Upregulation of POC1A in lung adenocarcinoma promotes tumour progression and predicts poor prognosis.

Lung adenocarcinoma (LUAD) is characterized by a high incidence rate and mortality. Recently, POC1 centriolar protein A (POC1A) has emerged as a potential biomarker for various cancers, contributing to cancer onset and development. However, the association between POC1A and LUAD remains unexplored. We extracted The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) data sets to analyse the differential expression of POC1A and its relationship with clinical stage. Additionally, we performed diagnostic receiver operator characteristic (ROC) curve analysis and Kaplan-Meier (KM) survival analysis to assess the diagnostic and prognostic value of POC1A in LUAD. Furthermore, we investigated the correlation between POC1A expression and immune infiltration, tumour mutation burden (TMB), immune checkpoint expression and drug sensitivity. Finally, we verified POC1A expression using real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC). Cell experiments were conducted to validate the effect of POC1A expression on the proliferation, migration and invasion of lung cancer cells. POC1A exhibited overexpression in most tumour tissues, and its overexpression in LUAD was significantly correlated with late-stage presentation and poor prognosis. The high POC1A expression group showed lower levels of immune infiltration but higher levels of immune checkpoint expression and TMB. Moreover, the high POC1A expression group demonstrated sensitivity to multiple drugs. In vitro experiments confirmed that POC1A knockdown led to decreased proliferation, migration, and invasion of lung cancer cells. Our findings suggest that POC1A may contribute to tumour development by modulating the cell cycle and immune cell infiltration. It also represents a potential therapeutic target and marker for the diagnosis and prognosis of LUAD.

Label-Free Mapping of Multivalent Binding Pathways with Ligand-Receptor-Anchored Nanopores.

Understanding single-molecule multivalent ligand-receptor interactions is crucial for comprehending molecular recognition at biological interfaces. However, label-free identifications of these transient interactions during multistep binding processes remains challenging. Herein, we introduce a ligand-receptor-anchored nanopore that allows the protein to maintain structural flexibility and favorable orientations in native states, mapping dynamic multivalent interactions. Using a four-state Markov chain model, we clarify two concentration-dependent binding pathways for the Omicron spike protein (Omicron S) and soluble angiotensin-converting enzyme 2 (sACE2): sequential and concurrent. Real-time kinetic analysis at the single-monomeric subunit level reveals that three S1 monomers of Omicron S exhibit a consistent and robust binding affinity toward sACE2 (-13.1 ± 0.2 kcal/mol). These results highlight the enhanced infectivity of Omicron S compared to other homologous spike proteins (WT S and Delta S). Notably, the preceding binding of sACE2 to Omicron S facilitates the subsequent binding steps, which was previously obscured in bulk measurements. Our single-molecule studies resolve the controversy over the disparity between the measured spike protein binding affinity with sACE2 and the viral infectivity, offering valuable insights for drug design and therapies.

Computational design of a reliable intermediate-band photovoltaic absorber based on diamond.

To reduce the wide bandgap of diamond and expand its applications in the photovoltaic fields, a diamond-based intermediate-band (IB) material C-Ge-V alloy was designed by first-principles calculations. By replacing some C with Ge and V in the diamond, the wide bandgap of the diamond can be reduced sharply and a reliable IB, which is mainly formed by the d states of V, can be formed in the bandgap. With the increase of Ge content, the total bandgap of the C-Ge-V alloy will be reduced and close to the optimal value of an IB material. At a relatively low atomic concentration of Ge (below 6.25%), the IB formed in the bandgap is partially filled and varies little with the concentration of Ge. When further increasing the content of Ge, the IB moves close to the conduction band and the electron filling in the IB increases. The 18.75% content of Ge might be the limitation to form an IB material, and the optimal content of Ge should be between 12.5% and 18.75%. Compared with the content of Ge, the distribution of Ge has a minor effect on the band structure of the material. The C-Ge-V alloy shows strong absorption for the sub-bandgap energy photons, and the absorption band generates a red-shift with the increase of Ge. This work will further expand the applications of diamond and be helpful to develop an appropriate IB material.

Early versus the traditional start of oral intake following esophagectomy for esophageal cancer: a systematic review and meta-analysis.

