RESUMO
AIMS: During fermentation, the accumulation of acidic products can induce media acidification, which restrains the growth of Bifidobacterium animalis subsp. lactis Bb12 (Bb12). This study investigated the nutrient consumption patterns of Bb12 under acid stress and effects of specific nutrients on the acid resistance of Bb12. METHODS AND RESULTS: Bb12 was cultured in chemically defined medium (CDM) at different initial pH values. Nutrient consumption patterns were analyzed in CDM at pH 5.3, 5.7, and 6.7. The patterns varied with pH: Asp + Asn had the highest consumption rate at pH 5.3 and 5.7, while Ala was predominant at pH 6.7. Regardless of the pH levels (5.3, 5.7, or 6.7), ascorbic acid, adenine, and Fe2+ were vitamins, nucleobases, and metal ions with the highest consumption rates, respectively. Nutrients whose consumption rates exceeded 50% were added individually in CDM at pH 5.3, 5.7, and 6.7. It was demonstrated that only some of them could promote the growth of Bb12. Mixed nutrients that could promote the growth of Bb12 were added to three different CDM. In CDM at pH 5.3, 5.7, and 6.7, it was found that the viable cell count of Bb12 was the highest after adding mixed nutrients, which were 8.87, 9.02, and 9.10 log CFU ml-1, respectively. CONCLUSIONS: The findings suggest that the initial pH of the culture medium affects the nutrient consumption patterns of Bb12. Specific nutrients can enhance the growth of Bb12 under acidic conditions and increase its acid resistance.
Assuntos
Bifidobacterium animalis , Probióticos , Ácidos , Purinas , Nutrientes , Pirimidinas , Concentração de Íons de HidrogênioRESUMO
BACKGROUND: One of the greatest challenges in using Lactobacillus acidophilus as a probiotic is acid stress. The current research aimed to identify substances that help L. acidophilus resist acid stress; this was achieved through assessing its nutrient consumption patterns under various pH conditions. RESULTS: The consumption rates of alanine, uracil, adenine, guanine, niacin, and manganese were consistently higher than 60% for L. acidophilus LA-5 cultured at pH 5.8, 4.9, and 4.4. The consumption rates of glutamic acid + glutamine and thiamine increased with decreasing pH and were higher than 60% at pH 4.9 and 4.4. The viable counts of L. acidophilus LA-5 were significantly increased under the corresponding acidic stress conditions (pH 4.9 and 4.4) through the appropriate addition of either alanine (3.37 and 2.81 mmol L-1), glutamic acid + glutamine (4.77 mmol L-1), guanine (0.13 and 0.17 mmol L-1), niacin (0.02 mmol L-1), thiamine (0.009 mmol L-1), or manganese (0.73 and 0.64 mmol L-1) (P < 0.05). The viable counts of L. acidophilus LA-5 cultured in a medium supplemented with combined nutritional factors was 1.02-1.03-fold of the counts observed in control medium under all acid conditions (P < 0.05). CONCLUSION: Alanine, glutamic acid + glutamine, guanine, niacin, thiamine, and manganese can improve the growth of L. acidophilus LA-5 in an acidic environment in the present study. The results will contribute to optimizing strategies to enhance the acid resistance of L. acidophilus and expand its application in the fermentation industry. © 2024 Society of Chemical Industry.
