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1.
J Med Genet ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051257

RESUMO

BACKGROUND: Asthenoteratospermia, one of the most common causes for male infertility, often presents with defective sperm heads and/or flagella. Multiple morphological abnormalities of the sperm flagella (MMAF) is one of the common clinical manifestations of asthenoteratospermia. Variants in several genes including DNAH1, CEP135, CATSPER2 and SUN5 are involved in the genetic pathogenesis of asthenoteratospermia. However, more than half of the asthenoteratospermia cases cannot be explained by the known pathogenic genes. METHODS AND RESULTS: Two asthenoteratospermia-affected men with severe MMAF (absent flagella in >90% spermatozoa) from consanguineous families were subjected to whole-exome sequencing. The first proband had a homozygous missense mutation c.188G>A (p.Arg63Gln) of DZIP1 and the second proband had a homozygous stop-gain mutation c.690T>G (p.Tyr230*). Both of the mutations were neither detected in the human population genome data (1000 Genomes Project, Exome Aggregation Consortium) nor in our own data of a cohort of 875 Han Chinese control populations. DZIP1 encodes a DAZ (a protein deleted in azoospermia) interacting protein, which was associated with centrosomes in mammalian cells. Immunofluorescence staining of the centriolar protein Centrin1 indicated that the spermatozoa of the proband presented with abnormal centrosomes, including no concentrated centriolar dot or more than two centriolar dots. HEK293T cells transfected with two DZIP1-mutated constructs showed reduced DZIP1 level or truncated DZIP1. The Dzip1-knockout mice, generated by the CRSIPR-Cas9, revealed consistent phenotypes of severe MMAF. CONCLUSION: Our study strongly suggests that homozygous DZIP1 mutations can induce asthenoteratospermia with severe MMAF. The deficiency of DZIP1 induces sperm centrioles dysfunction and causes the absence of flagella.

2.
J Neuroinflammation ; 17(1): 16, 2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31926558

RESUMO

OBJECTIVE: The potential roles and mechanisms of pericytes in maintaining blood-brain barrier (BBB) integrity, which would be helpful for the development of therapeutic strategies for subarachnoid hemorrhage (SAH), remain unclear. We sought to provide evidence on the potential role of pericytes in BBB disruption and possible involvement and mechanism of CypA signaling in both cultured pericytes and SAH models. METHODS: Three hundred fifty-three adult male C57B6J mice weighing 22 to 30 g, 29 CypA-/- mice, 30 CypA+/+ (flox/flox) mice, and 30 male neonatal C57B6J mice were used to investigate the time course of CypA expression in pericytes after SAH, the intrinsic function and mechanism of CypA in pericytes, and whether the known receptor CD147 mediates these effects. RESULTS: Our data demonstrated both intracellular CypA and CypA secretion increased after SAH and could activate CD147 receptor and downstream NF-κB pathway to induce MMP9 expression and proteolytic functions for degradation of endothelium tight junction proteins and basal membranes. CypA served as autocrine or paracrine ligand for its receptor, CD147. Although CypA could be endocytosed by pericytes, specific endocytosis inhibitor chlorpromazine did not have any effect on MMP9 activation. However, specific knockdown of CD147 could reverse the harmful effects of CypA expression in pericytes on the BBB integrity after SAH. CONCLUSIONS: This study demonstrated for the first time that CypA mediated the harmful effects of pericytes on BBB disruption after SAH, which potentially mediated by CD147/NF-κB/MMP9 signal, and junction protein degradation in the brain. By targeting CypA and pericytes, this study may provide new insights on the management of SAH patients.

3.
J Cell Biol ; 219(2)2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31895406

RESUMO

Escape of large macromolecular complexes from the endoplasmic reticulum (ER), such as a viral particle or cellular aggregate, likely induces mechanical stress initiated on the luminal side of the ER membrane, which may threaten its integrity. How the ER responds to this threat remains unknown. Here we demonstrate that the cytosolic leaflet ER morphogenic protein reticulon (RTN) protects ER membrane integrity when polyomavirus SV40 escapes the ER to reach the cytosol en route to infection. SV40 coopts an intrinsic RTN function, as we also found that RTN prevents membrane damage during ER escape of a misfolded proinsulin aggregate destined for lysosomal degradation via ER-phagy. Our studies reveal that although ER membrane integrity may be threatened during ER escape of large macromolecular protein complexes, the action of RTN counters this, presumably by deploying its curvature-inducing activity to provide membrane flexibility and stability to limit mechanical stress imposed on the ER membrane.

