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In recent years, carbon-based CsPbI2 Br perovskite solar cells (PSCs) have attracted more attention due to their low cost and good stability. However, the power conversion efficiency (PCE) of carbon-based CsPbI2 Br PSCs is still no more than 16%, because of the defects in CsPbI2 Br or at the interface with the electron transport layer (ETL), as well as the energy level mismatch, which lead to the loss of energy, thus limiting PCE values. Herein, a series of cadmium halides are introduced, including CdCl2 , CdBr2 and CdI2 for dual direction thermal diffusion treatment. Some Cd2+ ions thermally diffuse downward to passivate the defects inside or on the surface of SnO2 ETL. Meanwhile, the energy level structure of SnO2 ETL is adjusted, which is in favor of the transfer of electron carriers and blocking holes. On the other hand, part of Cd2+ and Cl- ions thermally diffuse upward into the CsPbI2 Br lattice to passivate crystal defects. Through dual direction thermal diffusion treatment by CdCl2 , CdI2 and CdBr2 , the performance of devices has been significantly improved, and their PCE has been increased from 13.01% of the original device to 14.47%, 14.31%, and 13.46%, respectively. According to existing reports, 14.47% is one of the highest PCE of carbon-based CsPbI2 Br PSCs with SnO2 ETLs.
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In this study, as-is (ca. 12% moisture by mass) and hydrated (50% water by mass) granules of waxy potato (WP), waxy wheat (WW), waxy maize, normal maize, and high-amylose maize (HAM) starches were investigated by using small-angle neutron and X-ray scattering (SANS and SAXS), wide-angle X-ray scattering, and ultra-small-angle neutron scattering. The SANS and SAXS data were fitted using the two-phase stacking model of alternating crystalline and amorphous layers. The partial crystalline lamellar structures inside the growth rings of granules were analyzed based on the inter-lamellar distances, thicknesses of the crystalline lamellae and amorphous layers, thickness polydispersities, and water content in each type of layer. Despite having a longer average chain length of amylopectin, the WP and HAM starches, which had B-type allomorph, had a shorter inter-lamellar distance than the other three starches with A-type allomorph. The WP starch had the most uniform crystalline lamellar thickness. After hydration, the amorphous layers were expanded, resulting in an increase of inter-layer distance. The low-angle intensity upturn in SANS and SAXS was attributed to scattering from interfaces/surfaces of larger structures, such as growth rings and macroscopic granule surfaces. Data analysis methods based on model fitting and 1D correlation function were compared. The study emphasizedâowing to inherent packing disorder inside granulesâthat a comprehensive analysis of different parameters was essential in correlating the microstructures with starch properties.
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Amilosa , Almidón , Amilosa/química , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Almidón/química , Amilopectina/química , Agua/químicaRESUMEN
BACKGROUND: Postoperative pain and anxiety are two common factors influencing patient's recovery. Benefits and safety in the use of sedative agents after abdominal operations to improve recovery are not well known. The present study is to evaluate the efficacy and safety of dexmedetomidine use in this population. METHODS: A prospective randomized controlled trial of 145 patients undergoing abdominal operations was conducted in the Surgical Intensive Care Unit of Jinling Hospital between October and December 2015. Thirty-two patients were excluded, and 113 were included and divided into the experimental group (59 patients) receiving dexmedetomidine and analgesics for 72 h after abdominal operations, and the control group (54 patients) receiving only analgesics. Postoperative pain, inflammatory response, recovery of gastrointestinal function, adverse events, and sedation level were analyzed. RESULTS: Pain scores, assessed by Prince Henry Pain Scale (PHPS), in the experimental group were significantly lower than in the control group on the first (1.53 vs. 2.07, p ≤ 0.01), second (1.07 vs. 1.63, p ≤ 0.01), and third day (1.08 vs. 1.82, p = 0.01). Time to defecation was 0.60 days shorter in the experimental group than the control group (2.51 vs. 3.11, p = 0.01). There was no significant difference between inflammatory responses in the two groups (p > 0.05). Both groups had similar blood pressure, heart rate, prevalence of bradycardia, and hypotension requiring interventions (p > 0.05). CONCLUSIONS: The addition of dexmedetomidine to analgesia after abdominal operations is safe and could enhance gastrointestinal function recovery and pain control when monitored carefully. The capacity of dexmedetomidine to attenuate inflammatory responses requires further investigation.
