All-solid-state 3-µm single-frequency Er:CaF2 laser with a stable and switchable wavelength.

We have demonstrated a 3-µm all-solid-state single-frequency laser with a stable center frequency and a switchable wavelength using the intra-cavity Fabry-Perot etalon method. Experimentally, the central wavelengths of the laser for the single-longitudinal mode are 2728 and 2794 nm, with maximum output powers of 268 and 440 mW, respectively. The corresponding single-longitudinal mode linewidths are 25 and 11 MHz. In particular, the central wavelengths of the single-longitudinal mode laser remain almost constant as the incident pump power increases. To the best of our knowledge, this study represents the first instance of using a laser diode to directly pump Er:CaF2 block single crystals for single-frequency lasers in the 3 µm region. Additionally, it achieves the highest output power of a 3-µm all-solid-state single-longitudinal mode.

Telomere dysfunction alters intestinal stem cell dynamics to promote cancer.

Telomere dynamics are linked to aging hallmarks, and age-associated telomere loss fuels the development of epithelial cancers. In Apc-mutant mice, the onset of DNA damage associated with telomere dysfunction has been shown to accelerate adenoma initiation via unknown mechanisms. Here, we observed that Apc-mutant mice engineered to experience telomere dysfunction show accelerated adenoma formation resulting from augmented cell competition and clonal expansion. Mechanistically, telomere dysfunction induces the repression of EZH2, resulting in the derepression of Wnt antagonists, which causes the differentiation of adjacent stem cells and a relative growth advantage to Apc-deficient telomere dysfunctional cells. Correspondingly, in this mouse model, GSK3ß inhibition countered the actions of Wnt antagonists on intestinal stem cells, resulting in impaired adenoma formation of telomere dysfunctional Apc-mutant cells. Thus, telomere dysfunction contributes to cancer initiation through altered stem cell dynamics, identifying an interception strategy for human APC-mutant cancers with shortened telomeres.

Comparison of the gastrointestinal bacterial microbiota between dairy cows with and without mastitis.

Mastitis causes significant losses in the global dairy industry, and the health of animals has been linked to their intestinal microbiota. To better understand the relationship between gastrointestinal microbiota and mastitis in dairy cows, we collected blood, rumen fluid, and fecal samples from 23 dairy cows, including 13 cows with mastitis and 10 healthy cows. Using ELISA kit and high-throughput sequencing, we found that cows with mastitis had higher concentrations of TNF-α, IL-1, and LPS than healthy cows (p < 0.05), but no significant differences in microbiota abundance or diversity (p > 0.05). Principal coordinate analysis (PCOA) revealed significant differences in rumen microbial structure between the two groups (p < 0.05), with Moryella as the signature for rumen in cows with mastitis. In contrast, fecal microbial structure showed no significant differences (p > 0.05), with Aeriscardovia, Lactococcus, and Bacillus as the signature for feces in healthy cows. Furthermore, the results showed distinct microbial interaction patterns in the rumen and feces of cows with mastitis compared to healthy cows. Additionally, we observed correlations between the microbiota in both the rumen and feces of cows and blood inflammatory indicators. Our study sheds new light on the prevention of mastitis in dairy cows by highlighting the relationship between gastrointestinal microbiota and mastitis.

The endonuclease FEN1 mediates activation of STAT3 and facilitates proliferation and metastasis in breast cancer.

BACKGROUND: The metastasis accounts for most deaths from breast cancer (BRCA). Understanding the molecular mechanisms of BRCA metastasis is urgently demanded. Flap Endonuclease 1 (FEN1), a pivotal factor in DNA metabolic pathways, contributes to tumor growth and drug resistance, however, little is known about the role of FEN1 in BRCA metastasis. METHODS AND RESULTS: In this study, FEN1 expression and its clinical correlation in BRCA were investigated using bioinformatics, showing being upregulated in BRCA samples and significant relationships with tumor stage, node metastasis, and prognosis. Immunohistochemistry (IHC) staining of local BRCA cohort indicated that the ratio of high FEN1 expression in metastatic BRCA tissues rose over that in non-metastatic tissues. The assays of loss-of-function and gain-of-function showed that FEN1 enhanced BRCA cell proliferation, migration, invasion, xenograft growth as well as lung metastasis. It was further found that FEN1 promoted the aggressive behaviors of BRCA cells via Signal Transducer and Activator of Transcription 3 (STAT3) activation. Specifically, the STAT3 inhibitor Stattic thwarted the FEN1-induced enhancement of migration and invasion, while the activator IL-6 rescued the decreased migration and invasion caused by FEN1 knockdown. Additionally, overexpression of FEN1 rescued the inhibitory effect of nuclear factor-κB (NF-κB) inhibitor BAY117082 on phosphorylated STAT3. Simultaneously, the knockdown of FEN1 attenuated the phosphorylation of STAT3 promoted by the NF-κB activator tumor necrosis factor α (TNF-α). CONCLUSIONS: These results indicate a novel mechanism that NF-κB-driven FEN1 contributes to promoting BRCA growth and metastasis by STAT3 activation.

