Establishment of extensively drug-resistant Pseudomonas aeruginosa pneumonia model in rat

Objective:To establish extensively drug-resistant Pseudomonas aeruginosa(XDR-PA)infection-induced pneumonia model in rats.Methods:Twenty-four male SD rats were randomly divided into blank group,low bacterial group,medium bacterial group,and high bacterial group.The low,medium and high bacterial groups were given intratracheal instillation of 0.1 mL of bacterial suspension(bacterial concentration in turn is 7.5×10^(9),3×10^(10),6×10^(10)CFU/mL),while the blank group were given the same volume of sterile normal saline.After modeling,the general conditions of rats in each group were observed,including mental state,hair,respiration,activity,eating,weight,and the survival curve was drawn.The pathological characteristics of lung tissue and the infiltration of inflammatory cells were observed.Pathogenic identification of each group was carried out by bacterial culture of lung tissue homogenate.Results:The general state of the blank group was normal,and the rats in other groups showed signs of mental depression,bristling,shortness of breath,even oral and nasal bleeding,decreased food intake and activity,and significant weight loss,and different degrees of death within 48 hours,the difference was statistically significant(P<0.05).Pathological results showed that the alveolar structure of rats in the blank group was complete,and the alveolar space was clear without exudation.The lung tissue of the low and medium bacterial groups showed obvious inflammatory cell infiltration,alveolar structure destruction,alveolar septum thickening,interstitial edema,but the pathological damage of the medium group was more severe,with a mortality rate of up to 50%,and the mortality rate of the low bacterial group was 17%.In the high bacterial group,red blood cells,inflammatory cells and a large amount of fibrin-like exudation can be seen in the alveolar space,which has the pathological characteristics of acute respiratory failure,and the mortality rate is as high as 67%.The results of bacterial culture of lung tissue homogenate showed that the blank group had no bacterial colonies,while PA colony growth can be seen in low,medium and high bacterial groups.Conclusion:9 Intratracheal instillation of low bacterial count(0.1 mL of 7.5×10^(9) CFU/mL)XDR-PA bacterial suspension can successfully construct a rat pneumonia model of XDR-PA infection.

Extensively drug-resistant bacteria are an independent predictive factor of mortality in 130 patients with spontaneous bacterial peritonitis or spontaneous bacteremia

AIM: To evaluate the epidemiology and outcomes of culture-positive spontaneous bacterial peritonitis (SBP) and spontaneous bacteremia (SB) in decompensated cirrhosis.METHODS: We prospectively collected clinical, laboratory characteristics, type of administered antibiotic, susceptibility and resistance of bacteria to antibiotics in one hundred thirty cases (68.5% males) with positive ascitic fluid and/or blood cultures during the period from January 1, 2012 to May 30, 2014. All patients with SBP had polymorphonuclear cell count in ascitic fluid > 250/mm3. In patients with SB a thorough study did not reveal any other cause of bacteremia. The patients were followed-up for a 30-d period following diagnosis of the infection. The final outcome of the patients was recorded in the end of follow-up and comparison among 3 groups of patients according to the pattern of drug resistance was performed.RESULTS: Gram-positive-cocci (GPC) were found in half of the cases. The most prevalent organisms in a descending order were Escherichia coli (33), Enterococcus spp (30), Streptococcus spp (25), Klebsiella pneumonia (16), S. aureus (8), Pseudomanas aeruginosa (5), other Gram-negative-bacteria (GNB) (11) and anaerobes (2). Overall, 20.8% of isolates were multidrug-resistant (MDR) and 10% extensively drug-resistant (XDR). Health-care-associated (HCA) and/or nosocomial infections were present in 100% of MDR/XDR and in 65.5% of non-DR cases. Meropenem was the empirically prescribed antibiotic in HCA/nosocomial infections showing a drug-resistance rate of 30.7% while third generation cephalosporins of 43.8%. Meropenem was ineffective on both XDR bacteria and Enterococcus faecium (E. faecium). All but one XDR were susceptible to colistin while all GPC (including E. faecium) and the 86% of GNB to tigecycline. Overall 30-d mortality was 37.7% (69.2% for XDR and 34.2% for the rest of the patients) (log rank, P = 0.015). In multivariate analysis, factors adversely affecting outcome included XDR infection (HR = 2.263, 95%CI: 1.005-5.095, P = 0.049), creatinine (HR = 1.125, 95%CI: 1.024-1.236, P = 0.015) and INR (HR =1.553, 95%CI: 1.106-2.180, P = 0.011).CONCLUSION: XDR bacteria are an independent life-threatening factor in SBP/SB. Strategies aiming at restricting antibiotic overuse and rapid identification of the responsible bacteria could help improve survival.

