Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 51
Filtrar
1.
Molecules ; 29(9)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38731440

RESUMEN

Microdroplet-based fluidic systems have the advantages of small size, short diffusion time, and no cross-contamination; consequently, droplets often provide a fast and precise reaction environment as well as an analytical environment for individual molecules. In order to handle diverse reactions, we developed a method to create organic single-micron droplets (S-MDs) smaller than 5 µm in diameter dispersed in silicone oil without surfactant. The S-MD generation microflow device consists of a mother droplet (MoD) generator and a tapered separation channel featuring multiple side channels. The tapered channel enhanced the shear forces to form tails from the MoDs, causing them to break up. Surface treatment with the fluoropolymer CYTOP protected PDMS fluid devices from organic fluids. The tailing separation of methanol droplets was accomplished without the use of surfactants. The generation of tiny organic droplets may offer new insights into chemical separation and help study the scaling effects of various chemical reactions.

2.
Molecules ; 29(2)2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38257311

RESUMEN

This review presents a comprehensive evaluation for the manufacture of organic molecules via efficient microfluidic synthesis. Microfluidic systems provide considerably higher control over the growth, nucleation, and reaction conditions compared with traditional large-scale synthetic methods. Microfluidic synthesis has become a crucial technique for the quick, affordable, and efficient manufacture of organic and organometallic compounds with complicated characteristics and functions. Therefore, a unique, straightforward flow synthetic methodology can be developed to conduct organic syntheses and improve their efficiency.

3.
Anal Chem ; 95(44): 16107-16114, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37877901

RESUMEN

Environmental microorganisms possess enzymes that can digest macromolecules such as agarose into smaller molecules that can be utilized for growth. These enzymes could be valuable for the effective utilization of global resources. However, since most of the microorganisms on Earth remain uncultured, there is significant untapped enzymatic potential in nature. Therefore, it is necessary to develop innovative tools and strategies for exploring these enzymatic resources. To address this, we developed a method for screening microbial cells that secrete hydrogel-degrading enzymes using deformability-based microfluidic microdroplet sorting. In this method, microbial cells are encapsulated as single cells in water-in-oil (W/O) microdroplets with a hydrogel whose shape becomes deformable as the hydrogel is progressively degraded into smaller molecules. Screening is achieved using a microfluidic device that passively sorts the deformed W/O microdroplets. Using this method, we successfully sorted agarose-containing microdroplets, encapsulating single bacterial cells that hydrolyzed agarose. This method can be used to screen various hydrogel-degrading microbial cells.


Asunto(s)
Hidrogeles , Microfluídica , Microfluídica/métodos , Sefarosa , Bacterias , Agua
4.
Intern Med ; 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37743510

RESUMEN

A 74-year-old man experienced diplopia, generalized muscle weakness, and acute respiratory failure. He was diagnosed with Lambert-Eaton myasthenic syndrome (LEMS) and treated with immunotherapy, but no improvement was observed, and additional symptoms, including central apnea and hallucinations, appeared. Subsequent serum and cerebrospinal fluid (CSF) analyses confirmed the presence of GABAB receptor antibodies, indicating the coexistence of autoimmune encephalitis. Although there were no findings of malignancy, it is highly likely that occult small-cell lung carcinoma was present. When atypical symptoms occur in patients with LEMS, it is important to consider the possibility of concomitant autoimmune encephalitis.

5.
Micromachines (Basel) ; 14(4)2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37421123

RESUMEN

The efficient synthesis of amino acid Schiff base copper(II) complexes using a microfluidic device was successfully achieved. Schiff bases and their complexes are remarkable compounds due to their high biological activity and catalytic function. Conventionally, products are synthesized under reaction conditions of 40 °C for 4 h using a beaker-based method. However, in this paper, we propose using a microfluidic channel to enable quasi-instantaneous synthesis at room temperature (23 °C). The products were characterized using UV-Vis, FT-IR, and MS spectroscopy. The efficient generation of compounds using microfluidic channels has the potential to significantly contribute to the efficiency of drug discovery and material development due to high reactivity.