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Abdomen/cirugía , Dexmedetomidina/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios ProspectivosAsunto(s)
Acné Vulgar/etiología , Infecciones por Coronavirus/transmisión , Máscaras/efectos adversos , Neumonía Viral/transmisión , Adulto , Betacoronavirus , COVID-19 , Infecciones por Coronavirus/epidemiología , Femenino , Humanos , Masculino , Pandemias , Neumonía Viral/epidemiología , SARS-CoV-2RESUMEN
Berberine, an isoquinoline alkaloid derived from many medicinal plants, has been extensively used to treat various gastrointestinal diseases. In the present study, we investigated whether berberine could ameliorate intestinal mucosal barrier damage induced by peritoneal air exposure for 3 h. Peritoneal air-exposure rats received 100, 150, and 200 mg/kg berberine orally via gavage four times before and after surgery. Blood and terminal ileum samples were collected 24 h after surgery. The serum D-lactate levels were determined using an enzyme-linked immunosorbent assay (ELISA) kit. Intestinal permeability was determined by measuring the intestinal clearance of fluorescein isothiocyanate (FITC)-dextran (FD4). Intestinal inflammation was assessed by measuring myeloperoxidase activity. Intestinal histopathology was also assessed. The results revealed that berberine decreased the serum D-lactate level, intestinal FD4 clearance, and myeloperoxidase activity. Edema and inflammation were reduced by berberine in the intestinal mucosa and submucosa, and the Chiu's scores, indices of intestinal mucosal injury, also decreased in the berberine-treated group. In addition, berberine exerted these protective effects in a dose-dependent manner, with a significant difference from the control group at doses of 150 and 200 mg/kg. The results suggest that berberine could ameliorate intestinal mucosal barrier damage induced by peritoneal air exposure, which is linked to its anti-inflammatory activity. Berberine may be a promising treatment for intestinal mucosal barrier damage in open abdominal surgery.
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Antiinflamatorios/uso terapéutico , Berberina/uso terapéutico , Mucosa Intestinal/efectos de los fármacos , Aire , Animales , Antiinflamatorios/farmacología , Berberina/farmacología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Periodo Intraoperatorio , Ácido Láctico/sangre , Masculino , Peritoneo/cirugía , Permeabilidad , Peroxidasa/metabolismo , Ratas , Ratas Sprague-DawleyRESUMEN
Ginsenoside Rb1 (GRb1), one of the principle active components of Panax ginseng, has been reported to reduce inflammation in various diseases. In the present study, we investigated whether GRb1 has an anti-inflammatory effect on postoperative ileus (POI) and further contributes to the recovery of gastrointestinal motility. POI was induced in rats by intestinal manipulation. The POI rats received 5, 10 and 20 mg/kg GRb1 orally via gavage four times before and after surgery. Gastrointestinal motility was assessed by charcoal transport. Systemic inflammation was assessed by serum tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6 and IL-10 concentrations, whereas intestinal inflammation was assessed by the activity of myeloperoxidase, and concentrations and gene expression of TNF-α, IL-1ß, IL-6 and IL-10 in the ileum tissue. The results revealed that GRb1 increased rat gastrointestinal transit with POI. The increased levels of systemic and intestinal inflammatory parameters in POI rats were also reduced by GRb1. In addition, GRb1 reduced systemic and intestinal inflammation and increased the gastrointestinal transit of POI rats in a dose-dependent manner, and with signiï¬cance at doses of 10 and 20 mg/kg. These results suggest that GRb1 has a potent anti-inflammatory effect on POI and further contributes to the recovery of gastrointestinal motility. GRb1 may be a promising treatment for POI prophylaxis.
