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Mycotoxins have the potential to increase the risk of airway or intestinal infection due to their effects on epithelial integrity and function. The bacterium Streptococcus suis (S. suis) is often carried in pigs and can cause outbreaks of invasive disease, leading to sepsis and meningitis in postweaning piglets. In this study, we tested the effect of two Fusarium mycotoxins (deoxynivalenol (DON) and T-2) on the integrity of the intestinal epithelium and their interaction with S. suis. Porcine ileal organoids were exposed to DON and T-2 individually or in combination and co-cultured with or without S. suis. Both DON and T-2 were toxic for ileal organoid monolayers at a concentration of 1 µM but not S. suis, even at a higher concentration of 4 µM. To mimic sub-clinical exposures on farms, DON was tested at a concentration of 0.1 µM and T-2 at a concentration of 0.01 µM. The mycotoxins alone did not affect cell permeability, but in combination with S. suis there was an increase in epithelial permeability. Furthermore, DON and T-2 together decreased the transepithelial electrical resistance and increased bacterial translocation.
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Translocação Bacteriana , Íleo , Organoides , Streptococcus suis , Toxina T-2 , Tricotecenos , Animais , Tricotecenos/toxicidade , Tricotecenos/metabolismo , Íleo/microbiologia , Íleo/efeitos dos fármacos , Íleo/metabolismo , Suínos , Streptococcus suis/efeitos dos fármacos , Streptococcus suis/metabolismo , Organoides/efeitos dos fármacos , Organoides/metabolismo , Translocação Bacteriana/efeitos dos fármacos , Toxina T-2/toxicidade , Mucosa Intestinal/microbiologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacosAssuntos
Fibrilação Atrial , Diabetes Mellitus Tipo 2 , Veias Pulmonares , Recidiva , Inibidores do Transportador 2 de Sódio-Glicose , Fibrilação Atrial/cirurgia , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/tratamento farmacológico , Humanos , Veias Pulmonares/cirurgia , Veias Pulmonares/fisiopatologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Resultado do Tratamento , Ablação por Cateter/efeitos adversos , Fatores de Risco , Frequência Cardíaca/efeitos dos fármacos , Fatores de Tempo , Potenciais de AçãoRESUMO
BACKGROUND: The impact of sodium-glucose cotransporter 2 (SGLT2) inhibitors on the postoperative recurrence of atrial fibrillation (AF) in patients with persistent AF undergoing an initial radiofrequency ablation is not yet established. The objective of this study is to assess the impact of SGLT2 inhibitors on the recurrence of AF after radiofrequency ablation in patients with type 2 diabetes complicated persistent AF. METHODS: A total of 182 patients with type 2 diabetes and persistent AF, who underwent their first radiofrequency ablation for AF at our center, were enrolled and divided into two groups: the SGLT2 inhibitor group and the non-SGLT2 inhibitor group. The main outcome of the follow-up was the postoperative recurrence of AF. RESULTS: A total of 49 participants experienced AF recurrence. The use of SGLT2 inhibitors in patients with type 2 diabetes who underwent AF ablation was associated with a significantly lower risk of AF recurrence (adjusted hazard ratio: 0.65; 95% confidence interval: 0.28-0.83; p < .01). CONCLUSIONS: The use of SGLT2 inhibitors is associated with a decreased risk of arrhythmia recurrence after AF ablation in patients with type 2 diabetes complicated with persistent AF.
