800 research outputs found

    Analysis of post-transplant lymphoproliferative disorder (PTLD) outcomes with Epstein-Barr virus (EBV) assessments-a single tertiary referral center experience and review of literature

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    Post-transplant lymphoproliferative disorders (PTLDs) are lymphoid or plasmacytic proliferations ranging from polyclonal reactive proliferations to overt lymphomas that develop as consequence of immunosuppression in recipients of solid organ transplantation (SOT) or allogeneic bone marrow/hematopoietic stem cell transplantation. Immunosuppression and Epstein-Barr virus (EBV) infection are known risk factors for PTLD. Patients with documented histopathologic diagnosis of primary PTLD at our institution between January 2000 and October 2019 were studied. Sixty-six patients with PTLD following SOT were followed for a median of 9.0 years. The overall median time from transplant to PTLD diagnosis was 5.5 years, with infant transplants showing the longest time to diagnosis at 12.0 years, compared to pediatric and adolescent transplants at 4.0 years and adult transplants at 4.5 years. The median overall survival (OS) was 19.0 years. In the monomorphic diffuse large B-cell (M-DLBCL-PTLD) subtype, median OS was 10.7 years, while median OS for polymorphic subtype was not yet reached. There was no significant difference in OS in patients with M-DLBCL-PTLD stratified by quantitative EBV viral load over and under 100,000 copies/mL at time of diagnosis, although there was a trend towards worse prognosis in those with higher copies

    HBF4 Catalysed Nucleophilic Substitutions of Propargylic Alcohols

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    The activity of HBF4 (aqueous solution) as a catalyst in propargylation reactions is presented. Diverse types of nucleophiles were employed in order to form new C–O, C–N and C–C bonds in technical acetone and in air. Good to excellent yields and good chemoselectivities were obtained using low acid loading (typically 1 mol-%) under simple reaction conditions

    Scientific considerations for acidification monitoring in the US Mid-Atlantic Region

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    Coastal and ocean acidification has the potential to cause significant environmental and societal impacts. Monitoring carbonate chemistry parameters over spatial and temporal scales is challenging, especially with limited resources. A lack of monitoring data can lead to a limited understanding of real-world conditions. Without such data, robust experimental and model design is challenging, and the identification and understanding of episodic acidification events is nearly impossible. We present considerations for resource managers, academia, and industry professionals who are currently developing acidification monitoring programs in the Mid-Atlantic region. We highlight the following considerations for deliberation: 1) leverage existing infrastructure to include multiple carbonate chemistry parameters as well as other water quality measurements, 2) direct monitoring efforts in subsurface waters rather than limiting monitoring to surface waters, 3) identify the best available sensor technology for long-term, in-situ monitoring, 4) monitor across a salinity gradient to account for the complexity of estuarine, coastal, and ocean environments, and identify potential areas of enhanced vulnerability, 5) increase sampling frequency to capture variability, 6) consider other drivers (e.g., freshwater discharge, nutrients, physiochemical parameters) that may affect acidification, and 7) conduct or continue monitoring in specific ecological and general regions that may have enhanced vulnerability. Through the incorporation of these considerations, individual monitoring programs can more efficiently and effectively leverage resources and build partnerships for a more comprehensive data collection in the region. While these considerations focus on the Mid-Atlantic region), similar strategies can be used to leverage resources in other locations

    Expression of the mouse α1(II) collagen gene is not restricted to cartilage during development

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    The mouse alpha 1(II) collagen gene has been isolated and a 5' portion of the gene which has low homology to other collagen genes was used to study the pattern of expression during mouse embryogenesis. In situ hybridization studies show that in the mouse, like the chick, alpha 1(II) collagen is expressed in chondrogenic tissues in advance of chondrocyte differentiation. The gene is expressed early in embryogenesis at 9.5 days both in the cranial mesenchyme destined for the chondrocranium, and the sclerotome of the somites, and at 12.5 days in the primordia of the hyoid and the laryngeal cartilage. Type II collagen gene transcripts were found in all the chondrogenic tissues of the axial and appendicular skeleton until the onset of endochondral ossification. Expression of alpha 1(II) collagen mRNA was also observed in non-chondrogenic tissues such as the notochord which may be responsible for inducing chondrogenesis in somitic mesoderm, neural retina, the corneal and conjunctival epithelia and sclera of the developing eye. Expression in the tail tendon was late, at 16.5-18.5 days. Transient expression was also found in the heart at 9.5-12.5 days, the epidermis at 10.5-14.5 days, the calvarial mesenchyme at 12.5-16.5 days, the inner ear at 14.5 days and the fetal brain from 9.5-14.5 days. Within the neural tube, alpha 1(II) collagen mRNA was localized in the proliferative ventricular cells of the forebrain and midbrain of 9.5- to 10.5-day embryos. Subsequently, transcription of the alpha 1(II) collagen gene was confined to restricted areas of the rhombencephalic basal plate, the ventricular layer of the hindbrain and the cervical spinal cord. These examples of expression of the type II collagen gene in the developing nervous system seem to suggest that active transcription of this gene might be associated with early stages of neuroblast differentiation. Type II collagen may therefore have additional roles in development unrelated to chondrogenesis.published_or_final_versio

