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1.
Sci Rep ; 14(1): 10449, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714775

RESUMO

The body temperature of infants at equilibrium with their surroundings is balanced between heat production from metabolism and the transfer of heat to the environment. Total heat production is related to body size, which is closely related to metabolic rate and oxygen consumption. Body temperature control is a crucial aspect of neonatal medicine but we have often struggled with temperature measures. Contactless infrared thermography (IRT) is useful for vulnerable neonates and may be able to assess their spontaneous thermal metabolism. The present study focused on heat oscillations and their cause. IRT was used to measure the skin temperature every 15 s of neonates in an incubator. We analyzed the thermal data of 27 neonates (32 measurements), calculated the average temperature within specified regions, and extracted two frequency components-Components A and B-using the Savitzky-Golay method. Furthermore, we derived an equation describing the cycle-named cycle T-for maintaining body temperature according to body weight. A positive correlation was observed between cycle T and Component B (median [IQR]: 368 [300-506] s). This study sheds light on the physiological thermoregulatory function of newborns and will lead to improved temperature management methods for newborns, particularly premature, low-birth-weight infants.


Assuntos
Regulação da Temperatura Corporal , Termografia , Humanos , Recém-Nascido , Termografia/métodos , Regulação da Temperatura Corporal/fisiologia , Feminino , Masculino , Monitorização Fisiológica/métodos , Temperatura Corporal/fisiologia , Temperatura Cutânea/fisiologia
2.
Biotechnol Bioeng ; 121(6): 1889-1901, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38500437

RESUMO

Microfiltration (MF) is an essential step during biopharmaceutical manufacturing. However, unexpected flux decay can occur. Although the flux decay profile and initial flux are important factors determining MF filterability, predicting them accurately is challenging, as the root cause of unexpected flux decay remains elusive. In this study, the methodology for developing a prediction model of flux decay profiles was established. First, the filtration profiles of different monodisperse polystyrene latex and silica beads of various sizes were evaluated. These results revealed that the size and surface electrostatic properties of the beads affect the flux decay profile. Taking the size and surface electrostatic properties of protein aggregates into account, we constructed a predictive model using model bead filtration profiles. We showed that this methodology was applicable to two different MF filters to predict the flux decay profile of therapeutic proteins. Because our proposed prediction model is based on normalized flux, the initial flux is required to predict the overall filtration profile. Then, we applied the Hagen-Poiseuille equation using sample viscosity values to estimate the initial flux. The developed prediction models can be used for effective MF scale-up assessment during the early stages of process development.


Assuntos
Proteínas , Proteínas/química , Proteínas/metabolismo , Filtração/métodos , Tamanho da Partícula
3.
Pediatr Res ; 95(6): 1536-1542, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38267709

RESUMO

BACKGROUND: We previously reported that hydrogen (H2) gas combined with therapeutic hypothermia (TH) improved short-term neurological outcomes in asphyxiated piglets. However, the effect on seizure burden was unclear. Using amplitude-integrated electroencephalography (aEEG), we compared TH + H2 with TH alone in piglets 24 h after hypoxic-ischemic (HI) insult. METHODS: After a 40-min insult and resuscitation, 36 piglets ≤24 h old were divided into three groups: normothermia (NT, n = 14), TH alone (33.5 ± 0.5 °C, 24 h, n = 13), and TH + H2 (2.1-2.7% H2 gas, 24 h, n = 9). aEEG was recorded for 24 h post-insult and its background pattern, status epilepticus (SE; recurrent seizures lasting >5 min), and seizure occurrence (Sz; occurring at least once but not fitting the definition of SE) were evaluated. Background findings with a continuous low voltage and burst suppression were considered abnormal. RESULTS: The percentage of piglets with an abnormal aEEG background (aEEG-BG), abnormal aEEG-BG+Sz and SE was lower with TH + H2 than with TH at 24 h after HI insult. The duration of SE was shorter with TH + H2 and significantly shorter than with NT. CONCLUSIONS: H2 gas combined with TH ameliorated seizure burden 24 h after HI insult. IMPACT: In this asphyxiated piglet model, there was a high percentage of animals with an abnormal amplitude-integrated electroencephalography background (aEEG-BG) after hypoxic-ischemic (HI) insult, which may correspond to moderate and severe hypoxic-ischemic encephalopathy (HIE). Therapeutic hypothermia (TH) was associated with a low percentage of piglets with EEG abnormalities up to 6 h after HI insult but this percentage increased greatly after 12 h, and TH was not effective in attenuating seizure development. H2 gas combined with TH was associated with a low percentage of piglets with an abnormal aEEG-BG and with a shorter duration of status epilepticus at 24 h after HI insult.


