RESUMEN
The potato tuberworm moth (PTM) Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) is one of the most damaging pests of potato Solanum tuberosum L. in warm temperate and subtropical areas. Our previous experiment showed that extracts of larval frass of PTM deterred oviposition of conspecific females. In this study, we investigated the identification of chemicals in larval frass that were influencing the oviposition of PTM by behavioral bioassays and electroantennography analysis in the laboratory. Frass was collected from third and fourth instar larvae and combined analysis of gas chromatography coupled with electroantennography (GC-EAD) of dichloromethane extracts showed that eight compounds from larval frass extracts elicited repeatable antennal responses from mated females. Seven EAD-active compounds in frass volatile extract were identified by gas chromatography-mass spectrometry (GC-MS) as linoleic acid, octadecanoic acid, tricosane, pentacosane, heptacosane, nonacosane, and cholesterol. Oviposition bioassays indicated that frass extracts had a deterrent effect on egg laying, the deterrent activity increased with the concentration of frass extracts, and the threshold value for statistical significance in oviposition deterrence was in the range of 20-200 mg frass per cage. Linoleic acid, pentacosane, heptacosane, nonacosane, and cholesterol in larval frass volatiles were found to play a key role in repelling oviposition in a dose-dependent manner. We suggest that the bioactive compounds in larval frass are responsible for repelling oviposition of PTM, and n-alkanes, especially pentacosane, strongly deter oviposition and may be considered as a potential oviposition deterrent for potential applications.
Asunto(s)
Heces/química , Larva/química , Mariposas Nocturnas/química , Oviposición , Compuestos Orgánicos Volátiles/química , Animales , Femenino , Cromatografía de Gases y Espectrometría de Masas , Repelentes de Insectos , Solanum tuberosumRESUMEN
Glycosphingolipid biosynthesis-globo series pathway genes (FUT1, FUT2, ST3GAL1, HEXA, HEXB, B3GALNT1, and NAGA) play an important regulatory role in the defense against Escherichia coli F18 in piglets. In this study, we identified the transcription initiation site and promoter of this gene cluster by mined previous RNA-seq results using bioinformatics tools. The FUT1 transcription initiation region included five alternative splicing sites and two promoter regions, whereas each of the six other genes had one promoter. Dual luciferase reporter results revealed significantly higher transcriptional activity by FUT1 promoter 2, indicating that it played a more important role in transcription. The promoters of glycosphingolipid biosynthesis genes identified contained a CpG island within the first 500 bp, except for the B3GALNT1 promoter which included fewer CpG sites. These results provide a deeper insight into methylation and the regulatory mechanisms of glycosphingolipid biosynthesis-globo series pathway genes in piglets.
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Fucosiltransferasas/genética , Glicoesfingolípidos/biosíntesis , Regiones Promotoras Genéticas , Porcinos/genética , Animales , Islas de CpG , Metilación de ADN , Fucosiltransferasas/metabolismo , Activación Transcripcional , Galactósido 2-alfa-L-FucosiltransferasaRESUMEN
We evaluated the efficacy and safety of tacrolimus (TAC) combined with corticosteroids in treating patients with idiopathic membranous nephropathy (IMN). One hundred seventy-seven biopsy-proven IMN patients were recruited in this retrospective clinical study. Sixty patients received TAC (target blood concentration of 4-8 ng/mL) and 117 patients received daily cyclophosphamide (CYC, 100 mg) combined with prednisone. Remission rates at the end of the first, second and third month in the TAC group were significantly higher than that in the CYC group (1st: 35.0 vs 19.7%, P<0.05; 2nd: 56.7 vs 38.5%, P<0.05; 3rd: 76.7 vs 59.0%, P<0.05). In the first 3 months, daily urinary protein and serum albumin in the TAC group obtained a better improvement than that in the CYC group (P<0.05). At the end of the sixth and the twelfth month, the remission rates, daily urinary protein and serum albumin were all comparable between the two groups (P>0.05). No significant difference of relapse rate between the groups was found (16.3 vs 12.0%, P>0.05). Patients were more likely to develop glucose intolerance in the TAC group. The TAC regimen obtained more benefits in treating IMN patients, especially in the first 3 months, than the CYC regimen.
