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1.
Opt Express ; 31(5): 7492-7504, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36859878

RESUMO

We have developed a method to combine morphological and chemical information for the accurate identification of different particle types using optical measurement techniques that require no sample preparation. A combined holographic imaging and Raman spectroscopy setup is used to gather data from six different types of marine particles suspended in a large volume of seawater. Unsupervised feature learning is performed on the images and the spectral data using convolutional and single-layer autoencoders. The learned features are combined, where we demonstrate that non-linear dimensional reduction of the combined multimodal features can achieve a high clustering macro F1 score of 0.88, compared to a maximum of 0.61 when only image or spectral features are used. The method can be applied to long-term monitoring of particles in the ocean without the need for sample collection. In addition, it can be applied to data from different types of sensor measurements without significant modifications.

2.
Diabetes Obes Metab ; 22(7): 1167-1175, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32115879

RESUMO

AIM: To compare nasal glucagon (NG) with intramuscular glucagon (IMG) for the treatment of insulin-induced hypoglycaemia in Japanese patients with type 1 (T1DM) or type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: This phase 3, randomized, open-label, two-treatment, two-period crossover non-inferiority study enrolled Japanese adults with T1DM or T2DM on insulin therapy, with glycated haemoglobin levels ≤86 mmol/mol (≤10%). After ≥8 hours of fasting, hypoglycaemia was induced with human regular insulin (intravenous infusion). Patients received NG 3 mg or IMG 1 mg approximately 5 minutes after insulin termination. The primary endpoint was the proportion of patients achieving treatment success [plasma glucose (PG) increase to ≥3.9 mmol/L (≥70 mg/dL) or ≥1.1 mmol/L (≥20 mg/dL) increase from the PG nadir within 30 minutes of receiving glucagon]. Non-inferiority was declared if the upper limit of the two-sided 95% confidence interval (CI) of the mean difference in the percentage of patients achieving treatment success (IMG minus NG) was <10%. RESULTS: Seventy-five patients with T1DM (n = 34) or T2DM (n = 41) were enrolled; 72 patients (50 men, 22 women) received ≥1 study drug dose (T1DM, n = 33; T2DM, n = 39). Sixty-eight patients completed the study and were evaluable. All NG- and IMG-treated patients achieved treatment success (treatment arm difference: 0%; upper limit of two-sided 95% CI 1.47%); NG met prespecified conditions defining non-inferiority versus IMG. Glucagon was rapidly absorbed after both nasal and intramuscular administration; PG profiles were similar between administration routes during the first 60 minutes post dose. Study drug-related treatment-emergent adverse events affecting >2 patients were rhinalgia, increased blood pressure, nausea, ear pain and vomiting in the NG group, and nausea and vomiting in the IMG group. CONCLUSION: Nasal glucagon was non-inferior to IMG for successful treatment of insulin-induced hypoglycaemia in Japanese patients with T1DM/T2DM, supporting use of NG as a rescue treatment for severe hypoglycaemia.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Hipoglicemia , Adulto , Glicemia , Estudos Cross-Over , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Glucagon , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Insulina , Japão , Masculino
3.
Biol Lett ; 15(10): 20190504, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31640530

RESUMO

Pectinodontid limpets are important members of deep-sea hot vents and cold seeps as can be seen by their conspicuous presence in both extant and extinct systems. They have traditionally been classified into different genera and species based on shell and radula characteristics; the reliability of these characters has been questioned but not tested thoroughly. Here, for the first time in taxa endemic to deep-sea chemosynthetic ecosystems, we combine substrate translocation with molecular data to assess the plasticity and variability of key phenotypic characters. Molecular data revealed that several 'species' of extant vent/seep pectinodontids actually represent intergrading morphotypes of a single, highly plastic, evolutionary lineage, with each morphological trait being possibly influenced differently by environmental and genetic factors. Our results challenge previous interpretations of paleoecology at fossil chemosynthetic ecosystems and highlight the importance of modern analogues in understanding fossil systems.


