RESUMEN
Cervical cancer (CC) is a gynecological malignant tumor worldwide. Astragaloside IV (AS-IV) has been found to exert antitumor effects on CC. In addition, M2-polarized macrophages, known as tumor-associated macrophages (TAMs), play an important role in promoting cancer cell growth and angiogenesis. Thus, we explored the association between the antitumor effect of AS-IV and macrophage polarization in CC. Flow cytometry, ELISA, and RTâqPCR assays were applied to detect the levels of CD163, IL-10, TGFß, and CD206 in M2 macrophages with or without AS-IV treatment. In addition, conditioned medium (CM) was collected from these M2 macrophages, and CC cells were then cultured in various CMs. Wound healing and transwell assays were used to assess the migratory ability of CC cells. In this study, we found that AS-IV significantly inhibited M2 polarization of macrophages, as shown by decreased CD163, IL-10, TGFß, and CD206 expression. In addition, compared with CM from M2 macrophages, CM from AS-IV-treated M2 macrophages notably inhibited angiogenesis, migration, and epithelial-mesenchymal transition (EMT) in CC cells. Furthermore, compared with CM from M2 macrophages, CM from AS-IV-treated M2 macrophages markedly reduced p-Smad2 and p-Smad3 protein expression in CC cells, and these changes were reversed by TGF-ß treatment. Collectively, suppression of M2-like polarization of macrophages by AS-IV could prevent the migration and EMT of CC cells by inactivating TGF-ß/Smad2/3 signaling. These findings might provide some theoretical support for exploring novel treatments for CC.
Asunto(s)
Transición Epitelial-Mesenquimal , Neoplasias del Cuello Uterino , Femenino , Humanos , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-10/farmacología , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/genética , Macrófagos/metabolismo , Línea Celular Tumoral , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Proteína Smad2/genética , Proteína Smad2/metabolismo , Proteína Smad2/farmacologíaRESUMEN
BACKGROUND: The mechanism underlying irritable bowel syndrome (IBS), a common disease with hyperalgesia, remains elusive. The spinal cholinergic system is involved in pain modulation, but its role in IBS is unknown. AIMS: To determine whether high-affinity choline transporter 1 (CHT1, a major determinant of the cholinergic signaling capacity), is implicated in spinal modulation of stress-induced hyperalgesia. METHODS: A rat IBS model was established by water avoidance stress (WAS). Visceral sensations were detected by abdominal withdrawal reflex (AWR) and visceromotor response (VMR) to colorectal distension (CRD). Abdominal mechanical sensitivity was determined by von Frey filaments (VFFs) test. RT-PCR, Western blot, and immunostaining were performed for spinal CHT1 expression. Spinal acetylcholine (ACh) was measured by ELISA; the influence of spinal CHT1 on hyperalgesia were evaluated by intrathecal administration of MKC-231 (a choline uptake enhancer) and hemicholinium-3 (HC-3, a specific inhibitor of CHT1). Minocycline treatment was used to explore the role of spinal microglia in hyperalgesia. RESULTS: After 10 days of WAS, AWR scores and VMR magnitude to CRD, and the number of withdrawal events in VFF test were increased. Double-labeling showed that CHT1 in the dorsal horn was expressed in most of the neurons and almost all the microglia. The CHT1 expression and ACh levels in the spinal cord and the density of CHT1-positive cell in the spinal dorsal horn were enhanced in WAS-exposed rats. HC-3 enhanced pain responses in WAS rats; MKC-231 alleviated pain in WAS rats by upregulating CHT1 expression and increasing ACh production in the spinal cord. Furthermore, microglial activation in the spinal dorsal horn promoted the stress-induced hyperalgesia, and MKC-231 achieved analgesic effects by inhibiting the spinal microglial activation. CONCLUSIONS: CHT1 exerts antinociceptive effects in spinal modulation of chronic stress-induced hyperalgesia by increasing ACh synthesis and suppressing microglial activation. MKC-231 has potential for treating disorders accompanied by hyperalgesia.