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OBJECTIVES: To explore the prognostic influence of weight loss (WL) on young overweight/obesity (OW/OB) individuals with heart failure (HF). METHODS: Heart failure enrollees (younger than 45 years, body mass index [BMI] of ≥25 kg/m2) who received medical treatment at Beijing Chaoyang Hospital, Beijing, China, were classified into 2 groups according to whether they experienced significant WL (≥5% from baseline one year after discharge). One-year occurrence rate of major adverse cardiac events (MACEs) comprising cardiac death and rehospitalization for HF was determined. RESULTS: Of the 191 individuals recruited for this study, 47 had significant WL. The incidence of ischemic heart disease and obstructive sleep apnea syndrome, as well as BMI and blood pressure, were higher in those with significant WL compared to the control group. Although there was no noteworthy discrepancy in the occurrence of cardiac death between the 2 groups, significant WL correlated independently with a lower incidence of HF re-hospitalization (hazard ratio [HR]=0.32, 95% confidence interval [CI]: [0.11-0.91], p=0.032) and overall MACEs (HR=0.37, 95% CI: [0.14-0.94], p=0.036) in young OW/OB individuals with HF. CONCLUSION: Significant WL may correlate with favorable prognosis in OW/OB young HF patients.
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Insuficiência Cardíaca , Obesidade , Sobrepeso , Redução de Peso , Humanos , Insuficiência Cardíaca/terapia , Masculino , Prognóstico , Feminino , Adulto , Sobrepeso/complicações , Sobrepeso/epidemiologia , Obesidade/complicações , Índice de Massa Corporal , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Traditionally Momordica charantia (Bitter gourd) is known for its blood glucose lowering potential. This has been validated by many previous studies based on rodent models but human trials are less convincing and the physiological mechanisms underlying the bioactivity of Bitter gourd are still unclear. The present study compared the effects of whole fruit or stems-leaves from five different Bitter gourd cultivars on metabolic control in adult diabetic obese Göttingen Minipigs. METHODS: Twenty streptozotocin-induced diabetic (D) obese Minipigs (body weight ~85 kg) were subdivided in mildly and overtly D pigs and fed 500 g of obesogenic diet per day for a period of three weeks, supplemented with 20 g dried powdered Bitter gourd or 20 g dried powdered grass as isoenergetic control in a cross-over, within-subject design. RESULTS: Bitter gourd fruit from the cultivars "Palee" and "Good healthy" reduced plasma fructosamine concentrations in all pigs combined (from 450±48 to 423±53 and 490±50 to 404±48 µmol/L, both p<0.03, respectively) indicating improved glycemic control by 6% and 17%. These effects were statistically confirmed in mildly D pigs but not in overtly D pigs. In mildly D pigs, the other three cultivars of fruit showed consistent numerical but no significant improvements in glycemic control. The composition of Bitter gourd fruit was studied by metabolomics profiling and analysis identified three metabolites from the class of triterpenoids (Xuedanoside H, Acutoside A, Karaviloside IX) that were increased in the cultivars "Palee" (>3.9-fold) and "Good healthy" (>8.9-fold) compared to the mean of the other three cultivars. Bitter gourd stems and leaves from the cultivar "Bilai" increased plasma insulin concentrations in all pigs combined by 28% (from 53±6 to 67±9 pmol/L, p<0.03). The other two cultivars of stems and leaves showed consistent numerical but no significant increases in plasma insulin concentrations. The effects on plasma insulin concentrations were confirmed in mildly D pigs but not in overtly D pigs. CONCLUSIONS: Fruits of Bitter gourd improve glycemic control and stems-leaves of Bitter gourd increase plasma insulin concentrations in an obese pig model for mild diabetes. The effects of Bitter gourd fruit on glycemic control seem consistent but relatively small and cultivar specific which may explain the varying results of human trials reported in the literature.
