Suppression of Cancer Cell Stemness and Drug Resistance via MYC Destabilization by Deubiquitinase USP45 Inhibition with a Natural Small Molecule

Cancer stem cells (CSCs) play significant roles in cancer development, drug resistance and cancer recurrence. In cancer treatments based on the CSC characteristics and inducing factors, MYC is a promising target for therapeutic molecules. Although it has been regarded as an undrugable target, its stability tightly regulated by the ubiquitin-proteasome system offers a new direction for molecule targeting and cancer treatment. Herein we report our discoveries in this research area, and we have found that deubiquitinase USP45 can directly bind with MYC, resulting in its deubiquitination and stabilization. Further, USP45 overexpressing can upregulate MYC, and this overexpressing can significantly enhance cancer development, cancer cell stemness and drug resistance. Interestingly, without enhancing cancer development, MYC silencing with shRNA can only suppress USP45-induced stemness and drug resistance. Moreover, we have identified that USP45 can be specifically bound and inhibited by a natural small molecule (α-mangostin), in turn significantly suppressing USP45-induced stemness and drug resistance. Since USP45 is significantly expressed in cervical tumors, we have discovered that the combination of α-mangostin and doxorubicin can significantly inhibit USP45-induced cervical tumorigenesis in an animal model. In general, on the basis of our USP45 discoveries on its MYC deubiquitination and α-mangostin inhibition, suppressing USP45 has opened a new window for suppressing cancer development, stemness and drug resistance.

Tunable electronic properties and related functional devices for ferroelectric In2Se3/MoSSe van der Waals heterostructures

In recent years, two-dimensional (2D) materials have attracted increasing attraction in a number of scientific research fields. In particular, ferroelectric materials with reversible spontaneous electric polarization and Janus transition metal dichalcogenides (TMDs) with intrinsic dipoles exhibit novel properties for many practical applications. Here, the electronic properties of van der Waals (vdW) heterostructures consisting of In₂Se₃ and MoSSe were investigated based on a first-principles approach. It was demonstrated that four studied In₂Se₃/MoSSe heterostructures exhibited obvious band gap (E _g) differences, ranging 0.13 to 0.90 eV for PBE (0.47 to 1.50 eV for HSE06) owing to the reversible spontaneous electric polarization of In₂Se₃ and different intrinsic dipole of MoSSe, and different band alignments of type-I or type-II could also be obtained. The energy bands of the four vdW heterostructures could be obviously regulated by varying degrees of vertical (horizontal) strain and vertical interface electric field, and the E _g varied from zero to 1.27 eV. Then, M4-based mechanical switching devices and ferroelectric diodes were designed based on the significant strain and electric field function. These results provide one possible mechanism for how the polarization direction regulates the physical properties of the system due to the different charges on the two surfaces of the out-of-plane polarized ferroelectric material, which may lead to different proximity effects on the face of the material.

Roles of transducin-like enhancer of split (TLE) family proteins in tumorigenesis and immune regulation

Mammalian transducin-like enhancer of split family proteins (TLEs) are homologous to Drosophila Groucho (Gro) and are essential transcriptional repressors. Seven TLE family members, TLE1-7, have been identified to date. These proteins do not bind DNA directly; instead, they bind a set of transcription factors and thereby inhibit target gene expression. Loss of TLEs in mice usually leads to defective early development; however, TLE functions in developmentally mature cells are unclear. Recent studies have revealed that TLEs are dysregulated in certain human cancer types and may function as oncogenes or tumor suppressors in different contexts. TLE levels also affect the efficacy of cancer treatments and the development of drug resistance. In addition, TLEs play critical roles in the development and function of immune cells, including macrophages and lymphocytes. In this review, we provide updates on the expression, function, and mechanism of TLEs; discuss the roles played by TLEs in tumorigenesis and the inflammatory response; and elaborate on several TLE-associated signaling pathways, including the Notch, Wnt, and MAPK pathways. Finally, we discuss potential strategies for targeting TLEs in cancer therapy.

