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1.
Nature ; 544(7650): 322-326, 2017 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-28346939

RESUMEN

Oxetanocin A (OXT-A) is a potent antitumour, antiviral and antibacterial compound. Biosynthesis of OXT-A has been linked to a plasmid-borne Bacillus megaterium gene cluster that contains four genes: oxsA, oxsB, oxrA and oxrB. Here we show that both the oxsA and oxsB genes are required for the production of OXT-A. Biochemical analysis of the encoded proteins, a cobalamin (Cbl)-dependent S-adenosylmethionine (AdoMet) radical enzyme, OxsB, and an HD-domain phosphohydrolase, OxsA, reveals that OXT-A is derived from a 2'-deoxyadenosine phosphate in an OxsB-catalysed ring contraction reaction initiated by hydrogen atom abstraction from C2'. Hence, OxsB represents the first biochemically characterized non-methylating Cbl-dependent AdoMet radical enzyme. X-ray analysis of OxsB reveals the fold of a Cbl-dependent AdoMet radical enzyme, a family of enzymes with an estimated 7,000 members. Overall, this work provides a framework for understanding the interplay of AdoMet and Cbl cofactors and expands the catalytic repertoire of Cbl-dependent AdoMet radical enzymes.


Asunto(s)
Adenina/análogos & derivados , Bacillus megaterium/enzimología , Proteínas Bacterianas/metabolismo , Biocatálisis , Coenzimas/metabolismo , S-Adenosilmetionina/metabolismo , Vitamina B 12/metabolismo , Adenina/biosíntesis , Adenosina Monofosfato/metabolismo , Bacillus megaterium/genética , Bacillus megaterium/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Cristalografía por Rayos X , Nucleótidos de Desoxiadenina/metabolismo , Genes Bacterianos/genética , Modelos Moleculares , Familia de Multigenes/genética , Conformación Proteica
2.
Zhonghua Wai Ke Za Zhi ; 61(9): 801-806, 2023 Sep 01.
Artículo en Zh | MEDLINE | ID: mdl-37491174

RESUMEN

Objective: To examine the feasibility of the modified gasless trans-subclavian approach endoscopic thyroidectomy for lateral neck dissection (LND) in papillary thyroid carcinoma (PTC). Methods: The clinical data of 31 patients with PTC who underwent modified gasless trans-subclavian approach endoscopic LND in the Department of Head and Neck Surgery, Run Run Shaw Hospital, from January to October 2022 were retrospectively analyzed. There were 2 males and 29 females, aged (32.6±8.3) years (range: 17 to 55 years). The maximum diameter of the primary thyroid lesion (M(IQR)) was 1.06 (1.16) cm (range: 0.53 to 2.44 cm), and the maximum diameter of the metastatic lymph node was (1.04±0.37) cm (range: 0.44 to 1.88 cm). Operation time, postoperative hospital stay, number of lymph nodes dissected, and postoperative complications were recorded. Outpatient follow-up was conducted until November 30, 2022. Results: All operations were successfully completed with the endoscopy approach without conversion to open surgery. The operation time was 160 (20) minutes (range: 100 to 215 minutes), and the postoperative hospital stay was 4 (2) days (range: 2 to 14 days). The number of lymph nodes obtained by dissection in the central and lateral compartment of the neck was 11 (12) (range: 0 to 37) and 34.7±14.8 (range: 15 to 69), respectively. Temporary hypoparathyroidism occurred in 4 cases and all recovered within 1 month after the operation. One case suffered from recurrent laryngeal nerve injury (continuing followed up to assess whether it is a temporary injury). The complication of LND included 1 case of chylous leakage that was recovered with conservative treatment, 1 case of Horner syndrome returned to normal 3 months after surgery. During follow-up, there was no residual tumor or recurrence. Conclusion: The modified gasless trans-subclavian approach endoscopic LND for PTC is feasible, with a thorough dissection and concealed incision.


Asunto(s)
Carcinoma Papilar , Neoplasias de la Tiroides , Masculino , Femenino , Humanos , Cáncer Papilar Tiroideo/cirugía , Disección del Cuello , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología , Estudios Retrospectivos , Carcinoma Papilar/cirugía , Endoscopía , Tiroidectomía
3.
J Microsc ; 286(1): 3-12, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34879153

