Bacterial suppression of basal pod rot and end rot of dry peas caused by Sclerotinia sclerotiorum

1993 ◽  
Vol 39 (2) ◽  
pp. 227-233 ◽  
Author(s):  
H. C. Huang ◽  
E. G. Kokko ◽  
L. J. Yanke ◽  
R. C. Phillippe
Keyword(s):  
Bacillus Cereus ◽  
Sclerotinia Sclerotiorum ◽  
Lesion Size ◽  
Development Stage ◽  
In Vivo Studies ◽  
Bacterial Strains ◽  
Electron Microscopic ◽  
Microscopic Studies

Morphological and biochemical characteristics indicate that the two bacterial strains used in this study belong to Bacillus cereus Frankland and Frankland. Tests in vitro revealed that strains of B. cereus differ in their antagonistic activities on Sclerotinia sclerotiorum (Lib.) de Bary. Vegetative growth and ascospore germination of S. sclerotiorum were inhibited by diffusible metabolites induced by B. cereus strain alf-87A, but were unaffected by strain B43. In vivo studies showed that the antagonistic strain alf-87A, when sprayed onto pea plants (Pisum sativum L.) at the pod development stage, reduced the incidence of basal pod rot from infection by airborne ascospores of S. sclerotiorum by 39–55%. This treatment also significantly (P < 0.05) reduced the severity of basal pod rot by decreasing lesion size. Strain alf-87A significantly reduced the incidence of end pod rot. Spraying pea plants with strain B43 of B. cereus was not consistently effective in reducing basal and end pod rots. Scanning electron microscopic studies revealed that both strains of B. cereus could colonize senescing pea stamens but only the antagonistic strain alf-87A was consistently effective in controlling sclerotinia basal and end pod rots of dry peas.Key words: Sclerotinia sclerotiorum, Bacillus cereus, basal pod rot, end pod rot, stamens, ascospores, apothecia.

Biopharmaceutical and Preclinical Studies of Zaleplon as Semisolid Dispersions with Self-emulsifying Lipid Surfactants for Oral Delivery

1970 ◽  
Vol 9 (1) ◽  
pp. 3102-3111
Author(s):  
Narendar Dudhipala ◽  
Arjun Narala ◽  
Dinesh Suram ◽  
Karthik Yadav Janga
Keyword(s):  
Oral Delivery ◽  
Molecular State ◽  
In Vivo Studies ◽  
In Vitro Dissolution ◽  
Content Uniformity ◽  
Phase Solubility ◽  
Microscopic Studies ◽  
Pure Drug

The objective of this present study is to develop a semisolid dispersion (SSD) of zaleplon with the aid of self-emulsifying lipid based amphiphilic carriers (TPGS E or Gelucire 44/14) addressing the poor solubility of this drug. A linear relationship between the solubility of drug with respect to increase in the concentration of lipid surfactant in aqueous medium resulting in AL type phase diagram was observed from phase solubility studies. Fusion method was employed to obtain semisolid dispersions (SSD) of zaleplon which showed high content uniformity of drug. The absence of chemical interactions between the pure drug, excipients and formulations were conferred by Fourier transmission infrared spectroscopic examinations. The photographic images from polarized optical microscopic studies revealed the change in crystalline form of drug to amorphous or molecular state. The superior dissolution parameters of zaleplon from SSD over pure crystalline drug interpreted from in vitro dissolution studies envisage the ability of these lipid surfactants as solubility enhancers. Further, the caliber of TPGS E or Gelucire 44/14 in encouraging the GI absorption of drug was evident with the higher human effective permeability coefficient and fraction oral dose of drug absorbed from SSD in situ intestinal permeation study. In conclusion, in vivo studies in Wister rats demonstrated an improvement in the oral bioavailability of zaleplon from SSD over control pure drug suspension suggesting the competence of Gelucire 44/14 and TPGS E as conscientious carriers to augment the dissolution rate limited bioavailability of this active

Electron microscopic studies on the structure of motile primordial germ cells of Xenopus laevis in vitro

Development ◽  
1978 ◽  
Vol 46 (1) ◽  
pp. 119-133
Author(s):  
Janet Heasman ◽  
C. C. Wylie
Keyword(s):  
Xenopus Laevis ◽  
Germ Cells ◽  
Primordial Germ Cells ◽  
Structural Features ◽  
Culture Conditions ◽  
Structural Basis ◽  
Electron Microscopic ◽  
Microscopic Studies

