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1.
Animals (Basel) ; 14(11)2024 May 31.
Article in English | MEDLINE | ID: mdl-38891700

ABSTRACT

This study aimed to characterize and describe the different lymphoma types and anatomical forms in cats in Hong Kong. The clinical and histopathological data of cats diagnosed with lymphoma by cytology and/or histopathology were collected from a large diagnostic laboratory in Hong Kong. In total, 444 cats were diagnosed with lymphoma over four years (2019-2022). Like other countries where there is a low prevalence of FeLV infection, the predominant form of lymphoma was gastrointestinal (abdominal). Nasopharyngeal and peripheral nodal lymphoma were the second and third most common forms of lymphoma. The large cell/high-grade lymphoma type was much more common than the low-grade/small cell lymphoma in the study population. Domestic short hair was the most commonly affected breed in our study (n = 259/444). Among the cats with identified T/B-cell status, B-cell lymphoma (n = 61/81) prevailed as the most common phenotype. This study describes and characterizes the different types of feline lymphoma in cats in Hong Kong, adding valuable information to the body of knowledge.

2.
Pharmaceutics ; 15(7)2023 Jul 17.
Article in English | MEDLINE | ID: mdl-37514151

ABSTRACT

Large-area craniofacial defects remain a challenge for orthopaedists, hastening the need to develop a facile and safe tissue engineering strategy; osteoconductive material and a combination of optimal growth factors and microenvironment should be considered. Faced with the unmet need, we propose that abundant cytokines and chemokines can be secreted from the bone defect, provoking the infiltration of endogenous stem cells to assist bone regeneration. We can provide a potent mRNA medicine cocktail to promptly initiate the formation of bone templates, osteogenesis, and subsequent bone matrix deposition via endochondral ossification, which may retard rapid fibroblast infiltration and prevent the formation of atrophic non-union. We explored the mutual interaction of BMP2 and TGFß3 mRNA, both potent chondrogenic factors, on inducing endochondral ossification; examined the influence of in vitro the transcribed polyA tail length on mRNA stability; prepared mRNA nanomedicine using a PEGylated polyaspartamide block copolymer loaded in a gelatin sponge and grafted in a critical-sized calvarial defect; and evaluated bone regeneration using histological and µCT examination. The BMP2 and TGFß3 composite mRNA nanomedicine resulted in over 10-fold new bone volume (BV) regeneration in 8 weeks than the BMP2 mRNA nanomedicine administration alone, demonstrating that the TGFß3 mRNA nanomedicine synergistically enhances the bone's formation capability, which is induced by BMP2 mRNA nanomedicine. Our data demonstrated that mRNA-medicine-mediated endochondral ossification provides an alternative cell-free tissue engineering methodology for guiding craniofacial defect healing.

3.
Mol Breed ; 43(6): 45, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37313223

ABSTRACT

Current combined challenges of rising food demand, climate change and farmland degradation exert enormous pressure on agricultural production. Worldwide soil salinization, in particular, necessitates the development of salt-tolerant crops. Soybean, being a globally important produce, has its genetic resources increasingly examined to facilitate crop improvement based on functional genomics. In response to the multifaceted physiological challenge that salt stress imposes, soybean has evolved an array of defences against salinity. These include maintaining cell homeostasis by ion transportation, osmoregulation, and restoring oxidative balance. Other adaptations include cell wall alterations, transcriptomic reprogramming, and efficient signal transduction for detecting and responding to salt stress. Here, we reviewed functionally verified genes that underly different salt tolerance mechanisms employed by soybean in the past two decades, and discussed the strategy in selecting salt tolerance genes for crop improvement. Future studies could adopt an integrated multi-omic approach in characterizing soybean salt tolerance adaptations and put our existing knowledge into practice via omic-assisted breeding and gene editing. This review serves as a guide and inspiration for crop developers in enhancing soybean tolerance against abiotic stresses, thereby fulfilling the role of science in solving real-life problems. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01383-3.