RESUMEN

Superconducting windings will be necessary in future fusion reactors to generate the strong magnetic fields needed to confine the plasma, and these superconducting materials will inevitably be exposed to neutron damage. It is known that this exposure results in the creation of isolated damage cascades, but the presence of these defects alone is not sufficient to explain the degradation of macroscopic superconducting properties and a quantitative method is needed to assess the subtle lattice damage in between the clusters. We have studied REBCO-coated conductors irradiated with neutrons to a cumulative dose of 3.3 × 1022  n/m2  that show a degradation of both Tc  and Jc values, and use HRTEM analysis to show that this irradiation introduces ∼10 nm amorphous collision cascades. In addition, we introduce a new method for the analysis of these images to quantify the degree of lattice disorder in the apparently perfect matrix between these cascades. This method utilises Fast Fourier and Discrete Cosine Transformations of a statistically relevant number of HRTEM images of pristine, neutron-irradiated and amorphous samples and extracts the degree of randomness in terms of entropy values. Our results show that these entropy values in both mid-frequency band FFT and DCT domains correlate with the expected level of lattice damage, with the pristine samples having the lowest and the fully amorphous regions the highest entropy values.  Our methodology allows us to quantify 'invisible' lattice damage to and correlate these values to the degradation of superconducting properties, and also has relevance for a wider range of applications in the field of electron microscopy where small changes in lattice perfection need to be measured.

4.
Lett Appl Microbiol ; 74(4): 593-603, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35014712

RESUMEN

Lactic acid bacteria are micro-organisms used for probiotic purposes and form major parts of human and mammalian intestinal microbiota, exerting important health-promoting effects on the host. Here, we evaluated Lactobacillus reuteri strain S5 isolated from the intestines of healthy white feather broilers. Lactobacillus reuteri S5 grew best after 20 h of incubation in MRS medium. Lactic acid production was 1·42 mmol l-1 at 24 h, which was well tolerated. Activities of T-AOC, GSH-Px and T-SOD in the cell-free fermentation supernatant of L. reuteri S5 were higher than those in the bacteria, and the strain showed good hydrophobicity in vitro. The dominant carbon and nitrogen sources of L. reuteri S5 were glucose and soybean meal. A high-quality complete genome map of L. reuteri S5 was obtained using a Pacbio nanopore third-generation sequencing platform. The results showed that L. reuteri S5 possesses a complete primary metabolic pathway, encoding the main functional enzymes of the glycolysis pathway and pentose phosphate pathway. The genome contains genes encoding antioxidants and conferring tolerance to inorganic salt ions, acids and bile salts. This study shows that L. reuteri S5 is a probiotic strain with excellent probiotic characteristics and has great potential for the development of feed additives to promote animal health.


Asunto(s)
Lactobacillales , Limosilactobacillus reuteri , Probióticos , Animales , Pollos , Intestinos/microbiología , Limosilactobacillus reuteri/genética , Mamíferos , Probióticos/metabolismo
5.
Zhonghua Yi Xue Za Zhi ; 102(13): 954-960, 2022 Apr 05.
Artículo en Zh | MEDLINE | ID: mdl-35385968

RESUMEN

Objective: To investigate the feasibility of multi-slice spiral CT(MSCT) imaging features of gastric stromal tumor (GST) in predicting pathological NIH risk classification, providing imaging basis for patients with GST before treatment. Methods: The clinical and CT imaging data of 504 patients(506 GST lesions), 259males and 245 females, aged from 13 to 85(60±11) years, with GST confirmed by surgery and pathology collected in the Zhongshan Hospital Affiliated to Fudan University and the Affiliated TCM Hospital of Southwest Medical University. According to pathological NIH risk classification, 506 lesions were divided into low risk group (very low and low risk degree, 277 lesions) and high risk group (medium and high risk degree, 229 lesions).Clinical data and imaging characteristics were compared between two groups. Multivariate logistic regression analysis was performed to screen out independent risk factors for statistically significant imaging indicators. Receiver operating curve (ROC) was used to evaluate the predictive value of tumor length for risk classification. Resulst: Between low risk group and high risk group,there were significant differences in gender(male/female:131/146 vs 129/100), gastrointestinal bleeding(present/absent:39/238 vs 59/170), morphology(regular/Irregular:218/59 vs 95/134), calcification(present/absent:36/241 vs 53/176), degree of necrosis(0°/Ⅰ°/Ⅱ°/Ⅲ°:197/61/16/3 vs 58/98/32/41), ulceration(present/absent:32/245 vs 94/135), growth pattern(endophytic/exophytic/mixed:102/105/70 vs 44/98/87), tumor location(fundus/cardia/body/angle/antrum:98/7/135/12/25 vs 98/6/114/5/6), feeding artery(present/absent:32/245 vs 104/125), vascular enhancement(present/absent:19/258 vs 88/141), effusion of around the disease(present/absent:0/277 vs 13/216), positive sign of fat around the disease(present/absent:0/277 vs 30/199),maximum long diameter[2.82(2.04,3.80) cm vs 5.93(4.06,8.29) cm] and short diameter [2.31(1.60,2.88) cm vs 4.40(3.21,6.37) cm]of tumor(all P<0.05).The maximum long diameter of tumor (OR=2.08,95%CI:1.35-3.20) and ulceration positive(OR=2.01,95%CI:1.03-3.92) were independent risk factors of risk classification(all P<0.05).Gastric antrum was used as the reference for tumor location, gastric fundus(OR=7.77,95%CI:2.00-30.24) and gastric body(OR=3.93,95%CI:1.03-15.01) were independent risk factors of risk classification(all P<0.05).The area under curve(AUC) of the maximum long diameter of tumor for predicting risk classification was 0.87, and the optimal critical value, sensitivity and specificity were 4.98cm, 62.9% and 95.3% respectively. Conclusions: MSCT image features of GST had certain characteristics. MSCT has certain predictive value for pathological NIH risk classification of GST, which can provide certain imaging basis for patients before treatment.


