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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
3.
Eur Heart J ; 42(42): 4285-4289, 2021 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-34743214
5.
J Egypt Natl Canc Inst ; 33(1): 32, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34719756

RESUMO

BACKGROUND: Cancer refers to a group of some of the worldwide most diagnosed and deadliest pathophysiological conditions that conquered researchers' attention for decades and yet begs for more questions for a full comprehension of its complex cellular and molecular pathology. MAIN BODY: The disease conditions are commonly characterized by unrestricted cell proliferation and dysfunctional replicative senescence pathways. In fact, the cell cycle operates under the rigorous control of complex signaling pathways involving cyclins and cyclin-dependent kinases assumed to be specific to each phase of the cycle. At each of these checkpoints, the cell is checked essentially for its DNA integrity. Genetic defects observed in these molecules (i.e., cyclins, cyclin-dependent kinases) are common features of cancer cells. Nevertheless, each cancer is different concerning its molecular and cellular etiology. These could range from the genetic defects mechanisms and/or the environmental conditions favoring epigenetically harbored homeostasis driving tumorigenesis alongside with the intratumoral heterogeneity with respect to the model that the tumor follows. CONCLUSIONS: This review is not meant to be an exhaustive interpretation of carcinogenesis but to summarize some basic features of the molecular etiology of cancer and the intratumoral heterogeneity models that eventually bolster anticancer drug resistance for a more efficient design of drug targeting the pitfalls of the models.


Assuntos
Transição Epitelial-Mesenquimal , Neoplasias , Biologia , Proliferação de Células , Humanos , Neoplasias/genética , Transdução de Sinais
6.
Zootaxa ; 4996(1): 153-162, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34810541

RESUMO

The hitherto unknown female of Apocolotois smirnovi (Romanoff, 1885) is described based on two specimens from Tbilisi, Georgia. To date, only males of this rare Transcaucasian species were known. The results of DNA barcoding are presented, larva and pupa of A. smirnovi are figured, and the biology and distribution of the species are commented on.


Assuntos
Lepidópteros , Mariposas , Animais , Biologia , DNA , Feminino , Larva , Masculino , Mariposas/genética , Pupa
7.
Zootaxa ; 5060(4): 566-574, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34810649

RESUMO

Although diverse and widespread, there is much to improve on the knowledge of Zethus Fabricius, 1804 wasps. This includes aspects of many areas, such as data on taxonomy, behavior and biology. In the present study, we investigated Zethus plaumanni Bohart Stange, 1965, a species hitherto known only from the female type in the literature, and worked to fill gaps on the knowledge of this species by describing the male and its genitalia, the nest structure and giving notes on the biology of individuals collected in trap-nests in southern Brazil. The male is diagnosable by characters also used for female identification. The nest follows the pattern of typical pre-existing cavity users, with a remarkable multi-layered nest plug. Sex ratio follows the 1:1 rule and sampling indicates diapause in the adult phase.


Assuntos
Himenópteros , Vespas , Distribuição Animal , Animais , Biologia , Brasil , Feminino , Genitália , Masculino , Comportamento de Nidação
8.
Zootaxa ; 5067(1): 40-54, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34810762

RESUMO

Mecolenus wahlbergi Schoenherr, the sole member of the basal apionine tribe Mecolenini and one of the least known South African weevils, was re-discovered at a new locality at Umtamvuna River separating KwaZulu-Natal and Eastern Cape provinces. It was found feeding on leaves of the Broad-leaved Wild-quince Cryptocarya latifolia Sond. (Lauraceae), which is the first record on the biology of this species. The distribution of M. wahlbergi is summarized and mapped, including unpublished records based primarily on the specimens deposited at the Durban Natural Science Museum. Concordance between the distribution of the weevil and its putative host C. latifolia is discussed. The adult morphology of M. wahlbergi is re-described and illustrated.


