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1.
J Dairy Sci ; 107(4): 2444-2453, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37923207

RESUMEN

In North America, surplus dairy calves are sold soon after birth and often marketed through a third party (e.g., live auction, livestock dealer) before entering veal or dairy beef production. Previous work has demonstrated that a percentage of calves have failed transfer of passive immunity (FTPI) and clinical signs of disease on arrival at calf-raising facilities, but little is known regarding calf condition during marketing. The objectives of this cross-sectional study were to (1) estimate the prevalence of FTPI and poor health outcomes in surplus calves on arrival at livestock dealers, and (2) investigate the association between calf-level variables (body weight, sex, source) and health outcomes. Two livestock dealers in Ohio were visited 2 to 3 times per week, with approximately 28 calves enrolled in the study per visit for a total of 1,119 calves. One blood sample per calf was obtained to evaluate FTPI by measuring serum total protein concentrations (using a cutoff <5.1 g/dL). Calves were clinically evaluated for signs of arthritis, broken ribs or tail, dehydration, depression, diarrhea, fever, navel inflammation, and respiratory disease by 2 observers; health outcomes were dichotomized using clinically relevant cut points. Descriptive statistics were used to estimate the prevalence of calves with poor health outcomes. Multivariable logistic regression models were built to investigate the effect of body weight, sex, and source on health outcomes. Nineteen percent (206/1,091) of calves had FTPI.


Asunto(s)
Enfermedades de los Bovinos , Animales , Bovinos , Estudios Transversales , Prevalencia , Enfermedades de los Bovinos/epidemiología , Peso Corporal , Mercadotecnía
2.
Med Vet Entomol ; 35(1): 42-50, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32748973

RESUMEN

Hemalin, initially described in Haemaphysalis longicornis, is a protein with anticoagulant activity. We retrieved a gene fragment functionally annotated as hemalin from H. flava salivary gland transcriptomic library, but its full-length complementary DNA (cDNA) and antithrombogenicity have not been investigated in the species. Here we cloned the full length of hemalin (Hf-hemalin) by 3'-end rapid-amplification of cDNA ends, and the open reading frame (ORF) of Hf-hemalin was expressed in Escherichia coli. The recombinant protein (rHf-Hemalin) was tested for antithrombogenicity. The full-length of Hf-hemalin was 607 bp with an ORF of423 bp. Protein encoded by Hf-hemalin was predicted to contain 2 Kunitz domains and a signal peptide. The expression of Hf-hemalin in salivary glands, midguts and ovaries was higher in the semi-engorged than the fully engorged. Prokaryotic expression yielded a product of 40 kDa containing a glutathione S-transferase (GST) tag. Incubation of rHf-Hemalin with rat plasma significantly extended prothrombin time and activated partial thromboplastin time compared with normal saline and GST controls. Our data demonstrated that Hemalin from H. flava shared a similar primary structure with that from H. longicornis, and was also anticoagulant. Further investigations are needed to test its feasibility to be an antigen candidate for the development of vaccines against ticks.


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/genética , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos/química , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/metabolismo , Secuencia de Bases , Clonación Molecular , Femenino , Expresión Génica , Péptidos y Proteínas de Señalización Intercelular/química , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Ixodidae
3.
Med Vet Entomol ; 35(3): 513-522, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33931902

RESUMEN

In this study, the authors sequenced and characterized the complete mitochondrial (mt) genomes of two hard ticks of the genus Ixodes, I. nipponensis and Ixodes (Pholeoixodes) sp., which were 14 505 and 14 543 bp in length, respectively. Their mt genomes encoded 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNA genes and two ribosomal RNA genes, and have only one non-coding region. The gene order in their mt genomes was the same as that of other Ixodes spp. mt genomes. The average sequence identity, combined nucleotide diversity, non-synonymous/synonymous substitutions ratio analyses consistently demonstrated that cox1, rrnS, cox2, cox3 and cytb were the most conserved and atp8, nad6 and nad2 were the most variable genes across Ixodes mitogenomes. Phylogeny of the present Ixodes spp., and other selected hard tick species, based on concatenated amino acid sequences of PCGs, confirmed their position within the genus Ixodes and sub-family Ixodinae. The novel mt markers described herein will be useful for further studies of the population genetics, molecular epidemiology and systematics of hard ticks.


