DOMESTICUS). J Wildl Dis 2016; 52:S54-64. [PMID: 26845300 DOI: 10.7589/52.2s.s54] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Venous blood gas partial pressures, pH, bicarbonate and lactate concentrations, packed cell volume, white blood cell differential counts, and heterophil/lymphocyte ratios were measured from Mourning Doves (Zenaida macroura), Boat-tailed Grackles (Quiscalus major), and House Sparrows (Passer domesticus). Birds were bled promptly after mist-net capture and banding or following a targeted delay of 45-60 min, in order to assess the impacts of a brief holding period commonly practiced in large-scale bird banding operations. Additionally, effects of venipuncture location (basilic [=ulnar] vein versus jugular vein) were evaluated in male Boat-tailed Grackles sampled promptly after capture and banding. All comparisons were with unpaired samples; no birds were subjected to more than one venipuncture. All three species exhibited moderate improvements in blood gas and acid-base status after the delay, with reductions in lactate concentrations with or without concurrent increases in pH and bicarbonate. Boat-tailed Grackles exhibited an increased proportion of heterophils in the differential white blood cell count following a delay in sampling, suggestive of a stress leukogram. There were no significant differences between basilic and jugular venipuncture results from male Boat-tailed Grackles. Most metabolic, respiratory, and acid-base alterations were minor, but a small number of birds exhibited values (e.g., temperature-corrected pH <7.3, lactate >10 mmol/L) that could be of concern if combined with other adverse conditions. For such birds, a short delay between capture and processing could benefit their blood gas and acid-base status, although loss of time foraging or feeding young and greater activation of the hypophyseal-pituitary-adrenal axis are additional considerations.
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Banding of Nonrestrictive Large Hypertensive Aortopulmonary Collaterals in Patients With Ventricular Septal Defect and Pulmonary Atresia Presenting in Suboptimal Condition. World J Pediatr Congenit Heart Surg 2016; 7:626-9. [PMID: 27587500 DOI: 10.1177/2150135116658453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 05/31/2016] [Indexed: 11/15/2022]
Abstract
Infants with pulmonary atresia and nonrestrictive ventricular septal defect with large hypertensive aortopulmonary collaterals demand early surgical intervention. This presentation in the extremely low-weight child or in the moribund septic child may preclude single-stage repair even if anatomically suited. We propose that such infants may be temporized by means of banding of individual aortopulmonary collaterals as a means of bridging to a second-stage complete repair. Two such cases are presented.
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A Prospective Randomized Study on the Risk of Bacteremia in Banding versus Sclerotherapy of Esophageal Varices. Front Med (Lausanne) 2016; 3:16. [PMID: 27200352 PMCID: PMC4852182 DOI: 10.3389/fmed.2016.00016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 04/11/2016] [Indexed: 01/22/2023] Open
Abstract
Background Esophageal variceal banding may be less likely to cause bacteremia than sclerotherapy. The existing data about the frequency of bacteremia after esophageal variceal banding are conflicting, and few studies include both banding and sclerotherapy. Aims We conducted a prospective randomized controlled trial to compare the frequency of bacteremia after esophageal variceal banding and sclerotherapy. Methods Over a 2-year period, patients with liver disease admitted for upper gastrointestinal bleeding or for outpatient elective variceal therapy were enrolled. New patients were randomized preprocedure to either banding or sclerotherapy, and subsequent sessions utilized the initial procedure. The groups consisted of banding, sclerotherapy, and endoscopy without variceal therapy. Subjects underwent endoscopy by one out of three gastroenterologists. Blood cultures were obtained 5 min before and 30 min after endoscopy to check for bacteremia. Results Postendoscopic blood cultures were positive following 4 out of 139 (2.9%) sessions: 1 sclerotherapy and 3 control sessions. All postendoscopic positive blood cultures were found following emergency sessions (4/92, 4.3%). One pre-endoscopic blood culture was positive in a patient with emergency banding. The rates of positive postendoscopic blood cultures among groups with emergency banding (0/22, 0%), emergency sclerotherapy (1/41, 2.3%), and emergency control (3/29, 10.3%) were not significantly different. Postendoscopic positive blood cultures were not found after elective sessions with either banding or sclerotherapy. Conclusions Postendoscopic bacteremia was infrequent following emergency endoscopy in patients with esophageal variceal bleeding. Bacteremia was not found after esophageal variceal banding, although this was not significantly less frequent than after sclerotherapy. Postendoscopic bacteremia was not associated with elective variceal therapy.
