scholarly journals Role of Crop Load in Chloroplast Ultra-structure and Zonal Chlorosis, a Physiological Disorder in ‘Honeycrisp’ Apple Trees

HortScience ◽  
2008 ◽  
Vol 43 (6) ◽  
pp. 1819-1822 ◽  
Author(s):  
Teresa Eileen Snyder-Leiby ◽  
Shixiong Wang
Keyword(s):  
Membrane Structure ◽  
Potato Leafhopper ◽  
Ultrastructural Changes ◽  
Apple Cultivar ◽  
Physiological Disorder ◽  
Crop Load ◽  
Starch Grains ◽  
Transmission Electron ◽  
Starch Grain

‘Honeycrisp’ is a relatively new apple cultivar (Malus ×domestica Borkh.) with a unique crisp fruit texture that makes it highly desirable. However, the leaves often develop a zonal chlorosis that resembles potato leafhopper damage. Other researchers have determined that the symptoms correlate with decreasing crop load rather than leafhopper damage. This study investigates the possibility that the zonal chlorosis is related to the buildup of starch grains causing rupture of chloroplasts. Transmission electron microscopy was used to document ultrastructural changes in chloroplasts in trees with three different crop loads from the beginning of the season to the end of the season. In trees with extremely low crop loads, we observed abnormalities of chloroplast membrane structure and accumulation of larger and more numerous starch grains. These appear before the appearance of chlorotic symptoms. By early August, the chloroplasts from chlorotic regions of leaves on trees with light crop loads are completely disrupted and abnormally large starch grains are found in place of chloroplasts. As the season progresses, trees with moderate and heavy crop loads showed less severe chloroplast disruption and smaller starch grain accumulation than trees with light crop load.

Ultrastructural Changes in Root Cap Cells of Two Australian Native Grass Species Following Exposure to Aluminium

1997 ◽  
Vol 24 (2) ◽  
pp. 165 ◽  
Author(s):  
Simon A. Crawford ◽  
Sabine Wilkens
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Root Cap ◽  
Ultrastructural Changes ◽  
Grass Species ◽  
Aluminium Tolerance ◽  
Secretory Vesicles ◽  
Native Grass ◽  
Transmission Electron

Transmission electron microscopy was used to investigate ultrastructural changes in root cap cells of two aluminium-tolerant native grass species, Danthonia linkii Kunth and Microlaena stipoides (Labill.) R.Br., following exposure to Al. Quantitative differences in root cap cells and organelles in response to 0–10 ppm aluminium were determined using image analysis of electron micrographs. Changes to the size of root cap cells due to exposure to Al were similar in the two species with a low Al concentration (1–2 ppm) resulting in larger cells, while higher Al levels (5–10 ppm) reduced cell size. In peripheral cap cells of the more Al-tolerant M. stipoides, the size of secretory vesicles was not affected by exposure to Al, while in peripheral cap cells of the less Al-tolerant D. linkii, exposure to Al resulted in significantly smaller secretory vesicles being produced. Central root cap cells from control plants of M. stipoides contained 90% more dictyosomes and had 50% larger amyloplasts than D. linkii. Measurement of mucilage droplets showed that roots of M. stipoides produced much more mucilage than D. linkii. Exposure of roots of M. stipoides to Al in the range 2–10 ppm had no effect on the size of mucilage droplets produced. The possible role of mucilage production in aluminium tolerance is discussed.

Ultrastructural changes in murine lymphoma cells exposed to ultraviolet-A radiation

1991 ◽  
Vol 49 ◽  
pp. 104-105
Author(s):  
Delma P. Thomas ◽  
Dianne E. Godar
Keyword(s):  
Medical Devices ◽  
Blood Cells ◽  
White Blood Cells ◽  
Consumer Products ◽  
Ultrastructural Changes ◽  
Ultraviolet A ◽  
Uv Spectrum ◽  
Lymphoma Cells ◽  
Murine Lymphoma ◽  
Transmission Electron

Ultraviolet radiation (UVR) from all three waveband regions of the UV spectrum, UVA (320-400 nm), UVB (290-320 nm), and UVC (200-290 nm), can be emitted by some medical devices and consumer products. Sunlamps can expose the blood to a considerable amount of UVR, particularly UVA and/or UVB. The percent transmission of each waveband through the epidermis to the dermis, which contains blood, increases in the order of increasing wavelength: UVC (10%) < UVB (20%) < UVA (30%). To investigate the effects of UVR on white blood cells, we chose transmission electron microscopy to examine the ultrastructure changes in L5178Y-R murine lymphoma cells.

