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Langmuir : the ACS Journal of Surfaces... Jan 2018By imposing vibration to a core-annular flow of an aqueous two-phase system (ATPS) with ultralow interfacial tension, we observe a liquid finger protruding from the...
By imposing vibration to a core-annular flow of an aqueous two-phase system (ATPS) with ultralow interfacial tension, we observe a liquid finger protruding from the interface of an expanding jet. We find that the protruded finger breaks up only when its length-to-width ratio exceeds a threshold value. The breakup follows a constant wavelength-to-width ratio that is consistent with that of breakup under Rayleigh-Plateau instability. The mechanism is applicable to aqueous two-phase systems with a large range of viscosity ratios. The protruded finger can break up into small droplets that are monodisperse in size, controllable in generation frequency under a wide range of flow rates. This work suggests a way to generate small water-water droplets with high monodispersity and production rate from a single nozzle.
PubMed: 29094601
DOI: 10.1021/acs.langmuir.7b02633 -
Rinsho Shinkeigaku = Clinical Neurology Dec 1993Motor impersistence is the term introduced by Fisher to describe the inability to sustain certain simple voluntary acts such as keeping eyes closed, protruding the... (Review)
Review
Motor impersistence is the term introduced by Fisher to describe the inability to sustain certain simple voluntary acts such as keeping eyes closed, protruding the tongue etc. He considered it a specific, nondominant hemisphere symptom, but some investigators denied its relationship to the right hemisphere damage. We considered that this difference might depend on the following two features of MI; the one is inability to maintain one of these simple acts so long as normal persons do, the other is inability to perform more than two of these acts simultaneously. When we attached importance to the latter feature and defined MI as inability to protrude the tongue with eyes closed, this phenomenon was clearly related to the right hemisphere damage. The responsible lesion was suggested to be located in area 6 or 8 in the territory of the right middle cerebral artery. The mechanism of MI was also reported.
Topics: Cerebrovascular Disorders; Dominance, Cerebral; Humans; Movement; Movement Disorders; Neurologic Examination; Psychomotor Performance
PubMed: 8174331
DOI: No ID Found -
Developmental Cell Feb 2018The differentiation of alveolar epithelial type I (AT1) and type II (AT2) cells is essential for the lung gas exchange function. Disruption of this process results in...
The differentiation of alveolar epithelial type I (AT1) and type II (AT2) cells is essential for the lung gas exchange function. Disruption of this process results in neonatal death or in severe lung diseases that last into adulthood. We developed live imaging techniques to characterize the mechanisms that control alveolar epithelial cell differentiation. We discovered that mechanical forces generated from the inhalation of amniotic fluid by fetal breathing movements are essential for AT1 cell differentiation. We found that a large subset of alveolar progenitor cells is able to protrude from the airway epithelium toward the mesenchyme in an FGF10/FGFR2 signaling-dependent manner. The cell protrusion process results in enrichment of myosin in the apical region of protruded cells; this myosin prevents these cells from being flattened by mechanical forces, thereby ensuring their AT2 cell fate. Our study demonstrates that mechanical forces and local growth factors synergistically control alveolar epithelial cell differentiation.
Topics: Alveolar Epithelial Cells; Animals; Cell Differentiation; Cell Movement; Cells, Cultured; Embryo, Mammalian; Female; Fibroblast Growth Factor 10; Mechanical Phenomena; Mesoderm; Mice; Mice, Knockout; Receptor, Fibroblast Growth Factor, Type 2; Signal Transduction
PubMed: 29408236
DOI: 10.1016/j.devcel.2018.01.008 -
Zhongguo Gu Shang = China Journal of... Apr 2009It is generally agreed that spinal manipulation has been applied into the treatment of lumbar intervertebral disc herniation (LDH) for thousands of years according to... (Review)
Review
It is generally agreed that spinal manipulation has been applied into the treatment of lumbar intervertebral disc herniation (LDH) for thousands of years according to historical reviews of the paper. The balance restore of spinal column had been always the main aim of spinal manipulation during the time. The situation has been changed after LDH was discovered pathomechanically about 70 years ago and the protruded nucleus pulposus has attracted the attention of whole world ever since and surgery become the major choice for LDH patients. Nevertheless, some latest reports of clinical observation in past decades explored more and more solid evidences to prove that most of the patients need no surgery at all and would be cured by conservative therapy without any changes of protruded nucleus pulposus at involved segment. The modern management of LDH suggests that we should not only pay attention to the protruded disk but also to the biomechanical balance of spinal column again as we had for thousands of years,which is concluded from the reviews of previous reports and history of LDH recognition in the paper. The only thing we should care more about is how to make full use of our modern knowledge to adjust our view of observation and management in clinical practice of spinal manipulation and to make a further understanding of the pathomechanics of LDH.
Topics: Humans; Intervertebral Disc Displacement; Lumbar Vertebrae; Manipulation, Spinal
PubMed: 19408757
DOI: No ID Found -
Journal of Microencapsulation Aug 2019This work describes viability and distribution of INS-1E beta cells in shell-crosslinked alginate capsules, focussing on cells located near the capsule surface. Capsules...
