Comparative morphology of spermathecae in solitary and primitively eusocial bees (Hymenoptera; Apoidea)

1996 ◽  
Vol 74 (5) ◽  
pp. 802-808 ◽  
Author(s):  
Noel Pabalan ◽  
K. G. Davey ◽  
Laurence Packer
Keyword(s):  
Epithelial Cell ◽  
Comparative Morphology ◽  
Thick Wall ◽  
Thin Wall ◽  
Cell Height ◽  
Large Numbers ◽  
Epithelial Cell Layer ◽  
Eusocial Bees ◽  
Spermathecal Gland ◽  
Primitively Eusocial

Spermathecae of solitary and primitively eusocial bees from five major families were compared according to their chamber size, epithelial cell height (wall thickness), number and shape of glands, number of sperm pumps, and diameter of the duct, using whole mounts and serial sections. A thick spermathecal wall with a small chamber in our exemplar colletid, megachilid, and andrenid bees, a large chamber with a thick wall in social Apidae, and a thin wall with a large chamber in social halictids indicate that a big chamber may be associated with increased colony size. A thin epithelium in the receptacle of halictid bees suggests relegation of spermathecal secretion to the spermathecal gland. A relatively thick spermathecal wall in the Apinae indicates the potential importance of both the epithelial cell layer of the receptacle and the enlarged spermathecal gland in maintaining large numbers of stored sperm. There was one sperm pump in all taxa surveyed except the representative Halictidae, in which this structure was paired. Elongated spermathecal glands may typify the spermathecae of eusocial bees.

1453: Lonidamine Reduces Prostate Weight in Rodents and is Accompanied by Apoptosis and Disruption of the Epithelial Cell Layer

2006 ◽  
Vol 175 (4S) ◽  
pp. 469-469
Author(s):  
W. Steve Ammons ◽  
Tatyana Lukoyanova ◽  
Amber Durnal ◽  
Geoffrey Del Rosario ◽  
Alan Colowick
Keyword(s):  
Epithelial Cell ◽  
Cell Layer ◽  
Prostate Weight ◽  
Epithelial Cell Layer

scholarly journals Therapeutic Potential of the Molecular Chaperone and Matrix Metalloproteinase Inhibitor Clusterin for Dry Eye

2020 ◽  
Vol 22 (1) ◽  
pp. 116
Author(s):  
M. Elizabeth Fini ◽  
Shinwu Jeong ◽  
Mark R. Wilson
Keyword(s):  
Epithelial Cell ◽  
Matrix Metalloproteinase ◽  
Dry Eye ◽  
Molecular Chaperone ◽  
Ocular Surface ◽  
Therapeutic Potential ◽  
Autoimmune Response ◽  
Interacting Protein ◽  
Bodily Fluids ◽  
Epithelial Cell Layer

Evidence is presented herein supporting the potential of the natural homeostatic glycoprotein CLU (clusterin) as a novel therapeutic for the treatment of dry eye. This idea began with the demonstration that matrix metalloproteinase MMP9 is required for damage to the ocular surface in mouse dry eye. Damage was characterized by degradation of OCLN (occludin), a known substrate of MMP9 and a key component of the paracellular barrier. Following up on this finding, a yeast two-hybrid screen was conducted using MMP9 as the bait to identify other proteins involved. CLU emerged as a strong interacting protein that inhibits the enzymatic activity of MMP9. Previously characterized as a molecular chaperone, CLU is expressed prominently by epithelia at fluid-tissue interfaces and secreted into bodily fluids, where it protects cells and tissues against damaging stress. It was demonstrated that CLU also protects the ocular surface in mouse dry eye when applied topically to replace the natural protein depleted from the dysfunctional tears. CLU is similarly depleted from tears in human dry eye. The most novel and interesting finding was that CLU binds selectively to the damaged ocular surface. In this position, CLU protects against epithelial cell death and barrier proteolysis, and dampens the autoimmune response, while the apical epithelial cell layer is renewed. When present at high enough concentration, CLU also blocks staining by vital dyes used clinically to diagnose dry eye. None of the current therapeutics have this combination of properties to “protect, seal, and heal”. Future work will be directed towards human clinical trials to investigate the therapeutic promise of CLU.