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Diabetes Mellitus , Insulinas , Medicina Tradicional Chinesa , Momordica charantia , Animais , Frutosamina , Frutas , Obesidade , Suínos , Porco MiniaturaRESUMO
BACKGROUND: The visually assessed time difference between the mitral valve and tricuspid valve opening (VMT) score was correlated with the increase of left ventricular filling pressure (LVFP). HYPOTHESIS: We suspected that the VMT score might be a valuable prognostic biomarker for heart failure with mildly reduced ejection fraction (HFmrEF) patients. This study was to evaluate the predictive value of VMT score for 1-year all-cause and cardiovascular disease (CVD)-cause mortality in HFmrEF patients. METHODS: This cohort study enrolled 379 patients aged ≥18 years old with HFmrEF. Univariable and multivariable Cox regression analysis was employed to assess the association between VMT score and all-cause or CVD-cause mortality in HFmrEF patients. Hazards ratio (HR), and 95% confidence interval (CI) were effect sizes. Kaplan-Meier curves showed the survival probability of patients. The area under the curve (AUC) evaluated the prognostic value of the VMT score. RESULTS: The risk of all-cause mortality was increased in HFmrEF patients in the VMT score of 2 (HR = 2.80, 95%CI: 1.04-7.52) and 3 (HR = 4.29, 95%CI: 1.58-11.66). The VMT score of 3 was associated with an increased risk of 1-year CVD-cause mortality in patients with HFmrEF (HR = 7.63, 95%CI: 1.70-34.33). The AUC of VMT score for predicting 1-year all-cause mortality of HFmrEF patients was 0.724, and for predicting 1-year CVD-cause mortality of HFmrEF patients was 0.748. The survival probability of patients with the VMT score < 2 was higher than those with the VMT score of 2 and 3. CONCLUSION: The VMT score might be a reliable prognostic index for 1-year all-cause or CVD-cause mortality of HFmrEF patients.
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Doenças Cardiovasculares , Insuficiência Cardíaca , Humanos , Adolescente , Adulto , Valva Mitral/diagnóstico por imagem , Valva Tricúspide/diagnóstico por imagem , Estudos de Coortes , Prognóstico , Volume Sistólico , Insuficiência Cardíaca/diagnósticoRESUMO
Reduction of post-weaning diarrhoea caused by ETEC is a principal objective in pig farming in terms of welfare benefits. This study determined the effects of genetic susceptibility and dietary strategies targeting inflammation and fimbriae adherence on F4-ETEC shedding and diarrhoea in weaned piglets in an experimental challenge model. A DNA marker test targeting single nucleotide polymorphism 2 (SNP2) identified piglets as heterozygous (SNP2+, susceptible) or homozygous (SNP2-, resistant) to developing F4ac-ETEC diarrhoea. A total of 50 piglets, 25 SNP2+ and 25 SNP2-, were weaned at 30 days of age and equally distributed to different treatments (n = 10): Positive control (PC): piglets fed with a negative control diet and provided with colistin via drinking water; Negative control (NC): piglets fed with a negative control diet; Tall oil fatty acids (TOFA): piglets fed with a negative control diet + 1.0 g TOFA/kg feed; Yeast hydrolysate (YH): piglets fed with a negative control diet + 1.5 g YH/kg feed derived from Saccharomyces cerevisiae; and Combination (COM): piglets fed with a negative control diet + 1.0 g TOFA and 1.5 g YH/kg feed. On day 10 post-weaning, all piglets were infected with F4-ETEC by oral administration. Piglets fed with PC, TOFA, YH or COM had a lower faecal shedding of F4-ETEC than NC piglets (P < 0.001), which was also shorter in duration for PC and TOFA piglets than for NC piglets (P < 0.001). Piglets in PC, TOFA, YH and COM had a shorter diarrhoea duration versus NC when classified as SNP2+ (P = 0.02). Furthermore, PC, TOFA and YH piglets grew more than NC and COM piglets in the initial post-inoculation period (P < 0.001). In addition, the level of faecal F4-ETEC shedding and the percentage of pigs that developed F4-ETEC diarrhoea (72 vs. 32%, P < 0.01) following infection were higher, and the duration of F4-ETEC diarrhoea longer (2.6 vs. 0.6 days, P < 0.001), in SNP2+ piglets than in SNP2- piglets, and led to reduced growth performance (P = 0.03). In conclusion, piglets fed with TOFA, YH or their combination, irrespective of their SNP2 status, are more resilient to F4-ETEC infection. Moreover, SNP2+ piglets show a higher level of F4-ETEC shedding and diarrhoea prevalence than SNP2- piglets, confirming an association between SNP2 and F4ac-ETEC susceptibility.
