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1.
J Cell Sci ; 135(5)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33975358

RESUMO

Lipid droplets (LDs) are lipid-rich organelles universally found in most cells. They serve as a key energy reservoir, actively participate in signal transduction and dynamically communicate with other organelles. LD dysfunction has been associated with a variety of diseases. The content level, composition and mobility of LDs are crucial for their physiological and pathological functions, and these different parameters of LDs are subject to regulation by genetic factors and environmental inputs. Coherent Raman scattering (CRS) microscopy utilizes optical nonlinear processes to probe the intrinsic chemical bond vibration, offering label-free, quantitative imaging of lipids in vivo with high chemical specificity and spatiotemporal resolution. In this Review, we provide an overview over the principle of CRS microscopy and its application in tracking different parameters of LDs in live cells and organisms. We also discuss the use of CRS microscopy in genetic screens to discover lipid regulatory mechanisms and in understanding disease-related lipid pathology.


Assuntos
Microscopia , Análise Espectral Raman , Biologia , Gotículas Lipídicas , Lipídeos
2.
Rozhl Chir ; 100(8): 409-416, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34649449

RESUMO

Nonunion is one of the common fracture healing complications. Its diagnosis is based on clinical and X-ray/CT findings. Nonunions can be classified, according to Weber and Cech, as vital and nonvital. Low mechanical stability is the main underlying factor in the development of vital nonunions and therefore, the treatment should be focused on increasing their stability. Absence of biological activity is the causal factor in the development of nonvital nonunions; thus the therapy must be bolstered by bone grafting and decortication. Treatment of nonunions is time consuming and costly and the frequency of their incidence is not decreasing. However, significant progress has been made in the treatment of patients with this bone healing defect over the last decades owing to improved understanding of its genesis and the development of osteosynthetic materials. The presented case of nonunion after periprosthetic fracture includes a detailed description of the therapeutic considerations and techniques used in subsequent phases of treatment, accompanied by radiologic and pictorial documentation. Six months after application of a wave plate, the nonunion was successfully healed. The wave plate is a rarely used implant in our countries; however, its specific biomechanical and biological characteristics significantly support healing of indicated diaphyseal nonunions.


Assuntos
Fraturas do Fêmur , Fraturas não Consolidadas , Biologia , Fenômenos Biomecânicos , Placas Ósseas , Transplante Ósseo , Fixação Interna de Fraturas , Consolidação da Fratura , Fraturas não Consolidadas/diagnóstico por imagem , Fraturas não Consolidadas/etiologia , Fraturas não Consolidadas/cirurgia , Humanos , Estudos Retrospectivos , Resultado do Tratamento
3.
Adv Exp Med Biol ; 1334: 81-111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34476746

RESUMO

This chapter discusses the history of the Museum of Anatomy at the University of Glasgow in the context of a planned themed display on obstetrics and pregnancy, centred around human female reproductive anatomy, to support a showcase of Plaster Casts made and used by William Hunter. This exhibition aims to enhance the audience's experience with an educational display of historical specimens as well as anatomical artwork and medical models. It is anticipated that the resultant exhibition will include a series of visualisations and diagrams for use within the collection display to support the audience's understanding of the biological processes involved in reproduction, foetal development and women's experiences of childbirth. The chapter considers historical and contemporary methods of visualising embryos, as well as the developing discourse around menstruation, the gendered body and the lack of diverse representation in gynaecological images, and reflects on some of the historical, scientific, situational and societal considerations needed to achieve an inclusive and accessible exhibition. It also reflects on the artist's role in the embryonic development of this exhibition. The artworks in this chapter and the more that are planned should guide viewers with intentionally inclusive visual content. The project requires considerable further development and discussion with the team of experts involved. It is hoped that this intervention will broaden the impact of the collections in this space and provide opportunities to improve audience engagement by creating content that reflects and includes the voices of society in its creation.


