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1.
Phys Chem Chem Phys ; 26(19): 14186-14193, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38713092

RESUMEN

Cost-effective and readily accessible 3d transition metals (TMs) have been considered as promising candidates for alkane activation while 3d TMs especially the early TMs are usually not very reactive with light alkanes. In this study, the reactivity of Vn+ and VnO+ (n = 1-9) cluster cations towards ethane under thermal collision conditions has been investigated using mass spectrometry and density functional theory calculations. Among Vn+ (n = 1-9) clusters, only V3-5+ can react with C2H6 to generate dehydrogenation products and the reaction rate constants are below 10-13 cm3 molecule-1 s-1. In contrast, the reaction rate constants for all VnO+ (n = 1-9) with C2H6 significantly increase by about 2-4 orders of magnitude. Theoretical analysis evidences that the addition of ligand O affects the charge distribution of the metal centers, resulting in a significant increase in the cluster reactivity. The analysis of frontier orbitals indicates that the agostic interaction determines the size-dependent reactivity of VnO+ cluster cations. This study provides a novel approach for improving the reactivity of early 3d TMs.

2.
Chin J Traumatol ; 27(3): 163-167, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38216434

RESUMEN

PURPOSE: To study the clinical effectiveness of the topical application of tranexamic acid in hand tendon release. METHODS: This was a randomized controlled trial conducted after receiving approval from the local ethics committee according to guidelines from the Helsinki Declaration. Eighty patients who underwent hand tendon release operation in our hospital from January 2021 to December 2022 were included and randomly divided into 2 groups. Patients in the tranexamic acid group (40 cases) received intraoperative topical application of 2 g of tranexamic acid after tendon release, while patients in the conventional group (40 cases) did not receive topical application of tranexamic acid during operation. The operation time, perioperative hemoglobin changes, total blood loss, incidence of early postoperative complications, and total active movement (TAM) before surgery and 6 months after surgery were compared between the 2 groups. The continuous variable which follows normal distribution expressed by mean ± SD and used t-test to compare between groups. Meanwhile, categorical variables were used by Chi-square test, and a p < 0.05 indicated that the differences were statistically significant. RESULTS: Both groups were followed up for 7 - 18 months, with a mean of 10.3 months. Postoperative decrease in hemoglobin was significantly less in the tranexamic acid group than in the conventional group (t = 7.611, p < 0.001). The total blood loss in the tranexamic acid group (74.33 ± 20.50) mL was less than that in the conventional group (83.05 ± 17.73) mL, and the difference was statistically significant (p < 0.05). Both groups showed improvement in thumb/finger flexion and extension range of motion after surgery, and the TAM improved compared with those before surgery, and the difference was statistically significant (p < 0.001). The TAM improved more significantly in the tranexamic acid group (87.68° ± 10.44°) than in the conventional group (80.47° ± 10.93°) at 6 months after surgery, with a statistically significant difference (t = 3.013, p < 0.001). There was no significant difference in operation time and incidence of early postoperative complications between the 2 groups (p = 0.798, 0.499, respectively). CONCLUSION: The topical application of tranexamic acid during hand tendon release can significantly reduce postoperative bleeding and improve surgical efficacy, which is worth promoting.


Asunto(s)
Administración Tópica , Antifibrinolíticos , Ácido Tranexámico , Humanos , Ácido Tranexámico/administración & dosificación , Masculino , Femenino , Adulto , Antifibrinolíticos/administración & dosificación , Persona de Mediana Edad , Pérdida de Sangre Quirúrgica/prevención & control , Resultado del Tratamiento , Traumatismos de los Tendones/cirugía , Mano/cirugía , Tempo Operativo , Complicaciones Posoperatorias/prevención & control
3.
Undersea Hyperb Med ; 48(4): 417-423, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34847305

RESUMEN

This study aimed to compare the efficacy of two commonly used therapeutic pressures, 2.0 atmospheres absolute (ATA) versus 2.2 ATA, applied in hyperbaric oxygen (HBO2) therapy for sudden sensorineural hearing loss (SSNHL). We retrospectively reviewed the clinical records of 160 SSNHL patients treated by typical therapy or additional HBO2 therapy with pressure 2.0 or 2.2 ATA at Yijishan Hospital, the First Affiliated Hospital of Wannan Medical College, from February 2018 to May 2020. The pure-tone threshold audiometry results pre- and post-treatment were compared across three groups. In the range of frequencies 250-500 Hz, P2.0 (20.92±26.11 dB, p=0.047) and P2.2 group (20.47±±21.54 dB, p=0.012) both acquired higher hearing gain compared to the control group (11.94±23.32 dB). While in the range of frequencies 1,000-2,000 Hz, only the P2.2 group showed significant improvement of the hearing gain compared to the control group (19.70±21.13 dB vs.10.56±25.24 dB, p=0.015). In the range of frequencies 4,000-8,000, both the P2.0 and P2.2 groups failed to reach the desired effect. Our results suggest that the therapeutic effect is associated with HBO2 therapeutic pressure when applying HBO2 treatment combined with standard medical therapy. Within the range of appropriate pressure, the higher pressure, which means higher partial pressure of oxygen, has better therapeutic efficacy for SSNHL.


