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1.
Nature ; 598(7880): 267-271, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34645999

RESUMO

The event rate, energy distribution and time-domain behaviour of repeating fast radio bursts (FRBs) contain essential information regarding their physical nature and central engine, which are as yet unknown1,2. As the first precisely localized source, FRB 121102 (refs. 3-5) has been extensively observed and shows non-Poisson clustering of bursts over time and a power-law energy distribution6-8. However, the extent of the energy distribution towards the fainter end was not known. Here we report the detection of 1,652 independent bursts with a peak burst rate of 122 h-1, in 59.5 hours spanning 47 days. A peak in the isotropic equivalent energy distribution is found to be approximately 4.8 × 1037 erg at 1.25 GHz, below which the detection of bursts is suppressed. The burst energy distribution is bimodal, and well characterized by a combination of a log-normal function and a generalized Cauchy function. The large number of bursts in hour-long spans allows sensitive periodicity searches between 1 ms and 1,000 s. The non-detection of any periodicity or quasi-periodicity poses challenges for models involving a single rotating compact object. The high burst rate also implies that FRBs must be generated with a high radiative efficiency, disfavouring emission mechanisms with large energy requirements or contrived triggering conditions.

3.
Zhonghua Yi Xue Za Zhi ; 102(6): 435-441, 2022 Feb 15.
Artigo em Zh | MEDLINE | ID: mdl-35144344

RESUMO

Objective: To explore the time trends of H. pylori infection and related drug use in patients with peptic ulcer bleeding (PUB) in recent ten years. Methods: PUB patients in Peking University Third Hospital from 2010 to 2019 were included. Time trends of H. pylori infection, related drugs (non-steroidal anti-inflammatory drugs, aspirin, antiplatelet drugs, anticoagulant drugs, glucocorticoids) use and non-H. pylori-non-drug ulcer in PUB patients were analyzed. Results: A total of 1 140 PUB patients were included from 2010 to 2019 (including 925 males and 215 females). The age M(Q1,Q3)was 53.5 (33.0, 66.0) years, with 833 patients <65 years old. The positive rates of H. pylori were 79.3%, 75.7%, 73.1%, 71.6%, 77.0%, 70.4%, 69.7%, 63.1%, 51.4%, 50.9%, respectively, showing a decreasing trend (χ²=32.386, P<0.001), and the decreasing trends were significant in different ulcer location, age and gender subgroups(all P<0.05). The proportions of PUB patients using at least one of the above drugs were 23.1%, 28.6%, 34.0%, 39.5%, 33.8%, 35.9%, 28.7%, 39.8%, 40.9%, 41.8%, respectively, showing an increasing trend (χ²=6.857, P=0.009), and the proportions of patients with antiplatelet drugs and anticoagulant drugs history showed increasing trends. The proportions of non-H. pylori-non-drug patients were 12.3%, 22.1%, 14.6%, 13.2%, 7.7%, 13.0%, 16.9%, 18.7%, 22.6% and 20.9%, respectively, showing an increasing trend (χ²=4.808, P=0.028). Accordingly, the proportions of elderly (≥65 years old) patients (χ²=4.608, P=0.032) and large ulcer (≥2 cm) patients (χ²=8.173, P=0.004) showed increasing trends. Conclusion: In the last decade, the positive rate of H. pylori in PUB patients showed a decreasing trend, while the proportions of patients with antiplatelet drugs and anticoagulant drugs history and the proportion of non-H. pylori-non-drug patients showed increasing trends.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Úlcera Péptica , Preparações Farmacêuticas , Idoso , Anti-Inflamatórios não Esteroides/uso terapêutico , Feminino , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/epidemiologia , Hospitais , Humanos , Masculino
4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(1): 9-14, 2022 Jan 06.
Artigo em Zh | MEDLINE | ID: mdl-34954955

RESUMO

The risk of plague epidemics and relapse of various types of plague foci persists in Inner Mongolia Autonomous Region. For Marmota sibirica plague foci, the animal plague has not been found but antibody has been detected positive. Nowadays, Marmota sibirica has been increasing in population and distribution in China. In bordering countries Mongolia and Russia, the animal plague has been continuously prevalent. For Spermophilus dauricus plague foci, the animal plague has been taken place now and then. Compared to the above foci, the animal plague is most prevalent in Meriones unguiculatus plague foci and frequently spread to humans. Due to higher strain virulence and historical disaster in Marmota sibirica plague foci and Spermophilus dauricus plague foci, plague prevention and control should be strengthened on these foci. In addition to routine surveillance, epidemic dynamics need to be further monitored in these two foci, in order to prevent their relapse and spread to humans.