Prolonged use of bedaquiline in two patients with pulmonary extensively drug-resistant tuberculosis: Two case reports

BACKGROUND Bedaquiline is among the prioritized drugs recommended by the World Health Organization for the treatment of extensively drug-resistant tuberculosis(XDRTB).Many patients have not achieved better clinical improvement after bedaquiline is stopped at 24 wk.However,there is no recommendation or guideline on bedaquiline administration beyond 24 wk,which is an important consideration when balancing the benefit of prognosis for XDR-TB against the uncertain safety concerning the newer antibiotics.CASE SUMMARY This paper reported 2 patients with XDR-TB(a female of 58 years of age and a female of 18 years of age)who received bedaquiline for 36 wk,as local experience to be shared.The 2 cases had negative cultures after 24 wk of treatment,but lung imaging was still positive.After discussion among experts,the consensus was made to bedaquiline prolongation by another 12 wk.The 36-wk prolonged use of bedaquiline in both cases achieved a favorable response without increasing the risk of cardiac events or new safety signals.CONCLUSION Longer regimen,including 36-wk bedaquiline treatment,might be an option for patients with XDR-TB.More studies are needed to explore the effectiveness and safety of prolonged use of bedaquiline for 36 wk vs standard 24 wk in the treatment of multidrug-resistant/XDR-TB or to investigate further the biomarkers and criteria indicative for extension of bedaquline to facilitate clinical use of thisnovel drug.

Successful treatment of pyogenic ventriculitis caused by extensively drug-resistant Acinetobacter baumannii with multi-route tigecycline: A case report

BACKGROUND Pyogenic ventriculitis caused by extensively drug-resistant Acinetobacter baumannii(A.baumannii)is one of the most severe complications associated with craniotomy.However,limited therapeutic options exist for the treatment of A.baumannii ventriculitis due to the poor penetration rate of most antibiotics through the blood-brain barrier.CASE SUMMARY A 68-year-old male patient with severe traumatic brain injury developed pyogenic ventriculitis on postoperative day 24 caused by extensively drug-resistant A.baumannii susceptible to tigecycline only.Successful treatment was accomplished through multi-route administration of tigecycline,including intravenous combined with continuous ventricular irrigation plus intraventricular administration.The pus was cleared on the 3rd day post-irrigation,and cerebrospinal fluid cultures were negative after 12 d.CONCLUSION Our findings suggest that multi-route administration of tigecycline can be a therapeutic option against pyogenic ventriculitis caused by extensively drugresistant A.baumannii.

Origin of nucleation and growth of extension twins in grains unsuitably oriented for twinning during deformation of Mg-1%Al

A large number of anomalous extension twins,with low or even negative twinning Schmid factors,were found to nucleate and grow in a strongly textured Mg-1Al alloy during tensile deformation along the extruded direction.The deformation mechanisms responsible for this behaviour were investigated through in-situ electron back-scattered diffraction,grain reference orientation deviation,and slip trace-modified lattice rotation.It was found that anomalous extension twins nucleated mainly at the onset of plastic deformation at or near grain boundary triple junctions.They were associated with the severe strain incompatibility between neighbour grains as a result from the differentbasal slip-induced lattice rotations.Moreover,the anomalous twins were able to grow with the applied strain due to the continuous activation ofbasal slip in different neighbour grains,which enhanced the strain incompatibility.These results reveal the complexity of the deformation mechanisms in Mg alloys at the local level when deformed along hard orientations.

Diagnostic Study of an Extreme Explosive Cyclone over the Kuroshio/Kuroshio Extension Region

Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension region.The most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-April)was studied to reveal the variations of the key factors at different explosive-developing stages.This EC had weak low-level baroclinicity,mid-level cyclonic-vorticity advection,and strong low-level water vapor convergence at the initial explosive-developing stage.The low-level baroclinicity and mid-level cyclonic-vorticity advection increased substantially during the maximum-deepening-rate stage.The diagnostic analyses using the Zwack-Okossi equation showed that diabatic heating was the main contributor to the initial rapid intensification of this EC.The cyclonic-vorticity advection and warm-air advection enhanced rapidly in the middle and upper troposphere and contributed to the maximum rapid intensification,whereas the diabatic heating weakened slightly in the mid-low troposphere.The relative contribution of the diabatic heating decreased from the initial explosive-developing stage to the maximum-deepening-rate stage due to the enhancement of other factors(the cyclonic-vorticity advection and warm-air advection).Furthermore,the physical factors contributing to this EC varied with the explosive-developing stage.The non-key factors at the initial explosive-developing stage need attention to forecast the rapid intensification.