Assuntos
Gastrópodes , Fontes Hidrotermais , Animais , Variação Biológica da População , Ecossistema , Reprodutibilidade dos Testes
4.
Fish Shellfish Immunol ; 93: 815-822, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31419535

RESUMO

In symbiotic systems in which symbionts are transmitted horizontally, hosts must accept symbionts from the environment while defending themselves against invading pathogenic microorganisms. How they distinguish pathogens from symbionts and how the latter evade host immune defences are not clearly understood. Recognition of foreign materials is one of the most critical steps in stimulating immune responses, and pattern recognition receptors (PRRs) play vital roles in this process. In this study, we focused on a group of highly conserved PRRs, peptidoglycan recognition proteins (PGRPs), in the deep-sea mussel, Bathymodiolus septemdierum, which harbours chemosynthetic bacteria in their gill epithelial cells. We isolated B. septemdierum PGRP genes BsPGRP-S and BsPGRP-L, which encode a short- and a long-type PGRP, respectively. The short-type PGRP has a signal peptide and was expressed in the asymbiotic goblet mucous cells in the gill epithelium, whereas the long-type PGRP was predicted to include a transmembrane domain and was expressed in gill bacteriocytes. Based on these findings, we hypothesize that the secreted and transmembrane PGRPs are engaged in host defence against pathogenic bacteria and/or in the regulation of symbiosis via different cellular localizations and mechanisms.


Assuntos
Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Imunidade Inata/genética , Mytilidae/genética , Mytilidae/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Transporte/química , Perfilação da Expressão Gênica , Brânquias/imunologia , Filogenia , Alinhamento de Sequência
5.
J Am Chem Soc ; 140(27): 8544-8550, 2018 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-29906397

RESUMO

Single-walled carbon nanotubes (SWNTs) have unique near-infrared absorption and photoemission properties that are attractive for in vivo biological applications such as photothermal cancer treatment and bioimaging. Therefore, a smart functionalization strategy for SWNTs to create biocompatible surfaces and introduce various ligands to target active cancer cells without losing the unique optical properties of the SWNTs is strongly desired. This paper reports the design and synthesis of a SWNT/gel hybrid containing maleimide groups, which react with various thiol compounds through Michael addition reactions. In this hybrid, the method called carbon nanotube micelle polymerization was used to noncovalently modify the surface of SWNTs with a cross-linked polymer gel layer. This method can form an extremely stable gel layer on SWNTs; such stability is essential for in vivo biological applications. The monomer used to form the gel layer contained a maleimide group, which was protected with furan in endo-form. The resulting hybrid was treated in water to induce deprotection via a retro-Diels-Alder reaction and then functionalized with thiol compounds through Michael addition. The functionalization of the hybrid was explored using a thiol-containing fluorescent dye as a model thiol, and the formation of the SWNT-dye conjugate was confirmed by energy transfer from the dye to SWNTs. Our strategy offers a promising SWNT-based platform for biological functionalization for cancer targeting, imaging, and treatment.

6.
J Anesth ; 29(3): 373-378, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25398399

RESUMO

PURPOSE: Both paravertebral block (PVB) and thoracic epidural block (TEB) are recommended for postoperative pain relief after lung surgery. The addition of fentanyl to the anesthetic solution became popular for TEB because of the stronger effects; however, there have been few comparable trials about the addition of fentanyl to PVB. The purpose of this study was thus to compare postoperative analgesia, side effects, and complications between ultrasound-guided PVB (USG-PVB) and TEB with the addition of fentanyl to ropivacaine after lung surgery. METHODS: We examined 90 consecutive patients (age 18-75 years) scheduled for video-assisted thoracic surgery (VATS). In both groups, all blocks (four blocks in USG-PVB and one block in TEB) and one catheter insertion were performed preoperatively. Continuous postoperative infusion (0.1% ropivacaine plus fentanyl at 0.4 mg/day) was undertaken for 36 h in both groups. The recorded data included the verbal rating scale (VRS) for pain, blood pressure, side effects, complications for 2 days, and overall satisfaction score. RESULTS: There was no difference in the frequency of taking supplemental analgesics (twice or more frequently), or in VRS. Hypotension occurred significantly more frequently in TEB (n = 7/33) than in PVB (n = 1/36) (P = 0.02); on the other hand, the incidences of PONV and pruritus, as well as overall satisfaction score, were similar. There were no complications in both groups; however, the catheters migrated intrathoracically in four patients in PVB. CONCLUSION: USG-PVB achieved similar pain relief and lowered the incidence of hypotension compared with TEB. We conclude that both blocks with the same concentration of ropivacaine and fentanyl can provide adequate postoperative analgesia for VATS.