Asunto(s)
Hiperalgesia , Síndrome del Colon Irritable , Ratas , Animales , Hiperalgesia/inducido químicamente , Ratas Sprague-Dawley , Síndrome del Colon Irritable/metabolismo , Médula Espinal/metabolismo , Acetilcolina/farmacología , Dolor , Colinérgicos/efectos adversos , Colinérgicos/metabolismoRESUMEN
BACKGROUND: Hydrogen sulfide (H2 S), an important endogenous gasotransmitter, is involved in the modulation of gastrointestinal motility, but whether it mediates the intestinal dysmotility in irritable bowel syndrome (IBS) is not known. This study explored the significance of cystathionine-ß-synthase (CBS)/H2 S signaling in stress-induced colonic dysmotility. METHODS: A rat model of IBS was established using chronic water avoidance stress (WAS). Colonic pathological alterations were detected histologically. Intestinal motility was determined by intestinal transit time (ITT) and fecal water content (FWC). Visceral sensitivity was assessed using the visceromotor response (VMR) to colorectal distension (CRD). Real-time PCR, Western blotting, and immunostaining were performed to identify the expression of CBS in the colon. The contractions of distal colon were studied in an organ bath system and H2 S content was measured by ELISA. The effects of SAM, a selective CBS activator, on colonic dysmotility were examined. MEK1 was tested as a potential upstream effector of CBS/H2 S loss. KEY RESULTS: After 10 days of WAS, the ITT was decreased and FWC was increased, and the VMR magnitude in response to CRD was enhanced. The colonic CBS expression and H2 S levels were significantly declined in WAS-exposed rats, and the density of CBS-positive enteric neurons in the myenteric plexus in WAS-treated rats was lower than that in controls. SAM treatment relieved WAS-induced colonic hypermotility via increased H2 S production. AZD6244, a selective inhibitor of MEK1, partially reversed CBS downregulation and colonic hypermotility in WAS-treated rats. CONCLUSIONS & INFERENCES: Decreased CBS/H2 S signaling through increased MEK1 signaling might be important in the pathogenesis of chronic stress-induced colonic hypermotility. SAM could be administered for disorders associated with intestinal hypermotility.
Asunto(s)
Sulfuro de Hidrógeno , Síndrome del Colon Irritable , Ratas , Animales , Sulfuro de Hidrógeno/metabolismo , Síndrome del Colon Irritable/metabolismo , Cistationina/metabolismo , Cistationina/farmacología , Cistationina betasintasa/metabolismo , Colon/metabolismo , Agua , DeshidrataciónRESUMEN
BACKGROUND: White light endoscopy is a pivotal first-line tool for the detection of gastric neoplasms. However, gastric neoplasms can be missed during upper gastrointestinal endoscopy due to the subtle nature of these lesions and varying skill among endoscopists. Here, we aimed to evaluate the effect of an artificial intelligence (AI) system designed to detect focal lesions and diagnose gastric neoplasms on reducing the miss rate of gastric neoplasms in clinical practice. METHODS: This single-centre, randomised controlled, tandem trial was done at Renmin Hospital of Wuhan University, China. We recruited consecutive patients (≥18 years old) undergoing routine upper gastrointestinal endoscopy for screening, surveillance, or investigation of symptoms. Same-day tandem upper gastrointestinal endoscopy was done where patients first underwent either AI-assisted (AI-first) or routine (routine-first) white light endoscopy, followed immediately by the other procedure, with targeted biopsies for all detected lesions taken at the end of the second examination. Patients were randomly assigned (1:1) to the AI-first or routine-first group using a computer-generated random numerical series and block randomisation (block size of four). Endoscopists were not blinded to randomisation status, whereas patients and pathologists were. The primary endpoint was the miss rate of gastric neoplasms and the analysis was done per protocol. This trial is registered with the Chinese Clinical Trial Registry, ChiCTR2000034453, and has been completed. FINDINGS: Between July 6, 2020, and Dec 11, 2020, 907 patients were randomly assigned to the AI-first group and 905 to the routine-first group. The gastric neoplasm miss rate was significantly lower in the AI-first group than in the routine-first group (6·1%, 95% CI 1·6-17·9 [3/49] vs 27·3%, 15·5-43·0 [12/44]; relative risk 0·224, 95% CI 0·068-0·744; p=0·015). The only reported adverse event was bleeding from a target lesion after biopsy. INTERPRETATION: The use of an AI system during upper gastrointestinal endoscopy significantly reduced the gastric neoplasm miss rate. AI-assisted endoscopy has the potential to improve the yield of gastric neoplasms by endoscopists. FUNDING: The Project of Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision and the Hubei Province Major Science and Technology Innovation Project.