BACKGROUND: Nil by mouth is considered the standard of care during the first days following esophagectomy. However, with the routine implementation of enhanced recovery after surgery, early oral intake is more likely to be the preferred mode of nutrition following esophagectomy. The present study aims to evaluate the safety and effectiveness of early oral intake following esophagectomy for esophageal cancer. METHODS: Comprehensive literature searches were conducted using PubMed, Web of Science, Embase, and Cochrane Library. Weighted mean differences (WMD) and odds ratios (OR) with 95% confidence intervals (CI) were calculated as the effect sizes for continuous and dichotomous variables, respectively. RESULTS: Fourteen studies with a total of 1947 patients were included. Length of hospital stay (WMD = - 3.94, CI: - 4.98 to - 2.90; P < 0.001), the time to first flatus (WMD = - 1.13, CI: - 1.25 to - 1.01; P < 0.001) and defecation (WMD = - 1.26, CI: - 1.82 to - 0.71; P < 0.001) favored the early oral intake group. There was no statistically significant difference in mortality (OR = 1.23, CI: 0.45 to 3.36; P = 0.69). Early oral intake also did not increase the risk of pneumonia and overall postoperative complications. CONCLUSIONS: Current evidence indicates early oral intake following esophagectomy seems to be safe and effective. It may be the preferred mode of nutrition following esophagectomy. However, more high-quality studies are still needed to further validate this conclusion.

Esophagectomy versus definitive chemoradiotherapy as initial treatment for clinical stage I esophageal cancer: a systematic review and meta-analysis.

BACKGROUND: Esophagectomy and definitive chemoradiotherapy are commonly used in the treatment of stage I esophageal cancer (EC). The present study aims to compare the efficacy and safety of esophagectomy and definitive chemoradiotherapy as the initial treatment for clinical stage I EC. METHODS: This study was registered with the International Prospective Register of Systematic Reviews (CRD42020197203). Relevant studies were identified through PubMed, Web of Science, EMBASE, and Cochrane Library from database inception to June 30, 2020. Hazard ratio (HR) with 95% confidence intervals (CI) was employed to compare overall survival (OS) and progression-free survival (PFS). Odds ratio (OR) with 95% CI was employed to compare treatment-related death, complications, and tumor recurrence. RESULTS: A total of 13 non-randomized controlled studies involving 3,346 patients were included. Compared with definitive chemoradiotherapy, esophagectomy showed an improved OS (HR 0.69, 95% CI 0.55-0.86; P < 0.001), PFS (HR 0.47, 95% CI 0.33-0.67; P < 0.001), and a lower risk of tumor recurrence (OR 0.43, 95% CI 0.30-0.61; P < 0.001). There was no significant difference in the incidence of complications (OR 1.11, 95% CI 0.75-1.65; P = 0.60) and treatment-related death (OR 1.15, 95% CI 0.31-4.30; P = 0.84) between the two treatments. CONCLUSIONS: Current evidence shows esophagectomy has superior survival benefits as the initial treatment for clinical stage I EC. It is still the preferred choice for patients with clinical stage I EC. However, future high-quality randomized controlled trials are needed to validate this conclusion.

Subxiphoid versus intercostal video-assisted thoracic surgery for lung resection: a meta-analysis.

INTRODUCTION: To systematically evaluate the safety and advantages of subxiphoid approach video-assisted thoracic surgery (SA-VATS) compared with intercostal approach video-assisted thoracic surgery (IA-VATS) for lung resection, we conducted a meta-analysis of the current literature. MATERIAL AND METHODS: The literature search was conducted in PubMed, Web of Science, Cochrane Library, Embase, and China National Knowledge Infrastructure. RevMan 5.3 software was used to perform this meta-analysis. RESULTS: Eleven studies involving 934 patients were included. Compared with patients in the IA-VATS group, those in the SA-VATS group had lower pain scores on the day of the operation and at 24 h, 48 h and 72 h after the operation (p < .001) and suffered from less postoperative paraesthesia at the first, third and sixth months after the operation (p < .001). Moreover, there was no statistically significant difference between the two groups regarding postoperative complications, intraoperative blood loss, length of hospital stay, drainage amount, or chest tube duration. However, SA-VATS had a longer operative time (p < .001). CONCLUSIONS: SA-VATS is a safe surgical technique and has superior postoperative outcomes over IA-VATS for lung resection in terms of acute postoperative pain and chronic postoperative paraesthesia.