4.
Oxid Med Cell Longev ; 2020: 8285065, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31998445

RESUMO

White matter injury (WMI) is an important cause of high disability after intracerebral haemorrhage (ICH). It is widely accepted that reactive oxygen species (ROS) contributes to WMI, but there is still no evidence-based treatment. Here, mitoquinone (MitoQ), a newly developed selective mitochondrial ROS scavenger, was used to test its neuroprotective potential. The data showed that MitoQ attenuated motor function deficits and motor-evoked potential (MEP) latency prolongation. Further research found that MitoQ blunted the loss of oligodendrocytes and oligodendrocyte precursor cells, therefore reduced demyelination and axon swelling after ICH. In the in vitro experiments, MitoQ, but not the nonselective antioxidant, almost completely attenuated the iron-induced membrane potential decrease and cell death. Mechanistically, MitoQ blocked the ATP deletion and mitochondrial ROS overproduction. The present study demonstrates that the selective mitochondrial ROS scavenger MitoQ may improve the efficacy of antioxidant treatment of ICH by white matter injury alleviation.

5.
J Med Genet ; 57(2): 89-95, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31501240

RESUMO

BACKGROUND: Male infertility is a prevalent issue worldwide, mostly due to the impaired sperm motility. Multiple morphological abnormalities of the sperm flagella (MMAF) present aberrant spermatozoa with absent, short, coiled, bent and irregular-calibre flagella resulting in severely decreased motility. Previous studies reported several MMAF-associated genes accounting for approximately half of MMAF cases. METHODS AND RESULT: We conducted genetic analysis using whole-exome sequencing in 88 Han Chinese MMAF probands. CFAP65 homozygous mutations were identified in four unrelated consanguineous families, and CFAP65 compound heterozygous mutations were found in two unrelated cases with MMAF. All these CFAP65 mutations were null, including four frameshift mutations (c.1775delC [p.Pro592Leufs*8], c.3072_3079dup [p.Arg1027Profs*41], c.1946delC [p.Pro649Argfs*5] and c.1580delT [p.Leu527Argfs*31]) and three stop-gain mutations (c.4855C>T [p.Arg1619*], c.5270T>A [p.Leu1757*] and c.5341G>T [p.Glu1781*]). Additionally, two homozygous CFAP65 variants likely affecting splicing were identified in two MMAF-affected men of Tunisian and Iranian ancestries, respectively. These biallelic variants of CFAP65 were verified by Sanger sequencing and were absent or very rare in large data sets aggregating sequence information from various human populations. CFAP65, encoding the cilia and flagella associated protein 65, is highly and preferentially expressed in the testis. Here we also generated a frameshift mutation in mouse orthologue Cfap65 using CRISPR-Cas9 technology. Remarkably, the phenotypes of Cfap65-mutated male mice were consistent with human MMAF. CONCLUSIONS: Our experimental observations performed on both human subjects and on Cfap65-mutated mice demonstrate that the presence of biallelic mutations in CFAP65 causes the MMAF phenotype and impairs sperm motility.

6.
J Hazard Mater ; 383: 121142, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31639610

RESUMO

Leather wastewater is one of the most polluting industrial emissions. The efficiency of wastewater remediation is limited by its complex composition. Herein, a novel strategy for designing modified gelatine with higher degree of quaternization (MG-2) is presented. The higher degree of quaternization allows sufficient adsorption of dyes in the tanning process. It is an in situ, environmentally friendly, and innovative strategy to limit dye emissions and can circumvent the subsequent waste management. Dyes such as Direct Purple N and Acid Black 24 could be adsorbed completely within 5 min by the MG-2 film formed from MG-2 solution. In addition, a remarkable efficiency in removing Acid Red 73, Golden Orange G, and Acid Orange II (>96.1% removal rates) was achieved within 30 min. The adsorption equilibrium data suggested that the adsorption capacity was positively correlated to the concentration of MG-2. When Acid Orange II and MG-2 were used in the industrial re-tanning process, the residual dye concentration in wastewater was only 23.1 mg L-1, indicating that MG-2 is a promising re-tanning agent for adsorbing dyes in the leather tanning process.

