Basic Cellular Structures Research Articles

Unraveling the Mechanisms of Valvular Heart Disease to Identify Medical Therapy Targets: A Scientific Statement From the American Heart Association.

Valvular heart disease is a common cause of morbidity and mortality worldwide and has no effective medical therapy. Severe disease is managed with valve replacement procedures, which entail high health care-related costs and postprocedural morbidity and mortality. Robust ongoing research programs have elucidated many important molecular pathways contributing to primary valvular heart disease. However, there remain several key challenges inherent in translating research on valvular heart disease to viable molecular targets that can progress through the clinical trials pathway and effectively prevent or modify the course of these common conditions. In this scientific statement, we review the basic cellular structures of the human heart valves and discuss how these structures change in primary valvular heart disease. We focus on the most common primary valvular heart diseases, including calcific aortic stenosis, bicuspid aortic valves, mitral valve prolapse, and rheumatic heart disease, and outline the fundamental molecular discoveries contributing to each. We further outline potential therapeutic molecular targets for primary valvular heart disease and discuss key knowledge gaps that might serve as future research priorities.

Morpho-anatomy and HPTLC Profiling of Senna Mill. Seeds Used in Traditional System of Indian Medicine

Pharmacognosy Research,2023,15,3,551-561.DOI:10.5530/pres.15.3.058Published:June 2023Type:Original Article Authors:Radha P, Divya KG, Udhayavani C, Murugammal S, Shakila R, and Sunil Kumar KN Author(s) affiliations:Radha P1,*, Divya KG2, Udhayavani C1, Murugammal S3, Shakila R3, Sunil Kumar KN3 1Department of Botany, Siddha Medicinal Plants Garden (Central Council for Research in Siddha, Ministry of Ayush, Govt. of India), Mettur Dam, Salem, Tamil Nadu, INDIA. 2Department of Pharmacognosy, Siddha Central Research Institute (Central Council for Research in Siddha, Ministry of Ayush, Govt. of India), Arumbakkam, Chennai, Tamil Nadu, INDIA. 3Department of Chemistry, Siddha Central Research Institute (Central Council for Research in Siddha, Ministry of Ayush, Govt. of India), Arumbakkam, Chennai, Tamil Nadu, INDIA. Abstract:Background: The present study was carried out to compare macro-microscopy, powder microscopy and HPTLC analysis of six species such as Senna auriculata (L.) Roxb., Senna alata (L.) Roxb., Senna alexandrina Mill., Senna occidentalis (L.) Link., S. uniflora (Mill.) Irwin and Barneby, S. tora (L.) Roxb. of the genus Senna Mill. belongs to the family Caesalpiniaceae. Materials and Methods: Six selected Senna species were collected, shade dried and pharmacognostic study were performed used techniques such as microscopy and HPTLC analysis. Results: Seed macro-morphology of the selected six species shows significant variations in size, shape, colour, ornamentation and number of seeds per pod. The basic cellular structure of six Senna species was anatomically similar but variation was observed in number of layers. Microscopic characters of the selected species revealed key diagnostic features that can help to determine the relationship between the closely related species; macrosclerieds and osteosclerdies were observed in Senna auriculata and S. occidentalis. Powder microscopy of selected six Senna species varied in colour, texture and odour. Numerous rosette crystals in cotyledonary cells were found only in Senna tora which is a significant variation from other five Senna species. HPTLC finger print profiling was performed with ethanol extract at 254 nm, 366 nm and 575 nm derivatization using vannilin-sulphuric acid and the results were documented. In 254 nm 14 bands were separated but the major peak at Rf 0.31 (22.24%) appeared in S. alexandrina. Conclusion: A detailed morphological and pharmacognostical evaluations play an important role to avoid misidentification and delimitation of selected six Senna species and HPTLC profiling is an additional analytical tool for species identification. Keywords:anatomy., S. alata, S. alexandrina, S. auriculata, S. occidentalis, S. tora, S. uniflora, SennaView:PDF (1.85 MB)

The Crucial Roles of Phospholipids in Aging and Lifespan Regulation.

Phospholipids are major membrane lipids that consist of lipid bilayers. This basic cellular structure acts as a barrier to protect the cell against various environmental insults and more importantly, enables multiple cellular processes to occur in subcellular compartments. Numerous studies have linked the complexity of membrane lipids to signal transductions, organelle functions, as well as physiological processes, and human diseases. Recently, crucial roles for membrane lipids in the aging process are beginning to emerge. In this study, we summarized current advances in our understanding of the relationship between membrane lipids and aging with an emphasis on phospholipid species. We surveyed how major phospholipid species change with age in different organisms and tissues, and some common patterns of membrane lipid change during aging were proposed. Further, the functions of different phospholipid molecules in regulating healthspan and lifespan, as well as their potential mechanisms of action, were also discussed.