4.
Plant Genome ; 16(4): e20316, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36890704

ABSTRACT

The growth and development of plants are the result of the interplay between the internal developmental programming and plant-environment interactions. Gene expression regulations in plants are made up of multi-level networks. In the past few years, many studies were carried out on co- and post-transcriptional RNA modifications, which, together with the RNA community, are collectively known as the "epitranscriptome." The epitranscriptomic machineries were identified and their functional impacts characterized in a broad range of physiological processes in diverse plant species. There is mounting evidence to suggest that the epitranscriptome provides an additional layer in the gene regulatory network for plant development and stress responses. In the present review, we summarized the epitranscriptomic modifications found so far in plants, including chemical modifications, RNA editing, and transcript isoforms. The various approaches to RNA modification detection were described, with special emphasis on the recent development and application potential of third-generation sequencing. The roles of epitranscriptomic changes in gene regulation during plant-environment interactions were discussed in case studies. This review aims to highlight the importance of epitranscriptomics in the study of gene regulatory networks in plants and to encourage multi-omics investigations using the recent technical advancements.


Subject(s)
Gene Expression Regulation , Transcriptome , RNA/chemistry , RNA Processing, Post-Transcriptional , Gene Regulatory Networks
5.
Nat Biomed Eng ; 6(10): 1105-1117, 2022 10.
Article in English | MEDLINE | ID: mdl-36229661

ABSTRACT

Treatments for osteoarthritis would benefit from the enhanced visualization of injured articular cartilage and from the targeted delivery of disease-modifying drugs to it. Here, by using ex vivo human osteoarthritic cartilage and live rats and minipigs with induced osteoarthritis, we report the application of collagen-binding peptides, identified via phage display, that are home to osteoarthritic cartilage and that can be detected via magnetic resonance imaging when conjugated with a superparamagnetic iron oxide. Compared with the use of peptides with a scrambled sequence, hyaluronic acid conjugated with the collagen-binding peptides displayed enhanced retention in osteoarthritic cartilage and better lubricated human osteoarthritic tissue ex vivo. Mesenchymal stromal cells encapsulated in the modified hyaluronic acid and injected intra-articularly in rats showed enhanced homing to osteoarthritic tissue and improved its regeneration. Molecular docking revealed WXPXW as the consensus motif that binds to the α1 chain of collagen type XII. Peptides that specifically bind to osteoarthritic tissue may aid the diagnosis and treatment of osteoarthritic joints.


Subject(s)
Cartilage, Articular , Osteoarthritis , Animals , Humans , Rats , Swine , Cartilage, Articular/diagnostic imaging , Cartilage, Articular/metabolism , Hyaluronic Acid/metabolism , Lubrication , Collagen Type XII/metabolism , Molecular Docking Simulation , Swine, Miniature , Osteoarthritis/metabolism , Regeneration , Peptides/metabolism
6.
Biomedicines ; 10(3)2022 Feb 26.
Article in English | MEDLINE | ID: mdl-35327357

ABSTRACT

(1) Background: Inexplicable low back and neck pain frequently results from spinal disc degeneration with an imbalanced intervertebral disc (IVD) cell homeostasis. We hypothesize that introducing MSC expressing a sustained cartilage-anabolic factor in the IVD may stimulate the mucoid materials secreted from the IVD cells, promote the MSC's chondrogenesis and maintain the hydration content providing mechanical strength to decelerate the disc degeneration progression; (2) Methods: This study expressed a cartilage-anabolic factor runx1 by a baculoviral vector (BV) transduced MSCs through a Cre/LoxP gene editing and recombination system for sustained recombinant runx1 transcription factor production. The Cre/LoxP BV modified MSCs were encapsulated by hyaluronan hydrogel, due to its' vital composition in ECM of a healthy disc and transplanted to a punctured coccygeal disc in rats through micro-injection, followed by X-ray radiography and histological analysis at the 4- and 12-weeks post-transplantation; (3) Results: Data reveals the Cre/LoxP BV system-mediated long-termed runx1 gene expression, possessing good biosafety characteristics in the in vitro cell transduction and in vivo MSCs transplantation, and maintained superior hydration content in the disc than that of mock transduced MSCs; (4) Conclusions: This proof-of-concept study fulfills the need of implanting therapeutic cells accompanied with microinjection in the disc, such as a discography and paves a road to manufacture composite hyaluronan, such as peptide modified hyaluronan as an MSC carrier for IVD regeneration in the future study.

