scholarly journals A refutation to 'A new A-P compartment boundary and organizer in holometabolous insect wings.'

2018 ◽  
Author(s):  
Peter A. Lawrence ◽  
Jose Casal ◽  
Jose F. de Celis ◽  
Gines Morata
Keyword(s):  
Internal Controls ◽  
The Other ◽  
Butterfly Wing ◽  
Posterior Compartment ◽  
Wing Vein ◽  
Present Evidence ◽  
Holometabolous Insect ◽  
Insect Wings ◽  
Compartment Boundary ◽  
Dorsoventral Boundary

We respond to a recent report by Abbasi and Marcus who present two main findings: first they argue that there is an organiser and a compartment boundary within the posterior compartment of the butterfly wing. Second, they present evidence for a previously undiscovered lineage boundary near wing vein 5 in Drosophila, a boundary that delineates a "far posterior" compartment. Clones of cells were marked with the yellow mutation and they reported that these clones always fail to cross a line close to vein 5 on the Drosophila wing. In our hands yellow proved an unusable marker for clones in the wing blade and therefore we reexamined the matter. We marked clones of cells with multiple wing hairs or forked and found a substantial proportion of these clones cross the proposed lineage boundary near vein 5, in conflict with their findings and conclusion. As internal controls we showed that these same clones respect the other two well established compartment boundaries: the anteroposterior compartment boundary is always respected. The dorsoventral boundary is mostly respected, and is crossed only by clones that are induced early in development, consistent with many reports. We question the validity of Abbasi and Marcus' conclusions regarding the butterfly wing but present no new data. Arising from: R. Abbasi and J. M. Marcus Sci. Rep. 7, 16337 (2017); https://doi.org/10.1038/s41598-017-16553-5 .

scholarly journals A refutation to ‘A new A-P compartment boundary and organizer in holometabolous insect wings’

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Peter A. Lawrence ◽  
José Casal ◽  
José F. de Celis ◽  
Ginés Morata
Keyword(s):  
Holometabolous Insect ◽  
Insect Wings ◽  
Compartment Boundary

Regeneration from duplicating fragments of the Drosophila wing disc

Development ◽  
1981 ◽  
Vol 66 (1) ◽  
pp. 117-126
Author(s):  
Jane Karlsson ◽  
R. J. Smith
Keyword(s):  
Imaginal Disc ◽  
General Rule ◽  
Wing Disc ◽  
The Other ◽  
Posterior Compartment ◽  
Drosophila Wing ◽  
Polar Coordinate ◽  
New Type ◽  
Coordinate Model

It is a general rule that of two complementary Drosophila imaginal disc fragments, one regenerates and the other duplicates. This paper reports an investigation of an exception to this rule. Duplicating fragments from the periphery of the wing disc which lacked presumptive notum were found to regenerate notum structures during and after duplication. The propensity for this was greatest in fragments lying close to the presumptive notum, with the exception of a fragment confined to the posterior compartment, which did not regenerate notum. Structures were added sequentially, and regeneration stopped once most of the notum was present. These results are not easily explained by the polar coordinate model, which states that regeneration cannot occur from duplicating fragments. Since compartments appear to be involved in this type of regeneration as in others, it is suggested that a new type of model is required, one which permits simultaneous regeneration and duplication, and assigns a major role to compartments.

scholarly journals COVID-19: A Therapeutic Approach Based on Pathophysiological Staging

2020 ◽  
Vol 14 (1) ◽  
pp. 32-37
Author(s):  
Christian Domingo Ribas
Keyword(s):  
Respiratory Failure ◽  
Therapeutic Approach ◽  
Distress Syndrome ◽  
The Other ◽  
Present Evidence ◽  
Respiratory Events ◽  
Therapeutic Decisions ◽  
Disease Staging ◽  
The One ◽  
Rule Out

The COVID-19 pandemic is a recently emerging problem. This has caused that the knowledge of the disease has been progressive and, therefore, the therapeutic decisions have been conditioned by this lack of knowledge on the one hand and by the therapeutic limitations on the other. Many published studies are methodologically weak and their conclusions, of limited value, have contributed to creating confusion on the therapeutic approach of the disease. In the present paper, we propose a therapeutic approach based on a new disease staging. The therapeutic approach is divided into two big sections: the pharmacological treatment for the phase of viral replication, cytokine storm or late respiratory events (which includes the adult respiratory distress syndrome (ARDS)) and the treatment of the respiratory failure In every stage, we discuss the pathophysiology and comment (accept or rule out) the pharmacological options according to the present evidence. Moreover, we indicate how respiratory failure should be treated. Some characteristics are based on the evidence found in the literature. Others are the result of my experience in other situations.