Assuntos
Epidemias , Peste , Yersinia pestis , Animais , China/epidemiologia , Humanos , Peste/epidemiologia , Peste/prevenção & controle , Prevalência , Sciuridae
5.
Zhonghua Yi Xue Za Zhi ; 101: 1875-1881, 2021 Jun 24.
Artigo em Zh | MEDLINE | ID: mdl-34192847

RESUMO

Objective: To evaluate the effectiveness of thermal ablation in the treatment of human papillomavirus (HPV) infection and cervical intraepithelial neoplasia (CIN) in Chinese women. Methods: The high-risk HPV-positive women aged 20-65 who were detected through a cervical cancer screening project implemented in three rural sites (Etuoke counties in Inner Mongolia, Xiangyuan and Yangcheng counties in Shanxi Province) and one urban site (Shenzhen) in China were included in this prospective study. Follow up evaluation was performed on HPV positive women who underwent thermal ablation (n=166) as well as received no treatment (n=2 716) in cervical cancer screening program. For women with thermal ablation treatment, HPV test and cytology were used for follow-up with the interval of 6 months or longer after treatment. For women without treatment, HPV test was used for annual follow-up. Women with positive results in either of the HPV tests or abnormal cytology were referred for a colposcopy or biopsy if necessary. The HPV clearance rate and the cure rate of CIN were compared between the two groups. Results: A total of 152 women treated with thermal ablation and 2 539 women without treatment reported for follow-up evaluation with the age M(Q1, Q3) of 42 (36, 48) and 47 (41, 54) years old, and the median time to follow-up time of 23.4 (12.4, 24.5) and 23.5 (12.4, 24.0)months, respectively. The HPV clearance rate in women undergoing thermal ablation was significantly higher than that in women with no treatment (73.0% vs 46.1%, P<0.001). The HPV16, HPV52 and HPV58 clearance rates among women receiving thermal ablation were higher than that in women without treatment with the OR (95%CI) of 2.8 (1.3-6.1), 3.2 (1.3-7.9) and 5.8 (2.1-15.6). For women with histologically confirmed CIN at baseline, cure rates were 77.4%(n=72) for thermal ablation. Cure rates of the thermal ablation were 81.0%(n=47) for CIN grade one (CIN1) and 71.4% (n=25) for CIN grade two or worse (CIN2+). Conclusions: Thermal ablation is effective to clear the HPV infection as well as to treat CIN. Particularly for the HPV genotypes with the paramount attributable proportion to cervical cancer and precancerous in China, the HPV clearance rate was significantly higher than that reported in the women without treatment.

6.
Zhonghua Fu Chan Ke Za Zhi ; 56(11): 788-795, 2021 Nov 25.
Artigo em Zh | MEDLINE | ID: mdl-34823292

RESUMO

Objective: To study the difference between BRCA gene mutations in hereditary breast and ovarian cancer syndrome (HBOC) and in sporadic ovarian cancer (SOC). Methods: This study was for exploratory research, the inclusion criteria were 284 patients with ovarian cancer admitted at Shanxi Provincial Cancer Hospital from November 2018 to December 2019, with high-throughput DNA sequencing including the full coding regions and exon-intron link regions of BRCA1 and BRCA2 gene. Pathogenic mutations in the BRCA gene of patients with ovarian cancer were collected and mutation site analysis was performed to compare phenotypic differences in pathogenic mutations between HBOC syndrome and SOC patients. Results: (1) Of the 284 ovarian cancer patients, seventy-seven had BRCA pathogenic mutations with a mutation rate of 27.1% (77/284), with BRCA1 mutation rate of 19.7% (56/284), BRCA2 gene 6.7% (19/284) and BRCA1/2 common mutation rate of 0.7% (2/284). Of the 284 patients with ovarian cancer, the pathogenic mutation rate in the BRCA gene in HBOC syndrome patients was 43.8% (32/73), which were significantly higher than that in SOC patients [21.3% (45/211); χ²=13.905, P<0.01]. Among BRCA1 gene mutation, the mutation rate in HBOC syndrome was higher than that of SOC [87.5% (28/32) vs 62.2% (28/45)], the BRCA2 gene mutation rate in patients with HBOC syndrome was lower than that in SOC patients [6.2% (2/32) vs 37.8% (17/45)], and there were statistically significant differences (all P<0.05). Two of the 77 patients with pathogenic mutations in the BRCA gene were multisite mutations, including one simultaneous two site mutation, one simultaneous three site mutation. There were 80 mutation sites with frameshift deletion mutations (55.0%, 44/80) and nonsense mutations (31.2%, 25/80). (2) Of the 73 patients with HBOC syndrome, 32 cases had pathogenic mutations in BRCA gene, including 28 cases in BRCA1, mainly in exon 11 and 24 (9 and 7 cases, respectively), and only two cases in BRCA2, both in exon 11; another two had multiple locus mutations. Of the 211 patients with SOC, 45 cases had pathogenic mutants in BRCA gene, including 28 cases in BRCA1, mainly in exon 11 and 24 (15 and 2 cases, respectively), and 17 cases in BRCA2, mainly in exon 11 (11 cases). (3) Thirty-four pathogenic mutation sites in BRCA gene were found newly, twenty of them were located in the BRCA1 gene, including a locus located on the intron 6, 301+1G>A, and the remaining 19 sites were located on the exons, including 283_286delCTTG, 68_69delAG, 132C>T, 514_547+3del37, 742delA, 1126_1129delAATA, 1196delA, 1352_1364del, 1465G>T, 2171delC, 2341G>T, 3359_3363delTTAAT, 4085_4086ins11, 4161_4162delTC, 4165_4166delAG, 4258G>T, 4338_4339del8insAGAA, 4468G>T, and 4783delA; fourteen sites were located in the BRCA2 gene, including a locus located on the intron 7, 631+1G>A, and the remaining 13 sites were located on the exons, including 2648delT, 2914A>T, 2950_2951insG, 4357+1G>A, 5054C>T, 5257A>T, 5291_5292insTC, 5913delT, 3593delA, 6091_6092insA, 6135_6136delTT, 7452delT, 9097_9098insA. A tal of 28 repeat mutations were located in the BRCA1 gene; among them, the site 5470_5477del8 was repeated 6 times, while 3 times in 981_982delAT. Conclusions: Patients with HBOC syndrome have a significantly higher rate of pathogenic mutation in the BRCA gene than that in patients with SOC. BRCA gene pathogenic mutation sites in HBOC syndrome patients occur commonly in exon 11 and 24 of BRCA 1 gene, while SOC patients occur mainly in exon 11 and 24 of BRCA1 gene and exon 11 of BRCA2 gene. The two loci of BRCA1∶5470_5477del8, BRCA1∶981_982delAT may be ancestor mutations in Chinese ovarian cancer patients, and 34 newly discovered pathogenic mutations in the BRCA gene, enriching the BRCA gene mutation spectrum in the Chinese population.