Asunto(s)
Genoma Mitocondrial , Ixodes , Animales , Orden Génico , Genoma Mitocondrial/genética , Ixodes/genética , Filogenia , ARN de Transferencia
4.
Zhonghua Fu Chan Ke Za Zhi ; 56(9): 616-621, 2021 Sep 25.
Artículo en Zh | MEDLINE | ID: mdl-34547862

RESUMEN

Objective: To investigate the present situation of unintended pregnancy within two years postpartum and its influencing factors in China. Methods: Participants who delivered a live birth at 60 hospitals in 15 provinces in the eastern, central and western regions of China during July 2015 to June 2016 were interviewed by using structured questionnaire. Information on occurrence of unintended pregnancy within 2 years after delivery, postpartum contraceptive use, sexual resumption, breastfeeding, and women's socio-demographic characteristics, and so on, were collected. Life-table analysis, cluster log-rank tests and a 2-level Cox regression model were used for data analysis. Results: A total of 18 045 postpartum women were investigated. The cumulative 1- and 2-year unintended pregnancy rates after delivery were 5.3% (95%CI: 4.5%-6.1%) and 13.1% (95%CI: 11.3%-14.8%), respectively. Cox regression model analysis showed that the risk of unintended pregnancy within 2 years postpartum were increased in younger women, ethnic minorities, women with abortion history, and those who had a vaginal delivery with short lactation time and late postpartum contraceptive initiation (all P<0.01). The risk of postpartum unintended pregnancy was not associated with geographic regions and hospitals where women gave a birth (all P>0.05). Conclusions: In China, the risk of unintended pregnancy within 2 years after delivery is relatively high. Service institutions and service providers should improve the quality of postpartum family planning services, promote the use of high effect contraceptive methods, and educate women to use a method at the time of their sexual resumption or even before.


Asunto(s)
Anticoncepción , Embarazo no Planeado , China/epidemiología , Servicios de Planificación Familiar , Femenino , Humanos , Incidencia , Embarazo
5.
Med Vet Entomol ; 34(2): 215-224, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31840281

RESUMEN

Melophagus ovinus is a type of ectoparasite infesting sheep. Data regarding the comprehensive bacterial community associated with the whole body and midgut of M. ovinus under different engorged statuses are required. Melophagus ovinus were collected from the city of Jiuquan, China. Bacterial DNA was extracted from the whole body and midgut of fully engorged female adults, or newly hatched and unfed adult female M. ovinus. The 16S rRNA gene V3-V4 hypervariable regions were sequenced using the IonS5™XL platform (Thermo Fisher Scientific, Waltham, MA, U.S.A.). The whole body bacterial diversity of the newly hatched, unfed adult females was greater compared with that of the other three samples. Proteobacteria was the dominant bacterial phylum in all of the samples. Of the 42 total bacterial genera present in all of the experimental samples, Arsenophonus, Bartonella and Wolbachia were the dominant genera. The relative abundance of Arsenophonus in midgut was greater than that in the whole body. The relative abundance of Bartonella in fully engorged adults was far greater than those in newly hatched, unfed adults. The relative abundance of Wolbachia was highest in the whole body of newly hatched, unfed adults. Seventeen bacterial species were identified in all experimental samples. Bartonella chomelii, Streptococcus hyointestinalis and Escherichia coli were the first species reported in M. ovinus.


Asunto(s)
Bacterias/aislamiento & purificación , Dípteros/microbiología , Microbiota , Animales , China , ADN Bacteriano/análisis , Conducta Alimentaria , Femenino , Microbioma Gastrointestinal , ARN Ribosómico 16S/análisis
6.
Med Vet Entomol ; 34(2): 229-235, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31433511

RESUMEN

Amblyomma javanense is an important ectoparasite of Manis javanica, although the population genetics, molecular biology and systematics of A. javanense remain poorly understood. In the present study, the mitochondrial genome of A. javanense was sequenced using the Illumina HiSeq sequencing platform (Illumina, San Diego, CA, U.S.A.) and compared with the genomes of two closely related species: Amblyomma fimbriatum and Amblyomma americanum. The intraspecies and interspecies relationships of A. javanense and another 21 selected species were investigated by constructing a maximum-likelihood tree and a neighbour-joining tree. The mitochondrial genome of A. javanense was 14 780 bp in length and contained 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes and two control regions. The results of the comparisons indicate that there is great similarity among these three species, and both trees indicate that A. javanense is a member of the Amblyomminae. The study of A. javanense of pangolins also indicates the premise and foundation of the relationship between the parasite and other species.


