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1.
Int J Biol Macromol ; 255: 128004, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37979737

RESUMO

Cellulose nanofibers have been extracted from arecanut palm sheath fibers via mild oxalic acid hydrolysis coupled with steam explosion technique. Cellulose nanofibers with diameter of 20.23 nm were obtained from arecanut palm sheath fibers. A series of robust hydrophobic cellulose nanopapers were fabricated by combining the synergistic effect of surface roughness induced by the successful deposition of zinc oxide (ZnO) nanoflakes and stearic acid modification via a simple and cost-effective method. In this work, agro-waste arecanut palm sheath was employed as a novel source for the extraction of cellulose nanofibers. 2 wt% of ZnO nanoflakes and 1 M concentration of stearic acid were used to fabricate mechanically robust hydrophobic cellulose nanopapers with a water contact angle (WCA) of 134°. During the deposition of zinc oxide nanoflakes on the CNP for inducing surface roughness, a hydrogen bonding interaction is formed between the hydroxyl groups of cellulose nanofibers and the zinc oxide nanoflakes. When this surface roughened CNP was dipped in stearic acid solution. The hydroxyl groups in zinc oxide nanoflakes undergoes esterification reaction with carboxyl groups in stearic acid solution forming an insoluble stearate layer and thus inducing hydrophobicity on CNP. The fabricated hydrophobic cellulose nanopaper displayed a tensile strength of 22.4 MPa and better UV blocking ability which is highly desirable for the sustainable packaging material in the current scenario. Furthermore, the service life of the pristine and modified cellulose nanopapers was predicted using the Arrhenius equation based on the tensile properties obtained during the accelerated ageing studies. The outcome of this study would be broadening the potential applications of hydrophobic and mechanically robust cellulose nanopapers in sustainable packaging applications.


Assuntos
Nanofibras , Óxido de Zinco , Óxido de Zinco/química , Celulose/química , Embalagem de Produtos , Nanofibras/química , Interações Hidrofóbicas e Hidrofílicas
2.
Am J Perinatol ; 2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37399848

RESUMO

OBJECTIVE: The accuracy, timeliness, and reliability of the current methods of heart rate (HR) determination in neonatal resuscitation are debatable, each having its own limitations. We aim to compare three methods of HR assessment: (1) traditional stethoscope, (2) electrocardiogram and traditional stethoscope, and (3) digital stethoscope with loudspeaker amplification of heart sounds. STUDY DESIGN: This was a simulated crossover experiment using a high-fidelity manikin. Each team with a physician, a nurse, and a respiratory therapist performed the resuscitations using the three methods (three different scenarios) in different order. The person controlling the HR via manikin controller was blinded, but the single recorder and the providers were not. RESULTS: Eighteen resuscitations were completed (six teams of three methods each). The time to first HR recording (p < 0.001), total number of HR recorded (p < 0.001), and time to recognize dips in HR was significantly improved in the digital stethoscope group (p = 0.009). CONCLUSION: Use of digital stethoscope with amplification improved documentation of HR and earlier recognition of HR changes. KEY POINTS: · Amplified heartbeats during neonatal resuscitation improved documentation.. · Amplified infant heartbeats resulted in earlier recognition of HR changes (increase or decrease).. · Providers using this method had greater satisfaction..

3.
J Perinatol ; 40(6): 875-880, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31959907

RESUMO

OBJECTIVE: Follow-up of infants from the NICU by neonatologist is limited to premature and complicated infants although parents of infants with advanced gestation may have concerns as well. We compared parental questions of infants < 35 weeks gestation (group A), during virtual telemedicine visits, to ≥35 week infants (group B). STUDY DESIGN: In a retrospective cohort study, questions asked by parents were extracted from the electronic medical record of all infants post discharge from the NICU, after their pediatrician visit. RESULTS: Gestation and birth weight of infants in group A were significantly lower than group B but their stay was longer. There were no significant differences in the number of parents who had questions, between the groups (A 68.1% vs B 67.3%, p = 0.91, 95% CI 0.46-1.99, OR = 0.96). CONCLUSIONS: Telemedicine is a feasible tool for follow-up of NICU infants post discharge. Parents of infants with advanced gestation and weight may benefit from NICU follow-up.


Assuntos
Alta do Paciente , Telemedicina , Assistência ao Convalescente , Seguimentos , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal , Projetos Piloto , Estudos Retrospectivos
4.
Asian Pac J Trop Biomed ; 3(12): 947-53, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24093785

RESUMO

OBJECTIVE: The present study was carried out to investigate the phytochemical constituents, In vitro antioxidant potential and anthelmintic activities of Flacourtia sepiaria Roxb leaves. METHODS: The dried powdered leaves of Flacourtia sepiaria were extracted using petroleum ether, chloroform, ethyl acetate and methanol by a soxhlet extractor and preliminary phytochemical screening was performed using standard protocols. All the extract was evaluated for their potential antioxidant activities using test such as DPPH, superoxide anion radical, hydroxyl radical, nitric oxide radical scavenging abilities, ferrous chelating ability and total phenolic and flavanoid content. Anthelmintic activity of extract was screened in adult Indian earthworm model. RESULTS: Preliminary screening revealed the presence of bioactive compounds especially phenolics, tannins and terpenoids in all extracts. The phenolic and flavanoid content was highest in methanolic extract and lowest in petroleum ether extract. The paralytic (9.46±0.212) and death time (31.43±0.148) of methanolic extract was found to be significant (P<0.05) when compared with paralytic (7.33±0.206) and death time (18.60±0.229) of standard piperazine citrate at 100 mg/mL concentration. CONCLUSIONS: The results of the present study indicate that the leaf extracts of Flacourtia sepiaria exhibited strong antioxidant activity and possess significant anthelmintic activity and thus it is a good source of antioxidant and anthelmintic constituents.