Identification of Candidate Genes and Regulatory Competitive Endogenous RNA (ceRNA) Networks Underlying Intramuscular Fat Content in Yorkshire Pigs with Extreme Fat Deposition Phenotypes

Intramuscular fat (IMF) content is vital for pork quality, serving an important role in economic performance in pig industry. Non-coding RNAs, with mRNAs, are involved in IMF deposition; however, their functions and regulatory mechanisms in porcine IMF remain elusive. This study assessed the whole transcriptome expression profiles of the Longissimus dorsi muscle of pigs with high (H) and low (L) IMF content to identify genes implicated in porcine IMF adipogenesis and their regulatory functions. Hundreds of differentially expressed RNAs were found to be involved in fatty acid metabolic processes, lipid metabolism, and fat cell differentiation. Furthermore, combing co-differential expression analyses, we constructed competing endogenous RNAs (ceRNA) regulatory networks, showing crosstalk among 30 lncRNAs and 61 mRNAs through 20 miRNAs, five circRNAs and 11 mRNAs through four miRNAs, and potential IMF deposition-related ceRNA subnetworks. Functional lncRNAs and circRNAs (such as MSTRG.12440.1, ENSSSCT00000066779, novel_circ_011355, novel_circ_011355) were found to act as ceRNAs of important lipid metabolism-related mRNAs (LEP, IP6K1, FFAR4, CEBPA, etc.) by sponging functional miRNAs (such as ssc-miR-196a, ssc-miR-200b, ssc-miR10391, miR486-y). These findings provide potential regulators and molecular regulatory networks that can be utilized for research on IMF traits in pigs, which would aid in marker-assisted selection to improve pork quality.

[A case report of SMILE for refractive regression nine years after myopia correction with laser in situ keratomileusis]

A myopic patient with self-reported photorefractive keratectomy 9 years ago requested small incision lenticule extraction (SMILE) as retreatment. The presence of interface bubbles while creating a corneal cap of the right eye revealed that the previous refractive surgery was laser in situ keratomileusis (LASIK). Therefore, the SMILE procedure was resumed in the right eye, but flap-lift LASIK was performed in the left eye. Postoperative follow-up showed that the vision in both eyes reached the preoperative best corrected level. SMILE may be a potential option for refractive regression after LASIK.

Female fecundability is associated with pre-pregnancy allostatic load: Analysis of a Chinese cohort

INTRODUCTION

Allostatic load (AL) is a practical index that reflects multi-system physiological changes which occur in response to chronic psychosocial stress. This study investigated the association between female pre-pregnancy allostatic load and time to pregnancy.

MATERIAL AND METHODS

We enrolled 444 women who met the inclusion criteria and were attempting to achieve pregnancy. Their allostatic load scores at baseline were evaluated by nine indicators (systolic blood pressure, diastolic blood pressure, fasting plasma glucose, plasma cortisol, noradrenaline, interleukin-6, hypersensitive C-reactive protein, high density lipoprotein cholesterol and body mass index). The participants were followed up and their pregnancy outcome ascertained 1 year later; we then calculated time-to-pregnancy. Cox models were used to estimate fecundability ratios and their 95% confidence intervals (95% CI) for different allostatic load scores.

RESULTS

The median allostatic load score was 1 with a range of 0-6. The females were divided into four groups according to allostatic load score: group A (allostatic load = 0, 150/444, 33.8%), group B (allostatic load = 1-2, 156/444, 35.1%), group C (allostatic load = 3-4, 100/444, 22.5%) and group D (allostatic load = 5-6, 38/444, 8.6%). The cumulative pregnancy rate over 12 months for the four groups (A-D) was 55.4%, 44.5%, 50.9% and 26.9%, respectively (log-rank test, p = 0.042). After adjusting for potential confounding factors, group D showed a 59% reduction of fecundability compared with group A (fecundability ratio = 0.41, 95% CI 0.21-0.83).

CONCLUSIONS

Women with a higher allostatic load score may have lower fecundability. Our findings suggest that the assessment of allostatic load during pre-conception consultation would be highly prudent.

The association between the pre-pregnancy vaginal microbiome and time-to-pregnancy: a Chinese pregnancy-planning cohort study

BACKGROUND

Although sexually transmitted infections are regarded as the main cause of tubal infertility, the association between the common vaginal microbiome and female fecundability has yet to be determined. The objective of this study was to find convincing evidence relating to the impact of the vaginal bacterial structure on the fecundability of women planning pregnancy.