Asunto(s)
Pérdida Auditiva Sensorineural , Pérdida Auditiva Súbita , Audiometría de Tonos Puros , Pérdida Auditiva Sensorineural/terapia , Pérdida Auditiva Súbita/terapia , Humanos , Oxígeno , Estudios Retrospectivos , Resultado del Tratamiento
4.
Gut ; 65(1): 9-18, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25986943

RESUMEN

OBJECTIVE: To clarify the full range of benefits and adverse consequences of Helicobacter pylori eradication as a strategy for gastric cancer prevention, the community-based intervention trial was launched in Linqu County, China. DESIGN: A total of 184,786 residents aged 25-54 years were enrolled in this trial and received (13)C-urea breath test. H. pylori positive participants were assigned into two groups, either receiving a 10-day quadruple anti-H. pylori treatment or lookalike placebos together with a single dosage of omeprazole and bismuth. RESULTS: The prevalence of H. pylori in trial participants was 57.6%. A total of 94,101 subjects completed the treatment. The overall H. pylori eradication rate was 72.9% in the active group. Gender, body mass index, history of stomach disease, baseline delta over baseline-value of (13)C-urea breath test, missed medication doses, smoking and drinking were independent predictors of eradication failure. The missed doses and high baseline delta over baseline-value were important contributors in men and women (all Ptrend<0.001). However, a dose-response relationship between failure rate and smoking or drinking index was found in men (all Ptrend<0.001), while high body mass index (Ptrend<0.001) and history of stomach disease were significant predictors in women. The treatment failure rate increased up to 48.8% (OR 2.87, 95% CI 2.24 to 3.68) in men and 39.4% (OR 2.67, 95% CI 1.61 to 4.42) in women with multiple factors combined. CONCLUSIONS: This large community-based intervention trial to eradicate H. pylori is feasible and acceptable. The findings of this trial lead to a distinct evaluation of factors influencing eradication that should be generally considered for future eradication therapies. TRIAL REGISTRATION NUMBER: ChiCTR-TRC-10000979 in accordance with WHO ICTRP requirements.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Neoplasias Gástricas/prevención & control , Adulto , Antiulcerosos/uso terapéutico , China , Método Doble Ciego , Quimioterapia Combinada , Femenino , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/diagnóstico , Humanos , Masculino , Metronidazol/uso terapéutico , Persona de Mediana Edad , Estudios Prospectivos , Neoplasias Gástricas/microbiología , Tetraciclina/uso terapéutico , Resultado del Tratamiento
5.
Tumour Biol ; 37(1): 1211-5, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26282005

RESUMEN

RNA-sequencing technology is progressing day by day. Numerous researches have showed that long noncoding RNAs (lncRNAs) play oncogenic or tumor suppressor roles in tumor biological processes. To our knowledge, many studies have identified a lot of lncRNAs with aberrant expression in several types of cancers. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a newly discovered lncRNA, has been reported that is overexpressed in several types of cancers. But the clinical value of MALAT1 in cancers remains unclear. Therefore, in this present study, we aimed to investigate potential clinical application role of MALAT1 as a prognostic biomarker in malignant tumors. We performed a detailed search in PubMed, Embase, Medline, and Cochrane Library until July 2015. According to the inclusion and exclusion criteria, nine studies with a total of 941 patients were selected to explore the relationship between high expression of MALAT1 and overall survival in cancers. The result showed that overexpression of MALAT1 could predict poor overall survival (OS) in cancer patients, with pooled hazard ratio (HR) of 1.90 [95 % confidence interval (CI) 1.68-2.16, P < 0.0001]. In conclusion, the present meta-analysis demonstrated that high expression of MALAT1 might be served as a novel prognostic biomarker in different types of cancers.