Asunto(s)
Genoma de los Insectos , Genoma Mitocondrial , Ixodidae/genética , Animales , China , Femenino , Masculino
7.
Med Vet Entomol ; 34(2): 192-200, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31802518

RESUMEN

The heat shock protein 70 (HSPA) family and their genes have been studied in ticks and are considered as possible antigen candidates for the development of anti-tick vaccines. However, knowledge about their members, structure and function in ticks is incomplete. Based on our transcriptomic data, the full length of four HSPA genes in Haemaphysalis flava (Acari: Ixodidae) was cloned via rapid amplification of cDNA ends. The open reading frame of HSPA2A, HSPA2B, HSPA5 and HSPA9 was 1920, 1911, 1983 and 2088 bp in length, respectively. Three family signatures and one localization motif were in the encoding proteins. HSPA2A and HSPA2B were predicted to be located at cytoplasm/nucleus, whereas HSPA5 and HSPA9 were at endoplasmic reticulum and mitochondria, respectively. In silico simulation demonstrated that those proteins had distinct numbers of α-helixes, extended strands and coils, and different antigenic epitopes. Expression of HSPA5 and HSPA9 in the salivary gland was significantly higher in partially-engorged female adult ticks than the fully-engorged (P < 0.01) as shown by a quantitative polymerase chain reaction. Our data indicated that H. flava ticks had at least four HSPA genes encoding proteins with different cellular locations, structures and expression profiles, suggesting their diverse roles in tick biology.


Asunto(s)
Proteínas de Artrópodos/genética , Proteínas HSP70 de Choque Térmico/genética , Ixodidae/genética , Familia de Multigenes , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos/química , Proteínas de Artrópodos/metabolismo , Clonación Molecular , Femenino , Proteínas HSP70 de Choque Térmico/química , Proteínas HSP70 de Choque Térmico/metabolismo , Ixodidae/metabolismo
9.
J Helminthol ; 90(1): 1-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25226270

RESUMEN

The present study examined sequence variability in two mitochondrial DNA (mtDNA) regions, namely cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1), and internal transcribed spacer (ITS) of nuclear ribosomal DNA (rDNA) among Oesophagostomum asperum isolates from goats in Hunan Province, China. A portion of the cox1 (pcox1), nad1 (pnad1) genes and the ITS (ITS1+5.8S rDNA+ITS2) rDNA were amplified by polymerase chain reaction (PCR) separately from adult O. asperum individuals and the representative amplicons were subjected to sequencing from both directions. The lengths of pcox1, pnad1 and ITS rDNA were 366 bp, 681 bp and 785 bp, respectively. The A+T contents of gene sequences were 71.5-72% for pcox1, 73.7-74.2% for pnad1 and 58-58.8% for ITS rDNA. Intra-specific sequence variations within O. asperum were 0-1.6% for pcox1, 0-1.9% for pnad1 and 0-1.7% for ITS rDNA, while inter-specific sequence differences among members of the genus Oesophagostomum were significantly higher, being 11.1-12.5%, 13.3-17.7% and 8.5-18.6% for pcox1, pnad1 and ITS rDNA, respectively. Phylogenetic analyses using combined sequences of pcox1 and pnad1, with three different computational algorithms (Bayesian inference, maximum likelihood and maximum parsimony), revealed distinct groups with high statistical support. These findings demonstrated the existence of intra-specific variation in mtDNA and rDNA sequences among O. asperum isolates from goats in Hunan Province, China, and have implications for studying molecular epidemiology and population genetics of O. asperum.