Assuntos
Anestesia Epidural/métodos , Bloqueio Nervoso/métodos , Dor Pós-Operatória/tratamento farmacológico , Cirurgia Torácica Vídeoassistida/métodos , Idoso , Amidas/administração & dosagem , Analgésicos/uso terapêutico , Anestesia Epidural/efeitos adversos , Anestesia Local/efeitos adversos , Anestesia Local/métodos , Feminino , Fentanila/administração & dosagem , Humanos , Hipotensão/epidemiologia , Hipotensão/etiologia , Masculino , Pessoa de Meia-Idade , Bloqueio Nervoso/efeitos adversos , Procedimentos Cirúrgicos Pulmonares/métodos , Ropivacaina , Cirurgia Torácica Vídeoassistida/efeitos adversos
7.
ACS Appl Mater Interfaces ; 16(22): 29112-29120, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38761179

RESUMO

Although thin-film composite membranes have achieved great success in CO2 separation, further improvements in the CO2 permeance are required to reduce the size and cost of the CO2 separation process. Herein, we report the fabrication of composite membranes with high CO2 permeability using a laser-patterned porous membrane as the support membrane. High-aspect-ratio micropatterns with well-defined micropores on their surface were carved on microporous polymer supports by a direct laser writing process using a short-pulsed laser. By using a Galvano scanner and optimizing the laser conditions and target materials, in-plane micropatterns, such as microhole arrays, microline grating, microlattices, and out-of-plane hierarchical micropatterns, were created on porous membranes. An aqueous suspension of hydrogel microparticles doped with an amine-based mobile carrier was sprayed onto the patterned surface to form a defect-free thin separation layer. The surface area of the separation layer on the patterned support is up to 80% larger than that of flat pristine membranes, resulting in a 52% higher CO2 permeance (1106 GPU) with a CO2/N2 selectivity of 172. The laser-patterned porous membranes allow the development of inexpensive and high-performance functional membranes not only for CO2 separation but also for other applications, such as water treatment, cell culture, micro-TAS, and membrane reactors.

8.
J Endocr Soc ; 8(4): bvae034, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38444629

RESUMO

Background: Rebound hyperglycemia may occur following glucagon treatment for severe hypoglycemia. We assessed rebound hyperglycemia occurrence after nasal glucagon (NG) or injectable glucagon (IG) administration in patients with type 1 diabetes (T1D) and type 2 diabetes (T2D). Methods: This was a pooled analysis of 3 multicenter, randomized, open-label studies (NCT03339453, NCT03421379, NCT01994746) in patients ≥18 years with T1D or T2D with induced hypoglycemia. Proportions of patients achieving treatment success [blood glucose (BG) increase to ≥70 mg/dL or increase of ≥20 mg/dL from nadir within 15 and 30 minutes]; BG ≥70 mg/dL within 15 minutes; in-range BG (70-180 mg/dL) 1 to 2 and 1 to 4 hours postdose; and BG >180 mg/dL 1 to 2 and 1 to 4 hours postdose were compared. Incremental area under curve (iAUC) of BG >180 mg/dL and area under curve (AUC) of observed BG values postdose were analyzed. Safety was assessed in all studies. Results: Higher proportions of patients had in-range BG with NG vs IG (1-2 hours: P = .0047; 1-4 hours: P = .0034). Lower proportions of patients had at least 1 BG value >180 mg/dL with NG vs IG (1-2 hours: P = .0034; 1-4 hours: P = .0068). iAUC and AUC were lower with NG vs IG (P = .025 and P < .0001). As expected, similar proportions of patients receiving NG or IG achieved treatment success at 15 and 30 minutes (97-100%). Most patients had BG ≥70 mg/dL within 15 minutes (93-96%). The safety profile was consistent with previous studies. Conclusion: This study demonstrated lower rebound hyperglycemia risk after NG treatment compared with IG. Clinical Trial Registration: NCT03421379, NCT03339453, NCT01994746.

