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Buzz-pollination in Neotropical bees:genus-dependent frequencies and lack of optimal frequency for pollen release

Insect Science 2020年第1期27卷 133-142页

作者： conrado augusto rosi-denadai Priscila Cassia Souza Araujo Lucio Antonio de Oliveira Campos Lirio Cosme Jr. Raul Narciso Carvalho Guedes Departamento de Entomologia Universidade Federal de VigosaVigosaMinas GeraisBrazil Departamento de Biologia Geral Universidade Federal de VigosaVigosaMinas GeraisBrazil

Over 50 genera of bees release pollen from flower anthers using thoracic vibrations,a phenomenon known as buzz-pollination.The efficiency of this process is directly affected by the mechanical properties of the buzzes,namely the duration,amplitude,and frequency.Nonetheless,although the effects of the former two properties are well described,the role of buzz frequency on pollen release remains unclear.Furthermore,nearly all of the existing studies describing vibrational properties of natural buzz-pollination are limited to bumblebees(Bombus)and carpenter bees(Xvlocopa)constraining our current understanding of this behavior and its evolution.Therefore,we attempted to minimize this shortcoming by testing whether flower anthers exhibit optimal frequency for pollen release and whether bees tune their buzzes to match these(optimal)frequencies.If true,certain frequencies will trigger more pollen release and lighter bees will reach buzz frequencies closer to this optimum to compensate their smaller buzz amplitudes.Two strategies were used to test these hypotheses:(i)the use of(artificial)vibrational playbacks in a broad range of buzz frequencies and amplitudes to assess pollen release by tomato plants(Solarium Ivcopersicum L.)and(ii)the recording of natural buzzes of Neotropical bees visiting tomato plants during pollination.The playback experiment indicates that although buzz frequency does affect pollen release,no optimal frequency exists for that.In addition,the recorded results of natural buzz-pollination reveal that buzz frequencies vary with bee genera and are not correlated with body size.Therefore,neither bees nor plants are tuned to optimal pollen release frequencies.Bee frequency of buzz-pollination is a likely consequence of the insect flight machinery adapted to reach higher accelerations,while flower plant response to buzz-pollination is the likely result of its pollen granular properties.

关键词： buzz amplitude buzz frequency floral sonication pollination stingless bees vibration

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Junctional epithelium and hemidesmosomes:Tape and rivets for solving the“percutaneous device dilemma”in dental and other permanent implants

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Bioactive Materials 2022年第12期7卷 178-198页

作者： Nicholas G.Fischer conrado Aparicio MDRCBB-Minnesota Dental Research Center for Biomaterials and Biomechanics University of Minnesota16-212 Moos Tower515 Delaware St.SEMinneapolisMN55455USA Division of Basic Research Faculty of OdontologyUIC Barcelona-Universitat Internacional de CatalunyaC/.Josep Trueta s/n08195Sant Cugat del VallesBarcelonaSpain Institute for Bioengineering of Catalonia(IBEC) The Barcelona Institute of Science and Technology(BIST)C/.Baldiri Reixac 10-1208028BarcelonaSpain

The percutaneous device dilemma describes etiological factors, centered around the disrupted epithelial tissue surrounding non-remodelable devices, that contribute to rampant percutaneous device infection. Natural percutaneous organs, in particular their extracellular matrix mediating the “device”/epithelium interface, serve as exquisite examples to inspire longer lasting long-term percutaneous device design. For example, the tooth’s imperviousness to infection is mediated by the epithelium directly surrounding it, the junctional epithelium (JE). The hallmark feature of JE is formation of hemidesmosomes, cell/matrix adhesive structures that attach surrounding oral gingiva to the tooth’s enamel through a basement membrane. Here, the authors survey the multifaceted functions of the JE, emphasizing the role of the matrix, with a particular focus on hemidesmosomes and their five main components. The authors highlight the known (and unknown) effects dental implant - as a model percutaneous device - placement has on JE regeneration and synthesize this information for application to other percutaneous devices. The authors conclude with a summary of bioengineering strategies aimed at solving the percutaneous device dilemma and invigorating greater collaboration between clinicians, bioengineers, and matrix biologists.

关键词： Percutaneous device Percutaneous implant Hemidesmosome Junctional epithelium Bioinspired surfaces

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Preventing Stillbirth:A Review of Screening and Prevention Strategies

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Maternal-Fetal Medicine 2022年第3期4卷 218-228页

作者： Laure Noël conrado Milani Coutinho Basky Thilaganathan Department of Obstetrics and Gynecology Centre Hospitalier Universitaire de Liège4000 LiègeBelgium Department of Gynecology and Obstetrics Hospital das ClínicasFaculdade de Medicina de Ribeirão PretoUniversidade de São PauloRibeirão PretoSP14025-000Brazil Fetal Medicine Unit St George’s University Hospitals NHS Foundation TrustBlackshaw RoadLondonSW170QTUnited Kingdom.