Assuntos
Besouros , Lauraceae , Gorgulhos , Animais , Biologia , África do Sul
9.
Zootaxa ; 5052(1): 91-104, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34810886

RESUMO

The immature stages, morphology, and systematic position of Bombyx incomposita (van Eecke, 1929) are reported. The morphology of larva was investigated using scanning electron microscopy, and the phylogeny was inferred using six genes (COI, CAD, EF-1, GAPDH, RpS5, and wgl). The molecular phylogeny strongly supported that B. incomposita is sister to B. huttoni Westwood, 1847. The divergence of the COI barcode, phylogenetic reconstruction, and difference in immature stages support the current classification, in which the species incomposita belongs to the genus Bombyx. We give illustrations of male and female genitalia and briefly discuss the utility of the chaetotaxy of the first instar larvae on taxonomy of silkmoths. The SV group bears six setae in B. mandarina, but eight in B. incomposita. The L1 bears three setae in Rotunda, but just single seta in Bombyx.


Assuntos
Bombyx , Lepidópteros , Animais , Biologia , Bombyx/genética , Feminino , Larva , Masculino , Filogenia
10.
Zootaxa ; 5039(2): 263-276, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34811083

RESUMO

Epermenia (Calotripis) sinjovi Gaedike, 1993, feeding on Angelica pubescens Maxim. and A. ursina Maxim., was previously recorded in Russia (Far East, Southern Siberia and Transbaikalia), Kunashir Island and Japan. This species is for the first time reported in China by rearing from a new host plant A. polymorpha Maxim. The larva and pupa are illustrated and described for the first time. Available biological information associated with the new host plant is also reported. Reference DNA barcodes are provided for E. (C.) sinjovi, which confirms that forewing distinct colors and morphological differences found in venation and genitalia among individuals are intraspecific variations. The adult morphological variations within population are analyzed and discussed.


Assuntos
Código de Barras de DNA Taxonômico , Mariposas , Animais , Biologia , China , Mariposas/genética , Pupa
11.
Zootaxa ; 5039(2): 179-200, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34811088

RESUMO

A key to larvae of Ptychopteridae (phantom crane flies) is provided for species inhabiting Northern Europe. The key encompasses seven species, including the previously undescribed larvae of Ptychoptera longicauda (Tonnoir 1919). Larval specimens examined were primarily sampled from sites in Denmark. Larvae were associated with correctly identified adults based on DNA barcode (COI) sequence. In the development of the key, a wide suite of morphological characteristics were examined and evaluated for their utility to separate species. Current distribution maps are provided for all species occurring within Northern Europe. Based on records of larvae from Denmark and Finland, notes on larval habitats are given. We also present flight periods for all species examined during this study. Finally, the status of the enigmatic species Ptychoptera obscura (Peus 1958) is briefly discussed.


Assuntos
Dípteros , Animais , Biologia , Dípteros/genética , Europa (Continente) , Larva/genética , Nematóceros
12.
Zootaxa ; 5039(1): 144-148, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34811091

RESUMO

To date, 20 species of Kurixalus Ye, Fei, and Dubois have been described, and all of these species are distributed throughout South and Southeast Asia, from eastern India, throughout Myanmar and the mountainous regions of southern China, to Indochina, western and northern peninsular Thailand, Malaysia, Sumatra, Borneo, and the Philippines (Frost 2021). Descriptions of the tadpoles of only 6 species have been published: K. berylliniris and K. wangi Wu, Huang, Tsai, Li, Jhang, Wu (Wu et al. 2016); K. eiffingeri (Boettger) (Kuramoto Wang 1987); K. idiootocus (Kuramoto Wang) (Kuramoto Wang 1987); K. cf. verrucosus (Boulenger) (Ziegler Vences 2002), and Kurixalus yangi Yu, Hui, Rao, Yang (Humtsoe et al. 2020). A description of the tadpoles of K. baliogaster (Inger, Orlov, Darevsky) is also given in the species description (Inger et al. 1999), but described larvae are assigned tentatively to this species in the published text. Additional studies on the identification of the conspecificity of the described tadpoles with K. baliogaster have not been conducted. Based on the much larger size of the tadpole body (TL up to 40.3 mm), as well as the labial tooth row formula 6(26)/5(1) given by Inger et al. (1999), we concluded that these described tadpoles cannot be larval K. baliogaster and most likely belong to some other species of rhacophorid frogs.