On Future Directions in Pathology

1982 ◽  
Vol 40 ◽  
pp. 274-277
Author(s):  
Benjamin F. Trump ◽  
Irene K. Berezesky ◽  
Raymond T. Jones
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Clinical Pathology ◽  
Future Directions ◽  
Diagnostic Pathology ◽  
The Past ◽  
Transmission Electron ◽  
Organ Systems ◽  
The Many

The role of electron microscopy and associated techniques is assured in diagnostic pathology. At the present time, most of the progress has been made on tissues examined by transmission electron microscopy (TEM) and correlated with light microscopy (LM) and by cytochemistry using both plastic and paraffin-embedded materials. As mentioned elsewhere in this symposium, this has revolutionized many fields of pathology including diagnostic, anatomic and clinical pathology. It began with the kidney; however, it has now been extended to most other organ systems and to tumor diagnosis in general. The results of the past few years tend to indicate the future directions and needs of this expanding field. Now, in addition to routine EM, pathologists have access to the many newly developed methods and instruments mentioned below which should aid considerably not only in diagnostic pathology but in investigative pathology as well.

Transmission Electron Microscopy studies of texture of Cr underlayer of magnetic recording hard disk

1991 ◽  
Vol 49 ◽  
pp. 580-581
Author(s):  
L. Tang ◽  
G. Thomas ◽  
M. R. Khan ◽  
S. L. Duan
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Magnetic Recording ◽  
Magnetic Thin Films ◽  
Magnetic Films ◽  
Substrate Bias ◽  
Epitaxial Relationship ◽  
Transmission Electron

Cr thin films are often used as underlayers for Co alloy magnetic thin films, such as Co1, CoNi2, and CoNiCr3, for high density longitudinal magnetic recording. It is belived that the role of the Cr underlayer is to control the growth and texture of the Co alloy magnetic thin films, and, then, to increase the in plane coercivity of the films. Although many epitaxial relationship between the Cr underlayer and the magnetic films, such as ﹛1010﹜Co/ {110﹜Cr4, ﹛2110﹜Co/ ﹛001﹜Cr5, ﹛0002﹜Co/﹛110﹜Cr6, have been suggested and appear to be related to the Cr thickness, the texture of the Cr underlayer itself is still not understood very well. In this study, the texture of a 2000 Å thick Cr underlayer on Nip/Al substrate for thin films of (Co75Ni25)1-xTix dc-sputtered with - 200 V substrate bias is investigated by electron microscopy.

Transmission Electron Microscopy of Evaporated Perylene Thin Films

1990 ◽  
Vol 48 (2) ◽  
pp. 336-337
Author(s):  
C. Ewins ◽  
J.R. Fryer
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Molecular Electronics ◽  
High Vacuum ◽  
Amorphous Layer ◽  
Electric Heater ◽  
Transmission Electron ◽  
Polycyclic Aromatic

The preparation of thin films of organic molecules is currently receiving much attention because of the need to produce good quality thin films for molecular electronics. We have produced thin films of the polycyclic aromatic, perylene C10H12 by evaporation under high vacuum onto a potassium chloride (KCl) substrate. The role of substrate temperature in determining the morphology and crystallography of the films was then investigated by transmission electron microscopy (TEM).The substrate studied was the (001) face of a freshly cleaved crystal of KCl. The temperature of the KCl was controlled by an electric heater or a cold finger. The KCl was heated to 200°C under a vacuum of 10-6 torr and allowed to cool to the desired temperature. The perylene was then evaporated over a period of one minute from a molybdenum boat at a distance of 10cm from the KCl. The perylene thin film was then backed with an amorphous layer of carbon and floated onto copper microscope grids.