Pulsed Ho:YLF laser intra-cavity pumped by a diode-pumped Q-switched Tm:YAP laser.

We reported an intra-cavity pumped Q-switched laser with dual-wavelength synchronous output at 2066.7 nm and 1940nm. Ho:YLF crystal was pumped by a self-Q-switched Tm:YAP laser, which was served as both a gain medium and a saturable absorber simultaneously. For Ho:YLF laser, under 11.4-W incident pump power, a stable pulse laser was achieved at 2066.7 nm with the highest peak power of 69.65 W and the pulse repetition rate of 42.14 kHz. Under the same incident pump power, the highest peak power and pulse repetition rate of Tm:YAP laser were 17.85 W and 50.82 kHz, corresponding to the central wavelength of 1940nm. These results suggested that Q-switching without additional absorber element were effective way to obtain high-efficiency and compact 2.1 µm pulsed laser.

AMPFLDAP: Adaptive Message Passing and Feature Fusion on Heterogeneous Network for LncRNA-Disease Associations Prediction.

Exploration of the intricate connections between long noncoding RNA (lncRNA) and diseases, referred to as lncRNA-disease associations (LDAs), plays a pivotal and indispensable role in unraveling the underlying molecular mechanisms of diseases and devising practical treatment approaches. It is imperative to employ computational methods for predicting lncRNA-disease associations to circumvent the need for superfluous experimental endeavors. Graph-based learning models have gained substantial popularity in predicting these associations, primarily because of their capacity to leverage node attributes and relationships within the network. Nevertheless, there remains much room for enhancing the performance of these techniques by incorporating and harmonizing the node attributes more effectively. In this context, we introduce a novel model, i.e., Adaptive Message Passing and Feature Fusion (AMPFLDAP), for forecasting lncRNA-disease associations within a heterogeneous network. Firstly, we constructed a heterogeneous network involving lncRNA, microRNA (miRNA), and diseases based on established associations and employing Gaussian interaction profile kernel similarity as a measure. Then, an adaptive topological message passing mechanism is suggested to address the information aggregation for heterogeneous networks. The topological features of nodes in the heterogeneous network were extracted based on the adaptive topological message passing mechanism. Moreover, an attention mechanism is applied to integrate both topological and semantic information to achieve the multimodal features of biomolecules, which are further used to predict potential LDAs. The experimental results demonstrated that the performance of the proposed AMPFLDAP is superior to seven state-of-the-art methods. Furthermore, to validate its efficacy in practical scenarios, we conducted detailed case studies involving three distinct diseases, which conclusively demonstrated AMPFLDAP's effectiveness in the prediction of LDAs.

Sub-nanometer Mono-Layered Metal-Organic Frameworks Nanosheets for Simulated Flue Gas Photoreduction.

The dilemma between the thickness and accessible active site triggers the design of porous crystalline materials with mono-layered structure for advanced photo-catalysis applications. Here, we report a kind of sub-nanometer mono-layered nanosheets (Co-MOF MNSs) through the exfoliation of a specifically designed Co3 cluster-based metal-organic frameworks (MOFs). The sub-nanometer thickness and inherent light-sensitivity endow Co-MOF MNSs with fully exposed Janus Co3 sites that can selectively photo-reduce CO2 into formic acid under simulated flue gas. Notably, the production efficiency of formic acid by Co-MOF MNSs (0.85 mmol g-1 h-1) is ∼13 times higher than that of bulk counterpart (0.065 mmol g-1 h-1) under simulated flue gas atmosphere, which is highest in reported works up to date. Theoretical calculations prove that the exposed Janus Co3 sites with simultaneously available sites possess higher activity when compared with single Co site, validating the importance of mono-layered nanosheet morphology. Our results might facilitate the development of functional nanosheet materials for CO2 photo-reduction in potential flue gas treatment. This article is protected by copyright. All rights reserved.