7.
JMIR Med Inform ; 10(1): e29458, 2022 Jan 31.
Article in English | MEDLINE | ID: mdl-35099393

ABSTRACT

BACKGROUND: Intravenous (IV) vancomycin is used in the treatment of severe infection in neonates. However, its efficacy is compromised by elevated risks of acute kidney injury. The risk is even higher among neonates admitted to the neonatal intensive care unit (NICU), in whom the pharmacokinetics of vancomycin vary widely. Therapeutic drug monitoring is an integral part of vancomycin treatment to balance efficacy against toxicity. It involves individual dose adjustments based on the observed serum vancomycin concentration (VCs). However, the existing trough-based approach shows poor evidence for clinical benefits. The updated clinical practice guideline recommends population pharmacokinetic (popPK) model-based approaches, targeting area under curve, preferably through the Bayesian approach. Since Bayesian methods cannot be performed manually and require specialized computer programs, there is a need to provide clinicians with a user-friendly interface to facilitate accurate personalized dosing recommendations for vancomycin in critically ill neonates. OBJECTIVE: We used medical data from electronic health records (EHRs) to develop a popPK model and subsequently build a web-based interface to perform model-based individual dose optimization of IV vancomycin for NICU patients in local medical institutions. METHODS: Medical data of subjects prescribed IV vancomycin in the NICUs of Prince of Wales Hospital and Queen Elizabeth Hospital in Hong Kong were extracted from EHRs, namely the Clinical Information System, In-Patient Medication Order Entry, and electronic Patient Record. Patient demographics, such as body weight and postmenstrual age (PMA), serum creatinine (SCr), vancomycin administration records, and VCs were collected. The popPK model employed a 2-compartment infusion model. Various covariate models were tested against body weight, PMA, and SCr, and were evaluated for the best goodness of fit. A previously published web-based dosing interface was adapted to develop the interface in this study. RESULTS: The final data set included EHR data extracted from 207 subjects, with a total of 689 VCs measurements. The final model chosen explained 82% of the variability in vancomycin clearance. All parameter estimates were within the bootstrapping CIs. Predictive plots, residual plots, and visual predictive checks demonstrated good model predictability. Model approximations showed that the model-based Bayesian approach consistently promoted a probability of target attainment (PTA) above 75% for all subjects, while only half of the subjects could achieve a PTA over 50% with the trough-based approach. The dosing interface was developed with the capability to optimize individual doses with the model-based empirical or Bayesian approach. CONCLUSIONS: Using EHRs, a satisfactory popPK model was verified and adopted to develop a web-based individual dose optimization interface. The interface is expected to improve treatment outcomes of IV vancomycin for severe infections among critically ill neonates. This study provides the foundation for a cohort study to demonstrate the utility of the new approach compared with previous dosing methods.