Assuntos
Museus , Parto , Biologia , Desenvolvimento Embrionário , Feminino , Desenvolvimento Fetal , Humanos , Gravidez
4.
Ceska Gynekol ; 86(4): 264-272, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34493052

RESUMO

Molecular classification of endometrial carcinoma is becoming an important part of the dia-gnostic process with direct therapeutic implications. Recent international guidelines, including the joint recommendation of the European Society of Gynaecological Oncology, the European Society for Radiotherapy and Oncology and the European Society of Pathology include the molecular classification into standard dia-gnostic algorithms. Molecular testing of endometrial carcinomas is also recommended in the latest (5th edition) of the World Health Organization classification of female genital tumors. Due to the need to implement these recommendations in practice, representatives of four professional societies of the Czech Medical Association of J. E. Purkyně (the Czech Oncological Society, the Oncogynecological Section of the Czech Gynecological and Obstetrical Society, the Society of Radiation Oncology, Biology and Physics, and the Society of Czech Pathologists) organized a meeting focused on this topic. Recommendation for molecular testing of endometrial carcinoma in routine dia-gnostic practice in the Czech Republic.


Assuntos
Neoplasias do Endométrio , Radioterapia (Especialidade) , Biologia , República Tcheca , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/genética , Feminino , Humanos , Técnicas de Diagnóstico Molecular , Patologistas , Física
5.
Cad Saude Publica ; 37(8): e00352820, 2021.
Artigo em Inglês, Português | MEDLINE | ID: mdl-34495102

RESUMO

In the last 25 years of the 20th century, psychopathology coded a diverse range of social phenomena under the heading of trauma, featuring the study of psychological trauma as an autonomous area progressively informed by cultural and neurobiological research. In this scenario, we witnessed the emergence of the biocultural paradigm, an epistemological perspective that seeks to elucidate the interactive trajectories by which culture and biology consolidate each other´s effects. This article will address the intersections between the field of psychological trauma and neurosciences, based on the analytical dimensions of expansion of the category of posttraumatic stress disorder (PTSD), the epistemological premises of neurobehavioral studies of stress and fear, and the limitations of the bidirectionality hypothesis advanced by contemporary cultural neurosciences. The elaboration of definitively integrative approaches can assist the development of comprehensive models capable of conceiving knowledges and practices at the level of human experience, avoiding reductionist interpretations that submit complex cultural and subjective experiences alternatingly to the imperatives of the brain and to semiologic codes of pathogenic reasoning.


Assuntos
Neurociências , Transtornos de Estresse Pós-Traumáticos , Biologia , Brasil , Humanos
6.
An Acad Bras Cienc ; 93(suppl 3): e20201613, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34550201

RESUMO

Astragalus argaeus is an endemic plant species that is under critical risk of extinction. Here we investigated its population census, breeding system and reproductive success to determine the main factors affecting restricted distribution of this species. According to the results from pollination experiments, A. argaeus was autogamous but benefit from the cross pollination (xenogamous) and the presence of pollinators increases fruit set. The pollen/ovule ratio of A. argaeus was calculated as 3119,which correspond to facultative xenogamy. Reproduction biology data obtained by both methods are quite compatible with each other. Pollen viability and stigma receptivity data showed that both stigma receptivity and pollen viability were high and was no temporal isolation throughout the anthesis. Seed viability of A. argaues was determined as 52%. The low reproductive success of the species could be attributed to low seed viability and germination rates, small population size and variations in season and climate.


Assuntos
Fabaceae , Biologia , Flores , Melhoramento Vegetal , Polinização , Reprodução
7.
CBE Life Sci Educ ; 20(4): ar58, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34581606

RESUMO

Knowledge construction is an essential scientific practice, and undergraduate research experiences (UREs) provide opportunities for students to engage with this scientific practice in an authentic context. While participating in UREs, students develop conceptualizations about how science gathers, evaluates, and constructs knowledge (science epistemology) that align with scientific practice. However, there have been few studies focusing on how students' science epistemologies develop during these experiences. Through the analysis of written reflections and three research papers and by leveraging methods informed by collaborative autoethnography, we construct a case study of one student, describing the development of her science epistemology and scientific agency during her time participating in a biology education URE. Through her reflections and self-analysis, the student describes her context-dependent science epistemology, and how she discovered a new role as a critic of scientific papers. These results have implications for the use of written reflections to facilitate epistemic development during UREs and the role of classroom culture in the development of scientific agency.