A Meta-analysis of Jejunostomy Versus Nasoenteral Tube for Enteral Nutrition Following Esophagectomy.

BACKGROUND: Postoperative nutritional therapy is of paramount importance for patients undergoing esophagectomy. The jejunostomy and nasoenteral tube are the popular routes for nutritional therapy. However, which one is the preferred route is unclear. This study aims to analyze the differences in safety and efficacy of the two routes for nutritional therapy. MATERIALS AND METHODS: PubMed, Web of Science, Cochrane Library, and EMBASE (till September 17, 2020) were searched. The primary outcome was postoperative pneumonia. Secondary outcomes were the length of hospital stays (LOS), bowel obstruction, catheter dislocation, anastomotic leakage, overall postoperative complications, and postoperative albumin. Weighted mean differences (WMD) and odds ratios (OR) were calculated for statistical analysis. RESULTS: Ten studies involving a total of 1,531 patients in the jejunostomy group and 1,375 patients in the nasoenteral tube group were included. Compared with patients in the nasoenteral tube group, those in the jejunostomy group had a lower incidence of postoperative pneumonia (OR = 0.68, P < 0.001), shorter LOS (WMD = -0.85, P < 0.001), and lower risk of catheter dislocation (OR = 0.15, P = 0.001). There were no significant differences in the incidence of anastomotic leakage (OR = 0.84, P = 0.43), overall postoperative complications (OR = 0.87, P = 0.59), and postoperative albumin (WMD = -0.40, P = 0.24). However, patients in the jejunostomy group had a higher risk of bowel obstruction (OR = 8.42, P = 0.002). CONCLUSIONS: Jejunostomy for enteral nutrition showed superior outcomes in terms of postoperative pneumonia, LOS, and catheter dislocation. Jejunostomy may be the preferred enteral nutritional route following esophagectomy.

Is it necessary to routinely perform feeding jejunostomy at the time of esophagectomy? A systematic review and meta-analysis.

Feeding jejunostomy (FJ) is a routine procedure at the time of esophagectomy in some centers. With the widespread popularization of enhanced recovery after surgery, the necessity of FJ has been increasingly questioned. This study aims to analyze the differences in safety and effectiveness between with (FJ group) or without (no-FJ group) performing FJ at the time of esophagectomy. PubMed, Embase, Web of Science, and Cochrane Library were comprehensively searched for relevant studies, including randomized controlled trials and cohort studies. The primary outcome was the length of hospital stay (LOS). Secondary outcomes were overall postoperative complications, postoperative pneumonia, intestinal obstruction, and weight loss at 3 and 6 months after esophagectomy. Weighted mean differences (WMD) and odds ratios (OR) were calculated for statistical analysis. About 12 studies comprising 2,173 patients were included. The FJ group had a longer LOS (WMD = 2.05, P = 0.01) and a higher incidence of intestinal obstruction (OR = 11.67, P < 0.001) than the no-FJ group. The incidence of overall postoperative complications (OR = 1.24, P = 0.31) and postoperative pneumonia (OR = 1.43, P = 0.13) were not significantly different, nor the weight loss at 3 months (WMD = 0.58, P = 0.24) and 6 months (P > 0.05) after esophagectomy. Current evidence suggests that routinely performing FJ at the time of esophagectomy appears not to generate better postoperative outcomes. FJ may need to be performed selectively rather than routinely. More studies are required to further verify.

Haplotype-based association of two SNPs in miR-423 with unexplained recurrent pregnancy loss in a Chinese Han population.

