Lindenane sesquiterpenoid dimers from Chloranthus japonicus improve LDL uptake by regulating PCSK9 and LDLR.

UPLC-TOF-MS/MDF directed phytochemical research of Chloranthus japonicus led to the isolation of 46 lindenane sesquiterpenoid dimers, which included 13 new analogs. Their structures with absolute configurations were elucidated by analysis of spectroscopic data. Fourteen compounds with ester chains significantly decreased PCSK9 protein level in medium of HepG2 cells, especially for compounds 14 and 29 (5 µM) with inhibition rates of 69.0% and 72.8%, respectively. Compound 14 in HepG2 cells was evaluated via DiI-LDL uptake assays and found to increase LDL uptake by upregulating LDLR mRNA and protein level. Meanwhile, 14 decreased the secretion of PCSK9 protein in medium and downregulated intracellular PCSK9 protein and mRNA level. The discovery of these natural small molecule compounds provides a novel structure basis for design PCSK9 regulators, making them a promising lead for development of new lipid-lowering agents.

Association of four gene polymorphisms in Chinese Guangxi population with diabetic retinopathy in type 2 diabetic patients.

BACKGROUND: Diabetic retinopathy (DR) is one of the most common chronic microvascular complications of diabetes. Many studies have suggested that genetic factors are important in the context of DR. This study evaluated the associations of GWAS (Genome-wide association study) -identified DR-associated SNPs in a Chinese population in Guangxi Province with type 2 diabetes mellitus (T2DM). METHODS: A total of 386 hospitalized T2DM patients without proliferative diabetic retinopathy (PDR) and 316 hospitalized T2DM patients with PDR were included in this case-control study. Four tag SNPs, including rs1800896 in the IL-10 gene, rs2010963 in the VEGFA gene, rs2070600 in the RAGE gene and rs2910164 in the miR-146a gene, were examined using KASP (kompetitive allele specific PCR) genotyping assays. RESULTS: There were no significant differences in the genotype or allele frequencies of the miR-146a polymorphism (rs2910164) between subjects with PDR and those without DR. The TC genotype of rs1800896 was determined to be associated with an increased risk of PDR (the odds ratio (OR) was 2.366, with a 95% confidence interval (CI) ranging from 1.144 to 4.894). The CG genotypes of rs2010963 was associated with an decreased risk of PDR (the OR was 0.588, with a 95% CI ranging from 0.366 to 0.946). Regarding rs2070600, 2 genotypes (TT and CT) were associated with a decreased risk of PDR (the OR of the TT genotype was 0.180, with a 95% CI ranging from 0.037 to 0.872, and the OR of the CT genotype was 0.448, with a 95% CI ranging from 0.266 to 0.753). CONCLUSIONS: The rs1800896 polymorphisms in the IL-10 gene, rs2010963 in the VEGFA gene and rs2070600 in the RAGE gene are associated with the risk of PDR in the Han Chinese population of Guangxi Province. Our findings provide suggestive evidence that these polymorphisms may be involved in the pathogenesis of PDR and should be investigated further.

[Effect of Polygonum multiflorum-Andrographis paniculata intercropping system on rhizosphere soil actinomycetes community structure and diversity of P. multiflorum].

To investigate the effect of Polygonum multiflorum-Andrographis paniculata intercropping system on rhizosphere soil actinomycetes of P. multiflorum, the community structure and diversity of soil actinomycetes were studied by using the original soil as the control group and the rhizosphere soil actinomycetes communities of P. multiflorum under monoculture and intercropping systems as the experimental group. In this study 655 221 effective sequences were obtained with an average length of 408 bp. OTU coverage and rarefaction curve showed that the sequencing could represent the real situation of soil actinomycetes. According to the results of alpha diversity analysis, the diversity soil actinomycetes varied as follows: original soil>intercropping soil>monoculture soil. The soil actinomycetes community structure and the relative abundance of dominant genera were significantly changed by both monoculture and intercropping, especially monoculture. OTU clustering and PCA analysis of soil samples showed that all the soil samples were divided into three distinct groups and the original soil was more similar to intercropping soil. In addition, intercropping increased the relative abundance of some beneficial actinomyces, such as Kitasatospora and Mycobacterium, which was beneficial to maintain soil health and reduce the occurrence of soil-borne diseases. The results show that, P. multiflorum-A. paniculata intercropping reduced the change of community structure and the decrease of diversity of soil actinomycetes caused by P. multiflorum monoculture, and made the actinomycete community in rhizosphere soil of P. multiflorum close to the original soil.