Tuning Spin-Polarized Lifetime at High Carrier Density through Deformation Potential in Dion-Jacobson-Phase Perovskites.

The control of spin relaxation mechanisms is of great importance for spintronics applications as well as for fundamental studies. Layered metal-halide perovskites represent an emerging class of semiconductors with rich optical spin physics, showing potential for spintronic applications. However, a major hurdle arises in layered metal-halide perovskites with strong spin-orbit coupling, where the spin lifetime becomes extremely short due to D'yakonov-Perel' scattering and Bir-Aronov-Pikus at high carrier density. Using the circularly polarized pump-probe transient reflection technique, we experimentally reveal the important scattering for spin relaxation beyond the electron-hole exchange strength in the Dion-Jacobson (DJ)-type 2D perovskites (3AMP)(MA)n-1PbnI3n+1 [3AMP = 3-(aminomethyl)piperidinium, n = 1-4]. Despite a more than 10-fold increase in carrier concentration, the spin lifetimes for n = 3 and 4 are effectively maintained. We reveal neutral impurity and polar optical phonon scatterings as significant contributors to the momentum relaxation rate. Furthermore, we show that more octahedral distortions induce a larger deformation potential which is reflected on the acoustic phonon properties. Coherent acoustic phonon analysis indicates that the polaronic effect is crucial in achieving control over the scattering mechanism and ensuring spin lifetime protection, highlighting the potential of DJ-phase perovskites for spintronic applications.

Non-Photochemical Origin of Selectivity Difference between Light and Dark Catalytic Conditions.

The interest in introducing light into heterogeneous catalysis is driven not only by the urgent need of replacing fossil energy but also by the promise of controlling product selectivity by light. The product selectivity differences observed in recent studies between light and dark reactions are often attributed to photochemical effects. Here, we report the discovery of a non-photochemical origin of selectivity difference, at essentially the same CO2 conversion rate, between photothermal and thermal CO2 hydrogenation reactions over a Ru/TiO2-x catalyst. While the presence of the photochemical effect from ultraviolet light is confirmed, it merely enhances the catalytic activity. Systematic investigation reveals that the gradual formation of an adsorbate-mediated strong metal-support interaction under catalytic conditions is responsible for the variation in the catalytic selectivity. We demonstrate that differences in product selectivity under light/dark reactions do not necessarily originate from photochemical effects. Our study refines the basis for determining photochemical effects and highlights the importance of excluding non-photochemical effects in mechanistic studies of light-controlled product selectivity.

The Predictive Value of Serum F-actin on the Severity and Early Neurological Deterioration of Acute Ischemic Stroke: PREDICTIVE VALUE OF F-ACTIN IN STROKE.

BACKGROUND: F-actin is involved in the progression of ischemic stroke and is associated with the disruption of the blood-brain barrier. In this article, we evaluated serum F-actin as a biomarker in stroke severity and early neurological deterioration (END) in acute ischemic stroke. METHODS: In this study, serum F-actin was measured in consecutively collected 140 AIS patients and 144 healthy controls matched in gender and age by ELISA. Early neurological deterioration (END) was defined as the deterioration of neurological dysfunction within 72 hours of admission, with an increase of ≥ 4 points in the NIHSS score. Severe stroke was defined as a NIHSS score>8 at admission. RESULTS: The serum F-actin level in AIS was significantly higher than healthy controls (p = 0.041). In large-artery atherosclerosis stroke and cardioembolic stroke, serum F-actin were significantly higher than that in small artery occlusion stroke (padjust = 0.019, padjust<0.001, respectively).F-actin level above the critical value (>1.37ug/L) was significantly associated with severe stroke (OR, 3.015; 95%CI, 1.014-8.963; p = 0.047) . In addition, elevated level of F-actin was significantly associated with END (OR, 1.323; 95% CI, 1.001-1.747, P = 0.049). When the level of F-actin was above the critical value (>2.17ug/L), its association with END remained significant (OR, 6.303; 95%CI, 2.160-18.394; p<0.001) . CONCLUSION: F-actin is an important blood biomarker in the early stage of AIS, and high levels of F-actin are valuable in determining the severity of stroke and predicting early neurological deterioration.