    Real-world COVID-19 vaccine effectiveness against the Omicron BA.2 variant in a SARS-CoV-2 infection-naive population

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    The SARS-CoV-2 Omicron variant has demonstrated enhanced transmissibility and escape of vaccine-derived immunity. Although first-generation vaccines remain effective against severe disease and death, robust evidence on vaccine effectiveness (VE) against all Omicron infections, irrespective of symptoms, remains sparse. We used a community-wide serosurvey with 5,310 subjects to estimate how vaccination histories modulated risk of infection in infection-naive Hong Kong during a large wave of Omicron BA.2 epidemic in January-July 2022. We estimated that Omicron infected 45% (41-48%) of the local population. Three and four doses of BNT162b2 or CoronaVac were effective against Omicron infection 7 days after vaccination (VE of 48% (95% credible interval 34-64%) and 69% (46-98%) for three and four doses of BNT162b2, respectively; VE of 30% (1-66%) and 56% (6-97%) for three and four doses of CoronaVac, respectively). At 100 days after immunization, VE waned to 26% (7-41%) and 35% (10-71%) for three and four doses of BNT162b2, and to 6% (0-29%) and 11% (0-54%) for three and four doses of CoronaVac. The rapid waning of VE against infection conferred by first-generation vaccines and an increasingly complex viral evolutionary landscape highlight the necessity for rapidly deploying updated vaccines followed by vigilant monitoring of VE

    Rapid aneuploidy testing (knowing less) versus traditional karyotyping (knowing more) for advanced maternal age: What would be missed, who should decide?

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    Objectives The application of rapid aneuploidy testing as a stand-alone approach in prenatal diagnosis is much debated. The major criticism of this targeted approach is that it will not detect other chromosomal abnormalities that will be picked up by traditional karyotyping. This study aimed to study the nature of such chromosomal abnormalities and whether parents would choose to terminate affected pregnancies. Design Retrospective study on a cytogenetic database. Setting Eight public hospitals in Hong Kong. Participants The karyotype results of 19 517 amniotic fluid cultures performed for advanced maternal age (≥35 years) from 1997 to 2002 were classified according to whether they were detectable by rapid aneuploidy testing. The outcomes of pregnancies with abnormal karyotypes were reviewed from patient records. Results In all, 333 (1.7%) amniotic fluid cultures yielded abnormal karyotypes; 175 (52.6%) of these were detected by rapid aneuploidy testing, and included trisomy 21 (n=94, 28.2%), trisomy 18 or 13 (n=21, 6.3%), and sex chromosome abnormalities (n=60, 18.0%). The other 158 (47.4%) chromosomal abnormalities were not detectable by rapid aneuploidy testing, of which 63 (18.9%) were regarded to be of potential clinical significance and 95 (28.5%) of no clinical significance. Pregnancy outcomes in 327/333 (98.2%) of these patients were retrieved. In total, 143 (42.9%) of these pregnancies were terminated: 93/94 (98.9%) for trisomy 21, 20/21 (95.2%) for trisomy 18 or 13, 19/60 (31.7%) for sex chromosome abnormalities, and 11/63 (17.5%) for other chromosomal abnormalities with potential clinical significance. There were no terminations in the 95 pregnancies in which karyotyping results were regarded to be of no clinical significance. Conclusions 'Knowing less' by the rapid aneuploidy stand-alone testing could miss about half of all chromosomal abnormalities detectable by amniocentesis performed for advanced maternal age. Findings from two fifths of the latter were of potential clinical significance, and the parents chose to terminate one out of six of the corresponding pregnancies. If both techniques are available, parents could have enhanced autonomy to choose.published_or_final_versio

    An Alternative Perturbation Procedure of Multiple Scales for Nonlinear Dynamics Systems

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    An alternative perturbation procedure of multiple scales is presented in this paper which is capable of treating various periodic and almost periodic steady-state vibrations including combination resonance of nonlinear systems with multiple degrees-of-freedom. This procedure is a generalization of th

    Singaporean mothers' perception of their three-year-old child's weight status: A cross-sectional study

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    Singapore National Research FoundationFull Author List as below: Cheng T.S.; Cheng T.; Loy S.; Cheung Y.; Chan J.; Tint M.; Godfrey K.; Gluckman P.; Kwek K.; Saw S.; Chong Y.; Lee Y.; Yap F.; Lek N.; Sheppard A.; Chinnadurai A.; Goh A.; Rifkin-Graboi A.; Qiu A.; Biswas A.; Lee B.; Broekman B.; Quah B.; Shuter B.; Chng C.; Ngo C.; Hsu S.; Bong C.; Henry C.; Chee C.; Fok D.; Yeo G.; Inskip H.; Chen H.; Van Bever H.; Magiati I.; Wong I.; Lau I.; Kapur J.; Richmond J.; Holbrook J.; Gooley J.; Tan K.; Niduvaje K.; Singh L.; Su L.; Daniel L.; Shek L.; Fortier M.; Hanson M.; Chong M.; Rauff M.; Chua M.; Meaney M.; Teoh O.; Wong P.; Agarwal P.; Van Dam R.; Rebello S.; Chong S.; Cai S.; Soh S.; Lim S.; Rajadurai V.; Stunkel W.; Han W.; Pang W.; Goh Y.; Chan Y.</p
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