Asunto(s)
ADN de Helmintos/genética , ADN Mitocondrial/genética , Variación Genética , Enfermedades de las Cabras/parasitología , Esofagostomiasis/veterinaria , Oesophagostomum/genética , Animales , Secuencia de Bases , China , Femenino , Cabras , Masculino , Datos de Secuencia Molecular , Esofagostomiasis/parasitología , Oesophagostomum/clasificación , Oesophagostomum/aislamiento & purificación , Filogenia
10.
J Exp Med ; 192(7): 965-76, 2000 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-11015438

RESUMEN

T cells recognize microbial glycolipids presented by CD1 proteins, but there is no information regarding the generation of natural glycolipid antigens within infected tissues. Therefore, we determined the molecular basis of CD1b-restricted T cell recognition of mycobacterial glycosylated mycolates, including those produced during tissue infection in vivo. Transfection of the T cell receptor (TCR) alpha and beta chains from a glucose monomycolate (GMM)-specific T cell line reconstituted GMM recognition in TCR-deficient T lymphoblastoma cells. This TCR-mediated response was highly specific for natural mycobacterial glucose-6-O-(2R, 3R) monomycolate, including the precise structure of the glucose moiety, the stereochemistry of the mycolate lipid, and the linkage between the carbohydrate and the lipid. Mycobacterial production of antigenic GMM absolutely required a nonmycobacterial source of glucose that could be supplied by adding glucose to media at concentrations found in mammalian tissues or by infecting tissue in vivo. These results indicate that mycobacteria synthesized antigenic GMM by coupling mycobacterial mycolates to host-derived glucose. Specific T cell recognition of an epitope formed by interaction of host and pathogen biosynthetic pathways provides a mechanism for immune response to those pathogenic mycobacteria that have productively infected tissues, as distinguished from ubiquitous, but innocuous, environmental mycobacteria.


Asunto(s)
Antígenos Bacterianos/inmunología , Antígenos CD1/inmunología , Carbohidratos/inmunología , Glucolípidos/inmunología , Mycobacterium/inmunología , Linfocitos T/inmunología , Animales , Armadillos , Conformación de Carbohidratos , Carbohidratos/química , Humanos , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Estereoisomerismo , Relación Estructura-Actividad , Células Tumorales Cultivadas
11.
Diabetes Metab ; 46(6): 450-460, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32387700

RESUMEN

BACKGROUND: Diabetes is a chronic disease associated with a variety of complications, and nudging may be a potential solution to improve diabetes control. Since nudging is a new concept, no review of literature on nudging diabetic patients into improving their health behaviour has been done. Therefore, we aim to collate a list of nudge intervention and determine the context in which nudging is successful. METHODS: We adopted a two-arm search strategy comprising the search of literature databases and snowballing using relevant search terms. We summarized patient characteristics, the nudge intervention, according to nudging strategies, delivery mode and their outcomes. The conditions present in effective nudge interventions were assessed and reported. RESULTS: We retrieved 11,494 studies from our searches and included 33. An additional five studies were added through snowballing. Studies included utilized framing (n=5), reminders (n=10), gamification (n=2), social modelling (n=5) and social influence (n=16). Studies on reminders and gamification were more likely to have a statistically significant outcome. The targeted health behaviours identified were medication adherence, physical activity, diet, blood glucose monitoring, foot care, self-efficacy, HbA1c and quality of life. Of these, studies with adherence to medication, foot care practice and quality of life as targeted health behaviours were more likely to show a statistically significant outcome. CONCLUSION: Nudging has shown potential in changing health behaviour of patients with diabetes in specific context. We identified two possible factors (delivery mode and patient characteristics) that may affect the effectiveness of nudge intervention.