Apatinib beyond first progression is associated with prolonged overall survival in patients with advanced breast cancer: Results from an observational study.

In the present study, the efficacy and safety of a low dose of apatinib in the treatment of patients with advanced breast cancer (ABC) in a real-world setting were assessed, the impact of continuous anti-angiogenic therapy beyond progression was determined and the factors associated with efficacy were evaluated. A total of 63 patients with ABC who were treated with apatinib and for whom several lines of treatment had failed were retrospectively analyzed in Tangshan People's Hospital (Tangshan, China) between January 2016 and October 2022. Apatinib was administered orally combined with chemotherapy, endocrine therapy, targeted therapy or monotherapy at a dose of 250 mg per day. Apatinib administration was continued in certain patients beyond first progressive disease (PD), and these patients were defined as the continued anti-angiogenic treatment beyond first progression (CABF) group, while those who discontinued apatinib were defined as the non-CABF group. In the evaluation of the first efficacy, the objective response rate was 33.3%. A total of 26 patients continued to receive apatinib post-first PD and were allocated to the CABF group. The median overall survival (OS) time of the 63 patients was 16 months. Log-rank univariate analysis revealed that the OS time was significantly associated with molecular subtype (P=0.014), CABF (P=0.004), and the neutrophil-to-lymphocyte ratio (NLR) (P=0.011). Multivariate Cox regression analysis revealed that being in the non-CABF group and a high NLR were independent risk factors for lower OS time (P=0.017 and P=0.041, respectively). These results support the continued administration of low-dose apatinib beyond progression and the use of NLR as an easily accessible prognostic marker in patients with ABC treated with apatinib.

Interaction of acetylcholine and oxytocin neuromodulation in the hippocampus.

A postulated role of subcortical neuromodulators is to control brain states. Mechanisms by which different neuromodulators compete or cooperate at various temporal scales remain an open question. We investigated the interaction of acetylcholine (ACh) and oxytocin (OXT) at slow and fast timescales during various brain states. Although these neuromodulators fluctuated in parallel during NREM packets, transitions from NREM to REM were characterized by a surge of ACh but a continued decrease of OXT. OXT signaling lagged behind ACh. High ACh was correlated with population synchrony and gamma oscillations during active waking, whereas minimum ACh predicts sharp-wave ripples (SPW-Rs). Optogenetic control of ACh and OXT neurons confirmed the active role of these neuromodulators in the observed correlations. Synchronous hippocampal activity consistently reduced OXT activity, whereas inactivation of the lateral septum-hypothalamus path attenuated this effect. Our findings demonstrate how cooperative actions of these neuromodulators allow target circuits to perform specific functions.

Identification and Analysis of the MIR399 Gene Family in Grapevine Reveal Their Potential Functions in Abiotic Stress.

MiR399 plays an important role in plant growth and development. The objective of the present study was to elucidate the evolutionary characteristics of the MIR399 gene family in grapevine and investigate its role in stress response. To comprehensively investigate the functions of miR399 in grapevine, nine members of the Vvi-MIR399 family were identified based on the genome, using a miRBase database search, located on four chromosomes (Chr 2, Chr 10, Chr 15, and Chr 16). The lengths of the Vvi-miR399 precursor sequences ranged from 82 to 122 nt and they formed stable stem-loop structures, indicating that they could produce microRNAs (miRNAs). Furthermore, our results suggested that the 2 to 20 nt region of miR399 mature sequences were relatively conserved among family members. Phylogenetic analysis revealed that the Vvi-MIR399 members of dicots (Arabidopsis, tomato, and sweet orange) and monocots (rice and grapevine) could be divided into three clades, and most of the Vvi-MIR399s were closely related to sweet orange in dicots. Promoter analysis of Vvi-MIR399s showed that the majority of the predicted cis-elements were related to stress response. A total of 66.7% (6/9) of the Vvi-MIR399 promoters harbored drought, GA, and SA response elements, and 44.4% (4/9) of the Vvi-MIRR399 promoters also presented elements involved in ABA and MeJA response. The expression trend of Vvi-MIR399s was consistent in different tissues, with the lowest expression level in mature and young fruits and the highest expression level in stems and young leaves. However, nine Vvi-MIR399s and four target genes showed different expression patterns when exposed to low light, high light, heat, cold, drought, and salt stress. Interestingly, a putative target of Vvi-MIR399 targeted multiple genes; for example, seven Vvi-MIR399s simultaneously targeted VIT_213s0067g03280.1. Furthermore, overexpression of Vvi_MIR399e and Vvi_MIR399f in Arabidopsis enhanced tolerance to drought compared with wild-type (WT). In contrast, the survival rate of Vvi_MIR399d-overexpressed plants were zero after drought stress. In conclusion, Vvi-MIR399e and Vvi-MIR399f, which are related to drought tolerance in grapevine, provide candidate genes for future drought resistance breeding.