MicroRNAs (miRNAs) regulate diverse cellular processes such as cell differentiation, proliferation and apoptosis. Mutation in miRNAs results in various pathological conditions such as inflammation, viral infections, neurodegeneration, and autoimmunity. We have evaluated the association of miR-423 rs6505162C>A and rs8067576 A>T among patients with recurrent pregnancy loss (RPL) and controls from North China. Our study found that one SNP rs6505162C>A in miR-423 coding region was associated with the increase risk of humanunexplained RPL (URPL), but no differences were found in another SNP rs8067576 A>T. However, in two-locus haplotype analysis, miR-423-CC/TT haplotype was associated with an increased risk of URPL. The level of mature miR-423 was obviously down-regulated in cells transfected with miR-423-CC/TT haplotype. miR-423-CC/TT haplotype inhibited HTR-8/SVneo cells proliferation and migration and promoted cells apoptosis. Further experiments identified that mesoderm development candidate 1 (MESDC1) was a functionally relevant target of miR-423, and its expression was reversely regulated by miR-423. More importantly, dual-luciferase assay indicated miR-423-CC/TT haplotype decreasing miR-423 expression, could up-regulate MESDC1 expression. Collectively, our data suggest that miR-423-CC/TT haplotype in pre-miR-423 may aggravate the risk of developing URPL by influencing the level of mature miR-423 and its target gene MESDC1.

Pulmonary contusion during the COVID-19 pandemic: challenges in diagnosis and treatment.

Managing patients with pulmonary contusion safely and effectively during the coronavirus disease 2019 (COVID-19) pandemic is challenging. This retrospective study analyzes the clinical data of 29 consecutive patients with pulmonary contusion, including two with COVID-19, at Tongji Hospital, Wuhan, China, in January and February, 2020. We analyzed the clinical manifestations, laboratory test results, computed tomography (CT) images, treatment, and clinical outcomes. The two patients with pulmonary contusion and COVID-19 had increased leukocyte and neutrophil counts, similar to the patients with pulmonary contusion alone. Interestingly, both these patients had subpleural ground glass opacity on CT images as a typical manifestation of COVID-19. All 29 patients were treated conservatively, including with closed thoracic drainage, instead of with thoracotomy. Six patients died of ARDS or craniocerebral injury, but the others stabilized. During the COVID-19 pandemic, patients with pulmonary contusion should be tested for SARS-CoV-2 and unless critical, thoracotomy should be avoided.

Effect of Osimertinib on the expression of serum mmp-7 and mmp-9 in patients with non-small cell lung cancer.

The purpose was to investigate the efficacy and safety of Osimertinib in the treatment of advanced non-small cell lung cancer and to analyze its effects on the expression of serum matrix metalloproteinase-7 (MMP-7) and matrix metallo-proteinase-9 (MMP-9). Eighty patients were equally divided into observation and control group. The observation group was given Osimertinib combined with conventional chemotherapy and the other was treated with conventional chemotherapy alone. The short-term efficacy, the levels of serum MMP-7, MMP-9 and adverse reactions were compared. The effectiveness and clinical benefit rate of the observation group were 62.50% and 92.50% respectively, significantly higher than the control group. There was no significant difference in MMP-7 and MMP-9 before treatment however there was a significant difference after treatment, and the serum MMP-7 & MMP-9 levels showed a trend of increasing with decreasing efficacy. After treatment, comparing with control group, serum MMP-7 and MMP-9 levels were significantly lower, the Karnofsky score was significantly higher, and the improvement effect of the quality of life was statistically significant. Besides, the incidence of leukopenia, thrombocytopenia, anemia and gastrointestinal symptoms were significantly lower. In the treatment of patients with advanced non-small cell lung cancer, Osimertinib significantly reduced the expression of serum MMP-7, MMP-9, improved the clinical benefit and quality of life of patients. The clinical efficacy was significant with a high safety.

Bursicon homodimers induce innate immune by activating the expression of anti-microbial peptide genes in the shrimp Neocaridina heteropoda.

Bursicon is a neurohormone belonging to the cystine knot protein family. It consists of two subunits (burs α and burs ß) and plays a pivotal role in cuticle tanning and wing expansion in insects. Recent studies show that homologous crustacean bursicon stimulates cuticle thickening and granulation of hemocytes in the crab Callinectes sapidus. Here we investigate whether bursicon homodimers function in immunoprotective defense systems of shrimp. We found that abdominal ganglion was the main neurohemal release site of bursicon in Neocaridina heteropoda. Bacterial infections induced overexpression of burs α (bursicon α) and burs ß (bursicon ß). RNAi of burs α, burs ß or both inhibited the expression of anti-microbial peptide (AMP) genes. Treating shrimp adults with r-bursicon (recombinant bursicon) homodimers led to up-regulation of three AMP genes. Besides, through the induced AMPs, r-bursicon homodimers enhanced the bacteriostasis of shrimp in vivo and in vitro. These findings demonstrate a novel function of bursicon in crustacean that it induces innate immune via up-regulating the expression of genes encoding AMPs.