Stillbirth is a devastating pregnancy complication that still affects many women,particularly from low and middle-income countries.It is often labeled as“unexplained”and therefore unpreventable,despite the knowledge that placental dysfunction has been identified as a leading cause of antepartum stillbirth.Currently,screening for pregnancies at high-risk for placental dysfunction relies on checklists of maternal risk factors and serial measurement of symphyseal-fundal height to identify small for gestational age fetuses.More recently,the first-trimester combined screening algorithm developed by the Fetal Medicine Foundation has emerged as a better tool to predict and prevent early-onset placental dysfunction and its main outcomes of preterm preeclampsia,fetal growth restriction and stillbirth by the appropriate use of Aspirin therapy,serial growth scans and induction of labour from 40 weeks for women identified at high-risk by such screening.There is currently no equivalent to predict and prevent late-onset placental dysfunction,although algorithms combining an ultrasound-based estimation of fetal weight,assessment of maternal and fetal Doppler indices,and maternal serum biomarkers show promise as emerging new screening tools to optimize pregnancy monitoring and timing of delivery to prevent stillbirth.In this review we discuss the strategies to predict and prevent stillbirths based on firsttrimester screening as well as fetal growth and wellbeing assessment in the second and third trimesters.

关键词： Biomarkers Fetal growth restriction Placental dysfunction Prevention Screening Stillbirth

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Heterostructure engineering in electrode materials for sodium-ion batteries:Recent progress and perspectives

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eScience 2023年第5期3卷 1-11页

作者： Eric Gabriel Chunrong Ma Kincaid Graff Angel conrado Dewen Hou Hui Xiong Micron School of Materials Science and Engineering Boise State UniversityBoiseID83725USA X-ray Sciences Division Argonne National LaboratoryLemontIL60439USA College of Textiles&Clothing Qingdao UniversityQingdao266071China Key Laboratory of Bio-Fibers and Eco-Textiles Qingdao UniversityQingdao266071China Center for Nanoscale Materials Argonne National LaboratoryLemontIL60439USA Center for Advanced Energy Studies Idaho FallsID83401USA

Sodium-ion batteries(SIBs)have stepped into the spotlight as a promising alternative to lithium-ion batteries for large-scale energy storage systems.However,SIB electrode materials,in general,have inferior performance than their lithium counterparts because Nat is larger and heavier than Lit.Heterostructure engineering is a promising strategy to overcome this intrinsic limitation and achieve practical SIBs.We provide a brief review of recent progress in heterostructure engineering of electrode materials and research on how the phase interface influences Nat storage and transport properties.Efficient strategies for the design and fabrication of heterostructures(in situ methods)are discussed,with a focus on the heterostructure formation mechanism.The heterostructure's influence on Nat storage and transport properties arises primarily from local distortions of the structure and chemomechanical coupling at the phase interface,which may accelerate ion/electron diffusion,create additional active sites,and bolster structural stability.Finally,we offer our perspectives on the existing challenges,knowledge gaps,and opportunities for the advancement of heterostructure engineering as a means to develop practical,highperformance sodium-ion batteries.

关键词： Heterostructure Sodium-ion batteries Electrode materials Heterogeneous materials Interface engineering Intergrowth

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Development of a 3D matrix for modeling mammalian spinal cord injury in vitro

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Neural Regeneration Research 2016年第11期11卷 1810-1815页

作者： Juan Felipe Diaz Quiroz Yuping Li conrado Aparicio Karen Echeverri Department of Genetics Cell Biology and Development University of Minnesota Minneapolis MN USA Center for Biotechnology and Interdisciplinary Studies Rensselaer Polytechnic Institute Troy NY USA Minnesota Dental Research Center for Biomaterials and Biomechanics Department of Restorative Sciences School of Dentistry University of Minnesota Minneapolis MN USA

Spinal cord injury affects millions of people around the world, however, limited therapies are available to improve the quality of life of these patients. Spinal cord injury is usually modeled in rats and mice using contusion or complete transection models and this has led to a deeper understanding of the molecular and cellular complexities of the injury. However, it has not to date led to development of successful novel therapies, this is in part due to the complexity of the injury and the difficulty of deciphering the exact roles and interactions of different cells within this complex environment. Here we developed a collagen matrix that can be molded into the 3D tubular shape with a lumen and can hence support cell interactions in a similar architecture to a spinal cord. We show that astrocytes can be successfully grown on this matrix in vitro and when injured, the cells respond as they do in vivo and undergo reactive gliosis, one of the steps that lead to formation of a glial scar, the main barrier to spinal cord regeneration. In the future, this system can be used to quickly assess the effect of drugs on glial scar protein activity or to perform live imaging of labeled cells after exposure to drugs.