Asunto(s)
Corticoesteroides/administración & dosificación , Ciclofosfamida/administración & dosificación , Glomerulonefritis Membranosa/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Prednisona/administración & dosificación , Tacrolimus/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Creatinina/sangre , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Proteinuria , Reproducibilidad de los Resultados , Estudios Retrospectivos , Albúmina Sérica/análisis , Factores de Tiempo , Resultado del Tratamiento , Adulto JovenRESUMEN
We evaluated the efficacy and safety of tacrolimus (TAC) combined with corticosteroids in treating patients with idiopathic membranous nephropathy (IMN). One hundred seventy-seven biopsy-proven IMN patients were recruited in this retrospective clinical study. Sixty patients received TAC (target blood concentration of 4–8 ng/mL) and 117 patients received daily cyclophosphamide (CYC, 100 mg) combined with prednisone. Remission rates at the end of the first, second and third month in the TAC group were significantly higher than that in the CYC group (1st: 35.0 vs 19.7%, P<0.05; 2nd: 56.7 vs 38.5%, P<0.05; 3rd: 76.7 vs 59.0%, P<0.05). In the first 3 months, daily urinary protein and serum albumin in the TAC group obtained a better improvement than that in the CYC group (P<0.05). At the end of the sixth and the twelfth month, the remission rates, daily urinary protein and serum albumin were all comparable between the two groups (P>0.05). No significant difference of relapse rate between the groups was found (16.3 vs 12.0%, P>0.05). Patients were more likely to develop glucose intolerance in the TAC group. The TAC regimen obtained more benefits in treating IMN patients, especially in the first 3 months, than the CYC regimen.
Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Adulto Joven , Corticoesteroides/administración & dosificación , Ciclofosfamida/administración & dosificación , Glomerulonefritis Membranosa/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Prednisona/administración & dosificación , Tacrolimus/administración & dosificación , Creatinina/sangre , Quimioterapia Combinada , Estudios de Seguimiento , Proteinuria , Reproducibilidad de los Resultados , Estudios Retrospectivos , Albúmina Sérica/análisis , Factores de Tiempo , Resultado del TratamientoRESUMEN
To preliminarily clarify the mechanism of cardiac microvascular endothelial barrier function leading to heart failure, primary HMVEC-D cells were selected and cultured for amplification. The cells were infected with adenovirus vector containing the ADP-ribosylation factor 6 (Arf6) Q67L gene. Full-length and functional fragments of myeloid differentiation primary response 88 and ARF nucleotide-binding site opener genes were established and transfected into HEK293T cells. GTP-Arf6 pull-down experiment, fluorescent quantitative real-time PCR, immuno-coprecipitation, and transendothelial electrical resistance analysis were conducted. Interleukin-1ß (IL-1ß) induced increase in vascular permeability, whereas inhibitor SC514 blocked IL-1ß-induced transfer of nuclear factor-κB into the nucleus, from the cytoplasm. Increase in amount of activated Arf6 promoted reduction in transendothelial electrical resistance. In addition, SecinH3 significantly inhibited increase in vascular permeability, and the progression of heart failure was significantly relieved. Cardiac microvascular endothelial barrier function can lead to heart failure. However, IL-1ß induced increase in vascular permeability, which nullified the function of cardiac microvascular endothelial barrier. These findings are closely related to the activation of the Arf6-VE-cadherin signaling pathway.
Asunto(s)
Células Endoteliales/metabolismo , Microvasos/citología , Miocardio/citología , Factor 6 de Ribosilación del ADP , Factores de Ribosilacion-ADP/metabolismo , Permeabilidad Capilar/efectos de los fármacos , Permeabilidad de la Membrana Celular/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Células HEK293 , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/fisiopatología , Humanos , Interleucina-1beta/farmacologíaRESUMEN
One hundred and six accessions of hawthorn intraspecific resources, from the National Germplasm Repository at Shenyang, were subjected to genetic diversity and principal component analysis based on evaluation data of 15 fruit traits. Results showed that the genetic diversity of hawthorn fruit traits varied. Among the 15 traits, the fruit shape variable coefficient had the most obvious evaluation, followed by fruit surface state, dot color, taste, weight of single fruit, sepal posture, peduncle form, and metula traits. These are the primary traits by which hawthorn could be classified in the future. The principal component demonstrated that these traits are the most influential factors of hawthorn fruit characteristics.