Assuntos
Neoplasias da Mama , Síndrome Hereditária de Câncer de Mama e Ovário , Neoplasias Ovarianas , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Feminino , Genes BRCA2 , Predisposição Genética para Doença , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Humanos , Mutação , Neoplasias Ovarianas/genética
7.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(10): 1228-1231, 2021 Oct 06.
Artigo em Zh | MEDLINE | ID: mdl-34706509

RESUMO

Based on the data from China Health and Nutrition Survey (CHNS), 840 girls aged 6-15 years who had information about menarche and participated in dietary survey at least once within 1-5 years before onset of menarche between 1989 and 2015 were included in the study. The median age at baseline of the 840 participants was 10 (9, 11) years. The median age at menarche of the participants was 13 (12, 14) years. After adjusting for the age of birth, place of residence, body mass index Z-score, physical activity level and annual household income per capita, the average age of menarche was advanced by 0.036 (95%CI: -0.068, -0.004) years for every 10 g increase in daily fat intake before menarche. The average age at menarche was 0.008 (95%CI: -0.014, -0.001) years earlier for every 1% increase in the daily energy supply ratio of fat before menarche.


Assuntos
Dieta , Menarca , Índice de Massa Corporal , Ingestão de Alimentos , Feminino , Humanos , Nutrientes , Estudos Prospectivos
8.
Colorectal Dis ; 22(11): 1528-1537, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32277562

RESUMO

AIM: The aim was to explore the diagnostic value of computed tomographic colonography (CTC) compared with conventional colonoscopy in individuals at high risk for colorectal cancer. METHOD: PubMed, Embase, the Cochrane Library and the Web of Science were searched by two independent reviewers for potentially eligible studies published up to 31 October 2018 that were based on a per-patient analysis. stata, meta-disc and revman were used to perform this meta-analysis. A random-effect model was used, and a subgroup analysis was conducted to explore the sources of heterogeneity. RESULTS: A total of 14 full-text articles, involving 3578 patients, were included in this meta-analysis. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and the area under the summary receiver operating characteristic curve of CTC for detecting polyps ≥ 6 mm were 0.87 (95% CI 0.83-0.90), 0.90 (95% CI 0.86-0.93), 9.08 (95% CI 6.28-13.13), 0.14 (95% CI 0.11-0.18) and 0.94 (95% CI 0.92-0.96), respectively. For polyps ≥ 10 mm, the pooled sensitivity, specificity, positive likelihood ratio and negative likelihood ratio of CTC were 0.91 (95% CI 0.86-0.94), 0.98 (95% CI 0.95-0.99), 40.36 (95% CI 19.16-85.03), 0.90 (95% CI 0.06-0.14) and 0.98 (95% CI 0.96-0.99), respectively. CONCLUSION: In this meta-analysis, CTC had high diagnostic accuracy for detecting polyps ≥ 6 mm and ≥ 10 mm in patients at high risk of developing colorectal cancer and it had a higher sensitivity and specificity for detecting polyps ≥ 10 mm than polyps ≥ 6 mm. However, the results should be used cautiously due to the significant heterogeneity.


