London Resin (LR) White is a commonly used resin for embedding specimens to be used for immuno- and/or cytochemical studies. In some instances, due to either the properties of the specimen or the availability of various reagents and equipment, it becomes necessary and/or more convenient to polymerize LR White using ...

Individual dynamic microtubules can generate pushing or pulling forces when their growing or shrinking ends are in contact with cellular objects such as the cortex or chromosomes. These microtubules can operate in parallel bundles, for example when interacting with mitotic chromosomes. Here, we investigate the force-generating capabilities of a bundle ...

Almost all studies of the densest particle packings consider convex particles. Here, we provide exact constructions for the densest known two-dimensional packings of superdisks whose shapes are defined by |x{1}|{2p}+|x{2}|{2p}<or=1 and thus contain a large family of both convex (p>or=0.5) and concave (0<p<0.5) particles. Our candidate maximal packing arrangements are ...

The spindle assembly checkpoint (SAC) prevents anaphase onset until all chromosomes accomplish proper bipolar attachments to the mitotic spindle and come under tension, thereby ensuring the fidelity of chromosome segregation. Despite significant advances in our understanding of SAC signalling, a clear link between checkpoint signalling and the molecular mechanisms underlying ...

The Ndc80 complex is a core component of the kinetochore, which links chromosomes to microtubules. Recently, Ciferri et al. (2008) published an atomic-level structure of the complex with implications for kinetochore architecture and for the generation and control of chromosome movements during mitosis.

The centromere is the region of the chromosome where the kinetochore forms. Kinetochores are the attachment sites for spindle microtubules that separate duplicated chromosomes in mitosis and meiosis. Kinetochore formation depends on a special chromatin structure containing the histone H3 variant CENP-A. The epigenetic mechanisms that maintain CENP-A chromatin throughout ...

During the past 12000 years agricultural systems have transitioned from natural habitats to conventional agricultural regions and recently to large areas of genetically engineered (GE) croplands. This GE revolution occurred for cotton in a span of slightly more than a decade during which a switch occurred in major cotton production ...

Recent studies suggest that the human Kinesin-8 molecular motor Kif18A has a role in chromosome congression. Specifically, these studies find that Kif18A promotes chromosome congression by attenuating chromosome oscillation magnitudes. Together with recent modeling work, in vitro studies, and the analysis of in vivo yeast data, these reports reveal how ...

Accurate chromosome segregation in mitosis is crucial to maintain a diploid chromosome number. A majority of cancer cells are aneuploid and chromosomally unstable, i.e. they tend to gain and lose chromosomes at each mitotic division. Chromosome mis-segregation can arise when cells progress through mitosis with mis-attached kinetochores. Merotelic kinetochore orientation, ...

The mechanisms to explain atrial fibrillation (AF) have been widely debated. Although contemporary experimental techniques have provided more insight, hypotheses regarding AF propagation conceived in the early half of the century remain minimally altered and relevant today. Modern mapping technologies have implicated multiwavelet reentry as the electrophysiologic basis to explain ...

Nestlings of many avian brood parasites are virtuosos at mimicking host nestling vocalizations, which, like egg mimicry, presumably ensures acceptance by host parents. Having been accepted, parasitic nestlings then often exaggerate the aspects of the host's display to increase parental care. Host nestlings may, in turn, exaggerate their vocalizations to ...

White-rot fungus Trameteshirsute (T.h. 19-6) was used for modifying the eucalyptus CTMP fibres. Results show that the T.h. 19-6 removed mainly lignin (by 7.42%) and extractive (by 11.52%) after a short period of 5days incubation. Due to the fungal degradation of the fibre wall materials, the middle lamella remainder on ...

Chromosome segregation in mitosis is orchestrated by dynamic interaction between spindle microtubules and the kinetochore. Septin (SEPT) belongs to a conserved family of polymerizing GTPases localized to the metaphase spindle during mitosis. Previous study showed that SEPT2 depletion results in chromosome mis-segregation correlated with a loss of centromere-associated protein E ...

