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Journal of Neurochemistry Jul 2024A growth cone is a highly motile tip of an extending axon that is crucial for neural network formation. Three-dimensional-structured illumination microscopy, a type of...
A growth cone is a highly motile tip of an extending axon that is crucial for neural network formation. Three-dimensional-structured illumination microscopy, a type of super-resolution light microscopy with a resolution that overcomes the optical diffraction limitation (ca. 200 nm) of conventional light microscopy, is well suited for studying the molecular dynamics of intracellular events. Using this technique, we discovered a novel type of filopodia distributed along the z-axis ("z-filopodia") within the growth cone. Z-filopodia were typically oriented in the direction of axon growth, not attached to the substratum, protruded spontaneously without microtubule invasion, and had a lifetime that was considerably shorter than that of conventional filopodia. Z-filopodia formation and dynamics were regulated by actin-regulatory proteins, such as vasodilator-stimulated phosphoprotein, fascin, and cofilin. Chromophore-assisted laser inactivation of cofilin induced the rapid turnover of z-filopodia. An axon guidance receptor, neuropilin-1, was concentrated in z-filopodia and was transported together with them, whereas its ligand, semaphorin-3A, was selectively bound to them. Membrane domains associated with z-filopodia were also specialized and resembled those of lipid rafts, and their behaviors were closely related to those of neuropilin-1. The results suggest that z-filopodia have unique turnover properties, and unlike xy-filopodia, do not function as force-generating structures for axon extension.
PubMed: 38946488
DOI: 10.1111/jnc.16162 -
Annals of Coloproctology Jun 2024Neoadjuvant imatinib treatment, followed by complete transvaginal removal, presents a feasible option for large rectal gastrointestinal tumors located on the anterior...
Neoadjuvant imatinib treatment, followed by complete transvaginal removal, presents a feasible option for large rectal gastrointestinal tumors located on the anterior wall of the rectum and protruding into the vagina. The use of Martius flap interposition is convenient and can be employed to prevent rectovaginal fistula.
PubMed: 38946097
DOI: 10.3393/ac.2023.00556.0079 -
The American Journal of Surgical... Jul 2024A type of cholangiocarcinoma (CCA) characterized by peculiar histologic patterns and underlying adenofibromatous lesions has been reported in the literature mostly as...
A type of cholangiocarcinoma (CCA) characterized by peculiar histologic patterns and underlying adenofibromatous lesions has been reported in the literature mostly as individual case reports. This study aims to further clarify the defining characteristics of this spectrum of lesions. Clinicopathologic analysis of 8 biliary tumors with tubulocystic architecture arising in the background of adenofibroma-type lesions was performed. Three of these were also investigated with next-generation sequencing with a 174 genes panel. The patients were 5 males and 3 females, with a mean age of 64.6. All tumors were intrahepatic except for one perihilar that protruded into soft tissues. The mean size was 4.4 cm. At histology, all cases showed a peculiar and cytologically bland tubulocystic pattern that closely resembled tubulocystic-type kidney cancers, including back-to-back microcystic units that formed relatively demarcated nodules, and occurring in the background of adenofibromatous lesions. One case showed perineural invasion by otherwise deceptively benign-appearing microcystic structures, one had areas transitioning to intraductal tubulopapillary neoplasm, and 3 cases harbored more conventional small-duct CCA foci. In those 3 cases, both the tubulocystic and conventional CCA components were investigated by next-generation sequencing separately, and they shared the molecular alterations, including recurrent mutations in chromatin remodeling genes, such as ARID1A, BAP1, and PBRM1, and the actionable FGFR2-MCU fusion gene. In the limited follow-up, all but one were alive and free of disease after surgical resection. In conclusion, we described a distinct entity of CCA with specific histo-molecular features, for which we propose the designation of tubulocystic carcinoma of bile ducts.
PubMed: 38946053
DOI: 10.1097/PAS.0000000000002278 -
Case Reports in Otolaryngology 2024Absence or aplasia of the major salivary glands is an uncommon diagnosis and is often associated with other congenital abnormalities. Agenesis of a single submandibular...
BACKGROUND
Absence or aplasia of the major salivary glands is an uncommon diagnosis and is often associated with other congenital abnormalities. Agenesis of a single submandibular gland, however, is an even more rare phenomenon and can be associated with hypertrophy of other salivary glands.
METHODS
A 48-year-old female presented to the clinic with a left-sided neck mass below her mandible. Workup including a CT scan showed an absent left-sided submandibular gland and an enlarged sublingual gland protruding through the mylohyoid muscle.
RESULTS
The patient underwent a transoral resection of the mass with subsequent resolution of the mass. The pathology returned as normal salivary gland tissue.
CONCLUSIONS
Sublingual gland hypertrophy is a very uncommon presentation for a patient with a neck mass. This situation can arise in the setting of submandibular gland aplasia and compensatory hypertrophy of other salivary glands.