Assuntos
Animais Recém-Nascidos , Eletroencefalografia , Hidrogênio , Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Convulsões , Animais , Hipotermia Induzida/métodos , Suínos , Convulsões/terapia , Hipóxia-Isquemia Encefálica/terapia , Hipóxia-Isquemia Encefálica/fisiopatologia , Modelos Animais de Doenças , Asfixia Neonatal/terapia , Asfixia Neonatal/fisiopatologia , Asfixia Neonatal/complicações , Asfixia/complicações , Asfixia/terapia , Estado Epiléptico/terapia , Estado Epiléptico/fisiopatologia
4.
Sci Rep ; 13(1): 10486, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37380745

RESUMO

Neonatal hypoxic-ischemic encephalopathy (HIE) is a major cause of morbidity and mortality in newborns in both high- and low-income countries. The important determinants of its pathophysiology are neural cells and vascular components. In neonatal HIE, increased vascular permeability due to damage to the blood-brain barrier is associated with seizures and poor outcomes in both translational and clinical studies. In our previous studies, hydrogen gas (H2) improved the neurological outcome of HIE and ameliorated the cell death. In this study, we used albumin immunohistochemistry to assess if H2 inhalation effectively reduced the cerebral vascular leakage. Of 33 piglets subjected to a hypoxic-ischemic insult, 26 piglets were ultimately analyzed. After the insult, the piglets were grouped into normothermia (NT), H2 ventilation (H2), therapeutic hypothermia (TH), and H2 combined with TH (H2-TH) groups. The ratio of albumin stained to unstained areas was analyzed and found to be lower in the H2 group than in the other groups, although the difference was not statistically significant. In this study, H2 therapy did not significantly improve albumin leakage despite the histological images suggesting signs of improvement. Further investigations are warranted to study the efficacy of H2 gas for vascular leakage in neonatal HIE.


Assuntos
Hipóxia-Isquemia Encefálica , Hipóxia , Animais , Suínos , Hipóxia-Isquemia Encefálica/terapia , Albuminas , Barreira Hematoencefálica , Hidrogênio/farmacologia , Hidrogênio/uso terapêutico
5.
Bioorg Med Chem Lett ; 51: 128360, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34537330

RESUMO

Bioconjugation is an important chemical biology research focus, especially in the development of methods to produce pharmaceutical bioconjugates and antibody-drug conjugates (ADCs). In this report, an enzyme-catalyzed conjugation method combined with a chemical reaction was used to modify a native antibody under mild reaction conditions. Our investigation revealed that lipoic-acid ligase (LplA) modifies native IgG1 with biased site-specificity. An intact mass analysis revealed that 98.3% of IgG1 was modified by LplA and possessed at least one molecule of octanocic acid. The average number of modifications per antibody was calculated to be 4.6. Peptide mapping analysis revealed that the modified residues were K225, K249 and K363 in the Fc region, and K30, K76 and K136 in the heavy chain and K39/K42, K169, K188 and K190 in the light chain of the Fab region. Careful evaluation including solvent exposed amino acid analysis suggested that these conjugate sites were not only solvent exposed but also biased by the site-specificity of LplA. Furthermore, antibody fragment conjugation may be able to take advantage of this enzymatic approach. This feasibility study serves as a demonstration for preparing enzymatically modified antibodies with conjugation site analysis.


Assuntos
Imunoconjugados/química , Imunoglobulina G/química , Ligases/química , Ácido Tióctico/química , Humanos , Imunoconjugados/imunologia , Imunoglobulina G/imunologia , Ligases/imunologia , Estrutura Molecular , Ácido Tióctico/imunologia
7.
Mol Ther ; 28(1): 129-141, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31677955

RESUMO

Recent advances in gene therapy technologies have enabled the treatment of congenital disorders and cancers and facilitated the development of innovative methods, including induced pluripotent stem cell (iPSC) production and genome editing. We recently developed a novel non-transmissible and non-integrating measles virus (MV) vector capable of transferring multiple genes simultaneously into a wide range of cells through the CD46 and CD150 receptors. The MV vector expresses four genes for iPSC generation and the GFP gene for a period of time sufficient to establish iPSCs from human fibroblasts as well as peripheral blood T cells. The transgenes were expressed differentially depending on their gene order in the vector. Human hematopoietic stem/progenitor cells were directly and efficiently reprogrammed to naive-like cells that could proliferate and differentiate into primed iPSCs by the same method used to establish primed iPSCs from other cell types. The novel MV vector has several advantages for establishing iPSCs and potential future applications in gene therapy.