Assuntos
Lactobacillus acidophilus , Probióticos , Lactobacillus acidophilus/metabolismo , Lactobacillus acidophilus/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Nutrientes/metabolismo , FermentaçãoRESUMO
BACKGROUND: For patients receiving one lung ventilation in thoracic surgery, numerous studies have proved the superiority of lung protective ventilation of low tidal volume combined with recruitment maneuvers (RM) and individualized PEEP. However, RM may lead to overinflation which aggravates lung injury and intrapulmonary shunt. According to CT results, atelectasis usually forms in gravity dependent lung regions, regardless of body position. So, during anesthesia induction in supine position, atelectasis usually forms in the dorsal parts of lungs, however, when patients are turned into lateral decubitus position, collapsed lung tissue in the dorsal parts would reexpand, while atelectasis would slowly reappear in the lower flank of the lung. We hypothesize that applying sufficient PEEP without RM before the formation of atelectasis in the lower flank of the lung may beas effective to prevent atelectasis and thus improve oxygenation as applying PEEP with RM. METHODS: A total of 84 patients scheduled for elective pulmonary lobe resection necessitating one lung ventilation will be recruited and randomized totwo parallel groups. For all patients, one lung ventilation is initiated the right after patients are turned into lateral decubitus position. For patients in the study group, individualized PEEP titration is started the moment one lung ventilation is started, while patients in the control group will receive a recruitment maneuver followed by individualized PEEP titration after initiation of one lung ventilation. The primary endpoint will be oxygenation index measured at T4. Secondary endpoints will include intrapulmonary shunt, respiratory mechanics, PPCs, and hemodynamic indicators. DISCUSSION: Numerous previous studies compared the effects of individualized PEEP applied alone with that applied in combination with RM on oxygenation index, PPCs, intrapulmonary shunt and respiratory mechanics after atelectasis was formed in patients receiving one lung ventilation during thoracoscopic surgery. In this study, we will apply individualized PEEP before the formation of atelectasis while not performing RM in patients allocated to the study group, and then we're going to observe its effects on the aspects mentioned above. The results of this trial will provide a ventilation strategy that may be conductive to improving intraoperative oxygenation and avoiding the detrimental effects of RM for patients receiving one lung ventilation. TRIAL REGISTRATION: www.Chictr.org.cn ChiCTR2400080682. Registered on February 5, 2024.
Assuntos
Ventilação Monopulmonar , Posicionamento do Paciente , Pneumonectomia , Respiração com Pressão Positiva , Atelectasia Pulmonar , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Respiração com Pressão Positiva/métodos , Respiração com Pressão Positiva/efeitos adversos , Ventilação Monopulmonar/métodos , Ventilação Monopulmonar/efeitos adversos , Pneumonectomia/efeitos adversos , Pneumonectomia/métodos , Atelectasia Pulmonar/prevenção & controle , Atelectasia Pulmonar/etiologia , Resultado do Tratamento , Adulto , Pessoa de Meia-Idade , Pulmão/fisiopatologia , Pulmão/cirurgia , Feminino , Masculino , Idoso , Toracoscopia/efeitos adversos , Toracoscopia/métodos , Fatores de Tempo , Adulto Jovem , ChinaRESUMO
The negative effect of photoinduced halide segregation (PIHS) on the properties of hybrid halide perovskites poses a major obstacle for its future commercial application. Therefore, the in-depth understanding of halide-ion segregation and its causes is an urgent and intractable problem. When PIHS reaches a certain threshold, it will aggravate the deterioration of the film surface morphology and form nanoscale cracks. Herein, the formation mechanism and types of cracks are revealed by exploring the stress distribution in the film. Using the femtosecond time-resolved transient absorption spectroscopy, the ultrafast formation of the iodine rich phase is observed, which appears earlier than the bromine rich phase. In addition, the introduction of organic ligand didodecyldimethylammonium bromide can significantly inhibit PIHS and improve the surface morphology of the film, which can promote the device efficiency from 9.63 to 11.20%. This work provides a novel perspective for the exploration of the PIHS.