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Escherichia coli Enterotoxigênica , Óleos de Plantas , Saccharomyces cerevisiae , Animais , Suínos , Polimorfismo de Nucleotídeo Único , Diarreia/genética , Diarreia/veterinária , Ácidos GraxosRESUMO
OBJECTIVE: To evaluate the progression of electrophysiological phenomena in atrial fibrillation (AF) and elucidate the association between the left atrial conduction velocity (LACV) and AF recurrence after pulmonary vein isolation. METHODS: A total of 188 AF patients (121 paroxysmal AF and 67 persistent AF) who underwent PVI for the first time were enrolled in this prospective study. The left atrium was mapped using a 20-pole electrode catheter combined with the CARTO3 system. The conduction distances and conduction times of the left atrium from the Bachmann bundle area to the mitral isthmus were calculated. Anterior, posterior, and septal LACV were calculated as conduction distance divided by conduction time. RESULTS: The anterior, posterior, and septal LACVs in the AF recurrence group were slower than those in the nonrecurrence group (anterior: 0.807 [0.766, 0.848] and 1.048 [1.000, 1.093] m/s, p < .05; posterior: 1.037 [0.991, 1.084] vs. 1.315 [1.249, 1.380] m/s, p < .05; septal: 0.904 [0.862, 0.946] vs. 1.163 [1.107, 1.219] m/s, p < .05). The best cut-off value of anterior LACV for predicting AF recurrence was 0.887 m/s (sensitivity 73.9% and specificity 76.5%). Multivariate analysis showed slow anterior LACV <0.887 m/s was an independent predictor of AF recurrence with an adjusted odds ratio of 1.42 (1.04, 1.94). CONCLUSIONS: Slowing conduction velocity is a predictor of AF recurrence after pulmonary vein isolation.
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Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Ablação por Radiofrequência , Humanos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Estudos Prospectivos , Resultado do Tratamento , Ablação por Cateter/efeitos adversos , Átrios do Coração , Veias Pulmonares/cirurgia , RecidivaRESUMO
Background: To investigate the effect of frailty on the long-term prognosis of elderly patients with acute myocardial infarction (AMI). Methods: The data of 238 AMI patients (aged ≥75 years) were retrospectively reviewed. They were divided into two groups according to the Modified Frailty Index (mFI): frailty group (mFI≥0.27, n=143) and non-frailty group (mFI<0.27, n=95). The major adverse cardiovascular and cerebrovascular events (MACEs) and Kaplan-Meier survival curves of the two groups were compared. Multivariate Cox regression analysis was used to identify the risk factors for MACEs. Results: The frailty group showed a significantly older age as well as a higher N-terminal proB-type natriuretic peptide level, Global Registry of Acute Coronary Events score, and CRUSADE bleeding score compared with the non-frailty group (P<0.05). A significantly greater proportion of patients with combined heart failure, atrial fibrillation, comorbidity, and activities of daily living score of <60 was also observed in the frailty group compared with the non-frailty group (P<0.05). At 36 months after AMI, the frailty group vs the non-frailty group showed a significantly poorer survival (log-rank P=0.005), higher incidence of MACEs (50.35 vs 29.47, P=0.001), higher overall mortality rate (20.98% vs 7.37%, P=0.006), higher 30-day mortality rate (13.99% vs 5.26%, P=0.033), higher major bleeding rate (14.69% vs 5.26, P=0.018), and lower repeat revascularization rate (2.10% vs 8.42%, P=0.03). Frailty, type 2 diabetes, and N-terminal proB-type natriuretic peptide ≥1800 pg/mL were independent risk factors for MACEs. Conclusion: Frailty is an independent risk factor affecting the long-term prognosis of elderly patients with AMI.