Assuntos
Reprogramação Celular/genética , Vetores Genéticos , Genoma Viral/genética , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Vírus do Sarampo/genética , RNA Viral/genética , Animais , Doadores de Sangue , Diferenciação Celular/genética , Fibroblastos/metabolismo , Terapia Genética/métodos , Células HEK293 , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Vírus Sendai/genética , Linfócitos T/metabolismo , Transdução Genética , Transgenes
8.
Acta Parasitol ; 64(2): 418-422, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30977052

RESUMO

INTRODUCTION: Murine Eimeria spp. have been used as effective experimental models of disease instead of large mammalian hosts such as cattle. We here examine drug susceptibility of the uncharacterized murine intestinal protozoan parasite, Eimeria krijgsmanni. MATERIALS AND METHODS: The effectiveness of different treatments against infection of E. krijgsmanni was examined for suppression of oocyst shedding: ST mixture ST mixture, pyrimethamine, Ektecin and toltrazuril. RESULTS: ST mixture and pyrimethamine did not suppress oocyst shedding effectively. Although therapeutic efficacy of Ektecin was demonstrated, the dose required was larger than that for cattle and chickens. Oocyst shedding was only completely suppressed completely by continuous administration of toltrazuril. Furthermore, it was confirmed through morphological examination that early developmental stage zoites appeared in host epithelial cells during and following treatment by toltrazuril, and toltrazuril could not eliminate residual zoites in epithelial cells. CONCLUSION: E. krijgsmanni may be relatively resistant to these anti-coccidian agents and might therefore have different characteristics that differ from other coccidia with regard to drug susceptibility.


Assuntos
Coccidiose/tratamento farmacológico , Coccidiostáticos/uso terapêutico , Eimeria/efeitos dos fármacos , Animais , Coccidiose/parasitologia , Fezes/parasitologia , Feminino , Intestinos/parasitologia , Camundongos , Camundongos Endogâmicos ICR , Oocistos , Contagem de Ovos de Parasitas
9.
Artif Organs ; 42(7): 736-745, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29660790

RESUMO

Ligament reconstruction using a tissue-engineered artificial ligament (TEAL) requires regeneration of the ligament-bone junction such that fixation devices such as screws and end buttons do not have to be used. The objective of this study was to develop a TEAL consisting of elastin-coated polydioxanone (PDS) sutures covered with elastin and collagen fibers preseeded with ligament cells. In a pilot study, a ring-type PDS suture with a 2.5 mm (width) bone insertion was constructed with/without elastin coating (Ela-coat and Non-coat) and implanted into two bone tunnels, diameter 2.4 mm, in the rabbit tibia (6 cases each) to access the effect of elastin on the bond strength. PDS specimens taken together with the tibia at 6 weeks after implantation indicated growth of bone-like hard tissues around bone tunnels accompanied with narrowing of the tunnels in the Ela-coat group and not in the Non-coat group. The drawout load of the Ela-coat group was significantly higher (28.0 ± 15.1 N, n = 4) than that of the Non-coat group (7.6 ± 4.6 N, n = 5). These data can improve the mechanical bulk property of TEAL through extracellular matrix formation. To achieve this TEAL model, 4.5 × 106 ligament cells were seeded on elastin and collagen fibers (2.5 cm × 2.5 cm × 80 µm) prior to coil formation around the elastin-coated PDS core sutures having ball-shape ends with a diameter of 2.5 mm. Cell-seeded and cell-free TEALs were implanted across the femur and the tibia through bone tunnels with a diameter of 2.4 mm (6 cases each). There was no incidence of TEAL being pulled in 6 weeks. Regardless of the remarkable degradation of PDS observed in the cell-seeded group, both the elastic modulus and breaking load of the cell-seeded group (n = 3) were comparable to those of the sham-operation group (n = 8) (elastic modulus: 15.4 ± 1.3 MPa and 18.5 ± 5.7 MPa; breaking load: 73.0 ± 23.4 N and 104.8 ± 21.8 N, respectively) and higher than those of the cell-free group (n = 5) (elastic modulus: 5.7 ± 3.6 MPa; breaking load: 48.1 ± 11.3 N) accompanied with narrowed bone tunnels and cartilage matrix formation. These data suggest that elastin increased the bond strength of TEAL and bone. Furthermore, our newly developed TEAL from elastin, collagen, and ligament cells maintained the strength of the TEAL even if PDS was degraded.