Intelligent Classification and Analysis of Essential Genes Using Quantitative Methods

Essential genes are considered to be the genes required to sustain life of different organisms. These genes encode proteins that maintain central metabolism, DNA replications, translation of genes, and basic cellular structure, and mediate the transport process within and out of the cell. The identification of essential genes is one of the essential problems in computational genomics. In this present study, to discriminate essential genes from other genes from a non-biologists perspective, the purine and pyrimidine distribution over the essential genes of four exemplary species, namely Homo sapiens , Arabidopsis thaliana , Drosophila melanogaster , and Danio rerio are thoroughly experimented using some quantitative methods. Moreover, the Indigent classification method has also been deployed for classification on the essential genes of the said species. Based on Shannon entropy, fractal dimension, Hurst exponent, and purine and pyrimidine bases distribution, 10 different clusters have been generated for the essential genes of the four species. Some proximity results are also reported herewith for the clusters of the essential genes.

Transcriptomic Analysis of Leaf Sheath Maturation in Maize.

The morphological development of the leaf greatly influences plant architecture and crop yields. The maize leaf is composed of a leaf blade, ligule and sheath. Although extensive transcriptional profiling of the tissues along the longitudinal axis of the developing maize leaf blade has been conducted, little is known about the transcriptional dynamics in sheath tissues, which play important roles in supporting the leaf blade. Using a comprehensive transcriptome dataset, we demonstrated that the leaf sheath transcriptome dynamically changes during maturation, with the construction of basic cellular structures at the earliest stages of sheath maturation with a transition to cell wall biosynthesis and modifications. The transcriptome again changes with photosynthesis and lignin biosynthesis at the last stage of sheath tissue maturation. The different tissues of the maize leaf are highly specialized in their biological functions and we identified 15 genes expressed at significantly higher levels in the leaf sheath compared with their expression in the leaf blade, including the BOP2 homologs GRMZM2G026556 and GRMZM2G022606, DOGT1 (GRMZM2G403740) and transcription factors from the B3 domain, C2H2 zinc finger and homeobox gene families, implicating these genes in sheath maturation and organ specialization.

Reduction of Dimensionality in Monte Carlo Simulation of Diffusion in Extracellular Space Surrounding Cubic Cells.

The real-time iontophoretic method has measured volume fraction and tortuosity of the interstitial component of extracellular space in many regions and under different conditions. To interpret these data computer models of the interstitial space (ISS) of the brain are constructed by representing cells as Basic Cellular Structures (BCS) surrounded by a layer of ISS and replicating this combination to make a 3D ensemble that approximates brain tissue with a specified volume fraction. Tortuosity in such models is measured by releasing molecules of zero size into the ISS and allowing them to execute random walks in the ISS of the ensemble using a Monte Carlo algorithm. The required computational resources for such simulations may be high and here we show that in many situations the 3D problem may be reduced to a quasi-1D problem with consequent reduction in resources. We take the simplest BCS in the form of cubes and use MCell software to perform the Monte Carlo simulations but the analysis described here may be extended in principle to more complex BCS and an ISS that has a defined viscosity and an extracellular matrix that interacts with diffusing molecules. In the course of this study we found that the original analytical description of the relation between volume fraction and tortuosity for an ensemble of cubes may require a small correction.

‘Type 3’ diabetes: a brain insulin‐resistant state linked to Alzheimer's disease

‘Type 3’ diabetes: a brain insulin‐resistant state linked to Alzheimer's disease

Extracellular Matrix Revisited: Roles in Tissue Engineering.

The extracellular matrix (ECM) is a heterogeneous, connective network composed of fibrous glycoproteins that coordinate in vivo to provide the physical scaffolding, mechanical stability, and biochemical cues necessary for tissue morphogenesis and homeostasis. This review highlights some of the recently raised aspects of the roles of the ECM as related to the fields of biophysics and biomedical engineering. Fundamental aspects of focus include the role of the ECM as a basic cellular structure, for novel spontaneous network formation, as an ideal scaffold in tissue engineering, and its essential contribution to cell sheet technology. As these technologies move from the laboratory to clinical practice, they are bound to shape the vast field of tissue engineering for medical transplantations.

Paramagnetic levitational assembly of hydrogels.

Figure 1 . (A) Schematic of hydrogel fabrication process. Hydrogel units were fabricated by photolithography. 20 μ L of gel precursor solution was Tissues and organs are composed of repeating functional units. [ 1–3,48 ] Among these repeating basic cellular structures are the hexagonal lobule in liver, the nephron in kidney, and the islets in pankreas. [ 4–6 ] Tissue engineering aims to mimic the native 3D tissue architecture. [ 7 , 47 ] Engineered tissue constructs have broad applications in regenerative medicine [ 8–10 ] and physiological systems for pharmaceutical research. [ 11 ] In vivo , cells are surrounded by extracellular matrix (ECM), and exist in well-defi ned spatial organization with neighboring cells. Tissue functionality depends on these components, their interactions and relative spatial locations. [ 12–14 ] A high level of control over 3D tissue architecture has applications in identifying structure–function relationships in order to resolve underlying mechanisms and to model biological phenomena and diseases in vitro. Scaffolding and existing top-down approaches offer limited control over recapitulating 3D architecture and complex features of native tissues. [ 15 , 16 ] On the other hand, bottom-up methods aim to generate complex tissue structures by assembling building blocks, such as cell encapsulating microscale hydrogels. [ 4 , 17–22 ]

Acute cytotoxicity testing with cultured human lung and dermal cells.

