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1.
J Virus Erad ; 6(1): 11-18, 2020 Feb 20.
Article in English | MEDLINE | ID: mdl-32175086

ABSTRACT

OBJECTIVES: Integration of HIV and non-communicable disease services improves the quality and efficiency of care in low- and middle-income countries (LMICs). We aimed to describe current practices for the screening and management of atherosclerotic cardiovascular disease (ASCVD) among adult HIV clinics in Asia. METHODS: Sixteen LMIC sites included in the International Epidemiology Databases to Evaluate AIDS - Asia-Pacific network were surveyed. RESULTS: Sites were mostly (81%) based in urban public referral hospitals. Half had protocols to assess tobacco and alcohol use. Protocols for assessing physical inactivity and obesity were in place at 31% and 38% of sites, respectively. Most sites provided educational material on ASCVD risk factors (between 56% and 75% depending on risk factors). A total of 94% reported performing routine screening for hypertension, 100% for hyperlipidaemia and 88% for diabetes. Routine ASCVD risk assessment was reported by 94% of sites. Protocols for the management of hypertension, hyperlipidaemia, diabetes, high ASCVD risk and chronic ischaemic stroke were in place at 50%, 69%, 56%, 19% and 38% of sites, respectively. Blood pressure monitoring was free for patients at 69% of sites; however, most required patients to pay some or all the costs for other ASCVD-related procedures. Medications available in the clinic or within the same facility included angiotensin-converting enzyme inhibitors (81%), statins (94%) and sulphonylureas (94%). CONCLUSION: The consistent availability of clinical screening, diagnostic testing and procedures and the availability of ASCVD medications in the Asian LMIC clinics surveyed are strengths that should be leveraged to improve the implementation of cardiovascular care protocols.

2.
Regul Toxicol Pharmacol ; 94: 172-182, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29408293

ABSTRACT

This paper provides compound-specific toxicology limits for 20 widely used synthetic reagents and common by-products that are potential impurities in drug substances. In addition, a 15 µg/day class-specific limit was developed for monofunctional alkyl bromides, aligning this with the class-specific limit previously defined for monofunctional alkyl chlorides. Both the compound- and class-specific toxicology limits assume a lifetime chronic exposure for the general population (including sensitive subpopulations) by all routes of exposure for pharmaceuticals. Inhalation-specific toxicology limits were also derived for acrolein, formaldehyde, and methyl bromide because of their localized toxicity via that route. Mode of action was an important consideration for a compound-specific toxicology limit. Acceptable intake (AI) calculations for certain mutagenic carcinogens assumed a linear dose-response for tumor induction, and permissible daily exposure (PDE) determination assumed a non-linear dose-response. Several compounds evaluated have been previously incorrectly assumed to be mutagenic, or to be mutagenic carcinogens, but the evidence reported here for such compounds indicates a lack of mutagenicity, and a non-mutagenic mode of action for tumor induction. For non-mutagens with insufficient data to develop a toxicology limit, the ICH Q3A qualification thresholds are recommended. The compound- and class-specific toxicology limits described here may be adjusted for an individual drug substance based on treatment duration, dosing schedule, severity of the disease and therapeutic indication.


Subject(s)
Bromides/standards , Carcinogens/standards , Drug Contamination , Indicators and Reagents/standards , Mutagens/standards , Animals , Bromides/classification , Bromides/toxicity , Carcinogens/toxicity , Drug Industry , Humans , Indicators and Reagents/toxicity , Mutagens/toxicity , Risk Assessment
3.
Chem Commun (Camb) ; 53(53): 7234-7237, 2017 Jun 29.
Article in English | MEDLINE | ID: mdl-28352901