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Antiinflamatorios/uso terapéutico , Ginsenósidos/uso terapéutico , Ileus/tratamiento farmacológico , Complicaciones Posoperatorias/tratamiento farmacológico , Animales , Antiinflamatorios/farmacología , Citocinas/sangre , Citocinas/genética , Tránsito Gastrointestinal/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Ginsenósidos/farmacología , Íleon/metabolismo , Ileus/sangre , Masculino , Peroxidasa/metabolismo , Complicaciones Posoperatorias/sangre , ARN Mensajero/metabolismo , Ratas Sprague-DawleyRESUMEN
Pulmonary changes in veno-venous extracorporeal membrane oxygenation (VV-ECMO) are rarely determined. We compared the contribution of VV-ECMO and cannulation based on the observation of pulmonary inflammatory reaction and parenchymal construction in a porcine model of low tidal volume (VT ) ventilation. We also evaluated the effect of adding continuous renal replacement therapy (CRRT) to the ECMO circuit, because CRRT is known to reduce systemic cytokine release induced by VV-ECMO. A total of 18 pigs undergoing low-VT ventilation were randomly divided into three groups (group 1, cannulation; group 2, VV-ECMO; group 3, VV-ECMO + CRRT) and studied for 24 h. Hemodynamic and ventilation parameters were recorded. We assessed plasma and alveolar cytokines, expression of pulmonary inflammatory genes, histopathological grading, and ultrastructural changes of the lungs. During the process, inspiratory volume increased and PaO2 decreased in group 1. Systemic tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6) levels increased at 2 h in group 2 and partly decreased in group 3. At 24 h, the levels of bronchoalveolar lavage fluid, TNF-α, and IL-6 in group 2 were remarkably higher than those in groups 1 and 3. Pulmonary mRNA expression of cytokines did not differ between the groups. We observed an increased score of pulmonary pathological findings in pro-inflammatory cell infiltration and interstitial thickening of the lungs in group 2. The epithelium of the blood-air barrier after VV-ECMO was swollen. In group 3, the pulmonary parenchyma and blood-air barrier were well preserved. We concluded that in a porcine model of low-VT ventilation, both VV-ECMO and VV-ECMO in combination with CRRT provided adequate oxygenation and carbon dioxide removal. Compared with VV-ECMO alone, VV-ECMO in combination with CRRT better preserved the lung parenchyma by eliminating systemic cytokines.
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Oxigenación por Membrana Extracorpórea/efectos adversos , Neumonía/terapia , Terapia de Reemplazo Renal/métodos , Animales , Femenino , Hemodinámica/fisiología , Interleucina-6/metabolismo , Pulmón/metabolismo , Pulmón/ultraestructura , Masculino , Neumonía/etiología , Porcinos , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
BACKGROUND: The pathogenesis of postoperative ileus (POI) is complex. The present study was designed to investigate the effects of peritoneal air exposure on the POI intestinal inflammation and the underlying mechanism. METHODS: Sprague-Dawley rats were randomized into five groups (6/group): the control group, the sham group, and three exposure groups with peritoneal air exposure for 1, 2, or 3 h. At 24 h after surgery, we analyzed the gastrointestinal transit, the serum levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, and IL-10, the myeloperoxidase activity, and the levels of TNF-α, IL-1ß, IL-6, and IL-10 in the ileum and colon. The oxidant and antioxidant levels in the ileum and colon were analyzed by measuring malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and total antioxidant capacity (T-AOC). RESULTS: Peritoneal air exposure caused an air-exposure-time-dependent decrease in the gastrointestinal transit. The length of peritoneal air exposure is correlated with the severity of both systemic and intestinal inflammations and the increases in the levels of MDA, SOD, GSH-Px, and T-AOC. CONCLUSIONS: The length of peritoneal air exposure is proportional to the degree of intestinal paralysis and the severity of intestinal inflammation, which is linked to the oxidative stress response.