Asunto(s)
Inteligencia Artificial , Aprendizaje Profundo , Endoscopía del Sistema Digestivo/métodos , Tamizaje Masivo/métodos , Neoplasias Gástricas/diagnóstico , Adulto , China/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias Gástricas/epidemiologíaRESUMEN
INTRODUCTION: Gastrointestinal endoscopic quality is operator-dependent. To ensure the endoscopy quality, we constructed an endoscopic audit and feedback system named Endo.Adm and evaluated its effect in a form of pretest and posttest trial. METHODS: Endo.Adm system was developed using Python and Deep Convolutional Neural Ne2rk models. Sixteen endoscopists were recruited from Renmin Hospital of Wuhan University and were randomly assigned to undergo feedback of Endo.Adm or not (8 for the feedback group and 8 for the control group). The feedback group received weekly quality report cards which were automatically generated by Endo.Adm. We then compared the adenoma detection rate (ADR) and gastric precancerous conditions detection rate between baseline and postintervention phase for endoscopists in each group to evaluate the impact of Endo.Adm feedback. In total, 1,191 colonoscopies and 3,515 gastroscopies were included for analysis. RESULTS: ADR was increased after Endo.Adm feedback (10.8%-20.3%, P < 0.01, Asunto(s)
Adenoma/diagnóstico por imagen
, Competencia Clínica
, Colonoscopía/normas
, Aprendizaje Profundo
, Indicadores de Calidad de la Atención de Salud/estadística & datos numéricos
, Adenoma/epidemiología
, Adulto
, China
, Detección Precoz del Cáncer
, Retroalimentación
, Femenino
, Humanos
, Masculino
, Persona de Mediana Edad
, Mejoramiento de la Calidad
, Factores de Riesgo
RESUMEN
Optical loss is generally perceived to be an adverse effect in integrated optics. Herein, in contrast, we propose a mechanism to harness the loss in a coupled ${\rm {high-}}{\! Q}$ resonators system to realize on-chip electromagnetically induced transparency (EIT). The increasing loss of one of the coupled resonators results in a difference in ${Q}$ factor, leading to EIT generation. This optical loss-induced EIT is studied analytically using the coupled-mode theory and demonstrated experimentally in chalcogenide coupled microring resonators. By taking advantage of the chalcogenide phase change materials that feature exceptional optical property contrasts, we further demonstrate the loss-induced mechanism to realize fast and nonvolatile responses between the EIT state and the critical coupling state in a monolithically integrated chip. Our results provide a new perspective to harvest the negative loss effect of coupled resonators for tunable photonic devices, which might shed new light on the design ideology for on-chip slow-light optical components.
RESUMEN
BACKGROUND: Previous studies showed the incidence, persistence and clearance of cervical human papillomavirus (HPV) among women varies from regions. There is no study on dynamic changes of HPV infection among women in Guangdong. METHODS: It is a retrospective cohort study that included gynecological outpatients aged ≥15 years and retested for HPV within 24 months in Guangdong Women and Children Hospital to estimate HPV incidence, persistence and clearance. Outcomes were estimated through the proportion of HPV incidence, persistence and clearance in HPV-negative or HPV-positive women. Moreover, we examined HPV incidence, persistence and clearance among women who retested in four calendar periods: 0-6, 6-12, 12-18, 18-24 months after the first test. RESULTS: 33,328 gynecological outpatients were included in our study. Incidence rates of any HPV, high-risk (HR) HPV and low-risk (LR) HPV were 10.58%, 8.68% and 4.83%. The most common incident HR HPV were HPV52 (2.69%), HPV16 (1.23%) and HPV58 (1.23%). Persistence rates of any HPV, HR HPV and LR HPV were 47.55%, 42.77% and 33.88%. HPV52 (42.33%), HPV58 (40.74%) and HPV68 (32.36%) were commonly found persistent types. And clearance rates of any HPV, HR HPV and LR HPV were 52.44%, 57.23% and 66.12%.The lowest clearance rates were observed for HPV52 (57.67%), HPV68 (67.64%) and HPV39 (68.56%). HPV incidence and persistence were higher among women aged 15-19 years and ≥55 years. HPV incidence and persistence were found higher among women who retested within 6 months than others in other periods. CONCLUSIONS: HPV52, 58, 68, and 39 were the more likely to cause incident and persistent infection, and less likely to be cleared among women in Guangdong. HPV incidence and persistent infection were higher among women aged both younger and older women compared to middle aged women. HPV retesting period may impact the detection of HPV incidence, persistence and clearance.