Asunto(s)
Conducta de Elección , Diabetes Mellitus/terapia , Economía del Comportamiento , Conductas Relacionadas con la Salud , Autocuidado , Automonitorización de la Glucosa Sanguínea , Atención a la Salud , Dieta , Ejercicio Físico , Juegos Recreacionales , Humanos , Cumplimiento de la Medicación , Influencia de los Compañeros , Calidad de Vida , Sistemas Recordatorios , Autoeficacia
12.
Ann Surg Oncol ; 16(4): 953-61, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19184236

RESUMEN

BACKGROUND: This study aims to determine what effect correcting melphalan dosing for ideal body weight (IBW) has on toxicity and response in isolated limb infusion (ILI) in patients with advanced extremity melanoma. METHODS: This was an open observational study examining whether correcting the melphalan dose for IBW will influence response and toxicity in patients undergoing ILI for advanced extremity melanoma in 41 patients undergoing 42 procedures (13 without correction for IBW; and 29 with correction for IBW). Melphalan pharmacokinetics, limb toxicity, serologic toxicity, and response at 3 months were compared. RESULTS: The corrected group had a lower estimated limb volume (V (esti)) to melphalan volume at steady state (V (ss)) (P < .0001) ratio as well as lower incidence of grade > or =3 regional toxicity, serologic toxicity, and compartment syndrome (P = .0249, P = .027, P = .02). There was a positive correlation of V (esti)/V (ss) to toxicity (P = .0127, r = .382). No significant difference in response (P = .3609) between the groups was found, although there was a trend of association between V (esti)/V (ss) and response (P = .051, r = .3383). CONCLUSIONS: Correcting for IBW in ILI lowers toxicity without significantly altering response rates.


Asunto(s)
Antineoplásicos Alquilantes/farmacocinética , Melfalán/farmacocinética , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos Alquilantes/administración & dosificación , Peso Corporal , Quimioterapia del Cáncer por Perfusión Regional , Relación Dosis-Respuesta a Droga , Extremidades , Femenino , Humanos , Masculino , Melanoma/tratamiento farmacológico , Melfalán/administración & dosificación , Persona de Mediana Edad , Neoplasias Cutáneas/tratamiento farmacológico
13.
Science ; 198(4314): 306-7, 1977 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-17770507

RESUMEN

Douglas fir plantlets were produced in tissue culture under defined conditions from cotyledon explants obtained from 2- to 4-week-old seedlings. Tissue pieces were cultured on the surface of a fabric tissue support (100 percent polyester) saturated with liquid nutrient medium; this facilitated periodic changes of the medium to meet the requirements at successive developmental stages without transfer of cultured tissues. Plant growth regulators were needed to stimulate adventitious bud formation. Plantlets were regenerated by rooting excised shoots at 19 degrees C on agarsolidified medium containing sucrose and the auxin naphthalene-2-acetic acid. After root initiation, plant growth regulators were removed; this resulted in stimulation of root elongation and the subsequent development of plantlets, which were then established in soil.

14.
Trop Biomed ; 36(1): 297-303, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33597450

RESUMEN

The cattle tick, Rhipicephalus microplus (formerly Boophilus microplus), is the most important blood-feeding ectoparasite of cattle in tropical and subtropical regions of the world. In this study, we examined sequence variability in three mitochondrial (mt) DNA (cox1, nad1, nad4) among cattle tick R. microplus originating from four provinces of China. A portion of cox1 (pcox1), nad1 (pnad1) and nad4 (pnad4) genes were amplified by polymerase chain reaction (PCR) separately from adult R. microplus individuals and the amplicons were subjected to sequence from both directions. The sequence of mt cox1, nad1, nad4 genes was 817 bp, 350 bp, and 794 bp in size, respectively. The intraspecific sequence variations within R. microplus were 0-8.6% for cox1, 0-4.9% for nad1 and 0-10.3% for nad4. However, the interspecific sequence differences among the members of the Rhipicephalus [R. sanguineus (JX416325) and R. turanicus (NC035946)] were significantly higher, being 16.9-20.5%, 18- 22.8%, 22.8-25.3% for pcox1, pnad1 and pnad4, respectively. In addition, genetic differences were 7.9-8.6% for cox1, 4.3-4.9% for nad1 and 10-10.3% for nad4 between the two detected lineages (R. microplus clade A and clade B). Phylogenetic analyses indicated that all the Rhipicephalus isolates from the present study represents R. microplus, supporting that R. microplus represents species complex. Our result provided an additional genetic evidence for the existence of species complex within R. microplus in China.

15.
Oncogene ; 36(29): 4234, 2017 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-28319058

RESUMEN

This corrects the article DOI: 10.1038/onc.2015.397.