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Ileus/etiología , Ileus/metabolismo , Inflamación/complicaciones , Inflamación/metabolismo , Peritoneo/inmunología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/metabolismo , Animales , Glutatión Peroxidasa/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Masculino , Malondialdehído/metabolismo , Ratas , Ratas Sprague-Dawley , Superóxido Dismutasa/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
BACKGROUND/AIMS: In critically ill patients, gastrointestinal function plays an important role in multiple organ dysfunction syndrome. Patients suffering from acute lower gastrointestinal dysfunction need to be performed a temporary fecal diversion after the failure of conservative treatment. This study aims to determine which type of fecal diversion is associated with better clinical outcomes in critically ill patients. METHODOLOGY: Data of critically ill patients requiring surgical decompression following acute lower gastrointestinal dysfunction between January 2008 and June 2013 were retrospectively analyzed. Comparison was made between ileostomy group and colostomy group regarding the stoma-related complications and the recovery after stoma creation. RESULTS: 63 patients consisted of temporary ileostomy group (n = 35) and temporary colostomy group (n = 28) were included in this study. First bowel movement and length of enteral nutrition intolerance after fecal diversion were both significantly shorter in the ileostomy group than in the colostomy group (1.70 ± 0.95 vs. 3.04 ± 1.40; p < 0.001 and 3.96 ± 2.84 vs. 8.12 ± 7.05; p = 0.009). In comparison of the complication rates, we found a significantly higher incidence of dermatitis (31.43% vs. 7.14%; p = 0.017), hypokalemia (25.71 vs. 3.57; p = 0.017) and hypocalcemia (28.57 vs. 7.14; p = 0.031), and slightly lower incidence of stoma prolapse (0% vs. 10.71%; p = 0.082) in the ileostomy group than in the colostomy group. CONCLUSIONS: Both procedures provide an effective defunctioning of the distant gastrointestinal tract with a low complication incidence. We prefer a temporary ileostomy to temporary colostomy for acute lower gastrointestinal dysfunction in critically ill patients.
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Colostomía , Descompresión Quirúrgica/métodos , Enfermedades Gastrointestinales/cirugía , Ileostomía , Adulto , Colostomía/efectos adversos , Enfermedad Crítica , Descompresión Quirúrgica/efectos adversos , Defecación , Nutrición Enteral , Femenino , Enfermedades Gastrointestinales/diagnóstico , Enfermedades Gastrointestinales/etiología , Enfermedades Gastrointestinales/fisiopatología , Humanos , Ileostomía/efectos adversos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Recuperación de la Función , Estudios Retrospectivos , Factores de Tiempo , Resultado del TratamientoRESUMEN
High-amylose maize starch (69.3 % amylose) was debranched to increase the level of linear molecules and enhance the formation of spherulites. Debranched high-amylose maize starch (25 %, w/w) was heated to 180 °C in a Parr reactor followed by crystallization at different temperatures between 25 and 150 °C. The objectives of this study were to investigate the effects of crystallization temperature on the yield, morphology, structure, crystallinity, and digestibility of the spherulites formed. When the crystallization temperature was 150 °C, spherulites with negative birefringent sign were formed. High crystallization temperature caused molecular degradation and the degree of degradation was severe at 150 °C, resulting in relatively short chain amylose (DP < 150). When crystallized at 25 to 120 °C, spherulites with strong positive birefringence were produced. The long chain amylose was attributed to the positive birefringence. All spherulites had a predominant B-type crystalline structure. The spherulites with negative birefringence showed a lower degree of crystallinity and lower resistance to enzyme digestion, but all the spherulites with positive birefringence had a high resistant starch content (89-94 %). α-Amylase was not able to penetrate inside the spherulites as revealed by the confocal laser scanning microscopic images.
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Amilosa , Cristalización , Zea mays , Zea mays/química , Amilosa/química , Almidón/química , Temperatura , HidrólisisRESUMEN
This study aimed to enhance the resistance of bread to gastrointestinal digestion by partially substituting wheat flour with starch spherulites. Three types of starch spherulites, specifically A-type (exhibiting an A-type crystalline pattern with mostly positive birefringence), B(-)-type (B-type crystalline with negative birefringence), and B(+)-type (B-type crystalline with positive birefringence), were investigated. The A-, B(-)-, and B(+)-type spherulites showed significantly higher resistant starch contents of 63.5, 63.8, and 89.2 %, respectively, compared to the control wheat flour (7.4 %). The melting temperatures of A-type and B(+)-type spherulites were notably higher than those of the control wheat flour, suggesting the potential preservation of certain enzyme-resistant starch during the baking process. The partial substitution of wheat flour with spherulites resulted in a denser crumb structure, increased bread hardness and chewiness, and a pale brown color in the case of B(+)-type spherulite. However, these variations in physicochemical properties did not significantly impact consumer acceptability. Remarkably, in bread containing A- or B(+)-type spherulite, residual ordered spherulite structures were present after baking, as confirmed by differential scanning calorimetry. This resulted in significantly lower digestibility during in vitro gastrointestinal digestion. These findings are useful for the rational design of bread with sustained glucose release during gastrointestinal digestion.