Assuntos
Pólipos do Colo , Colonografia Tomográfica Computadorizada , Neoplasias Colorretais , Pólipos do Colo/diagnóstico por imagem , Colonoscopia , Neoplasias Colorretais/diagnóstico por imagem , Humanos , Sensibilidade e Especificidade , Tomografia
9.
Zhonghua Yi Xue Za Zhi ; 100(31): 2467-2469, 2020 Aug 18.
Artigo em Zh | MEDLINE | ID: mdl-32688457

RESUMO

Objective: To investigate the application of a modified scalp retractor in the craniotomy for intracranial aneurysms withlateral supraorbital approach. Methods: From January 2019 to April 2020, a total of 32 patients with anterior circulation aneurysms clipping by superior lateral orbital approach were selected from Beijing Tiantan Hospital and Peking University International Hospital. The subjects were randomly divided into the traditional scalp retractor group and the modified scalp retractor group utilizing a random number table, with 16 patients in each group. The number of intraoperative retractor adjustment, incision length, postoperative scalp necrosis rate, postoperative wound healing grade, postoperative neurosurgical satisfaction score and patients' satisfaction score for incision were compared between the two groups. Results: The number of retractor adjustment in the modified scalp retractors group was significantly less than that in the traditional scalp retractor group (10.1±2.2 vs 14.2±3.6, P<0.05) . Incision length was also significantly shorter than that of the conventional scalp retractor group ( (10.1±1.0) cm vs (13.9±0.9) cm, P<0.05) .Neurosurgeons were significantly more satisfied with modified scalp retractors than the traditional scalp retractors (8.1±0.9 vs 6.0±0.9, P<0.05). There was no significant difference in postoperative scalp necrosis rate between two groups (P>0.05). Conclusion: The modified scalp retractor group is superior to the traditional scalp retractor group in the craniotomy for intracranial aneurysms with later supraorbital approach, with shorter in cision, less retractor adjustment and shorter surgical time.


Assuntos
Craniotomia , Aneurisma Intracraniano/cirurgia , Humanos , Microcirurgia , Procedimentos Neurocirúrgicos , Período Pós-Operatório , Couro Cabeludo , Resultado do Tratamento
10.
Eur Cell Mater ; 37: 60-73, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30687909

RESUMO

Osteoinductive calcium phosphate (CaP) bone grafts have equivalent performance to autografts in repairing critical-size bone defects. The osteoinductive potential of CaP is linked to the size of the surface topographical features. In the present study, two novel biphasic calcium phosphate (BCP) bone grafts were synthesised with either sub-micron- (BCP<µm) or micron-scale (BCPµm) needle-shaped surface topography and compared to dimensionally similar tricalcium phosphate (TCP) with grain-shaped surface structures (TCP<µm and TCPµm). To clarify the possible function of the surface morphology (needle-like vs. grain-like) in initiating bone formation, the four CaP test materials were physicochemically characterised and implanted for 12 weeks in the dorsal muscle of beagles. The sub-micron needle-shaped topography of BCP<µm triggered earlier bone formation (3-6 weeks) as compared to the grain-shaped surface topography of TCP<µm, which formed bone at 6-9 weeks. After 12 weeks, the amount of induced bone formation in both materials was equivalent, based on histomorphometry. The micron-sized needle-shaped surface topography of BCPµm led to limited formation of new bone tissue, whereas its counterpart, TCPµm with grain-shaped surface topography, failed to trigger de novo bone formation. The relative strength of the parameters affecting CaP-driven bone induction was as follows: surface feature size > surface feature morphology > substrate chemistry. BCP materials with needle-shaped sub-micron surface topography gave rise to accelerated bone formation and slower rate of resorption than a comparable TCP. These characteristics may be translated to improve bone healing in orthotopic defects.


