Efficacy of nutritional supplement (Haras) on carbon monoxide levels in smokers and non-smokers: An observational study.

Context: Carbon monoxide (CO) concentrations in exhaled air may impart a quick, non-invasive method to determine smoking status. Haras is a nutraceutical medication, which is slowly gaining recognition for its antioxidant and anti-inflammatory activities.

Aims: The effectiveness of the Haras therapy in smokers and non-smokers will be assessed by evaluating breath CO levels.

Tetraploidy-linked sensitization to CENP-E inhibition in human cells.

Tetraploidy is a hallmark of cancer cells, and tetraploidy-selective cell growth suppression is a potential strategy for targeted cancer therapy. However, how tetraploid cells differ from normal diploids in their sensitivity to anti-proliferative treatments remains largely unknown. In this study, we found that tetraploid cells are significantly more susceptible to inhibitors of a mitotic kinesin (CENP-E) than are diploids.

Ewing's sarcoma of the mandible with multilocular radiolucency.

Ewing's sarcoma (ES) is a small blue round cell tumor, malignant in nature typically affecting long bones and pelvis. Occurrence of ES in the head and neck region is rare and is reported to be 2%-3%, of which the chances of having primary lesion are rare. In the head and neck region, it has been reported to strike skull, supraclavicular region, parotid region, orbital floor, nasal cavity, maxilla, mandible and zygoma.

Histopathologic and immunohistochemical findings of odontogenic jaw cysts treated by decompression technique.

Context: Odontogenic cysts are among the most common lesions to affect the oral and maxillofacial region. Cysts are capable of causing significant bony disfigurement, tooth displacement and pathological fractures. Several surgical approaches exist for the management of larger cysts of the jaws.

Molecular basis of functional exchangeability between ezrin and other actin-membrane associated proteins during cytokinesis.

The mechanism that mediates the interaction between the contractile ring and the plasma membrane during cytokinesis remains elusive. We previously found that ERM (Ezrin/Radixin/Moesin) proteins, which usually mediate cellular pole contraction, become over-accumulated at the cell equator and support furrow ingression upon the loss of other actin-membrane associated proteins, anillin and supervillin. In this study, we addressed the molecular basis of the exchangeability between ezrin and other actin-membrane associated proteins in mediating cortical contraction during cytokinesis.

The Current Understanding on Langerhans' Cells and Its Role in Oral Lesions.

Objective: Description of Langerhans' cells (LCs) as an important antigen-presenting cells responsible for detecting the antigens, recruiting T-cells, and thereby initiating the immune response. An adequate response of the mucosal immune system is essential to protect the mucosa against pathological conditions. Hence, a detailed review was planned about this unique antigen-presenting cell.

Structure, function and role of CD44 in neoplasia.

CD44 is a group of protein molecules which perform a variety of functions. Their wide range of functions are mainly based on their multiple variations in their molecular structure. Furthermore, they are distributed in various tissues of the human body.

Allosteric Regulation of Cyclin-B Binding by the Charge State of Catalytic Lysine in CDK1 Is Essential for Cell-Cycle Progression.

Cyclin-dependent kinase 1 (CDK1) is essential for cell-cycle progression. While dependence of CDK activity on cyclin levels is well established, molecular mechanisms that regulate their binding are less understood. Here, we report for the first time that CDK1:cyclin-B binding is not default but rather determined by the evolutionarily conserved catalytic residue, lysine-33 in CDK1.

A rare case report of craniofacial fibrous dysplasia.

Fibrous dysplasia (FD) is a fibro-osseous lesion of the osseous structures of the body. The exact cause is unknown; however, recently, the cause has been reported to be postzygomatic somatic mutation in guanine nucleotide-binding protein, alpha stimulating 1 gene located at chromosome 20q13.2.

Coarse-grained simulations of actomyosin rings point to a nodeless model involving both unipolar and bipolar myosins.

Cytokinesis in many eukaryotic cells is orchestrated by a contractile actomyosin ring. While many of the proteins involved are known, the mechanism of constriction remains unclear. Informed by the existing literature and new three-dimensional (3D) molecular details from electron cryotomography, here we develop 3D coarse-grained models of actin filaments, unipolar and bipolar myosins, actin cross-linkers, and membranes and simulate their interactions.

Structure of the fission yeast actomyosin ring during constriction.

Cell division in many eukaryotes is driven by a ring containing actin and myosin. While much is known about the main proteins involved, the precise arrangement of actin filaments within the contractile machinery, and how force is transmitted to the membrane, remains unclear. Here we use cryosectioning and cryofocused ion beam milling to gain access to cryopreserved actomyosin rings in for direct 3D imaging by electron cryotomography.

Motor Activity Dependent and Independent Functions of Myosin II Contribute to Actomyosin Ring Assembly and Contraction in Schizosaccharomyces pombe.

Cytokinesis depends on a contractile actomyosin ring in many eukaryotes [1-3]. Myosin II is a key component of the actomyosin ring, although whether it functions as a motor or as an actin cross-linker to exert its essential role is disputed [1, 4, 5]. In Schizosaccharomyces pombe, the myo2-E1 mutation affects the upper 50 kDa sub-domain of the myosin II heavy chain, and cells carrying this lethal mutation are defective in actomyosin ring assembly at the non-permissive temperature [6, 7].

Isolation of Cytokinetic Actomyosin Rings from Saccharomyces cerevisiae and Schizosaccharomyces pombe.