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Diabetes Mellitus Tipo 2 , Fragilidade , Infarto do Miocárdio , Intervenção Coronária Percutânea , Idoso , Humanos , Fragilidade/epidemiologia , Estudos Retrospectivos , Atividades Cotidianas , Prognóstico , Fatores de Risco , Peptídeos NatriuréticosRESUMO
The objective of this study was to determine the effect of bitter gourd (BG) leftovers (stems and leaves) as an alternative dietary ingredient on pig performance, carcass characteristics, serum parameters (urea, insulin, and leptin levels), and faecal consistency. Healthy Tempo × Great Yorkshire and Landrace pigs (N = 240; 120 gilts and 120 boars) weighing 25.8 kg (9-10 weeks of age) were randomly assigned to three treatments (eight pens per treatment; each pen with five gilts and five boars). The three treatments consisted of a non-supplemented commercial diet (control; CON) and a CON diet supplemented with 6.5 g/kg BG (BG1) or 13 g/kg BG (BG2). Pigs were fed the experimental diets until slaughter (120 kg body weight; BW). Feed intake was recorded daily and calculated for each experimental phase (i.e., days 0-36, days 36-66, days 66-98, and the overall experimental period). Average daily feed intake (ADFI), average daily gain (ADG), and feed conversion ratio (FCR) were calculated. The frequencies of visiting the feed station and of feeding were recorded daily. Faecal scores (FS) for consistency were measured per pen twice weekly. On the day of slaughter, two pigs per pen (one male and one female) were randomly selected for the measurement of muscle thickness and blood collection. At the slaughterhouse, carcass weight, dressing percentage, back fat thickness, muscle depth, and lean meat percentage were recorded. Data were analysed using ANOVA, with the pen as the experimental unit. Diets BG1 or BG2 did not affect the performance of the pigs, except for a significant decrease in the ADG of the pigs fed the BG2 diet in the feeding period of 50-80 kg. However, no differences in performance were observed in the overall experimental period. Faecal scores, carcass quality, and serum levels of urea, insulin, and leptin were also not affected by the diet. In summary, leftovers (stems and leaves) of BG can be successfully added to the diet of growing-finishing pigs without interfering with performance and carcass characteristics.
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Background: Mounting evidence have indicated that long noncoding RNA (lncRNA) muscleblind like splicing regulator 1 antisense RNA 1 (MBNL1-AS1) play a crucial regulatory role in cardiovascular disease, myocardial infarction (MI) included. In this research, we sought to probe into the biological function and potential mechanism of MBNL1-AS1 in MI. Methods: Cardiomyocytes were treated under hypoxic conditions for 0-12 h. Functional assays including CCK-8 and flow cytometry were performed to assess hypoxia-stimulated cardiomyocyte viability and apoptosis, respectively. Moreover, bioinformatics analysis and mechanical assays were conducted to reveal the competitive endogenous RNA (ceRNA) mechanism of MBNL1-AS1. Results: The upregulation of MBNL1-AS1 was found in hypoxia-stimulated cardiomyocytes. Functionally, the downregulation of MBNL1-AS1 dramatically promoted hypoxia-induced cardiomyocyte viability and inhibited apoptosis. Mechanistically, miR-132-3p bound to MBNL1-AS1 in hypoxia-induced cardiomyocytes, and miR-132-3p directly targeted RAB14, member RAS oncogene family (RAB14) and calmodulin binding transcription activator 1 (CAMTA1). Furthermore, MBNL1-AS1 upregulates the expression of RAB14 and CAMTA1 in hypoxia-stimulated cardiomyocytes via targeting miR-132-3p. Conclusions: The current study revealed the critical role of the MBNL1-AS1/miR-132-3p/RAB14/CAMTA1 axis in MI, indicating MBNL1-AS1 as an innovative therapeutic target for MI.