MICROSTRUCTURE ANALYSIS OF MOSO BAMBOO (Phyllostachys pubescens MAZEL) SURFACE AFTER UV RADIATION

2019 ◽  
Vol 27 (01) ◽  
pp. 1950090
Author(s):  
HAIXIA YU ◽  
XIN PAN ◽  
WEIMING YANG ◽  
WENFU ZHANG ◽  
XIAOWEI ZHUANG
Keyword(s):  
Uv Radiation ◽  
Cell Walls ◽  
Uv Light ◽  
Parenchyma Cell ◽  
Moso Bamboo ◽  
Thick Wall ◽  
Phyllostachys Pubescens ◽  
Thin Wall ◽  
Intercellular Spaces ◽  
Parenchyma Cell Walls

Bamboo material is widely used in outdoor applications. However, they are easily degraded when exposed to sunlight, their smooth surface will gradually turn to rough, and small cracks will appear and finally develop to large cracks. The paper presents a first-time investigation on the microstructure changes in the tangential section of Moso bamboo (Phyllostachys pubescens Mazel) radiated by artificial UV light. The results showed that the cracks mainly appeared at intercellular spaces of fibers where lignin content was high, the parenchyma cell walls and neighbor pits where the cell wall was very thin and more vulnerable than the other parts. In addition, the part of raised area and pit cavity tended to absorb more UV light radiation and showed more and larger cracks than the otherwhere. Cracks at the intercellular spaces of fibers were larger and bigger than those on the parenchyma cell walls. The cracks on the pits of the parenchyma cell walls normally appeared at one pit and then extended to the several surrounding pits. Bordered pits cavity showed more and larger cracks than the pits on the thin wall cells. The simple pits on the thick wall cells and the fiber cells were unaffected by UV radiation.

Development of Semi-Solid Die Casting Product Design and Die Design Technology for Aluminium Alloy Clamp

2016 ◽  
Vol 256 ◽  
pp. 334-339 ◽  
Author(s):  
Song Chen ◽  
Fan Zhang ◽  
You Feng He ◽  
Da Quan Li ◽  
Qiang Zhu
Keyword(s):  
Product Design ◽  
Die Casting ◽  
Casting Process ◽  
Die Design ◽  
Thick Wall ◽  
Thin Wall ◽  
Gating System ◽  
Cross Sectional ◽  
Die Casting Process ◽  
Semi Solid

Semi-solid slurry has significantly higher viscosity than liquid metal. This character of fluidity makes product design and die design, such as gating system, overflow and venting system, be different between these two die casting processes. In the present paper, taking a clamp product as an example, analyses the product optimization and die design by comparing the experimental and computational numerical simulation results. For the clamp, product structure is designed to be suitable for characters of SSM die casting process. The gating system is designed to be uniform variation of thickness, making the cross-sectional area uniformly reduce from the biscuit to the gate. This design ensures semi-solid metal slurry to fill die cavity from thick wall to thin wall. Gate position is designed at the thickest location, the gate shape of semi-solid die casting is set to be much bigger than traditional liquid casting. A good filling behaviour can be achieved by aforementioned all these design principles and it will be helpful to the intensification of pressure feeding after filling.

scholarly journals Infection with Rhinovirus Facilitates Allergen Penetration Across a Respiratory Epithelial Cell Layer

2015 ◽  
Vol 166 (4) ◽  
pp. 291-296 ◽  
Author(s):  
Katharina Gangl ◽  
Eva E. Waltl ◽  
Helga Vetr ◽  
Clarissa R. Cabauatan ◽  
Katarzyna Niespodziana ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Cell Layer ◽  
Respiratory Epithelial Cell ◽  
Epithelial Cell Layer ◽  
Respiratory Epithelial

