Characteristics of morphodynamic conditions in the shallows of Puck Bay (southern Baltic Sea)

Puck Bay is an unusual and thus interesting coastal water region, as it combines two different environments – a lagoon and the sea. They differ from each other in their seabed morphology, salinity, dynamics and water exchange. Their common elements are the extensive shallows and the vicinity of the Hel Peninsula. The shallows of Puck Bay have developed at various stages of its evolution, which began several thousand years ago and continues to this day. They have been shaped by varying morphogenetic factors resulting from changes in sea level and accompanying evolution phases of sand barriers, e.g. washover fans, as well as the intensity and directions of sediment transport. At present, the shallows cover more than 35% of the seabed area and are influenced by hydrodynamic factors and availability of sediments. The study area was divided into five fields, taking into account morphological and genetic criteria as well as recent hydrodynamic conditions. This study provides an updated map with classification and distribution of surface sediments and describes grain size parameters for sediment samples collected in the selected fields. Based on a comprehensive assessment of grain size parameters, lithodynamic equilibrium zones were determined and areas of sediment deposition and redeposition were identified.

Identification of a novel regulator of Clostridioides difficile cortex formation

Clostridioides difficile is a leading cause of healthcare-associated infections worldwide. C. difficile infections are transmitted by its metabolically dormant, aerotolerant spore form. Functional spore formation depends on the assembly of two protective layers: a thick layer of modified peptidoglycan known as the cortex layer and a multilayered proteinaceous meshwork known as the coat. We previously identified two spore morphogenetic proteins, SpoIVA and SipL, that are essential for recruiting coat proteins to the developing forespore and making functional spores. While SpoIVA and SipL directly interact, the identities of the proteins they recruit to the forespore remained unknown. We used mass spectrometry-based affinity proteomics to identify proteins that interact with the SpoIVA-SipL complex. These analyses identified the Peptostreptococcaceae family-specific, sporulation-induced bitopic membrane protein CD3457 (renamed SpoVQ) as a protein that interacts with SipL and SpoIVA. Loss of SpoVQ decreased heat-resistant spore formation by ∼5-fold and reduced cortex thickness∼2-fold; the thinner cortex layer of ΔspoVQ spores correlated with higher levels of spontaneous germination (i.e., in the absence of germinant). Notably, loss of SpoVQ in either spoIVA or sipL mutants prevented cortex synthesis altogether and greatly impaired the localization of a SipL-mCherry fusion protein around the forespore. Thus, SpoVQ is a novel regulator of C. difficile cortex synthesis that appears to link cortex and coat formation. The identification of SpoVQ as a spore morphogenetic protein further highlights how Peptostreptococcaceae family-specific mechanisms control spore formation in C. difficile.ImportanceThe Centers for Disease Control has designated Clostridioides difficile as an urgent threat because of its intrinsic antibiotic resistance. C. difficile persists in the presence of antibiotics in part because it makes metabolically dormant spores. While recent work has shown that preventing the formation of infectious spores can reduce C. difficile disease recurrence, more selective anti-sporulation therapies are needed. The identification of spore morphogenetic factors specific to C. difficile would facilitate the development of such therapies. In this study, we identified SpoVQ (CD3457) as a spore morphogenetic protein specific to the Peptostreptococcaceae family that regulates the formation of C. difficile’s protective spore cortex layer. SpoVQ acts in concert with the known spore coat morphogenetic factors, SpoIVA and SipL, to link formation of the protective coat and cortex layers. These data reveal a novel pathway that could be targeted to prevent the formation of infectious C. difficile spores.

Col6a1+/CD201+ mesenchymal cells regulate intestinal morphogenesis and homeostasis

Intestinal mesenchymal cells encompass multiple subsets, whose origins, functions, and pathophysiological importance are still not clear. Here, we used the Col6a1Cre mouse, which targets telocytes and perivascular cells that can be further distinguished by the combination of the CD201, PDGFRα and αSMA markers. Developmental studies revealed that the Col6a1Cre mouse also targets mesenchymal aggregates that are crucial for intestinal morphogenesis and patterning, suggesting an ontogenic relationship between them and homeostatic telocytes. Cell depletion experiments in adulthood showed that Col6a1+/CD201+ mesenchymal cells regulate homeostatic enteroendocrine cell differentiation and epithelial proliferation. During acute colitis, they expressed an inflammatory and extracellular matrix remodeling gene signature, but they also retained their properties and topology. Notably, both in homeostasis and tissue regeneration, they were dispensable for normal organ architecture, while CD34+ mesenchymal cells expanded, localised at the top of the crypts and showed increased expression of villous-associated morphogenetic factors, providing thus evidence for the plasticity potential of distinct mesenchymal populations in the intestine. Our results provide a comprehensive analysis of the identities, origin, and functional significance of distinct mesenchymal populations in the intestine.