ABSTRACT

Chemical genetics has arisen as a powerful approach for identifying novel anti-cancer agents. However, a major bottleneck of this approach is identifying the targets of lead compounds that arise from screens. Here, we coupled the synthesis and screening of fragment-based cysteine-reactive covalent ligands with activity-based protein profiling (ABPP) chemoproteomic approaches to identify compounds that impair colorectal cancer pathogenicity and map the druggable hotspots targeted by these hits. Through this coupled approach, we discovered a cysteine-reactive acrylamide DKM 3-30 that significantly impaired colorectal cancer cell pathogenicity through targeting C1101 on reticulon 4 (RTN4). While little is known about the role of RTN4 in colorectal cancer, this protein has been established as a critical mediator of endoplasmic reticulum tubular network formation. We show here that covalent modification of C1101 on RTN4 by DKM 3-30 or genetic knockdown of RTN4 impairs endoplasmic reticulum and nuclear envelope morphology as well as colorectal cancer pathogenicity. We thus put forth RTN4 as a potential novel colorectal cancer therapeutic target and reveal a unique druggable hotspot within RTN4 that can be targeted by covalent ligands to impair colorectal cancer pathogenicity. Our results underscore the utility of coupling the screening of fragment-based covalent ligands with isoTOP-ABPP platforms for mining the proteome for novel druggable nodes that can be targeted for cancer therapy.


Subject(s)
Acrylamide/pharmacology , Antineoplastic Agents/pharmacology , Colorectal Neoplasms/drug therapy , Cysteine/chemistry , Endoplasmic Reticulum/drug effects , Nogo Proteins/antagonists & inhibitors , Proteomics , Acrylamide/chemistry , Antineoplastic Agents/chemistry , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , Endoplasmic Reticulum/metabolism , Humans , Ligands , Nogo Proteins/genetics , Nogo Proteins/metabolism , Nuclear Envelope/drug effects , Nuclear Envelope/metabolism
4.
Oncogene ; 35(43): 5674-5685, 2016 10 27.
Article in English | MEDLINE | ID: mdl-27065329

ABSTRACT

HLJ1 (DNAJB4), a DNAJ/Hsp40 chaperone, has emerged as a novel prognostic marker in lung cancers; however, the molecular contribution and functionality in neoplastic diseases remain to be established. This study demonstrated that HLJ1 inhibits epithelial-mesenchymal transition in vitro and reduces lung cancer metastasis in vivo. Using shRNA silencing and ectopic expression of HLJ1, we found that HLJ1 not only suppresses catalytic activity of Src but also downregulates the formation of oncogenic complexes associated with the EGFR, FAK and STAT3 signaling pathways. A screen of specimens from HLJ1-knockout mice and lung cancer patients validated that HLJ1 expression is inversely correlated with Src activity. Mechanistically, HLJ1 protein directly bound to catalytic and protein-binding domains of Src through its amino acid Y172 and the P301/P304 motif. Following Src-induced HLJ1 phosphorylation at Y172, HLJ1-Src interaction was elevated, resulting in Src inhibition and malignancy suppression. Interestingly, both Src-binding regions also occurred in other DNAJB family members and contributed to anti-invasive activities of DNAJB proteins. We conclude that HLJ1 is an endogenous Src inhibitor that can suppress cancer metastasis through complex interacting mechanisms. This HLJ1-Src complex might provide a promising molecular model for developing new anticancer strategies.


Subject(s)
HSP40 Heat-Shock Proteins/metabolism , Neoplasms/metabolism , Neoplasms/pathology , src-Family Kinases/antagonists & inhibitors , Amino Acid Sequence , Animals , Disease Models, Animal , Disease Progression , Enzyme Activation , Gene Expression , Gene Expression Regulation, Neoplastic , Gene Knockdown Techniques , HSP40 Heat-Shock Proteins/chemistry , HSP40 Heat-Shock Proteins/genetics , HSP40 Heat-Shock Proteins/pharmacology , Humans , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Male , Mice , Mice, Knockout , Models, Biological , Models, Molecular , Mutation , Neoplasm Invasiveness , Neoplasm Metastasis , Neoplasms/genetics , Protein Binding , Protein Conformation , Protein Interaction Domains and Motifs , RNA Interference , RNA, Small Interfering/genetics , src Homology Domains , src-Family Kinases/chemistry , src-Family Kinases/metabolism
5.
J Nanosci Nanotechnol ; 15(5): 3728-32, 2015 May.
Article in English | MEDLINE | ID: mdl-26504998