Assuntos
Estudantes , Universidades , Biologia , Currículo , Feminino , Humanos , Conhecimento
8.
Medicina (Kaunas) ; 57(9)2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34577860

RESUMO

In the last few decades, great advances have been made in the detection and treatment of cancer, thus increasing the survival rate [...].


Assuntos
Biologia , Neoplasias , Humanos , Neoplasias/diagnóstico , Taxa de Sobrevida
9.
Cesk Patol ; 57(3): 181-187, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34551568

RESUMO

Molecular classification of endometrial carcinoma is becoming an important part of the diagnostic process with direct therapeutic implications. Recent international guidelines, including the joint ESGO-ESTRO-ESP recommendation, include the molecular classification into standard diagnostic algorithms. Molecular testing of endometrial carcinomas is also recommended in the latest (5th) edition of the WHO classification of Female Genital Tumors. Due to the need to implement these recommendations in practice, representatives of four professional societies of Czech Medical Association of J. E. Purkyně (Czech Oncological Society, Oncogynecological Section of the Czech Gynecological and Obstetrical Society, Society of Radiation Oncology, Biology and Physics, and the Society of Czech Pathologists) organized a meeting focused on this topic. The result of this meeting is a joint recommendation for molecular testing of endometrial carcinoma in routine diagnostic practice in the Czech Republic.


Assuntos
Neoplasias do Endométrio , Radioterapia (Especialidade) , Biologia , República Tcheca , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/genética , Feminino , Humanos , Técnicas de Diagnóstico Molecular , Patologistas , Física
11.
CBE Life Sci Educ ; 20(4): ar56, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34546100

RESUMO

Recent evidence suggests a mental health crisis among graduate students, particularly with regard to anxiety. To manage anxieties, graduate students can employ coping strategies. Coping is an individual's response(s) to external stressors, often with the goal of reducing or tolerating the stress; these strategies are generally considered adaptive or maladaptive. Adaptive coping strategies advance individuals through problems, while maladaptive strategies prevent stressors from being resolved. We previously identified differences between teaching and research anxieties in a sample of biology graduate teaching assistants (GTAs). This study investigated whether coping with these anxieties differed in this population as well. We interviewed 23 biology GTAs twice over one year. Interview data were qualitatively analyzed using Skinner and colleagues' major coping families as categories. Biology GTAs most often used adaptive coping strategies, such as problem solving and information seeking, to manage both teaching and research anxieties. However, other coping strategies were preferentially employed for either teaching or research, suggesting differences in these aspects of graduate student life. Over one year, GTAs reduced the number of coping strategies they employed. Understanding how GTAs cope with teaching and research anxieties may inform the types of support faculty and professional development leaders can provide to graduate students.


Assuntos
Docentes , Estudantes , Adaptação Psicológica , Ansiedade , Biologia , Humanos
12.
CBE Life Sci Educ ; 20(4): ar53, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34546102

RESUMO

Concepts of molecular biology and genetics are difficult for many biology undergraduate students to master yet are crucial for deep understanding of how life works. By asking students to draw their ideas, we attempted to uncover the mental models about genes and gene expression held by biology students (n = 23) and experts (n = 18) using semistructured interviews. A large divide was identified between novice and expert conceptions. While experts typically drew box-and-line representations and thought about genes as regions of DNA that were used to encode products, students typically drew whole chromosomes rather than focusing on gene structure and conflated gene expression with simple phenotypic outcomes. Experts universally described gene expression as a set of molecular processes involving transcription and translation, whereas students often associated gene expression with Punnett squares and phenotypic outcomes. Follow-up survey data containing a ranking question confirmed students' alignment of their mental models with the images uncovered during interviews (n = 156 undergraduate biology students) and indicated that Advanced students demonstrate a shift toward expert-like thinking. An analysis of 14 commonly used biology textbooks did not show any relationship between Punnett squares and discussions of gene expression, so it is doubtful students' ideas originate directly from textbook reading assignments. Our findings add to the literature about mechanistic reasoning abilities of learners and provide new insights into how biology students think about genes and gene expression.