Asunto(s)
Carcinoma/metabolismo , Regulación Neoplásica de la Expresión Génica , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Biomarcadores de Tumor/metabolismo , Carcinogénesis/genética , Carcinoma/diagnóstico , Humanos , Pronóstico , Modelos de Riesgos Proporcionales , Resultado del Tratamiento
6.
J Muscle Res Cell Motil ; 37(3): 95-100, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27460929

RESUMEN

The failure to accept reinnervation is considered to be one of the reasons for the poor motor functional recovery of intrinsic hand muscles (IHMs) after nerve injury. Rat could be a suitable model to be used in simulating motor function recovery of the IHMs after nerve injury as to the similarities in function and anatomy of the muscles between human and rat. However, few studies have reported the muscle fiber types composition and endplate morphologic characteristics of intrinsic forepaw muscles (IFMs) in the rat. In this study, the myosin heavy chain isoforms and acetylcholine receptors were stained by immunofluorescence to show the muscle fiber types composition and endplates on type-identified fibers of the lumbrical muscles (LMs), interosseus muscles (IMs), abductor digiti minimi (AM) and flexor pollicis brevis (FM) in rat forepaw. The majority of IFMs fibers were labeled positively for fast-switch fiber. However, the IMs were composed of only slow-switch fiber. With the exception of the IMs, the other IFMs had a part of hybrid fibers. Two-dimensional morphological characteristics of endplates on I and IIa muscle fiber had no significant differences among the IFMs. The LMs is the most suitable IFMs of rat to stimulate reinnervation of the IHMs after nerve injury. Gaining greater insight into the muscle fiber types composition and endplate morphology in the IFMs of rat may help understand the pathological and functional changes of IFMs in rat model stimulating reinnervation of IHMs after peripheral nerve injury.


Asunto(s)
Placa Motora/fisiología , Fibras Musculares Esqueléticas/fisiología , Animales , Pie/fisiología , Miembro Anterior/fisiología , Ratas
7.
J Hand Surg Am ; 40(7): 1382-8, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25953529

RESUMEN

PURPOSE: To report our experience with the use of a digital artery perforator propeller flap based on a constant distal perforator in the middle phalanx for resurfacing of lateral oblique fingertip amputations. METHODS: Twelve fingertips in 10 patients underwent reconstruction, with a mean follow-up of 8 months (range, 8-12 mo). The size of the flaps ranged from 2.5 × 1.5 cm to 3.0 × 2.0 cm. RESULTS: All flaps survived entirely and restored a rounded fingertip contour. Mean static 2-point discrimination was 5 mm (range, 4-6 mm). With the exception of 1 patient with an amputation at the distal interphalangeal joint, the distal interphalangeal joint was preserved in all patients and had 30° to 60° of motion at final follow-up. No patients complained of cold intolerance or residual joint contracture. No hooked nail deformity occurred in patients who had remaining nailbed. CONCLUSIONS: The digital artery perforator propeller flap is particularly suited to coverage of a lateral oblique fingertip defect, because only a 90° rotation is required when inset, and the bulk of the flap serves to restore the rounded contour of the fingertip. The skin over the entire dorsal surface of the middle phalanx can be elevated as a flap, providing adequate tissue to resurface the defect and restore a rounded contour to the fingertip. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Asunto(s)
Traumatismos de los Dedos/cirugía , Colgajo Perforante/irrigación sanguínea , Colgajo Perforante/inervación , Procedimientos de Cirugía Plástica/métodos , Adulto , Amputación Traumática , Femenino , Humanos , Masculino , Persona de Mediana Edad
8.
Tumour Biol ; 35(9): 8939-43, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24899264

RESUMEN

C-erbB2 (HER-2/neu) plays an important role in the progression of several types of cancer by increasing tumor growth, migration, invasion, and metastasis and is associated with poor disease prognosis. Numerous studies examining the relationship between c-erbB2 expression and prognostic impact in patients with osteosarcoma have yielded inconclusive results. We therefore conducted a meta-analysis to provide a comprehensive evaluation of the prognostic role of c-erbB2 expression on 5-year survival, which compared the positive and negative expression of c-erbB2 in patients of the available studies. A detailed search was made in PubMed for relevant original articles published in English. Finally, a total of eight studies with 411 osteosarcoma patients were involved to estimate the relationship between c-erbB2 expression and 5-year overall survival. Positive expressions of c-erbB2 predicted poorer survival in osteosarcoma with the pooled RR of 1.53 (95 % CI 1.20-1.94, P = 0.0006). In conclusion, the findings from this present meta-analysis suggest that c-erbB2 overexpression is related to poor prognostic of osteosarcoma and can be a useful clinical prognostic factor for those patients.