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MicroRNAs , Infarto do Miocárdio , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Antissenso/genética , RNA Antissenso/metabolismo , Apoptose/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Hipóxia , Proliferação de Células/genética , Proteínas de Ligação ao Cálcio , Transativadores/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas rab de Ligação ao GTP/metabolismoRESUMO
Rett syndrome (RTT) is an X-linked neurodevelopmental disorder caused by loss-of-function heterozygous mutations of methyl CpG-binding protein 2 (MECP2) on the X chromosome in young females. Reactivation of the silent wild-type MECP2 allele from the inactive X chromosome (Xi) represents a promising therapeutic opportunity for female patients with RTT. Here, we applied a multiplex epigenome editing approach to reactivate MECP2 from Xi in RTT human embryonic stem cells (hESCs) and derived neurons. Demethylation of the MECP2 promoter by dCas9-Tet1 with target single-guide RNA reactivated MECP2 from Xi in RTT hESCs without detectable off-target effects at the transcriptional level. Neurons derived from methylation-edited RTT hESCs maintained MECP2 reactivation and reversed the smaller soma size and electrophysiological abnormalities, two hallmarks of RTT. In RTT neurons, insulation of the methylation-edited MECP2 locus by dCpf1-CTCF (a catalytically dead Cpf1 fused with CCCTC-binding factor) with target CRISPR RNA enhanced MECP2 reactivation and rescued RTT-related neuronal defects, providing a proof-of-concept study for epigenome editing to treat RTT and potentially other dominant X-linked diseases.
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Síndrome de Rett , Humanos , Feminino , Síndrome de Rett/genética , Síndrome de Rett/terapia , Epigenoma , Proteína 2 de Ligação a Metil-CpG/genética , Proteína 2 de Ligação a Metil-CpG/metabolismo , Neurônios/metabolismo , Mutação , Heterozigoto , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Oxigenases de Função Mista/uso terapêutico , Proteínas Proto-Oncogênicas/metabolismoRESUMO
BACKGROUND: Infection is the most frequent complication associated with the use of totally implantable venous access port (TIVAP). This retrospective study was conducted to determine the risk factors affecting TIVAP-related infection. METHODS: A total of 1406 patients implanted with TIVAP at our center were included in this retrospective study. Incidence of perioperative infection, patient characteristics and bacteriologic data were retrieved and analyzed. Univariable analyses and multiple logistic regression analyses were used to determine the risk factors. RESULTS: Overall, 72 (5.1%) patients had perioperative infection, and TIVAP was finally removed from 12 (0.85%) patients. There was significantly more hematologic malignancy in the infection group, compared to the non-infection group. Patients with chemotherapy and infection within 30 days before operation also had more infections. There were more inpatients in the infection group than in the non-infection group. The rate of hematoma was higher in the infected patients. Multivariate logistic analysis revealed that hematoma (OR 5.695, p < 0.001), preoperative hospital stay (⩾14d) (OR 2.945, p < 0.001), history of chemotherapy (OR 2.628, p = 0.002), history of infection (within 30 days) (OR 4.325, p < 0.001) were independent risk factor for infection. CONCLUSIONS: This study demonstrated that hematoma, preoperative hospital stay (⩾14d), history of chemotherapy and history of infection (within 30 days) are independent risk factor for all patients.
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Infecções Relacionadas a Cateter , Cateterismo Venoso Central , Humanos , Cateterismo Venoso Central/efeitos adversos , Estudos Retrospectivos , Infecções Relacionadas a Cateter/diagnóstico , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/etiologia , Fatores de Risco , Hematoma/etiologia , Cateteres de Demora/efeitos adversos , Cateteres de Demora/microbiologiaRESUMO
Embedded liquid cooling is a preferred solution for dissipating the heat generated by high-power chips. The cooling capacity and pump power consumption of embedded liquid cooling heat sinks differ significantly between different structures. To achieve an accurate match between cooling capacity and heat dissipation requirements, the selection of a liquid-cooled heat sink should be carefully considered in conjunction with the heat dissipation needs of heat sources in real-world thermal management issues. Based on the manufacturing limitations on chip temperature and microchannel pressure, a composite performance index function was developed to assess the cooling capacity and cooling cost of the heat sink. This allowed for the establishment of an evaluation standard to determine the suitability of embedded liquid cooling and heat sink for the heat source. In this study, the suitability of four microchannel heat sinks with the same feature length and fin volume was evaluated under various thermal load conditions. The results show that the best-suited heat sink changes with variations in the thermal load of the chip. In the example, when the heat source was homogeneous at 100 W, the circular section pin fins have an optimal suitability of 0.928 for Re = 500. When the heat source was a heterogeneous heat source with a power of 100 W, the value of Θ was found to be 0.389. Additionally, the optimal suitability of drop section pin fins for Re = 971.5 was determined to be 0.862.