Cytokinesis is the final stage of cell division, through which cellular constituents of mother cells are partitioned into two daughter cells resulting in the increase in cell number. In animal and fungal cells cytokinesis is mediated by an actomyosin contractile ring, which is attached to the overlying cell membrane. Contraction of this ring after chromosome segregation physically severs the mother cell into two daughters.

Immunomorphological patterns of cervical lymph nodes in oral squamous cell carcinoma.

Context: Squamous cell carcinoma (SCC) comprises 80% of the cancers of the oral cavity. Metastases to the cervical lymph nodes affects prognosis. Studying lymph node reactivity may help to understand host immune reaction against the tumor and thus influence prognosis.

Ameloblastoma: Cytopathologic profile of 12 cases and literature review.

Background: Fine-needle aspiration cytology (FNAC) has been used as a diagnostic tool in evaluating suspected lesions. It shows a high diagnostic accuracy for diagnosing salivary gland lesions.

Aim: The aim of this study was to highlight FNAC as an effective diagnostic tool in the presumptive diagnosis of ameloblastoma.

The yeast actin cytoskeleton.

The actin cytoskeleton is a complex network of dynamic polymers, which plays an important role in various fundamental cellular processes, including maintenance of cell shape, polarity, cell division, cell migration, endocytosis, vesicular trafficking, and mechanosensation. Precise spatiotemporal assembly and disassembly of actin structures is regulated by the coordinated activity of about 100 highly conserved accessory proteins, which nucleate, elongate, cross-link, and sever actin filaments. Both in vivo studies in a wide range of organisms from yeast to metazoans and in vitro studies of purified proteins have helped shape the current understanding of actin dynamics and function.

An immunohistochemical study of basement membrane heparan sulfate proteoglycan (perlecan) in oral epithelial dysplasia and squamous cell carcinoma.

Background: Basement membrane heparan sulfate proteoglycan (perlecan) has been demonstrated in precancer lesions and carcinomas of oral cavity. It helps in malignant transformation of epithelial cells. The aim of our study was to understand the immuno-localization of perlecan in oral dysplastic epithelium and oral carcinomas.

In vitro contraction of cytokinetic ring depends on myosin II but not on actin dynamics.

Cytokinesis in many eukaryotes involves the contraction of an actomyosin-based contractile ring. However, the detailed mechanism of contractile ring contraction is not fully understood. Here, we establish an experimental system to study contraction of the ring to completion in vitro.

Cylindrical cellular geometry ensures fidelity of division site placement in fission yeast.

Successful cytokinesis requires proper assembly of the contractile actomyosin ring, its stable positioning on the cell surface and proper constriction. Over the years, many of the key molecular components and regulators of the assembly and positioning of the actomyosin ring have been elucidated. Here we show that cell geometry and mechanics play a crucial role in the stable positioning and uniform constriction of the contractile ring.

Perlecan (basement membrane heparan sulfate proteoglycan) and its role in oral malignancies: an overview.

Perlecan means pearl-like structures. Perlecan is a large proteoglycan (400-500 kDa) present in virtually all vascularized tissues with a distribution that is primarily confined to basement membranes including those of oral mucosa. It is a basement membrane-type heparan sulfate proteoglycan.

The SET domain protein, Set3p, promotes the reliable execution of cytokinesis in Schizosaccharomyces pombe.

In response to perturbation of the cell division machinery fission yeast cells activate regulatory networks that ensure the faithful completion of cytokinesis. For instance, when cells are treated with drugs that impede constriction of the actomyosin ring (low doses of Latrunculin A, for example) these networks ensure that cytokinesis is complete before progression into the subsequent mitosis. Here, we identify three previously uncharacterized genes, hif2, set3, and snt1, whose deletion results in hyper-sensitivity to LatA treatment and in increased rates of cytokinesis failure.

Bacillus anthracis tubulin-related protein Ba-TubZ assembles force-generating polymers.

Pathogenicity of Bacillus anthracis depends on the faithful inheritance of plasmid pXO1, in a process that requires the plasmid encoded tubulin-related protein Ba-TubZ. Here we show, using heterologous expression in Schizosaccharomyces pombe, that Ba-TubZ assembles into a dynamic polymer in the absence of other B. anthracis proteins and can generate force capable of deforming the fission yeast nuclear envelope.

IQGAP-related Rng2p organizes cortical nodes and ensures position of cell division in fission yeast.

Correct positioning of the cell division machinery is crucial for genomic stability and cell fate determination. The fission yeast Schizosaccharomyces pombe, like animal cells, divides using an actomyosin ring and is an attractive model to study eukaryotic cytokinesis. In S.

Cell polarization: it's all about being in shape.

In eukaryotic cells microtubules and actin filaments help to generate the spatial organization of the cytoplasm that is required for polarity and shape. Recent work in fission yeast demonstrates that changing cell shape in turn reorganizes the cytoskeleton and cell polarization machinery.

The bacterial cell division protein FtsZ assembles into cytoplasmic rings in fission yeast.

During cytokinesis, most bacteria assemble a ring-like structure that is composed of the tubulin homolog FtsZ. The mechanisms regulating assembly and organization of FtsZ molecules into rings are not fully understood. Here, we express bacterial FtsZ in the fission yeast Schizosaccharomyces pombe and find that FtsZ filaments assemble into cytoplasmic rings.