RESUMO
Objective: Postoperative deep venous thrombosis (DVT) is commonly observed in patients undergoing craniotomy and is associated with a high incidence of pulmonary embolism and poor clinical outcomes. Herein, we investigated the prophylactic effect of DVT of intraoperative intermittent pneumatic compression (IPC) in patients undergoing craniotomy. Methods: A total of 516 patients who underwent elective craniotomy between December 2021 and December 2022 were enrolled in this study. Patients were randomly assigned to the intervention group (received intraoperative IPC) or control group (without IPC). Lower extremity ultrasound was performed on both legs before and after surgery (1 h, 24 h, and 7 days post-intervention). DVT was defined as the visualization of a thrombus within the vein lumen of the leg. Coagulation and platelet function were measured at the start and end of the craniotomy. Results: A total of 504 patients (251 in the intervention group and 253 in the control group) completed the study. Among these patients, 20.4% (103/504) developed postoperative DVT within the first week after surgery, with 16.7% occurring within 24 h. The incidence of postoperative DVT in the intervention group (9.6%, 24/251) was significantly lower than that in the control group (22.9%, 58/253, p < 0.001). Intraoperative IPC reduced the risk of DVT by 64.6% (0.354, 95% CI, 0.223-0.564, p < 0.001). There was no significant difference in coagulation and platelet function between the two groups (all p > 0.05). Conclusion: DVT may develop within 24 h after the craniotomy. Intraoperative application of IPC reduces the incidence of postoperative DVT.
RESUMO
The aim of this study was to investigate the dynamic profile of microorganisms and metabolites in Hainan Trinitario cocoa during a six-day spontaneous box fermentation process. Shotgun metagenomic and metabolomic approaches were employed for this investigation. The potential metabolic functions of microorganisms in cocoa fermentation were revealed through a joint analysis of microbes, functional genes, and metabolites. During the anaerobic fermentation phase, Hanseniaspora emerged as the most prevalent yeast genus, implicated in pectin decomposition and potentially involved in glycolysis and starch and sucrose metabolism. Tatumella, possessing potential for pyruvate kinase, and Fructobacillus with a preference for fructose, constituted the primary bacteria during the pre-turning fermentation stage. Upon the introduction of oxygen into the fermentation mass, acetic acid bacteria ascended to dominant within the microflora. The exponential proliferation of Acetobacter resulted in a decline in taxonomic richness and abundance. Moreover, the identification of novel species within the Komagataeibacter genus suggests that Hainan cocoa may serve as a valuable reservoir for the discovery of unique cocoa fermentation bacteria. The KEGG annotation of metabolites and enzymes also highlighted the significant involvement of phenylalanine metabolism in cocoa fermentation. This research will offer a new perspective for the selection of starter strains and the formulation of mixed starter cultures.
Assuntos
Cacau , Chocolate , Microbiota , Fermentação , Bactérias , Cacau/metabolismoRESUMO
OBJECTIVE: General anesthesia can disturb the hormone levels in surgical patients. Hormone deficiency is one of the major symptoms of craniopharyngioma (CP) in pediatric patients. The aim of this prospective randomized controlled clinical study is to evaluate whether propofol and sevoflurane influence the perioperative hormone levels in these patients and to determine which anesthesia technique causes less impact on hormone levels. MATERIALS: Sixty-four ASA I and II pediatric patients with CP undergoing elective neurosurgery were randomly divided into the sevoflurane group (S group, n = 32) and the propofol group (P group, n = 32). Anesthesia was maintained with sevoflurane and propofol until the end of the operation. Demographic information, operation information