Raman spectra and optical properties of the chalcogen-hyperdoped silicon: a first-principles study.

The Raman peaks observed in the ultrafast-laser induced chalcogen-hyperdoped Si are assigned to different configurations of defects formed in crystal Si. The disappearance of the Raman peaks of the chalcogen-hyperdoped Si after thermal annealing is attributed to the formation of polymers, which cannot display any Raman peaks except the strong peak of crystal Si. The imaginary parts of the dielectric functions indicate that sub-bandgap absorptions are also reduced when the chalcogen atoms combine to form a polymer. The reductions of the sub-bandgap absorptions are different for S- and Se-hyperdoped Si, which can give a good explanation for their different variations of infrared absorptance at the same annealing conditions.

Fabrication of three-dimensionally ordered macroporous TiO2 film and its application in quantum dots-sensitized solar cells.

Engineering of TiO2 photoanode is an important strategy for increasing the photovoltaic conversion efficiency of quantum dots-sensitized solar cells (QDSSCs). In this work, three-dimensional ordered macroporous (3DOM) TiO2 films are fabricated by the controlled infiltrating-calcination method using the close-packed polystyrene spheres colloidal crystals as templates. The as-prepared macroporous TiO2 films are then applied as the photoanode in colloidal CdSe QDSSCs. This structure not only facilitates the penetration of thioglycolic acid capped CdSe QDs, and thus achieving a high coverage of the internal surface with QDs sensitizer, but also exhibits a photonic band gap with tunable positions, which could enhance the light absorption. As a result, the liquid-junction QDSSCs assembled with the CdSe sensitized 3DOM TiO2 yields a power conversion efficiency of 3.60% under solar illumination of 100 mW cm-2, and this value is much higher than that of the device using nanoporous TiO2 photoanode (1.82%). Our results indicate that the 3DOM TiO2 is a promising candidate for the construction of high-efficiency QDSSCs.

Investigating an intermediate-band photovoltaic material based on scandium-hyperdoped silicon through first-principles calculations.

In the scandium-hyperdoped silicon, scandiums tend to form interstitial dimers due to their lowest formation energies. The interstitial dimers of Sc formed in silicon can introduce several intermediate-bands (IBs) in the band gap, which can lead to strong sub-band gap absorption. When the two interstitial Sc atoms get close to each other, the infrared response decreases and shifts to short wavelengths. The absorption wavelength range of the interstitial dimers covers the main solar spectrum and the two primary telecommunications wavelengths, which would make material become a high efficiency IB solar cell and promising silicon-based infrared photodetector.

Effect of scandium on the optical properties of crystalline silicon material.

We have studied the optical properties of Sc-hyperdoped crystalline silicon based on quantum calculations. We have designed several probable configurations and found that the interstitial atomic positions of Sc (ScI, ScSI, ScTI, ScHI) are stable in the silicon matrix and can largely extend the absorption range of silicon from visible to infrared. The sub-band gap light absorption is attributed to the change of band structures of silicon and its intensity depends on the atomic concentration of Sc in silicon. The special effect of Sc on the properties of silicon will extend the sensitivity of silicon-based photodetectors to near infrared wavelength range.

Association between ERCC2 Lys751Gln polymorphism and lung cancer risk: a meta-analysis involving 23,370 subjects.