Assuntos
Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Osteogênese , Tamanho da Partícula , Adsorção , Animais , Calcificação Fisiológica/efeitos dos fármacos , Bovinos , Cães , Íons , Osteogênese/efeitos dos fármacos , Implantação de Prótese , Soroalbumina Bovina/metabolismo , Propriedades de Superfície
11.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(10): 1027-1031, 2019 Oct 06.
Artigo em Zh | MEDLINE | ID: mdl-31607050

RESUMO

Objective: To illuminate the epidemic characteristics of Yersiniosis among children in the central city of Beijing and the accuracy of current clinical diagnosis towards Yersiniosis. Methods: Etiological surveillance of diarrheal patients, a total of 3 493 cases, was performed in a children hospital in central area of Beijing from 2011 to 2018 continuously. Collected the epidemiological and clinical information of the cases, analyzed the clinical and etiological diagnosis for Yersiniosis and bacterial dysentery and compared the distribution of Yersiniosis cases with the different symptoms. Results: A total of 3 493 acute diarrhea cases distributed from the age of 6 months to 13 years old, M (P(25), P(75)) was 1.50 (0.75, 3.17) years old. The 28 cases were isolated Yersinia enterocolitica (isolation rate of 0.80%) and they could be diagnosed as Yersiniosis by etiology. The isolation peaked in May and February. A total of 85.71% (24/28) of Yersiniosis cases were under 5-year old. The children of 3-4 age group had the highest isolation rate (1.52%) while the rate (0.18%) of 0-1 age group was the lowest (P=0.025). The Yersinia enteroclitica isolation rates of diarrheal patients with the symptoms including mucus feces, fever, white blood cell (WBC) and red blood cell (RBC) in feces were higher than the patients without these symptoms (P>0.05). The 9 of 28 Yersiniosis cases by etiology diagnosis were clinical diagnosed as bacillary dysentery. Conclusion: The infants and young children under 5-year old were the main population of Yersiniosis adolescent patients under 14-year old. The typical symptoms characterized with mucus stool, fever, WBC and RBC by routine microscopic examination. The preliminary clinical diagnosis of Yersiniosis is easily confused with bacterial dysentery.


Assuntos
Yersiniose/epidemiologia , Yersinia , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Diarreia , Disenteria , Humanos , Lactente , Yersinia enterocolitica
12.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(11): 1147-1151, 2019 Nov 06.
Artigo em Zh | MEDLINE | ID: mdl-31683403

RESUMO

Objective: To examine the association of pre-pregnancy body mass and weight gain during pregnancy with macrosomia. Methods: From January 2015 to December 2015, a total of 20 477 pregnant women were recruited by probabilistic proportional scale sampling with simple randomization in Sichuan, Yunnan and Guizhou Provinces. Basic information of pregnant women, weight gain during pregnancy and weight of newborn were collected. A multiple logistic regression model was used to assess the association between the pre-pregnancy body mass and gestational weight gain indicators with macrosomia. Results: 20 321 mother-infant were included in the final analysis. 20 321 pregnant women were (30.09±4.10) years old and delivered at (39.20±1.29) weeks, among which 12 341 (60.73%) cases were cesarean delivery. The birth weight of 20 321 infants were (3 292.26±431.67) grams, and 970 (4.77%) were macrosomia. The multiple logistic regression model showed that after adjusting for the age of women, compared to the normal weight group in the pre-pregnancy, the overweight and obesity group elevated the risk of macrosomia, with OR (95%CI) about 1.99 (95%CI: 1.69-2.35) and 4.05 (95%CI: 3.05-5.39), respectively. After adjusting for the age, the pre-pregnancy BMI, delivery weeks, delivery mode and infant's gender, compared to the weight-gain appropriate group, higher weight gain rate in the mid-pregnancy and excessive total gestational weight gain elevated the risk of macrosomia, with OR (95%CI) about 1.99 (95%CI: 1.66-2.39) and 1.80 (95%CI: 1.55-2.08), respectively. Conclusion: The overweight before pregnancy, obesity before pregnancy, the rate of weight gain in the second trimester and the high total weight gain during pregnancy could increase the risk of macrosomia.


Assuntos
Índice de Massa Corporal , Macrossomia Fetal/epidemiologia , Sobrepeso/epidemiologia , Aumento de Peso , Adulto , Peso ao Nascer , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Obesidade/epidemiologia , Gravidez , Complicações na Gravidez/epidemiologia , Resultado da Gravidez , Segundo Trimestre da Gravidez , Fatores de Risco
13.
Zhonghua Yu Fang Yi Xue Za Zhi ; 52(6): 653-660, 2018 Jun 06.
Artigo em Zh | MEDLINE | ID: mdl-29886689