6.
Pediatr Emerg Care ; 39(7): 507-510, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37318851

RESUMEN

OBJECTIVES: In 2016, brief resolved unexplained events (BRUEs) were proposed as alternative concepts to apparent life-threatening event (ALTE). The clinical utility of managing ALTE cases according to the BRUE classification is controversial. To verify the clinical utility of the BRUE criteria, we evaluated the proportion of ALTE patients who met and those who did not meet the BRUE criteria and assessed the diagnoses and outcomes of each group. METHODS: We retrospectively investigated patients with ALTE younger than 12 months who visited the emergency department of the National Center for Child Health and Development from April 2008 to March 2020. The patients were classified into the higher-risk and lower-risk BRUE groups; however, those who did not meet the BRUE criteria were classified into the ALTE-not-BRUE group. We evaluated the diagnoses and outcomes of each group. Adverse outcomes included death, recurrence, aspiration, choking, trauma, infection, convulsions, heart disease, metabolic disease, allergies, and others. RESULTS: Over the period of 12 years, a total of 192 patients were included, among which 140 patients (71%) were classified into the ALTE-not-BRUE group, 43 (22%) into the higher-risk BRUE group, and 9 (5%) into the lower-risk BRUE group. Adverse outcomes occurred in 27 patients in the ALTE-not-BRUE group and 10 patients in the higher-risk BRUE group. No adverse outcome occurred in the lower-risk BRUE group. CONCLUSIONS: Many of the patients with ALTE were classified into the ALTE-not-BRUE group, suggesting that replacing ALTE with BRUE is difficult. Although patients classified as lower-risk BRUE showed no adverse outcomes, there were only a few of them. In the pediatric emergency medicine setting, the BRUE risk classification may be beneficial for certain patients.


Asunto(s)
Obstrucción de las Vías Aéreas , Evento Inexplicable, Breve y Resuelto , Enfermedades del Recién Nacido , Recién Nacido , Niño , Humanos , Lactante , Estudios Retrospectivos , Factores de Riesgo
7.
Micromachines (Basel) ; 14(5)2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37241650

RESUMEN

In this study, we developed a comb-shaped microfluidic device that can efficiently trap and culture a single cell (bacterium). Conventional culture devices have difficulty in trapping a single bacterium and often use a centrifuge to push the bacterium into the channel. The device developed in this study can store bacteria in almost all growth channels using the flowing fluid. In addition, chemical replacement can be performed in a few seconds, making this device suitable for culture experiments with resistant bacteria. The storage efficiency of microbeads that mimic bacteria was significantly improved from 0.2% to 84%. We used simulations to investigate the pressure loss in the growth channel. The pressure in the growth channel of the conventional device was more than 1400 PaG, whereas that of the new device was less than 400 PaG. Our microfluidic device was easily fabricated by a soft microelectromechanical systems method. The device was highly versatile and can be applied to various bacteria, such as Salmonella enterica serovar Typhimurium and Staphylococcus aureus.

8.
Acute Med Surg ; 10(1): e827, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37056485

RESUMEN

Both coronavirus disease 2019 (COVID-19) and heat stroke have symptoms of fever or hyperthermia and the difficulty in distinguishing them could lead to a strain on emergency medical care. To mitigate the potential confusion that could arise from actions for preventing both COVID-19 spread and heat stroke, particularly in the context of record-breaking summer season temperatures, this work offers new knowledge and evidence that address concerns regarding indoor ventilation and indoor temperatures, mask wearing and heat stroke risk, and the isolation of older adults. Specifically, the current work is the second edition to the previously published guidance for handling heat stroke during the COVID-19 pandemic, prepared by the "Working group on heat stroke medical care during the COVID-19 epidemic," composed of members from four organizations in different medical and related fields. The group was established by the Japanese Association for Acute Medicine Heatstroke and Hypothermia Surveillance Committee. This second edition includes new knowledge, and conventional evidence gleaned from a primary selection of 60 articles from MEDLINE, one article from Cochrane, 13 articles from Ichushi, and a secondary/final selection of 56 articles. This work summarizes the contents that have been clarified in the prevention and treatment of infectious diseases and heat stroke to provide guidance for the prevention, diagnosis, and treatment of heat stroke during the COVID-19 pandemic.

10.
Micromachines (Basel) ; 14(3)2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36985113

RESUMEN

We developed a microfluidic device that enables selective droplet extraction from multiple droplet-trapping pockets based on dielectrophoresis. The device consists of a main microchannel, five droplet-trapping pockets with side channels, and drive electrode pairs appropriately located around the trapping pockets. Agarose droplets capable of encapsulating biological samples were successfully trapped in the trapping pockets due to the difference in flow resistance between the main and side channels. Target droplets were selectively extracted from the pockets by the dielectrophoretic force generated between the electrodes under an applied voltage of 500 V. During their extraction from the trapping pockets, the droplets and their contents were exposed to an electric field for 400-800 ms. To evaluate whether the applied voltage could potentially damage the biological samples, the growth rates of Escherichia coli cells in the droplets, with and without a voltage applied, were compared. No significant difference in the growth rate was observed. The developed device enables the screening of encapsulated single cells and the selective extraction of target droplets.