Assuntos
Anti-Helmínticos/farmacologia , Antioxidantes/farmacologia , Compostos Fitoquímicos/química , Extratos Vegetais/química , Salicaceae/química , Animais , Anti-Helmínticos/análise , Antioxidantes/análise , Bioensaio , Humanos , Oligoquetos/efeitos dos fármacos , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Análise de Sobrevida
5.
Pediatr Pulmonol ; 48(2): 146-50, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22644794

RESUMO

In an attempt to determine the risk factors associated with the need for a tracheostomy in extremely low birth weight (ELBW) infants, a retrospective, case control study was conducted (each infant with a tracheostomy [case] was matched to two controls). Medical records were reviewed for patients' characteristics, risk factors for tracheostomy and outcome. During the study period (June 1996 to Dec 2010), 934 ELBW infants were admitted to our institution and nine infants had a tracheostomy and were matched to 18 controls. There were no differences in birth weight (BW) and gestation age (GA) between cases and controls (828.1 ± 136.2 g vs. 822.0 ± 140.9 g [P = 0.91] and 26.6 ± 1.8 weeks vs. 26.5 ± 1.6 weeks [P = 0.88], respectively). In comparison to their controls, infants with a tracheostomy had a higher rate of intubation (median 13 [11-15] vs. 3 [2-5], P ≤ 0.001), a higher rate of total intubation attempts (median 18 [13-21] vs. 5.5 [3-7], P = 0.001), and more days of mechanical ventilation prior to their tracheostomy (mean 100.7 ± 27.7 vs. 29.2 ± 19.8 days [P < 0.001]). Also infants with a tracheostomy had a higher rate of non-congenital upper airway obstruction (55% [5/9] vs. 0% [0/18]; P = 0.001), a higher rate of chronic lung disease (100% [9/9] vs. 5% [1/18]; P < 0.001) and a higher mortality (44% [4/9] vs. 0% [0/18]; P = 0.007) than their controls. In conclusion, chronic lung disease, multiple intubations and intubation attempts, duration of mechanical ventilation, and non-congenital upper airway obstruction are risk factors associated with tracheostomies in ELBW infants.


Assuntos
Obstrução das Vias Respiratórias/epidemiologia , Displasia Broncopulmonar/epidemiologia , Intubação Intratraqueal/estatística & dados numéricos , Traqueostomia/estatística & dados numéricos , Peso ao Nascer , Estudos de Casos e Controles , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Recém-Nascido , Masculino , Respiração Artificial/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Traqueostomia/mortalidade , Estados Unidos/epidemiologia
6.
J Immunol ; 169(7): 3507-18, 2002 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-12244140

RESUMO

After the engagement of Ag receptor, most of the Th cells for their optimal activation require a second (costimulatory) signal provided by the APCs. We demonstrate the isolation and characterization of a 99- to 105-kDa protein (B2), from LPS-activated B cell surface, and its function as a Th2-specific costimulatory molecule. Appearance of B2 as a single entity on two-dimensional gel electrophoresis and as a distinct peak in reverse-phase HPLC ascertains the fact that B2 is homogeneous in preparation. Electron microscopy as well as competitive binding studies reveal that (125)I-labeled B2 specifically binds anti-CD3-activated T cell surface and also competes with its unlabeled form. Internal amino acid sequences of B2 are found to be identical with stress protein gp96. The identity of B2 as gp96 is also revealed by immunological characterization and by confocal microscopic colocalization studies of B2 and gp96 on LPS-activated B cells. Confocal imaging studies also demonstrate that gp96 can be induced on B cell surface without association of MHC molecules. Furthermore, the novel role of gp96 in Th cell proliferation skewing its differentiation toward Th2 phenotype has also been established. Ab-mediated blocking of gp96-induced signaling not only abrogates in vitro proliferation of CD4(+) T cells, but also diminishes the secretion of Th2-specific cytokines. Notably, the expression of CD91 (receptor of gp96/B2) is up-regulated on anti-CD3-activated Th cells and also found to be present on Th1 and Th2 subsets.


Assuntos
Antígenos de Neoplasias/fisiologia , Linfócitos B/imunologia , Epitopos de Linfócito T/imunologia , Proteínas de Choque Térmico/fisiologia , Ativação Linfocitária/imunologia , Glicoproteínas de Membrana/fisiologia , Células Th2/imunologia , Sequência de Aminoácidos , Animais , Antígenos de Neoplasias/isolamento & purificação , Antígenos de Neoplasias/metabolismo , Linfócitos B/metabolismo , Células Cultivadas , Feminino , Proteínas de Choque Térmico/isolamento & purificação , Proteínas de Choque Térmico/metabolismo , Lipopolissacarídeos/farmacologia , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/biossíntese , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Glicoproteínas de Membrana/isolamento & purificação , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Ligação Proteica/imunologia , Células Th2/metabolismo , Células Tumorais Cultivadas
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