16.
Tob Control ; 15(3): 160-5, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16728745

RESUMEN

OBJECTIVES: To assess the magnitude of cigarette smuggling after the market opened in Taiwan. METHODS: Review of tobacco industry documents for references to smuggling activities related to Taiwan and government statistics on seizure of smuggled cigarettes. RESULTS: The market opening in 1987 led to an increase in smuggling. Contraband cigarettes became as available as legal ones, with only a small fraction (8%) being seized. Being specifically excluded from the market-opening, Japan entered the Taiwan market by setting up a Swiss plant as a legal cover for smuggling 10-20 times its legal quota of exports to Taiwan. Smuggling in Taiwan contributed to increased consumption of foreign brands, particularly by the young. Taiwan, not a member of the World Health Organization, was excluded from the East Asian 16-member "Project Crocodile", a regional anti-smuggling collaborative effort to implement the Framework Convention on Tobacco Control. CONCLUSIONS: Taiwan showed a sharp increase in smuggling after market liberalisation. Being excluded from the international community, Taiwan faces an uphill battle to fight smuggling alone. If Taiwan remained as its weakest link, global efforts to reduce tobacco use will be undermined, particularly for countries in the East Asian region.


Asunto(s)
Comercio/estadística & datos numéricos , Crimen/estadística & datos numéricos , Nicotiana , Adolescente , Adulto , Comportamiento del Consumidor/estadística & datos numéricos , Femenino , Humanos , Masculino , Fumar/epidemiología , Taiwán/epidemiología , Industria del Tabaco
17.
Trop Biomed ; 33(4): 663-667, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33579062

RESUMEN

Ticks are vectors of diseases that affect humans and animals worldwide. In current study, the intestinal bacterial flora associated with the blood feeding ticks (Haemaphysalis flava, Haemaphysalis longicornis, Rhipicephalus haemaphysaloides, Boophilus microplus and Dermacentor sinicus) were analyzed using polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) and then sequenced. The five ticks were collected from cattle, dog, hedgehog and goats in Fujian, Shandong, Henan, Jiangxi, Hunan, Shanxi and Guangxi provinces, China. Our results show that nine distinct DGGE bands were found using PCR-DGGE method. Sequences analyses indicated that they belonged to Rickettsia peacockii, Rickettsia raoultii, Rickettsia helvetica, Rickettsia slovaca, Rickettsia tarasevichiae, Coxiella sp., Erwinia sp., Klebsiella pneumoniae and Pseudomonas aeruginos. The present results indicate that zoonotic pathogens are present in ticks in many provinces of China. This useful information will aid in the epidemiology of tick-borne zoonotic diseases in China as well as in raising awareness to avoid tick bites is an important measure to prevent the infection and transmission of zoonotic pathogens.

18.
Oncogene ; 35(26): 3387-98, 2016 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-26500058

RESUMEN

Secondary mutation of epidermal growth factor receptor (EGFR) resulting in drug resistance is one of the most critical issues in lung cancer therapy. Several drugs are being developed to overcome EGFR tyrosine kinase inhibitor (TKI) resistance. Here, we report that pyruvate kinase M2 (PKM2) stabilized mutant EGFR protein by direct interaction and sustained cell survival signaling in lung cancer cells. PKM2 silencing resulted in markedly reduced mutant EGFR expression in TKI-sensitive or -resistant human lung cancer cells, and in inhibition of tumor growth in their xenografts, concomitant with downregulation of EGFR-related signaling. Mechanistically, PKM2 directly interacted with mutant EGFR and heat-shock protein 90 (HSP90), and thus stabilized EGFR by maintaining its binding with HSP90 and co-chaperones. Stabilization of EGFR relied on dimeric PKM2, and the protein half-life of mutant EGFR decreased when PKM2 was forced into its tetramer form. Clinical levels of PKM2 positively correlated with mutant EGFR expression and with patient outcome. These results reveal a previously undescribed non-glycolysis function of PKM2 in the cytoplasm, which contribute to EGFR-dependent tumorigenesis and provide a novel strategy to overcome drug resistance to EGFR TKIs.