8.
Int J Mol Sci ; 23(1)2022 Jan 05.
Article in English | MEDLINE | ID: mdl-35008997

ABSTRACT

Vertebral disc degenerative disease (DDD) affects millions of people worldwide and is a critical factor leading to low back and neck pain and consequent disability. Currently, no strategy has addressed curing DDD from fundamental aspects, because the pathological mechanism leading to DDD is still controversial. One possible mechanism points to the homeostatic status of extracellular matrix (ECM) anabolism, and catabolism in the disc may play a vital role in the disease's progression. If the damaged disc receives an abundant amount of cartilage, anabolic factors may stimulate the residual cells in the damaged disc to secrete the ECM and mitigate the degeneration process. To examine this hypothesis, a cartilage anabolic factor, Runx1, was expressed by mRNA through a sophisticated polyamine-based PEG-polyplex nanomicelle delivery system in the damaged disc in a rat model. The mRNA medicine and polyamine carrier have favorable safety characteristics and biocompatibility for regenerative medicine. The endocytosis of mRNA-loaded polyplex nanomicelles in vitro, mRNA delivery efficacy, hydration content, disc shrinkage, and ECM in the disc in vivo were also examined. The data revealed that the mRNA-loaded polyplex nanomicelle was promptly engulfed by cellular late endosome, then spread into the cytosol homogeneously at a rate of less than 20 min post-administration of the mRNA medicine. The mRNA expression persisted for at least 6-days post-injection in vivo. Furthermore, the Runx1 mRNA delivered by polyplex nanomicelles increased hydration content by ≈43% in the punctured disc at 4-weeks post-injection (wpi) compared with naked Runx1 mRNA administration. Meanwhile, the disc space and ECM production were also significantly ameliorated in the polyplex nanomicelle group. This study demonstrated that anabolic factor administration by polyplex nanomicelle-protected mRNA medicine, such as Runx1, plays a key role in alleviating the progress of DDD, which is an imbalance scenario of disc metabolism. This platform could be further developed as a promising strategy applied to regenerative medicine.


Subject(s)
Core Binding Factor Alpha 2 Subunit/genetics , Gene Transfer Techniques , Intervertebral Disc Degeneration/genetics , Intervertebral Disc Degeneration/therapy , Micelles , Nanoparticle Drug Delivery System , RNA, Messenger/administration & dosage , Animals , Disease Models, Animal , Endocytosis , Gene Expression , Genetic Therapy , Intervertebral Disc/diagnostic imaging , Intervertebral Disc/metabolism , Intervertebral Disc/pathology , Intervertebral Disc Degeneration/diagnostic imaging , Intervertebral Disc Degeneration/pathology , Male , Molecular Imaging , Nanomedicine , Rats , Transgenes , Treatment Outcome , X-Ray Microtomography
9.
One Health ; 13: 100300, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34409148

ABSTRACT

In this study, a phylogenic analysis was performed on pathogens previously identified in Hong Kong wet markets' cutting boards. Phylogenetic comparisons were made between phylotypes obtained in this study and environmental and clinical phylotypes for establishing the possible origin of selected bacterial species isolated from wet market cutting board ecosystems. The results reveal a strong relationship between wet market bacterial assemblages and environmental and clinically relevant phylotypes. However, our poor knowledge of potential cross-contamination sources within these wet markets is further exacerbated by failing to determine the exact or presumed origin of its identified pathogens. In this study, several clinically relevant bacterial pathogens such as Klebsiella pneumoniae, Streptococcus suis and Streptococcus porcinus were linked to cutting boards associated with pork; Campylobacter fetus, Staphylococcus aureus, Escherichia coli, and A. caviae in those associated with poultry; and Streptococcus varanii, A. caviae, Vibrio fluvialis, and Vibrio parahaemolyticus in those associated with seafood. Identifying non-foodborne clinically relevant pathogens in wet market cutting boards in this study confirms the need for safety approaches for wet market meat, including cold storage. The presented study justifies the need for future systematic epidemiological studies to determine identified microbial pathogens. Such studies should bring about significant improvements in the management of hygienic practices in Hong Kong's wet markets and work towards a One Health goal by recognizing the importance of wet markets as areas interconnecting food processing with animal and clinical environments.

