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51.
Mortality incidence estimation using federal death certificate and natality data with an application to Tay–Sachs disease
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For confidentiality reasons, US federal death certificate data are incomplete with regards to the dates of birth and death for the decedents, making calculation of total lifetime of a decedent impossible and thus estimation of mortality incidence difficult. This paper proposes the use of natality data and an imputation‐based method to estimate age‐specific mortality incidence rates in the face of this missing information. By utilizing previously determined probabilities of birth, a birth date and death date are imputed for every decedent in the dataset. Thus, the birth cohort of each individual is imputed, and the total on‐study time can be calculated. This idea is implemented in two approaches for estimation of mortality incidence rates. The first is an extension of a person‐time approach, while the second is an extension of a life table approach. Monte Carlo simulations showed that both approaches perform well in comparison to the ideal complete data methods, but that the person‐time method is preferred. An application to Tay–Sachs disease is demonstrated. It is concluded that the imputation methods proposed provide valid estimates of the incidence of death from death certificate data without the need for additional assumptions under which usual mortality rates provide valid estimates. 相似文献
52.
Mixtures of toluene, ethylbenzene, and the xylenes spiked with 14C-labeled toluene or m-xylene were added to bench-scale bioventing simulation columns filled with hydrocarbon-contaminated subsurface soils. After 2 to 4 weeks of incubation during which air was pumped through the column at rates of at least 2?ml·min?1·kg?1 between 54 and 84% of the radiolabel was recovered in traps as outgassed parent compound from four columns sterilized with gamma-irradiation. In contrast, seven nonsterilized but otherwise identically treated (except for inorganic nitrogen addition) columns lost less than 0.4% (and one column lost 0.7%) of the radiolabel through outgassing of the parent compound. Nonsterilized columns lost 40 to 61% of the radiolabel as 14CO2, whereas gamma-irradiated columns usually lost only trace amounts of 14C in this form. Biologically active columns also retained much larger fractions than sterilized columns of the radiolabel in the subsoil in forms, possibly microbial biomass, from which it could be recovered by wet oxidation. Addition of 10 or 40?mg/kg of mineral nitrogen had no consistent effect on bioventing performance. 相似文献
53.
Parvaneh Naserzadeh Seyed Alireza Mortazavi Khadijeh Ashtari Ahmad Salimi Mehdi Farokhi Jalal Pourahmad 《Journal of biochemical and molecular toxicology》2018,32(6)
Silk fibroin nanoparticles (SFNPs) as a natural polymer have been utilized in biomedical applications such as suture, tissue engineering‐based scaffolds, and drug delivery carriers. Since there is little data regarding the toxicity effects on different cells and tissues, we aimed to determine the toxicity mechanisms of SFNPs on human lymphocytes and monocytes based on reliable methods. Our results showed that SFNPs (0.5, 1, and 2 mg/mL) induced oxidative stress via increasing reactive oxygen species production, mitochondrial membrane potential (?Ψ) collapse, which was correlated to cytochrome c release and Adenosine diphosphate (ADP)/Adenosine tri phosphate (ATP) ratio increase as well as lysosomal as another toxicity mechanism, which led to cytosolic release of lysosomal digestive proteases, phosphor lipases, and apoptosis signaling. Taken together, these data suggested that SFNPs toxicity was associated with mutual mitochondrial/lysosomal cross‐talk and oxidative stress on human lymphocytes and monocytes with activated apoptosis signaling. 相似文献
54.
Spectral karyotyping refines cytogenetic diagnostics of constitutional chromosomal abnormalities 总被引:12,自引:0,他引:12
E. Schröck T. Veldman Hesed Padilla-Nash Y. Ning Jack Spurbeck Syed Jalal Lisa G. Shaffer Peter Papenhausen Chahira Kozma Mary C. Phelan Eigil Kjeldsen Stephen A. Schonberg Patricia O’Brien Les Biesecker Stan du Manoir Thomas Ried 《Human genetics》1997,101(3):255-262
Karyotype analysis by chromosome banding is the standard method for identifying numerical and structural chromosomal aberrations
in pre- and postnatal cytogenetics laboratories. However, the chromosomal origins of markers, subtle translocations, or complex
chromosomal rearrangements are often difficult to identify with certainty. We have developed a novel karyotyping technique,
termed spectral karyotyping (SKY), which is based on the simultaneous hybridization of 24 chromosome-specific painting probes
labeled with different fluorochromes or fluorochrome combinations. The measurement of defined emission spectra by means of
interferometer-based spectral imaging allows for the definitive discernment of all human chromosomes in different colors.
Here, we report the comprehensive karyotype analysis of 16 samples from different cytogenetic laboratories by merging conventional
cytogenetic methodology and spectral karyotyping. This approach could become a powerful tool for the cytogeneticists, because
it results in a considerable improvement of karyotype analysis by identifying chromosomal aberrations not previously detected
by G-banding alone. Advantages, limitations, and future directions of spectral karyotyping are discussed.
Received: 4 August 1997 / Accepted: 8 September 1997 相似文献
55.
Zi-xiang Chen Qiong Lei Rui-lin He Zhong-feng Zhang Ahmed Jalal Khan Chowdhury 《Saudi Journal of Biological Sciences》2016,23(1):S142-S147
In this review, the characteristics and applications of structural laminated veneer lumber made from planted forest wood is introduced, and its preparation is explained, including various tree species and slab qualities, treatments for multiple effects and reinforced composites. The relevant factors in the bonding technology and pressing processes as well as the mechanical properties, research direction and application prospects of structural laminated veneer lumber made from planted forest wood are discussed. 相似文献
56.