7.
Bioresour Technol ; 299: 122560, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31882199

RESUMO

Over the past forty years, anammox-based processes have been extensively researched and applied to some extent. However, some of the long-standing problems present serious impediments to wide application of these processes, and knowledge gap between lab-scale research and full-scale operations is still considerable. In recent years, anammox-based research has developed rapidly and some emerging concepts have been proposed. The focus of this review is on the critical problems facing actual application of anammox processes. The latest developments in anammox-based processes are summarized, and particular consideration is given to the following aspects: (1) the evolution of the chemical stoichiometry of anammox reaction; (2) the status of several main anammox-based processes; (3) the critical problems and countermeasures; (4) the emerging anammox-based processes; and (5) the suggested optimal process integrating partial nitritation, anammox, hydroxyapatite crystallization and denitratation for digestion effluent treatment towards more efficient nitrogen removal and phosphorus recovery in the future.


Assuntos
Compostos de Amônio , Nitrogênio , Reatores Biológicos , Desnitrificação , Oxirredução , Fósforo
8.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(12): 1589-1592, 2019 Dec 15.
Artigo em Chinês | MEDLINE | ID: mdl-31823564

RESUMO

Objective: To summarize the application progress of indocyanine green (ICG) angiography in diagnosis and treatment of lymphedema. Methods: The literature related to dynamic imaging tracing of lymphedema at home and abroad was reviewed extensively. And the research status and progress of ICG angiography in diagnosis and treatment of lymphedema were retrospectively analyzed. Results: ICG angiography can be used as the gold standard for the diagnosis of lymphedema at present and the classification of lymphedema severity, selection of surgical incisions and methods, and intraoperative operation. It can also be used to observe lymphatic drainage and regeneration within 1.5 cm of subcutaneous and determine the prognosis. Conclusion: Compared with traditional methods, ICG angiography has more obvious advantages and value in diagnosis and treatment of lymphedema. However, it also has problems such as slow development speed and difficulty in developing deep lymphatic vessels (nodes).


Assuntos
Vasos Linfáticos , Linfedema , Linfografia , Angiografia , Humanos , Verde de Indocianina , Vasos Linfáticos/diagnóstico por imagem , Linfedema/diagnóstico por imagem , Estudos Retrospectivos
9.
Mikrochim Acta ; 187(1): 12, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31802244

RESUMO

A fluorometric method is described for the determination of fipronil, a frequently-used insecticide. It exploits the blue fluorescence of carbon quantum dots (CQDs) and the selectivity of molecularly imprinted silica (MIS). The MIS was prepared via the sol-gel method by using fipronil as the template, 3-aminopropyltriethoxysilane as functional monomer, and tetraethoxysilane as cross-linker in the presence of CQDs. The blue fluorescence of the CQD@MIS, with excitation/emission peaks at 340/422 nm, is quenched by fipronil. The assay works in the 0. 70 pM to 47 µM fipronil concentration range, and the limit of detection is 19 pM. The method was successfully applied to the quantitation of fipronil in spiked eggs, milk, and tap water. Recoveries between 83.8 and 114.0% were achieved. The corresponding relative standard deviations (RSD) are less than 6.67%. Graphical abstractSchematic representation of a high sensitivite and selectivite fluorescence nanoprobe constructed by combining the excellent fluorescence property of carbon quantum dots and the predicted selectivity of molecularly imprinted silica. It was applied to analyze fipronil in egg, milk and tap water, respectively.

10.
Sci Rep ; 9(1): 16958, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31740745

RESUMO

Motor function deficit induced by white matter injury (WMI) is one of the most severe complications of intracerebral haemorrhage (ICH). The degree of WMI is closely related to the prognosis of patients after ICH. However, the current behavioural assessment of motor function used in the ICH mouse model is mainly based on that for ischaemic stroke and lacks the behavioural methods that accurately respond to WMI. Here, a series of easy-to-implement behavioural tests were performed to detect motor deficits in mice after ICH. The results showed that the grip strength test and the modified pole test not only can better distinguish the degree of motor dysfunction between different volumes of blood ICH models than the Basso Mouse Scale and the beam walking test but can also accurately reflect the severity of WMI characterized by demyelination, axonal swelling and the latency of motor-evoked potential delay induced by ICH. In addition, after ICH, the results of grip tests and modified pole tests, rather than the Basso Mouse Scale and the beam walking test, were worse than those observed after intraventricular haemorrhage (IVH), which was used as a model of brain haemorrhage in non-white matter areas. These results indicate that the grip strength test and the modified pole test have advantages in detecting the degree of motor deficit induced by white matter injury after ICH in mice.