ABSTRACT

High-T(c) Josephson junctions were fabricated by nanolithography using focused ion beam (FIB) milling and ion implantation. The junctions were formed in a YBa2Cu3O7-x, thin film in regions defined using a gold-film mask with 50-nm-wide (top) slits, engraved by FIB. The focused ion beam system parameters for dwell time and passes were set to remove gold up to a precise depth. 150 keV oxygen ions were implanted at a nominal dose of up to 5 x 10(13) ions/cm2 into YBa2Cu3O7-x microbridges through the nanoscale slits. The current-voltage curves of the ion implantation junctions exhibit resistive-shunted-junction-like behavior at 77 K. The junction had an approximately linear temperature dependence of critical current. Shapiro steps were observed under microwave irradiation. A 50-nm-wide slit and 0-20-nm-thick buffer layers were chosen in order to make Josephson junctions due to the V-shape of the FIB-milled trench.


Subject(s)
Ions/chemistry , Nanostructures/chemistry , Nanotechnology/methods , Electrochemistry , Gold/chemistry , Metals/chemistry , Microscopy, Electron, Scanning , Oxygen/chemistry
6.
Phys Rev Lett ; 114(21): 217002, 2015 May 29.
Article in English | MEDLINE | ID: mdl-26066452

ABSTRACT

We apply a recently developed method combining first principles based Wannier functions with solutions to the Bogoliubov-de Gennes equations to the problem of interpreting STM data in cuprate superconductors. We show that the observed images of Zn on the surface of Bi_{2}Sr_{2}CaCu_{2}O_{8} can only be understood by accounting for the tails of the Cu Wannier functions, which include significant weight on apical O sites in neighboring unit cells. This calculation thus puts earlier crude "filter" theories on a microscopic foundation and solves a long-standing puzzle. We then study quasiparticle interference phenomena induced by out-of-plane weak potential scatterers, and show how patterns long observed in cuprates can be understood in terms of the interference of Wannier functions above the surface. Our results show excellent agreement with experiment and enable a better understanding of novel phenomena in the cuprates via STM imaging.

7.
Phys Rev Lett ; 108(12): 127203, 2012 Mar 23.
Article in English | MEDLINE | ID: mdl-22540620

ABSTRACT

Combining thermodynamic measurements with theoretical calculations we demonstrate that the iridates A2IrO3 (A=Na, Li) are magnetically ordered Mott insulators where the magnetism of the effective spin-orbital S=1/2 moments can be captured by a Heisenberg-Kitaev (HK) model with interactions beyond nearest-neighbor exchange. Experimentally, we observe an increase of the Curie-Weiss temperature from θ≈-125 K for Na2IrO3 to θ≈-33 K for Li2IrO3, while the ordering temperature remains roughly the same T(N)≈15 K. Using functional renormalization group calculations we show that this evolution of θ and T(N) as well as the low temperature zigzag magnetic order can be captured within this extended HK model. We estimate that Na2IrO3 is deep in a magnetically ordered regime, while Li2IrO3 appears to be close to a spin-liquid regime.

8.
Phys Rev Lett ; 105(2): 026402, 2010 Jul 09.
Article in English | MEDLINE | ID: mdl-20867721

ABSTRACT

An excitation at 201 meV is observed in the doped-hole ladder cuprate Sr14Cu24O41, using ultraviolet resonance Raman scattering with incident light at 3.7 eV polarized along the rungs. The excitation is of charge nature, with a temperature independent excitation energy, and can be understood via an intraladder pair-breaking process. The intensity tracks closely the order parameter of the charge density wave in the ladder CDW(L), but persists above its transition temperature T(CDW(L)), indicating a strong local pairing above the T(CDW(L)). The 201 meV excitation vanishes in La6Ca8Cu24O(41+δ), and La5Ca9Cu24O41 which are samples with no holes in the ladders. Our results suggest that the doped holes in the ladder are composite bosons consisting of paired holons that order below T(CDW).