10.
J Control Release ; 329: 731-742, 2021 01 10.
Article in English | MEDLINE | ID: mdl-33031879

ABSTRACT

Dictamnine is an active pharmaceutical ingredient in Dictamnus dasycarpus, a Chinese herbal medicine widely used for the treatment of skin inflammations such as atopic dermatitis (AD). Oxazolone has been demonstrated to induce significant skin inflammation and produce inflammatory cytokine expression identical to that of AD. An in vitro HaCaT inflammation model treated with dictamnine, which efficiently scavenged the reactive oxygen species (ROS) and mitochondrial ROS (mROS), and it reduced interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α) expression, NLRP3 inflammasome activation, and NF-κB expression. To explore the anti-inflammatory mechanism of dictamnine and enhance sustained drug release and penetration into epidermal structures in a dermatitis mouse model, we prepared PLGA-nanocarrier-encapsulated dictamnine (Dic-PLGA-NC) in a specifically designed bioreactor, namely an ultrasound composite streams-impinging mixer (U-SiM). Mouse dermatitis model was treated with Dic-PLGA-NC medication, spleens were collected to evaluate body weight ratio, and skin was retrieved for histological examination and two-photon microscopy. The data demonstrate that Dic-PLGA-NC efficiently penetrated the dermal layer, making it superior to naked dictamnine; moreover, it ameliorated the dermatitis symptoms and inflammatory cytokine expression in vivo. Dic-PLGA-NC produced using the U-SiM bioreactor could be used in new manufacturing processes for drugs to treat AD.


Subject(s)
Dermatitis, Atopic , Quinolines , Animals , Cytokines , Dermatitis, Atopic/drug therapy , Disease Models, Animal , Inflammation , Mice , NF-kappa B , Oxazolone , Skin , Tumor Necrosis Factor-alpha
11.
Microorganisms ; 8(12)2020 Dec 07.
Article in English | MEDLINE | ID: mdl-33297499

ABSTRACT

Accessing food through wet markets is a common global daily occurrence, where fresh meat can be purchased to support an urbanizing world population. Similar to the wet markets in many other metropolitan cities in Asia, Hong Kong wet markets vary and are characterized by differing hygiene routines and access to essential modern technologies. The lack of risk assessments of food contact surfaces in these markets has led to substantial gaps in food safety knowledge and information that could help improve and maintain public health. Microbial profiling analyses were conducted on cutting boards that had been used to process pork, poultry, and seafood at 11 different wet markets. The markets differed in hygiene protocols and access to modern facilities. Irrespective of whether wet markets have access of modern infrastructure, the hygiene practices were largely found to be inefficient based on the prevalence of bacterial species typically associated with foodborne pathogens such as Campylobacter fetus, Clostridium perfringens, Staphylococcus aureus, and Vibrio parahaemolyticus; indicator organisms such as Escherichia coli; as well as nonfoodborne pathogenic bacterial species potentially associated with nosocomial infections, such as Klebsiella pneumoniae and Enterobacter cloacae. Other Vibrio species, V. parahaemolyticus and V. vulnificus, typically associated with contaminated raw or undercooked seafood with the potential to cause illness in humans, were also found on wooden cutting boards. This study indicated that the hygienic practices used in Hong Kong wet markets are not sufficient for preventing the establishment of spoilage or pathogenic organisms. This study serves as a basis to review current hygiene practices in wet markets and provides a framework to reassess existing safety protocols.

12.
J Adolesc ; 83: 62-71, 2020 08.
Article in English | MEDLINE | ID: mdl-32745793

ABSTRACT

INTRODUCTION: The present study calls attention to the longitudinal relations between mothers', fathers', and adolescents' emotion dysregulation and adolescents' internalizing problems. To this end, we tested the associations between family members' emotion dysregulation and adolescents' internalizing problems over time. METHODS: Over a 12-month period, 386 Chinese families from Hong Kong involving mothers, fathers, and adolescent children (children at 12-17 years of age; boys = 185, girls = 201) completed a set of questionnaires twice. RESULTS: Multi-group path analysis revealed unidirectional effects of mothers' emotion dysregulation on fathers' and adolescents' emotion dysregulation over time. Adolescents' emotion dysregulation was also related to their subsequent internalizing problems. The associations did not differ as a function of adolescents' gender. CONCLUSION: The present findings underscore the significance of mothers' emotion dysregulation on fathers' and adolescents' emotion dysregulation. As a risk factor, adolescents' emotion dysregulation was also predictive of their internalizing problems 12 months later. Taken together, this study serves to inform prevention and intervention efforts in promoting emotion regulation as a family asset associated with fewer adolescents' internalizing problems.