9.
Circulation ; 125(11): 1402-13, 2012 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-22328542

RESUMO

BACKGROUND: The presence of chronic kidney disease is a significant independent risk factor for poor prognosis in patients with chronic heart failure. However, the mechanisms and mediators underlying this interaction are poorly understood. In this study, we tested our hypothesis that chronic cardiac volume overload leads to de novo renal dysfunction by coactivating the sympathetic nervous system and renin-angiotensin system in the kidney. We also examined the therapeutic potential of renal denervation and renin-angiotensin system inhibition to suppress renal injury in chronic heart failure. METHODS AND RESULTS: Sprague-Dawley rats underwent aortic regurgitation and were treated for 6 months with vehicle, olmesartan (an angiotensin II receptor blocker), or hydralazine. At 6 months, albuminuria and glomerular podocyte injury were significantly increased in aortic regurgitation rats. These changes were associated with increased urinary angiotensinogen excretion, kidney angiotensin II and norepinephrine (NE) levels, and enhanced angiotensinogen and angiotensin type 1a receptor gene expression and oxidative stress in renal cortical tissues. Aortic regurgitation rats with renal denervation had decreased albuminuria and glomerular podocyte injury, which were associated with reduced kidney NE, angiotensinogen, angiotensin II, and oxidative stress. Renal denervation combined with olmesartan prevented podocyte injury and albuminuria induced by aortic regurgitation. CONCLUSIONS: In this chronic cardiac volume-overload animal model, activation of the sympathetic nervous system augments kidney renin-angiotensin system and oxidative stress, which act as crucial cardiorenal mediators. Renal denervation and olmesartan prevent the onset and progression of renal injury, providing new insight into the treatment of cardiorenal syndrome.


Assuntos
Albuminúria/prevenção & controle , Insuficiência da Valva Aórtica/prevenção & controle , Rim/inervação , Podócitos/patologia , Simpatectomia , Albuminúria/complicações , Albuminúria/patologia , Animais , Insuficiência da Valva Aórtica/complicações , Insuficiência da Valva Aórtica/patologia , Linhagem Celular Transformada , Humanos , Rim/patologia , Rim/fisiologia , Masculino , Podócitos/fisiologia , Ratos , Ratos Sprague-Dawley , Simpatectomia/métodos
10.
Paediatr Drugs ; 25(3): 377-387, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36973474

RESUMO

BACKGROUND: Nasal glucagon (NG) 3 mg is approved in Japan to treat hypoglycemia in pediatric patients with diabetes, but an NG clinical study has not been performed in Japanese children because of practical and ethical concerns. OBJECTIVE: The aim of this study is to support the dose rationale for NG 3 mg in Japanese pediatric patients with diabetes using modeling and simulation. METHODS: We used a pharmacokinetic/pharmacodynamic bridging approach to extrapolate the available clinical data to Japanese pediatric patients. Population pharmacokinetic/pharmacodynamic modeling was performed using data from seven clinical studies, including five studies in non-Japanese adults, one study in Japanese adults, and one study in non-Japanese pediatric patients. Simulation was then used to estimate glucagon exposure and glucose response after NG 3-mg administration for three age categories of Japanese pediatric patients: 4 to < 8, 8 to < 12, and 12 to < 18 years. Treatment success was defined as an increase in blood glucose to ≥ 70 or ≥ 20 mg/dL from nadir within 30 min after administration of NG 3 mg. Safety was assessed in relation to the predicted maximum glucagon concentration of NG 3 mg using NG clinical trial data and published data on intravenous and intramuscular glucagon. RESULTS: The data showed a rapid and robust glucose response following NG 3 mg in Japanese and non-Japanese adults and non-Japanese pediatric patients, with some differences in glucagon exposure observed across studies. The pharmacokinetic/pharmacodynamic model described the observed clinical data well, and simulations indicated that > 99% of hypoglycemic Japanese pediatric patients in all three age groups would achieve treatment success. Predicted glucose responses to NG 3 mg in Japanese pediatric patients were comparable to those of intramuscular glucagon. Maximum concentration was not associated with the occurrence and severity of common adverse events (nausea, vomiting, and headache) in NG clinical studies. Furthermore, the predicted maximum concentration in Japanese pediatric patients, despite being higher than the observed maximum concentration in NG clinical studies, was substantially lower than the observed maximum concentration of 1 mg of intravenous glucagon, without serious safety issues. CONCLUSIONS: This analysis suggests NG 3 mg has robust efficacy without serious safety concerns in Japanese pediatric patients with diabetes.