Growth Factors in Oral Tissue Engineering: New Perspectives and Current Therapeutic Options

The present investigation is aimed at systematically analyzing the recent literature about the innovative scaffold involved in the reconstructive surgeries by applying growth factors and tissue engineering. An extensive review of the contemporary literature was conducted according to the PRISMA guidelines by accessing the PubMed, Embase, and Scopus Elsevier databases. Authors performed the English language manuscript research published from 2003 to 2020. A total of 13 relevant studies were included in the present review. The present systematic review included only papers with significant results about correlation between scaffold, molecular features of growth factor, and reconstructive surgeries in oral maxillofacial district. The initial research with filters recorded about 1023 published papers. Beyond reading and considering of suitability, only 42 and then 36 full-text papers were recorded for the revision. All the researches recorded the possibility of using growth factors on rebuilding atrophic jaws. Different growth factors like morphogenetic factors, cytokines, and inflammatory ones and their application over different scaffold materials were recorded. Further investigations should be required in order to state scientific evidence about a clear advantage of applying tissue engineering for therapeutic purpose.

The search for a new artistic image in the architecture of the Far North pavilion at the All-Russia Industrial and Art Exhibition in 1896 in Nizhny Novgorod

The Far North Pavilion was built by the Moscow-Yaroslavl-Arkhangelsk Railway Joint-Stock Company headed by S. I. Mamontov. The pavilion was supposed to draw public attention to the necessity of continuing the construction of the existing road to the North. The Far North pavilion, along with the Shukhov Tower, was one of the most conceptual structures of this exhibition, showing promising directions in the development of architecture and art, in which new principles of morphogenesis in architecture were first manifested. The article is aimed at identifying the morphogenetic factors that influenced the creation of an innovative image of the pavilion, including the history of its creation, as well as analyzing the new principles of architectural morphogenesis based on an emotional imaginative perception of the North as a source of inspiration. These principles later formed the system of artistic stylization, which determined the aesthetics of Art Nouveau in its national version.

Cicatrização de ferida cirúrgica tratada com laser de baixa intensidade: relato de caso