RESUMO

Objective: In this study, we analyze the regulation mechanisms of the expression of ampD in AmpC ß-lactamase and the regulation mechanism of ß-N-acetylglucosaminidase (NagZ) in Yersinia enterocolitica. Methods: We construct the mutation strains of Yersinia enterocolitica AmpD (AmpD1-3) gene (ampD1-3), Low-Molecular-Mass Penicillin-Binding Proteins (LMM PBPs) gene (pbp4, pbp5a, pbp5b, pbp7), NagZ gene (nagZ), and ampR gene by deleting and complementing genes, and induce them by cefoxitin. We determined the activity of AmpC ß-lactamase activity (U) of mutant strains (basal level and induce level) by using cephalothiophene hydrolysis method, the promoter activity of AmpC ß-lactamase ((relative light unit (RLU)) was detected by the luxCDABEreporter system, and the activity of ß-N-acetylglucosaminidase (nmol/L) was determined by by using 4-nitrophenyl N-acetyl-ß-D-glucosaminide as the chromogenic substrate. Results: AmpD1 (Basal level: (3.29±1.58) U; Induced level: (4.08±1.75) U) was the most potent one. The YEΔ5b, YEΔ4Δ5b, YEΔ5aΔ5b and YEΔ5bΔ7 of ampC promoter activity increase significantly, whichYEΔ4Δ5b is the highest one (Basal level: (106 903.16±61 910.61) RLU; Induced level: (205 427.45±45 352.17) RLU). The YEΔ4Δ5bΔ7 of ampC promoter activity is the highest among triple mutant strain (Basal level: (304 108.04±99 274.53) RLU; Induced level: (531 440.21±68 891.02) RLU). Quadruple deletion strain YEΔ4Δ5aΔ5bΔ7 have the highest ampC promoter activity (Basal level: (1 013 810.99±260 955.96) RLU; Induced level: (1 230 214.59±205 526.79) RLU). After the deletion of nagZ gene, there is no significant change in ß-lactamase activity of YEΔD1D2D3ΔZ, while ß-lactamase activity of YEΔ4Δ5aΔ5bΔ7ΔZ shows a significant decrease (Basal level: (0.30±0.20) U; Induced level: (0.29±0.21) U), which basically drops to the wild strain level. Conclusion: This is the first report of ampC multi-step upregulation mechanism driven by three AmpD homologues in Yersinia enterocolitica. The AmpC regulation mode with the function of single PBP4, PBP5a or PBP7 is relatively low, which work in coordination with PBP5b. Yersinia enterocolitica have both NagZ-depend and NagZ-independent mechanisms for ß-lactamase expression.


Assuntos
Acetilglucosaminidase/metabolismo , Proteínas de Bactérias/metabolismo , N-Acetil-Muramil-L-Alanina Amidase/metabolismo , Yersinia enterocolitica/metabolismo , beta-Lactamases/metabolismo , Humanos
14.
Andrologia ; 49(10)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28224651

RESUMO

Previous research has shown benefits of dietary fish oil supplementation on semen quality of boars. However, little is known about how antioxidant protects lipid peroxidation on spermatozoa from n-3 polyunsaturated fatty acid (PUFA) addition. This study evaluated the effect of oregano essential oil (OEO) supplementation on semen antioxidant status and semen quality in boars fed a diet enriched with fish oil. Thirty-four mature boars of proven fertility, received daily 2.5 kg basal diet top-dressed with 45 g soybean oil and 15 g fish oil to meet the n-3 PUFA requirement of spermatozoa, randomly allocated to one of four groups supplemented with 100 mg α-tocopheryl acetate kg-1 (control), or 250 or 500 or 750 mg OEO kg-1 for 16 weeks. Semen was collected at weeks 0, 8, 12 and 16 for measurements of sperm production, motion characteristics, sperm α-tocopherol content, antioxidant enzyme activities, reactive oxygen species (ROS), DNA damage (8-hydroxydeoxyguanosine, 8-OHdG), lipoperoxidation (malondialdehyde, MDA) and seminal total antioxidant capacity (TAC). Sperm production and motion characteristics were similar (p > .05) among groups throughout the experimental week 16, but increased (p < .01) with experimental week. Although higher α-tocopherol content and superoxide dismutase (SOD) activities were in OEO group spermatozoa, feeding diet with 500 mg/kg OEO resulted in elevation in seminal TAC, decrease in sperm ROS, MDA and 8-OHdG than control group (p < .05). Overall, these results support the view that oregano essential oil has a positive effect on antioxidant capacity in boar when used fish oil.


Assuntos
Suplementos Nutricionais , Óleos de Peixe/administração & dosagem , Óleos Voláteis/administração & dosagem , Origanum , Estresse Oxidativo/efeitos dos fármacos , Sêmen/efeitos dos fármacos , Animais , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sêmen/metabolismo , Análise do Sêmen , Motilidade dos Espermatozoides/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Suínos
15.
World J Microbiol Biotechnol ; 33(2): 33, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28074411