Asunto(s)
Tumores del Estroma Gastrointestinal , Neoplasias Gástricas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cardias/patología , Estudios de Factibilidad , Femenino , Tumores del Estroma Gastrointestinal/diagnóstico por imagen , Tumores del Estroma Gastrointestinal/patología , Humanos , Masculino , Persona de Mediana Edad , National Institutes of Health (U.S.) , Estudios Retrospectivos , Neoplasias Gástricas/cirugía , Tomografía Computarizada Espiral , Estados Unidos , Adulto Joven
6.
Zhonghua Fu Chan Ke Za Zhi ; 57(11): 836-842, 2022 Nov 25.
Artículo en Zh | MEDLINE | ID: mdl-36456480

RESUMEN

Objective: To compare oxytocin combined with ergometrine with oxytocin alone in terms of primary prophylaxis for postpartum hemorrhage (PPH) at the time of cesarean section (CS). Methods: This was a multicenter double-blind randomized controlled interventional study comparing ergometrine combined with oxytocin and oxytocin alone administered at CS. From December 2018 to November 2019, a total of 298 parturients were enrolled in 16 hospitals nationwide. They were randomly divided into experimental group (ergometrine intra-myometrial injection following oxytocin intravenously; 148 cases) and control group (oxytocin intra-myometrial injection following oxytocin intravenously; 150 cases) according to 1∶1 random allocation. The following indexes were compared between the two groups: (1) main index: blood loss 2 hours (h) after delivery; (2) secondary indicators: postpartum blood loss at 6 h and 24 h, placental retention time, incidence of PPH, the proportion of additional use of uterine contraction drugs, hemostatic drugs or other hemostatic measures at 2 h and 24 h after delivery, the proportion requiring blood transfusion, and the proportion of prolonged hospital stay due to poor uterine involution; (3) safety indicators: nausea, vomiting, dizziness and other adverse reactions, and blood pressure at each time point of administration. Results: (1) The blood loss at 2 h after delivery in the experimental group [(402±18) ml] was less than that in the control group [(505±18) ml], and the difference was statistically significant (P<0.05). (2) The blood loss at 6 h and 24 h after delivery in the experimental group were less than those in the control group, and the differences were statistically significant (all P<0.05). There were no significant differences between the two groups in the incidence of PPH, the proportion of additional use of uterine contraction drugs, hemostatic drugs or other hemostatic measures at 2 h and 24 h after delivery, the proportion requiring blood transfusion, and the proportion of prolonged hospital stay due to poor uterine involution (all P>0.05). (3) Adverse reactions occurred in 2 cases (1.4%, 2/148) in the experimental group and 1 case (0.7%, 1/150) in the control group. There was no significant difference between the two groups (P>0.05). The systolic blood pressure within 2.0 h and diastolic blood pressure within 1.5 h of drug administration in the experimental group were higher than those in the control group, and the differences were statistically significant (P<0.05), but the blood pressure of the two groups were in the normal range. Conclusion: The use of ergometrine injection in CS could reduce the amount of PPH, which is safe and feasible.


Asunto(s)
Hemostáticos , Hemorragia Posparto , Embarazo , Femenino , Humanos , Hemorragia Posparto/prevención & control , Ergonovina/uso terapéutico , Oxitocina/uso terapéutico , Cesárea , Placenta
7.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(10): 1423-1428, 2022 Oct 06.
Artículo en Zh | MEDLINE | ID: mdl-36274608

RESUMEN

Objective: To explore the impact of environmental temperature exposure on eczema visits. Methods: Eczema clinic data from January 1, 2016 to December 31, 2019 were collected from the Huizhou Dermatology Hospital, and data on meteorological factors (average daily temperature and relative humidity) for the same period were derived from 86 meteorological stations of the Guangdong Provincial Climate Center. A distributed lag nonlinear model (DLNM) was used to assess the lagged effect of environmental temperature exposure on eczema, and a natural smooth spline function was used to control the nonlinear confounding of humidity. Results: There were 254 053 eczema outpatient visits at the Huizhou Dermatology Hospital within four years, with an average of 173.89 visits per day. The relationship between daily average temperature and the number of visits was non-linear (U shape). The risk of eczema increased by 2.20% (1.19%-3.21%) for every 1 ℃ decrease for the low temperature, and increased by 2.35% (1.24%-3.5%) for every 1 ℃ increase for the high temperature. The effect of high temperature was greater than that of low temperature. In all cases, 1.60% (0.44%-2.68%) of eczema outpatient visits were attributed to low temperature and the attributable number was 4 065 (1 128-6 798), while 6.33% (1.40%-10.87%) of eczema outpatient visits were due to high temperature and the attributable number was 16 082 (3 557-27 616). Conclusion: Both high temperature and low temperature are associated with increased risk of eczema.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Eccema , Humanos , Contaminación del Aire/efectos adversos , Temperatura , Pacientes Ambulatorios , Ciudades , Eccema/epidemiología , China/epidemiología , Contaminantes Atmosféricos/análisis
8.
Zhonghua Wai Ke Za Zhi ; 60(2): 154-158, 2022 Feb 01.
Artículo en Zh | MEDLINE | ID: mdl-35012275