Sylvie Rocheleau Ruxandra Cimpoia Louise Paquet Iris van Koppen Serge R. Guiot Jalal Hawari Guy Ampleman Sonia Thiboutot Geoffrey I. Sunahara 《Bioremediation Journal》1999,3(3):233-246
The ecotoxicological effects of four bioslurry reactors treating 2,4,6-trinitotoluene (TNT)- and 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX)-spiked soil were evaluated. A control bioslurry reactor was used to assess the endogenous toxicity of the bioslurry operation conditions. A battery of ecotoxicity tests was used: Microtox, green algae growth inhibition, bacterial genotoxicity and mutagenicity, and earthworm mortality and growth inhibition. Bioslurry soluble and solid phases were separated by centrifugation in order to identify toxicity and possible toxicants associated with each phase. Microtox toxicity values were initially very high in both bioslurry reactors spiked with TNT, in relation with TNT concentration. Initial toxicity was also detected by algal growth inhibition, earthworm lethality, genotoxicity and mutagenicity tests. An endogenous toxicity was detected in the control bioreactor using the Microtox and the SOS Chromotest. The soluble phase of the control bioslurry was genotoxic, suggesting that some potentially genotoxic agents were induced in the bioslurry samples. At the end of the bioremediation treatment, data showed that toxicity was reduced using all of the bioassays, except for earthworm lethality and growth inhibition tests in both RDX-spiked bioslurries. This study demonstrates the usefulness of a battery of toxicity tests to monitor bioremediation processes. 相似文献
57.
Biotransformation of 2,4,6-Trinitrotoluene with Phanerochaete chrysosporium in Agitated Cultures at pH 4.5
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Jalal Hawari Annamaria Halasz Sylvie Beaudet Louise Paquet Guy Ampleman Sonia Thiboutot 《Applied microbiology》1999,65(7):2977-2986
The biotransformation of 2,4,6-trinitrotoluene (TNT) (175 μM) by Phanerochaete chrysosporium with molasses and citric acid at pH 4.5 was studied. In less than 2 weeks, TNT disappeared completely, but mineralization (liberated 14CO2) did not exceed 1%. A time study revealed the presence of several intermediates, marked by the initial formation of two monohydroxylaminodinitrotoluenes (2- and 4-HADNT) followed by their successive transformation to several other products, including monoaminodinitrotoluenes (ADNT). A group of nine acylated intermediates were also detected. They included 2-N-acetylamido-4,6-dinitrotoluene and its p isomer, 2-formylamido-4,6-dinitrotoluene and its p isomer (as acylated ADNT), 4-N-acetylamino-2-amino-6-nitrotoluene and 4-N-formylamido-2-amino-6-nitrotoluene (as acetylated DANT), 4-N-acetylhydroxy-2,6-dinitrotoluene and 4-N-acetoxy-2,6-dinitrotoluene (as acetylated HADNT), and finally 4-N-acetylamido-2-hydroxylamino-6-nitrotoluene. Furthermore, a fraction of HADNTs were found to rearrange to their corresponding phenolamines (Bamberger rearrangement), while another group dimerized to azoxytoluenes which in turn transformed to azo compounds and eventually to the corresponding hydrazo derivatives. After 30 days, all of these metabolites, except traces of 4-ADNT and the hydrazo derivatives, disappeared, but mineralization did not exceed 10% even after the incubation period was increased to 120 days. The biotransformation of TNT was accompanied by the appearance of manganese peroxidase (MnP) and lignin-dependent peroxidase (LiP) activities. MnP activity was observed almost immediately after TNT disappearance, which was the period marked by the appearance of the initial metabolites (HADNT and ADNT), whereas the LiP activity was observed after 8 days of incubation, corresponding to the appearance of the acyl derivatives. Both MnP and LiP activities reached their maximum levels (100 and 10 U/liter, respectively) within 10 to 15 days after inoculation. 相似文献
58.
59.
Fan Yang Jalal Jalali Sendi R. C. Johns Makio Takeda 《Applied Entomology and Zoology》2017,52(3):401-406
Hyphantria cunea (Drury) has colonized many countries outside its native range of North America and has become a model species for studies of the colonization and subsequent adaptation of agricultural pests. Molecular genetic analyses can clarify the origin and subsequent adaptations to non-native habitats. Using the mitochondrial COI gene, we examined the genetic relationships between invasive populations (China, Iran, Japan, and Korea) and native populations (i.e., the United States). The Jilin (China) and Guilan (Iran) populations showed nine previously unknown haplotypes that differed from those found in the south–central United States, suggesting multiple colonization events and different regions of invasion. A dominant mtDNA haplotype in populations in the United States was shared by all of the populations investigated, suggesting that H. cunea with that haplotype have successfully colonized China, Iran, Japan, and Korea. 相似文献
60.
Jalal Jalilian Azin Najafabadi Mohammad Reza Zardashti 《Journal of Plant Interactions》2017,12(1):92-99
This factorial field experiment was done based on a randomized complete block design in Urmia University, Iran, in 2013 and was repeated in 2014. Treatments included two farming systems (high input and organic) and different intercropping patterns that alternated bitter vetch (Vicia ervilia L.) and safflower (Carthamus tinctorius L.) with row ratios of 2:2, 3:2, 4:2 and 5:2. Sole cropping of bitter vetch and safflower was used as the control. In both years, the 2:2 intercropping pattern had biomass yield advantages compared to sole cropping and the other intercropping ratios, based on greater land equivalent ratio values. Safflower had higher relative crowding coef?cients, competitive ratio (CR) and aggressivity (A) values than bitter vetch. High-input farming was more effective than the organic system in both years. Safflower was the superior competitor when grown with bitter vetch, and its productivity dominated the total biomass yields. Thus, intercropping of safflower with bitter vetch has the potential to improve performance with high land-use efficiency. 相似文献