Clinical, imaginological and pathological aspects of umbilical panvasculitis in calves: case report

The diagnosis of umbilical infections in neonates can be obtained from clinical signs, but the intracavitary involvement of structures and associated complications can be underestimated, compromising the establishment of adequate therapeutic approaches or prognosis. This case report presents the clinical, imaging, pathological and microbiological aspects of an umbilical infection in calves. Physical examination of the animal identified apathy, low body score, increased volume in the umbilical region and joints. The abdominal palpation identified firm structures in topography of the arteries and umbilical vein. Imaging examinations of the abdomen and joints were performed. Multiple, hyperechogenic focal structures have been identified in the liver, as well as cylindrical and firm structures in topography of the arteries and umbilical vein. In the joints, osteolytic changes, periosteal reactions, subchondral sclerosis and formation of osteophytes were seen. Umbilical panvasculitis triggered arthritis and an infectious process in the liver, the case being assessed as having an unfavorable prognosis and the animal being referred for euthanasia. At necropsy, multifocal abscesses were observed in the pleura, ribs, omentum, spleen and liver. There was granulomatous exudate in the urinary vesicle. The affected joints presented thickening of the joint capsule with the presence of exudate. In the microbiological analysis of liver fragments, urinary vesicle content and joint exudate, Proteus mirabilis with resistance to antimicrobials was identified. Imaging studies collaborated with the establishment of the prognosis and conduct adopted, and must, whenever possible, be included in the clinical examination. In case of death, necropsy allows a correct association of clinical signs and imaging findings.

Wing serial homologues and the diversification of insect outgrowths: insights from the pupae of scarab beetles

Modification of serially homologous structures is a common avenue towards functional innovation in developmental evolution, yet ancestral affinities among serial homologues may be obscured as structure-specific modifications accumulate over time. We sought to assess the degree of homology to wings of three types of body wall projections commonly observed in scarab beetles: (i) the dorsomedial support structures found on the second and third thoracic segments of pupae, (ii) the abdominal support structures found bilaterally in most abdominal segments of pupae, and (iii) the prothoracic horns which depending on species and sex may be restricted to pupae or also found in adults. We functionally investigated 14 genes within, as well as two genes outside, the canonical wing gene regulatory network to compare and contrast their role in the formation of each of the three presumed wing serial homologues. We found 11 of 14 wing genes to be functionally required for the proper formation of lateral and dorsal support structures, respectively, and nine for the formation of prothoracic horns. At the same time, we document multiple instances of divergence in gene function across our focal structures. Collectively, our results support the hypothesis that dorsal and lateral support structures as well as prothoracic horns share a developmental origin with insect wings. Our findings suggest that the morphological and underlying gene regulatory diversification of wing serial homologues across species, life stages and segments has contributed significantly to the extraordinary diversity of arthropod appendages and outgrowths.

Seismogravitational processes accompanying the evolution of seismic focal structures in the lithosphere

Observations reflecting the structure and conditions of the seismogravitational process in the lithosphere were analyzed using the data on the catastrophic tsunamigenic earthquake of Maule (Chile) [Sobisevich et al., 2019]. Seismogravitational processes were first identified by a group of Soviet scientists from the city of Leningrad (now St. Petersburg) under the leadership of Professor E.M. Linkov [Linkov et al., 1982, 1990]. The study of these processes continues at the North Caucasus Geophysical Observatory of IPE RAS, which was established in 2004. Experiments are carried out using unique quartz tiltmeters designed by D.G. Gridnev, which ensure the stable registration of long–period seismogravitational processes on the scale of the Earth [Sobisevich, 2013; Sobisevich et al., 2017].