Mitotic chromosomes segregate at the ends of shortening spindle microtubules (MTs). In budding yeast, the Dam1 multiprotein complex supports this dynamic attachment, thereby contributing to accurate chromosome segregation. Purified Dam1 will track the end of a depolymerizing MT and can couple it to microbead transport in vitro. The processivity of ...

STUDY DESIGN: Biomechanical study. OBJECTIVE: To test 2 different intervertebral positions of a semilunar cage and their effects on 3-dimensional stability and segmental lordosis in a model of transforaminal lumbar interbody fusion (TLIF). SUMMARY OF BACKGROUND DATA: In his original TLIF description, Harms recommended decortication of endplates, followed by placement ...

The mitotic kinesin centromere protein E (CENP-E) is an essential kinetochore component that directly contributes to the capture and stabilization of spindle microtubules by kinetochores. Although reduction in CENP-E leads to high rates of whole chromosome missegregation, neither its properties as a microtubule-dependent motor nor how it contributes to the ...

The centromere is a specialised region of the eukaryotic chromosome that directs the equal segregation of sister chromatids into two daughter cells during mitosis. In mitosis, the kinetochores mediate (1) microtubule capture and chromosome alignment at a metaphase plate; (2) the correction of improper microtubule attachments; (3) the maintenance of ...

In vivo studies suggest that centromeric protein E (CENP-E), a kinesin-7 family member, plays a key role in the movement of chromosomes toward the metaphase plate during mitosis. How CENP-E accomplishes this crucial task, however, is not clear. Here we present single-molecule measurements of CENP-E that demonstrate that this motor ...

The cell morphology, gene expression, and matrix synthesis of articular chondrocytes are known to vary with depth from the tissue surface. The objective of this study was to investigate if chondrocytes from different zones respond to in vitro oscillatory tensile loading in distinct ways and whether tensile strain, which is ...

The chromosome theory of heredity, developed in 1902-1904, became one of the foundation stones of twentieth-century genetics. It is usually referred to as the Sutton-Boveri theory after Walter Sutton and Theodor Boveri. However, the contributions of Theodor Boveri and his co-worker, Marcella O'Grady Boveri (also his wife), to the understanding ...

Silks have been proposed as potential scaffold materials for tissue engineering, mainly because of their physical properties. They are stable at physiological temperatures, flexible and resist tensile and compressive forces. Bombyx mori (silkworm) cocoon silk has been used as a suture material for over a century, and has proved to ...

OBJECTIVE: To test the null hypothesis that there is no difference between premolar position visualized on panoramic radiographs (PRs) and lateral headfilms (LHs). MATERIALS AND METHODS: The prevalence of differences in the direction of crown angulation between PR and LH was assessed. Furthermore, brass wire markers with different sagittal and ...

Loss or gain of whole chromosome, the form of chromosome instability commonly associated with cancers is thought to arise from aberrant chromosome segregation during cell division. Chromosome segregation in mitosis is orchestrated by the interaction of kinetochores with spindle microtubules. Our studies show that NEK2A is a kinetochore-associated protein kinase ...

The mitotic checkpoint is an essential surveillance mechanism that ensures high fidelity chromosome segregation during mitosis. Mitotic checkpoint function depends on numerous kinetochore proteins, including ZW10, ROD, and Zwilch (the ROD-ZW10-Zwilch complex). Through an extensive mutagenesis screen of hZW10, we have mapped the kinetochore localization domain of hZW10 as well ...

The Dam1/DASH outer kinetochore complex is required for high-fidelity chromosome segregation in budding and fission yeast. Unlike budding yeast, the fission yeast complex is non-essential, however it promotes bipolar microtubule attachment in conjunction with microtubule-depolymerising kinesin-8 Klp5 and Klp6. Here, we screened for dam1 temperature sensitive mutants in a klp5 ...