11.
Food Funct ; 10(11): 7416-7425, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31660551

RESUMO

The relationship between bacterial strains and serotonin regulation was studied via the in vitro screening of the strains. Using the transparent visibility of zebrafish, the strains for intestinal peristalsis were quickly screened. The methods and results were as follows: (1) 18 strains with outstanding gastrointestinal viability via their surface hydrophobicity, self-aggregation ability, acid tolerance, bile tolerance, simulated gastric digestion and intestinal fluid tolerance were determined from 54 unpublished strains. (2) 5dpf zebrafish were randomly selected and divided into 22 groups with 12 tails in each group. The intestinal peristalsis frequency of each group within 1 min was calculated after immersing the model zebrafish in a 108 CFU mL-1 strain solution, with 5 effective strains obtained. (3) The serotonin in zebrafish was measured by Elisa and fluorescence immunization. The regulation mechanism of serotonin by Bifidobacterium animalis F1-7 was revealed by RT-PCR and the results show that this most effective strain promotes intestinal peristalsis in zebrafish via the modulation of serotonin release and key genes for serotonin synthesis in zebrafish.

12.
Viruses ; 11(10)2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31590347

RESUMO

During entry, a virus must be transported through the endomembrane system of the host cell, penetrate a cellular membrane, and undergo capsid disassembly, to reach the cytosol and often the nucleus in order to cause infection. To do so requires the virus to coordinately exploit the action of cellular membrane transport, penetration, and disassembly machineries. How this is accomplished remains enigmatic for many viruses, especially for viruses belonging to the nonenveloped virus family. In this review, we present the current model describing infectious entry of the nonenveloped polyomavirus (PyV) SV40. Insights from SV40 entry are likely to provide strategies to combat PyV-induced diseases, and to illuminate cellular trafficking, membrane transport, and disassembly mechanisms.

13.
ACS Omega ; 4(14): 15947-15955, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31592465

RESUMO

Perfluorooctane sulfonate (PFOS) known as a persistent organic pollutant has been attracting great interests due to its potential ecotoxicity. An approach capable of sensing ultra-trace PFOS is in urgent demand. Here, we developed an approach for highly sensitive sensing PFOS using surfactant-sensitized covalent organic frameworks (COFs)-functionalized upconversion nanoparticles (UCNPs) as a fluorescent probe. COFs-functionalized UCNPs (UCNPs@COFs) were obtained by solvothermal growth of 1,3,5-triformylbenzene and 1,4-phenylenediamine on the surface of UCNPs. COF's layer on the surface of UCNPs not only provides recognition sites for PFOS but also improves the fluorescence quantum yields from 2.15 to 5.12%. Trace PFOS can quench the fluorescence emission of UCNPs@COFs at 550 nm due to the high electronegativity of PFOS. Moreover, the fluorescence quenching response can be significantly strengthened in the presence of a surfactant, which causes more sensitivity. The fluorescence quenching degrees (F 0 - F) of the system are linear with the concentration of PFOS in the range of 1.8 × 10-13 to 1.8 × 10-8 M. The present sensor can sensitively and selectively detect PFOS in tap water and food packing with the limit of detection down to 0.15 pM (signal-to-noise ratio = 3), which is comparable to that of the liquid chromatography-mass spectrometry technique. The proposed approach realized a simple, fast, sensitive, and selective sensing PFOS, showing potential applications in various fields.