Assuntos
Diabetes Mellitus , Hipoglicemia , Adulto , Humanos , Criança , Adolescente , Glucagon/uso terapêutico , Diabetes Mellitus/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Hipoglicemia/tratamento farmacológico , Glicemia/análise
11.
Sci Adv ; 9(25): eadd3584, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37343099

RESUMO

Foraminifera, the most ancient known calcium carbonate-producing eukaryotes, are crucial players in global biogeochemical cycles and well-used environmental indicators in biogeosciences. However, little is known about their calcification mechanisms. This impedes understanding the organismal responses to ocean acidification, which alters marine calcium carbonate production, potentially leading to biogeochemical cycle changes. We conducted comparative single-cell transcriptomics and fluorescent microscopy and identified calcium ion (Ca2+) transport/secretion genes and α-carbonic anhydrases that control calcification in a foraminifer. They actively take up Ca2+ to boost mitochondrial adenosine triphosphate synthesis during calcification but need to pump excess intracellular Ca2+ to the calcification site to prevent cell death. Unique α-carbonic anhydrase genes induce the generation of bicarbonate and proton from multiple CO2 sources. These control mechanisms have evolved independently since the Precambrian to enable the development of large cells and calcification despite decreasing Ca2+ concentrations and pH in seawater. The present findings provide previously unknown insights into the calcification mechanisms and their subsequent function in enduring ocean acidification.


Assuntos
Foraminíferos , Água do Mar , Foraminíferos/genética , Foraminíferos/metabolismo , Concentração de Íons de Hidrogênio , Calcificação Fisiológica , Carbonato de Cálcio/metabolismo , Dióxido de Carbono/metabolismo
12.
Sci Rep ; 12(1): 6373, 2022 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-35430588

RESUMO

Large Benthic Foraminifera are a crucial component of coral-reef ecosystems, which are currently threatened by ocean acidification. We conducted culture experiments to evaluate the impact of low pH on survival and test dissolution of the symbiont-bearing species Peneroplis spp., and to observe potential calcification recovery when specimens are placed back under reference pH value (7.9). We found that Peneroplis spp. displayed living activity up to 3 days at pH 6.9 (Ωcal < 1) or up to 1 month at pH 7.4 (Ωcal > 1), despite the dark and unfed conditions. Dissolution features were observed under low Ωcal values, such as changes in test density, peeled extrados layers, and decalcified tests with exposed organic linings. A new calcification phase started when specimens were placed back at reference pH. This calcification's resumption was an addition of new chambers without reparation of the dissolved parts, which is consistent with the porcelaneous calcification pathway of Peneroplis spp. The most decalcified specimens displayed a strong survival response by adding up to 8 new chambers, and the contribution of food supply in this process was highlighted. These results suggest that porcelaneous LBF species have some recovery abilities to short exposure (e.g., 3 days to 1 month) to acidified conditions. However, the geochemical signature of trace elements in the new calcite was impacted, and the majority of the new chambers were distorted and resulted in abnormal tests, which might hinder the specimens' reproduction and thus their survival on the long term.


Assuntos
Antozoários , Foraminíferos , Animais , Calcificação Fisiológica , Recifes de Corais , Ecossistema , Foraminíferos/fisiologia , Concentração de Íons de Hidrogênio , Água do Mar
13.
Diabetes Ther ; 13(3): 517-533, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35199292

RESUMO

AIMS: The CRASH study examined severe hypoglycemia (SH) experiences among people with diabetes (PWD) and caregivers across eight countries. Here we report findings from the Japan cohort, with references to data from the United Kingdom (UK) cohort. MATERIALS AND METHODS: Adults with type 1 (T1DM) or insulin-treated type 2 diabetes mellitus (T2DM) and caregivers (not necessarily related) were recruited from online patient panels. Participants who had experienced at least one SH event in the past 3 years were eligible for study inclusion. Participants completed an online survey regarding their experience with SH, its treatment, and actions during and after an event. RESULTS: Of the 9367 PWD and caregivers from the online patient panels, 8475 participants were ineligible and a total of 53 Japanese participants (35 T1DM, 9 T2DM, 9 caregivers) completed the survey. Most SH incidents occurred at home and were unattended by a healthcare provider. For T1DM, 29% of Japan PWD and 13% of the UK PWD called an ambulance during an SH event; of these, 90% (Japan) and 50% (UK) were transported to hospital. Glucagon use was low (3% Japan and 10% UK for T1DM). Japanese respondents reported emotional impacts of SH, including feeling scared (86% T1DM, 56% T2DM), unprepared (63% T1DM, 78% T2DM), and helpless (60% T1DM, 33% T2DM). Despite the emotional burden, most PWD did not immediately discuss their SH event with a healthcare provider, with the majority (75% T1DM, 71% T2DM) waiting until their next doctor's appointment. CONCLUSION: Conversations around SH between healthcare providers and PWD appear to be insufficient in Japan. An emotional burden of SH was reported by PWD and caregivers. Education regarding the prevention of SH and available treatment options may reduce SH events and improve treatment preparation, while alleviating PWD concerns.