RESUMEN

Objective: To examine the safety and feasibility of gasless submental-transoral combined appoach endoscopic thyroidectomy for papillary thyroid carcinoma (PTC). Methods: A retrospective analysis of the clinical data of 41 patients with PTC who underwent the gasless submental-transoral combined appoach endoscopic thyroidectomy at the Department of Head and Neck Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine from November 2020 to April 2021. There were 5 males and 36 females with the age of (35.0±8.7) years (range: 19 to 58 years). A horizontal incision with a length of 2.0 cm is made under the chin as an observation hole, a 10 mm Trocar and a self-developed retractor are inserted, and two 5 mm longitudinal incisions are made on the labial side in the vestibule of the oral cavity as an operation hole, each inserting a 5 mm Trocar, the operation direction is from the cranial side to the caudal side. The sensation of the lower lip and chin was measured on the first day and one month postoperative. The operation time, hospital stay, the number of lymph nodes dissected and postoperative complications were recorded. Results: Surgical procedures in all cases were successfully completed under endoscopic approach without transfering to open surgery. The operation time was (99±34) minutes (range: 50 to 180 minutes) and the postoperative hospital stay was (3.4±2.2) days (range: 2 to 16 days). The maximum diameter of PTC was (7.6±5.8) mm (range: 2 to 30 mm), and the number of lymph nodes of the central compartment dissection was 6(5) (M(IQR)) (range: 1 to 25). The duration of follow-up is 1 month after operation, and the follow-up method is adopted in outpatient clinic. Postoperation complications included 2 cases of transient hypoparathyroidism, One case of recurrent laryngeal nerve injury (continue to follow up to assess whether it is a temporary injury). Postoperative minor chyle leak, seroma, and local redness and swelling in 1 case each were cured after conservative treatment. 1 case of transient minor numbness of the lower lip was observed. No permanent hypoparathyroidism, postoperative bleeding and numbness of the chin was observed. Conclusion: The gasless submental-transoral combined appoach endoscopic thyroidectomy is a feasible approach in selected PTC patients and has clinical application value.


Asunto(s)
Neoplasias de la Tiroides , Tiroidectomía , Adulto , Endoscopía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Disección del Cuello , Estudios Retrospectivos , Cáncer Papilar Tiroideo/cirugía , Neoplasias de la Tiroides/cirugía , Adulto Joven
9.
Phys Rev Lett ; 126(8): 086802, 2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33709762

RESUMEN

Mesoscopic conductance fluctuations are a ubiquitous signature of phase-coherent transport in small conductors, exhibiting universal character independent of system details. In this Letter, however, we demonstrate a pronounced breakdown of this universality, due to the interplay of local and remote phenomena in transport. Our experiments are performed in a graphene-based interaction-detection geometry, in which an artificial magnetic texture is induced in the graphene layer by covering a portion of it with a micromagnet. When probing conduction at some distance from this region, the strong influence of remote factors is manifested through the appearance of giant conductance fluctuations, with amplitude much larger than e^{2}/h. This violation of one of the fundamental tenets of mesoscopic physics dramatically demonstrates how local considerations can be overwhelmed by remote signatures in phase-coherent conductors.