Asunto(s)
Crataegus/genética , Frutas , Variación Genética , Carácter Cuantitativo Heredable , Estudios de Asociación Genética , Fenotipo , Análisis de Componente Principal , Banco de SemillasRESUMEN
This study aims to explore the roles of somatic embryogenesis receptor-like kinase (SERK) in Malus hupehensis (Pingyi Tiancha). The full-length sequences of SERK1 in triploid Pingyi Tiancha (3n) and a tetraploid hybrid strain 33# (4n) were cloned, sequenced, and designated as MhSERK1 and MhdSERK1, respectively. Multiple alignments of amino acid sequences were conducted to identify similarity between MhSERK1 and MhdSERK1 and SERK sequences in other species, and a neighbor-joining phylogenetic tree was constructed to elucidate their phylogenetic relations. Expression levels of MhSERK1 and MhdSERK1 in different tissues and developmental stages were investigated using quantitative real-time PCR. The coding sequence lengths of MhSERK1 and MhdSERK1 were 1899 bp (encoding 632 amino acids) and 1881 bp (encoding 626 amino acids), respectively. Sequence analysis demonstrated that MhSERK1 and MhdSERK1 display high similarity to SERKs in other species, with a conserved intron/exon structure that is unique to members of the SERK family. Additionally, the phylogenetic tree showed that MhSERK1 and MhdSERK1 clustered with orange CitSERK (93%). Furthermore, MhSERK1 and MhdSERK1 were mainly expressed in the reproductive organs, in particular the ovary. Their expression levels were highest in young flowers and they differed among different tissues and organs. Our results suggest that MhSERK1 and MhdSERK1 are related to plant reproduction, and that MhSERK1 is related to apomixis in triploid Pingyi Tiancha.
Asunto(s)
Flores/genética , Malus/genética , Filogenia , Secuencia de Aminoácidos/genética , Proteínas de Arabidopsis/genética , Clonación Molecular , Flores/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas , Malus/crecimiento & desarrollo , Proteínas de Plantas/biosíntesis , Proteínas de Plantas/genética , Proteínas Quinasas/genética , Alineación de Secuencia , Tetraploidía , TriploidíaRESUMEN
Preliminary studies have suggested that a characteristic element of the matrix attachment region (MAR) in human interferon-ß mediates the adhesion of vectors to Chinese hamster ovary (CHO) cells. In this study, we investigated if vector adhesion increased nerve growth factor (NGF) expression in CHO cells. The MAR characteristic element sequence of human interferon-ß was inserted into the multiple-cloning site of the pEGFP-C1 vector. The target NGF gene was inserted upstream of the MAR characteristic element sequence to construct the MAR/NGF expression vector. The recombinant plasmid was transfected into CHO cells and stable monoclonal cells were selected using G418. NGF mRNA and protein expression was detected by reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Plasmid reduction experiments were used to determine the state of transfected plasmid in mammalian cells. The insertion of MAR into the vector increased NGF expression levels in CHO cells (1.93- fold) compared to the control. The recombinant plasmid expressing the MAR sequence was digested into a linear space vector. The inserted MAR and NGF sequences were consistent with those inserted into the plasmid before recombination. Therefore, we concluded that the MAR characteristic element mediates vector adhesion to CHO cells and enhances the stability and efficiency of the target gene expression.