METHODS

We recruited women who took part in the Free Pre-pregnancy Health Examination Project from 13 June 2018 to 31 October 2018 (n = 89, phase I) and from 1 November 2018 to 30 May 2020 (n = 389, phase II). We collected pre-pregnancy vaginal swabs from each subject; then, we followed up each subject to acquire the pregnancy-planning outcome in 1 year. In phase I, 16S rRNA gene sequencing was performed to investigate the vaginal bacterial content between the pregnancy and non-pregnancy groups. These findings were verified in phase II by applying a quantitative real-time polymerase chain reaction for the measurement of the absolute abundance of specific species. Cox models were used to estimate fecundability ratios (FR) for each vaginal microbiome type.

RESULTS

In phase I, 59.6% (53/89) of women became pregnant within 1 year. The principal coordinate analysis showed that the pre-pregnancy vaginal microbial community structures of the pregnant and non-pregnant groups were significantly different (PERMANOVA test, R² = 0.025, P = 0.049). The abundance of the genus Lactobacillus in the pregnancy group was higher than that of the non-pregnant group (linear discriminant analysis effect size (LDA) > 4.0). The abundance of the genus Gardnerella in the non-pregnant group was higher than those in the pregnant group (LDA > 4.0). In phase II, female fecundability increased with higher absolute loads of Lactobacillus gasseri (quartile Q4 vs Q1, FR = 1.71, 95%CI 1.02-2.87) but decreased with higher absolute loads of Fannyhessea vaginae (Q4 vs Q1, FR = 0.62, 95%CI 0.38-1.00). Clustering analysis showed that the vaginal microbiome of type D (characterized by a higher abundance of Lactobacillus iners, a lower abundance of Lactobacillus crispatus and Lactobacillus gassri) was associated with a 55% reduction of fecundability (FR = 0.45, 95%CI 0.26-0.76) compared with type A (featuring three Lactobacillus species, low Gardnerella vaginalis and Fannyhessea vaginae abundance).

CONCLUSIONS

This cohort study demonstrated an association between the pre-pregnancy vaginal microbiome and female fecundability. A vaginal microbiome characterized by a higher abundance of L. iners and lower abundances of L. crispatus and L. gasseri appeared to be associated with a lower fecundability. Further research now needs to confirm whether manipulation of the vaginal microenvironment might improve human fecundability.

[Clinical characteristics and risk factors of lower extremity arterial disease in patients with diabetic foot ulcer]

OBJECTIVE

To investigate the clinical characteristics of lower extremity arterial disease (LEAD) and its risk factors in patients with diabetic foot ulcer (DFU).

METHODS

We retrospectively collected the clinical and follow-up data of 650 patients with DFU treated in the Department of Endocrinology and Metabolism of Nanfang Hospital between January, 2017 and December, 2019. We compared the data between patients who had LEAD and those without LEAD and used a multivariate logistic regression model to analyze the risk factors of LEAD in DFU patients.

RESULTS

Among the 650 DFU patients, 470 (72.4%) had LEAD. The patients were followed up for a mean of 3.5 months, and the mean healing time of DFU was 2.55 months; healing of DFU occurred in 453 patients and 183 patients received amputation. The patients with LEAD and those without LEAD differed significantly in age, hospitalization costs, diastolic blood pressure (DBP), glycated hemoglobin, blood lipid levels, disease course, ankle brachial index, healing time, smoking history, clinical outcomes, Wagner grade and imaging results (P < 0.05). Multivariate logistic regression analysis identified age (OR=1.070, 95% CI: 1.049-1.091), smoking history (OR= 2.013, 95% CI: 1.268-3.195), and a decreased DBP (OR=0.980, 95% CI: 0.963-0.997) as independent risk factors for LEAD in DFU patients. A prolonged healing time was a prominent clinical feature of DFU complicated by LEAD.

CONCLUSION

DFU patients have a high incidence of LEAD, which leads to high rates of disability and mortality and is associated with an advanced age, high smoking rate and longer healing time. A decreased DBP is also a risk factor for LEAD in DFU patients.