关键词： nerve regeneration spinal cord injury 3D scaffold in vitro models astrocytes reactive gliosis neural regeneration

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Management of occult hepatitis B virus infection:An update for the clinician

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World Journal of Gastroenterology 2011年第12期17卷 1563-1568页

作者： JoséLuis Lledó conrado Fernández María Luisa Gutiérrez Sara Ocaa Gastroenterology Unit Hospital Universitario Fundación AlcorcónAv Budapest-128922 AlcorcónMadridSpain Laboratory Unit Hospital Universitario Fundación AlcorcónAv Budapest-128922 AlcorcónMadridSpain

Occult hepatitis B virus(HBV) infection(OBI) is defined by the presence of HBV DNA in the liver tissue of individuals who test negative for hepatitis B surface antigen(HBsAg).Patients who have recovered from acute hepatitis B can carry HBV genomes for a long time and show histological patterns of mild necro-inflammation,even fibrosis,years after the resolution of acute hepatitis,without showing any clinical or biochemical evidence of liver disease.At least in conditions of immunocompetence,OBI is inoffensive itself,but when other relevant causes of liver damage are present it might make the course of the liver disease worse.The risk of HBV transmission through transfusion is related to blood donations negative for HBsAg that have been collected during the pre-seroconversion period or during chronic OBI.Use of HBV nucleic acid amplification testing and multivalent anti-HBs antibodies in the HBsAg assays is recommended for detection of true and false OBI,respectively.It is not known if prior hepatitis B immunization with an optimal anti-HBs response in cases of HBV transmission through organ transplantation can effectively modulate or abort the infection.Use of anti-viral agents as prophylaxis in patients with serological evidence of past HBV infection prevents reactivation of OBI after transplantation in most cases.Reactivation of OBI has been observed in other conditions that cause immunosuppression,in which antiviral therapy could be delayed until the HBV DNA or HBsAg becomes detectable.OBI might contribute to the progression of liver fibrosis and hepatocellular carcinoma development in patients with chronic liver disease.

关键词：秘密肝炎 B 管理输血机关移植病毒复活长期的肝疾病 Hepatocellular 癌

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Influence of occult hepatitis B virus infection in chronic hepatitis C outcomes

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世界胃肠病学杂志：英文版 2011年第12期17卷 1558-1562页

作者： conrado M Fernandez-Rodriguez Maria Luisa Gutierrez JoséLuis Lledó Maria Luisa Casas Service of Gastroenterology Hospital Universitario Fundación AlcorcónUniversity King Juan CarlosAv Budapest-128922 AlcorcónMadridSpain Service of Biochemestry Hospital Universitario Fundación AlcorcónUniversity King Juan CarlosAv Budapest-128922 AlcorcónMadridSpain

Persistence of hepatitis B virus-DNA in the sera,peripheral blood mononuclear cells or in the liver of hepatitis B surface antigen(HBsAg) -negative patients with or without serological markers of previous exposure(antibodies to HBsAg and/or to HB-core antigen) defines the entity called occult hepatitis B infection(OBI).Co-infection with hepatitis B and hepatitis C viruses is frequent in highly endemic areas.While this co-infection increases the risk of liver disease progression,development of cirrhosis and hepatocellular carcinoma and also increases the rate of therapeutic failure to interferon-based treatments than either virus alone,a potentially negative effect of OBI on clinical outcomes and of therapeutic response to current antiviral regimes of patients with chronic hepatitis C remains inconclusive.