Asunto(s)
Receptores ErbB/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Neoplasias Pulmonares/metabolismo , Piruvato Quinasa/metabolismo , Células A549 , Animales , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Citosol/enzimología , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Humanos , Immunoblotting , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Mutación , Unión Proteica , Inhibidores de Proteínas Quinasas/farmacología , Estabilidad Proteica , Piruvato Quinasa/genética , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Supervivencia , Carga Tumoral/efectos de los fármacos , Carga Tumoral/genética , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Tob Control ; 14 Suppl 1: i23-7, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15923443

RESUMEN

OBJECTIVE: To assess the impact of smoking disparities on health disparities, in terms of gap in life expectancy, in Taiwan cities and counties. METHODS: Using the decomposition method of life expectancy, the contribution of each disease category to the life expectancy gap was quantitatively expressed as the number of years of life. The smoking attributable fraction (SAF) was calculated for each city and county based on their respective smoking prevalence and relative risk for each smoking related disease. The smoking attributable gap (SAG) in life expectancy between two sites is the sum of the difference in SAF between two sites for each smoking related disease multiplied by the number of years this disease contributed to the life expectancy gap. RESULTS: Significant health and smoking disparities were present among the 23 cities and counties in Taiwan. These health disparities and smoking disparities were highly correlated (R2 = 0.3676). Generally, the health gap increased with increasing smoking disparity. The disparity in smoking prevalence and intensity among cities and counties in Taiwan was responsible for up to 19% of the health disparity. The health disparity is also highly correlated (R2 = 0.3745) with SAG in life expectancy. CONCLUSIONS: Reducing smoking is important to health, and reducing the smoking disparity is also important for reducing the health disparity observed in Taiwan. The larger the health disparity is, the more important the smoking attributable disparity could be. The reduction of smoking disparities could be a realistic and cost effective way toward reducing health disparities.


Asunto(s)
Esperanza de Vida , Fumar/epidemiología , Causas de Muerte , Estado de Salud , Humanos , Estudios Longitudinales , Prevalencia , Factores de Riesgo , Salud Rural , Fumar/mortalidad , Prevención del Hábito de Fumar , Factores Socioeconómicos , Taiwán/epidemiología , Salud Urbana
20.
Tob Control ; 14 Suppl 1: i33-7, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15923446

RESUMEN

OBJECTIVE: To estimate productivity losses and financial costs to employers caused by cigarette smoking in the Taiwan workplace. METHODS: The human capital approach was used to calculate lost productivity. Assuming the value of lost productivity was equal to the wage/salary rate and basing the calculations on smoking rate in the workforce, average days of absenteeism, average wage/salary rate, and increased risk and absenteeism among smokers obtained from earlier research, costs due to smoker absenteeism were estimated. Financial losses caused by passive smoking, smoking breaks, and occupational injuries were calculated. RESULTS: Using a conservative estimate of excess absenteeism from work, male smokers took off an average of 4.36 sick days and male non-smokers took off an average of 3.30 sick days. Female smokers took off an average of 4.96 sick days and non-smoking females took off an average of 3.75 sick days. Excess absenteeism caused by employee smoking was estimated to cost USD 178 million per annum for males and USD 6 million for females at a total cost of USD 184 million per annum. The time men and women spent taking smoking breaks amounted to nine days per year and six days per year, respectively, resulting in reduced output productivity losses of USD 733 million. Increased sick leave costs due to passive smoking were approximately USD 81 million. Potential costs incurred from occupational injuries among smoking employees were estimated to be USD 34 million. CONCLUSIONS: Financial costs caused by increased absenteeism and reduced productivity from employees who smoke are significant in Taiwan. Based on conservative estimates, total costs attributed to smoking in the workforce were approximately USD 1032 million.


Asunto(s)
Absentismo , Eficiencia Organizacional/economía , Fumar/economía , Costos y Análisis de Costo/métodos , Femenino , Humanos , Masculino , Enfermedades Profesionales/economía , Enfermedades Profesionales/epidemiología , Prevalencia , Fumar/efectos adversos , Fumar/epidemiología , Taiwán/epidemiología , Lugar de Trabajo
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