Characteristics of Dynamic Forces Generated by a Flapping Butterfly and its Wake Structure

2017 ◽  
Author(s):  
Masaki Fuchiwaki ◽  
Kazuhiro Tanaka
Keyword(s):  
Flow Field ◽  
Butterfly Wing ◽  
Vortex Loop ◽  
Insect Wing ◽  
Fluid Forces ◽  
Insect Wings ◽  
Piv Measurement ◽  
Dynamic Forces ◽  
Butterfly Wings ◽  
The Relationship

A typical example of the flow field around a moving elastic body is that around butterfly wings. Butterflies fly by skillfully controlling this flow field, and vortices are generated around their bodies. The motion of their elastic wings produces dynamic fluid forces by manipulating the flow field. For this reason, there has been increased academic interest in the flow field and dynamic fluid forces produced by butterfly wings. A number of recent studies have qualitatively and quantitatively examined the flow field around insect wings. In some such previous studies, the vortex ring or vortex loop formed on the wing was visualized. However, the characteristics of dynamic forces generated by the flapping insect wing are not yet sufficiently understood. The purpose of the present study is to investigate the characteristics of dynamic lift and thrust produced by the flapping butterfly wing and the relationship between the dynamic lift and thrust and the flow field around the butterfly. We conducted the dynamic lift and thrust measurements of a fixed flapping butterfly, Idea leuconoe, using a six-axes sensor. Moreover, two-dimensional PIV measurement was conducted in the wake of the butterfly. The butterfly produced dynamic lift in downward flapping which became maximum at a flapping angle of approximately 0.0 deg. At the same time, the butterfly produced negative dynamic thrust during downward flapping. The negative dynamic thrust was not produced hydrodynamically by a flapping butterfly wing because a jet was not formed in front of the butterfly. The negative dynamic thrust was the kicking force for jumping and the maximum of this kicking force was about 6.0 times as large as the weight. On the other hand, the butterfly produced dynamic thrust in upward flapping which was approximately 6.0 times as large as the weight of the butterfly. However, the attacking force by the abdomen of the butterfly was included in the dynamic thrust and we have not yet clarified quantitatively the dynamic thrust produced by the butterfly wing.

Role of knot (kn) in Wing Patterning in Drosophila

Genetics ◽  
1997 ◽  
Vol 147 (3) ◽  
pp. 1203-1212 ◽  
Author(s):  
Katerina Nestoras ◽  
Helena Lee ◽  
Jym Mohler
Keyword(s):  
Hedgehog Signaling ◽  
Imaginal Disc ◽  
Hedgehog Signaling Pathway ◽  
Posterior Compartment ◽  
Drosophila Wing ◽  
Compartment Boundary ◽  
Hh Signaling ◽  
Embryonic Segmentation ◽  
Anterior Posterior

We have undertaken a genetic analysis of new strong alleles of knot (kn). The original kn1 mutation causes an alteration of wing patterning similar to that associated with mutations of fused (fu), an apparent fusion of veins 3 and 4 in the wing. However, unlike fu, strong kn mutations do not affect embryonic segmentation and indicate that kn is not a component of a general Hh (Hedgehog)-signaling pathway. Instead we find that kn has a specific role in those cells of the wing imaginal disc that are subject to ptc-mediated Hh-signaling. Our results suggest a model for patterning the medial portion of the Drosophila wing, whereby the separation of veins 3 and 4 is maintained by kn activation in the intervening region in response to Hh-signaling across the adjacent anterior-posterior compartment boundary.

scholarly journals Transport systems for polyamines in the established renal cell line LLC-PK1. Polarized expression of an Na+-dependent transporter

1990 ◽  
Vol 265 (2) ◽  
pp. 609-612 ◽  
Author(s):  
L Van Den Bosch ◽  
H De Smedt ◽  
L Missiaen ◽  
J B Parys ◽  
R Borghgraef
Keyword(s):  
Cell Line ◽  
Renal Cell ◽  
The Other ◽  
Transport Systems ◽  
Present Evidence ◽  
Cell Monolayers ◽  
Other Hand ◽  
Basolateral Side ◽  
Renal Cell Line ◽  
Polyamine Uptake

We present evidence for the existence of an Na(+)-dependent transporter and an Na(+)-independent transporter for polyamines in LLC-PK1 cells. Both transporters could be discriminated by their sensitivity to inhibitors, particularly rho-chloromercuriphenyl sulphate and various polycationic molecules. By using cell monolayers grown on a permeable filter support, we have found that the Na(+)-dependent polyamine uptake occurred preferentially from the basolateral side. The Na(+)-independent uptake, on the other hand, occurred to the same extent from either the apical or the basolateral side.

BIRTH ORDER AND SEXUAL ORIENTATION IN MEN: EVIDENCE FOR TWO INDEPENDENT INTERACTIONS

2005 ◽  
Vol 38 (6) ◽  
pp. 811-819 ◽  
Author(s):  
ANTHONY F. BOGAERT ◽  
JIAN LIU
Keyword(s):  
Sexual Orientation ◽  
Birth Order ◽  
Orientation Relationship ◽  
Study Data ◽  
The Other ◽  
Heterosexual Men ◽  
Parental Age ◽  
Present Evidence ◽  
Male Sexual Orientation

Birth order is correlated with male sexual orientation, but the reason(s) for this relationship is unclear. In the present study, data from a Canadian sample of homosexual and heterosexual men (N=604) were used to present evidence of two independent birth order interactions – one with height and the other with parental age – predicting sexual orientation in men. If these findings prove reliable, it raises the possibility that different aetiological factors underlie the birth order/sexual orientation relationship in men.

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