Asunto(s)
Neoplasias Óseas/metabolismo , Osteosarcoma/metabolismo , Receptor ErbB-2/biosíntesis , Neoplasias Óseas/patología , Humanos , Inmunohistoquímica , Osteosarcoma/patología , Pronóstico , Análisis de Supervivencia
9.
Parasitol Res ; 113(2): 607-12, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24276645

RESUMEN

Stem cell therapy is an interventional treatment that introduces new cells into damaged tissues, which help in treating many diseases and injuries. It has been proved that stem cell therapy is effective for the treatment of cancers, diabetes mellitus, Parkinson's disease, Huntington's disease, cardiovascular diseases, neurological disorders, and many other diseases. Recently, stem cell therapy has been introduced to treat parasitic infections. The culture supernatant of mesenchymal stem cells (MSCs) is found to inhibit activation and proliferation of macrophages induced by the soluble egg antigen of Schistosoma japonicum, and MSC treatment relieves S. japonicum-induced liver injury and fibrosis in mouse models. In addition, transplantation of MSCs into naïve mice is able to confer host resistance against malaria, and MSCs are reported to play an important role in host protective immune responses against malaria by modulating regulatory T cells. In mouse models of Chagas disease, bone marrow mononuclear cell has been shown effective in reducing inflammation and fibrosis in mice infected with Trypanosoma cruzi, and transplantation of the bone marrow mononuclear cells prevents and reverses the right ventricular dilatation induced by T. cruzi infection in mice. Preliminary clinical trials demonstrate that transplantation of bone marrow derived-cells may become an important therapeutic modality in the management of end-stage heart diseases associated with Chagas disease. Based on these exciting results, it is considered by stating that it is firmly believed that, within the next few years, we will be able to find the best animal models and the appropriate stem cell type, stem cell number, injection route, and disease state that will result in possible benefits for the patients with parasitic infections, and stem cell therapy, although at an initial stage currently, will become a real therapeutic option for parasitic diseases.


Asunto(s)
Trasplante de Médula Ósea , Enfermedad de Chagas/terapia , Malaria/terapia , Trasplante de Células Madre Mesenquimatosas , Enfermedades Parasitarias/terapia , Esquistosomiasis Japónica/terapia , Animales , Cardiomiopatía Chagásica/terapia , Modelos Animales de Enfermedad , Humanos , Malaria/inmunología , Células Madre Mesenquimatosas/fisiología , Ratones , Linfocitos T Reguladores/inmunología
10.
Undersea Hyperb Med ; 41(2): 135-41, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24851551

RESUMEN

BACKGROUND: Pseudomonas aeruginosa (P. aeruginosa) is a common microbe isolated from divers with ear and skin infections. To obtain the epidemic characters of the occurrence of the P. aeruginosa infection, multilocus sequence typing (MLST) was used to assess the genetic background of different strains isolated from divers involved in saturation diving. METHODS: A total of 64 P. aeruginosa strains from naval divers were sequenced by multilocus sequence typing using seven housekeeping genes (acsA, aroE, guaA, mutL, nuoD, ppsA and trpE). The results were analyzed based on the P. aeruginosa international MLST database to obtain the allelic profiles and sequence types (STs). MLST data were analyzed by Bionumerics 4.0 (http: // pubmlst.org/mlstanalyse) using LIAN and eBURST. Twenty-eight strains with the typical genotype were selected for further analysis of pathogenic characteristics by Caenorhabditis elegans (C. elegans) fast killing model. RESULTS: Data from MLST revealed a high STs diversity among the strains. Of the 64 strains, 53 strains were assigned to 19 STs, and the remaining 11 clones could not be assigned. ST274 accounted for 18.5% (12/64), and ST260 accounted for 15.62% (10/64). C. elegans killing assay showed that all the test strains had distinct virulent properties as compared with the negative control group. Clone 503-1 had the highest virulence and clone 54 had the lowest virulence as compared with the positive clinical group. CONCLUSION: The P. aeruginosa strains carried by the occupational diver groups in Chinese regions have characteristically dominant STs, and have a relatively strong virulence as compared with the standard strain and the clinically isolated positive control strain.