Abstract 19170: Lesion Morphological Classification by Optical Coherence Tomography to Predict Therapeutic Efficacy After Balloon Pulmonary Angioplasty

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Taku Inohara ◽  
Takashi Kawakami ◽  
Masaharu Kataoka ◽  
Keiichi Fukuda
Keyword(s):  
Optical Coherence Tomography ◽  
Therapeutic Efficacy ◽  
Pressure Ratio ◽  
Chronic Thromboembolic Pulmonary Hypertension ◽  
Thick Wall ◽  
Thin Wall ◽  
Optical Coherence ◽  
Pressure Wire ◽  
Balloon Pulmonary Angioplasty ◽  
Lesion Morphology

Introduction: Conventionally, angiographic classification has been used for chronic thromboembolic pulmonary hypertension (CTEPH). However, a classification based on lesion morphology is needed in the era of balloon pulmonary angioplasty (BPA). We sought to propose a classification of CTEPH based on lesion morphology detected by optical coherence tomography (OCT) and to evaluate its association with physiological stenosis assessed with a pressure wire and therapeutic efficacy in BPA. Methods: We analyzed 43 lesions in 17 patients who were treated with BPA under OCT and pressure-wire guidance from November 2012 to March 2015. OCT findings were classified into the following 4 categories: 1) mono-hole, 2) septum, 3) multi-hole with thin wall, and 4) multi-hole with thick wall. Results: Angiographic findings did not match the specific morphologic classification based on OCT findings. At the pre-BPA assessment, the pressure ratio of the septum type was significantly higher than that of the mono-hole and multi-hole with thick wall types (p = 0.026 and 0.047, respectively). Under the OCT-based classification, more than 50% of the septum and multi-hole with thin wall types could accomplish >0.8 of the mean pressure ratio assessed by a pressure wire, and these proportions were significantly higher than those of the other 2 types: mono-hole and multi-hole with thick wall (p = 0.044). Based on angiographic classification, accomplishment of this criterion was not significantly different among angiographic types. Conclusions: OCT-based morphologic lesion classifications in CTEPH were useful to predict whether the lesion stenosis could improve to the acceptable level mediated by BPA.

Study on Crashworthiness Characteristics of Several Concentric Thin Wall Tubes

2010 ◽  
Author(s):  
Parisa Hosseini Tehrani ◽  
Sajad Pirmohammad
Keyword(s):  
Finite Element ◽  
Optimum Combination ◽  
Thick Wall ◽  
Thin Wall ◽  
Finite Element Program ◽  
Linear Dynamic ◽  
Wall Structures ◽  
Moving Body ◽  
Oblique Loading ◽  
Element Program

There is a growing interest in the use of thin-wall structures as a means of absorbing the kinetic energy of a moving body. Multi-layered thin-wall structures are more efficient and lighter than thick-wall structures, and show better crashworthiness characteristics. In this task, several concentric aluminum thin wall tubes as energy absorber under axial and oblique loading are studied and optimum combination of these tubes is presented. The weight of the tubes is optimized while crashworthiness of tubes is not compromised. The commercial finite element program LS-DYNA that offers non-linear dynamic simulation capabilities was used in this study.