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Pan , Digestión , Harina , Almidón , Triticum , Pan/análisis , Almidón/química , Almidón/metabolismo , Digestión/fisiología , Harina/análisis , Triticum/química , Tracto Gastrointestinal/metabolismo , HumanosRESUMEN
Leaf shape is a vital agronomic trait that affects plant and canopy architecture, yield, and other production attributes of upland cotton. Compared with normal leaves, lobed leaves have potential advantages in improving canopy structure and increasing cotton yield. A chromosomal introgression segment from Gossypium barbadense L. conferring sub-okra leaf shape to Gossypium hirsutum L. was identified on chromosome D01. To determine the effects of this transferred sub-okra leaf shape on the leaf anatomical characteristics, photosynthesis-related traits, and yield of short-season cotton, we performed a field experiment with three sets of near-isogenic lines carrying okra, sub-okra, and normal leaf shape in Lu54 (L54) and Shizao 2 (SZ2) backgrounds. Compared with normal leaves, sub-okra leaves exhibited reduced leaf thickness and smaller leaf mass per area; moreover, the deeper lobes of sub-okra leaves improved the plant canopy structure by decreasing leaf area index by 11.24%-22.84%. Similarly, the intercepted PAR rate of lines with sub-okra leaf shape was also reduced. The chlorophyll content of sub-okra leaves was lower than that of okra and normal leaf shapes; however, the net photosynthetic rate of sub-okra leaves was 8.17%-29.81% higher than that of other leaf shapes at most growth stages. Although the biomass of lines with sub-okra leaf shape was less than that of lines with normal leaves, the average first harvest yield and total yield of lines with the sub-okra leaf shape increased by 6.36% and 5.72%, respectively, compared with those with normal leaves. Thus, improvements in the canopy structure and photosynthetic and physiological characteristics contributed to optimizing the light environment, thereby increasing the yield of lines with sub-okra leaf shape. Our results suggest that the sub-okra leaf trait from G. barbadense L. may have practical applications for cultivating short-season varieties with high photosynthetic efficiency, and improving yield, which will be advantageous for short-season varieties.
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To determine the suitable planting density and row spacing of short-season cotton suitable for machine picking in the Yellow River Basin of China, we conducted a two-year field experiment in Dezhou during 2018-2019. The experiment followed a split-plot design, with planting density (82500 plants·hm-2 and 112500 plants·hm-2) as the main plots and row spacing (equal row spacing of 76 cm, wide-narrow row spacing of 66 cm+10 cm, equal row spacing of 60 cm) as the subplots. We examined the effects of planting density and row spacing on growth and development, canopy structure, seed cotton yield and fiber quality of short-season cotton. The results showed that plant height and LAI under high density treatment were significantly greater than those under low density treatment. The transmittance of the bottom layer was significantly lower than under low density treatment. Plant height under 76 cm equal row spacing was significantly higher than that under 60 cm equal row spacing, while that under wide-narrow row spacing (66 cm +10 cm) was significantly smaller than that under 60 cm equal row spacing in peak bolling stage. The effects of row spacing on LAI varied between the two years, densities, and growth stages. On the whole, the LAI under the wide-narrow row spacing (66 cm+10 cm) was higher, with the curve declining gently after the peak, and it was higher than that in the two cases of equal row spacing in the harvest time. The change in transmittance of the bottom layer presented the opposite trend. Density, row spacing, and their interaction had significant effects on seed cotton yield and its components. In both years, seed cotton yield was the highest (3832 kg·hm-2 in 2018, 3235 kg·hm-2 in 2019) under wide-narrow row spacing (66 cm+10 cm), and it was more stable at high densities. Fiber quality was less affected by density and row spacing. To sum up, the optimal density and row spacing of short-season cotton were as follows: density with 112500 plants·hm-2 and wide-narrow row spacing (66 cm+10 cm).