Asunto(s)
Técnicas de Tipificación Bacteriana , Buceo , Tipificación de Secuencias Multilocus , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/patogenicidad , Adulto , Alelos , Animales , Caenorhabditis elegans , Cartilla de ADN/genética , Oído Externo/microbiología , Genotipo , Helio , Humanos , Personal Militar , Oxígeno , Pseudomonas aeruginosa/aislamiento & purificación , Enfermedades Cutáneas Bacterianas/microbiología , Especificidad de la Especie , Virulencia/genética , Adulto Joven
11.
IEEE Trans Image Process ; 33: 2572-2586, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38470580

RESUMEN

Recently, visual food analysis has received more and more attention in the computer vision community due to its wide application scenarios, e.g., diet nutrition management, smart restaurant, and personalized diet recommendation. Considering that food images are unstructured images with complex and unfixed visual patterns, mining food-related semantic-aware regions is crucial. Furthermore, the ingredients contained in food images are semantically related to each other due to the cooking habits and have significant semantic relationships with food categories under the hierarchical food classification ontology. Therefore, modeling the long-range semantic relationships between ingredients and the categories-ingredients semantic interactions is beneficial for ingredient recognition and food analysis. Taking these factors into consideration, we propose a multi-task learning framework for food category and ingredient recognition. This framework mainly consists of a food-orient Transformer named Convolution-Enhanced Bi-Branch Adaptive Transformer (CBiAFormer) and a multi-task category-ingredient recognition network called Structural Learning and Cross-Task Interaction (SLCI). In order to capture the complex and unfixed fine-grained patterns of food images, we propose a query-aware data-adaptive attention mechanism called Bi-Branch Adaptive Attention (BiA-Attention) in CBiAFormer, which consists of a local fine-grained branch and a global coarse-grained branch to mine local and global semantic-aware regions for different input images through an adaptive candidate key/value sets assignment for each query. Additionally, a convolutional patch embedding module is proposed to extract the fine-grained features which are neglected by Transformers. To fully utilize the ingredient information, we propose SLCI, which consists of cross-layer attention to model the semantic relationships between ingredients and two cross-task interaction modules to mine the semantic interactions between categories and ingredients. Extensive experiments show that our method achieves competitive performance on three mainstream food datasets (ETH Food-101, Vireo Food-172, and ISIA Food-200). Visualization analyses of CBiAFormer and SLCI on two tasks prove the effectiveness of our method. Codes will be released upon publication. Code and models are available at https://github.com/Liuyuxinict/CBiAFormer.


Asunto(s)
Culinaria , Aprendizaje
12.
IEEE Trans Pattern Anal Mach Intell ; 46(9): 6280-6291, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38507388

RESUMEN

Data-free knowledge distillation (DFKD) improves the student model (S) by mimicking the class probability from a pre-trained teacher model (T) without training data. Under such setting, an ideal scenario is that T can help generate "good" samples from a generator (G) to maximally benefit S. However, existing arts suffer from the non-ideal generated samples under the disturbance of the gap (i.e., either too large or small) between the class probabilities of T and S; for example, the generated samples with too large gap may exhibit excessive information for S, while too small gap leads to the limited knowledge in the samples, resulting into the poor generalization. Meanwhile, they fail to judge the "goodness" of the generated samples for S since the fixed T is not necessarily ideal. In this paper, we aim to answer what is inside the gap box; together with how to yield "good" generated samples for DFKD? To this end, we propose a Gap-Sensitive Sample Generation (GapSSG) approach, by revisiting the empirical distilled risk from a data-free perspective, which confirms the existence of an ideal teacher (T *), while theoretically implying: (1) the gap disturbance originates from the mismatch between T and T *, hence the class probabilities of T enable the approximation to those of T *; and (2) "good" samples should maximally benefit S via T's class probabilities, owing to unknown T *. To this end, we unpack the gap box between T and S as two findings: inherent gap to perceive T and T *; derived gap to monitor S and T *. Benefiting from the derived gap that focuses on the adaptability of generated sample to S, we attempt to track student's training route (a series of training epochs) to capture the category distribution of S; upon which, a regulatory factor is further devised to approximate T * over inherent gap, so as to generate "good" samples to S. Furthermore, during the distillation process, a sample-balanced strategy comes up to tackle the overfitting and missing knowledge issues between the generated partial and critical samples by training G. The theoretical and empirical studies verify the advantages of GapSSG over the state-of-the-arts.