14.
Sci Rep ; 12(1): 2848, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35181716

RESUMO

We clarified the specific micrometric arrangement and nanometric structure of the radiolarian crystalline spines that are not a simple single crystal. A body of the celestite (SrSO4) skeleton of acantharian Acanthometra cf. multispina (Acanthometridae) composed of 20 radial spines having four blades was characterized using microfocus X-ray computed tomography. The regular arrangement of three types of spines was clarified with the connection of the blades around the root of each spine. The surface of the spines was covered with a chitin-based organic membrane to prevent from dissolution in seawater. In the nanometric scale, the mesocrystalline structure that consists of nanoscale grains having distorted single-crystal nature was revealed using scanning- and transmission electron microscopies, electron diffraction, and Raman spectroscopy. The acantharian skeletons have a crystallographically controlled architecture that is covered with a protective organic membrane. These facts are important for penetrating the nature of biogenic minerals.


Assuntos
Rhizaria/ultraestrutura , Esqueleto/anatomia & histologia , Microscopia Eletrônica de Transmissão , Minerais/metabolismo , Sistema Musculoesquelético/anatomia & histologia , Sistema Musculoesquelético/ultraestrutura , Filogenia , Água do Mar , Esqueleto/ultraestrutura , Análise Espectral Raman
15.
Nat Commun ; 13(1): 2417, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35577779

RESUMO

The delivery of genetic material into plants has been historically challenging due to the cell wall barrier, which blocks the passage of many biomolecules. Carbon nanotube-based delivery has emerged as a promising solution to this problem and has been shown to effectively deliver DNA and RNA into intact plants. Mitochondria are important targets due to their influence on agronomic traits, but delivery into this organelle has been limited to low efficiencies, restricting their potential in genetic engineering. This work describes the use of a carbon nanotube-polymer hybrid modified with functional peptides to deliver DNA into intact plant mitochondria with almost 30 times higher efficiency than existing methods. Genetic integration of a folate pathway gene in the mitochondria displays enhanced plant growth rates, suggesting its applications in metabolic engineering and the establishment of stable transformation in mitochondrial genomes. Furthermore, the flexibility of the polymer layer will also allow for the conjugation of other peptides and cargo targeting other organelles for broad applications in plant bioengineering.


Assuntos
Nanotubos de Carbono , DNA/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Nanotubos de Carbono/química , Peptídeos/química , Plantas/genética , Plantas/metabolismo , Polímeros/metabolismo
16.
J Pharmacol Sci ; 117(2): 98-105, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21897055