Morphologic alteration in the muscles of patients with hypokalemic periodic paralysis or myopathy

1990 ◽  
Vol 48 (3) ◽  
pp. 222-223
Author(s):  
T. Shimizu ◽  
Y. Muranaka ◽  
I. Ohta ◽  
N. Honda
Keyword(s):  
Clinical Manifestations ◽  
Quadriceps Muscle ◽  
Honeycomb Structure ◽  
Periodic Paralysis ◽  
Ultrastructural Changes ◽  
Hypokalemic Periodic Paralysis ◽  
Electron Microscopic ◽  
Tubular Aggregates ◽  
Hypokalemic Myopathy ◽  
Transmission Electron

There have been many reports on ultrastructural alterations in muscles of hypokalemic periodic paralysis (hpp) and hypokalemic myopathy(hm). It is stressed in those reports that tubular structures such as tubular aggregates are usually to be found in hpp as a characteristic feature, but not in hm. We analyzed the histological differences between hpp and hm, comparing their clinical manifestations and morphologic changes in muscles. Materials analyzed were biopsied muscles from 18 patients which showed muscular symptoms due to hypokalemia. The muscle specimens were obtained by means of biopsy from quadriceps muscle and fixed with 2% glutaraldehyde (pH 7.4) and analyzed by ordinary method and modified Golgimethod. The ultrathin section were examined in JEOL 200CX transmission electron microscopy.Electron microscopic examinations disclosed dilated t-system and terminal cistern of sarcoplasmic reticulum (SR)(Fig 1), and an unique structure like “sixad” was occasionally observed in some specimens (Fig 2). Tubular aggregates (Fig 3) and honeycomb structure (Fig 4) were also common characteristic structures in all cases. These ultrastructural changes were common in both the hypokalemic periodic paralysis and the hypokalemic myopathy, regardless of the time of biopsy or the duration of hypokalemia suffered.

Fine structure and possible functions of the hermaphrodite duct of some pulmonate snails (Mollusca: Gastropoda)

1990 ◽  
Vol 48 (3) ◽  
pp. 68-69
Author(s):  
Alan N. Hodgson
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Seminal Vesicle ◽  
Reproductive Biology ◽  
Light Microscope ◽  
Light Microscope Level ◽  
Transmission Electron ◽  
Standard Techniques

The hermaphrodite duct of pulmonate snails connects the ovotestis to the fertilization pouch. The duct is typically divided into three zones; aproximal duct which leaves the ovotestis, the middle duct (seminal vesicle) and the distal ovotestis duct. The seminal vesicle forms the major portion of the duct and is thought to store sperm prior to copulation. In addition the duct may also play a role in sperm maturation and degredation. Although the structure of the seminal vesicle has been described for a number of snails at the light microscope level there appear to be only two descriptions of the ultrastructure of this tissue. Clearly if the role of the hermaphrodite duct in the reproductive biology of pulmonatesis to be understood, knowledge of its fine structure is required.Hermaphrodite ducts, both containing and lacking sperm, of species of the terrestrial pulmonate genera Sphincterochila, Levantina, and Helix and the marine pulmonate genus Siphonaria were prepared for transmission electron microscopy by standard techniques.

Hepatocyte ultrastructural alterations in perimetastatic areas

1996 ◽  
Vol 54 ◽  
pp. 768-769
Author(s):  
H. J. Finol ◽  
M. E. Correa ◽  
L.A. Sosa ◽  
A. Márquez ◽  
N.L. Díaz
Keyword(s):  
Malignant Tumor ◽  
Malignant Tumors ◽  
Surrounding Tissue ◽  
Ultrastructural Changes ◽  
Pancreas Carcinoma ◽  
Duct Carcinoma ◽  
Tissue Samples ◽  
Primary Malignant Tumor ◽  
Transmission Electron ◽  
Remote Sites