Assuntos
Anuros , Biologia , Animais , Larva , Filogenia , Vietnã
14.
Clin Drug Investig ; 41(12): 1027-1036, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34780022

RESUMO

Heart failure (HF) is a common cause of cardiovascular mortality and morbidity. Despite advances in treatment, the prognosis remains poor. Sodium-glucose co-transporter 2 (SGLT-2) inhibitors decrease HF events by 27-39% in high-risk patients with type 2 diabetes mellitus (T2DM). Moreover, the DAPA-HF and EMPEROR-Reduced studies randomized patients with HF with reduced ejection fraction (HFrEF) with or without diabetes mellitus to receive guideline-directed medical therapy versus guideline-directed medical therapy plus an SGLT-2 inhibitor. Both studies showed the benefits of SGLT-2 inhibitors. In addition, SGLT-2 inhibitors have shown improvement according to the EMPEROR-Preserved study of HF with preserved ejection fraction (HFpEF). Therefore, a panel of cardiology experts from the Egyptian Atherosclerosis and Vascular Biology Association (EAVA) revised the literature for SGLT-2 inhibitors in HF, along with the recommended indications and contraindications, and this article presents their consensus on the topic. The panel concluded that SGLT-2 inhibitors have significantly benefited patients with chronic HFrEF, as indicated through the DAPA-HF and EMPEROR-Reduced trials. The panel recommended early use of dapagliflozin 10 mg or empagliflozin 10 mg in patients with symptomatic chronic HFrEF, whether diabetic or non-diabetic, to ameliorate HF hospitalization rate, mortality, symptoms, and decline in renal function.


Assuntos
Aterosclerose , Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Inibidores do Transportador 2 de Sódio-Glicose , Aterosclerose/tratamento farmacológico , Biologia , Consenso , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Egito , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Volume Sistólico
15.
CBE Life Sci Educ ; 20(4): ar60, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34605666

RESUMO

College students' performance in introductory-level biology course work is an important predictor of ongoing persistence in the major. This study reports on a researcher-educator partnership that designed and compared two cocurricular workshops. Seventeen laboratory sections of an undergraduate biology course were randomly assigned to one of two educational interventions during the regularly scheduled lab class section after students had completed and received the results for the first exam. The baseline Metacognition intervention was an hourlong workshop focused on effective learning strategies and self-awareness in the learning process; the extended Metacognition plus Time Management (Metacognition+TM) intervention included the aforementioned workshop plus a second hourlong workshop on time management and procrastination. Based on three exams and self-report surveys administered before the intervention and at the end of the semester, students who participated in the Metacognition+TM intervention experienced greater increases in their exam scores and degree commitment than those in the baseline intervention. Additionally, group status moderated the effect of the intervention, as the Metacognition+TM intervention was especially effective in increasing use of time management tools by students from minoritized groups.


Assuntos
Sucesso Acadêmico , Metacognição , Biologia/educação , Avaliação Educacional , Humanos , Aprendizagem , Estudantes
16.
CBE Life Sci Educ ; 20(4): ar63, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34618540

RESUMO

We examine the impact of Biology Mentoring and Engagement (BIOME) near-peer mentorship on 437 first-year undergraduate students over three cohort years. The BIOME course consists of ten, 50-minute meetings where groups of six first-year mentees meet with an upper-division student mentor to discuss topics including metacognition, growth mindset, and effective study strategies. We employed a mixed-methods approach to evaluate the impact of BIOME on mentee academic outcomes. Initial ethnographic analysis revealed that BIOME influenced student study methods, approaches to academic challenges, and use of campus learning communities. We then constructed a novel, program-specific instrument to measure the implementation of these habits, a construct we named "academic habit complexity." Regression analysis supported the hypothesis that enrollment in BIOME leads to students using more diverse approaches than their peers. Enrollment in BIOME, and the associated development of academic habit complexity, is related to higher course grades in General Chemistry, a biology major prerequisite. Finally, students participating in BIOME demonstrated improved short-term student retention as measured by increased enrollment in the subsequent prerequisite General Chemistry course. These results suggest that course-based near-peer mentorship may be an effective and scalable approach that can promote student academic success.