Subject(s)
Adolescent Behavior/psychology , Defense Mechanisms , Emotional Regulation , Family Relations/psychology , Adolescent , Adult , Child , Fathers/psychology , Female , Hong Kong , Humans , Longitudinal Studies , Male , Mothers/psychology , Surveys and Questionnaires
13.
Nanomaterials (Basel) ; 9(1)2019 Jan 05.
Article in English | MEDLINE | ID: mdl-30621291

ABSTRACT

The specific delivery of messenger RNA (mRNA) is an excellent alternative to plasmid DNA, due to the latter's potential risk for random integration into the host genome. In this study, we propose the use of specially tailored polyplex nanomicelles for the intravenous delivery of mRNA into the brain of mice. In brief, along the backbone of a polyaspartamide polymer that is terminated with a 42k Polyethylene glycol chain (PEG), aminoethylene-repeating groups (two, three, and four units, respectively) were conjugated to side-chains to promote electrostatic interactions with mRNA. This structural configuration would ultimately condense into a polyplex nanomicelle ranging between 24 and 34 nm, as was confirmed by transmission electron microscopy (TEM) and dynamic light scattering (DLS) while the chemistry of the synthesis was validated through NMR analysis. Subsequently, we hypothesized an important correlation pertaining to the role of hydrogen bonding between the interaction of polyamine and mRNA in due course. As a proof of concept, we encapsulated the luciferase (Luc2) mRNA as a reporter gene through in vitro transcription (IVT) and subsequently infused the polyplex nanomicelles into mouse brains via an intracerebroventricular (ICV) injection to bypass the blood⁻brain barriers (BBB). Data revealed that PEGylated polyplex nanomicelles possessing four repeating units of aminoethylene groups had exhibited the best Luc2 mRNA delivery efficiency with no significant immune response registered.

14.
Genesis ; 56(11-12): e23261, 2018 12.
Article in English | MEDLINE | ID: mdl-30375740

ABSTRACT

MAB21L2(R51C) is one of the five documented MAB21L2 mutations in human patients with bilateral eye malformations identified via whole exome sequencing. In addition to the eye abnormality, patients with MAB21L2 R51C/+ mutation also have skeletal dysplasia and intellectual disability. To evaluate the pathology of this mutant allele systematically in understanding the functional role of MAB21L2 in human development, we introduce the R51C mutation into the mouse genome by CRISPR/Cas9 system to generate a mouse model for detailed characterization. The Mab21l2 R51C/+ mice have eyeless phenotype and skeletal abnormalities. Micro-computed tomography (micro-CT) analysis showed the Mab21l2 R51C/+ mice have no eye balls but with two abnormal tissues underneath the brain. Histological analysis revealed that the early eye development in the mutant embryos is interrupted. In addition, Mab21l2 R51C/+ mice also have joint fusion phenotype; the humerus is fused with radius, whereas femur is fused with tibia. Limbs in the mutant animals are distinctly shorter than the wild type; and deltoid tuberosities in humeri are absent in these Mab21l2 R51C/+ mice. In summary, we showed that our Mab21l2 R51C/+ mutant mice have recapitulated the pathological features in eye and bone of human patients. Further analyses of the mutant phenotype with molecular markers will provide insight on how MAB21L2 guides the optic differentiation and skeletogenesis, revealing specific underlying pathogenic mechanism of the MAB21L2(R51C) mutation.