[Effect and influence factors of cardiopulmonary resuscitation in children with congenital heart disease in pediatric intensive care unit]

Objective: To investigate the prognostic factors of children with congenital heart disease (CHD) who had undergone cardiopulmonary resuscitation (CPR) in pediatric intensive care unit (PICU) in China. Methods: From November 2017 to October 2018, this retrospective multi-center study was conducted in 11 hospitals in China. It contained data from 281 cases who had undergone CPR and all of the subjects were divided into CHD group and non-CHD group. The general condition, duration of CPR, epinephrine doses during resuscitation, recovery of spontaneous circulation (ROSC), discharge survival rate and pediatric cerebral performance category in viable children at discharge were compared. According to whether malignant arrhythmia is the direct cause of cardiopulmonary arrest or not, children in CHD and non-CHD groups were divided into 2 subgroups: arrhythmia and non-arrhythmia, and the ROSC and survival rate to discharge were compared. Data in both groups were analyzed by t-test, chi-square analysis or ANOVA, and logistic regression were used to analyze the prognostic factors for ROSC and survival to discharge after cardiac arrest (CA). Results: The incidence of CA in PICU was 3.2% (372/11 588), and the implementation rate of CPR was 75.5% (281/372). There were 144 males and 137 females with median age of 32.8 (5.6, 42.7) months in all 281 CPA cases who received CPR. CHD group had 56 cases while non-CHD had 225 cases, with the percentage of 19.9% (56/281) and 80.1% (225/281) respectively. The proportion of female in CHD group was 60.7% (34/56) which was higher than that in non-CHD group (45.8%, 103/225) (χ²=4.00, P=0.045). There were no differences in ROSC and rate of survival to discharge between the two groups (P>0.05). The ROSC rate of children with arthythmid in CHD group was 70.0% (28/40), higher than 6/16 for non-arrhythmic children (χ²=5.06, P=0.024). At discharge, the pediatric cerebral performance category scores (1-3 scores) of CHD and non-CHD child were 50.9% (26/51) and 44.9% (92/205) respectively. Logistic regression analysis indicated that the independent prognostic factors of ROSC and survival to discharge in children with CHD were CPR duration (odds ratio (OR)=0.95, 0.97; 95%CI: 0.92~0.97, 0.95~0.99; both P<0.05) and epinephrine dosage (OR=0.87 and 0.79, 95%CI: 0.76-1.00 and 0.69-0.89, respectively; both P<0.05). Conclusions: There is no difference between CHD and non-CHD children in ROSC and survival rate of survival to discharge was low. The epinephrine dosage and the duration of CPR are related to the ROSC and survival to discharge of children with CHD.

Nano-Sized Niobium Tungsten Oxide Anode for Advanced Fast-Charge Lithium-Ion Batteries

The further demand for electric vehicles and smart grids prompts that the comprehensive function of lithium-ion batteries (LIBs) has been improved greatly. However, due to sluggish Li⁺ diffusion rate, thermal runway and volume expansion, the commercial graphite as an important part of LIBs is not suitable for fast-charging. Herein, nano-sized Nb₁₄ W₃ O₄₄ blocks are effectively synthesized as a fast-charge anode material. The nano-sized structure provides shorter Li⁺ diffusion pathway in the solid phase than micro-sized materials by several orders of magnitude, corresponding to accelerating the Li⁺ diffusion rate, which is beneficial for fast-charge characteristics. Consequently, Nb₁₄ W₃ O₄₄ displays excellent long-term cycling life (135 mAh g^-1 over 1000 cycles at 10 C) and rate capability at ultra-high current density (≈103.9 mAh g^-1 , 100 C) in half-cells. In situ X-ray diffraction and Raman combined with scanning electron microscopy clearly confirms the stability of crystal and microstructure. Furthermore, the fabricated Nb₁₄ W₃ O₄₄ ||LiFePO₄ full cells exhibit a remarkable power density and demonstrate a reversible specific capacity. The pouch cell delivers long cycling life (the capacity retention is as high as 96.6% at 10 C after 5000 cycles) and high-safety performance. Therefore, nano-sized Nb₁₄ W₃ O₄₄ could be recognized as a promising fast-charge anode toward next-generation practical LIBs.