RESUMO

The filamentous Cyanobacterium Arthrospira is commercially produced and is a functional, high-value, health food. We identified 5 low temperature and low light intensity tolerant strains of Arthrospira sp. (GMPA1, GMPA7, GMPB1, GMPC1, and GMPC3) using ethyl methanesulfonate mutagenesis and low temperature screening. The 5 Arthrospira strains grew rapidly below 14 °C, 43.75 µmol photons m-2 s-1 and performed breed conservation at 2.5 °C, 8.75 µmol photons m-2 s-1. We used morphological identification and molecular genetic analysis to identify GMPA1, GMPA7, GMPB1 and GMPC1 as Arthrospira platensis, while GMPC3 was identified as Arthrospira maxima. Growth at different culture temperatures was determined at regular intervals using dry biomass. At 16 °C and 43.75 µmol photons m-2 s-1, the maximum dry biomass production and the mean dry biomass productivity of GMPA1, GMPB1, and GMPC1 were 2057 ± 80 mg l-1, 68.7 ± 2.5 mg l-1 day-1, 1839 ± 44 mg l-1, 60.6 ± 1.8 mg l-1 day-1, and 2113 ± 64 mg l-1, 77.7 ± 2.5 mg l-1 day-1 respectively. GMPB1 was chosen for additional low temperature tolerance studies and growth temperature preference. In winter, GMPB1 grew well at mean temperatures <10 °C, achieving 3258 mg dry biomass from a starting 68 mg. In summer, GMPB1 grew rapidly at mean temperatures more than 28 °C, achieving 1140 mg l-1 dry biomass from a starting 240 mg. Phytonutrient analysis of GMPB1 showed high levels of C-phycocyanin and carotenoids. Arthrospira metabolism relates to terpenoids, and the methyl-D-erythritol 4-phosphate pathway is the only terpenoid biosynthetic pathway in Cyanobacteria. The 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR) gene from GMPB1 was cloned and phylogenetic analysis showed that GMPB1 is closest to the Cyanobacterium Oscillatoria nigro-viridis PCC711. Low temperature tolerant Arthrospira strains could broaden the areas suitable for cultivation, extend the seasonal cultivation time, and lower production costs.


Assuntos
Biomassa , Oscillatoria/crescimento & desenvolvimento , Oscillatoria/metabolismo , Terpenos/metabolismo , Temperatura Baixa , Luz , Mutagênese , Oscillatoria/genética , Filogenia , Alinhamento de Sequência
16.
Zhonghua Yi Xue Za Zhi ; 97(17): 1333-1336, 2017 May 09.
Artigo em Zh | MEDLINE | ID: mdl-28482437

RESUMO

Objective: To determine the effects of QO-58 on pain behavior associated with monosodium iodoacetate (MIA)-induced OA. Methods: The OA model was established with an intra-articular injection of 3 mg/50 MIA through the right patellar ligament. Then the model rats were treated with 50 mg/kg QO-58 by intraperitoneal injection, and pain-related behaviors were assessed by single administration and multiple administrations of QO-58. Results: Single adminstration of QO-58 increased the mechanical threshold and prolonged the withdrawal latency of OA pain with the antinociceptive effect occurring at 6 h and 10 h. Compound QO-58 was administered intraperitoneally once a day from day 10 to 14. QO-58 significantly increased the mechanical threshold and prolonged the withdrawal latency of OA rats at 12 and 14 days. Conclusion: QO-58 showed antinociceptive effects for OA pain in the MIA model after pain development. QO-58 may be an alternative therapeutic treatment for OA.


Assuntos
Osteoartrite/tratamento farmacológico , Manejo da Dor , Analgésicos , Animais , Modelos Animais de Doenças , Osteoartrite/complicações , Dor/etiologia , Ratos , Ratos Sprague-Dawley
17.
Acta Endocrinol (Buchar) ; 13(4): 417-424, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-31149210

RESUMO

OBJECTIVE: To study the effect of diethylhexyl phthalate (DEHP) alone or in combination with genistein (GEN) on the reproductive system of offspring rats, focus on the induction of reproductive outcomes. METHOD: 180 Wistar rats were divided in 6 groups (30 animals per group): DEHP 250 mg/kg/day group, DEHP 1000 mg/kg/day group, DEHP 2500 mg/kg/day group treated with DEHP 2500 mg/kg/day, DEHP (2500 mg/kg) + GEN (50 mg/kg) group, DEHP (2500 mg/kg) + GEN (500 mg/kg) group and control group treated with the same quantity of corn oil. The differences in sperm quality and reproductive organs were observed. RESULTS: After DEHP administration we observed an increase in rat's abestrus, metaestrus and all estrus cycle (P < 0.05), a decrease in rat testicle's organ coefficient and relative energy of testis Sertoli cells and an increase in the early, late and total apoptotic rate of testicular Sertoli cells in a dose dependent manner (P < 0.05). When combine DEHP with GEN the sperm density, sperm quality, the cell activity rate and testis tissue's changes will decrease compared with the group that receive only DEHP in a dose dependent manner. CONCLUSION: DEHP exposure induces cryptorchidism in offspring rats and this is aggravated by adding GEN.