13.
J Hazard Mater ; 470: 134193, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38569341

RESUMEN

Arsenopyrite and pyrite often coexist in metal deposits and tailings, thus simultaneous bioleaching of both sulfides has economic (as well as environmental) significance. Important targets in bio-oxidation operations are high solubilization rates and minimized accumulation of Fe(III)/As-bearing secondary products. This study investigated the role of pyrite bioleaching in the enhancement of arsenopyrite dissolution. At a pyrite to arsenopyrite mass ratio of 1:1, 93.6% of As and 93.0% of Fe were solubilized. The results show that pyrite bio-oxidation can promote arsenopyrite dissolution, enhance S0 bio-oxidation, and inhibit the formation of jarosites, tooeleite, and amorphous ferric arsenate. The dry weight of the pyrite & arsenopyrite residue was reduced by 95.1% after bioleaching, compared to the initial load, while only 5% weight loss was observed when pyrite was absent. A biofilm was formed on the arsenopyrite surface in the presence of pyrite, while a dense passivation layer was observed in the absence of pyrite. As(III) (as As2O3) was a dominant As species in the pyrite & arsenopyrite residue. Novel and detailed findings are presented on arsenopyrite bio-dissolution in the presence of pyrite, and the presented approach could contribute to the development of novel cost-effective extractive bioprocesses. ENVIRONMENTAL IMPLICATION: The oxidation of arsenopyrite presents significant environmental hazards, as it can contribute to acid mine drainage generation and arsenic mobilization from sulfidic mine wastes. Bioleaching is a proven cost-effective and environmentally friendly extractive technology, which has been applied for decades in metal recovery from minerals or tailings. In this work, efficient extraction of arsenic from arsenopyrite bioleaching was presented through coupling the process with bio-oxidation of pyrite, resulting in lowered accumulation of hazardous and metastable Fe(III)/As-bearing secondary phases. The results could help improve current biomining operations and/or contribute to the development of novel cost-effective bioprocesses for metal extraction.


Asunto(s)
Arsenicales , Compuestos de Hierro , Hierro , Minerales , Sulfuros , Sulfuros/química , Hierro/química , Arsenicales/química , Cinética , Minerales/química , Compuestos de Hierro/química , Oxidación-Reducción , Solubilidad , Arsénico/química , Biopelículas , Acidithiobacillus/metabolismo
14.
Mol Biol Rep ; 40(4): 3409-18, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23266670

RESUMEN

The interaction between ovalbumin (OVA) and three purine alkaloids (caffeine, theophylline and diprophylline) was investigated by the aid of intrinsic and synchronous fluorescence, ultraviolet-vis absorbance, resonance light-scattering spectra and three-dimensional fluorescence spectra techniques. Results showed that the formation of complexes gave rise to the fluorescence quenching of OVA by caffeine, theophylline, and diprophylline. Static quenching was confirmed to results in the fluorescence quenching. The binding site number n, apparent binding constant KA and corresponding thermodynamic parameters were measured at different temperatures. The binding process was spontaneous molecular interaction procedures in which both enthalpy and Gibbs free energy decreased. Van der Waals forces and hydrogen bond played a major role in stabilizing the complex. The comparison between caffeine, theophylline, and diprophylline was made, and thermodynamic results showed that diprophylline was the strongest quencher and bound to OVA with the highest affinity among three compounds. The influence of molecular structure on the binding aspects was reported.


Asunto(s)
Cafeína/química , Difilina/química , Ovalbúmina/química , Teofilina/química , Sitios de Unión , Fluorescencia , Enlace de Hidrógeno , Estructura Molecular , Unión Proteica , Espectrometría de Fluorescencia , Termodinámica
15.
Curr Microbiol ; 67(3): 379-87, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23657849

RESUMEN

The effect of glucose and elemental sulfur on the growth and PHB accumulation of Acidiphilium cryptum DX1-1 was investigated. Meanwhile, the differential expressions of 19 genes related with PHB accumulation, sulfur metabolism and carbon fixed in heterotrophy, phytotrophy and mixotrophy were studied by RT-qPCR. The results showed that strain DX1-1 could accumulate PHB with sulfur as the energy substance and atmospheric CO2 as carbon resource. Glucose could improve the growth of strain DX1-1 cultured in medium with sulfur as the energy substance, and almost all the key enzyme-encoding genes related with PHB, sulfur metabolism and carbon fixed were basically up-regulated. PHB polymerase (Arcy_3030), ribulose-bisphosphate carboxylase (Acry_0825), ribulose-phosphate-epimerase (Acry_0022), and cysteine synthase A (Acry_2560) played important role in PHB accumulation, the modified expression of which could influence the PHB yield. With CO2 as carbon resource, the main initial substance of PHB accumulation for strain DX1-1 was acetyl-CoA, instead of acetate with the glucose as the carbon resource. Because of accumulating PHB by fixed atmospheric CO2 while independent of light, A. cryptum DX1-1 may have specifically potential in production of PHB.