Primordial germ cells (PGCs) of Xenopus laevis have been isolated from early embryos and kept alive in vitro, in order to study the structural basis of their motility, using the transmission and scanning electron microscope. The culture conditions used mimicked as closely as possible the in vivo environment of migrating PGCs, in that isolated PGCs were seeded onto monolayers of amphibian mesentery cells. In these conditions we have demonstrated that: (a) No significant differences were found between the morphology of PGCs in vitro and in vivo. (b) Structural features involved in PGC movement in vitro include (i) the presence of a filamentous substructure, (ii) filopodial and blunt cell processes, (iii) cell surface specializations. These features are also characteristic of migratory PGCs studied in vivo. (c) PGCs in vitro have powers of invasion similar to those of migrating PGCs in vivo. They occasionally become completely surrounded by cells of the monolayer and, in this situation, bear striking resemblance to PGCs moving between mesentery cells to the site of the developing gonad in stage-44 tadpoles. We conclude that as far as it is possible to assess, the behaviour of isolated PGCs in these in vitro conditions mimics their activities in vivo. This allows us to study the ultrastructural basis of their migration.

scholarly journals Platelet Satellitism

Blood ◽  
1974 ◽  
Vol 43 (6) ◽  
pp. 831-836 ◽  
Author(s):  
Carl R. Kjeldsberg ◽  
John Swanson
Keyword(s):  
Polymorphonuclear Leukocytes ◽  
Plasma Membranes ◽  
Clinical Importance ◽  
Electron Microscopic ◽  
Normal Platelet ◽  
Microscopic Studies ◽  
Platelet Satellitism ◽  
Platelet Functions

Abstract Platelet adherence to polymorphonuclear leukocytes, or so-called platelet satellitism, has, to our knowledge, been reported in only four patients. We had the opportunity to study this phenomenon in two patients. Platelet satellitism was only seen in EDTA anticoagulated blood, and the platelets were seen to surround polymorphonuclear leukocytes only. Electron microscopic studies demonstrated focally opposed regions of platelet and neutrophil plasma membranes. Phagocytosis of platelets was also observed. In vivo and in vitro platelet functions were normal. Platelet satellitism is an in vitro phenomenon, the cause of which is unknown. We are unable to relate it to functional abnormalitles of the blood, the clinical condition of the patient, or to drugs. This phenomenon has some clinical importance in that it causes spurious thrombocytopenia.

scholarly journals Protective Effect of Post-Ischaemic Viral Delivery of Heat Shock Proteins in vivo

2008 ◽  
Vol 29 (2) ◽  
pp. 254-263 ◽  
Author(s):  
Romina A Badin ◽  
Michael Modo ◽  
Mike Cheetham ◽  
David L Thomas ◽  
David G Gadian ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heat Shock Proteins ◽  
Viral Vector ◽  
Lesion Size ◽  
In Vivo Studies ◽  
Current Evidence ◽  
Time Points ◽  
Shock Proteins

Heat shock proteins (HSPs) function as molecular chaperones involved in protein folding, transport and degradation and, in addition, they can promote cell survival both in vitro and in vivo after a range of stresses. Although some in vivo studies have suggested that HSP27 and HSP70 can be neuroprotective, current evidence is limited, particularly when HSPs have been delivered after an insult. The effect of overexpressing HSPs after transient occlusion of the middle cerebral artery in rats was investigated by delivering an attenuated herpes simplex viral vector (HSV-1) engineered to express HSP27 or HSP70 30 mins after tissue reperfusion. Magnetic resonance imaging scans were used to determine lesion size and cerebral blood flow at six different time points up to 1 month after stroke. Animals underwent two sensorimotor tests at the same time points to assess the relationship between lesion size and function. Results indicate that post-ischaemic viral delivery of HSP27, but not of HSP70, caused a statistically significant reduction in lesion size and induced a significant behavioural improvement compared with controls. This is the first evidence of effective post-ischaemic gene therapy with a viral vector expressing HSP27 in an experimental model of stroke.

scholarly journals Environmental Modulation of Oral Treponeme Virulence in a Murine Model

1999 ◽  
Vol 67 (6) ◽  
pp. 2783-2789 ◽  
Author(s):  
Lakshmyya Kesavalu ◽  
Stanley C. Holt ◽  
Jeffrey L. Ebersole
Keyword(s):  
Lesion Size ◽  
In Vivo Studies ◽  
Iron Availability ◽  
Environmental Alteration ◽  
Induction Kinetics ◽  
Focus Of Infection ◽  
Systemic Manifestations