Asunto(s)
Regulación de la Expresión Génica , Vectores Genéticos/genética , Regiones de Fijación a la Matriz , Factor de Crecimiento Nervioso/genética , Animales , Células CHO , Cricetulus , Orden Génico , Plásmidos/genéticaRESUMEN
Few studies have examined the genes related to risk fac-tors that may contribute to intracranial aneurysms (IAs). This study in Chinese patients aimed to explore the relationship between IA and 28 gene loci, proven to be associated with risk factors for IA. We recruited 119 patients with aneurysms and 257 controls. Single factor and logistic regression models were used to analyze the association of IA and IA rup-ture with risk factors. Twenty-eight single nucleotide polymorphisms (SNPs) in 22 genes were genotyped for the patient and control groups. SNP genotypes and allele frequencies were analyzed by the chi-square test. Logistic regression analysis identified hypertension as a factor that increased IA risk (P = 1.0 x 10(-4); OR, 2.500; 95%CI, 1.573-3.972); IA was associated with two SNPs in the TSLC2A9 gene: rs7660895 (P = 0.007; OR, 1.541; 95%CI, 1.126-2.110); and in the TOX gene: rs11777927 (P = 0.013; OR, 1.511; 95%CI, 1.088-2.098). Subsequent removal of the influence of family relationship identified between 12 of 119 patients enhanced the significant association of these SNPs with IA (P = 0.001; OR, 1.691; 95%CI, 1.226-2.332; and P = 0.006; OR, 1.587; 95%CI, 1.137-2.213 for rs7660895 and rs11777927, respectively). Fur-thermore, the minor allele of rs7660895 (A) was also associated with IA rupture (P = 0.007; OR, 2.196; 95%CI, 1.230-3.921). Therefore, hypertension is an independent risk factor for IA. Importantly, the TSL-C2A9 (rs7660895) and TOX (rs11777927) gene polymorphisms may be associated with formation of IAs, and rs7660895 may be associated with IA rupture.
Asunto(s)
Aneurisma Roto/genética , Proteínas Facilitadoras del Transporte de la Glucosa/genética , Proteínas del Grupo de Alta Movilidad/genética , Hipertensión/genética , Aneurisma Intracraneal/genética , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Alelos , Aneurisma Roto/etnología , Aneurisma Roto/patología , Pueblo Asiatico , Estudios de Casos y Controles , Femenino , Expresión Génica , Frecuencia de los Genes , Sitios Genéticos , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Proteínas del Grupo de Alta Movilidad/metabolismo , Humanos , Hipertensión/etnología , Hipertensión/patología , Aneurisma Intracraneal/etnología , Aneurisma Intracraneal/patología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factores de RiesgoRESUMEN
We investigated the effects of different directions of insertion of matrix attachment region (MAR) sequences on transgenic expression in stably transformed Chinese hamster ovary (CHO) cells. The MAR sequences were inserted in forward or reverse directions into the expression vectors, and transfected into CHO cells. The expression of the chloramphenicol acetyltransferase (CAT) reporter gene and the relative copy numbers of the CAT gene were analyzed. The CAT gene expression levels in the vector with the MAR sequence inserted in the forward or reverse directions increased compared with expression without the MAR sequence. The relative copy numbers of the CAT gene with MAR sequenced vectors inserted in the reverse and forward directions were lower, than in the control group. The direction of insertion of MAR sequences had no significant effect on expression levels. The expression levels were not proportional to the copy numbers of the gene.
Asunto(s)
Cloranfenicol O-Acetiltransferasa/genética , ADN Intergénico/genética , Vectores Genéticos/química , Regiones de Fijación a la Matriz , Plásmidos/química , Animales , Células CHO , Línea Celular Transformada , Cloranfenicol O-Acetiltransferasa/metabolismo , Cricetulus , ADN Intergénico/metabolismo , Dosificación de Gen , Regulación de la Expresión Génica , Genes Reporteros , Vectores Genéticos/metabolismo , Plásmidos/metabolismo , TransgenesRESUMEN
The super antibiotic bactericidal/permeability-increasing (BPI) protein is a member of a new generation of proteins that have been implicated as endotoxin-neutralizing agents. In this study, recombinant porcine BPI protein was obtained by generating porcine BPI encoding prokaryotic, eukaryotic, and yeast expression vectors. Recombinant protein expression was detected in yeast GS115, Escherichia coli, and 293-6E cells by gel electrophoresis and Western blotting. Escherichia coli F18 is the primary Gram-negative bacteria in the gut and the main pathogen leading to diarrhea and edema dis-ease in weaning piglets. Therefore, E. coli F18-resistant and -sensitive Sutai piglets were used to test differential expression of BPI protein by Western blotting and to investigate the potential correlation between BPI protein expression and E. coli F18-susceptibility. Recombinant porcine BPI protein expression was not detected in the prokaryotic and yeast expression systems; however, soluble protein was detected in the eukaryotic expression system. These data indicate the strong bacterio-static action of the BPI protein and confirm the feasibility of obtaining large amounts of recombinant porcine BPI recombinant protein using this eukaryotic expression system. In addition, the BPI protein expres-sion levels in the E. coli F18-resistant group were significantly higher than those in the sensitive group, indicating that high BPI protein ex-pression is associated with resistance to E. coli F18. Our findings pro-vide a basis for further investigations into the development of a drug designed to confer resistance to E. coli F18 in weaning piglets.