Recent studies report a correlation between excision repair cross-complementing group 2 (ERCC2) Lys751Gln polymorphism and an increased risk of lung cancer, but results are controversial and inconclusive. Thus, we conducted a comprehensive meta-analysis in order to assess the correlation between them. Our study uses an odds ratio (OR) with a 95% confidence interval (95% CI) to evaluate the strength of the association; we also performed Begg's funnel plot and the Egger's test to assess the publication bias of previous articles. Finally, our meta-analysis is comprised of 28 full studies, including 23,370 subjects (10,242 cases and 13,128 controls). Our overall research shows that ERCC2 Lys751Gln polymorphism carries an increased risk of developing lung cancer (C vs. A: OR = 1.160, 95% CI = 1.081-1.245, p = .000; CC vs. AA: OR = 1.252, 95% CI = 1.130-1.388, p = .000; CA vs. AA: OR = 1.152, 95% CI = 1.060-1.252, p = .001; CC+CA vs. AA: OR = 1.186, 95% CI = 1.089-1.292, p = .000; CC vs. CA+AA: OR = 1.196, 95% CI = 1.087-1.316, p = .000). In ethnic subgroup analyses, we find a significant risk among Caucasians (C vs. A: OR = 1.106, 95% CI = 1.048-1.166, p = .000; CC vs. AA: OR = 1.233, 95% CI = 1.103-1.378, p = .000; CC+CA vs. AA: OR = 1.113, 95% CI = 1.033-1.199, p = .005; CC vs. CA+AA: OR = 1.185, 95% CI = 1.069-1.313, p = .001) and among Asians under two genetic models (CA vs. AA: OR = 1.265, 95% CI = 1.034-1.549, p = .023; CC+CA vs. AA: OR = 1.252, 95% CI = 1.015-1.544, p = .036). These results were confirmed by similar findings, demonstrated by stratified analyses in study design and histological typing. This meta-analysis indicates that ERCC2 Lys751Gln polymorphism may lead to an increased susceptibility to lung cancer risk among Caucasians and Asians.

Formation, physicochemical properties, and biological activities of theabrownins.

Theabrownins (TBs) are heterogeneous mixtures of water-soluble brown tea pigments, and important constituents to evaluate the quality of dark tea. TBs have numerous hydroxyl and carboxyl groups and are formed by the oxidative polymerization of tea polyphenols. Many biological activities attributed to TBs, including antioxidant, anti-obesity, and lipid-regulating, have been demonstrated. This review summarizes the research progress made on the formation mechanism and physicochemical properties of TBs. It also discusses their protective effects against various diseases and associated potential molecular mechanisms. Additionally, it examines the signaling pathways mediating the bioactivities of TBs and highlights the difficulties and challenges of TBs research as well as their research prospects and applications.

Life cycle assessment of sewage sludge treatment and disposal technologies based on carbon emissions and environmental impacts.

This study aimed to create a comprehensive evaluation method for sewage sludge (SS) treatment and disposal technologies, considering carbon emission and environmental impacts. Life cycle assessment (LCA) were conducted on six SS treatment and disposal technologies in China. The assessments used the IPCC emission factor approach to calculate carbon emissions and the CML2001 method to determine environmental impact factors. Additionally, a colour-coded method was implemented to quantify the evaluation results. The study found that S1 (anaerobic digestion + land application) had the lowest carbon emissions and environmental impact, making it the optimal technology. The S1 scenario had carbon emissions of 669 kg CO2(t DS)-1 and environmental impacts of 5.20E-10. A sensitivity analysis was conducted to show the impacts of each unit in the six technologies on total carbon emissions and environmental impacts. The results showed that landfilling has a high sensitivity to carbon emissions and environmental impacts. Therefore, controlling greenhouse gases and toxic substances in sludge landfills is crucial for reducing carbon emissions and environmental pollution.

MIS18A upregulation promotes cell viability, migration and tumor immune evasion in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) presents a significant global health challenge owing to its poor prognosis and high mortality rates. Despite its involvement in the initiation and progression of a number of cancer types, the understanding of the precise impact of MIS18 kinetochore protein A (MIS18A) on LUAD remains incomplete. In the present study, the role of MIS18A in LUAD was investigated by analyzing the genomic and clinical data from multiple public datasets. The expression of MIS18A was validated using reverse transcription-quantitative polymerase chain reaction, and in vitro experiments involving small interfering RNA-induced downregulation of MIS18A in lung cancer cells were conducted to further explore its impact. These findings revealed that elevated MIS18A expression in LUAD was associated with advanced clinical features and poor prognosis. Functional analysis also revealed the role of MIS18A in regulating the cell cycle and immune-related pathways. Moreover, MIS18A altered the immune microenvironment in LUAD, influencing its response to immunotherapy and drug sensitivity. The results of the in vitro experiments indicated that suppression of MIS18A expression reduced the proliferative and migratory capacities of LUAD cells. In summary, MIS18A possesses potential as a biomarker and may serve as a possible therapeutic target for LUAD, with significant implications for tumor progression by influencing both cell cycle dynamics and immune infiltration.