Melatonin Alleviates BPA-Induced Testicular Apoptosis and Endoplasmic Reticulum Stress.

BACKGROUND: The impact of melatonin on bisphenol A (BPA)-induced testicular apoptosis and endoplasmic reticulum (ER) stress was explored. METHODS: The mice received BPA (50 mg/kg) by gavage for 30 days while being injected with 20 mg/kg melatonin. Protein expressions were detected with western blotting. The Terminal Deoxynucleotidyl Transferase dUTP Nick End Labeling (TUNEL) assay measured testicular cell apoptosis. Testosterone was quantified by employing enzyme-linked immunosorbent assay (ELISA). RESULTS: Melatonin promoted the development of seminiferous tubules, restored the orderly arrangement of the germ cells, and increased epithelial layers in the seminiferous tubules in BPA-treated mice. Moreover, in BPA-treated mouse testicular cells, melatonin markedly upregulated melatonin receptor 1A (MTNR1A) and melatonin Receptor 2 (MTNR2) expressions while downregulating ER molecular chaperones glucose-regulated protein 78 (GRP78) and glucose-regulated protein 94 (GRP94). Furthermore, it decreased p-PERK, p-IRE1, and ATF6α, as well as the apoptotic proteins cysteine-containing aspartate-specific proteases-12 (caspase-12) and cleaved cysteine-containing aspartate-specific proteases-3 (cleaved caspase-3), causing the suppression of testicular cell apoptosis. Additionally, melatonin increased the levels of cytochrome P450 17α-hydroxylase/20-lyase (CYP17A1), 17ß-hydroxysteroid dehydrogenase 3 (17ß-HSD3), and 3ß-hydroxysteroid dehydrogenase 4 (3ß-HSD4), in the ER, and elevated testosterone levels in testicular tissue. CONCLUSIONS: Melatonin can significantly alleviate testicular apoptosis and ER stress induced by BPA, which is because of the upregulation of melatonin receptor expression in testicular cells, inhibition of ER stress-related pathways, and enhancement of testosterone synthesis.

Differentiation of confluent hepatic fibrosis and infiltrative hepatocellular carcinoma on MR imaging.

BACKGROUND: To identify reliable magnetic resonance imaging (MRI) features that can differentiate confluent fibrosis (CF) from infiltrative hepatocellular carcinoma (HCC). METHODS: A retrospective analysis was conducted on Twenty CF patients and 28 infiltrative HCC patients who underwent upper abdomen MRI scans. The imaging features of lesions were analyzed, and the apparent diffusion coefficient (ADC) of lesions were measured. Accuracy, sensitivity and specificity for the diagnosis of CF were calculated for each category individually and combined. RESULTS: Compared to infiltrative HCC, hepatic capsular retraction at the site of lesion, hepatic volume loss at the site of lesion and "nodular surround sign" were more common in patients with CF (all P < 0.001). Hepatic volume loss at the site of lesion, no or mild enhancement in arterial phase, and hyper-enhancing in delayed phase to the background parenchyma showed superior diagnostic accuracy (83.3%, 85.4%, 97.9%, respectively). When the lesion exhibited hepatic volume loss at the site of lesion or no or mild enhancement in arterial phase or hyper-enhancing in delayed phase, a sensitivity of 100.0% for the diagnosis of CF was achieved. When the lesion was positive for any two of three categories, or positive for all three categories, a specificity of 100.0% was achieved. The ADC values of CF were higher than those of infiltrative HCC (P < 0.001). CONCLUSION: The combination of the hepatic volume loss at the site of lesion, no or mild enhancement in arterial phase, and hyper-enhancing in delayed phase to the background parenchyma can be considered reliable MR features for the diagnosis of CF, as they allow differentiation from infiltrative HCC.