RAP80 and BRCA1 PARsylation protect chromosome integrity by preventing retention of BRCA1-B/C complexes in DNA repair foci

BRCA1 promotes error-free, homologous recombination-mediated repair (HRR) of DNA double-stranded breaks (DSBs). When excessive and uncontrolled, BRCA1 HRR activity promotes illegitimate recombination and genome disorder. We and others have observed that the BRCA1-associated protein RAP80 recruits BRCA1 to postdamage nuclear foci, and these chromatin structures then restrict the amplitude of BRCA1-driven HRR. What remains unclear is how this process is regulated. Here we report that both BRCA1 poly-ADP ribosylation (PARsylation) and the presence of BRCA1-bound RAP80 are critical for the normal interaction of BRCA1 with some of its partners (e.g., CtIP and BACH1) that are also known components of the aforementioned focal structures. Surprisingly, the simultaneous loss of RAP80 and failure therein of BRCA1 PARsylation results in the dysregulated accumulation in these foci of BRCA1 complexes. This in turn is associated with the intracellular development of a state of hyper-recombination and gross chromosomal disorder. Thus, physiological RAP80-BRCA1 complex formation and BRCA1 PARsylation contribute to the kinetics by which BRCA1 HRR-sustaining complexes normally concentrate in nuclear foci. These events likely contribute to aneuploidy suppression.

Dynein–Dynactin–NuMA clusters generate cortical spindle-pulling forces as a multi-arm ensemble

To position the mitotic spindle within the cell, dynamic plus ends of astral microtubules are pulled by membrane-associated cortical force-generating machinery. However, in contrast to the chromosome-bound kinetochore structure, how the diffusion-prone cortical machinery is organized to generate large spindle-pulling forces remains poorly understood. Here, we develop a light-induced reconstitution system in human cells. We find that induced cortical targeting of NuMA, but not dynein, is sufficient for spindle pulling. This spindle-pulling activity requires dynein-dynactin recruitment by NuMA’s N-terminal long arm, dynein-based astral microtubule gliding, and NuMA’s direct microtubule-binding activities. Importantly, we demonstrate that cortical NuMA assembles specialized focal structures that cluster multiple force-generating modules to generate cooperative spindle-pulling forces. This clustering activity of NuMA is required for spindle positioning, but not for spindle-pole focusing. We propose that cortical Dynein-Dynactin-NuMA (DDN) clusters act as the core force-generating machinery that organizes a multi-arm ensemble reminiscent of the kinetochore.

Optogenetic reconstitution reveals that Dynein-Dynactin-NuMA clusters generate cortical spindle-pulling forces as a multi-arm ensemble

To position the mitotic spindle within the cell, dynamic plus ends of astral microtubules are pulled by membrane-associated cortical force-generating machinery. However, in contrast to the chromosome-bound kinetochore structure, how the diffusion-prone cortical machinery is organized to generate large spindle-pulling forces remains poorly understood. Here, we develop a light-induced reconstitution system in human cells. We find that induced cortical targeting of NuMA, but not dynein, is sufficient for spindle pulling. This spindle-pulling activity requires dynein-dynactin recruitment/activation by NuMA’s N-terminal long arm, and NuMA’s direct microtubule-binding activities to achieve a multiplicity of microtubule interactions. Importantly, we demonstrate that cortical NuMA assembles specialized focal structures that cluster multiple force-generating modules to generate cooperative spindle-pulling forces. This clustering activity of NuMA is required for spindle positioning, but not for spindle-pole focusing. We propose that cortical Dynein-Dynactin-NuMA (DDN) clusters act as the core force-generating machinery that organizes a multi-arm ensemble reminiscent of the kinetochore.

Time Reversal Processing Effect on Foci Structure in a Dynamic Ocean Waveguide

Time-reversal mirror (TRM) was recently developed for underwater communication system application. This technique has been introduced as an approach to compensate for signal distortion due to multiple path effect in ocean waveguide. TRM is used in this paper for sending a message signal in ocean waveguide, received at time-reversal-array (TRA), and retransmitted to the dynamic ocean environment with an internal solitary wave. The focal structures obtained from different simulating cases are used for bidirectional transmission expediency, and the TRA is used as the relay-line or trunked radio. Ocean waveguide characteristic effects on acoustical properties are also shown in this paper, and focal structure in different ocean environments is analyzed to provide an optimal approach to underwater communication systems and for physical insight's interests.