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Ríos , Semillas , Estaciones del Año , Biomasa , GossypiumRESUMEN
Pyrodextrins were prepared by heating waxy maize starch for 4 h at pH 3 & 150 °C, pH 3 & 170 °C, and pH 2 & 150 °C. Those pyrodextrins were soluble in water at 25 °C, but insoluble in glycerol. The objectives of this study were to investigate dissolution of the pyrodextrins in glycerol/water mixtures, and to determine how crystallinity and birefringence of the pyrodextrins were affected by swelling. Pyrodextrins prepared at pH 3 & 170 °C and pH 2 & 150 °C either dissolved or swelled little in glycerol/water mixtures at 25 °C. In contrast, the pyrodextrin prepared at pH 3 & 150 °C, which showed the least depolymerization, swelled in 40% glycerol to increase granule diameter ~80%. Despite that significant swelling, those swollen granules still displayed a Maltese cross pattern but were amorphous, demonstrating the separation of loss of crystallinity from loss of birefringence.
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Almidón , Zea mays , Birrefringencia , Glicerol , Solubilidad , Agua , CerasRESUMEN
Bt proteins are crystal proteins produced by Bacillus thuringiensis (Bt) in the early stage of spore formation that exhibit highly specific insecticidal activities. The application of Bt proteins primarily includes Bt transgenic plants and Bt biopesticides. Transgenic crops with insect resistance (via Bt)/herbicide tolerance comprise the largest global area of agricultural planting. After artificial modification, Bt insecticidal proteins expressed from Bt can be released into soils through root exudates, pollen, and plant residues. In addition, the construction of Bt recombinant engineered strains through genetic engineering has become a major focus of Bt biopesticides, and the expressed Bt proteins will also remain in soil environments. Bt proteins expressed and released by Bt transgenic plants and Bt recombinant strains are structurally and functionally quite different from Bt prototoxins naturally expressed by B. thuringiensis in soils. The former can thus be regarded as an environmentally exogenous substance with insecticidal toxicity that may have potential ecological risks. Consequently, biosafety evaluations must be conducted before field tests and production of Bt plants or recombinant strains. This review summarizes the adsorption, retention, and degradation behavior of Bt insecticidal proteins in soils, in addition to their impacts on soil physical and chemical properties along with soil microbial diversity. The review provides a scientific framework for evaluating the environmental biosafety of Bt transgenic plants, Bt transgenic microorganisms, and their expression products. In addition, prospective research targets, research methods, and evaluation methods are highlighted based on current research of Bt proteins.
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The objectives of this study were to debranch waxy maize starch by pullulanase, produce spherulites with different crystalline structures and birefringent properties by controlling crystallization conditions and determine how their structures were correlated with their digestibilities. The spherulites formed in water or 50% ethanol at 4 °C without mixing had a B-type crystalline structure. The birefringence sign was not uniform for the spherulites formed in water at 4 °C; some spherulites displayed negative birefringence. However, positive birefringence was observed for the spherulites formed in 50% ethanol at 4 °C, indicating starch chains were radially arranged. The spherulites crystallized in water at 50 °C followed by further crystallization at 4 °C had a predominate A-type crystalline pattern with positive birefringence in some particles, the highest resistant starch content (73.0%) and the highest degree of crystallinity (76%).
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Almidón/química , Zea mays/química , Amilopectina/química , BirrefringenciaRESUMEN
In the AOAC Method 2002.02 assay for resistant starch (RS), the enzyme-resistant starch is solubilized by cold 2 M KOH, so that it can be converted enzymatically to glucose. However, cross-linked phosphorylated (CLP) starch is not soluble in cold 2 M KOH and therefore cannot be assayed directly. In this study, the enzyme-resistant starch from CLP starch was treated by 1) the directions in AOAC Method 996.11for total starch assay using hot DMSO or cold KOH; 2) two back-to-back incubations with thermal-stable α-amylase in a boiling water bath; and 3) a KOH treatment followed by two back-to-back incubations with thermal-stable α-amylase in a boiling water bath. In the last approach, the alkaline was neutralized with HCl, and the salt was removed by centrifugation. More than 95% of the RS from the CLP starch was converted to glucose. This improved method is recommended to directly determine RS in CLP starch.