PubMed: 38939733
DOI: 10.1155/2024/8610465 -
Macromolecular Bioscience Jun 2024When a tooth is diseased or damaged through caries, bioactive molecules are liberated from the pulp and dentin as part of the natural response to injury and these are...
When a tooth is diseased or damaged through caries, bioactive molecules are liberated from the pulp and dentin as part of the natural response to injury and these are key molecules for stimulating stem cell responses for tissue repair. Incorporation of these extracellular matrix (ECM) derived molecules into a hydrogel model can mimic in vivo conditions to enable dentin-pulp complex regeneration. In this study, a chitosan/alginate (C/A) hydrogel was developed to sequester bovine ECM extracts. Human dental pulp cells (hDPCs) were cultured with these constructs and proliferation and cytotoxicity assays confirmed that these C/A hydrogels were bioactive. Sequential z-axis fluorescent imaging visualized hDPCs protruding into the hydrogel as it degraded. Alizarin red S staining showed hDPCs cultured with the hydrogels displayed increased calcium ion deposition, with dentin ECM stimulating the highest levels. Alkaline phosphatase activity was increased, as was expression of transforming growth factor-beta (TGF-β) as demonstrated using immunocytochemistry. Directional analysis following phase contrast kinetic image capture demonstrated that both dentin and pulp ECM molecules acted as chemoattractants for hDPCs. Data from this study demonstrated that purified ECM from dental pulp and dentin when delivered in a C/A hydrogel stimulated dental tissue repair processes in vitro. This article is protected by copyright. All rights reserved.
PubMed: 38938070
DOI: 10.1002/mabi.202400254 -
Parasitology International Jun 2024A new genus, Cordicestus, is proposed to accommodate proteocephalid tapeworms parasitising gars (Lepisosteiformes: Lepisosteidae) in North and Central America that were...
A new genus, Cordicestus, is proposed to accommodate proteocephalid tapeworms parasitising gars (Lepisosteiformes: Lepisosteidae) in North and Central America that were previously placed in the polyphyletic genus Proteocephalus Weinland, 1858. The new genus differs from other proteocephalid genera by the particular morphology of the scolex, which is small, protrudes apically but has no apical organ, and bears flat, heart-shaped (= cordis) suckers. In addition, the species of the new genus have an elongated cirrus sac with an almost straight internal vas deferens, and wide, sinuous ventral osmoregulatory canals with secondary canals directed outwards. The type species of the new genus, Cordicestus singularis (La Rue, 1911) n. comb., is redescribed based on new material from the shortnose gar, Lepisosteus platostomus Rafinesque (type host), and the spotted gar, L. oculatus Winchell, in the United States. Cordicestus rafaeli n. sp. is described from the tropical gar, Atractosteus tropicus Gill, in Mexico. The new species differs from its relatives primarily by the presence of craspedote proglottids (acraspedote in other species) and some biometric features. The species of Cordicestus are discussed, including unidentified specimens from A. tropicus and the Cuban gar A. tristoechus (Bloch and Schneider) in Nicaragua and Cuba, respectively, which may be new species, and a key to identification of these taxa is provided. Molecular data available for two nominal species of the new genus indicate the possible existence of another species of Cordicestus in Lepisosteus in the USA.
PubMed: 38936764
DOI: 10.1016/j.parint.2024.102916 -
Molecules (Basel, Switzerland) Jun 2024The organic molecules adsorbed on antiferromagnetic surfaces can produce interesting interface states, characterized by charge transfer mechanisms, hybridization of...
The organic molecules adsorbed on antiferromagnetic surfaces can produce interesting interface states, characterized by charge transfer mechanisms, hybridization of molecular-substrate orbitals, as well as magnetic couplings. Here, we apply an ab initio approach to study the adsorption of Fe phthalocyanine on stoichiometric CrO(0001). The molecule binds via a bidentate configuration forming bonds between two opposite imide N atoms and two protruding Cr ones, making this preferred over the various possible adsorption structures. In addition to the local modifications at these sites, the electronic structure of the molecule is weakly influenced. The magnetic structure of the surface Cr atoms shows a moderate influence of molecule adsorption, not limited to the atoms in the close proximity of the molecule. Upon optical excitation at the onset, electron density moves toward the molecule, enhancing the ground state charge transfer. We investigate this movement of charge as a mechanism at the base of light-induced modifications of the magnetic structure at the interface.
PubMed: 38930954
DOI: 10.3390/molecules29122889 -
Annals of Surgical Oncology Jun 2024Surgery is the only curative treatment for retrohepatic inferior vena cava (r-IVC) leiomyosarcoma. Cavo-hepatic confluence invasion is a poor prognostic situation,...