Asunto(s)
Alphapapillomavirus , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Adolescente , Adulto , Anciano , Niño , China/epidemiología , Femenino , Genotipo , Humanos , Incidencia , Persona de Mediana Edad , Papillomaviridae , Infecciones por Papillomavirus/epidemiología , Estudios Retrospectivos , Adulto JovenRESUMEN
BACKGROUND: As the fourth most common cancer among women worldwide, cervical cancer lead to 311,000 deaths in 2018. Although the treatments have been developed, the survival rate of cervical cancer remains unsatisfactory. In this study, we aimed to identify differentially expressed lncRNAs (DEIncRNAs) between cervical cancer and adjacent normal tissues using bioinformatics analysis, and further to investigate the biological function of the DEIncRNAs in vitro and in vivo. METHODS: The expression profiles from two microarray datasets (GSE6791 and GSE63514) were downloaded from GEO for analysis of DEIncRNAs between cervical cancer and adjacent normal cervical tissues. Among all DEIncRNAs, MIR155HG upregulation was identified and selected for further investigation. The effect of MIR155HG knockdown on proliferation, apoptosis and invasion in SiHa and Hela cells were evaluated. In addition, Western blot, RNA immunoprecipitation (RIP) and cell cycle assays were performed to determine the binding target of MIR155HG. Furthermore, the effect of MIR155HG knockdown on tumor growth in vivo was investigated. RESULTS: The level of MIR155HG was found to be significantly upregulated in cervical cancer tissue compared with adjacent cervical tissue. Knockdown of MIR155HG notably inhibited the proliferation of SiHa and Hela cells by inducing apoptosis. In addition, MIR155HG knockdown decreased cell invasion. Moreover, tumor growth in xenograft was significantly inhibited by MIR155HG knockdown in vivo. Additionally, SRSF1 was identified as the binding protein of MIR155HG. CONCLUSION: Our findings demonstrated that MIR155HG knockdown inhibited the progression of cervical cancer by binding SRSF1, inspiring the usage of MIR155HG as a potential novel therapy target for the treatment of cervical cancer.
RESUMEN
Our study aimed to analyze genotype-specific, age-specific prevalence, and year-on-year trend of cervical human papillomavirus (HPV) detection among women in Guangdong, China 2008 to 2017. A total of 199 963 women attending the gynecological department and 11 999 women attending the medical examination center at Guangdong Women and Children Hospital were included. Prevalent HPV detection significantly differed between these two groups of women (20.16% vs 17.25%; P < .001). HPV genotypes of these two populations have a large overlap, with HPV52, 16, 58, CP8304, and 53 being the dominant subtypes among gynecological outpatients and HPV52, CP8304, 58, 53, and 16 among women receiving physical examinations. The distribution of prevalent HPV detection showed a bimodal pattern across age groups among these two populations. However, prevalent HPV detection among these two populations exhibited different trends from 2008 to 2017. Our study demonstrated that prevalent HPV detection among women in Guangdong is associated with age and different from that among women from other regions of China. Our study may provide valuable data to inform cervical cancer screening and HPV vaccination programs for women in this province.