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A three-dimensional convective heat transfer model of a microchannel pin-fin hybrid heat sink was established. Considering the non-uniform heat generation of 3D stacked chips, the splitting distance of pin-fins was optimized by minimizing the maximum heat sink temperature under different heat fluxes in the hotspot, the Reynolds numbers at the entrance of the microchannel, and the proportions of the pin-fin volume. The average pressure drop and the performance evaluation criteria were considered to be the performance indexes to analyze the influence of each parameter on the flow performance and comprehensive performance, respectively. The results showed that the maximum temperature of the hybrid heat sink attained a minimum value with an increase in the splitting distance. The average pressure drop in the center passage of the microchannel first increased and then decreased. Furthermore, the optimal value could not be simultaneously obtained with the maximum temperature. Therefore, it should be comprehensively considered in the optimization design. The heat flux in the hotspot was positively correlated with the maximum heat sink temperature. However, it had no effect on the flow pressure drop. When the Reynolds number and the pin-fin diameter increased, the maximum heat sink temperature decreased and the average pressure drop of the microchannel increased. The comprehensive performance of the hybrid heat sink was not good at small Reynolds numbers, but it significantly improved as the Reynolds number gradually increased. Choosing a bigger pin-fin diameter and the corresponding optimal value of the splitting distance in a given Reynolds number would further improve the comprehensive performance of a hybrid heat sink.
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BACKGROUND: The palatine tonsils are part of the mucosal immune system and stimulate immune responses through M cell uptake sampling of antigens and bacteria in the tonsillar crypts. Little is known about the development of the tonsillar microbiota and the factors determining the establishment and proliferation of disease-associated bacteria such as Streptococcus suis. In this study, we assessed tonsillar microbiota development in piglets during the first 5 weeks of life and identified the relative importance of maternal and environmental farm parameters influencing the tonsillar microbiota at different ages. Additionally, we studied the effect sow vaccination with a bacterin against S. suis on microbiota development and S. suis colonisation in their offspring. RESULTS: Amplicon sequencing of the 16S rRNA gene V3-V4 region revealed that a diverse tonsillar microbiota is established shortly after birth, which then gradually changes during the first 5 weeks of life without a large impact of weaning on composition or diversity. We found a strong litter effect, with siblings sharing a more similar microbiota compared to non-sibling piglets. Co-housing in rooms, within which litters were housed in separate pens, also had a large impact on microbiota composition. Sow parity and prepartum S. suis bacterin vaccination of sows had weaker but significant associations with microbiota composition, impacting on the abundance of Streptococcus species before and after weaning. Sex and birthweight had limited impact on the tonsillar microbiota, and none of the measured factors had consistent associations with microbiota diversity. CONCLUSIONS: The piglet tonsillar microbiota is established shortly after birth. While microbiota development is associated with both environmental and maternal parameters, weaning has limited impact on microbiota composition. Intramuscular vaccination of sows pre-partum had a significant effect on the tonsillar microbiota composition of their piglets. These findings provide new insights into the mechanisms shaping the tonsillar microbiota.