Assuntos
Colágeno/química , Ligamentos Colaterais/citologia , Elastina/química , Polidioxanona/química , Tíbia/cirurgia , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Fenômenos Biomecânicos , Regeneração Óssea , Células Cultivadas , Ligamentos Colaterais/lesões , Ligamentos Colaterais/ultraestrutura , Módulo de Elasticidade , Feminino , Projetos Piloto , Coelhos , Procedimentos de Cirurgia Plástica , Suturas , Tíbia/fisiologia
10.
PLoS Genet ; 13(7): e1006926, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28749988

RESUMO

Mammalian genomes harbor millions of retrotransposon copies, some of which are transpositionally active. In mouse prospermatogonia, PIWI-interacting small RNAs (piRNAs) combat retrotransposon activity to maintain the genomic integrity. The piRNA system destroys retrotransposon-derived RNAs and guides de novo DNA methylation at some retrotransposon promoters. However, it remains unclear whether DNA methylation contributes to retrotransposon silencing in prospermatogonia. We have performed comprehensive studies of DNA methylation and polyA(+) RNAs (transcriptome) in developing male germ cells from Pld6/Mitopld and Dnmt3l knockout mice, which are defective in piRNA biogenesis and de novo DNA methylation, respectively. The Dnmt3l mutation greatly reduced DNA methylation levels at most retrotransposons, but its impact on their RNA abundance was limited in prospermatogonia. In Pld6 mutant germ cells, although only a few retrotransposons exhibited reduced DNA methylation, many showed increased expression at the RNA level. More detailed analysis of RNA sequencing, nascent RNA quantification, profiling of cleaved RNA ends, and the results obtained from double knockout mice suggest that PLD6 works mainly at the posttranscriptional level. The increase in retrotransposon expression was larger in Pld6 mutants than it was in Dnmt3l mutants, suggesting that RNA degradation by the piRNA system plays a more important role than does DNA methylation in prospermatogonia. However, DNA methylation had a long-term effect: hypomethylation caused by the Pld6 or Dnmt3l mutation resulted in increased retrotransposon expression in meiotic spermatocytes. Thus, posttranscriptional silencing plays an important role in the early stage of germ cell development, then transcriptional silencing becomes important in later stages. In addition, intergenic and intronic retrotransposon sequences, in particular those containing the antisense L1 promoters, drove ectopic expression of nearby genes in both mutant spermatocytes, suggesting that retrotransposon silencing is important for the maintenance of not only genomic integrity but also transcriptomic integrity.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA/genética , Células Germinativas/crescimento & desenvolvimento , Proteínas Mitocondriais/genética , Fosfolipase D/genética , Transcrição Gênica , Animais , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Camundongos , Camundongos Knockout , Interferência de RNA , Estabilidade de RNA/genética , RNA Interferente Pequeno/genética , Retroelementos/genética , Espermatócitos/crescimento & desenvolvimento , Testículo/crescimento & desenvolvimento , Testículo/metabolismo , Transcriptoma/genética
11.
J Cardiol Cases ; 8(2): e81-e84, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30546749

RESUMO

An 80-year-old man, who had dilated cardiomyopathy with right ventricular (RV) dilatation, underwent implantable cardioverter defibrillator (ICD) implantation for advanced atrioventricular block and primary prevention of sudden cardiac death. Tined and screw-in leads were placed on the right atrial appendage and RV apex, respectively. Ventricular pacing inhibition was detected after surgery due to oversensing by diaphragmatic myopotential occurring only during deep inspiration. We performed re-surgery and switched the screw-in lead for a tined lead. The diaphragmatic myopotential decreased, thereby improving oversensing by diaphragmatic myopotential and ventricular pacing inhibition. It might be beneficial to use a tined lead when placing the ventricular lead at the RV apex for implantation of a pacemaker or ICD if oversensing of diaphragmatic myopotential is observed using a screw-in lead. .

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