10.
Zhonghua Wai Ke Za Zhi ; 59(6): 477-483, 2021 Jun 01.
Artículo en Zh | MEDLINE | ID: mdl-34102731

RESUMEN

Objective: To explore the imaging features and clinical effect of accordion maneuver in promoting the bone healing at the docking site after tibial transport under ultrasonic monitoring. Methods: Retrospective analysis was conducted on the clinical data of 16 patients with tibial bone transport who were admitted to the Department of Orthopedics, the second Hospital of Shanxi Medical University from May 2018 to October 2019. All the patients were treated with accordion maneuver to promote bone healing at the docking site under ultrasound monitoring. There were 14 males and 2 females, aged (45.3±14.3) years (range: 6 to 61 years). Before tibial bone transport, the length of the tibial defect of 16 patients was (6.0±2.6) cm (range: 2.0 to 12.1 cm). The operation steps of accordion maneuver were as follows: pressurization for 2 weeks, suspension for 12 days, distraction for 2 weeks, retraction for 2 weeks, and then stop the operation to consolidate the bone mineralization. During accordion treatment, ultrasound was used to monitor the size of hematoma, Adler grade of blood flow signal and the changes of new callus in and around the docking site. X-ray was performed to monitor bone healing at the docking site. Pearson correlation coefficient was used to analyze the correlation between the size of hematoma, the resistance index of blood flow signal and the bone healing time of the docking site. Paley healing criterion was used to evaluate the bone healing and functional recovery of the patients. Results: During accordion maneuver, ultrasound examination showed that the Adler grade of blood flow signals around the docking site increased gradually before retraction and then decreased gradually, but the degree of callus mineralization continued to increase gradually. After 2 weeks of pressure on the docking site, hematoma was observed in 14 patients by ultrasound examination. X-ray showed that all docking sites had bony healing, with the healing time of (30.8±4.9) weeks (range: 23 to 40 weeks).The size of the hematoma was negatively correlated with the healing time of the docking site (r=-0.819,P<0.01). No hematoma was found in 2 patients, and after continuous observation for 20 weeks, there was still no obvious callus connection at the docking site. After bone cortical removal, ultrasound examination showed hematoma formed at the docking site. Accordion maneuver was continued, and the docking site healed at 30 and 32 weeks after surgery, respectively. There was a negative linear correlation between hematoma size at 2 weeks of compression and the blood flow resistance index at 2 weeks of retraction in 16 patients (r=-0.801, P<0.01). The patients were followed-up for (14.5±3.2) months (range: 10.6 to 20.2 months). At the last follow-up, 12 patients were evaluated as excellent and 4 were evaluated as good by Paley healing criteria. Conclusion: The distraction and compression stress applied in accordion maneuver can promote bone healing at the docking site, and ultrasound can monitor early signs of bone healing at the docking site to help determine the tendency of bone healing.


Asunto(s)
Fracturas de la Tibia , Ultrasonido , Femenino , Curación de Fractura , Humanos , Masculino , Radiografía , Estudios Retrospectivos , Tibia/diagnóstico por imagen , Resultado del Tratamiento , Cicatrización de Heridas
11.
Phys Rev Lett ; 125(21): 217002, 2020 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-33274977

RESUMEN

We studied the electronic Raman spectra of (Li_{1-x}Fe_{x})OHFeSe as a function of light polarization and temperature. In the B_{1g} spectra alone we observe the redistribution of spectral weight expected for a superconductor and two well-resolved peaks below T_{c}. The nearly resolution-limited peak at 110 cm^{-1} (13.6 meV) is identified as a collective mode. The peak at 190 cm^{-1} (23.6 meV) is presumably another collective mode since the line is symmetric and its energy is significantly below the gap energy observed by single-particle spectroscopies. Given the experimental band structure of (Li_{1-x}Fe_{x})OHFeSe, the most plausible explanations include conventional spin-fluctuation pairing between the electron bands and the incipient hole band and pairing between the hybridized electron bands. The absence of gap features in A_{1g} and B_{2g} symmetry favors the second case. Thus, in spite of various differences between the pnictides and chalcogenides, this Letter demonstrates the proximity of pairing states and the importance of band structure effects in the Fe-based compounds.

12.
Nature ; 510(7505): 427-31, 2014 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-24814342

RESUMEN

Sulphur is an essential element for life and is ubiquitous in living systems. Yet how the sulphur atom is incorporated into many sulphur-containing secondary metabolites is poorly understood. For bond formation between carbon and sulphur in primary metabolites, the major ionic sulphur sources are the persulphide and thiocarboxylate groups on sulphur-carrier (donor) proteins. Each group is post-translationally generated through the action of a specific activating enzyme. In all reported bacterial cases, the gene encoding the enzyme that catalyses the carbon-sulphur bond formation reaction and that encoding the cognate sulphur-carrier protein exist in the same gene cluster. To study the production of the 2-thiosugar moiety in BE-7585A, an antibiotic from Amycolatopsis orientalis, we identified a putative 2-thioglucose synthase, BexX, whose protein sequence and mode of action seem similar to those of ThiG, the enzyme that catalyses thiazole formation in thiamine biosynthesis. However, no gene encoding a sulphur-carrier protein could be located in the BE-7585A cluster. Subsequent genome sequencing uncovered a few genes encoding sulphur-carrier proteins that are probably involved in the biosynthesis of primary metabolites but only one activating enzyme gene in the A. orientalis genome. Further experiments showed that this activating enzyme can adenylate each of these sulphur-carrier proteins and probably also catalyses the subsequent thiolation, through its rhodanese domain. A proper combination of these sulphur-delivery systems is effective for BexX-catalysed 2-thioglucose production. The ability of BexX to selectively distinguish sulphur-carrier proteins is given a structural basis using X-ray crystallography. This study is, to our knowledge, the first complete characterization of thiosugar formation in nature and also demonstrates the receptor promiscuity of the A. orientalis sulphur-delivery system. Our results also show that co-opting the sulphur-delivery machinery of primary metabolism for the biosynthesis of sulphur-containing natural products is probably a general strategy found in nature.