Os lasers de baixa potência são utilizados para fins terapêuticos e bioestimuladores, agindo principalmente como aceleradores em processos cicatriciais, além de possuírem efeitos redutores de dor e anti-inflamatórios. A cicatrização envolve fenômenos biológicos como alterações vasculares e celulares, proliferação epitelial, proliferação de fibroblastos, revascularização e contração da ferida. Em tecidos epiteliais, o laser causa a proliferação, migração de células e ativa os fatores de crescimento. Já em tecido conjuntivo, atua aumentando a síntese de colágeno por fibroblastos, além de aumentar a vascularização ao promover angiogênese. Este artigo tem por objetivo relatar um caso de exposição óssea pós-cirúrgica tratada com terapia a laser de baixa intensidade, demonstrando aspectos clínicos e teóricos, além de analisar os efeitos da laserterapia e sua importância no processo de cicatrização. Em casos de exposição óssea uma alternativa viável é a enxertia de tecido gengival. No entanto, a necessidade de dois procedimentos cirúrgicos na área doadora e da receptora pode apresentar-se como desvantagem na aplicabilidade da técnica. Considera-se que a laserterapia possibilita a regeneração com ausência de procedimentos cirúrgicos, além de promover o aumento do fluxo sanguíneo e controle de processos inflamatórios. Pode-se concluir que a laserterapia de baixa intensidade representa um auxílio no processo de cicatrização e possibilitou a resolução do caso clínico de maneira eficaz.Descritores: Lasers; Odontologia; Cicatrização.ReferênciasCavalcanti TM, Almeida-Barros RQ, Catão MHCV, Feitosa APA, Lins RDAU. Conhecimento das propriedades físicas e da interação do laser com os tecidos biológicos na odontologia. An Bras Dermatol. 2011;86(5):955-60.Saracino S, Mozzati M, Martinasso G, Poi R, Canuto RA, Muzio G. Superpulsed laser irradiation increases osteoblast activity via modulation of bone morphogenetic factors. Lasers Surg Med. 2009;41(4):298-304.Aykol G, Baser U, Maden I, Kazak Z, Onan U et al. The effect of low-level laser therapy as an adjunct to non-surgical periodontal treatment. J Periodontol. 2011;82(3):481-88.Bourguignon-Filho AM, Feitosa ACR, Beltrão GC, Pagnoncelli RM. Utilização do laser de baixa intensidade no processo de cicatrização tecidual. Revisão da literatura. Rev Port Estomatol Med Dent Cir Maxilofac. 2005;46(1):37-43.Chaves MEA, Araújo AR, Piancastelli ACC, Pinotti M. Effects of low-power light therapy on wound healing: LASER x LED. An Bras Dermatol. 2014;89(4):616-23.Assis, VKS, Cardoso FL, Silva BP. Aplicabilidade da laserterapia no cenário odontológico: uma terapêutica em ascensão–revisão de literatura. Anais do Seminário Científico do UNIFACIG 5;2019.Silva Garcez A, Simões Ribeiro M, Núñez SC. Laser de baixa potência: princípios básicos e aplicações clínicas na Odontologia. Rio de Janeiro: Elsevier; 2012.Miloro M. Princípios de cirurgia bucomaxilofacial de Peterson. 2. ed. São Paulo: Santos; 2008.Laureano A, Rodrigues AM. Cicatrização de feridas. Rev. da Soc. Port. Dermatologia e Venereol. 2011;69(3):355-67.Carvalho LMM, Guimarães AAS, Lopes DS. Abordagens cirúrgicas para o tratamento das recessões marginais gengivais. Anais XV Congresso Brasileiro de Estomatologia. São Pedro- SP. 2007.Shibayama R, Fugii WM. Enxerto gengival livre. UNOPAR Cient Ciênc BiolSaúde. 2000;2(1):107-11.Andrade FSS, Clark RMO, Ferreira ML. Efeitos da laserterapia de baixa potência na cicatrização de feridas cutâneas. Rev Col Bras Cir. 2014;41(2):129-33.Rocha JCT. Terapia laser, cicatrização tecidual e angiogênese. Rev Bras Promoção Saúde. 2004;17(1):44-8.

Synthesis of methyl 4-dihydrotrisporate B and methyl trisporate B, morphogenetic factors of Zygomycetes fungi

Abstract(9Z)-Methyl 4-dihydrotrisporate B and (9Z)-methyl trisporate B, pheromones of Zygomycetes fungi, have been synthesized using Stille cross-coupling from previously described cyclohexenone precursors. Conducting the coupling without protection groups allowed for a short and stereospecific synthesis route of the late trisporoids. Stability studies for both the compounds revealed (9Z)-methyl trisporate B to be very unstable against UV irradiation.

Overexpression of Candida albicans Secreted Aspartyl Proteinase 2 or 5 Is Not Sufficient for Exacerbation of Immunopathology in a Murine Model of Vaginitis

ABSTRACT The secreted aspartyl proteinases of Candida albicans have long been implicated in virulence at the mucosal surface, including contributions to colonization and immunopathogenesis during vulvovaginal candidiasis. In an effort to disentangle hypha-associated virulence factor regulation from morphological transition, the purpose of this study was to determine if overexpression of SAP2 or SAP5 in an efg1Δ/Δ cph1Δ/Δ mutant could restore the capacity to cause immunopathology during murine vaginitis to this avirulent hypofilamentous strain. Two similar yet distinct genetic approaches were used to construct expression vectors to achieve SAP overexpression, and both genetic and functional assays confirmed elevated SAP activity in transformed strains. Similar to previous findings, intravaginal challenge of C57BL/6 mice with hypha-defective strains attained high levels of mucosal colonization but failed to induce robust vaginal immunopathology (neutrophil recruitment, interleukin-1β [IL-1β] secretion, and lactate dehydrogenase release) compared to that with the hypha-competent control. Moreover, constitutive expression of SAP2 or SAP5 in two distinct sets of such strains did not elicit immunopathological markers at levels above those observed during challenge with isogenic empty vector controls. Therefore, these results suggest that the physiological contributions of SAPs to vaginal immunopathology require hypha formation, other hypha-associated factors, or genetic interaction with EFG1 and/or CPH1 to cause symptomatic infection. Additionally, the outlined expression strategy and strain sets will be useful for decoupling other downstream morphogenetic factors from hyphal growth.