Asunto(s)
Péptidos Catiónicos Antimicrobianos/biosíntesis , Proteínas Sanguíneas/biosíntesis , Resistencia a la Enfermedad/genética , Infecciones por Escherichia coli/genética , Escherichia coli/genética , Animales , Péptidos Catiónicos Antimicrobianos/genética , Proteínas Sanguíneas/genética , Susceptibilidad a Enfermedades/microbiología , Susceptibilidad a Enfermedades/veterinaria , Endotoxinas/genética , Endotoxinas/metabolismo , Escherichia coli/patogenicidad , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/patología , Infecciones por Escherichia coli/veterinaria , Vectores Genéticos , Genotipo , Porcinos , DesteteRESUMEN
Yield losses caused by lodging in barley can be partially controlled by reducing plant height. In order to understand dwarfing mechanisms and efficiently use new dwarf germplasms for a breeding program, it is important to identify QTL of plant height components. QTL analysis was performed for seven plant height component traits using a DH population of 122 lines derived from the cross of Huaai 11 x Huadamai 6. Composite interval mapping procedures detected 20 QTL, which were mapped onto chromosomes 2H, 3H, 5H, 6H, and 7H. Eleven QTL were detected in 3 years and four QTL were detected in 2 years. QTL controlling all seven plant height component traits were found near the dwarfing gene btwd1 on chromosome 7H. These QTL accounted for 27.19 to 59.73% of phenotypic variation in seven plant height component traits. Positive transgressive segregation was found for all traits. Some of the QTL identified in this study will be useful for understanding the dwarfing mechanism and for developing new dwarf varieties using marker-assisted selection.
Asunto(s)
Haploidia , Hordeum/genética , Fenotipo , Sitios de Carácter Cuantitativo/genética , Cruzamiento , Genética de Población , Hordeum/crecimiento & desarrolloRESUMEN
The transporter associated with antigen processing (TAP) transports peptides from the cytosol into the endoplasmic reticulum for subsequent loading onto the major histocompatibility complex (MHC) class I molecules. This study showed the dynamic changes in the TAP1 expression level in newborn to weaning piglets. Tissue expression profiles revealed that the TAP1 gene was expressed at low levels in all tissues, and the expression levels were relatively higher in the lung, spleen, lymph, and thymus; further, no significant difference was observed in the expression in each tissue among the 3 unweaned stages (8, 18, and 30 days). Nevertheless, the postweaning (35 days) expression levels in tissues, including the spleen, lung, lymph, duodenum, and jejunum were significantly higher than those in the unweaned stages. Furthermore, gene ontology and pathway analysis showed that TAP1 took part in 38 biological functions and 5 pathway processes, including ABC transporters and antigen processing and presentation. These analyses showed that the TAP1 gene, which was related to MHC I immune regulation, had a stable and low expression level in unweaned stages; however, its expression increased in the postweaning stages. The high expression level of TAP1 indicated that the gene might play an important role in Escherichia coli F18 resistance.