Ex Situ Liver Resection and Autotransplantation with Retrohepatic Inferior Vena Cava Reconstruction and Atrial Thrombectomy Under Extracorporeal Circulation for Inferior Vena Cava Leiomyosarcoma.
BACKGROUND
Surgery is the only curative treatment for retrohepatic inferior vena cava (r-IVC) leiomyosarcoma. Cavo-hepatic confluence invasion is a poor prognostic situation, requiring extreme liver surgery for selected patients to achieve R margins (a crucial prognostic factor). Ex situ liver resection and autotransplantation (ELRA), developed by Pichlmayr et al., permits to achieve such R margin. METHODS: An 84-year-old patient in excellent condition (ECOG 0), without relevant past medical history, was referred for abdominal mass, bilateral lower limbs edema, and dyspnea. Workup revealed a large r-IVC leiomyosarcoma invading cavo-hepatic confluence and protruding in right atrium without any metastasis. After multidisciplinary consultation, surgical treatment was retained. Preoperative transoesophaegal echocardiography confirmed a 4-cm protruding tumoral thrombus in right atrium without abdominalisation possibility.
RESULTS
A sterno-laparotomy was performed, consisting of a right nephrectomy for exposure and en bloc total hepatectomy comprising r-IVC after atriotomy for intracardiac thrombectomy under extracorporeal circulation. Tumorectomy (rIVC + segment I and IX) was performed on back table followed by a r-IVC reconstruction through a tubulized homologous venous patch. Native IVC was reconstructed as well, permitting a side-to-side cavo-caval anastomosis for liver reimplantation. Postoperative evolution was eventless except for an early bile leak that required surgical exploration. The patient was discharged on postoperative day 32. Pathological examination confirmed r-IVC-leiomyosarcoma TNM R, FNCLCC grade 2. Eight months after surgery, general status was conserved with disappearance of symptoms, and IVC was permeable without leiomyosarcoma recurrence.
CONCLUSION
Ex situ liver resection and autotransplantation with atrial thrombectomy is a surgical possibility for R r-IVC leiomyosarcoma invading cavo-hepatic confluence in selected patients.
PubMed: 38926212
DOI: 10.1245/s10434-024-15622-0 -
Insects Jun 2024The abundance of insects in Burmese amber illustrates a highly diverse insect community from the mid-Cretaceous period; yet, records of crickets (Grylloidea) are notably...
The abundance of insects in Burmese amber illustrates a highly diverse insect community from the mid-Cretaceous period; yet, records of crickets (Grylloidea) are notably scarce. In this study, we describe two new genera with three new species, gen. et sp. nov., sp. nov., and gen. et sp. nov., based on three specimens collected in north Myanmar. These new species can be placed within the Trigonidiidae (Orthoptera: Grylloidea) by their triangular head, compound eyes that protrude in dorsal view, and a body entirely covered with robust setae, particularly noticeable in the head and pronotum; however, subfamily assignments are not possible. Another known species, , Xu et al., 2020, from Myanmar amber is redescribed based on a new specimen and a recheck of the holotype.
PubMed: 38921157
DOI: 10.3390/insects15060442 -
Cells Jun 2024The primary cilium, an antenna-like sensory organelle that protrudes from the surface of most eukaryotic cell types, has become a signaling hub of growing interest given...
The primary cilium, an antenna-like sensory organelle that protrudes from the surface of most eukaryotic cell types, has become a signaling hub of growing interest given that defects in its structure and/or function are associated with human diseases and syndromes, known as ciliopathies. With the continuously expanding role of primary cilia in health and diseases, identifying new players in ciliogenesis will lead to a better understanding of the function of this organelle. It has been shown that the primary cilium shares similarities with the immune synapse, a highly organized structure at the interface between an antigen-presenting or target cell and a lymphocyte. Studies have demonstrated a role for known cilia regulators in immune synapse formation. However, whether immune synapse regulators modulate ciliogenesis remains elusive. Here, we find that programmed death ligand 1 (PD-L1), an immune checkpoint protein and regulator of immune synapse formation, plays a role in the regulation of ciliogenesis. We found that PD-L1 is enriched at the centrosome/basal body and Golgi apparatus of ciliated cells and depleting PD-L1 enhanced ciliogenesis and increased the accumulation of ciliary membrane trafficking proteins Rab8a, BBS5, and sensory receptor protein PC-2. Moreover, PD-L1 formed a complex with BBS5 and PC-2. In addition, we found that depletion of PD-L1 resulted in the ciliary accumulation of Gli3 and the downregulation of Gli1. Our results suggest that PD-L1 is a new player in ciliogenesis, contributing to PC-2-mediated sensory signaling and the Hh signaling cascade.
Topics: Cilia; B7-H1 Antigen; Hedgehog Proteins; Signal Transduction; Humans; Animals; Mice; Centrosome; Golgi Apparatus
PubMed: 38920633
DOI: 10.3390/cells13121003