Asunto(s)
Actinomycetales/enzimología , Actinomycetales/genética , Proteínas Portadoras/metabolismo , Ligasas/química , Azufre/metabolismo , Tioazúcares/metabolismo , Actinomycetales/metabolismo , Proteínas Portadoras/química , Dominio Catalítico , Genoma Bacteriano/genética , Ligasas/genética , Ligasas/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Terciaria de Proteína
13.
Herz ; 45(4): 335-346, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30128908

RESUMEN

BACKGROUND: Our aim was to evaluate the effect of urinary trypsin inhibitors (UTI) on interleukin, tumor necrosis factor-α (TNF-α), and polymorphonuclear neutrophil elastase (PMNE) levels as well as on pulmonary function in patients undergoing cardiopulmonary bypass. MATERIALS AND METHODS: We searched the following databases for relevant studies: PubMed, Medline (Ovid SP), Cochrane Library, Wanfang Data, China Biology Medicine Database, Chinese Periodical Database, China Knowledge Resource Integrated Database, and Chinese Clinical Trial Registry. Two investigators independently collected the data and assessed the quality of each study. RevMan 5.3 was used for the meta-analysis. RESULTS: In total, 15 randomized controlled trials (646 patients) met the inclusion criteria. There was a significant decrease in TNF-α, interleukin-6 (IL-6), IL-8, and PMNE levels at 6 h and 24 h after UTI treatment and an increase in IL-10 levels; additionally, there was a decrease in respiratory index and an improvement in the oxygenation index. Nevertheless, UTI treatment did not affect the length of intensive care unit stay, alveolar-arterial oxygen partial pressure difference, adverse lung events, or hospital mortality. Because of the high heterogeneity of the included trials, the results should be assessed carefully. CONCLUSION: UTI treatment can suppress proinflammatory cytokine elevation and upregulate the release of anti-inflammatory mediators, thereby reducing pulmonary injury and improving pulmonary function after cardiopulmonary bypass.


Asunto(s)
Puente Cardiopulmonar , Glicoproteínas , Interleucinas , Pulmón , Inhibidores de Tripsina , China , Glicoproteínas/uso terapéutico , Humanos , Interleucinas/uso terapéutico , Pulmón/efectos de los fármacos , Pulmón/fisiología , Ensayos Clínicos Controlados Aleatorios como Asunto , Inhibidores de Tripsina/uso terapéutico
14.
Ecotoxicol Environ Saf ; 190: 110128, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31891838

RESUMEN

Over the last few decades, the threat posed to biodiversity and ecosystem function by atmospheric nitrogen (N) deposition has been increasingly recognized. The disturbed nutrient balance and species composition of plants induced by higher N deposition can impact the biodiversity of the organisms that consume the plants. In this research, we implemented several experiments to estimate the effects of increased N deposition on the growth, survival, and nutrients of the dominant epiphytic lichens in the subtropical mountains in Central China to assess the lichen food amount and nutritional quality for two endangered primates endemic to China. Our results indicated that the thallus growth and propagule survival of the lichens were significantly decreased when nitrogen addition changed from 6.25 to 50.0 kg N·ha-1·y-1; it was also shown that lichen biomass could be decreased by 11.2%-70.2% when the deposition addition exceeded 6.25 kg N·ha-1·y-1. Further, our study revealed that increased nitrogen deposition also reduced the nutritional quality of the lichens via reducing the soluble protein and soluble sugar levels and increasing the fiber content, which would substantially affect the diet selection of the plants consumers in the region, particularly the populations of the two lichen-eating endangered primate species, Rhinopithecus roxellana and R. bieti. Our experimental study suggested that the nitrogen pollution derived from anthropogenic activities could cause cascading effects for the whole forest ecosystem of Central China; thus, more studies about nitrogen deposition in this region are required.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Líquenes/química , Nitrógeno/análisis , Animales , Atmósfera , Biodiversidad , Biomasa , China , Ecosistema , Contaminación Ambiental , Abastecimiento de Alimentos , Bosques , Líquenes/metabolismo , Nitrógeno/metabolismo , Primates
15.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(4): 362-366, 2020 Apr 06.
Artículo en Zh | MEDLINE | ID: mdl-32083409