Asunto(s)
Transportadoras de Casetes de Unión a ATP/biosíntesis , Porcinos/genética , Transportador de Casetes de Unión a ATP, Subfamilia B, Miembro 2 , Transportadoras de Casetes de Unión a ATP/genética , Animales , Escherichia coli/patogenicidad , Regulación del Desarrollo de la Expresión Génica , Antígenos de Histocompatibilidad Clase I/biosíntesis , Porcinos/crecimiento & desarrollo , Porcinos/microbiología , Distribución Tisular , DesteteRESUMEN
Recent genome wide association studies (GWAS) and candidate gene studies have revealed many novel loci associated with colorectal cancer susceptibility. We evaluated the effect of these colorectal cancer-associated variants on the risk of breast cancer in a Chinese Han population. Seven single nucleotide polymorphisms (SNPs) (rs3856806 in PPARG, rs7014346 in POU5F1P1, rs989902 in PTPN13, rs1801278 in IRS1, rs7003146 in TCF7L2, rs1503185 in PTPRJ, and rs63750447 in MLH1) were genotyped in Han Chinese subjects, including 216 patients with breast cancer and 216 matched controls, using the Sequenom MassARRAY platform. The association of genotypes with susceptibility to breast cancer was analyzed using the odds ratio (OR), with 95% confidence interval (CI) and logistic regression. Three SNPs (rs7014346, rs989902, and rs7003146) were found to be significantly associated with the susceptibility of breast cancer. The GA and AA genotypes of rs7003146 in TCF7L2, and the CA and CC genotype of rs989902 in PTPN13 were associated with reduced breast cancer risk in the Chinese Han population based on the best-fit dominant model. The GG genotype of rs7014346 in POU5F1P1 was also significantly associated with decreased breast cancer risk under the best-fit additive model. Our results confirmed the association of rs7014346 in POU5F1P1, rs989902 in PTPN13, and rs7003146 in TCF7L2 with variations in the risk of breast cancer in a Chinese Han population.
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Neoplasias de la Mama/genética , Neoplasias Colorrectales/genética , Proteínas de Homeodominio/genética , Polimorfismo de Nucleótido Simple , Proteína Tirosina Fosfatasa no Receptora Tipo 13/genética , Proteína 2 Similar al Factor de Transcripción 7/genética , Pueblo Asiatico , Estudios de Casos y Controles , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Persona de Mediana Edad , RiesgoRESUMEN
Conventional genomic DNA extraction protocols need expensive and hazardous reagents for decontamination of phenolic compounds from the extracts and are only suited for certain types of tissue. We developed a simple, time-saving and cost-efficient method for genomic DNA extraction from various types of organisms, using relatively innocuous reagents. The protocol employs a single purification step to remove contaminating compounds, using a silica column and a non-hazardous buffer, and a chaotropic-detergent lysing solution that hydrolyzes RNA and allows the selective precipitation of DNA from cell lysates. We used this system to extract genomic DNA from different tissues of various organisms, including algae (Dunaliella salina), human peripheral blood, mouse liver, Escherichia coli, and Chinese hamster ovary cells. Mean DNA yields were 20-30 µg/cm(3) from fresh tissues (comparable to yields given by commercial extraction kits), and the 260/280 nm absorbance ratio was 1.8-2.0, demonstrating a good degree of purity. The extracted DNA was successfully used in PCR, restriction enzyme digestion and for recombinant selection studies.
Asunto(s)
ADN/aislamiento & purificación , Genoma , Reacción en Cadena de la Polimerasa/métodos , Animales , Células CHO , Chlorophyta/química , Cricetinae , Cricetulus , Escherichia coli/química , Humanos , Ratones , Ratones Endogámicos BALB CRESUMEN
Many fundamental questions are still unanswered regarding the very existence of precursor states and the microscopic mechanism of its population in the case of dissociative adsorption of light molecules on metal surfaces. We report results of classical trajectory calculations for H(2)/Pd(110) based on a six-dimensional potential energy surface obtained from ab initio calculations and a generalized Langevin oscillator model to account for energy exchange with the surface and dissipation. A quantitative characterization of the dynamic process is obtained which elucidates the respective roles played by direct dissociation, dynamic trapping, and precursor mediated adsorption. We predict the existence of H2 molecular chemisorption and provide the precise adsorption conditions for its experimental observation.