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Abstract
BACKGROUND Microleakage may cause tooth sensitivity, secondary caries, discoloration and even failure of the restoration. In order to overcome these potential problems, materials that are able to bind to the tooth structure have been developed, such as composite resin and glass ionomer cement. The purpose of the study was to compare microleakage arising from amalgam (Am), composite resin (CR), glass ionomer (GI), Ketac-Silver (KS), and GI filling with banding (GI+B) when these materials are used for class II restoration of a primary molar. METHODS Fifty primary molars were collected and class II cavities were prepared on each tooth. The teeth were randomly divided into five groups (Am, CR, GI, KS, and GI+B), each of which received a different material as part of the restoration. The restored teeth then underwent 100 cycles of thermocycling that consisted of 55°C for 30 seconds, 19°C for 20 seconds, and 5°C for 30 seconds. The teeth were then immersed in 0.5% basic fuchsin solution for 24 hours. Afterwards, the teeth were embedded and sectioned mesiodistally through the center of each restoration. Dye penetration associated with the occlusal and cervical margins of each restoration was then assessed. RESULTS Cervical leakage was greater than occlusal leakage in the CR, GI and KS groups (p < 0.05). When leakage on occlusal margin was examined, however, the Am group showed greater leakage than the CR, GI, and GI+B groups (p < 0.05). When leakage on the cervical margin was examined, the Am group showed greater leakage than the GI and GI+B groups, while the KS group showed greater leakage than the GI+B group (p < 0.05). CONCLUSION Restorations using GI and GI+B indicated that these materials performed better than the other materials in this study overall. However, none of the materials were entirely devoid of leakage.
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ASSESSMENT OF THE RATES OF INJURY AND MORTALITY IN WATERFOWL CAPTURED WITH FIVE METHODS OF CAPTURE AND TECHNIQUES FOR MINIMIZING RISKS. J Wildl Dis 2016; 52:S86-95. [PMID: 26845303 DOI: 10.7589/52.2s.s86] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Swan pipes, duck decoys, cage traps, cannon netting, and roundups are widely used to capture waterfowl in order to monitor populations. These methods are often regulated in countries with national ringing or banding programs and are considered to be safe, and thus justifiable given the benefits to conservation. However, few published studies have addressed how frequently injuries and mortalities occur, or the nature of any injuries. In the present study, rates of mortality and injury during captures with the use of these methods carried out by the Wildfowl & Wetlands Trust as part of conservation programs were assessed. The total rate of injury (including mild dermal abrasions) was 0.42% across all species groups, whereas total mortality was 0.1% across all capture methods. Incidence of injury varied among species groups (ducks, geese, swans, and rails), with some, for example, dabbling ducks, at greater risk than others. We also describe techniques used before, during, and after a capture to reduce stress and injury in captured waterfowl. Projects using these or other capture methods should monitor and publish their performance to allow sharing of experience and to reduce risks further.
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Abstract
We describe a simple technique we use in our institution during surgery for aortic aneurysms to reduce tension on the anastomosis when there is a discrepancy between the remnant portion of the native aorta and the vascular prosthesis.
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Use of a new implantable adjustable pulmonary artery banding device: a report of two patients. THE JOURNAL OF EXTRA-CORPOREAL TECHNOLOGY 2008; 40:65-67. [PMID: 18389668 PMCID: PMC4680659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Pulmonary artery banding (PAB) is a method for reducing pulmonary artery blood flow and pressure by tying a surgical band around the main pulmonary artery (MPA). Originally, the procedure was primarily performed to palliate intracardiac left to right shunts for ventricular septal defects (VSDs). Currently, the use of PAB has expanded to allow it to be used in ventricular training, prior to total corrective surgery. At the Rigshospitalet, Copenhagen, Denmark we have been trying a new device. The Flo-Watch PAB implant (EndoArt, Lausanne, Switzerland) is only currently available within certain European countries. The device is a mechanical PAB that allows noninvasive adjustment of the band post implantation, in an outpatient clinic. This has multiple advantages, not only in terms of convenience for the patient, and the reduced risk of multiple surgical interventions, but also from a financial standpoint to the health system. We would like to present our findings and comment on the use of the device in this report.
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Diagnosis and management of upper gastrointestinal bleeding. DEUTSCHES ARZTEBLATT INTERNATIONAL 2008; 105:85-94. [PMID: 19633792 DOI: 10.3238/arztebl.2008.0085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2007] [Accepted: 12/17/2007] [Indexed: 01/27/2023]
Abstract
INTRODUCTION Upper gastrointestinal (GI) bleeding is defined as bleeding proximal to ligament of Treitz. Its clinical presentations are hematemesis, melena stool, or even fresh bleeding per rectum. This paper reviews the diagnosis and treatment of upper GI bleeding. METHODS Selective literature review. RESULTS Common causes of upper GI bleeding are peptic ulcer disease, bleeding from gastroesophageal varices, angiodysplasias, and Mallory-Weiss lesions. The most important diagnostic intervention is endoscopy, which allows therapeutic interventions if needed. Peptic ulcer disease is treated endoscopically with injection therapy and endoclips. Acute bleeding from oesophageal varices is treated by banding. Endoscopic treatment is accompanied by medical treatment with proton pump inhibitors for the treatment of peptic ulcer disease, and vasoactive drugs for the treatment of bleeding oesophageal varices. DISCUSSION Modern endoscopy affords good localization of the bleeding site and successful treatment for most patients with upper GI bleeding.
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