soil organic carbon has been the most important soil quality measurement factors and has intense relation with soil physical, chemical and biological characteristics. organic matter and its components are important factors of soil aggregates constitution and stability and play significant role in its structure.so, this research has been done for achieving this purpose. this area is arounding sa...

objective: soil organic carbon has been the most important soil quality measurement factors and has intense relation with soil physical, chemical and biological characteristics. organic matter and its components are important factors of soil aggregates constitution and stability and play significant role in its structure. so, this research has been done for achieving this purpose. methods: this...

Ciliated protozoa have two functionally distinct nuclei, a micronucleus (MIC) and a macronucleus (MAC) [1]. These two nuclei are distinct in size, transcriptional activity, and division cycle control, proceeding with cycles of DNA replication and nuclear division at different times within the same cell [2, 3]. The structural basis generating functionally distinct nuclei remains unknown. Here, w...

The organization of the 5s rRNA genes in the MACronuclear genome of Tetrahymena thermophila was examined during MAC development and replication. The 5s genes are arranged in several tandem arrays of alternating transcribed and spacer sequences in both MICronucleus and MAC. The number of EcoRI fragments bearing 5s gene clusters is similar in MIC and MAC. Most fragments occur in both the MIC and ...

Organisms of the Mycobacterium avium complex (MAC) cause disseminated disease in patients with AIDS, and evidence points to the gastrointestinal tract as the major route of infection. Since MAC can bind to and invade intestinal mucosal cells, we examined whether subinhibitory concentrations of antibiotics which have anti-MAC activity in vitro affect the interaction between MAC and HT-29 intesti...

DNA is eliminated during development of the somatic MACronucleus from the germinal MICronucleus in the ciliated protozoan, Tetrahymena thermophila. Facultatively persistent sequences are a class of sequences that persist in the MAC DNA of some cell lines but are eliminated from the MAC DNA of other cell lines. One cloned MAC fragment contains a persistent sequence as well as sequences normally ...

Genetically programmed DNA rearrangements can regulate mRNA expression at an individual locus or, for some organisms, on a genome-wide scale. Ciliates rely on a remarkable process of whole-genome remodeling by DNA elimination to differentiate an expressed macronucleus (MAC) from a copy of the germline micronucleus (MIC) in each cycle of sexual reproduction. Here we describe results from the fir...

The ciliate protozoan Tetrahymena thermophila contains two types of structurally and functionally differentiated nuclei: the transcriptionally active somatic macronucleus (MAC) and the transcriptionally silent germ-line micronucleus (MIC). Here, we demonstrate that MAC features well-positioned nucleosomes downstream of transcription start sites and flanking splice sites. Transcription-associate...

Metastasis and growth in neoplastic lesions requires the multistep regulation of microenvironmental factors. We aimed to elucidate the microenvironmental changes in the process of lymphatic metastasis of lung squamous cell carcinoma. We examined the morphological characteristics of 102 cases of primary tumor (PT), 50 of intralymphatic tumor (ILT), 51 of lymph node (LN) micrometastasis (LN-Mic; ...

The nuclear pore complex (NPC), a gateway for nucleocytoplasmic trafficking, is composed of ∼30 different proteins called nucleoporins. It remains unknown whether the NPCs within a species are homogeneous or vary depending on the cell type or physiological condition. Here, we present evidence for compositionally distinct NPCs that form within a single cell in a binucleated ciliate. In Tetrahyme...