Subject(s)
Eye Abnormalities/genetics , Eye Proteins/genetics , Intracellular Signaling Peptides and Proteins/genetics , Musculoskeletal Abnormalities/genetics , Phenotype , Animals , Disease Models, Animal , Mice , Mutation, Missense , Syndrome
15.
Sci Rep ; 1: 20, 2011.
Article in English | MEDLINE | ID: mdl-22355539

ABSTRACT

Recent studies showed that IL-22 plays a protective role in the host defense. However, the contribution of polymorphisms of the IL-22 gene to human TB susceptibility remains untested. We have designed a computational approach to select functional SNPs in the IL-22 gene and genotyped them in a two-stage case-control study in Chinese (479 cases and 358 controls). We found that rs2227473, an SNP in the promoter region of IL-22, is associated with TB susceptibility at both stages of our study. The SNP shows associations with p-values of 0.028 and 0.034 respectively, and a combined p-value of 0.0086, with odds ratio at 0.65 (95% confidence interval 0.45-0.90). We further validated the association with an independent cohort (413 cases and 241 controls in Chinese). Our functional studies showed that patients with A allele have significantly higher IL-22 expression than those without A allele under both non-specific and specific stimulations.


Subject(s)
Genetic Predisposition to Disease/epidemiology , Genetic Predisposition to Disease/genetics , Interleukins/genetics , Polymorphism, Single Nucleotide/genetics , Selection, Genetic/genetics , Tuberculosis/epidemiology , Tuberculosis/genetics , Adolescent , Adult , Aged , Aged, 80 and over , China/epidemiology , Female , Humans , Male , Middle Aged , Prevalence , Risk Assessment , Young Adult , Interleukin-22
16.
Science ; 325(5948): 1665-7, 2009 Sep 25.
Article in English | MEDLINE | ID: mdl-19679770

ABSTRACT

Sensing from the ultraviolet-visible to the infrared is critical for a variety of industrial and scientific applications. Today, gallium nitride-, silicon-, and indium gallium arsenide--based detectors are used for different sub-bands within the ultraviolet to near-infrared wavelength range. We demonstrate polymer photodetectors with broad spectral response (300 to 1450 nanometers) fabricated by using a small-band-gap semiconducting polymer blended with a fullerene derivative. Operating at room temperature, the polymer photodetectors exhibit detectivities greater than 10(12) cm Hz(1/2)/W and a linear dynamic range over 100 decibels. The self-assembled nanomorphology and device architecture result in high photodetectivity over this wide spectral range and reduce the dark current (and noise) to values well below dark currents obtained in narrow-band photodetectors made with inorganic semiconductors.

17.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-814203

ABSTRACT

OBJECTIVE@#To determine the expression of DLK1 gene in acute leukemias (AL) and its function in erythroid differentiation of K562 cells.@*METHODS@#We detected the expression of DLK1 gene in 65 different acute leukemia categories (a test group) and 34 normal bone marrow controls (a control group) with RT-PCR. DLK1 protein in 20 out of the 65 AL patients and 13 of the 34 controls was assayed by Western blot. The K562 cell line was induced to erythroid differentiation by hemin. We observed the relationship between its expression and erythroid differentiation.@*RESULTS@#Both leukemia cells and normal marrow cells expressed DLK1. The expression of DLK1 mRNA in patients in the test group was higher than that in the control group (P=0.018), while there was no significance between acute lymphoblastic leukemia and acute myelogenous leukemia (P>0.05).The expression of DLK1 mRNA in the test group at onset had no relation with the WBC and platelet count in the total peripheral blood, and the same was true for blast cell rates in bone marrow cells.The level of DLK1 protein in the test group was higher than that in the control group, which was consistent with the mRNA expression (P=0.042). The expression of DLK1 mRNA decreased gradually with K562 cells towards hemin-induced erythroid differentiation.@*CONCLUSION@#DLK1 gene may be involved in leukemia,but the mRNA level of DLK1 has no relation with some clinical characteristics of AL patients at onset. DLK1 may inhibit the erythroid differentiation of K562 cells.