Mesopore Connectivity Improving Aerosol-Assisted Synthesis of Mesoporous Alumina Powders with High Surface Area.

Considering the closed packing of supramolecular mediated cage-type (spherical) mesopores inside spherical particles that are typically obtained by the aerosol-assisted process, uniform mesopores cannot be packed so periodically and then the mesopores are less connected and/or occasionally isolated, leading to the formation of low-surface-area mesoporous particles. In this study, we proposed the controlled swelling of such cage-type mesopores for improving their connectivity. Actually, we succeeded in preparing high-surface-area mesoporous alumina powders using poly(oxyethylene)- block-poly(oxypropylene)- block-poly(oxyethylene) (EO nPO mEO n) type triblock copolymers such as Pluronic P123. The surface area of the mesoporous alumina powders was originally low (278 m2 g-1 without organic additives), which can be drastically increased up to ca. 540 m2 g-1 through the controlled welling with suitable addition of 1,3,5-trimethylbenzene and 1,3,5-triisopropylbenzene. The insight is promising for further development of the aerosol-assisted approach for recovering high-quality mesoporous powders and helpful for rational catalyst design by utilizing mesoporous alumina powders with extremely high surface area.

Synthesis and structural characteristics of high surface area TiO2 aerogels by ultrasonic-assisted sol-gel method.

TiO2 aerogel is a unique three-dimensional porous nano-particle material with the characteristics of high specific surface area and good light transmittance. In this paper, a novel method involving ultrasonic-assisted sol-gel, solvent exchange, and vacuum drying was successfully developed to synthesis the TiO2 aerogel. The morphology and properties of the prepared TiO2 aerogels were characterized by the Brunauer-Emmett-Teller theory (BET), x-ray diffraction, field-emission scanning electron microscopy, energy dispersive spectroscopy, thermogravimetric analysis-differential thermal analysis, Fourier transform infrared spectroscopy, and Raman spectroscopy. The adsorption and photocatalytic activity of TiO2 aerogels was evaluated by monitoring the degradation of Rhodamine B solution. Our results indicated that: (1) with an optimum ratio of Ti:H2O = 8:1 the BET surface area, average pore diameter, and total pore volume of TiO2 aerogel are enhanced to 563.6 m2 g-1, 3.01 nm, and 0.42 cm3 g-1, respectively; (2) the TiO2 aerogels possessed controllable crystal form depending on the thermal treatments conditions. The crystal face (101) of anatase, complete anatase, mixed state of anatase and rutile, and rutile were obtained by increasing the temperature from 200 °C-300 °C, from 400 °C-500 °C, 600 °C, and from 700 °C-1000 °C, respectively; and (3) the excellent catalytic activity of the as-prepared TiO2 aerogels for the ultraviolet photolytic degradation of Rhodamine B had attributed to the synergistic effect of adsorption and photoactivity.

Systematic Mutational Analysis of Histidine Kinase Genes in the Nosocomial Pathogen Stenotrophomonas maltophilia Identifies BfmAK System Control of Biofilm Development.