11.
Acute Med Surg ; 10(1): e820, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36816452

RESUMEN

Aim: The study aimed to determine the current status of face mask use, deep body temperature measurement, and active cooling in patients suffering from heat stroke and heat exhaustion in Japan. Methods: This was a prospective, observational, multicenter study using data from the Heatstroke STUDY 2020-2021, a nationwide periodical registry of heat stroke and heat exhaustion patients. Based on the Bouchama heatstroke criteria, we classified the patients into two groups: severe and mild-to-moderate. We compared the outcomes between the two groups and reclassified them into two subgroups according to the severity of the illness, deep body temperature measurements, and face mask use. Cramer's V was used to determine the effect sizes for a comparison between groups. Results: Almost all patients in this study were categorized as having degree III based on the Japanese Association for Acute Medicine heatstroke criteria (JAAM-HS). However, the severe group was significantly worse than the mild-to-moderate group in outcomes like in-hospital death and modified Rankin Scale scores, when discharged. Heat strokes had significantly higher rates of active cooling and lower mortality rates than heat stroke-like illnesses. Patients using face masks often use them during labor, sports, and other exertions, had less severe conditions, and were less likely to be young male individuals. Conclusions: It is suggested that severe cases require a more detailed classification of degree III in the JAAM-HS criteria, and not measuring deep body temperature could have been a factor in the nonperformance of active cooling and worse outcomes.

12.
Antibiotics (Basel) ; 12(1)2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36671291

RESUMEN

We developed two multiplex polymerase chain reactions (PCRs) for the detection of extended-spectrum ß-lactamases (ESBLs), plasmid-mediated AmpC ß-lactamases, aac(6')-Ib gene, and integrase genes (intI1, intI2, and intI3) in class 1, 2, and 3 integrons in Gram-negative bacteria. We evaluated the PCRs using 109 Gram-negative isolates from non-organic (ANO) and organic (AO) vegetables and fruits. Screening of ANO substances identified five SHV, one TEM-1, one CTX-M, 20 AmpC-CS, and two intI1 positives. DNA sequencing revealed CTX-M in Pantoea spp. was blaRANH-2, a plasmid-mediated CTX-M related ESBL gene only found in Rahnella spp. Of the 20 AmpC-CS positives, 10 were CMY/MIR/ACT/EC (3 new variants), eight were ACT, one was AZECL, and one was new Pseudomonas-related AmpC family. Screening of AO substances identified 11 SHV, two TEM-1, three CTX-M (one OXY-2, two CTX-M-14/-15), two OXA-9, 13 AmpC-CS and one intI1 positives. The 13 AmpC-CS positives were five CMY/MIR/ACT/EC, three ACT, one MOX-12 variant, and four ADC (one ADC-25 and three new variants). We developed a rapid, easy-to-perform, low-cost, and reliable multiplex PCR system for screening clinically relevant ß-lactamases and integrons in Gram-negative bacteria. We showed the prevalence of ESBLs and AmpC ß-lactamases among our panel of ampicillin-resistant Gram-negative strains and detection of NDM and OXA carbapenemases.

13.
Nat Commun ; 14(1): 27, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-36631460

RESUMEN

The Stroop effect is a classical, well-known behavioral phenomenon in humans that refers to robust interference between language and color information. It remains unclear, however, when the interference occurs and how it is resolved in the brain. Here we show that the Stroop effect occurs during perception of color-word stimuli and involves a cross-hemispheric, excitatory-inhibitory loop functionally connecting the lateral prefrontal cortex and cerebellum. Participants performed a Stroop task and a non-verbal control task (which we term the Swimmy task), and made a response vocally or manually. The Stroop effect involved the lateral prefrontal cortex in the left hemisphere and the cerebellum in the right hemisphere, independently of the response type; such lateralization was absent during the Swimmy task, however. Moreover, the prefrontal cortex amplified cerebellar activity, whereas the cerebellum suppressed prefrontal activity. This fronto-cerebellar loop may implement language and cognitive systems that enable goal-directed behavior during perceptual conflicts.