Subject(s)
Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Young Adult , Acute Disease , Calcium-Binding Proteins , Case-Control Studies , Cell Differentiation , Genetics , Cell Transformation, Neoplastic , Genetics , Erythroid Cells , Pathology , Erythroid Precursor Cells , Pathology , Intercellular Signaling Peptides and Proteins , Genetics , Metabolism , K562 Cells , Leukemia , Genetics , Metabolism , Membrane Proteins , Genetics , Metabolism , RNA, Messenger , Genetics , Metabolism
18.
Blood Purif ; 22(4): 351-9, 2004.
Article in English | MEDLINE | ID: mdl-15297785

ABSTRACT

BACKGROUND/AIMS: Left ventricular hypertrophy (LVH) has long been known as an independent risk factor for cardiovascular deaths, in both dialysis and general populations. Numerous factors influence the pathophysiology of LVH. However, extracellular fluid may have a particularly important influence on this impact. Inferior vena cava diameter (IVCD) estimation is a non-invasive and relatively convenient method for obtaining a good correlation with the intravascular fluid status, and may obtain an optimal dry weight (DW) for chronic hemodialysis patients. This study estimates the DW of end-stage renal disease (ESRD) patients by echocardiographic measurement of the IVCD to observe changes in cardiac morphology and function. METHODS: A total of 88 patients, ranging from 26 to 90 (59.4 +/- 13.3) years of age, were involved in this study. The patients were divided into study (n = 48) and control (n = 40) groups. All patients received IVCD assessment via echocardiography bi-monthly for 1 year. In the study group patients, DW was adjusted according to the IVCD by echocardiography. Meanwhile, in the control group patients, DW was adjusted based on traditional clinical parameters. All patients underwent cardiac examinations and measurements, including left ventricular mass (LVM), wall thickness, chamber size and left ventricular systolic function by echocardiography, at the beginning and end of the study. RESULTS: Both groups displayed comparable clinical and biochemical parameters. The IVCD index correlated well with the cardiac parameters estimated by echocardiography. The LVM and left ventricular mass index (LVMI) was reduced significantly in the study group patients (from 200 +/- 64.2 to 187 +/- 63.2 g, p = 0.021; from 132 +/- 37.6 to 123 +/- 37.3 g/m(2), p = 0.014, respectively). Furthermore, the study group patients with fluid overload, named study subgroup A, displayed significant differences not only in LVM and LVMI, but also in septal wall thickness, left ventricular end-diastolic dimension and left atrial dimension. In contrast, the control group displayed no changes in these cardiac architectures during the study period. CONCLUSION: Adjusting DW via the IVCD measured by echocardiography for hemodialysis patients may prevent the progression of chamber dilatation and LVH, especially for patients with fluid overload.


Subject(s)
Echocardiography , Hypertrophy, Left Ventricular/diagnostic imaging , Kidney Failure, Chronic/therapy , Renal Dialysis , Vena Cava, Inferior/diagnostic imaging , Adult , Aged , Aged, 80 and over , Atrial Function , Female , Heart Atria , Humans , Male , Middle Aged , Radiography , Systole , Vena Cava, Inferior/abnormalities , Ventricular Function, Left
19.
J Am Chem Soc ; 124(14): 3508-9, 2002 Apr 10.
Article in English | MEDLINE | ID: mdl-11929231

ABSTRACT

The synthesis, characterization and biological application of mannose encapsulated gold nanoparticles (m-AuNP) are reported. m-AuNP is well dispersed and very stable without aggregation in the media of broad ion strength and pH ranges. The selective binding of m-AuNP to the mannose adhesin FimH of bacterial type 1 pili is demonstrated using transmission electron microscopy. The competition assay with free mannose suggests that m-AuNP binds FimH better than free mannose does. This work demonstrates that carbohydrate attached nanoparticles can be used as an efficient affinity label and a multi-ligand carrier in a biological system.


Subject(s)
Adhesins, Bacterial/chemistry , Adhesins, Escherichia coli , Escherichia coli/metabolism , Fimbriae Proteins , Fimbriae, Bacterial/chemistry , Gold/chemistry , Mannose/chemistry , Adhesins, Bacterial/metabolism , Escherichia coli/chemistry , Fimbriae, Bacterial/metabolism , Gold/metabolism , Mannose/metabolism , Particle Size
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