Asunto(s)
Acidiphilium/metabolismo , Glucosa/metabolismo , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Azufre/metabolismo , Acidiphilium/genética , Dióxido de Carbono/metabolismo , Metabolismo Energético , Perfilación de la Expresión Génica , Redes y Vías Metabólicas/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
16.
Head Face Med ; 19(1): 14, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37038160

RESUMEN

OBJECTIVE: This study aimed to study the cytokines in gingival crevicular fluid (GCF) of the teeth opposing to dental implants and 3-unit fixed partial dentures (FPDs). MATERIALS AND METHODS: A total of 74 participants were recruited for this cross-sectional study. Based on the status of lower first molars, the participants were divided into dental implants group and 3-unit FPDs group. Social index and oral hygiene were recorded. Occlusal loading was evaluated with a T-scan. GCF was sampled from the upper first molar and assessed with a commercial cytokine assay kit. RESULTS: Forty three dental implants patients and 31 3-unit FPDs patients received all of the clinical and laboratory evaluation. The dental implants group had a higher occlusion force distribution on first molars region. IL-10, IL-17, RANK had a higher mean in dental implants group and was associated with occlusion force of first molar. There was a weakly association between IL-10 and dental implants in the binary logistic regression analyses. CONCLUSIONS: In this study, the teeth opposing implants have a higher level of cytokines in the GCF than teeth opposing to 3-unit FPDs in periodontal healthy participants because of the poor osseoperception of dental implants. IL-10 might reflect a higher occlusion force in dental implants region. CLINICAL RELEVANCE: This study provided that different tooth restoration methods could influence the periodontal status of the contact teeth.


Asunto(s)
Citocinas , Implantes Dentales , Humanos , Citocinas/análisis , Interleucina-10/análisis , Líquido del Surco Gingival/química , Estudios Transversales , Dentadura Parcial Fija
17.
Zhongguo Gu Shang ; 36(12): 1165-8, 2023 Dec 25.
Artículo en Zh | MEDLINE | ID: mdl-38130226

RESUMEN

OBJECTIVE: To measure and compare medial proximal tibial angle (MPTA) of lower limbs under different axial rotation angles(neutral position, 30° internal rotation, 30° external rotation) on the load position radiographs, and explore changes and significance of MPTA measured within and between groups of tibia at different axial rotation positions. METHODS: From January 2018 to December 2018, 40 patients with knee osteoarthritis (KOA) were selected, with a total of 80 limbs, including 12 males and 28 females, aged from 29 to 73 years old with an average of (59.6±12.7) years old. Full length radiographs of the lower limbs were taken on neutral tibia position, 30° internal rotation and 30° external rotation, respectively. MPTA was measured and the results were compared between groups and within groups. RESULTS: MPTA measured on the left lower extremity of neutral tibia, 30° internal rotation and 30° external rotation were (86.08±2.48) °, (88.62±2.94) ° and (83.47±3.10) °, respectively. MPTA measured on the right lower limb were (86.87±1.97) °, (89.02±2.39) ° and (83.80±2.77) °, respectively, and there were no significant difference in MPTA measured between rotation angle group (P>0.05). While there were statistical difference in MPTA on the same limb between groups (P<0.05). On 30° internal rotation, MPTA of left and right lower limbs increased by (2.54±1.74) ° and (2.15±1.78) ° compared with tibia neutral position. On 30° external rotation, MPTA of left and right lower limbs decreased (2.61±2.03) ° and (3.07±1.75) ° compared with tibial neutral position. CONCLUSION: When a full-length X-ray film is taken on the weight-bearing position of both lower limbs, if there is axial rotation or external rotation of tibia, MPTA will increase or decrease compared with neutral position, which may cause a certain degree of deviation in clinical operation based on the accurate measurement of MPTA. However, the extent to which this bias affects the clinical operation effect remains to be verified. In addition, limited by the total number of samples and the number of measurement groups, whether there is a linear relationship between MPTA deviation and tibial axial rotation needs to be further studied.