Asunto(s)
Encéfalo , Corteza Prefrontal , Humanos , Test de Stroop , Tiempo de Reacción/fisiología , Encéfalo/fisiología , Corteza Prefrontal/fisiología , Cerebelo , Imagen por Resonancia Magnética
14.
BMC Oral Health ; 22(1): 460, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36319994

RESUMEN

BACKGROUND: The antioxidant and anti-inflammatory effects of resveratrol have been reported previously. Particularly, monomeric trans-resveratrol has been demonstrated to produce positive effects in various pathological processes. We reported previously that resveratrol dimer-rich melinjo extract, among others, caused bone healing, decreased local oxidative damage, and activated antioxidants nuclear factor erythroid 2-related factor 2 (Nrf2) pathways in a mouse model of experimentally induced periodontitis (EP). This study aimed to compare the bone-healing effects of the resveratrol monomer to the resveratrol dimer (gnetin C found in melinjo seed extract) in a model of EP and investigate the involvement of Nrf2 for effects of either form of resveratrol. METHODS: EP was induced experimentally in mice by placement of a 9 - 0 silk ligature around the left second molar. Mice received 10 mg/kg of either resveratrol monomer or dimer intraperitoneally on day 15 after induction of EP. The bone level around the ligated teeth was measured over time, and levels of proinflammatory cytokines and oxidative stress were measured in the periodontal tissues around the ligated teeth. RESULTS: Resveratrol dimer induced greater periodontal bone healing as compared to that related to use of the resveratrol monomer. It appears that healing of periodontal bone in either group was likely related to master regulation of antioxidant nuclear factor erythroid 2-related factor 2 (Nrf2) significantly. Downregulation of IL-1ß, a proinflammatory cytokine was also demonstrated in the resveratrol dimer group. CONCLUSION: Our results showed that administration of resveratrol in either dimer form or the monomeric form reduced periodontal bone loss with greater inhibition of bone loss being demonstrated in the dimer group as compared to the monomer group and that these effects were related in all likelihood to decreased oxidative stress and hence reduction in local inflammation.


Asunto(s)
Pérdida de Hueso Alveolar , Periodontitis , Ratones , Animales , Resveratrol , Factor 2 Relacionado con NF-E2 , Antioxidantes/farmacología , Periodontitis/metabolismo , Modelos Animales de Enfermedad , Citocinas/metabolismo
15.
Case Rep Neurol ; 14(2): 326-333, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36160654

RESUMEN

A 64-year-old man presented with left upper limb weakness and dysesthesia for 4 months. Magnetic resonance imaging demonstrated swelling from the 6th-8th left cervical nerve roots to the left brachial plexus. The serum IgG4 level was elevated (762.7 mg/dL). 18F-FDG-PET showed high uptake in the mediastinal lymph nodes, and biopsy revealed infiltration of IgG4-positive plasma cells. We diagnosed IgG4-related neuropathy, and steroid therapy administration improved the symptoms. IgG4-related disease should be considered in the differential diagnosis of peripheral nerve swellings. If biopsy of the disordered nerves is difficult, lymph nodes or other organs should be considered.

16.
Chemistry ; 28(62): e202202284, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-35880578

RESUMEN

We describe the synthesis and characterization of a photoactivated boron-based Lewis acid catalyst based on a cage-shaped triphenolic ligand with three pyrenylmethyl moieties. The obtained cage-shaped borate functioned as a photoactivated Lewis acid catalyst thanks to the flexible three pyrenylmethyl moieties. The deformation of the cage-shaped scaffold driven by intramolecular excimer formations of the pyrenes is a critical factor in realizing the photoactivation. Mannich-type reactions and glycosylations significantly were accelerated under 370 nm light irradiations. It is noteworthy that various glycosyl fluorides, which are not easily activated in photocatalytic systems due to their high C-F bond stability, are activated by the photoimproved catalytic activity of the catalyst.


Asunto(s)
Boratos , Ácidos de Lewis , Ácidos de Lewis/química , Glicosilación , Catálisis , Boro
17.
DEN Open ; 2(1): e59, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35310719

RESUMEN

Objective: To evaluate patient acceptability and bowel preparation efficacy of sodium picosulfate-magnesium citrate (PICOPREP) for colonoscopy. Methods: A questionnaire survey regarding the patient acceptability of bowel preparation agent PICOPREP was administered to 54 patients, and its efficacy was evaluated using the Ottawa Bowel Preparation Scale (OBPS). Results: Eighteen (33.3%) participants reported that PICOPREP is very easy to drink, 30 (55.5%) easy, four (7.4%) acceptable, one (1.9%) difficult, and one (1.9%) very difficult. The flavor was very good as reported by eight (14.8%) participants, good by 25 (46.3%), neutral by 20 (37.0%), bad by one (1.9%), and very bad by none. The number of patients who requested PICOPREP was 42 (77.7%), indicating its high acceptability. Evaluation of the OBPS score showed that the rectosigmoid colon had significantly better polyethylene glycol (PEG) scores than PICOPREP, but the entire colon did not show a significant difference between PICOPREP and PEG scores (1.09 ± 0.65 vs. 1.17 ± 0.76, p = 0.632 in the right colon; 0.48 ± 0.52 vs. 0.72 ± 0.66, p = 0.079 in the mid colon, 0.93 ± 0.49 vs. 0.63 ± 0.52, p = 0.012 in the rectosigmoid colon, and 3.28 ± 1.70 vs. 3.20 ± 1.90, p = 0.836 in the entire colon). Conclusion: PICOPREP is considered as one of the important options due to its good patient acceptability and high efficacy similar to PEG.