RESUMO

Transforming growth factor beta-1 (TGF-ß1) plays a critical role in progression of cardiac fibrosis, which may involve intracellular calcium change. We examined effects of efonidipine, a dual T-type and L-type calcium channel blocker (CCB), on TGF-ß1-induced fibrotic changes in neonatal rat cardiac fibroblast. T-type and L-type calcium channel mRNAs were highly expressed in cultured cardiac fibroblasts. TGF-ß1 (5 ng/mL) significantly increased Smad2 phosphorylation and [(3)H]-leucine incorporation, which were attenuated by pretreatment with efonidipine (10 µM). Neither R(-)efonidipine (10 µM), selective T-type CCB, nor nifedipine (10 µM), selective L-type CCB, efficaciously inhibited both TGF-ß1-induced Smad2 phosphorylation and [(3)H]-leucine incorporation. However, both were markedly attenuated by combination of R(-)efonidipine and nifedipine, EDTA, or calcium-free medium. Pretreatment with Smad2 siRNA significantly attenuated [(3)H]-leucine incorporation induced by TGF-ß1. These data suggest that efonidipine elicits inhibitory effects on TGF-ß1- and Smad2-dependent protein synthesis through both T-type and L-type calcium channel-blocking actions in cardiac fibroblasts.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo L/metabolismo , Canais de Cálcio Tipo T/metabolismo , Di-Hidropiridinas/farmacologia , Fibroblastos/efeitos dos fármacos , Nitrofenóis/farmacologia , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Animais , Fibroblastos/metabolismo , Fibrose/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Nifedipino/farmacologia , Compostos Organofosforados/farmacologia , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína Smad2/genética , Transfecção , Fator de Crescimento Transformador beta1/metabolismo
17.
ACS Appl Bio Mater ; 4(6): 5049-5056, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35007053

RESUMO

Photothermal therapy (PTT) using near-infrared (NIR) light is an attractive treatment modality for cancer, in which photothermal agents absorb energy from photons and convert it into thermal energy to lead to cancer cell death. Among the various organic and inorganic materials, single-walled carbon nanotubes (SWCNTs) are promising candidates for NIR photothermal agents due to their strong absorption in this region as well as their high photothermal conversion efficiency. In the development of the SWCNT-based PTT materials, modifications of SWCNTs to offer a stable dispersion for biocompatibility as well as to target the tumor of choice while maintaining their NIR absorption have been required. While modification of SWCNTs through noncovalent methods can be achieved, these modifications can be easily reversed in the body. Contrarily, modifications through covalent attachments, while more desirable, may compromise the NIR absorption characteristics of the SWCNTs. Previously, we reported the development of a synthetic strategy to coat SWCNTs with a cross-linked polymer (i.e., a gel) through a process called CNT Micelle Polymerization and successfully introduced maleimide groups that allowed for postmodification through the ene-thiol reaction without deteriorating the NIR absorption. In this report, we postmodify thiol-containing antibodies (anti-TRP-1, a melanoma specific protein) using maleimide chemistry and find that the SWCNTs conjugated with anti-TRP-1 maintain the characteristic NIR absorption as SWCNTs with dispersion stability. It is estimated that 50 maleimide groups are incorporated in one SWCNT (ca. 280 nm long) and they are modified with 32 TRP-1 fragments. Finally, we successfully use these targeted SWCNTs for the PTT of the melanoma cell line using NIR light (1064 nm; 2 W, 5 min). Our method can be extended to a vast array of specific antibodies as well as other targeting agents.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Antígenos Específicos de Melanoma/imunologia , Melanoma/terapia , Nanotubos de Carbono , Fototerapia , Polietilenoglicóis/administração & dosagem , Animais , Anticorpos Monoclonais/química , Linhagem Celular , Géis , Camundongos , Nanotubos de Carbono/química , Polietilenoglicóis/química
18.
Elife ; 102021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33902812

RESUMO

Some sea slugs sequester chloroplasts from algal food in their intestinal cells and photosynthesize for months. This phenomenon, kleptoplasty, poses a question of how the chloroplast retains its activity without the algal nucleus. There have been debates on the horizontal transfer of algal genes to the animal nucleus. To settle the arguments, this study reported the genome of a kleptoplastic sea slug, Plakobranchus ocellatus, and found no evidence of photosynthetic genes encoded on the nucleus. Nevertheless, it was confirmed that light illumination prolongs the life of mollusk under starvation. These data presented a paradigm that a complex adaptive trait, as typified by photosynthesis, can be transferred between eukaryotic kingdoms by a unique organelle transmission without nuclear gene transfer. Our phylogenomic analysis showed that genes for proteolysis and immunity undergo gene expansion and are up-regulated in chloroplast-enriched tissue, suggesting that these molluskan genes are involved in the phenotype acquisition without horizontal gene transfer.