9.
Phys Rev Lett ; 105(20): 207201, 2010 Nov 12.
Article in English | MEDLINE | ID: mdl-21231259

ABSTRACT

We report direct evidence of room-temperature ferromagnetic ordering in O-deficient ZnO:Cu films by using soft x-ray magnetic circular dichroism and x-ray absorption. Our measurements have revealed unambiguously two distinct features of Cu atoms associated with (i) magnetically ordered Cu ions present only in the oxygen-deficient samples and (ii) magnetically disordered regular Cu2+ ions present in all the samples. We find that a sufficient amount of both oxygen vacancies (V(O)) and Cu impurities is essential to the observed ferromagnetism, and a non-negligible portion of Cu impurities is uninvolved in the magnetic order. Based on first-principles calculations, we propose a microscopic "indirect double-exchange" model, in which alignments of localized large moments of Cu in the vicinity of the V(O) are mediated by the large-sized vacancy orbitals.

10.
Phys Rev Lett ; 99(3): 037602, 2007 Jul 20.
Article in English | MEDLINE | ID: mdl-17678327

ABSTRACT

Significant nanoscale disorder of Cu and Ca atomic substitution is observed in CaCu(3)Ti(4)O(12), based on our integrated study using quantitative electron diffraction and extended x-ray absorption fine structure. Unambiguous identification of this previously omitted disorder is made possible by the unique sensitivity of these probes to valence-electron distribution and short-range order. Furthermore, first-principles-based theoretical analysis indicates that the Ca-site Cu atoms possess partially filled degenerate e(g) states, suggesting significant boost of dielectric response from additional low-energy electronic contributions. Our study points to a new route of enhancing dielectric response in transitional metal oxides by exploiting the strong electronic correlation beyond classical static pictures.

11.
Mutat Res ; 633(2): 80-94, 2007 Oct 04.
Article in English | MEDLINE | ID: mdl-17644026

ABSTRACT

Drug synthesis and/or formulation can generate genotoxic impurities. For instance, strong acid/alcohol interactions during the process of drug salt formation produce alkylating agents such as alkyl halides and alkyl esters of alkyl sulfonic acids. The genotoxicity of a few classic alkylating agents such as methyl and ethyl methanesulfonate have been previously well characterized, whereas the majority of compounds from this class have only been tested in the Salmonella reversion assay. Therefore, the goal of this study was to investigate clastogenicity and DEL recombination profiles of 22 halogenated alkanes and alkylesters of sulfuric and alkane-, aryl-sulfonic acids using a battery of cellular and molecular assays. The in-vitro micronucleus assay in CHO cells was used to measure clastogenicity and the deletion recombination (DEL) assay in S. cerevisiae provided a measure of DNA deletions. We also examined the compounds' reactivity towards 4-(p-nitrobenzyl)pyridine (NBP), a surrogate molecule for biological ring nitrogens. Methylating agents were most potent in all three assays and the alkyl chlorides evaluated in our study were negative in all three assays. Also, a strong correlation was found between the MN, DEL and NBP assays. In summary, this study contributes to a better understanding of the genotoxic properties of common alkyl halides and alkyl esters with alkylating activity and might provide guidance for managing risk of genotoxic process-related impurities of drug substances and products.


Subject(s)
Alkylating Agents/toxicity , DNA Damage , Mutagens/toxicity , Alkylation , Animals , CHO Cells , Cricetinae , Cricetulus , Esters , Gene Deletion , Micronucleus Tests , Mutagenicity Tests , Saccharomyces cerevisiae/genetics , Sulfonic Acids/toxicity , Sulfuric Acid Esters/toxicity
12.
Phys Rev Lett ; 97(17): 176402, 2006 Oct 27.
Article in English | MEDLINE | ID: mdl-17155487

ABSTRACT

A sharp feature in the charge-density excitation spectra of single-crystal MgB2, displaying a remarkable cosinelike, periodic energy dispersion with momentum transfer (q) along the c* axis, has been observed for the first time by high-resolution nonresonant inelastic x-ray scattering (NIXS). Time-dependent density-functional theory calculations show that the physics underlying the NIXS data is strong coupling between single-particle and collective degrees of freedom, mediated by large crystal local-field effects. As a result, the small-q collective mode residing in the single-particle excitation gap of the B pi bands reappears periodically in higher Brillouin zones. The NIXS data thus embody a novel signature of the layered electronic structure of MgB2.