Asunto(s)
Osteoartritis de la Rodilla , Tibia , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Tibia/diagnóstico por imagen , Tibia/cirugía , Extremidad Inferior , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/cirugía , Radiografía , Osteotomía/métodos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Estudios Retrospectivos
18.
Sci Rep ; 13(1): 11659, 2023 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-37468556

RESUMEN

In some complicated situations, decompression sickness (DCS) combined with other injuries, such as irradiation, will seriously endanger life safety. However, it is still unclear whether irradiation will increase the incidence of DCS. This study was designed to investigate the damage effects of irradiation on decompression injury and the underlying mechanism. Sprague-Dawley rats were exposed to irradiation followed by hyperbaric decompressing and the mortality and decompression symptoms were observed. Lung tissue and bronchoalveolar lavage fluid were collected to detect the lung lesion, inflammation response, activity of the angiotensin system, oxidative stress, and relative signal pathway by multiple methods, including Q-PCR, western blot, and ELISA. As a result, pre-exposure to radiation significantly exacerbated disease outcomes and lung lesions of DCS. Mechanically, the up-regulation of angiotensin-converting enzyme expression and angiotensin II levels was responsible for the exacerbated DCS and lung lesions caused by predisposing irradiation exposure. Oxidative stress and PI3K/AKT signal pathway activation in pulmonary tissue were enhanced after irradiation plus decompression treatment. In conclusion, our results suggested that irradiation could exacerbate lung injury and the outcomes of DCS by activating the angiotensin system, which included eliciting oxidative stress and activation of the PI3K/AKT signal pathway.


Asunto(s)
Enfermedad de Descompresión , Ratas , Animales , Ratas Sprague-Dawley , Enfermedad de Descompresión/etiología , Enfermedad de Descompresión/metabolismo , Angiotensina II , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt
19.
Can J Microbiol ; 58(2): 158-69, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22280841

RESUMEN

Pseudomonas aeruginosa is an important opportunistic pathogen associated with multiple diseases including cystic fibrosis and nosocomial infections. Pseudomonas aeruginosa is also the microbe most often isolated from ear and skin infections in divers. Saturation divers often suffer from various skin and mucous disorders, of which P. aeruginosa infections are the most serious and frequent. Previous studies mainly focused on adaptive and regulatory mechanisms of P. aeruginosa virulence in inducing clinical acute and chronic infections under different environmental conditions. However, there are few studies describing the physiological adaptive and regulatory mechanisms of P. aeruginosa in inducing high infectivity in healthy divers under hyperbaric oxyhelium conditions and even fewer studies describing the overall influence of the hyperbaric oxyhelium environment on regulating mRNA and protein expression levels of P. aeruginosa. The present study used transcriptomic and virulence phenotype analysis to identify factors that allow P. aeruginosa to become established in a hyperbaric oxyhelium environment to facilitate infections in divers. Transcriptional profiling of P. aeruginosa grown under steady-state hyperbaric oxyhelium stress conditions showed an upregulation of genes associated with stress-sense/response, protein folding, transcriptional regulation, pili and flagellum metabolism, virulence adaptation, and membrane protein metabolism. Some of these genes (including several two-component systems not previously known to be influenced by hyperbaric oxyhelium) were differentially expressed by P. aeruginosa in response to 72 h of exposure to hyperbaric oxyhelium stress. Detection of the virulence phenotype confirmed the results of cDNA microarrays. Based on these results, we conclude that hyperbaric oxyhelium conditions affect PAO1 gene expression and upregulate the expression of most virulence genes. The data obtained in our study may provide new insight into the molecular mechanism of hyperbaric oxyhelium exposure against P. aeruginosa virulence adaptation.


Asunto(s)
Pseudomonas aeruginosa/fisiología , Adaptación Fisiológica , Presión Atmosférica , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Flagelos/metabolismo , Análisis por Micromatrices , Análisis de Secuencia por Matrices de Oligonucleótidos , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/patogenicidad , Virulencia/genética , Factores de Virulencia/genética , Factores de Virulencia/metabolismo
20.
J Plast Surg Hand Surg ; 56(5): 310-317, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34581658

RESUMEN

We aimed to determine the surface locations of the nerve fascicles that innervate the lumbricals and interossei, re-examine the branching pattern of the deep branch of the ulnar nerve (dUN), and provide a clear description of their course. Eleven fresh-frozen adult cadaver hands were investigated. Nerve fascicles that innervate the lumbricals, interossei, and surface landmarks including the distal wrist crease and 2-5 proximal finger creases were marked by radio opaque fibers and subjected to X-ray. We analyzed the images and set a quadrant-linked hand surface. Subsequently, we measured the lengths of both axes and the coordinates of the branch locations in the quadrant. The surface locations of branches that innervated the lumbricals and interossei were clearly quantified. The branches of dUN exhibited a 4-group distribution pattern. Novel methods for quantitatively locating the surface anatomy of these branches and demonstration of a 4-group branching pattern of the dUN were established.


Asunto(s)
Mano , Nervio Cubital , Adulto , Cadáver , Humanos , Músculos , Nervio Cubital/diagnóstico por imagen , Muñeca
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