An IGF2BP3-Cdk9 Pathway Governs the Human Fetal-Adult Megakaryocyte Transition

Hematopoietic transitions that accompany fetal development, for example erythroid globin chain switching, play important roles in normal physiology and disease development. In the megakaryocyte lineage, human fetal progenitors show impaired execution of the morphogenesis program of enlargement, polyploidization, and proplatelet formation. Although these defects decline with gestational stage, they remain sufficiently severe at birth to predispose newborns to thrombocytopenia. These defects also contribute to inferior platelet recovery after cord blood stem cell transplantation and to inefficient platelet production by megakaryocytes (Mk) derived from pluripotent stem cells. In this study, comparison of neonatal versus adult human progenitors identified a blockade in the specialized positive transcription elongation factor b (P-TEFb) activation mechanism known to drive adult Mk morphogenesis. A central feature of this pathway is known to involve sustained high amplitude activation of the P-TEFb kinase (Cdk9/cyclin T1). This cascade is initiated by downregulation of core components of the repressive complex of P-TEFb: the 7SK snRNP consisting of the 7SK small nuclear RNA (7SK) and its stabilizing factors MePCE and LARP7. The resulting high amplitude activation of P-TEFb drives multiple features of Mk differentiation: induction of cytoskeletal morphogenetic factors (ACTN1, FLNA, MKL1, HIC5), silencing of erythroid genes, promotion of histone H2B K120 monoubiquitiniation (H2BUb1), and phosphorylation of Spt5 at T806 (pSpt5 T806). Critical, rate-limiting steps triggering this pathway comprise MePCE proteolysis by calpain 2 and downregulation of LARP7, both resulting in destabilization of 7SK. In comparison to Mk derived from adult peripheral blood stem cells (adult Mk), Mk derived from umbilical cord blood stem cells (neonatal Mk) showed evidence of decreased P-TEFb activation with decreases in: 1) the expression of the cytoskeletal morphogenetic factors, 2) global H2BUb1, and 3) pSpt5 T806. In addition, neonatal Mk retained expression of the erythroid marker glycophorin A (GPA). Surprisingly, neonatal Mk failed to downregulate 7SK despite the downregulation of its stabilizers MePCE and LARP7, suggesting the existence of alternative 7SK stabilizing factor/s unique to neonatal Mk. Our screening identified the oncofetal RNA-binding protein IGF2BP3 to be expressed in neonatal but not adult Mk, and ectopic expression of IGF2BP3 in adult Mk conferred neonatal phenotypic features including reduction in size, increased proliferation and leaky erythroid antigen expression. Immunoprecipitation and glycerol gradient studies indicated the participation of IGF2BP3 in the 7SK snRNP complex. Mining of endogenous IGF2BP3 iCLIP data indicated that 7SK is one of the top direct targets of IGF2BP3 and further mapped binding to the 7SK fourth hairpin, a critical stability determinant. In loss of function studies, the knockdown of IGF2BP3 in neonatal Mk resulted in destabilization of 7SK and upregulation of the Mk morphogenetic cytoskeletal factors, as well as increased levels of H2BUb1, pSpt5 T806, and hyperphosphorylated RNA Pol II. Phenotypically, the knockdown of IGF2BP3 in neonatal Mk elicited adult features including increased size, enhanced polyploidization, reduced proliferation and silencing of erythroid antigen expression. Collectively, these findings suggest that the block in P-TEFb activation in neonatal Mk results from ontogentic stage-specific expression of IGF2BP3 which prevents the 7SK destabilization normally associated with adult megakaryocytic P-TEFb activation. We also identified a pharmacologic approach to inhibit IGF2BP3 expression, through inhibition of bromodomain and extra- terminal (BET) proteins, which reproducibly promoted adult features in neonatal Mk including enlargement, inhibition of erythroid antigen expression, upregulation of morphogenetic cytoskeletal factors, and increased platelet formation in vitro. Enforced expression of IGF2BP3 in neonatal Mk significantly blunted the effects of BET inhibitors indicating the specificity of their action in downregulating IGF2BP3. These results identify IGF2BP3 as a human ontogenic masterswitch that restricts megakaryocyte development through modulating a lineage-specific P-TEFb activation mechanism, revealing new strategies toward enhancing platelet production. Disclosures No relevant conflicts of interest to declare.