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Pullulanase is able to debranch amylopectin and result in higher resistant starch (RS) content in waxy maize starch. Different levels of pullulanase have been used to debranch waxy maize starch in the literature, but the changes of structure during debranching are unknown. In this study, waxy maize starch (25% solids) was cooked and debranched with different levels of pullulanase. The structure of waxy maize starch during debranching was investigated and the digestibility of the debranched products was measured. When pullulanase activity was increased, more amylopectin was debranched in same debranching time, and the degree of crystallinity and the RS content were increased. With longer debranching time, more linear chains were cleaved and crystallized to B-type crystalline structure at 25⯰C. More than 80% of waxy maize starch could be debranched by pullulanase. After the debranched starches were crystallized at 25⯰C for 24â¯h, the RS content was increased to 70.7%.
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BACKGROUND: Bacillus thuringiensis (Bt) crops have been cultivated at a large scale over the past several decades, which have raised concern about unintended effects on natural environments. Microbial communities typically contain numerous rare taxa that make up the majority of community populations. However, the response of dominant and rare taxa for fungal diversity to the different root environments of Bt plants remains unclear. RESULTS: We quantified fungal population sizes and community composition via quantitative PCR of ITS genes and 18S rRNA gene sequencing of, respectively, that were associated with Bt and conventional cotton variety rhizosphere soils from different plant growth stages. qPCR analyses indicated that fungal abundances reached their peak at the seedling stage and that the taproots and lateral root rhizospheres of the Bt cotton SGK321 were significantly different. However, no significant differences in population sizes were detected between the same root zones from Bt and the conventional cotton varieties. The overall patterns of fungal genera abundances followed that of the dominant genera, whereas overall patterns of fungal genera richness followed those of the rare genera. These results suggest that the dominant and rare taxa play different roles in the maintenance of rhizosphere microhabitat ecosystems. Cluster analyses indicated a separation of fungal communities based on the lateral roots or taproots from the three cotton varieties at the seedling stage, suggesting that root microhabitats had marked effects on fungal community composition. Redundancy analyses indicated that pH was more correlated to soil fungal community composition than Bt protein content. CONCLUSIONS: In conclusion, these results indicate that dominant and rare fungal taxa differentially contribute to community dynamics in different root microhabitats of both Bt and conventional cotton varieties. Moreover, these results showed that the rhizosphere fungal community of Bt cotton did not respond significantly to the presence of Bt protein when compared to the two conventional cotton varieties.
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Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Endotoxinas/genética , Endotoxinas/metabolismo , Hongos/clasificación , Gossypium/microbiología , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Micobioma/genética , Raíces de Plantas/microbiología , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , ADN Intergénico/genética , Hongos/genética , Hongos/aislamiento & purificación , Gossypium/clasificación , ARN Ribosómico 18S/genética , Rizosfera , Microbiología del SueloRESUMEN
Pyrodextrin shares some properties of resistant starch, which is metabolically beneficial, and has potential applications as a functional food. In this study, we report that the oral administration of pyrodextrin (50 mg/kg/d for 7 weeks) decreased blood glucose (from 9.18 ± 1.47 to 7.67 ± 0.42 mmol/L), serum HbA1c, triglycerides, adipocyte size, and body weight (from 24.4 ± 1.2 to 22.5 ± 1.2 g) in mice with high-fat-diet-induced obesity. Western-blotting analysis suggested that pyrodextrins decreased intestinal SGLT-1 and GLUT-2 expression to â¼70 and â¼60% of the obese control, respectively, which slowed down glucose transportation from the gut into the blood and tentatively improved hepatic metabolism. Moreover, the pyrodextrin with a lower molecular weight of 44 kDa, a more branched structure, and increased nondigestible starch of 46.2 ± 0.3% showed stronger hypoglycemic activity. This work provides important information for developing pyrodextrins as a functional food and dietary supplement for the management of obesity and diabetes.