Asunto(s)
Papillomaviridae/genética , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/inmunología , Adolescente , Adulto , Envejecimiento , Cuello del Útero/virología , ADN Viral/genética , Femenino , Genotipo , Humanos , Persona de Mediana Edad , Papillomaviridae/patogenicidad , Infecciones por Papillomavirus/virología , Vacunas contra Papillomavirus/administración & dosificación , Adulto JovenRESUMEN
BACKGROUND: To explore the diagnostic value of FAM19A4 methylation in high-risk human papilloma virus (hrHPV)-positive cervical samples from Chinese women for estimating cervical cancer or its precancerous lesions. METHODS: Cervical samples from 215 women infected with high-risk HPV were collected by smear testing. We purposely chose 61 patients with cervical cancer, 57 with high-grade squamous intraepithelial lesions (HSIL), 31 with low-grade squamous intraepithelial lesions (LSIL), and 66 without cervical intraepithelial neoplasia (CIN) after histological confirmation. Taqman probe-based quantitative PCR (qPCR) was utilized to detect the methylation status of FAM19A4 in the cervical samples and further evaluate the use of this gene in the diagnosis of cervical cancer. RESULTS: (1) An increasing level of FAM19A4 methylation was detected with increasing progression of cervical lesions, with methylation rates of 10.61%(7/66), 35.48%(11/31), 56.14%(32/57) and 93.44%(57/61) in no CIN, LSIL, HSIL and cervical carcinoma samples respectively. (2) In all hrHPV-positive samples, the levels of FAM19A4 methylation in HPV16/18 groups were higher than that in 12 other hrHPV groups (P < 0.05), but there was no significant difference between two groups after grouping cervical lesions into cervical cancer, HSIL, LSIL and no CIN groups (P>0.05). (3)There were no significant differences of FAM19A4 methylation in different clinicopathological parameters of cervical cancer. (4) Though the sensitivity of FAM19A4 methylation test was inferior to that of cytology and FAM19A4 combining with HPV16/18 genotyping, but showed the best specificity with 81.44% both for detection HSIL alone and ≥ HSIL, with favorable youden index (YI) and area under curve (AUC). CONCLUSION: FAM19A4 is a specific biomarker of cancerous lesions of the cervix. FAM19A4 methylation analysis may serve as an auxiliary screening method for diagnosis of cervical (pre)cancer. However, in consideration of the limitations of this retrospective study, prospective population-based studies are necessary for further confirmation of the diagnostic value of FAM19A4 methylation for detection of cervical (pre)cancer in Chinese women.
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Pueblo Asiatico/genética , Cuello del Útero/virología , Citocinas/genética , Metilación de ADN/genética , Infecciones por Papillomavirus/genética , Neoplasias del Cuello Uterino/genética , Femenino , Genotipo , Humanos , Persona de Mediana Edad , Papillomaviridae/patogenicidad , Infecciones por Papillomavirus/virología , Estudios Retrospectivos , Riesgo , Neoplasias del Cuello Uterino/virología , Frotis Vaginal/métodosRESUMEN
Copy number variations (CNVs) have attracted increasing evidences to represent their roles as cancer susceptibility regulators. However, little is known about the role of CNV in epithelia ovarian cancer (EOC). Recently, the CNV-67048 of WW domain-containing oxidoreductase (WWOX) was reported to alter cancer risks. Considering that WWOX also plays a role in EOC, we hypothesized that the CNV-67048 was associated with EOC risk. In a case-control study of 549 EOC patients and 571 age (±5 years) matched cancer-free controls, we found that the low copy number of CNV-67048 (1-copy and 0-copy) conferred a significantly increased risk of EOC (OR = 1.346, 95% CI = 1.037-1.747) and it determined the risk by means of copy number-dependent dosage effect (P = 0.009). Data from TCGA also confirmed the abovementioned association as the frequency of low copies in EOC group was 3.68 times more than that in healthy group (P = 0.023). The CNV also negatively interacted with oral contraceptive use on EOC risk (P = 0.042). Functional analyses further showed a lower mRNA level of WWOX in tissues with the 0-copy or 1-copy than that in those with the 2-copy (P = 0.045). Our data suggested the CNV-67048 to be a risk factor of EOC in Chinese women.