Purification and Structural Characterization of Polysaccharides from Polygonum multiflorum Thunb. and Their Immunostimulatory Activity in RAW264.7 Cells.

Polygonum multiflorum Thunb. (PM) and derived products are broadly utilized in Chinese traditional medicine. According to our previous research, PM mostly contains polysaccharides, which display a wide range of biological activities. Two water-soluble polysaccharides (PMPs-1 and PMPs-2) were obtained from PM by DEAE-Cellulose and Sephadex G-100 column chromatography. Colorimetry, HPGPC-MALLS-RID, HPLC-PDA, methylation, FT-IR, NMR, and SEM were used to characterize these polysaccharides. PMPs-1 and PMPs-2 had average molecular weights of 255.5 and 55.7 kDa, respectively. PMPs-1 consisted of Man, Glc, Gal, and Ara at 0.9:78.6:1.0:1.6 and was a glucan with → 4)-Glcp-(1 → as a backbone. Meanwhile, PMPs-2, an acidic polysaccharide, comprised Rha, GalA, Glc, Gal, and Ara at 3.2:20.3:2.7:1.0:8.3. PMPs-1 and PMPs-2 significantly improved the proliferation of RAW 264.7 cells and induced NO, TNF-α, and IL-6 release. This study reveals that these two polysaccharides can be explored as novel immunomodulators and provide a basis for further development of PM in food and pharmaceutical industries.

Early warning on safety risk of highly aggregated tourist crowds based on VGGT-Count network model.

In the era of mass tourism, more and more people are attracted by internet-famous site. With people's demand for travel surged, tourists are getting together in one scenic spot with doubling numbers, which easily leads to high concentration of tourists with uncontrollable security risks. It needs to be highly valued by the tourism department. Monitoring and issuing warnings for crowd density in scenic areas with Highly Aggregated Tourist Crowds (HATCs) is an urgent challenge that needs to be addressed. In this paper, Highly Aggregated Tourist Crowds is taken as the research objective, and a VGGT-Count network model is proposed to forecast the density of HATCs. The experimental outcomes demonstrated a substantial improvement in counting accuracy for the ShanghaiTech B and UCF-QNRF datasets. Furthermore, the model allows for real-time monitoring of tourist attractions, enabling advanced prediction of high concentrations in scenic areas. This timely information can alert relevant authorities to implement preventive measures such as crowd control and flow regulation, thereby minimizing safety hazards.

A unique circulating microRNA pairs signature serves as a superior tool for early diagnosis of pan-cancer.

Cancer remains a major burden globally and the critical role of early diagnosis is self-evident. Although various miRNA-based signatures have been developed in past decades, clinical utilization is limited due to a lack of precise cutoff value. Here, we innovatively developed a signature based on pairwise expression of miRNAs (miRPs) for pan-cancer diagnosis using machine learning approach. We analyzed miRNA spectrum of 15832 patients, who were divided into training, validation, test, and external test sets, with 13 different cancers from 10 cohorts. Five different machine-learning (ML) algorithms (XGBoost, SVM, RandomForest, LASSO, and Logistic) were adopted for signature construction. The best ML algorithm and the optimal number of miRPs included were identified using area under the curve (AUC) and youden index in validation set. The AUC of the best model was compared to previously published 25 signatures. Overall, Random Forest approach including 31 miRPs (31-miRP) was developed, proving highly efficient in cancer diagnosis across different datasets and cancer types (AUC range: 0.980-1.000). Regarding diagnosis of cancers at early stage, 31-miRP also exhibited high capacities, with AUC ranging from 0.961 to 0.998. Moreover, 31-miRP exhibited advantages in differentiating cancers from normal tissues (AUC range: 0.976-0.998) as well as differentiating cancers from corresponding benign lesions. Encouragingly, comparing to previously published 25 different signatures, 31-miRP also demonstrated clear advantages. In conclusion, 31-miRP acts as a powerful model for cancer diagnosis, characterized by high specificity and sensitivity as well as a clear cutoff value, thereby holding potential as a reliable tool for cancer diagnosis at early stage.