This work describes viability and distribution of INS-1E beta cells in shell-crosslinked alginate capsules, focussing on cells located near the capsule surface. Capsules were formed by air-shearing alginate suspensions of INS-1E cells into a gelling bath, and coating with poly-l-lysine (PLL) and 50% hydrolysed poly(methylvinylether-alt-maleic anhydride) to form crosslinked networks reinforcing the capsule surfaces. The percentage of cells at the capsule surface were determined using 2D and 3D confocal colocalization mapping. Encapsulated INS-1E cells showed high cell viability and progressive cell clustering out to six weeks. About 30% of cells were initially colocated with the 20 micrometer thick alginate-PLL-PMM50 shell, with 7% of cells protruded at the capsule surfaces, both reflecting random cell distributions. Protruding cells may cause cell-based immune responses, weaken capsules, and potentially result in cell escape from the capsules. The data shown indicate that reinforcing capsules with crosslinked shells may assist in preventing cell exposure and escape.
Topics: Alginates; Animals; Capsules; Cell Line; Cell Surface Extensions; Cell Survival; Cells, Immobilized; Cross-Linking Reagents; Gels; Insulin-Secreting Cells; Maleic Anhydrides; Polylysine; Rats
PubMed: 31401914
DOI: 10.1080/02652048.2019.1618404 -
Applied and Environmental Microbiology Oct 2019Large surface-to-volume ratios provide optimal nutrient uptake conditions for small microorganisms in oligotrophic habitats. The surface area can be increased with...
Large surface-to-volume ratios provide optimal nutrient uptake conditions for small microorganisms in oligotrophic habitats. The surface area can be increased with appendages. Here, we describe chains of interconnecting vesicles protruding from cells of strain Hel3_A1_48, affiliating with spp. within the and originating from coastal free-living bacterioplankton. The chains were up to 10 μm long and had vesicles emanating from the outer membrane with a single membrane and a size of 80 to 100 nm by 50 to 80 nm. Cells extruded membrane tubes in the exponential phase, whereas vesicle chains dominated on cells in the stationary growth phase. This formation is known as pearling, a physical morphogenic process in which membrane tubes protrude from liposomes and transform into chains of interconnected vesicles. Proteomes of whole-cell membranes and of detached vesicles were dominated by outer membrane proteins, including the type IX secretion system and surface-attached peptidases, glycoside hydrolases, and endonucleases. Fluorescein-labeled laminarin stained the cells and the vesicle chains. Thus, the appendages provide binding domains and degradative enzymes on their surfaces and probably storage volume in the vesicle lumen. Both may contribute to the high abundance of these -affiliated bacteria during laminarin utilization shortly after spring algal blooms. Microorganisms produce membrane vesicles. One synthesis pathway seems to be pearling that describes the physical formation of vesicle chains from phospholipid vesicles via extended tubes. Bacteria with vesicle chains had been observed as well as bacteria with tubes, but pearling was so far not observed. Here, we report the observation of, initially, tubes and then vesicle chains during the growth of a flavobacterium, suggesting biopearling of vesicle chains. The flavobacterium is abundant during spring bacterioplankton blooms developing after algal blooms and has a special set of enzymes for laminarin, the major storage polysaccharide of microalgae. We demonstrated with fluorescently labeled laminarin that the vesicle chains bind laminarin or contain laminarin-derived compounds. Proteomic analyses revealed surface-attached degradative enzymes on the outer membrane vesicles. We conclude that the large surface area and the lumen of vesicle chains may contribute to the ecological success of this marine bacterium.
Topics: Aquatic Organisms; Bacterial Outer Membrane Proteins; Cell Membrane; Eutrophication; Extracellular Vesicles; Flavobacterium; Glucans; Liposomes; Microscopy, Electron; Proteomics
PubMed: 31324630
DOI: 10.1128/AEM.00829-19 -
Cureus Feb 2023Pediatric vascular anomalies are classified into vascular malformations and vascular tumors. While vascular malformations are generally anomalous vessels, vascular...
Pediatric vascular anomalies are classified into vascular malformations and vascular tumors. While vascular malformations are generally anomalous vessels, vascular tumors arise from endothelial cells characterized by abnormal proliferation. Vascular tumors, also called hemangiomas, are subdivided into infantile and congenital hemangiomas. The differentiation of these anomalies can be challenging, and immunohistochemical staining is often employed for this purpose. The GLUT-1 (erythrocyte-type glucose transporter protein) stain is positive for the infantile type. Hemangiomas are usually found in the head and neck region. Their occurrence in the laryngeal region in infants tends to manifest in the subglottic region. Hemangiomas in the larynx mostly do not cause any symptoms until they are large enough to cause dyspnea, stridor, or hoarseness of voice. They are mostly treated in infants with propranolol or surgical excision. We report a case of an eight-day-old female infant who presented with a mass that recurrently protruded out of the mouth when she cried. The mass stopped protruding out of the mouth when the baby became restless, had respiratory distress, and refused feeds. Endoscopy of the pharynx and larynx showed a pedunculated hemorrhagic mass attached by a stalk to the left arytenoid. With cautery, the stalk of the lesion was severed from its attachment. The baby was discharged on the fourth postoperative day and histology reported a cavernous hemangioma. Seven months after the surgery, the baby is growing normally. Yearly follow-up endoscopies have been scheduled to evaluate for recurrence or residual disease.