and hemodynamic variables were recorded. The levels of hormones were evaluated preoperatively as the baseline (T0), 1h after the beginning of the operation (T1), immediately at the end of the operation (T2) and 72 h postoperatively (T3). RESULTS: There were no significant differences in the two groups in terms of patients' demographics and intraoperative information, such as operation duration, blood loss and transfusion volumes, and fluid infusion volume (P>0.05). In both groups, compared to those at T0, the levels of TSH, FT3, TT3 and ACTH at T1, T2 and T3 were significantly lower. The levels of FSH, PRL and GH at T3 were also significantly lower (P<0.05). The FT3 and TT3 levels of both groups at T2 and T3 were significantly lower than those at T1, but the ACTH level was significantly increased (P<0.05). Compared to the levels at T2, the TSH, FT3, FT4 and ACTH levels of the two groups at T3 were significantly reduced (P<0.05). The baseline hormone levels of both groups were similar (P>0.05). At T1, the FT3, TT3, FT4, TT4 and ACTH levels in the P group were significantly lower than those in the S group (P<0.05). At T2, the TT3 and ACTH levels of the P group were significantly lower than those of the S group (P<0.05) At T3, the TT4 level in the P group was significantly lower than that of the S group (P<0.05). CONCLUSION: Propofol and sevoflurane could reduce the levels of hormones intraoperatively and postoperatively in pediatric patients with craniopharyngioma. However, propofol reduced hormone levels more intensively, mainly intraoperatively. Postoperatively, propofol and sevoflurane had similar inhibition effects on the shift in hormone levels. Therefore, in pediatric patients with craniopharyngioma undergoing neurosurgery, sevoflurane might be the preferred anesthetic because it causes less interruption of hormone levels. However, because of their similar postoperative effects, which long-term effects of sevoflurane or propofol could produce optimal clinical situations? Thus more extensive clinical studies are needed. TRIAL REGISTRATION: Clinical trial registration. This trail was registered at Chinese Clinical Trial Registry (http://www.chictr.org.cn, Jun Xiong) on 28/12/2021, registration number was ChiCTR2100054885.
Assuntos
Anestésicos Inalatórios , Craniofaringioma , Éteres Metílicos , Neoplasias Hipofisárias , Propofol , Humanos , Criança , Propofol/uso terapêutico , Propofol/farmacologia , Sevoflurano , Craniofaringioma/cirurgia , Anestesia Geral , Neoplasias Hipofisárias/cirurgia , Hormônio Adrenocorticotrópico , Tireotropina , Éteres Metílicos/uso terapêutico , Anestésicos Inalatórios/uso terapêuticoRESUMO
Studies have proved that activity and fitness behaviors are closely related to the quality of life and health status of the elderly. However, different intensities of physical activity (PA)-walking, moderate PA, and vigorous PA-have different correlations with the built environment (BE). This study combines the high and low socioeconomic status (SES) of Guangzhou to establish two types of BE models. The physical activity time of 600 elderly people was collected from questionnaires. Through ArcGIS software, 300 m, 500 m, 800 m, and 1000 m buffer zones were identified, and the land use diversity, street design, population density, distance to destination, distance to public transportation-the five Ds of the BE-were measured. SPSS software was adopted to analyze the correlation between the BE and PA. Results: The PA of people living in low-SES areas was more dependent on the BE, whereas the correlation may be limited in high SES areas. Moreover, in low SES areas, walking was negatively correlated with street connectivity; moderate PA was positively correlated with street connectivity and the shortest distance to the subway station, but negatively correlated with the density of entertainment points of interest (POIs). Studying the relevant factors of the environment can propose better strategies to improve the initiative of the elderly to engage in PA.