Estimation of Displacement and Extension due to Reverse Drag of Normal Faults: Forward Method

In the case of reverse drag of normal faulting, the displacement and horizontal extension are determined based on the established equations for the three mechanisms: rigid body, vertical shear and inclined shear. There are three sub-cases of basal detachment for the rigid body model: horizontal detachment, antithetic detachment and synthetic detachment. For the rigid body model, the established equations indicate that the total displacement on the synthetic base (Dt2) is the largest, that on the horizontal base (Dt1) is moderate, and that on the antithetic base (Dt3) is the smallest. On the other hand, the value of (Dt1) is larger than the displacement for the vertical shear (Dt4). The value of (Dt1) is larger than or less than the displacement for the inclined shear (Dt5) depending on the original fault dip δ0, bedding angle θ, and the angle of shear direction β. For all original parameters, the value of Dt5 is less than the value of Dt4. Also, by comparing three rotation mechanisms, we find that the inclined shear produces largest extension, the rigid body model with horizontal detachment produces the smallest extension, and the vertical shear model produces moderate extension.

Analysis of the Digital Skill Gap of Agricultural Extension Personnel in South-East, Nigeria

The study analysed the digital skill gap of agricultural extension personnel on the use of digital technologies for extension services delivery in South-East, Nigeria. The specific objectives were to describe the socioeconomic characteristics of agricultural extension personnel in South-East Nigeria and identify the digital skill gaps among agricultural extension personnel in the area of study. Purposive sampling technique was used to select 364 Agricultural Extension personnel for the study. Data were collected through the use of structured questionnaire and were analysed using simple descriptive statistical tools such as percentages, mean score, and standard deviation. Findings indicated that most of the personnel were male (57.8%), within the age bracket of 38 - 47 years (62.9%), had B.Sc./HND as their highest educational qualification (74.7%), married (86.3%), and had a household size of 6 - 10 Persons (57.7%). It was further revealed that the majority (70.1%) were members of professional organization, earned a monthly income of N50,001.00 - N100,000.00 (65.7%), had a work experience of 11 - 15 years (51.1%), and owned a smartphone/ iPad/laptop (91.5%). Findings further indicated that they had moderate skill gap in Basic Computer skills (Mean = 4.32), and digital communication and collaboration skills (Mean = 4.26). Findings also showed that they had a high skill gap in digital technical skills (Mean = 2.46), digital data analysis skills (Mean = 2.09), digital content creation skills (Mean = 2.43), digital ethical skills (Mean = 2.79), multimedia production skills (Mean = 2.81), and video library management skills (Mean = 2.39). The study concluded that though there exists a high digital skill gap among agricultural extension personnel in South-East, Nigeria, their socioeconomic characteristics are capable of supporting the implementation of digital extension services in the area. The study recommended that the management of Agricultural Development Programs in South-East, Nigeria, should provide digital training for extension personnel to close the digital skill gap that currently exists among the personnel.

Comparative Study of the Socioeconomic Characteristics and Digital Literacy Level of Agricultural Extension Personnel in Imo and Ebonyi States, South-East, Nigeria