14.
Front Cell Neurosci ; 13: 399, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31572127

RESUMO

MicroRNAs (miRs) downregulate or upregulate the mRNA level by binding to the 3'-untranslated region (3'UTR) of target gene. Dysregulated miR levels can be used as biomarkers of Parkinson's disease (PD) and could participate in the etiology of PD. In the present study, 45 brain-enriched miRs were evaluated in serum samples from 50 normal subjects and 50 sporadic PD patients. The level of miR-204-5p was upregulated in serum samples from PD patients. An upregulated level of miR-204-5p was also observed in the serum and substantia nigra (SN) of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. Expression of miR-204-5p increased the level of α-synuclein (α-Syn), phosphorylated (phospho)-α-Syn, tau, or phospho-tau protein and resulted in the activation of endoplasmic reticulum (ER) stress in SH-SY5Y dopaminergic cells. Expression of miR-204-5p caused autophagy impairment and activation of c-Jun N-terminal kinase (JNK)-mediated apoptotic cascade in SH-SY5Y dopaminergic cells. Our study using the bioinformatic method and dual-luciferase reporter analysis suggests that miR-204-5p positively regulates mRNA expression of dual-specificity tyrosine phosphorylation regulated kinase 1A (DYRK1A) by directly interacting with 3'UTR of DYRK1A. The mRNA and protein levels of DYRK1A were increased in SH-SY5Y dopaminergic cells expressing miR-204-5p and SN of MPTP-induced PD mouse model. Knockdown of DYRK1A expression or treatment of the DYRK1A inhibitor harmine attenuated miR-204-5p-induced increase in protein expression of phospho-α-Syn or phospho-tau, ER stress, autophagy impairment, and activation of JNK-mediated apoptotic pathway in SH-SY5Y dopaminergic cells or primary cultured dopaminergic neurons. Our results suggest that upregulated expression of miR-204-5p leads to the death of dopaminergic cells by targeting DYRK1A-mediated ER stress and apoptotic signaling cascade.

15.
Molecules ; 24(17)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480234

RESUMO

This work presents the first example of utilization of amphiphilic block copolymer PCL-PEG-PCL as a stationary phase for capillary gas chromatographic (GC) separations. The PCL-PEG-PCL capillary column fabricated by static coating provides a high column efficiency of 3951 plates/m for n-dodecane at 120 °C. McReynolds constants and Abraham system constants were also determined in order to evaluate the polarity and possible molecular interactions of the PCL-PEG-PCL stationary phase. Its selectivity and resolving capability were investigated by using a complex mixture covering analytes of diverse types and positional, structural, and cis-/trans-isomers. Impressively, it exhibits high resolution performance for aliphatic and aromatic isomers with diverse polarity, including those critical isomers such as butanol, dichlorobenzene, dimethylnaphthalene, xylenol, dichlorobenzaldehyde, and toluidine. Moreover, it was applied for the determination of isomer impurities in real samples, suggesting its potential for practical use. The superior separation performance demonstrates the potential of PCL-PEG-PCL and related block copolymers as stationary phases in GC and other separation technologies.


Assuntos
Cromatografia Gasosa/métodos , Poliésteres/química , Polietilenoglicóis/química , Tensoativos/química , Varredura Diferencial de Calorimetria , Isomerismo , Temperatura Ambiente , Termogravimetria
16.
Stem Cell Res ; 40: 101552, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31493761

RESUMO

Mutations in PLA2G6 gene cause PLA2G6-associated neurodegeneration, including recessive familial type 14 of Parkinson's disease (PARK14). Previously, we identified PARK14 patients with compound heterozygous c.991G > T/c.1077G > A (p.D331Y/p.M358IfsX) mutations. The c.1077G > A mutation led to a four base-pairs deletion and frameshift mutation (p.M358IfsX) of PLA2G6 mRNA. We established induced pluripotent stem cells (iPSCs) from peripheral blood mononuclear cells of a female patient with compound heterozygous c.991G > T/c.1077G > A (p.D331Y/ p.M358IfsX) mutations by using Sendai-virus delivery system. The iPSCs exhibited pluripotency and in vivo differentiation potential. The iPSCs can be used for studying the molecular pathogenic mechanism of PARK14.

