scholarly journals The biology and evolution of polyspermy: insights from cellular and functional studies of sperm and centrosomal behavior in the fertilized egg

Reproduction ◽  
2011 ◽  
Vol 142 (6) ◽  
pp. 779-792 ◽  
Author(s):  
Rhonda R Snook ◽  
David J Hosken ◽  
Timothy L Karr
Keyword(s):  
Adverse Effect ◽  
Reproductive Biology ◽  
Microtubule Dynamics ◽  
Taxonomic Distribution ◽  
Functional Studies ◽  
Fitness Consequences ◽  
Fertilized Egg ◽  
Apparent Adverse Effect

Recent studies of centrosome biogenesis, microtubule dynamics, and their management point to their role in mediating conditions such as aging and cancer. Centrosome dysfunction is also a hallmark of pathological polyspermy. Polyspermy occurs when the oocyte is penetrated by more than one sperm and can be pathological because an excess of centrosomes compromises development. However, in some taxa, multiple sperm enter the egg with no apparent adverse effect on zygote viability. Thus, some taxa can manage excess centrosomes and represent cases of non-pathological polyspermy. While these two forms of polyspermy have long been known, we argue that there is limited understanding of the proximate and ultimate processes that underlie this taxonomic variation in the outcome of polyspermy and that studying this variation could help uncover the control and role(s) of centrosomes during fertilization in particular, but also mitosis in general. To encourage such studies we: 1) describe taxonomic differences in the outcome of polyspermy, 2) discuss mechanistic aspects of reproductive biology that may contribute to the different consequences of polyspermy, and 3) outline the potential selective events that could lead to the evolution of variation in polyspermy outcomes. We suggest that novel insights into centrosome biology may occur by cooperative studies between reproductive and evolutionary biologists focusing on the mechanisms generating variation in the fitness consequences of polyspermy, and in the taxonomic distribution of all these events. The consequent discoveries of these studies may lead to informative insights into cancer and aging along with other centrosome-related diseases and syndromes.

Furosemide Abuse Without Apparent Adverse Effect

JAMA ◽  
1976 ◽  
Vol 235 (2) ◽  
pp. 146 ◽  
Author(s):  
Elliot J. Howard
Keyword(s):  
Adverse Effect ◽  
Apparent Adverse Effect

Endophytic Fungi as a reservoir of Lignocellulolytic Enzymes- A Review

2021 ◽  
Vol 16 (11) ◽  
pp. 134-140
Author(s):  
Ram Kumar Pundir ◽  
Pranay Jain
Keyword(s):  
Adverse Effect ◽  
Natural Products ◽  
Enzymatic Activity ◽  
Endophytic Fungi ◽  
Present Status ◽  
Lignocellulolytic Enzymes ◽  
Agricultural Industries ◽  
Potential Use ◽  
Apparent Adverse Effect

The potential use of microorganisms as biotechnological sources of industrially important enzymes has stimulated interest in exploration of extracellular enzymatic activity in several microorganisms. Endophytic fungi are those fungi which colonize plants internally without apparent adverse effect. Endophytic fungi are relatively unexplored producers of metabolites useful to pharmaceutical and agricultural industries. As a result, the role of endophytes in production of various natural products with greater bioactivity has received increased attention. Endophytic fungi have been found to degrade lignocellulose consisting of lignin, cellulose and hemicellulose with the aid of lignocellulases enzynes. This review highlights the potential of endophytic fungi for production of lignocellulases and also discusses the present status and future prospectives in this field.

Letter: Furosemide abuse without apparent adverse effect

JAMA ◽  
1976 ◽  
Vol 235 (2) ◽  
pp. 146b-146 ◽  
Author(s):  
E. J. Howard
Keyword(s):  
Adverse Effect ◽  
Apparent Adverse Effect

scholarly journals THE EFFECT OF CHLORDANE AND THIRAM ON DAMPING-OFF AND SEEDLING GROWTH

1961 ◽  
Vol 37 (3) ◽  
pp. 211-216 ◽  
Author(s):  
J. Cockerill
Keyword(s):  
Adverse Effect ◽  
Seedling Growth ◽  
Root Development ◽  
Red Pine ◽  
Damping Off ◽  
White Grub ◽  
Seedling Mortality ◽  
Apparent Adverse Effect

Chlordane, applied to seed beds of red pine to control white grub infestation, increased seedling mortality due to damping-off in these beds. Losses were significantly reduced when the seed was pelleted with thiram prior to sowing. Neither chlordane nor thiram, alone or in combination, had any apparent adverse effect on seedling growth, root development, or the formation of mycorrhiza.

Minocycline-induced blue sclera and skin hyperpigmentation

2021 ◽  
Vol 14 (11) ◽  
pp. e245508
Author(s):  
Stacey Law
Keyword(s):  
Adverse Effect ◽  
Literature Search ◽  
Lower Limbs ◽  
Skin Hyperpigmentation ◽  
Ocular Structure ◽  
Causative Agents ◽  
Blue Sclera ◽  
Apparent Adverse Effect ◽  
Scleral Pigmentation

A 73-year-old man presented to the emergency department with lethargy and influenza-like symptoms. Incidentally, prominent blue sclera and blue-grey skin discolouration to the periorbital skin, pinnae, neck, upper and lower limbs, hands, feet, fingernails and toenails were noted. His general practitioner (GP) had previously ceased amiodarone, believing it to be the causative agent. A literature search confirms the side effects were likely due to minocycline, which the patient had been taking for 10 years. Long-term minocycline use is associated with scleral and skin hyperpigmentation, with no apparent adverse effect on ocular structure or function. The pigmentation may reverse with cessation of minocycline, or it may be permanent. Amiodarone may also cause skin hyperpigmentation, but scleral pigmentation is not a known association. This case report explores the side effect profiles of these two drugs, and highlights the potential for confusion regarding causative agents when used concurrently.