The study comparatively analysed the socioeconomic characteristics and digital literacy level of Agricultural Extension personnel (AEP) in Ebonyi and Imo States, South-East, Nigeria. The specific objectives were to describe the socioeconomic characteristics of agricultural extension personnel in Ebonyi and Imo States, and to ascertain the digital literacy level of AEP in the studied states. Purposive sampling technique was used to select 312 Agricultural Extension personnel (132 from Ebonyi State Agricultural Development Program and 180 from Imo State Agricultural Development Program) for the study. Data were collected through the use of validated and structured questionnaire, and administered through the help of well-trained enumerators. Data were analysed using simple descriptive statistical tools such as percentages mean score, standard deviation and weighted mean. Findings indicated that they were more male in the both States (55.3% and 57.8%) for Ebonyi and Imo State respectively and that the average age of AEP in Ebonyi and Imo States were 44.7 years and 49.2 years respectively. It was further revealed that the majority (77.3% and 82.8%) had B.Sc./HND as their highest academic qualifications, belonged to professional organisations (62.1% and 75%), and were earning an average monthly income of N58,798 and N62,648 for Ebonyi and Imo State respectively. Also, it was revealed that their mean years of service were 12.4 years and 13.4 years for Ebonyi and Imo State respectively. Almost all of them (87.9% and 95.0%) own a smartphone, had access to the internet (80.3% and 90.0%), but do not own a laptop/ipad (82.6% and 72.8%) for Ebon-yi and Imo State respectively. Results further revealed that Agricultural extension personnel in both Ebonyi and Imo State respectively had low digital literacy level ( = 2.41 and 2.32). The study concluded that AEP in Ebonyi and Imo State respectively had similar socioeconomic characteristics and low level of digital literacy. The study recommended that the management of ADPs in both Ebonyi and Imo State should ensure the training of AEP in digital skills to enhance their digital literacy level to enable them use digital technologies in their work.

Longitudinally extensive transverse myelitis associated with scrub typhus:A case report

Rationale:Longitudinally extensive transverse myelitis(LETM)is a rare inflammatory demyelinating disease predominantly associated with autoimmune and inflammatory disorders.Scrub typhus can cause a variety of neurological complications,which may result in poor recovery and long-term disability.This report reveals a rare linkage between LETM and scrub typhus.Patient concerns:A 24-year-old female presented with a history of fever for 10 days associated with progressive quadriparesis.Physical examination revealed bilateral lower limb weakness(grade 0/5)and bilateral upper limb weakness(grade 2/5)with reduced sensation below the T3 dermatome.Diagnosis:Scrub typhus presenting with longitudinally extensive transverse myelitis.Interventions:Steroid pulse therapy with antibiotics supported by early intensive rehabilitation.Outcomes:Complete recovery was achieved.Lessons:This case report highlights the importance of considering scrub typhus as a potential cause of LETM in endemic regions,particularly in patients presenting with febrile illness and neurological symptoms.

Assessing the Environmental Impact of Extensive Beef Production in Grazing Lands of Argentina

Because of environmental constraints,beef cattle was for more than a century the only viable farming option in the extensive semiarid and subhumid lands of Argentina and the main source of nutrients for humans as well.However,a growing concern and criticism have risen today about its possible negative impact on the climate and the environment.These worries tend to affect current public opinions,national policies,and international trade.Based on 40 beef cattle farms scattered across different semiarid and subhumid regions of Argentina,here we evaluated the impact of extensive cattle production on carbon,water,and nutrient pollution.Life-Cycle Assessment(LCA)and Land-Based Assessment(LBA)were the two approaches we used here to compare the environmental impact of beef production.While the environmental footprint(EF)resulting from LCA expresses the impact per unit of food,the environmental balance(EB),derived from LBA,aims at quantifying the impact per unit of land.As such,the EB considers both negative and positive impacts on the farm as an integrated system.Following standardized procedures,we evaluated EF and EB up to the farm gate,leaving aside delocalized post-farm impacts such as those of processing,packaging,and transportation that occur beyond the farm gate.In agreement with previous evidence,our results show that the EF tends to decrease as per-head production increases.Correlation coefficients and statistical significance were the following for carbon(R=−0.574;p<0.01),water(R=−0.561;p<0.01),and N(R=−0.704;p<0.01)and Phosphorus(P)pollution(R=−0.802;p<0.01)footprints.On the contrary,the EB seems to be highly sensitive,and as per-hectare beef production increases.Correlations were the following for carbon emissions(CE:R=0.955;p<0.01),water consumption(WC:R=0.822;p<0.01),nitrogen excretion(NE:R=0.948;p<0.01)and phosphorus excretion(PE:R=0.945;p<0.01).What our results suggest is that the notion of EF is useful to evaluate the environmental impact in intensive beef production systems,and the EB is suitable to assess the impact of the extensive ones.In practice,both approaches provide different perspectives on the environmental-impact problem and they should be complementary used.We concluded that the methodological rigidity of EF does not allow proper discrimination among farms in the extensive systems.On the contrary,the EB approach tended to be highly sensitive to detecting differences between individual farms and farmers,thus allowing the identification of successful options for extensive beef production in terms of public image,policy-making,and commercial opportunities.