RESUMEN

Objective: To evaluate the exported risk of COVID-19 from Hubei Province and the imported risk in various provinces across China. Methods: Data of reported COVID-19 cases and Baidu Migration Indexin all provinces of the country as of February 14, 2020 were collected. The correlation analysis between cumulative number of reported cases and the migration index from Hubei was performed, and the imported risks from Hubei to different provinces across China were further evaluated. Results: A total of 49 970 confirmed cases were reported nationwide, of which 37 884 were in Hubei Province. The average daily migration index from Hubei to other provinces was 312.09, Wuhan and other cities in Hubei were 117.95 and 194.16, respectively. The cumulative COVID-19 cases of provinces was positively correlated with the migration index derived from Hubei Province, also in Wuhan and other cities in Hubei, with correlation coefficients of 0.84, 0.84, and 0.81. In linear model, population migration from Hubei Province, Wuhan and other cities in Hubei account for 71.2%, 70.1%, and 66.3% of the variation, respectively. The period of high exported risk from Hubei occurred before January 27, of which the risks before January 23 mainly came from Wuhan, and then mainly from other cities in Hubei. Hunan Province, Henan Province and Guangdong Province ranked the top three in terms of cumulative imported risk (the cumulative risk indices were 58.61, 54.75 and 49.62 respectively). Conclusion: The epidemic in each province was mainly caused by the importation of Hubei Province. Taking measures such as restricting the migration of population in Hubei Province and strengthening quarantine measures for immigrants from Hubei Province may greatly reduce the risk of continued spread of the epidemic.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Medición de Riesgo , Betacoronavirus , COVID-19 , China/epidemiología , Ciudades , Humanos , Modelos Lineales , Pandemias , SARS-CoV-2
16.
Fa Yi Xue Za Zhi ; 36(3): 374-378, 2020 Jun.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-32705853

RESUMEN

ABSTRACT: MicroRNA (miRNA) belongs to a class of endogenous non-coding small RNA molecules with a length of 18-24 nucleotides. The expression of miRNA is highly conservative, has time sequence and is highly tissue-specific. MiRNA could not be easily degraded by ribonuclease, and is resistant to changes in environmental factors such as temperature and pH value. Moreover, miRNA can even be detected in corrupt tissue. As a result, miRNA has broad application prospects in many fields of forensic medicine such as source identification of body fluid and estimation of cause of death. This article briefly summarizes the application of miRNA in forensic practice, such as body fluid identification, determination of postmortem interval and cause of death analysis.


Asunto(s)
Medicina Legal , Marcadores Genéticos , MicroARNs , Genética Forense , Humanos , MicroARNs/genética
17.
Fa Yi Xue Za Zhi ; 36(1): 99-103, 2020 Feb.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-32250087

RESUMEN

ABSTRACT: The number of death from insulin overdose, including accidental poisoning, suicide and homicide, is increasing these years. The forensic diagnosis of death from insulin overdose is a tough task. Glucose is the main energy source of the brain. Therefore, hypoglycemic brain damage is considered to be the main reason of death from insulin overdose. Recently, research of hypoglycemic brain damage caused by insulin overdose is gradually being paid attention in the field of forensic medicine. This paper summarizes the neuropathologic changes, pathophysiologic process and potential neural molecular markers of hypoglycemic brain damage caused by insulin overdose in terms of forensic neuropathology, providing reference for the research and practice in forensic medicine related fields.


Asunto(s)
Encéfalo , Sobredosis de Droga , Humanos , Hipoglucemiantes , Insulina , Neuropatología
18.
Acta Virol ; 63(1): 121-125, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30879322

RESUMEN

The H8 subtype viruses are rarely isolated from wild ducks. Shanghai is one of the important wintering or stopover sites on the East Asia-Australia Migration Flyway. An influenza virus, subtype H8N4, was firstly isolated from a common teal (Anas crecca) in Shanghai during 2017-2018 in this study. To clarify the genetic characteristics of the H8N4 virus, the whole genome sequences were analyzed. Phylogenetic analysis of the hemagglutinin and neuraminidase genes showed that they shared highest nucleotide identity (99.19%-99.64%) with the Japan duck-origin H8N4 virus collected in 2016 (A/duck/Aichi/231003/2016) and belonged to the Eurasian-like avian lineage. Six other genes of the H8N4 isolated virus were all highly similar to the corresponding genes of a wide range of AIV subtypes including H9N2, H5N7, H3N8, H1N2, H4N6 and H1N1. The results indicated that the H8N4 virus was a multiple reassortant virus. The study emphasized that the continuous surveillance of influenza virus in wild birds should be strengthened. Keywords: avian influenza virus; H8N4; phylogenetic analysis; Shanghai.