QUANTUM TUNNELLING OR THERMAL HOPPING

2000 ◽  
Vol 14 (19n20) ◽  
pp. 2109-2116
Author(s):  
N. PANCHAPAKESAN
Keyword(s):  
Quantum Tunneling ◽  
Condensed Matter ◽  
Order Term ◽  
Thick Wall ◽  
Thin Wall ◽  
Quantum Tunnelling ◽  
First Order ◽  
Classical State ◽  
Fourth Order Term ◽  
Loss Of Coherence

The nature of the transition from the quantum tunneling regime to the thermal hopping regime has importance in the study of condensed matter physics and cosmological phase transitions. It may also be of significance in collapse from quantum state to a classical state due to measurement (or loss of coherence due to some other process). We study this transition analytically in scalar field theory with a fourth order term. We obtain analytic bounce solutions which correctly give the action in thin and thick wall limits of the potential. We find that the transition is of the second order for the case of thick wall while it seems to be of first order for the case of thin wall.

scholarly journals Infection of bovine well-differentiated airway epithelial cells by Pasteurella multocida: actions and counteractions in the bacteria–host interactions

2020 ◽  
Vol 51 (1) ◽  
Author(s):  
Ang Su ◽  
Jie Tong ◽  
Yuguang Fu ◽  
Sandy Müller ◽  
Yenehiwot Berhanu Weldearegay ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Cell Layer ◽  
Airway Epithelial Cells ◽  
Infection Model ◽  
Target Cells ◽  
Respiratory Disorder ◽  
Airway Epithelial ◽  
Epithelial Cell Layer ◽  
Well Differentiated

AbstractPasteurella (P.) multocida is a zoonotic pathogen, which is able to cause respiratory disorder in different hosts. In cattle, P. multocida is an important microorganism involved in the bovine respiratory disease complex (BRDC) with a huge economic impact. We applied air–liquid interface (ALI) cultures of well-differentiated bovine airway epithelial cells to analyze the interaction of P. multocida with its host target cells. The bacterial pathogen grew readily on the ALI cultures. Infection resulted in a substantial loss of ciliated cells. Nevertheless, the epithelial cell layer maintained its barrier function as indicated by the transepithelial electrical resistance and the inability of dextran to get from the apical to the basolateral compartment via the paracellular route. Analysis by confocal immunofluorescence microscopy confirmed the intactness of the epithelial cell layer though it was not as thick as the uninfected control cells. Finally, we chose the bacterial neuraminidase to show that our infection model is a sustainable tool to analyze virulence factors of P. multocida. Furthermore, we provide an explanation, why this microorganism usually is a commensal and becomes pathogenic only in combination with other factors such as co-infecting microorganisms.

Failure properties of 352 explanted silicone-gel breast implants

1996 ◽  
Vol 4 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Walter Peters ◽  
Dennis Smith ◽  
Stanley Lugowski
Keyword(s):  
First Generation ◽  
Second Generation ◽  
Survival Curve ◽  
Breast Implants ◽  
Thick Wall ◽  
Thin Wall ◽  
Third Generation ◽  
Silicone Gel ◽  
Failure Properties

There have been three generations of silicone-gel breast implants. First generation implants (thick wall – thick gel with Dacron patches) were made from 1963 to 1972. Second generation implants (thin wall-thin gel) were made from 1972 until the mid 1980s. The introduction of third generation implants (stronger wall, low-bleed) was geographically dependent. In Canada, Dow Corning Silastic II implants were introduced in 1986, and Surgitek SCL implants were introduced in 1988. In the present study, a total of 352 silicone-gel breast implants were removed from 239 patients between 1981 and 1995. Their failure properties were dependent upon their generation (year of manufacture) and, for second generation implants, their duration in situ. Of the 352 implants, 20 were first generation, and all were fully intact. Twenty-eight were third generation implants, and 27 were fully intact. Failure properties of the 302 second generation implants were dependent upon their duration of implantation. A survival curve indicated that these implants began to fail (by leaking or rupturing) after four years in situ. By six years, 40% had failed. After 12 years, 95% had failed. Of the 171 second generation implants removed between 1991 and 1995, 77% had failed. The failure properties were similar for the three main manufacturers: Dow Corning, Heyer-Schulte and Surgitek. The failure rate for second generation implants is much higher than was previously believed. This is particularly significant in view of the current difficulty in diagnosing implant failure.

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