Wellbore Cleaning Degree and Hydraulic Extension in Shale Oil Horizontal Wells

The efficient development and exploitation of shale oil depends on long-distance horizontal wells. As the degreeof cleaning of the wellbore plays a key role in these processes, in this study, this problem is investigated experimentallyby focusing on the dimensionless cuttings bed height. A method is proposed to calculate the horizontalwellhydraulic extension taking into account the influence of the wellbore cleaning degree on the wellborepressure distribution and assess the effect of a variety of factors such as the bottom hole pressure, the circulatingpressure drop, the drilling pump performance and the formation properties. The analysis shows that the hydraulicextension of horizontal wells decreases with an increase in the cuttings bed height, and the higher the displacementof drilling fluid, the faster the hydraulic extension declines. The annular pressure drop of the horizontalsection increases with the increase of the cuttings bed height, resulting in a higher bottom-hole pressure. Severalarguments are provided to guide the safe drilling of shale oil horizontal wells and overcome the limits of currenttechnological approaches.

Extensively drug-resistant Salmonella typhi causing rib osteomyelitis: A case report

Rationale:Salmonella(S.)typhi is a rare cause of osteomyelitis in immunocompetent adults.Extensive drug resistance(XDR)may lead to more complicated cases of S.typhi osteomyelitis.Patient concern:A 55-year-old female presented with a persistent low-grade fever and a swelling on her lower left chest with a sinus discharging purulent fluid for the past 8 months.Her symptoms had been unresponsive to previous anti-microbial therapy.Diagnosis:Rib osteomyelitis caused by XDR S.typhi.Interventions:Surgical wound debridement,left 7th-9th rib resection and intravenous Ⅳ meropenem were done.Outcome:Fever resolved and left-sided swelling resected without recurrence.Lessons:The prevalence of XDR S.typhi is growing in South Asia and should be considered as the differential diagnosis of chronic osteomyelitis.

The Effects of Infrastructure Projects on House Prices and Rents:Evidence from the HS2 Extension Cancellation in the UK

This paper uses the HS2 extension cancellation in November 2021 as a quasi-experiment to study its impact on house prices and rents in Leeds.Using a DiD approach on repeat sales and monthly rents,I compare property values near the HS2 station and proposed construction site before and after the announcement.Results show a 3.6%decrease in house prices and a 3.9%decline in rents near the station,while properties near the construction site experienced a 2.4%increase in prices and a 2.1%rise in rents.This is the first paper to analyse the HS2 cancellation effect using panel data methods.

Reverse effect of curcumin on CDDP-induced drug-resistance via Keap1/p62-Nrf2 signaling in A549/CDDP cell

Objective: To assess the effect of curcumin on CDDP-induced drug resistance and explore the underlying molecular mechanism through Nrf2 system and autophagy pathway.Methods: A drug-resistant cell model was established by exposing A549/CDDP cell to2 μg/mL CDDP. A549/CDDP cell was treated with 20 μg/mL CDDP and 10 μM curcumin. The cell viability and apoptosis level, the signals of Keap1/P62-Nrf2 and autophagy pathway were analyzed.Results: CDDP induction promoted drug-resistant phenotype in A549/CDDP cell and activated autophagy as well as Nrf2 signals in A549/CDDP cell. Meanwhile, curcumin combination attenuated autophagy and Nrf2 activation induced by CDDP, and reversed the drug-resistant phenotype. Notably, curcumin combination augmented Keap1 transcription. Furthermore, Keap1 ablation with short hairpin RNAs hampered the efficacy of curcumin, suggesting Keap1 played a crucial role on reversal effect of curcumin.Conclusions: The present findings demonstrate that CDDP promotes abnormal activation of Nrf2 pathway and autophagy, leading to drug resistance of A549/CDDP cell.Curcumin attenuates this process and combat drug-resistance through its potent activation on Keap1 transcription, which is essential for interplay between oxidative stress induced Nrf2 activation and autophagy/apoptosis switch.