Repeated Naloxone Administration for Morphine Overdose in a 1-Month-Old Infant

PEDIATRICS ◽  
1979 ◽  
Vol 63 (4) ◽  
pp. 606-608
Author(s):  
Alan E. Gober ◽  
Gregory L. Kearns ◽  
Robert A. Yokel ◽  
Larry Danziger
Keyword(s):  
Adverse Effect ◽  
Cumulative Dose ◽  
Narcotic Antagonist ◽  
Naloxone Administration ◽  
Naloxone Hydrochloride ◽  
Apparent Adverse Effect

Repeated injections of naloxone hydrochloride, a pure narcotic antagonist, were administered to a 3,320-gm 4-week-old boy for treatment of an accidental morphine overdose. The infant received frequent naloxone hydrochloride injections (0.2 mg per injection) during the first 12 hours of therapy to reverse morphine-induced apnea, hypothermia, and flaccidity. A cumulative dose of 2.73 mg of naloxone hydrochloride (0.822 mg/kg) was administered over 27 hours without apparent adverse effect or evidence of toxicity.

The Resolution and Contrast in Biological Sections Determined by Inelastic and Elastic Scattering

1973 ◽  
Vol 31 ◽  
pp. 224-225
Author(s):  
D. L. Misell
Keyword(s):  
Electron Microscopy ◽  
Adverse Effect ◽  
Elastic Scattering ◽  
Inelastic Scattering ◽  
Amorphous Carbon ◽  
Polymeric Materials ◽  
Chromatic Aberration ◽  
Image Resolution ◽  
Quantitative Estimates ◽  
Elastic Ratio

In the electron microscopy of biological sections the adverse effect of chromatic aberration on image resolution is well known. In this paper calculations are presented for the inelastic and elastic image intensities using a wave-optical formulation. Quantitative estimates of the deterioration in image resolution as a result of chromatic aberration are presented as an alternative to geometric calculations. The predominance of inelastic scattering in the unstained biological and polymeric materials is shown by the inelastic to elastic ratio, I/E, within an objective aperture of 0.005 rad for amorphous carbon of a thickness, t=50nm, typical of biological sections; E=200keV, I/E=16.

The low-resolution 3D-structure of porin, a channel-forming protein in E. coliouter membranes

1983 ◽  
Vol 41 ◽  
pp. 440-441
Author(s):  
A. Engel ◽  
D.L. Dorset ◽  
A. Massalski ◽  
J.P. Rosenbusch
Keyword(s):  
Crystal Packing ◽  
3D Structure ◽  
Gram Negative Bacteria ◽  
Protein Ratio ◽  
Crystal Forms ◽  
Large Molecules ◽  
Functional Studies ◽  
Voltage Dependent ◽  
Planar Membranes ◽  
Hexagonal Arrays

Porins represent a group of channel forming proteins that facilitate diffusion of small solutes across the outer membrane of Gram-negative bacteria, while excluding large molecules (>650 Da). Planar membranes reconstituted from purified matrix porin (OmpF protein) trimers and phospholipids have allowed quantitative functional studies of the voltage-dependent channels and revealed concerted activation of triplets. Under the same reconstitution conditions but using high protein concentrations porin aggregated to 2D lattices suitable for electron microscopy and image processing. Depending on the lipid-to- protein ratio three different crystal packing arrangements were observed: a large (a = 93 Å) and a small (a = 79 Å) hexagonal and a rectangular (a = 79 Å b = 139 Å) form with p3 symmetry for the hexagonal arrays. In all crystal forms distinct stain filled triplet indentations could be seen and were found to be morphologically identical within a resolution of (22 Å). It is tempting to correlate stain triplets with triple channels, but the proof of this hypothesis requires an analysis of the structure in 3 dimensions.

Ionic homeostasis and subcellular element compartmentation

1990 ◽  
Vol 48 (2) ◽  
pp. 150-151
Author(s):  
Ann LeFurgey ◽  
Peter Ingram ◽  
J.J. Blum ◽  
M.C. Carney ◽  
L.A. Hawkey ◽  
...  
Keyword(s):  
Leishmania Major ◽  
Ionic Homeostasis ◽  
X Ray ◽  
Functional Studies ◽  
Cell Compartments ◽  
X Ray Imaging ◽  
Resolution Electron ◽  
Multiple Cell ◽  
Role Of Zn

Subcellular compartments commonly identified and analyzed by high resolution electron probe x-ray microanalysis (EPXMA) include mitochondria, cytoplasm and endoplasmic or sarcoplasmic reticulum. These organelles and cell regions are of primary importance in regulation of cell ionic homeostasis. Correlative structural-functional studies, based on the static probe method of EPXMA combined with biochemical and electrophysiological techniques, have focused on the role of these organelles, for example, in maintaining cell calcium homeostasis or in control of excitation-contraction coupling. New methods of real time quantitative x-ray imaging permit simultaneous examination of multiple cell compartments, especially those areas for which both membrane transport properties and element content are less well defined, e.g. nuclei including euchromatin and heterochromatin, lysosomes, mucous granules, storage vacuoles, microvilli. Investigations currently in progress have examined the role of Zn-containing polyphosphate vacuoles in the metabolism of Leishmania major, the distribution of Na, K, S and other elements during anoxia in kidney cell nuclel and lysosomes; the content and distribution of S and Ca in mucous granules of cystic fibrosis (CF) nasal epithelia; the uptake of cationic probes by mltochondria in cultured heart ceils; and the junctional sarcoplasmic retlculum (JSR) in frog skeletal muscle.

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