17.
ACS Chem Neurosci ; 10(9): 4151-4159, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31436406

RESUMO

The aberrant self-assembly of human islet amyloid polypeptide (hIAPP) into toxic oligomers, protofibrils, and mature fibrils is associated with the pathogenesis of type 2 diabetes (T2D). Inhibition of hIAPP aggregation and destabilization of preformed hIAPP fibrils are considered as two major therapeutic strategies for treating T2D. Previous experimental studies reported that dopamine prevented the formation of hIAPP oligomers and fibrils. However, the underlying inhibitory mechanism at the atomic level remains elusive. Herein we investigated the conformational ensembles of hIAPP dimer with and without dopamine using replica-exchange molecular dynamics simulations. The simulations demonstrated that dopamine preferentially bound to R11, L12, F15, H18, F23, I26, L27, and Y37 residues, inhibited the formation of ß-sheets in the amyloidogenic regions spanning residues 11RLANFLVH18, 22NFGAIL27, and 30TNVGSNT36, and resulted in more disordered hIAPP dimers, thus hindering the amyloid formation of hIAPP. Protonated and deprotonated dopamine molecules displayed distinct binding capabilities but bound to similar residue sites on hIAPP. Additional microsecond molecular dynamics simulations showed that dopamine mainly bound to the ß1 and turn regions of hIAPP protofibril and destabilized the protofibril structure. This study not only revealed the molecular mechanism of dopamine toward the inhibition of hIAPP aggregation but also demonstrated the protofibril-destabilizing effects of dopamine, which may be helpful for the design of drug candidates to treat T2D.

18.
Adv Mater ; 31(39): e1901964, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31389096

RESUMO

Atomically thin oxychalcogenides have been attracting intensive attention for their fascinating fundamental properties and application prospects. Bi2 O2 Se, a representative of layered oxychalcogenides, has emerged as an air-stable high-mobility 2D semiconductor that holds great promise for next-generation electronics. The preparation and device fabrication of high-quality Bi2 O2 Se crystals down to a few atomic layers remains a great challenge at present. Here, molecular beam epitaxy (MBE) of atomically thin Bi2 O2 Se films down to monolayer on SrTiO3 (001) substrate is achieved by co-evaporating Bi and Se precursors in oxygen atmosphere. The interfacial atomic arrangements of MBE-grown Bi2 O2 Se/SrTiO3 are unambiguously revealed, showing an atomically sharp interface and atom-to-atom alignment. Importantly, the electronic band structures of one-unit-cell (1-UC) thick Bi2 O2 Se films are observed by angle-resolved photoemission spectroscopy (ARPES), showing low effective mass of ≈0.15 m0 and bandgap of ≈0.8 eV. These results may be constructive to the synthesis of other 2D oxychalcogenides and investigation of novel physical properties.

19.
Proc Natl Acad Sci U S A ; 116(30): 14823-14828, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31289234

RESUMO

Microrobotics extends the reach of human-controlled machines to submillimeter dimensions. We introduce a microrobot that relies on optoelectronic tweezers (OET) that is straightforward to manufacture, can take nearly any desirable shape or form, and can be programmed to carry out sophisticated, multiaxis operations. One particularly useful program is a serial combination of "load," "transport," and "deliver," which can be applied to manipulate a wide range of micrometer-dimension payloads. Importantly, microrobots programmed in this manner are much gentler on fragile mammalian cells than conventional OET techniques. The microrobotic system described here was demonstrated to be useful for single-cell isolation, clonal expansion, RNA sequencing, manipulation within enclosed systems, controlling cell-cell interactions, and isolating precious microtissues from heterogeneous mixtures. We propose that the optoelectronic microrobotic system, which can be implemented using a microscope and consumer-grade optical projector, will be useful for a wide range of applications in the life sciences and beyond.

20.
Proc Biol Sci ; 286(1906): 20190757, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31288703

RESUMO

Increasing carbon emissions not only enrich oceans with CO2 but also make them more acidic. This acidifying process has caused considerable concern because laboratory studies show that ocean acidification impairs calcification (or shell building) and survival of calcifiers by the end of this century. Whether this impairment in shell building also occurs in natural communities remains largely unexplored, but requires re-examination because of the recent counterintuitive finding that populations of calcifiers can be boosted by CO2 enrichment. Using natural CO2 vents, we found that ocean acidification resulted in the production of thicker, more crystalline and more mechanically resilient shells of a herbivorous gastropod, which was associated with the consumption of energy-enriched food (i.e. algae). This discovery suggests that boosted energy transfer may not only compensate for the energetic burden of ocean acidification but also enable calcifiers to build energetically costly shells that are robust to acidified conditions. We unlock a possible mechanism underlying the persistence of calcifiers in acidifying oceans.

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