Comparison of extended spectrum β-lactamasesproducing Escherichia coli with non-ESBLsproducing E.coli:drug-resistance and virulence

The virulent factors of Escherichia coil （E.cofi） play an important role in the process of pathopoiesis. The study aimed to compare drug-resistant genes and virulence genes between extended spectrum β-1actamases （ESBLs）-producing E.coli and non-ESBLs-producing E.cofi to provide a reference for physicians in management of hospital infection. From October 2010 to August 2011,96 drug-resistant strains of E. coli isolated were collected from the specimens in Qingdao Municipal Hospital, Qingdao, China. These bacteria strains were divided into a ESBLs-producing group and a non-ESBLs-producing group. Drug sensitivity tests were performed using the Kirby-Bauer （K-B） method. Disinfectant gene, qacEAl-sull and 8 virulence genes （CNF2, hlyA, eaeA, VT1, est, bfpA, elt, and CNF1） were tested by polymerase chain reaction （PCR）. Among the 96 E.coli isolates, the ESBLs-producing E.coli comprised 46 （47.9%） strains and the non-ESBLs-producing E.cofi consisted of 50 （52.1%） strains. The detection rates of multiple drug-resistant strain, qacEAl-sull, CNF2, hlyA, eaeA,VT1, est, bfpA, elt, and CNF1 in 46 ESBLs-producing E.coli isolates were 89.1%, 76.1%, 6.5%, 69.6%, 69.6%, 89.1%, 10.9%, 26.1%, 8.7%, and 19.6%, respectively. In the non-ESBLs-producing E.cofi strains, the positive rates of multiple drug-resistant strain, qacEAl-sull, CNF2, hlyA, eaeA, VT1, est, bfpA, elt, and CNF1 were 62.0%, 80.0%, 16.0%, 28.0%, 64.0%, 38.0%, 6.0%, 34.0%, 10.0%, and 24.0%, respectively. The difference in the detection rates of multiple drug-resistant strain, hlyA and VT1 between the ESBLs-producing E.cofi strains and the non-ESBLs-producing E.cofi strains was statistically significant （P〈0.05）. The positive rate of multiple drug-resistant strains is higher in the ESBLs-producing strains than in the non-ESBLs-producing strains. The expression of some virulence genes hlyA and VT1 varies between the ESBLs-producing strains and the non-ESBLs-producing strains. Increased awareness of clinicians and enhanced testing by laboratories are required to reduce treatment failures and prevent the spread of multiple drug-resistant strains.

Molecular Characterization and Drug-resistance of Mycobacterium tuberculosis Strains in Xuzhou, China

To understand the genetic diversity and drug resistance status of Mycobocterium tuberculosis （M. tuberculosis） circulating in Xuzhou of China, the spacer-oligonucleotide typing （Spoligotyping） and multi-loci VNTRs （variable number tandem repeats） analysis （MLVA） were utilized for the genotyping of the isolates. Drug susceptibility test （DST） was performed by the proportion method on the Lowenstein-Jensen （L-J） medium using isoniazid, rifampicin, ethambutol, and streptomycin. By Spoligotyping, 287 M. tuberculosis isolates were differentiated into 14 clusters. Then with 15-1oci MLVA, these strains could be divided into 32 clusters, 228 genotypes. Of 15 VNTRs, 6 loci had the highly discriminatory powers, 6 loci presented moderate discrimination and 3 loci demonstrated less polymorphism. The DST results showed that 46 strains were resistant to at least one first-line anti-tuberculosis agent. There was a difference in the isoniazid resistance between Beijing and non-Beijing genotype strains. We concluded that the combination of Spoligotyping and 15 VNTR loci as the genotyping in our study was applicable for this region, the drug resistant isolates were identified, and the Beijing family was the most prevalent genotype in the rural counties of Xuzhou.

Three-dimensional collagen-based scaffold model to study the microenvironment and drug-resistance mechanisms of oropharyngeal squamous cell carcinomas

Objective:Squamous cell carcinoma(SCC)represents the most common histotype of all head and neck malignancies and includes oropharyngeal squamous cell carcinoma(OSCC),a tumor associated with different clinical outcomes and linked to human papilloma virus(HPV)status.Translational research has few available in vitro models with which to study the different pathophysiological behavior of OSCCs.The present study proposes a 3-dimensional(3 D)biomimetic collagen-based scaffold to mimic the tumor microenvironment and the crosstalk between the extracellular matrix(ECM)and cancer cells.Methods:We compared the phenotypic and genetic features of HPV-positive and HPV-negative OSCC cell lines cultured on common monolayer supports and on scaffolds.We also explored cancer cell adaptation to the 3 D microenvironment and its impact on the efficacy of drugs tested on cell lines and primary cultures.Results:HPV-positive and HPV-negative cell lines were successfully grown in the 3 D model and displayed different collagen fiber organization.The 3 D cultures induced an increased expression of markers related to epithelial–mesenchymal transition(EMT)and to matrix interactions and showed different migration behavior,as confirmed by zebrafish embryo xenografts.The expression of hypoxia-inducible factor 1α(1α)and glycolysis markers were indicative of the development of a hypoxic microenvironment inside the scaffold area.Furthermore,the 3 D cultures activated drug-resistance signaling pathways in both cell lines and primary cultures.Conclusions:Our results suggest that collagen-based scaffolds could be a suitable model for the reproduction of the pathophysiological features of OSCCs.Moreover,3 D architecture appears capable of inducing drug-resistance processes that can be studied to better our understanding of the different clinical outcomes of HPV-positive and HPV-negative patients with OSCCs.