13.
Phys Rev Lett ; 94(4): 047203, 2005 Feb 04.
Article in English | MEDLINE | ID: mdl-15783591

ABSTRACT

We report a study of electronic excitations in manganites exhibiting a range of ground states, using resonant inelastic x-ray scattering (RIXS) at the Mn K edge. Excitations with temperature dependent changes correlated with the magnetism were observed as high as 10 eV. By calculating Wannier functions, and finite-q response functions, we associate this dependence with intersite d-d excitations. The calculated dynamical structure factor is found to be similar to the RIXS spectra.

14.
J Occup Rehabil ; 12(2): 77-91, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12014228

ABSTRACT

The 1-year prevalence of neck pain and possible risk factors among university academic staff were investigated. Self-administered questionnaires were distributed to all the full-time academic staff in one of the universities in Hong Kong. The 1-year prevalence of neck pain was investigated. The relationship between individual factors, job nature, psychosocial factors, and neck pain were also analyzed. The 1-year prevalence of neck pain among after being an academic staff was 46.7%. A significant association was found between gender and neck pain (p = 0.02). The percentage of female academic staff with neck pain (62%) was higher than that in male staff (38%). This matched the results of other studies, which demonstrated that neck pain was more prevalent in women. There was a significant association between head posture during computer processing and neck pain (p = 0.02). Among those with neck pain during computer processing, 60.5% had a forward head posture. However, a low correlation between psychosocial factors and neck pain was demonstrated (r = 0.343). Academic staff in tertiary institutions could be considered as a high-risk group of job-related neck pain.


Subject(s)
Faculty , Neck Pain/prevention & control , Adult , Female , Hong Kong/epidemiology , Humans , Male , Middle Aged , Neck Pain/epidemiology , Neck Pain/psychology , Posture , Prevalence , Risk Factors , Sex Distribution , Social Environment , Task Performance and Analysis
15.
Mycologia ; 94(5): 866-72, 2002.
Article in English | MEDLINE | ID: mdl-21156561

ABSTRACT

A synnematous species of Penicillium, P. calidicanium, is described and illustrated. The fungus was isolated from soil in Taiwan. Penicillium calidicanium can be placed in subgenus Biverticillium because of its symmetrical, biverticillate penicilli, ampulliform to acerose phialides, and ability to produce abundant synnemata in Czapek yeast extract agar, malt extract agar, and Czapek's solution agar. It is close to P. duclauxii and P. vulpinum, but differs in colony morphology, growth rate, morphology of the synnemata, and ornamentation of the conidial wall.

16.
Chang Gung Med J ; 24(6): 399-403, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11512373

ABSTRACT

Spontaneous subconjunctival orbital fat prolapse is an uncommon but benign entity. It is seldom discussed in the literature, and is sometimes confused with other ocular surface tumors, such as dermolipoma. We present 3 cases, two of which are bilateral, the other being unilateral. Two cases underwent surgical excision due to ocular irritation, and the pathology proved mature adipose tissue compatible with the diagnosis. Computed tomography (CT) was available for 1 case and revealed a fat-compatible radiolucent mass continuous with the intraconal fat. Some other reports have presumed that the intraconal fat was prolapsed from a dehiscence of Tenon's capsule. However, according to our surgical findings, we suggest that the possible weak point for intraconal orbital fat prolapse is between the regions where the rectus muscle tendons penetrate into Tenon's capsule. The fat just bulges anteriorly, but not penetrates the Tenon's capsule and the intermuscular septum.