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Microbiota , Tonsila Palatina , Animais , Animais Recém-Nascidos , Bactérias/genética , Vacinas Bacterianas , Feminino , Lactação , Tonsila Palatina/microbiologia , Gravidez , RNA Ribossômico 16S/genética , Suínos , DesmameRESUMO
The hippocampus is involved in processing a variety of mnemonic computations specifically the spatiotemporal components and emotional dimensions of contextual memory. Recent studies have demonstrated cellular heterogeneity along the hippocampal axis. The ventral hippocampus has been shown to be important in the processing of emotion and valence. Here, we combine transgenic and all-virus based activity-dependent tagging strategies to visualize multiple valence-specific engrams in the vHPC and demonstrate two partially segregated cell populations and projections that respond to appetitive and aversive experiences. Next, using RNA sequencing and DNA methylation sequencing approaches, we find that vHPC appetitive and aversive engram cells display different transcriptional programs and DNA methylation landscapes compared to a neutral engram population. Additionally, optogenetic manipulation of tagged cell bodies in vHPC is not sufficient to drive appetitive or aversive behavior in real-time place preference, stimulation of tagged vHPC terminals projecting to the amygdala and nucleus accumbens (NAc), but not the prefrontal cortex (PFC), showed the capacity drive preference and avoidance. These terminals also were able to change their capacity to drive behavior. We conclude that the vHPC contains genetically, cellularly, and behaviorally segregated populations of cells processing appetitive and aversive memory engrams.
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Hipocampo , Memória , Tonsila do Cerebelo/fisiologia , Hipocampo/fisiologia , Memória/fisiologia , Optogenética , Córtex Pré-Frontal/fisiologiaRESUMO
Postzygotic mutations are acquired in normal tissues throughout an individual's lifetime and hold clues for identifying mutagenic factors. Here, we investigated postzygotic mutation spectra of healthy individuals using optimized ultra-deep exome sequencing of the time-series samples from the same volunteer as well as the samples from different individuals. In blood, sperm, and muscle cells, we resolved three common types of mutational signatures. Signatures A and B represent clock-like mutational processes, and the polymorphisms of epigenetic regulation genes influence the proportion of signature B in mutation profiles. Notably, signature C, characterized by C>T transitions at GpCpN sites, tends to be a feature of diverse normal tissues. Mutations of this type are likely to occur early during embryonic development, supported by their relatively high allelic frequencies, presence in multiple tissues, and decrease in occurrence with age. Almost none of the public datasets for tumors feature this signature, except for 19.6% of samples of clear cell renal cell carcinoma with increased activation of the hypoxia-inducible factor 1 (HIF-1) signaling pathway. Moreover, the accumulation of signature C in the mutation profile was accelerated in a human embryonic stem cell line with drug-induced activation of HIF-1α. Thus, embryonic hypoxia may explain this novel signature across multiple normal tissues. Our study suggests that hypoxic condition in an early stage of embryonic development is a crucial factor inducing C>T transitions at GpCpN sites; and individuals' genetic background may also influence their postzygotic mutation profiles.
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Epigênese Genética , Sêmen , Adulto , Humanos , Hipóxia , Fator 1 Induzível por Hipóxia , Masculino , MutaçãoRESUMO
Chordoma is a rare bone tumor arising from notochordal remnants, but the underlying mechanism remains elusive. By integrated mRNA and microRNA analyses, we found significant downregulation of TGFB3 along with upregulation of its inhibitor, miR-29 family in chordoma comparing with notochord. Somatic copy number gains of miR-29 loci in chordoma highlighted a mechanism of inactivation of TGFB3 signaling in tumor formation. In zebrafish, knockout and knockdown homologous tgfb3 resulted in a chordoma-like neoplasm. On the other hand, Smad7 negative feedback regulation of transforming growth factor-ß (TGF-ß) signaling is retentive in chordoma cell UM-Chor1 despite its disruption in most cancer cells (e.g. A549). Therefore, contrary to other cancers, exogenous TGF-ß activated Smad7 by downregulating miR-182 and inhibited cell migration and invasion in UM-Chor1. Meanwhile, TGF-ß decreased chordoma characteristic protein Brachyury. Altogether, downregulation of TGFB3 causes chordomagenesis, showing a feasible target for therapies. The retention of Smad7 negative regulation may maintain the suppressor role of TGF-ß in chordoma.