18.
Ann Biomed Eng ; 49(12): 3676-3684, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34608582

RESUMEN

Amelotin (AMTN) is a protein that is expressed during the maturation of dental enamel and has important role in enamel hydroxyapatite mineralization. However, it is not well understood whether AMTN has a strong mineral-promoting ability in bone. In this study, the effect of AMTN on bone healing was investigated using mice calvarial defect model in vivo, and the expression of bone marker genes and cell proliferation were investigated to clarify the role of AMTN in bone mineralization using mouse osteogenic cells (MC3T3-E1) in vitro. Collagen membranes, with or without recombinant human (rh) AMTN, were applied to calvarial defects created on the parietal bones of C57BL/6N mice. Microcomputed tomography and histological observation revealed that the defect largely filled with mineralized tissue by the rhAMTN-containing membrane in eight weeks. Moreover, CD31 positive cells were observed in the newly formed mineralized tissue and around the rhAMTN-containing membrane. In the presence of rhAMTN, the expression of the Spp1 gene in MC3T3-E1 cells significantly increased within ten days in an osteoinductive medium. Moreover, rhAMTN significantly enhanced MC3T3-E1 cell proliferation. These findings indicate that AMTN positively influences bone repair by promoting hydroxyapatite mineralization.


Asunto(s)
Proteínas del Esmalte Dental/farmacología , Cráneo/efectos de los fármacos , Cráneo/fisiopatología , Cicatrización de Heridas/efectos de los fármacos , Animales , Proliferación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Masculino , Ratones Endogámicos BALB C , Osteoblastos/fisiología , Cráneo/diagnóstico por imagen , Cráneo/lesiones , Microtomografía por Rayos X
19.
Chem Asian J ; 16(20): 3118-3123, 2021 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-34487429

RESUMEN

The synthesis and isolation of atrane-type molecules 1E+ (E=Si, Ge, or Sn) having a cationic group 14 elemental center are reported. The cations 1E+ act as hard and soft Lewis superacids, which readily interact with various hard and soft Lewis basic substrates. The rigid atrane framework stabilizes the localized positive charge on the elemental center and assists the formation of the well-defined highly coordinated states of 1E+ . The cations were applied to the hydrodefluorination, Friedel-Crafts reaction, alkyne cyclization, and carbonyl reduction as Lewis acid catalysts. Most notably, [1Si][ClO4 ] exhibits unique chemoselectivity that depends on a solvent in the competitive reaction of silyl enol ether with a mixture of benzaldehyde dimethyl acetal and benzaldehyde. Our findings indicate the potential of hard and soft Lewis superacids in organic synthesis.

20.
Molecules ; 26(12)2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-34204558

RESUMEN

In recent years, research on the application of microdroplets in the fields of biotechnology and chemistry has made remarkable progress, but the technology for the stable generation of single-micrometer-scale microdroplets has not yet been established. In this paper, we developed an efficient and stable single-micrometer-scale droplet generation device based on the fragmentation of droplet tails, called "tail thread mode", that appears under moderate flow conditions. This method can efficiently encapsulate microbeads that mimic cells and chemical products in passively generated single-micrometer-scale microdroplets. The device has a simple 2D structure; a T-junction is used for droplet generation; and in the downstream, multi-branch channels are designed for droplet deformation into the tail. Several 1-2 µm droplets were successfully produced by the tail's fragmentation; this continuous splitting was induced by the branch channels. We examined a wide range of experimental conditions and found the optimal flow rate condition can be reduced to one-tenth compared to the conventional tip-streaming method. A mold was fabricated by simple soft lithography, and a polydimethylsiloxane (PDMS) device was fabricated using the mold. Based on the 15 patterns of experimental conditions and the results, the key factors for the generation of microdroplets in this device were examined. In the most efficient condition, 61.1% of the total droplets generated were smaller than 2 µm.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...