Asunto(s)
Anticonceptivos Orales/efectos adversos , Variaciones en el Número de Copia de ADN/genética , Neoplasias Glandulares y Epiteliales/genética , Neoplasias Ováricas/genética , Oxidorreductasas/genética , Proteínas Supresoras de Tumor/genética , Anciano , Carcinoma Epitelial de Ovario , Femenino , Estudios de Asociación Genética , Humanos , Persona de Mediana Edad , Neoplasias Glandulares y Epiteliales/etiología , Neoplasias Glandulares y Epiteliales/patología , Neoplasias Ováricas/etiología , Neoplasias Ováricas/patología , Factores de Riesgo , Oxidorreductasa que Contiene Dominios WWRESUMEN
BACKGROUND: The Qinghai-Tibet Plateau (QTP) of China is an extensive pastoral and semi-pastoral area, and because of poverty and bad hygiene conditions, Brucella is highly prevalent in this region. In order to adequately prevent this disease in the QTP region it is important to determine the identity of Brucella species that caused the infection. METHODS: A total of 65 Brucella isolates were obtained from human, livestock and wild animals in Qinghai, a Chinese province in east of the QTP. Two molecular typing methods, MLVA (multi-locus variable-number tandem-repeat analysis) and MLST (multi locus sequence typing) were used to identify the species and genotypes of these isolates. FINDINGS: Both MLVA and MLST typing methods classified the 65 isolates into three species, B. melitensis, B. abortus and B. suis, which included 60, 4 and 1 isolates respectively. The MLVA method uniquely detected 34 (Bm01 ~ Bm34), 3 (Ba01 ~ Ba03), and 1 (Bs01) MLVA-16 genotypes for B. melitensis, B. abortus and B. suis, respectively. However, none of these genotypes exactly matched any of the genotypes in the Brucella2012 MLVA database. The MLST method identified five known ST types: ST7 and ST8 (B. melitensis), ST2 and ST5 (B. abortus), and ST14 (B. suis). We also detected a strain with a mutant type (3-2-3-2-?-5-3-8-2) of ST8 (3-2-3-2-1-5-3-8-2). Extensive genotype-sharing events could be observed among isolates from different host species. CONCLUSIONS: There were at least three Brucella (B. melitensis, B. abortus and B. suis) species in Qinghai, of which B. melitensis was the predominant species in the area examined. The Brucella population in Qinghai was very different from other regions of the world, possibly owing to the unique geographical characteristics such as extremely high altitude in QTP. There were extensive genotype-sharing events between isolates obtained from humans and other animals. Yaks, sheep and blue sheep were important zoonotic reservoirs of brucellosis causing species found in humans.
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Brucella/aislamiento & purificación , Brucelosis/microbiología , Brucelosis/veterinaria , Tipificación de Secuencias Multilocus/métodos , Animales , Brucella/clasificación , Brucella/genética , Bovinos/microbiología , China , Genotipo , Humanos , Repeticiones de Minisatélite , Filogenia , Rumiantes/microbiología , Ovinos/microbiologíaRESUMEN
In China, brucellosis is an endemic disease and the main sources of brucellosis in animals and humans are infected sheep, cattle and swine. Brucella melitensis (biovars 1 and 3) is the predominant species, associated with sporadic cases and outbreak in humans. Isolates of B. abortus, primarily biovars 1 and 3, and B. suis biovars 1 and 3 are also associated with sporadic human brucellosis. In this study, the genetic profiles of B. melitensis and B. abortus isolates from humans and animals were analyzed and compared by multi-locus variable-number tandem-repeat analysis (MLVA). Among the B. melitensis isolates, the majority (74/82) belonged to MLVA8 genotype 42, clustering in the 'East Mediterranean' group. Two B. melitensis biovar 1 genotype 47 isolates, belonging to the 'Americas' group, were recovered; both were from the Himalayan blue sheep (Pseudois nayaur, a wild animal). The majority of B. abortus isolates (51/70) were biovar 3, genotype 36. Ten B. suis biovar 1 field isolates, including seven outbreak isolates recovered from a cattle farm in Inner Mongolia, were genetically indistinguishable from the vaccine strain S2, based on MLVA cluster analysis. MLVA analysis provided important information for epidemiological trace-back. To the best of our knowledge, this is the first report to associate Brucella cross-infection with the vaccine strain S2 based on molecular comparison of recovered isolates to the vaccine strain. MLVA typing could be an essential assay to improve brucellosis surveillance and control programs.