[The value of myocardial work in detecting the reduction of left ventricular global systolic function in acute myocardial infarction patients with preserved ejection fraction]

Objective: To investigate the diagnosis value of myocardial work (MW) in evaluating left ventricular global systolic function among acute myocardial infarction (AMI) patients with preserved ejection fraction (LVEF). Methods: This study was a diagnostic trial in a prospective case-control design. AMI patients with preserved LVEF were enrolled as AMI(LVEF>50%) group and age and sex-matched healthy individuals undergoing healthy checkup in our hospital were collected as control group. Two-dimensional dynamic images, including standard apical two-chamber, long-axis and four-chamber views in 3 consecutive cardiac cycles were acquired. General clinical data, routine echocardiography and myocardial work parameters were obtained from all subjects. The indices were compared between the two groups. Intra-observer and inter-observer repeatability of myocardial work parameters were evaluated by intra-group correlation coefficient (ICC). Receiver operator characteristic (ROC) curve was used to determine the diagnostic value of global constructive work (GCW), global wasted work (GWW), global work efficiency (GWE) and global work index (GWI) on the reduction of left ventricular global systolic function in AMI(LVEF>50%) group. Results: There were 30 patients in AMI(LVEF>50%) group, the age was (67.3±9.7)years, and 14 cases were female(46.7%). Thirty participants were included in the control group, the age was (68.1±8.6)years, and 12 cases were female (40.0%). Compared with the control group, left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), interventricular septum thickness (IVSD), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), peak early diastolic velocity of mitral orifice/tissue Doppler velocity of posterior mitral annulus (E/e), left ventricular mass (LVM), left ventricular mass index (LVMI) were significantly higher, while E and e values were significantly lower in AMI (LVEF>50%) group (all P<0.05). Compared with the control group, GCW ((1 145.9±440.1)mmHg% (1 mmHg=0.133 kPa) vs. (1 425.7±355.4)mmHg%), GWE ((80.9±9.5)% vs. (87.3±5.5)%), GWI ((1 001.3±416.2)mmHg% vs. (1 247.6±341.7)mmHg%) and the absolute value of long axis integral strain (GLS) ((8.5±3.4)% vs. (11.4±3.7)%) were significantly lower, while peak strain dispersion(PSD)((101.3±66.4)ms vs. (74.7±31.9)ms) was significantly higher in AMI(LVEF>50%) group (P all<0 05). There was no significant difference in GWW((177.2±71.1)mmHg% vs. (155.7±64.6)mmHg%) between the two groups (P>0.05). The reproducibility of GCW, GWW, GWE and GWI within and between observers were satisfactory (all ICC>0.75). ROC curve analysis showed that all four parameters, GCW, GWW, GWE, and GWI, could be used for the diagnosis of reduced left ventricular systolic function in patients with AMI (LVEF>50%), and their areas under the ROC curve were 0.896,0.929,0.808,0.862. Conclusion: Myocardial work assessment is valuable on diagnosing left ventricular global systolic function reduction in AMI patients with preserved LVEF.

Resveratrol protects renal damages induced by periodontitis via preventing mitochondrial dysfunction in rats

OBJECTIVES

Periodontitis is closely associated with kidney disease and reactive oxygen species (ROS) involvement. Mitochondria are the primary source of both endogenous ROS and renal energy. We investigated whether resveratrol (RSV) prevents renal injury and mitochondrial dysfunction in periodontitis rats.

METHODS

Thirty male Wistar rats were divided into control, experimental periodontitis (Ep), and Ep-RSV groups. To induce periodontitis, a steel ligature was placed on the cervix of the bilateral first maxillary molars. RSV (50 mg/kg/d) to the Ep-RSV group and vehicle to the Ep and control groups were gavaged. After 8 weeks, alveolar bone loss, pocket depth, gingival blood index, and tooth mobility were assessed. Oxidative stress parameters, mitochondrial structure, mitochondrial membrane potential (MMP), mitochondrial ROS, adenosine triphosphate (ATP), sirtuin 1 (SIRT1), and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) were analysed in renal. Renal function and histology were also evaluated.

RESULTS

Compared with the control group, the Ep group showed renal structural destruction, elevated oxidative stress levels, mitochondrial structure destruction, MMP loss, mitochondrial ROS accumulation, ATP reduction, and decreased SIRT1 and PGC-1α levels. RSV prevented these destruction (p < .05). However, there was no significant impairment in renal function (p > .05).