Assuntos
Biologia Molecular , Estudantes , Biologia , DNA , Expressão Gênica , Humanos , Resolução de Problemas
13.
Orphanet J Rare Dis ; 16(1): 395, 2021 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-34565437

RESUMO

BACKGROUND: Telomere biology disorders (TBD) such as dyskeratosis congenita (DKC) lead to progressive multi-organ failure as impaired telomere maintenance disturbs cellular proliferative capacity. A wide range of hepatic manifestations from asymptomatic liver enzyme elevation to overt liver fibrosis/cirrhosis can be observed in TBD patients. However, the incidence of hepatic involvement remains unknown. Non-invasive transient elastography (TE) predicts early fibrosis by measuring liver stiffness and may uncover subclinical liver damage in TBD patients. METHODS: Liver screening procedures of nine TBD patients from the Aachen TBD Registry are being presented retrospectively. Following clinical suspicion, TBD was diagnosed using flow-FISH with telomere length (TL) below the 1% percentile and confirmed by next-generation sequencing (NGS) detecting pathogenic mutations in telomere maintenance genes TERC or TERT. RESULTS: In all patients, TBD was first diagnosed in adulthood. Patients showed normal to slightly elevated liver function test parameters. Hepatic ultrasound revealed inhomogeneous parenchyma in seven (77.7%) and increased liver echogenicity in four patients (44.4%). Median liver stiffness was 10.7 kilopascal (kPa) (interquartile range 8.4, 15.7 kPa). Using 7.1 kPa as cut-off, 88.8% of patients were classified as moderate fibrosis to cirrhosis. CONCLUSION: Subclinical chronic liver involvement is frequent in patients with adult-onset TBD. TE could have a valuable role in the routine work-up of patients with telomere disorders including DKC for early detection of patients at risk for liver function impairment.


Assuntos
Disceratose Congênita , Técnicas de Imagem por Elasticidade , Adulto , Biologia , Disceratose Congênita/genética , Humanos , Fígado/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/genética , Sistema de Registros , Estudos Retrospectivos , Telômero/genética
15.
Front Cell Infect Microbiol ; 11: 696598, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34540716

RESUMO

The emerging understanding of Plasmodium vivax as an infection seated in extravascular spaces of its human host carries fundamentally important implications for its management as a complex clinical and public health problem. This progress begins to reverse decades of neglected research borne of the false dogma of P. vivax as an intrinsically benign and inconsequential parasite. This Review provides real world context for the on-going laboratory explorations of the molecular and cellular events in the life of this parasite. Chemotherapies against the latent reservoir impose extraordinarily complex and difficult problems of science and medicine, but great strides in studies of the biology of hepatic P. vivax promise solutions. Fundamental assumptions regarding the interpretation of parasitaemia in epidemiology, clinical medicine, and public health are being revisited and reassessed in light of new studies of P. vivax cellular/molecular biology and pathogenesis. By examining these long overlooked complexities of P. vivax malaria, we open multiple new avenues to vaccination, chemoprevention, countermeasures against transmission, epidemiology, diagnosis, chemotherapy, and clinical management. This Review expresses how clarity of vision of biology and pathogenesis may rationally and radically transform the multiple means by which we may combat this insidiously harmful infection.


Assuntos
Malária Vivax , Malária , Biologia , Humanos , Malária Vivax/tratamento farmacológico , Malária Vivax/epidemiologia , Malária Vivax/prevenção & controle , Plasmodium falciparum , Plasmodium vivax , Saúde Pública
17.
Cancer J ; 27(5): 364-370, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34570450

RESUMO

ABSTRACT: The intersection of biology and technology has led to many advancements for the field of neurosurgery. Molecular developments have led to the identification of specific mutations, allowing for more accurate discussions in regard to prognosis and treatment effect. Even amid the progress from basic science benchwork, malignant gliomas continue to have a bleak natural history in lieu of the resistance to chemotherapy and the diffuse nature of the disease, leaving room for further research to discover more effective treatment modalities. Novel imaging methods, including the emerging field of radiogenomics, involve the merging of molecular and radiographic data, enabling earlier, detailed molecular diagnoses and improved surveillance of this pathology. Furthermore, surgical advancements have led to safer and more extensive resections. This review aims to delineate the various advancements in the many facets that are used daily in the care of our glioma population, specifically pertaining to its biology, imaging modalities, and perioperative adjuncts used in the operating room.