Assuntos
Desempenho Acadêmico , Tutoria , Biologia , Humanos , Mentores , Estudantes
17.
Artigo em Inglês | MEDLINE | ID: mdl-34639387

RESUMO

The paradigm of the Somatic Mutation Theory (SMT) is failing, and a new paradigm is underway but not yet established. What is being challenged is a conceptual approach that involves the entire human biology and the development of chronic diseases. The behavior of breast and other solid cancers is compatible with the concept that the primary tumor is able to control its microscopic metastases, in the same way that an organ (e.g., the liver) is able to control its physiological size. This finding suggested that cancer and its metastases may behave as an organoid. The new paradigm under construction considers the origin of tumors as a disturbance in the communication network between tissue cell populations and between cells and extracellular matrix, and supports a systemic approach to the study of both healthy and pathologic tissues. The commentary provides a rationale for the role of physical exercise in the control of tumor dormancy according to a human evolutionary perspective.


Assuntos
Neoplasias , Doenças não Transmissíveis , Biologia , Humanos , Neoplasias/epidemiologia , Doenças não Transmissíveis/epidemiologia , Pandemias
18.
Braz J Biol ; 83: e247433, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669794

RESUMO

The life cycle of stink bug, Glyphepomis dubia and the development of two egg parasitoids (Telenomus podisi and Trissolcus basalis) were studied at the Federal University of Maranhão, at 26 ± 2oC, relative humidity (RH) of 60 ± 10% and 12h photophase. Individuals used in the study were collected from seven rice fields located around the municipality of Arari, Maranhão, Brazil, and maintained in greenhouse and laboratory for the life cycle studies. From egg to adult, G. dubia took 35.2 days to complete the life cycle. The oviposition period was 37 days, with egg masses of about 12 eggs each and viability of 93.1%. Longevity was 53 and 65 days for females and males, respectively. The egg parasitoids Te. podisi and Tr. basalis parasitized and developed in G. dubia eggs; however, the biological characteristics of Tr. basalis were affected. Emergence of the parasitoids was higher for Te. podisi (83.5%) compared to the records for Tr. basalis (50.4%). Therefore, G. dubia may potentially achieve a pest status and Te. podisi is a promising biological control agent for G. dubia management in Brazil due to its higher longevity and better reproductive parameters.


Assuntos
Hemípteros , Heterópteros , Himenópteros , Oryza , Vespas , Animais , Biologia , Humanos , Oviposição , Óvulo
19.
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
20.
Redox Biol ; 47: 102164, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34656823

RESUMO

Iron-sulfur (Fe-S) clusters are essential cofactors most commonly known for their role mediating electron transfer within the mitochondrial respiratory chain. The Fe-S cluster pathways that function within the respiratory complexes are highly conserved between bacteria and the mitochondria of eukaryotic cells. Within the electron transport chain, Fe-S clusters play a critical role in transporting electrons through Complexes I, II and III to cytochrome c, before subsequent transfer to molecular oxygen. Fe-S clusters are also among the binding sites of classical mitochondrial inhibitors, such as rotenone, and play an important role in the production of mitochondrial reactive oxygen species (ROS). Mitochondrial Fe-S clusters also play a critical role in the pathogenesis of disease. High levels of ROS produced at these sites can cause cell injury or death, however, when produced at low levels can serve as signaling molecules. For example, Ndufs2, a Complex I subunit containing an Fe-S center, N2, has recently been identified as a redox-sensitive oxygen sensor, mediating homeostatic oxygen-sensing in the pulmonary vasculature and carotid body. Fe-S clusters are emerging as transcriptionally-regulated mediators in disease and play a crucial role in normal physiology, offering potential new therapeutic targets for diseases including malaria, diabetes, and cancer.


Assuntos
Proteínas Ferro-Enxofre , Ferro , Biologia , Ferro/metabolismo , Proteínas Ferro-Enxofre/genética , Mitocôndrias/metabolismo , Enxofre/metabolismo
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