18.
Indoor Air ; 26(5): 806-19, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26547623

RESUMO

Gaspers installed in commercial airliner cabins are used to improve passengers' thermal comfort. To understand the impact of gasper airflow on the air quality in a cabin, this investigation measured the distributions of air velocity, air temperature, and gaseous contaminant concentration in five rows of the economy-class section of an MD-82 commercial aircraft. The gaseous contaminant was simulated using SF6 as a tracer gas with the source located at the mouth of a seated manikin close to the aisle. Two-fifths of the gaspers next to the aisle were turned on in the cabin, and each of them supplied air at a flow rate of 0.66 l/s. The airflow rate in the economy-class cabin was controlled at 10 l/s per passenger. Data obtained in a previous study of the cabin with all gaspers turned off were used for comparison. The results show that the jets from the gaspers had a substantial impact on the air velocity and contaminant transport in the cabin. The air velocity in the cabin was higher, and the air temperature slightly more uniform, when the gaspers were on than when they were off, but turning on the gaspers may not have improved the air quality.


Assuntos
Ar Condicionado/instrumentação , Movimentos do Ar , Poluição do Ar em Ambientes Fechados/análise , Aeronaves , Temperatura , Poluição do Ar , Humanos
19.
Genet Mol Res ; 14(4): 17927-33, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26782438

RESUMO

Dysregulated miR-125 observed in multiple cancer types has suggested that it is involved in malignant proliferation and invasion. However, the clinical significance of miR-125 in human breast cancer (BC) has not yet been fully elucidated. In the present study, the expression of miR-125a-5p/3p and miR-125b in 143 pairs of BC and normal adjacent tissues (NATs) was measured by real-time quantitative PCR, and the correlation between expression and clinicopathological features was explored. miR-125a-5p and miR-125b were significantly down-regulated in BC tissue samples compared with their matched NAT samples, while the difference in miR-125a-3p expression between BC tissues and NATs was not statistically significant. The expression level of miR-125a-5p was found to be significantly higher in younger patients (<35 years) than in older patients (≥35, P = 0.005). When the patients were divided into three groups according to age (<35, 36-48, and ≥48 years), a gradual reduction in miR-125a-5p expression was observed in BC tissue samples that correlated to increases in age (P = 0.009). There were no significant correlations between miR-125 expression and other clinicopathological features including tumor size, histological grade, hormone receptor status, Her-2 status, and lymph node metastasis. Taken together, these findings suggest that miR-125a-5p may play an important role in BC progression in an age-dependent manner, and that the down-regulation of miR-125a-5p and miR-125b may serve as independent predictors for breast cancer.


Assuntos
Biomarcadores Tumorais/biossíntese , Neoplasias da Mama/genética , MicroRNAs/biossíntese , Adulto , Fatores Etários , Idoso , Biomarcadores Tumorais/genética , Neoplasias da Mama/patologia , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , MicroRNAs/genética , Pessoa de Meia-Idade , Prognóstico , Receptor ErbB-2/genética
20.
Scand J Immunol ; 79(1): 12-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24354407

RESUMO

Berberine (BBR), an isoquinoline derivative alkaloid, has been extensively used in traditional Chinese medicine for the treatment of diarrhoea, rheumatic diseases, diabetes, etc. Recent studies have demonstrated new biological properties of BBR and suggested the possibility of BBR to be a therapeutic agent for some autoimmune diseases. To explore the effect of BBR on the development of experimental autoimmune neuritis (EAN), BBR was administered intragastrically daily to Lewis rats immunized with P0 peptide 180-199 in Freund's complete adjuvant. We found BBR treatment resulted in amelioration of EAN, accompanied by suppressed lymphocyte (in particular CD4(+) T cell) proliferation, downregulated Th1 (TNF-α) and Th2 (IL-10) cytokines and reduced anti-P0 peptide 180-199 IgG1 and IgG2a. In brief, BBR played a role in ameliorating EAN by suppressing both cellular and humoral immunity. Thus, our study suggests that BBR may be a potential therapeutic agent for the autoimmune disease in the peripheral nervous system, such as Guillain-Barré syndrome.


Assuntos
Berberina/farmacologia , Imunidade Celular/efeitos dos fármacos , Imunidade Humoral/efeitos dos fármacos , Neurite Autoimune Experimental/prevenção & controle , Sequência de Aminoácidos , Animais , Berberina/administração & dosagem , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Feminino , Citometria de Fluxo , Imunoglobulina G/metabolismo , Interleucina-10/metabolismo , Dados de Sequência Molecular , Proteína P0 da Mielina/química , Proteína P0 da Mielina/imunologia , Neurite Autoimune Experimental/imunologia , Fragmentos de Peptídeos/imunologia , Fitoterapia , Ratos , Ratos Endogâmicos Lew , Células Th1/efeitos dos fármacos , Células Th1/metabolismo , Células Th2/efeitos dos fármacos , Células Th2/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
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