Assuntos
Neoplasias Encefálicas , Glioma , Biologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/cirurgia , Glioma/genética , Glioma/cirurgia , Humanos , Procedimentos Neurocirúrgicos , Tecnologia
18.
Mol Cell ; 81(15): 3033-3037, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34358454

RESUMO

Some biological questions are tough to solve through standard molecular and cell biological methods and naturally lend themselves to investigation by physical approaches. Below, a group of formally trained physicists discuss, among other things, how they apply physics to address biological questions and how physical approaches complement conventional biological approaches.


Assuntos
Biofísica/métodos , Modelos Biológicos , Física/métodos , Imagem Individual de Molécula , Biologia/educação , Biofísica/tendências , Cromossomos/química , Cromossomos/ultraestrutura , Simulação por Computador , Humanos , Proteínas Motores Moleculares/química , Origem da Vida , Física/educação , Imagem Individual de Molécula/métodos
19.
Front Cell Infect Microbiol ; 11: 708834, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34395314

RESUMO

The calcium ion (Ca2+) is a ubiquitous second messenger involved in key biological processes in prokaryotes and eukaryotes. In Plasmodium species, Ca2+ signaling plays a central role in the parasite life cycle. It has been associated with parasite development, fertilization, locomotion, and host cell infection. Despite the lack of a canonical inositol-1,4,5-triphosphate receptor gene in the Plasmodium genome, pharmacological evidence indicates that inositol-1,4,5-triphosphate triggers Ca2+ mobilization from the endoplasmic reticulum. Other structures such as acidocalcisomes, food vacuole and mitochondria are proposed to act as supplementary intracellular Ca2+ reservoirs. Several Ca2+-binding proteins (CaBPs) trigger downstream signaling. Other proteins with no EF-hand motifs, but apparently involved with CaBPs, are depicted as playing an important role in the erythrocyte invasion and egress. It is also proposed that a cross-talk among kinases, which are not members of the family of Ca2+-dependent protein kinases, such as protein kinases G, A and B, play additional roles mediated indirectly by Ca2+ regulation. This statement may be extended for proteins directly related to invasion or egress, such as SUB1, ERC, IMC1I, IMC1g, GAP45 and EBA175. In this review, we update our understanding of aspects of Ca2+-mediated signaling correlated to the developmental stages of the malaria parasite life cycle.


Assuntos
Malária , Parasitos , Animais , Biologia , Cálcio/metabolismo , Sinalização do Cálcio , Eritrócitos , Parasitos/metabolismo , Plasmodium falciparum/genética
20.
Curr Protoc ; 1(8): e224, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34436832

RESUMO

Super-resolution (diffraction unlimited) microscopy was developed 15 years ago; the developers were awarded the Nobel Prize in Chemistry in recognition of their work in 2014. Super-resolution microscopy is increasingly being applied to diverse scientific fields, from single molecules to cell organelles, viruses, bacteria, plants, and animals, especially the mammalian model organism Mus musculus. In this review, we explain how super-resolution microscopy, along with fluorescence microscopy from which it grew, has aided the renaissance of the light microscope. We cover experiment planning and specimen preparation and explain structured illumination microscopy, super-resolution radial fluctuations, stimulated emission depletion microscopy, single-molecule localization microscopy, and super-resolution imaging by pixel reassignment. The final section of this review discusses the strengths and weaknesses of each super-resolution technique and how to choose the best approach for your research. © 2021 The Authors. Current Protocols published by Wiley Periodicals LLC.


Assuntos
Biologia , Imagem Individual de Molécula , Animais , Camundongos , Microscopia de Fluorescência
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