PubMed: 36915847
DOI: 10.7759/cureus.34814 -
Parasitology Research Oct 2016Ultrastructural characteristics of the oncospheral hook morphogenesis in the taeniid cestode Echinococcus multilocularis Leuckart, 1863, a parasite of medical and...
Ultrastructural characteristics of the oncospheral hook morphogenesis in the taeniid cestode Echinococcus multilocularis Leuckart, 1863, a parasite of medical and veterinary importance, are described. Oncospheral hook primordia appear at the preoncospheral phase of the embryonic development. Within six specialised cells of the so-called oncoblasts, high concentration of mitochondria, numerous ribosomes and extended Golgi regions are involved in hook development. During hook growth, the blade and base gradually protrude outside the oncoblast plasma membrane. The nucleated oncoblast persists around the handles of fully formed hooks. Simultaneously with the hook primordium elongation and transformation into a blade, handle and base, the hook material differentiates into an electron-dense cortex and a less dense inner core. The exit of the blade of each mature hook, protruding from the oncosphere, is surrounded by a circular, septate desmosome and two rigid, dense rings on either side. The pattern of oncospheral hook morphogenesis in E. multilocularis is compared with that of other previously examined cyclophyllidean cestodes. Though oncoblasts have never been observed around the mature hooks, their remnants are often still visible in the fully developed infective oncospheres in particular in some taeniid species so far examined in this respect. The origin and formation of oncospheral hooks in E. multilocularis, evidently differs from that of the rostellar hooks. Thus, although the hooks may have slight similarity at the gross level, they are neither analogous nor homologous structures.
Topics: Animals; Echinococcosis; Echinococcus multilocularis; Embryonic Development; Female; Foxes; France; Golgi Apparatus; Mitochondria; Morphogenesis; Ribosomes
PubMed: 27206654
DOI: 10.1007/s00436-016-5131-1 -
Proceedings of the National Academy of... Mar 2016The actin cytoskeleton usually lies beneath the plasma membrane. When the membrane-associated actin cytoskeleton is transiently disrupted or the intracellular pressure...
The actin cytoskeleton usually lies beneath the plasma membrane. When the membrane-associated actin cytoskeleton is transiently disrupted or the intracellular pressure is increased, the plasma membrane detaches from the cortex and protrudes. Such protruded membrane regions are called blebs. However, the molecular mechanisms underlying membrane blebbing are poorly understood. This study revealed that epidermal growth factor receptor kinase substrate 8 (Eps8) and ezrin are important regulators of rapid actin reassembly for the initiation and retraction of protruded blebs. Live-cell imaging of membrane blebbing revealed that local reassembly of actin filaments occurred at Eps8- and activated ezrin-positive foci of membrane blebs. Furthermore, we found that a RhoA-ROCK-Rnd3 feedback loop determined the local reassembly sites of the actin cortex during membrane blebbing.
Topics: Actin Cytoskeleton; Adaptor Proteins, Signal Transducing; Cell Line; Cell Membrane; Cytoskeletal Proteins; Feedback, Physiological; Green Fluorescent Proteins; Humans; Microscopy, Fluorescence; rho GTP-Binding Proteins; rho-Associated Kinases; rhoA GTP-Binding Protein
PubMed: 26976596
DOI: 10.1073/pnas.1600968113 -
Methods in Molecular Biology (Clifton,... 2007Cell migration requires the formation of a leading pseudopodium (lamellipodium) in the direction of movement. This process requires signal amplification to facilitate...
Cell migration requires the formation of a leading pseudopodium (lamellipodium) in the direction of movement. This process requires signal amplification to facilitate directional sensing mechanisms that lead to actin-mediated membrane extension. However, it has been difficult to study pseudopodia formation because it has not been possible to purify this structure for biochemical analysis. Here we describe a method to biochemically purify the protruding pseudopodium from the cell body compartment using polycarbonate microporous filters. Cells are cultured on top of 3.0-microm porous filters and allowed to extend pseudopodia through the small pores to the undersurface in response to a gradient of either chemokine or extracellular matrix (ECM) protein. Pseudopodia and cell bodies are then differentially scraped from the filter surface into lysis buffer for biochemical analysis. Using this method, it is possible to identify novel pseudopodium and cell body proteins as well as study the spatiotemporal organization of signaling processes that regulate pseudopodium formation and cell polarity. This method will help facilitate our understanding of how cells protrude pseudopodia through small openings in the ECM and vasculature during cancer cell invasion, immune cell surveillance, and embryonic development.
Topics: Animals; COS Cells; Cell Movement; Chemokines; Chemotaxis; Chlorocebus aethiops; Cytoskeleton; Extracellular Matrix Proteins; Mice; Models, Biological; NIH 3T3 Cells; Pseudopodia; Signal Transduction
PubMed: 17416987
DOI: 10.1007/978-1-59745-353-0_5