Investigation of immune escape-associated mutations of hepatitis B virus in patients harboring hepatitis B virus drug-resistance mutations

It is unclear whether immune escape-associated mutations in the major hydrophilic region of hepatitis B virus surface antigen(HBsAg)are associated with nucleoside/nucleotide analog resistance.AIM To evaluate the association between immune escape-associated mutations and nucleoside/nucleotide analog resistance mutations.METHODS In total,19440 patients with chronic hepatitis B virus infection,who underwent resistance testing at the Fifth Medical Center of Chinese PLA General Hospital between July 2007 and December 2017,were enrolled.As determined by sequence analysis,6982 patients harbored a virus with resistance mutations and 12458 harbored a virus lacking resistance mutations.Phenotypic analyses were performed to evaluate HBsAg production,replication capacity,and drug-induced viral inhibition of patient-derived drug-resistant mutants with or without the coexistence of sA159V.RESULTS The rate of immune escape-associated mutation was significantly higher in 9 of the 39 analyzed mutation sites in patients with resistance mutations than in patients without resistance mutations.In particular,these mutations were sQ101H/K/R,sS114A/L/T,sT118A/K/M/R/S/V,sP120A/L/Q/S/T,sT/I126A/N/P/S,sM133I/L/T,sC137W/Y,sG145A/R,and sA159G/V.Among these,sA159V was detected in 1.95%(136/6982)of patients with resistance mutations and 1.08%(134/12,458)of patients lacking resistance mutations(P<0.05).The coexistence of sA159V with lamivudine(LAM)and entecavir(ETV)-resistance mutations in the same viral genome was identified during follow-up in some patients with drug resistance.HBsAg production was significantly lower and the replication capacity was significantly higher,without a significant difference in LAM/ETV susceptibility,in sA159V-containing LAM/ETV-resistant mutants than in their sA159V-lacking counterparts.CONCLUSION In summary,we observed a close link between the increase in certain immune escape-associated mutations and the development of resistance mutations.sA159V might increase the fitness of LAM/ETV-resistant mutants under environmental pressure in some cases.

Validation of user-friendly models predicting extracapsular extension in prostate cancer patients

Objective:There are many models to predict extracapsular extension(ECE)in patients with prostate cancer.We aimed to externally validate several models in a Japanese cohort.Methods:We included patients treated with robotic-assisted radical prostatectomy for prostate cancer.The risk of ECE was calculated for each patient in several models(prostate side-specific and non-side-specific).Model performance was assessed by calculating the receiver operating curve and the area under the curve(AUC),calibration plots,and decision curve analyses.Results:We identified ECE in 117(32.9%)of the 356 prostate lobes included.Patients with ECE had a statistically significant higher prostate-specific antigen level,percentage of positive digital rectal examination,percentage of hypoechoic nodes,percentage of magnetic resonance imaging nodes or ECE suggestion,percentage of biopsy positive cores,International Society of Urological Pathology grade group,and percentage of core involvement.Among the sidespecific models,the Soeterik,Patel,Sayyid,Martini,and Steuber models presented AUC of 0.81,0.78,0.77,0.75,and 0.73,respectively.Among the non-side-specific models,the memorial Sloan Kettering Cancer Center web calculator,the Roach formula,the Partin tables of 2016,2013,and 2007 presented AUC of 0.74,0.72,0.64,0.61,and 0.60,respectively.However,the 95%confidence interval for most of these models overlapped.The side-specific models presented adequate calibration.In the decision curve analyses,most models showed net benefit,but it overlapped among them.Conclusion:Models predicting ECE were externally validated in Japanese men.The side-specific models predicted better than the non-side-specific models.The Soeterik and Patel models were the most accurate performing models.