In classical oncological literature two mechanisms for tissue aggression in patients with cancer have been described. The first is the progressive invasion, infiltration and destruction of tissues surrounding primary malignant tumor or their metastases; the other includes alterations produced in remote sites that are not directly affected by any focus of disease, the so called paraneoplastic phenomenon. The non-invaded tissue which surrounds a primary malignant tumor or its metastases has been usually considered a normal tissue . In this work we describe the ultrastructural changes observed in hepatocytes located next to metastases from diverse malignant tumors.Hepatic biopsies were obtained surgically in patients with different malignant tumors which metatastized in liver. Biopsies included tumor mass, the zone of macroscopic contact between the tumor and the surrounding tissue, and the tissue adjacent to the tumor but outside the macroscopic area of infiltration. The patients (n = 5), 36–75 years old, presented different tumors including rhabdomyosarcoma, leiomyosarcoma, pancreas carcinoma, biliar duct carcinoma and colon carcinoma. Tissue samples were processed with routine techniques for transmission electron microscopy and observed in a Hitachi H-500 electron microscope.

scholarly journals Fine Morphology of Antennal and Ovipositor Sensory Structures of the Gall Chestnut Wasp, Dryocosmus kuriphilus

Insects ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 231
Author(s):  
Milos Sevarika ◽  
Marco Valerio Rossi Stacconi ◽  
Roberto Romani
Keyword(s):  
Ultrastructural Organization ◽  
Antennal Sensilla ◽  
Dryocosmus Kuriphilus ◽  
Transmission Electron ◽  
Significant Damage ◽  
Sensory Structures ◽  
Host Plant Location ◽  
Oviposition Sites ◽  
Fine Morphology

Dryocosmus kuriphilus is a gall-inducing insect, which can cause significant damage on plants of the genus Castanea Mill., 1754. Antennae and ovipositor are the main sensory organs involved in the location of suitable oviposition sites. Antennal sensilla are involved in the host plant location, while ovipositor sensilla assess the suitability of the ovipositional bud. On both organs, diverse sensillar organs are present. Here, the distribution and ultrastructural organization of the sensilla were investigated by scanning and transmission electron microscopy. The antennae of D. kuriphilus are filiform and composed of 14 antennomeres, with the distal flagellomere bearing the highest number of sensilla. On the antennae, 6 sensilla types were found; sensilla chaetica, campaniformia, coeloconica-I, coeloconica-II, trichoidea and placoidea. The sensilla placoidea and trichoidea were the most abundant types. On the external walls of the ovipositor, gustatory and mechanoreceptive sensilla were observed. Internally, the egg channel hosted two additional sensory structures. The putative functional role of each sensilla in the context of insect’s ecology is discussed as well as the ovipositional mechanism used by this insect.

The Effect Of Storage On Platelet Morpholog

1981 ◽  
Author(s):  
A Sturk ◽  
L M Burt ◽  
T Hakvoort ◽  
J W ten cate ◽  
N Crawford
Keyword(s):  
Electron Microscopy ◽  
Membrane Structure ◽  
Room Temperature ◽  
Surface Membrane ◽  
Platelet Concentrates ◽  
Room Temperature Storage ◽  
Short Survival ◽  
Transmission Electron ◽  
Temperature Storage ◽  
Morphological Correlation

Platelet concentrates were stored for one, two or three days at 4°C (unagitated) or room temperature (unagitated and linearly agitated). The morphology of platelets in platelet concentrates, directly after twice washing at room temperature and after 60 min incubation of the washed platelets at 37°C was investigated by both scanning and transmission electron microscopy.Platelets in the freshly prepared concentrates are slightly activated, i.e. show some pseudopod formation. At 4°C platelets rapidly loose their discoid shape. After three days their surface membrane shows extensive folding, they are slightly vacuolated and have lost most of their granules. Incubation of these cold-stored platelets at 37°C does not induce reversal to the discoid shape.Room temperature storage results in reversal of the slight initial platelet activation. After three days unagitated platelets are slightly more vacuolated than platelets stored with agitation. Room temperature storage usually results in remarkably well preserved, discoid platelets. Occasionally however, agitated platelet concentrates contain a high proportion of odd shaped cells. As platelets stored at 4°C did not became discoid after incubation at 37°, the altered membrane structure could provide an explanation for their short survival upon transfusion. Our results also provide a morphological correlation with the slightly better recovery and survival of platelets stored agitated vs.- non-agitated platelets at room temperature.

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