ABSTRACT This investigation examined the effects of environmental alteration on the virulence of the oral treponemes Treponema denticolaand Treponema pectinovorum. The environmental effects were assessed by using a model of localized inflammatory abscesses in mice. In vitro growth of T. denticola and T. pectinovorum as a function of modification of the cysteine concentration significantly enhanced abscess formation and size. In contrast, growth of T. denticola or T. pectinovorum under iron-limiting conditions (e.g., dipyridyl chelation) had no effect on abscess induction in comparison to that when the strains were grown under normal iron conditions. In vivo modulation of the microenvironment at the focus of infection with Cytodex beads demonstrated that increasing the local inflammation had no effect on lesion induction or size. In vivo studies involved the determination of the effects of increased systemic iron availability (e.g., iron dextran or phenylhydrazine) on the induction, kinetics, and size of lesions. T. denticola induced significantly larger lesions in mice with iron pretreatment and demonstrated systemic manifestations of the infectious challenge and an accompanying spreading lesion with phenylhydrazine pretreatment (e.g., increases in circulating free hemoglobin). In contrast, T. pectinovorum virulence was minimally affected by this in vivo treatment to increase iron availability. T. denticolavirulence, as evaluated by lesion size, was increased additively by in vivo iron availability, and cysteine modified growth of the microorganism. Additionally, galactosamine sensitized mice to a lethal outcome following infection with both T. denticola andT. pectinovorum, suggesting an endotoxin-like activity in these treponemes. These findings demonstrated the ability to modify the virulence capacity of T. denticola andT. pectinovorum by environmental conditions which can be evaluated by using in vivo murine models.

Intraerythrocytic schizogony of Theileria annulata

Parasitology ◽  
1985 ◽  
Vol 91 (1) ◽  
pp. 67-82 ◽  
Author(s):  
P. A. Conrad ◽  
B. G. Kelly ◽  
C. G. D. Brown
Keyword(s):  
Theileria Annulata ◽  
Infected Cattle ◽  
Electron Microscopic ◽  
Trophozoite Stage ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Microscopic Studies ◽  
Food Vacuoles

The intraerythrocytic multiplication of two strains of Theileria annulata was studied with parasites maintained in stationary cultures and in the blood of infected cattle. In cultures established with blood from infected cattle 20–60% of single T. annulata piroplasms divided into quadruplet forms by day 6 in vitro. Transmission electron microscopic studies of T. annulata in culture showed that piroplasms possess intracytoplasmic food vacuoles and cytostomes during a pre-division trophozoite stage. The onset of intraerythrocytic multi plication was marked by the appearance of rhoptries and electron-dense plaques beneath the parasite's plasmalemmal membrane. The plaques developed into short segments of subplasmalemmal double membranes which were closely associated with the rhoptries. It was concluded that multiplication of T. annulata in erythrocytes occurred by schizogony, as nuclear division preceded cytoplasmic division and the final separation of merozoites. The four merozoites produced by intraerythrocytic schizogony had the same ultrastructural features as the T. annulata merozoites produced by intralymphocytic schizogony. Clusters of four merozoites, identical to those observed in stationary cultures, were also seen in the erythrocytes of persistently infected cattle and appeared to represent the most significant dividing forms of T. annulata in vivo.

scholarly journals Formation of membrane lattice structures and their specific interactions with surfactant protein A

1999 ◽  
Vol 276 (4) ◽  
pp. L642-L649 ◽  
Author(s):  
Nades Palaniyar ◽  
Ross A. Ridsdale ◽  
Stephen A. Hearn ◽  
Fred Possmayer ◽  
George Harauz
Keyword(s):  
Lipid Bilayers ◽  
Protein A ◽  
Lipid Vesicles ◽  
Surfactant Protein ◽  
Uranyl Acetate ◽  
Electron Microscopic ◽  
Membranous Structure ◽  
Microscopic Studies