Assuntos
Planejamento Ambiental , Qualidade de Vida , Idoso , Ambiente Construído , Estudos Transversais , Exercício Físico , Humanos , Características de Residência , CaminhadaRESUMO
Solanum lycopersicum var. cerasiforme accession PI 114490 has broad-spectrum resistance to bacterial spot caused by several species of Xanthomonas. Resistance is quantitatively inherited, and a common quantitative trait locus QTL-11B on chromosome 11 has been identified previously. In this study, the SlPub24 gene was characterized in QTL-11B. SlPub24 in PI 114490 was upregulated by infection with X. euvesicatoria pv. perforans race T3, but its transcription was low in the susceptible line OH 88119 whether or not it was infected by the pathogen. The differential expression of SlPub24 between PI 114490 and OH 88119 was due to great sequence variation in the promoter region. The promoter of SlPub24 in OH 88119 had very low activity and did not respond to pathogen infection. Transgenic lines of OH 88119 overexpressing SlPub24 isolated from PI 114490 showed significantly enhanced resistance, while mutants of Slpub24 generated by CRISPR/Cas9 editing showed more susceptibility to race T3 and to other races. The mutants also showed spontaneous cell death in leaves. The expression of the salicylic acid (SA) pathway gene phenylalanine ammonia-lyase (PAL) and signaling-related genes pathogenesis-related (PR1) and nonexpresser of PR1 (NPR1) were influenced by SlPub24. The content of SA in tomato plants was consistent with the level of SlPub24 expression. Furthermore, SlPUB24 interacted with the cell wall protein SlCWP and could regulate the degradation of SlCWP. The expression levels of SlCWP and SlCWINV1, a cell wall invertase gene, showed opposite patterns during pathogen infection. The activity of SlCWINV1 was lower in mutants than in PI 114490. The results are discussed in terms of the roles of the abovementioned genes, and a potential model for SlPUB24-mediated resistance to bacterial spot is proposed.
RESUMO
The present study aimed to explore the differences in protein and gene expression of Brucella abortus cultured under biofilm and planktonic conditions. The proteins unique to biofilms and planktonic B. abortus were separated by twodimensional (2D) electrophoresis and then identified by matrixassisted laser desorption/ionizationtandem time of flightmass spectrometry (MALDITOF/TOFMS). Highthroughput sequencing and bioinformatic analyses were performed to identify differentially expressed genes between B. abortus cultured under biofilm and planktonic conditions. The proteins and genes identified by proteomic and genomic analyses were further evaluated via western blot and reverse transcriptionquantitative polymerase chain reaction (RTqPCR) analyses. 2D electrophoresis identified 20 differentially expressed protein spots between biofilms and planktonic cells, which corresponded to 18 individual proteins (12 downregulated and 6 upregulated) after MALDITOF/TOFMS analysis, including elongation factor Tu and enolase. RTqPCR analysis revealed that all of the 18 genes were downregulated in biofilms compared with planktonic cells. Western blot analysis identified 9 downregulated and 3 upregulated proteins. Highthroughput sequencing and bioinformatic analyses identified 14 function and pathwayassociated genes (e.g., BAbS19_I14970). RTqPCR analysis of the 14 genes showed that they were upregulated in biofilm compared with in planktonic state. In conclusion, these differentially expressed genes may play important roles in bacterial defense, colonization, invasion, and virulence.
Assuntos
Biofilmes , Brucella abortus/genética , Brucella abortus/metabolismo , Plâncton/citologia , Proteômica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Brucella abortus/isolamento & purificação , Brucella abortus/ultraestrutura , Regulação Bacteriana da Expressão Gênica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Transdução de Sinais/genéticaRESUMO
We sought to assess light characteristics and user acceptability of a prototype Bright Classroom (BC), designed to prevent children's myopia by exposing them to light conditions resembling the outdoors. Conditions were measured throughout the school year in the glass-constructed BC, a traditional classroom (TC) and outdoors. Teachers and children completed user questionnaires, and children rated reading comfort at different light intensities. A total of 230 children (mean age 10.2 years, 57.4% boys) and 13 teachers (36.8 years, 15.4% men) completed questionnaires. The median (Inter Quartile Range) light intensity in the BC (2,540 [1,330-4,060] lux) was greater than the TC (477 [245-738] lux, P < 0.001), though less than outdoors (19,500 [8,960-36,000] lux, P < 0.001). A prominent spectral peak at 490-560 nm was present in the BC and outdoors, but less so in the TC. Teachers and children gave higher overall ratings to the BC than TC, and light intensity in the BC in summer and on sunny days (>5,000 lux) was at the upper limit of children's comfort for reading. In summary, light intensity in the BC exceeds TC, and is at the practical upper limit for routine use. Children and teachers prefer the BC.