An extensive in vitro study with cultured cells was conducted to test the basal cytotoxicity theory. This theory suggests that most chemical injury, at least in vitro, is a manifestation of one or more insults to the basic cellular structures and functions common to mammalian cells. This accounts for the similarity of results in multilaboratory studies. Human fetal lung fibroblasts (HFL1), and human skin fibroblasts (WS1, Detroit551) were studied in culture to evaluate their potential to screen for cytotoxicity. Confluent monolayers were incubated in the absence or presence of increasing concentrations of test chemicals for 24 h, and the MTT assay was used to assess toxicity. Inhibitory concentrations were extrapolated from concentration-effect curves after linear regression analysis. Twenty-nine chemicals were tested with each cell line and the cytotoxicity data compared to rodent and human lethal concentrations. The data suggest that the experimental IC50 values are as accurate predictors of human toxicity as equivalent toxic blood concentrations derived from rodent LD50s. In addition, lung and skin fibroblasts revealed no significant differences among the three cell lines. The results support the conclusion that finite cell lines of human origin have the potential for screening chemicals for human toxicity. In combination with previously published reports, the data suggest that a basal cytotoxic phenomenon may explain the similarity of results among different human cell lines.

Diagnostic Cytology and Its Histopathologic Bases

After almost a year's absence from the book stores, Koss's Diagnostic Cytology is back again in its second edition. This is probably the most complete book on cytology available, correlating the exfoliated cell with its parent healthy or diseased organ. As is the trend of modern texts, the new book is almost 300 pages longer than the original. Among its new features are a greatly expanded discussion of basic cellular structures with abundant photographs of electron microscopy. There also are several new chapters by Miles on the chromosome. Coverage of normal female genital-tract cytology has been increased by more illustrations of excellent quality. However, the second edition still describes what are probably metaplastic as parabasal with intercellular bridges. Another error has been corrected. In the new volume a special variety of multinucleated which previously had been called trophoblastic syncitial cells now is correctly identified as a cell

Pathophysiology and Diagnosis

IT SEEMS reasonable for me to be participating in the discussion of the town-gown syndrome and of the manifestations of morbidity which it presents. I am in a sense a split personality—I make my living looking after a private practice and I derive great pleasure from the position, Dean of Medical Students. The advantages of this double vision are obvious. I can assume an air of completely cool detachment collecting coldly calculated data, or with heated brow and obvious bias I can stand with either town or gown. It has thus been possible, as a hybrid, to observe and study the basic cellular structure of the pathophysiology of this disorder with the double standard, which the syndrome so richly deserves, of a scientist and a fishwife. It might first be in order to give the town-gown syndrome a proper eponym. Every syndrome worthy of consideration needs an eponym. The town-gown

COMPARATIVE CYTOLOGY AND THE EVOLUTION OF LIFE

During the first half of the present century very little interest was displayed in the subject of the possible evolutionary history of living things in general and in their true interrelationships. The past decade has shown a reawakening of concern over this aspect of biology, and many papers have attempted new approaches to the problem. Some have centered their interests in the origin of the Eumetazoa (Jagersten, 1955; Hansen, 1958), others have speculated upon the phylogeny of the Protozoa (Corliss, 1960; Kirby, 1949), while a few have dealt with the whole problem (Copeland, 1956; Hadzi, 1953; Whittaker, 1959). For the most part these studies have utilized as the bases for their phylogenies cellular pigments or their absence, cellular modes of locomotion, or similar grosser anatomical considerations; none have employed detailed comparisons of vital cell organelles or the ultra-structure of the latter. When one comes to consider the matter, why should not these internal organelles possibly reflect close relationships between organisms? It is a well-known fact that all Eumetazoa, despite multitudinous differences in ecology, show the same basic cellular organelles and mitotic processesa statement equally true for all the diverse seed-plants. If in these two great groups, external forces manifest no alteration in the fundamental morphology of the cells of their possessors, instances of parallel evolution in basic cellular structure might indeed be expected to be of extremely rare occurrence in other, simpler organisms. And why should not the organelles of a cell show an evolutionary history? After all, if life arose through biochemical means from inorganic substances, as seems fairly clear following the work of Oparin (1957) and others (Pringle, 1953; Abelson, 1956; Fox, 1960), is it not logical to suppose that the cell did not at once come into its ultimate state as found in the Eumetazoa and Metaphyta? If so, we might suppose that the cell arose originally in a very simple condition and gradually became more and more complex with the passage of time. Further, we might anticipate that some of the simpler stages in the evolution of the cell may conceivably be still represented in their fundamentals among organisms extant today. If such should prove to be the case, we would then have a means of investigating a possible evolutionary history of the cell-hence of life itself-and this history, in turn, would provide a key to the true interrelationships existing among all living things. To test the validity of these suppositions we can begin with the nuclear constituents of the various plants and animals, since the nucleus has been most thoroughly studied by cytologists, and see whether the various types can be arranged into some sort of logical phylogenetic sequence.