关键词：秘密肝炎 B 感染长期的丙肝结果

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Clinical significance of occult hepatitis B virus infection

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World Journal of Gastroenterology 2011年第12期17卷 1549-1552页

作者： Miriam Romero Antonio Madejón conrado Fernández-Rodríguez Javier García-Samaniego Hepatology Unit Hospital Carlos ⅢCIBERehd28029 MadridSpain Service of Gastroenterology Hospital Universitario Fundación AlcorcónAv Budapest-128922 AlcorcónMadridSpain

Occult hepatitis B virus(HBV) infection(OBI) is defined as the presence of HBV DNA in the liver(with or without detectable HBV DNA in serum) for individuals testing HBV surface antigen negative.Until recently,the clinical effect of OBI was unclear on the progression of liver disease;on the development of hepatocellular carcinoma;and on the risk for reactivation or transmission of HBV infection.Several studies suggest a high prevalence of OBI among patients with cryptogenic chronic liver disease,but its role in the progression to cirrhosis remains unclear.Although OBI has been well documented in human immunodeficiency virus(HIV) -positive patients,especially among those coinfected with hepatitis C virus,further studies are needed to determine its current clinical impact in HIV setting.

关键词：秘密肝炎 B 病毒感染肝疾病起因不明的 cirrosis 肝炎 B 病毒 coinfection 人的免疫不全病毒

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Prevalence of occult hepatitis B virus infection

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World Journal of Gastroenterology 2011年第12期17卷 1538-1542页

作者： Maria Luisa Gutiérrez-García conrado M Fernandez-Rodriguez Jose Luis Lledo-Navarro Ingrid Buhigas-Garcia Service of Gastroenterology Hospital Universitario Fundación AlcorcónAv Budapest-128922 AlcorcónMadridSpain

Occult hepatitis B virus(HBV) infection(OBI) is characterized by the persistence of HBV DNA in the liver tissue in individuals negative for the HBV surface antigen.The prevalence of OBI is quite variable depending on the level of endemic disease in different parts of the world,the different assays utilized in the studies,and the different populations studied.Many studies have been carried out on OBI prevalence in different areas of the world and categories of individuals.The studies show that OBI prevalence seems to be higher among subjects at high risk for HBV infection and with liver disease than among individuals at low risk of infection and without liver disease.

关键词：秘密肝炎 B 病毒感染肝炎 B 病毒 DNA Anti-HBc 肝炎 B 病毒 seronegative 丙肝 Crytogenetic 肝炎分离人的免疫不全病毒献血者

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Injection of bone marrow mesenchymal stem cells by intravenous or intraperitoneal routes is a viable alternative to spinal cord injury treatment in mice

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Neural Regeneration Research 2018年第6期13卷 1046-1053页

作者： Bruna dos Santos Ramalho FernANDa Martins de Almeida conrado Mendonca Sales Silmara de Lima Ana Maria Blanco Martinez Laboratorio de Neurodegeneracao e Reparo Departamento de Patologia - Faculdade de Medicina HUCFF Universidade Federal do Rio de Janeiro Rio de laneiro Brazil

In spite of advances in surgical care and rehabilitation, the consequences of spinal cord injury （SCI） are still challenging. Several experimental therapeutic strategies have been studied in the SCI field, and recent advances have led to the development of therapies that may act on the inhibitory microenvironment. Assorted lineages of stem cells are considered a good treatment for SCI. This study investigated the effect of systemic transplantation of mesenchymal stem cells （MSCs） in a compressive SCI model. Here we present results of the intraperitoneal route, which has not been used previously for MSC administration after compressive SCI. We used adult female C57BL/6 mice that underwent laminectomy at the T9 level, followed by spinal cord compression for 1 minute with a 30-g vascular clip. The animals were divided into five groups： sham （anesthesia and laminectomy but without compression injury induction）, MSC i.p. （intraperitoneal injection of 8×10^5 MSCs in 500 μL of DMEM at 7 days after SCI）, MSC i.v. （intravenous injection of 8 × 10^5 MSCs in 500μL of DMEM at 7 days after SCI）, DMEM i.p. （intraperitoneal injection of 500μL of DMEM at 7 days after SCI）, DMEM i.v. （intravenous injection of 500 μL of DMEM at 7 days after SCI）. The effects of MSCs transplantation in white matter sparing were analyzed by luxol fast blue staining. The number of preserved fibers was counted in semithin sections stained with toluidine blue and the presence of trophic factors was analyzed by immunohistochemistry. In addition, we analyzed the locomotor performance with Basso Mouse Scale and Global Mobility Test. Our results showed white matter preservation and a larger number of preserved fibers in the MSC groups than in the DMEM groups. Furthermore, the MSC groups had higher levels of trophic factors （brain-derived neurotrophic factor, nerve growth factor, neurotrophin-3 and neurotrophin-4） in the spinal cord and improved locomotor performance. Our results indicate that injection of MSCs by either intraperitoneal or intravenous route

关键词： spinal cord injury mesenchymal stem cells intravenous route intraperitoneal route functional recovery systemic transplantation neural regeneration

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