Assuntos
Clorófitas/fisiologia , Cloroplastos/fisiologia , Gastrópodes/genética , Transferência Genética Horizontal , Simbiose/genética , Animais , Núcleo Celular/genética , Núcleo Celular/fisiologia , Clorófitas/genética , Filogenia
19.
J Pharmacol Exp Ther ; 332(3): 1072-80, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19940106

RESUMO

Treatment with angiotensin II type 1 receptor blockers (ARBs) is the first-line therapy for hypertensive patients with diabetic nephropathy. However, emerging clinical evidence indicates that mineralocorticoid receptor (MR) blockers have blood pressure-independent antiproteinuric effects. We sought to determine whether treatment with an MR blocker, eplerenone, enhances the effects of an ARB, telmisartan, on podocyte injury and proteinuria in type 2 diabetic Otsuka-Long-Evans-Tokushima-Fatty (OLETF) rats. From 20 to 50 weeks old, diabetic OLETF rats showed higher systolic blood pressure (SBP) and urinary protein excretion (U(protein)V) than nondiabetic control Long-Evans-Tokushima-Otsuka rats. At 50 weeks old, OLETF rats also showed glomerular sclerosis and podocyte injury, whereas nephrin and podocin mRNA levels in isolated glomeruli were significantly decreased. Treatment with telmisartan (3 mg/kg/day p.o.) decreased SBP and U(protein)V, increased nephrin and podocin mRNA levels, and attenuated glomerular sclerosis and podocyte injury. Eplerenone (100 mg/kg/day p.o.) did not alter SBP but elicited similar changes in renal parameters. However, greater reductions in U(protein)V and podocyte injury and greater increases in nephrin and podocin mRNA levels were observed in the combination treatment group. Hydralazine (25 mg/kg/day p.o.) decreased SBP but did not alter any renal parameters. These data indicate that MR blockade enhances the SBP-independent antiproteinuric effect of an ARB through inhibiting podocyte injury in type 2 diabetic rats.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Antagonistas de Receptores de Mineralocorticoides , Podócitos/efeitos dos fármacos , Proteinúria/tratamento farmacológico , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Animais , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Benzoatos/farmacologia , Benzoatos/uso terapêutico , Diabetes Mellitus Tipo 2/patologia , Sinergismo Farmacológico , Eplerenona , Peptídeos e Proteínas de Sinalização Intracelular , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/metabolismo , Masculino , Proteínas de Membrana/biossíntese , Podócitos/patologia , Proteinúria/etiologia , Ratos , Ratos Endogâmicos OLETF , Espironolactona/análogos & derivados , Espironolactona/farmacologia , Espironolactona/uso terapêutico , Telmisartan
20.
Histochem Cell Biol ; 133(6): 669-76, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20458492

RESUMO

We previously reported that the blood-brain barrier (BBB) function was deteriorated in vessels located in the hippocampus in stroke-prone spontaneously hypertensive rats (SHRSP). In order to assess whether substances with oxidative stress such as amyloid-beta (Abeta) can be scavenged in the BBB-damaged vessels, we examined the gene expression of representative efflux and influx transporters of Abeta, such as low-density lipoprotein receptor (LDLR), LDL-related protein 1 (LRP1), and the receptor for advanced glycation end product (RAGE) in the hippocampus of SHRSP with the BBB impairment and Wistar Kyoto rats (WKY) without the impairment. Real-time quantitative reverse transcriptase-polymerase chain reaction analysis revealed that LDLR gene expression was increased in the samples of SHRSP compared with those of WKY, while there was no significant difference in LRP1 or RAGE gene expression between SHRSP and WKY. Western blot analysis revealed that the protein expression of LDLR was increased in the samples of SHRSP compared with those of WKY. Immunoelectron microscopic examination revealed that the LDLR expression was seen in the luminal and abluminal cytoplasmic membranes and vesicular structures of the endothelial cells and the cytoplasm of perivascular cells, especially in vessels with immunoreactivity of albumin showing increased vascular permeability. These findings suggest that the expression of LDLR was increased in the hippocampus of SHRSP compared with that of WKY and was seen in the luminal and abluminal cytoplasmic membranes and vesicular structures of endothelial cells, suggesting a role of LDLR in the vessels with BBB impairment.


Assuntos
Barreira Hematoencefálica , Regulação da Expressão Gênica , Ratos Endogâmicos SHR , Receptores de LDL/metabolismo , Acidente Vascular Cerebral , Animais , Barreira Hematoencefálica/patologia , Western Blotting , Modelos Animais de Doenças , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos WKY , Receptores de LDL/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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