A recent concept connecting the lipophilicity of organic chemicals with their genotoxicity on a chromosomal level implies that the lipophilic character of organic chemicals determines a certain background of chromosomal genotoxicity that can be addressed as "non-specific". This is opposed to compounds with more "specific" modes of action. Such mechanisms ...

In eukaryotic cells, proper formation of the spindle is necessary for successful cell division. We have studied chromosome recapture in the fission yeast Schizosaccharomyces pombe. We show by live cell analysis that lost kinetochores interact laterally with intranuclear microtubules (INMs) and that both microtubule depolymerization (end-on pulling) and minus-end-directed movement ...

During vertebrate cell division, chromosomes oscillate with periods of smooth motion interrupted by abrupt reversals in direction. These oscillations must be spatially constrained in order to align and segregate chromosomes with high fidelity, but the molecular mechanism for this activity is uncertain. We report here that the human kinesin-8 Kif18A ...

The total heat gained by the North Atlantic Ocean over the past 50 years is equivalent to a basinwide increase in the flux of heat across the ocean surface of 0.4 +/- 0.05 watts per square meter. We show, however, that this basin has not warmed uniformly: Although the tropics ...

BACKGROUND: In Saccharomyces cerevisiae, nutrient limitation stimulates diploid cells to undergo DNA replication and meiosis, followed by the formation of four haploid spores. Septins are a family of proteins that assemble a ring structure at the mother-daughter neck during vegetative growth, where they control cytokinesis. In sporulating cells, the septin ...

Menkes disease is caused by mutations in the copper-transporting P(1B)-type ATPase ATP7A. ATP7A has a dual function: it serves to incorporate copper into copper-dependent enzymes, and it maintains intracellular copper levels by removing excess copper from the cytosol. To accomplish both functions, the protein traffics between different cellular locations depending ...

The centromere is a specialized region of eukaryotic chromosomes that is essential for faithful chromosome segregation during mitosis and meiosis. A kinetochore is assembled at the centromere of each chromatid of a replicated chromosome and forms a dynamic interface with microtubules of the mitotic spindle. In recent years, many kinetochore ...

This paper reports on the development of a new lower limb prosthesis that can change its volume and hardness based on the users requirements. The size and viscosity of several Magneto-Rheological fluid filled bags, fixed on the inner side of the socket is changed, in order to vary the socket ...

Precise distalization of maxillary molars is of significant value for nonextraction treatment of Class II malocclusion associated with a normal mandible. Most of the distalizing appliances available today produce adverse effects, eg, molar tipping and rotation, incisor proclination, and lack of anchorage control during the space-consolidation phase. To address these ...

For proper chromosome segregation, the sister kinetochores must attach to microtubules extending from the opposite spindle poles. Any errors in microtubule attachment can induce aneuploidy. In this study, we identify a novel conserved Caenorhabditis elegans microtubule-associated protein, regulator of microtubule dynamics 1 (RMD-1), that localizes to spindle microtubules and spindle ...

The mitotic checkpoint ensures proper chromosome segregation by monitoring two critical events during mitosis. One is kinetochore attachment to the mitotic spindle, and the second is the alignment of chromosomes at the metaphase plate, resulting in tension across sister kinetochores (reviewed in [1, 2]). Mitotic-checkpoint proteins are known to accumulate ...

The influence of the composition and the relative humidity on the properties of pharmaceutical compacts prepared from mixtures of three excipients and three super-disintegrants was evaluated. Various amounts of super-disintegrant and different conditions of relative humidity during the storage were used to study mechanistically the disintegration process and to connect ...

Abstract-The high-power piezoelectric characteristics in h001i oriented ceramics of bismuth layer structured ferroelectrics (BLSF), SrBi(2)Nb(2)O(9) (SBN), (Bi,La)(4)Ti(3)O(12) (BLT), and CaBi(4)Ti(4)O(15) (CBT), were studied by a constant voltage driving method. These textured ceramics were fabricated by a templated grain growth (TGG) method, and their Lotgering factors were 95%, 97%, and 99%, ...