Asunto(s)
Virus de la Hepatitis A , Gripe Aviar , Animales , Aves , China , Patos , Virus de la Hepatitis A/clasificación , Virus de la Hepatitis A/genética , Virus de la Hepatitis A/aislamiento & purificación , Subtipo H1N1 del Virus de la Influenza A/clasificación , Subtipo H1N1 del Virus de la Influenza A/genética , Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Subtipo H3N8 del Virus de la Influenza A/clasificación , Subtipo H3N8 del Virus de la Influenza A/genética , Subtipo H3N8 del Virus de la Influenza A/aislamiento & purificación , Subtipo H9N2 del Virus de la Influenza A , Gripe Aviar/virología , Filogenia , Virus Reordenados/clasificación , Virus Reordenados/genética , Virus Reordenados/aislamiento & purificación
19.
Zhonghua Yi Xue Za Zhi ; 99(42): 3318-3322, 2019 Nov 12.
Artículo en Zh | MEDLINE | ID: mdl-31715668

RESUMEN

Objective: To summarize the application of radial artery (RA) as the second arterial graft in coronary artery bypass grafting (CABG). Methods: From January 1, 2015 to June 11, 2019, the clinical data of all patients undergoing CABG in TEDA International Cardiovascular Hospital was retrospectively reviewed. The patients who underwent RA grafting were included. The application of RA, internal mammary artery (IMA) and the saphenous vein, their target vessels, and the operative results were analyzed. Results: A total of 2 901 patients underwent CABG. Of those, 208 patients (7.2%) had RA grafting, with 197 males and 11 females. The average age was (53±8) years old and the average grafts per patient was 3.79. The target vessel for RA was first obtuse marginal (OM, 102 cases), first diagonal (50 cases), right coronary artery (RCA) or posterior descending artery (PDA) (40 cases), intermediate (22 cases), respectively. Among those, 172 were single distal anastomosis with the proximal end anastomosed to the ascending aorta (168 cases), saphenous vein (SV) graft (3 cases) and IMA (1 case). Seventy-two patients accept sequential grafting with the proximal to the ascending aorta (58 cases), SV graft (13 cases) and IMA (1 case). The left IMA was mainly anastomosed to left descending artery (LAD) (188 cases) and diagonal (10 cases). The target vessels for SV were remaining coronary arteries when the IMA and RA were used. The operative time was (5.0±1.5) h. The hospital stay was (17.4±6.4) d. There were 6 cases undergoing exploratory thoracotomy for bleeding (5 cases) or hemodynamic instability due to ventricular arrhythmia (1 case). There was no death. All patients were successfully discharged. Conclusions: Use of the RA and IMA with additional SV for CABG exhibits good results in the Chinese patients. Currently available clinical protocols are effective and safe.


Asunto(s)
Arterias Mamarias , Arteria Radial , Puente de Arteria Coronaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Arteria Radial/cirugía , Estudios Retrospectivos , Vena Safena , Resultado del Tratamiento
20.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(6): 645-652, 2019 Jun 06.
Artículo en Zh | MEDLINE | ID: mdl-31177766

RESUMEN

Dioxins, polybrominated diphenyl ethers, and benzo(a)pyrene are common organic pollutants in food. They have been of concern to academics and government administrations due to high residue and persistence, easy accumulation and strong harmful effects. The National Research Council of the United States of America published Toxicity Testing in the 21st Century: A Vision and Strategy in 2007, which proposed a new concept of toxicity testing that toxicity testing should take full consideration of population exposure data and base on in vitro tests, human cell lines, toxicity pathways and high-throughput screening. Meanwhile, systems biology, bioinformatics and rapid assay technologies will be used to better understand toxicity pathways-the cellular response pathways that can lead to adverse health effects when sufficient perturbing induced by chemicals exposure. The new toxicity testing strategy has changed the traditional testing pattern and has brought a wide impact on the international relevant fields. The European Union, the World Health Organization, and the United States Environmental Protection Agency, the Food and Drug Administration, and the National Center for Toxicological Research have organized relevant discussions and exploratory studies to address the new toxicity testing concept and how to evaluate and utilize the results of traditional toxicity test researches. Compared to the discussion, 'whether to do it', ten years ago, the question, 'how to do it', has become the concern of the current discussion. Therefore, how to respond to the concept of toxicity testing and how to effectively utilize and excavate traditional toxicity test data have been the focus of multi-disciplines and interdisciplinary academia such as toxicology, food hygiene and environmental science. Therefore, this article provides an overview of the exposure levels of dioxin, polybrominated diphenyl ethers and benzo[a]pyrene, which are typical persistent organic pollutants in food in China and the current research status of toxic pathways based on whole animal experiments. The exposure level, toxic effect and toxicity mechanism of three contaminants are analyzed and summarized in order to provide basis for future results based on the 21st century toxicity test compared with traditional tests and data mining analysis of these two kinds of data. Meanwhile, it also lays the foundation for the establishment of a toxicity testing framework based on exposure characteristics, toxic pathways, and biomarkers.


Asunto(s)
Contaminantes Ambientales , Contaminación de Alimentos , Dibenzodioxinas Policloradas , Animales , China , Contaminantes Ambientales/análisis , Contaminantes Ambientales/toxicidad , Humanos , Compuestos Orgánicos/análisis , Compuestos Orgánicos/toxicidad , Dibenzodioxinas Policloradas/análisis , Dibenzodioxinas Policloradas/toxicidad , Investigación , Pruebas de Toxicidad
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