Biological membranes exist in many forms, one of which is known as tubular myelin (TM). This pulmonary surfactant membranous structure contains elongated tubes that form square lattices. To understand the interaction of surfactant protein (SP) A and various lipids commonly found in TM, we undertook a series of transmission-electron-microscopic studies using purified SP-A and lipid vesicles made in vitro and also native surfactant from bovine lung. Specimens from in vitro experiments were negatively stained with 2% uranyl acetate, whereas fixed native surfactant was delipidated, embedded, and sectioned. We found that dipalmitoylphosphatidylcholine-egg phosphatidylcholine (1:1 wt/wt) bilayers formed corrugations, folds, and predominantly 47-nm-square latticelike structures. SP-A specifically interacted with these lipid bilayers and folds. We visualized other proteolipid structures that could act as intermediates for reorganizing lipids and SP-As. Such a reorganization could lead to the localization of SP-A in the lattice corners and could explain, in part, the formation of TM-like structures in vivo.

scholarly journals SAT-LB61 METTL3 Promotes Sparsely Granulated GH-Secreting Pituitary Adenomas to Behavior as Densely Granulated Adenomas

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Xiaobing Jiang ◽  
piaopiao bian ◽  
weiyu zhang
Keyword(s):  
Tumor Suppressor ◽  
Pituitary Adenomas ◽  
Somatostatin Analogues ◽  
Gh3 Cells ◽  
Messenger Rnas ◽  
Electron Microscopic ◽  
Microscopic Studies

Abstract Background: Growth hormone (GH)-secreting pituitary adenomas can be divided into densely and sparsely granulated subtypes, based on electron microscopic studies. The latter are frequently associated with more invasive behavior, and respond worse to somatostatin analogues. The underlining mechanisms are largely unknown. Increasing evidence showed that N6-methyladenosine (m6A) of messenger RNAs (mRNAs) participated in the development of various tumors. We aimed to investigate the role of RNA m6A modification in the classification of GH-secreting pituitary adenomas. Methods: The main components of m6A methyltransferase complex, demethylase, and RNA m6A levels were compared between sparsely and densely GH-secreting tumors. The role of METTL3 was functionally studied. Results: The level of m6A methyltransferases (METTL3, WTAP and METTL14) and demethylase (FTO and ALKBH5) were significantly downregulated in GH adenomas, comparing to the normal pituitary tissues. However, only METTL3 and METTL14 were shown to significantly higher in densely granulated tumors than those in sparsely ones. Consistently, the level of RNA m6A was markedly increased in densely granulated GH adenomas. In addition, the expression of METTL3 was positively correlated with the level of RNA m6A among tumor samples, and METTL3 silencing decreased RNA m6A of GH3 cells. METTL3 was demonstrated to function as a tumor suppressor based on in vivo and in vitro evidence, using patient-derived and GH3 cells. Moreover, the sensitivity of GH3 cells to pasireotide was increased with METTL3 overexpression, but decreased when METTL3 was silenced. Consistently, METTL3 silencing inhibited GH secretory, and decreased the expression of SSTR2 and SSTR5. Conclusions: METTL3 functions as a tumor suppressor in GH secreting adenomas, and enhance tumor cells sensitivity to medical treatment. Our work uncovers the critical roles of METTL3 in the pathogenesis of GH adenomas, since it potentially promotes the transition from sparsely to densely granulated subtypes.

Exploring the therapeutic potential of atorvastatin against Gram-positive and Gram-negative bacteria: In-silico, In-vitro and In- vivo evidence

2019 ◽  
Vol 19 ◽  
Author(s):  
Kamal Sethi ◽  
Arti Singh ◽  
Anoop Kumar
Keyword(s):  
Mtt Assay ◽  
In Silico ◽  
Bacterial Infections ◽  
Therapeutic Potential ◽  
In Vivo Studies ◽  
Bacterial Strains ◽  
Study Results ◽  
Reference Ligand

The incidences of opportunistic bacterial infections have increased from the past two decades or threaten to increase in the near future. Inspite of the availability of various classes of antibiotics, bacterial infections are not handled properly.Thus, in the present study, we have repurposed atorvastatin against various types of bacterial strains by using in-silico, in-vitro, and in-vivo studies. Further, preliminary safety study was conducted using MTT assay. In-silico study results have revealed that atorvastatin hasgood interaction with various targets of bacterial cell as that of reference ligand. However, under in-vitro conditions, we have foundthat atorvastatin was effective at higher concentration(>128 μg/ml) against various bacterial strains. Thus, further, atorvastatin was tested in combination with standard antibiotics and has shown synergistic effect. The MTT assay results have revealed non-cytotoxic activity of atorvastatin. In conclusion, atorvastatin in combination with standard drugs could be developed as an antibacterial agent.

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