Subject(s)
Conjunctival Diseases/diagnosis , Fats , Orbital Diseases/diagnosis , Aged , Conjunctival Diseases/etiology , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Orbital Diseases/etiology , Prolapse
17.
Eur J Hum Genet ; 9(8): 638-41, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11528511

ABSTRACT

Myotonic dystrophy type 1 (DM1) is an autosomal dominant neuromuscular disorder caused by a CTG trinucleotide expansion at the DM1 locus. In this study, we investigated the frequency distribution of various CTG repeats in normal alleles and haplotyped the normal and expanded DM1 locus in a group of Taiwanese people. In the 496 normal chromosomes examined, up to 18 alleles with different CTG lengths from 5 to 30 repeats were found and the frequency of (CTG)(>18) alleles was only 1.4% (7/496), predicting a low prevalence of DM1. In addition, there is no absolute association between (CTG)(5-19) alleles and Alu insertion/deletion polymorphism observed on normal chromosomes. All DM1 alleles examined, however, were found to be associated with the Alu insertion. Further detailed genetic analysis demonstrated that at least eight haplotypes, including a new haplotype (L), were present in the Taiwanese population and that all DM1 alleles were with the same haplotype (haplotype A) as that identified in Canadian and Japanese DM1 populations. These findings support the notion that the out-of-Africa DM1 alleles were originated by stepwise expansion from a pool of large-sized normal chromosomes with haplotype A.


Subject(s)
Founder Effect , Haplotypes/genetics , Mutation/genetics , Myotonic Dystrophy/epidemiology , Myotonic Dystrophy/genetics , Alleles , Cytosine Nucleotides/genetics , Gene Frequency/genetics , Guanine Nucleotides/genetics , Humans , Taiwan/epidemiology , Thymine Nucleotides/genetics , Trinucleotide Repeat Expansion/genetics
18.
Ophthalmic Surg Lasers ; 32(1): 73-6, 2001.
Article in English | MEDLINE | ID: mdl-11195748

ABSTRACT

A case is reported of a traumatic macular hole caused by a high-energy Nd:YAG laser. The initial ocular examination revealed an explosive, crater-shaped, full-thickness macular hole surrounded by local edema and detachment. By the 12th day after the injury, the hole had shrunk progressively and was covered by a thin fibrin-like membrane. A thick epiretinal membrane covered the injured area 1 month after the injury. Nine months after the injury, the macular hole closed spontaneously with a partially detached epiretinal membrane. This case demonstrates one of the natural healing processes of a traumatic macular hole. Although the hole finally closed, the patient did not regain his vision because of the severe damage to the photoreceptors, retinal pigment epithelium, and choroid.


Subject(s)
Eye Injuries/etiology , Lasers/adverse effects , Retina/injuries , Retinal Perforations/etiology , Adult , Epiretinal Membrane/etiology , Eye Injuries/pathology , Humans , Male , Retina/pathology , Retinal Detachment/etiology , Retinal Perforations/pathology , Visual Acuity , Wound Healing
19.
Ann Diagn Pathol ; 4(5): 329-36, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11073340

ABSTRACT

The conventional positive control in immunohistochemistry consists of a separately immunostained slide containing tissue known to show positive reaction with the antibody. Although it can indicate that the reagents are sound, it cannot guarantee that the appropriate reagents have indeed been dispensed in the correct order on the test cases. Furthermore, positive controls are costly because they often account for 20% to 40% of all immunostained slides in a diagnostic surgical pathology laboratory. We describe a simple method to produce a multitissue spring-roll control block, comprising mostly normal tissues. The multitissue controls are mounted on the same slides of the test cases, and thus undergo the identical immunostaining procedures as the test tissues. Therefore they can provide the best assurance that the immunostains are working properly on the individual slides, the expected sensitivity is achieved, and the specificity is as expected. The wisdom of the conventional negative control is also questioned. When two or more immunostains are performed on a case, they should be sufficient to indicate the presence or absence of nonspecific staining.


Subject(s)
Immunohistochemistry/methods , Pathology, Surgical/methods , False Negative Reactions , False Positive Reactions , Female , Humans , Male , Microtomy , Paraffin Embedding/methods , Quality Control
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