CONCLUSIONS

Periodontitis induced mitochondrial dysfunction in renal tissues. Resveratrol exerts a preventive effect on periodontitis-induced kidney injury by preventing mitochondrial dysfunction.

Engineering Macrophages via Nanotechnology and Genetic Manipulation for Cancer Therapy

Macrophages play critical roles in tumor progression. In the tumor microenvironment, macrophages display highly diverse phenotypes and may perform antitumorigenic or protumorigenic functions in a context-dependent manner. Recent studies have shown that macrophages can be engineered to transport drug nanoparticles (NPs) to tumor sites in a targeted manner, thereby exerting significant anticancer effects. In addition, macrophages engineered to express chimeric antigen receptors (CARs) were shown to actively migrate to tumor sites and eliminate tumor cells through phagocytosis. Importantly, after reaching tumor sites, these engineered macrophages can significantly change the otherwise immune-suppressive tumor microenvironment and thereby enhance T cell-mediated anticancer immune responses. In this review, we first introduce the multifaceted activities of macrophages and the principles of nanotechnology in cancer therapy and then elaborate on macrophage engineering via nanotechnology or genetic approaches and discuss the effects, mechanisms, and limitations of such engineered macrophages, with a focus on using live macrophages as carriers to actively deliver NP drugs to tumor sites. Several new directions in macrophage engineering are reviewed, such as transporting NP drugs through macrophage cell membranes or extracellular vesicles, reprogramming tumor-associated macrophages (TAMs) by nanotechnology, and engineering macrophages with CARs. Finally, we discuss the possibility of combining engineered macrophages and other treatments to improve outcomes in cancer therapy.

Periodontal ligament stem cells promote polarization of M2 macrophages

Macrophages are widely distributed in a variety of tissues, and the different state of macrophages polarization is closely related to the occurrence, development, and prognosis of inflammation, including periodontitis, a chronic inflammatory disease leading to tooth loss worldwide. Periodontal ligament stem cells (PDLSCs) play a key role in immune regulation and periodontal tissues regeneration, contributing to cell-based therapy of periodontitis. However, the interactions between PDLSCs and macrophages are still elusive. The purpose of present study is to investigate the effect of PDLSCs conditioned medium (PDLSCs-CM) on the macrophage polarization and the possible mechanism. PDLSCs were isolated using tissue explant methods and characterized via multipotent differentiation test and examination of expression profiles of mesenchymal stem cells (MSCs) markers. The supernatant of PDLSCs was collected, centrifuged, filtered, and used as PDLSCs-CM. Then, PDLSCs-CM was cocultured with M0 macrophages or IL-4- and IL-13-induced M2 macrophages. The level of surface markers of M1/M2 macrophages and production of several proinflammatory or anti-inflammatory factors were evaluated by flow cytometric analysis and enzyme-linked immunosorbent assay, respectively. The associated genes and proteins involved in the JNK pathway were investigated to explore the potential mechanism that may regulate PDLSCs-CM-mediated macrophage polarization. PDLSCs expressed MSCs markers, including STRO-1, CD146, CD90, and CD73, and were negative for CD34 and CD45, could undergo osteogenic and adipogenic differentiation when cultured in defined medium. After incubation with PDLSCs-CM, no significant increase of CD80+ and HLA-DR+ M1 macrophages was shown while evaluated CD209+ and CD206+ M2 macrophages were observed. In addition, the levels of anti-inflammatory factors such as IL-10, TGF-β, and CCL18 were increased instead of proinflammatory factors such as IL-1β, TNF-α with PDLSC-CM treatment. There was a decrease of JNK expression on M0 macrophages by qRT-PCR analysis and an increase of protein phosphorylation on M0 macrophages after incubation with PDLSCs-CM. Furthermore, as for the enhancement of IL-4- and IL-13-mediated M2 polarization by PDLSCs-CM, the mRNA level of JNK decreased, and the protein phosphorylation level of JNK increased. In addition, the treatment of JNK pathway inhibitor, SP600125, could inhibit the expression and secretion level of anti-inflammatory factor such as IL-10 in M2 polarization induced by PDLSCs-CM. Collectively, PDLSCs were able to induce M2 macrophage polarization instead of M1 polarization, and capable of enhancing M2 macrophage polarization induced by IL-4 and IL-13. The JNK pathway was involved in the promotion of M2 macrophage polarization.