Segregation of sister chromatids to opposite spindle poles during anaphase is dependent on the prior capture of sister kinetochores by microtubules extending from opposite spindle poles (bi-orientation). If sister kinetochores attach to microtubules from the same pole (syntelic attachment), the kinetochore-spindle pole connections must be re-oriented to be converted to ...

Accurate segregation of chromosomes, essential for the stability of the genome, depends on 'bi-orientation'-simultaneous attachment of each individual chromosome to both poles of the mitotic spindle. On bi-oriented chromosomes, kinetochores (macromolecular complexes that attach the chromosome to the spindle) reside on the opposite sides of the chromosome's centromere. In contrast, ...

Chromosome segregation during mitosis requires the assembly of a large proteinaceous structure termed the kinetochore. In Caenorhabditis elegans, KNL-1 is required to target multiple outer kinetochore proteins. Here, we demonstrate that the vertebrate KNL1 counterpart is essential for chromosome segregation and is required to localize a subset of outer kinetochore ...

Mitotic centromere-associated kinesin (MCAK)/Kif2C is the most potent microtubule (MT)-destabilizing enzyme identified thus far. However, MCAK's function at the centromere has remained mechanistically elusive because of interference from cytoplasmic MCAK's global regulation of MT dynamics. In this study, we present MCAK chimeras and mutants designed to target centromere-associated MCAK for ...

Which variables determine whether a country chooses an open or protected market? It has been argued that economic downturn leads to a higher propensity for protectionism. We find for seven Latin American countries in the second half of the 20th century that declining GDP motivated the opening wave, especially during ...

Mitotic chromosome motions are driven by microtubules (MTs) and associated proteins that couple kinetochores to MT ends. A good coupler should ensure a high stability of attachment, even when the chromosome changes direction or experiences a large opposing force. The optimal coupler is also expected to be efficient in converting ...

The spindle checkpoint controls mitotic progression. Checkpoint proteins are temporally recruited to kinetochores, but their docking site is unknown. We show that a human kinetochore oncoprotein, AF15q14/blinkin, a member of the Spc105/Spc7/KNL-1 family, directly links spindle checkpoint proteins BubR1 and Bub1 to kinetochores and is required for spindle checkpoint and ...

In eukaryotic cells, proper formation of the spindle is necessary for successful cell division. For faithful segregation of sister chromatids, each sister kinetochore must attach to microtubules that extend to opposite poles (chromosome bi-orientation). At the metaphase-anaphase transition, cohesion between sister chromatids is removed, and each sister chromatid is pulled ...

Precise chromosome segregation during cell division results from the attachment of chromosomes to microtubules emanating from both poles of the spindle apparatus. The molecular machinery involved in establishing and maintaining properly oriented microtubule attachments remains murky. Some clarity is now emerging with the identification of Bod1 (Biorientation Defective 1), a ...

We have combined the proteomic analysis of Xenopus laevis in vitro-assembled chromosomes with RNA interference and live cell imaging in HeLa cells to identify novel factors required for proper chromosome segregation. The first of these is Bod1, a protein conserved throughout metazoans that associates with a large macromolecular complex and ...

During mitosis, the condensed chromosomes undergo a series of spectacular oscillations after they are captured in an end-on manner by kinetochore microtubules (KMT) emanating from the spindle poles. Such oscillations are commonly attributed to tug-of-war-like mechanisms, where the mechanical force imbalance alone drives the chromosome movement. However, a large portion ...

In fission yeast centromeres cluster at the nuclear envelope in a region underlying the spindle pole body during interphase, an arrangement known as a Rabl configuration. We have identified a strain in which one pair of sister kinetochores is unclustered from the others and binds the nuclear envelope at a ...