The Gram-negative bacterium Stenotrophomonas maltophilialives in diverse ecological niches. As a result of its formidable capabilities of forming biofilm and its resistance to multiple antibiotic agents, the bacterium is also a nosocomial pathogen of serious threat to the health of patients whose immune systems are suppressed or compromised. Besides the histidine kinase RpfC, the two-component signal transduction system (TCS), which is the canonical regulatory machinery used by most bacterial pathogens, has never been experimentally investigated inS. maltophilia Here, we annotated 62 putative histidine kinase genes in the S. maltophilia genome and successfully obtained 51 mutants by systematical insertional inactivation. Phenotypic characterization identified a series of mutants with deficiencies in bacterial growth, swimming motility, and biofilm development. A TCS, named here BfmA-BfmK (Smlt4209-Smlt4208), was genetically confirmed to regulate biofilm formation inS. maltophilia Together with interacting partner prediction and chromatin immunoprecipitation screens, six candidate promoter regions bound by BfmA in vivo were identified. We demonstrated that, among them, BfmA acts as a transcription factor that binds directly to the promoter regions of bfmA-bfmK and Smlt0800(acoT), a gene encoding an acyl coenzyme A thioesterase that is associated with biofilm development, and positively controls their transcription. Genome-scale mutational analyses of histidine kinase genes and functional dissection of BfmK-BfmA regulation in biofilm provide genetic information to support more in-depth studies on cellular signaling inS. maltophilia, in the context of developing novel approaches to fight this important bacterial pathogen.

[Micro-Raman Spectral Characteristics and Implication of FeS2 from Metamorphic Belt between Coal and Intrusion in Wolonghu Coal Mine of Anhui Province, China].

Some FeS2 samples among metamorphic belt between coal and intrusion from Wolonghu mine in the north of Anhui Province were retrieved to characterize the signature of Raman Spectral. The results show that, all Raman data of different samples can be divided into 3 types as Ⅰ, Ⅱ and Ⅲ according to distinct differences of in Raman mode (M), Raman shift (Δν) and scattering intensity (Ⅰ). There are five strong scattering modes including high value Eg (1.16~1.59×103), high value Ag (2.33~2.53×103) and low value Tg (0.20~0.27×103) in typeⅠand only former three modes in type Ⅱ although the value of Eg, Ag and Tg are similar between them. While there are only two modes of high value Eg about 327.6~328.8 cm-1 and low value Ag 389.0~390.1 cm-1. Our analyses indicate that type Ⅰ samples must be mixed crystal of pyrite and natural coke for the former three peaks are same to deformation and stretching vibration of Fe-[S2]2- and stretching vibration of S­S in pyrite, while the latter two are similar to the vibration of Tiny graphite crystals and stretching vibration of C­C among graphite crystal from Raman data. And typeⅡsample may be pyrite for typical pyrite Scattering peak and Type Ⅲ sample possibility are low-temperature crystalloblastic of pyrite for Marcasite spectrum features in Raman. Further analysis also showed that the formation pressure of typeⅠ and Ⅱ are the same while type Ⅲ samples formed in low pressure for Raman scattered intensity of typeⅠand Ⅱ are similar, and type Ⅲ samples is obviously lower than the former two. And the formation temperature of typeⅠ, typeⅡ and type Ⅲ significantly decreased in turn for Ag peak of them are turn to high frequency about 4.4~6.7, 4.5~8.4cm-1 respectively compared with the former. Thus，The authors' studies suggest that pyrite samples from Metamorphic coal and metamorphic zone in Wolonghu coal mine are products in high temperature, but samples from Magmatic rocks are Marcasite formed at low temperature.

[Effects on single segmental lumbar stability after graded facetectomy and laminectomy: a finite element study].

OBJECTIVE: To explore the effects on degenerative single segmental lumbar spinal stability after posterior graded laminectomy and facetectomy by a finite element method. METHODS: A finite element model of L3-S1 segments with a single segmental degeneration at L4-5 level was established. Different models of L4-L5 segmental instability after posterior graded laminectomy and facetectomy were established. And interior 1/3, 1/2, 2/3 of laminar and bilateral facet joints were resected. Physical loads were applied to the models and the changes of range of motion (ROM) at L4-5 level in different models were recorded during flexion, extension, lateral bending and rotation. RESULTS: As compared to preoperative model, after resecting 1/3 bilateral facet joints at L4-5 level, L4-5 segmental ROM increased 18% during flexion, 27% during extension and 45% during torsion. And the increased degree of ROM became more obvious along with a greater resection range of bilateral facet joints. No significant difference existed in L4-5 segmental ROM during lateral bending in all models. CONCLUSION: Facet joints play vital roles in lumbar segmental stability. And segmental instability may occur when 1/3 bilateral facet joints are resected.

Comparison of HER2 status by fluorescence in situ hybridisation and immunohistochemistry in gastric cancer.

AIM OF THE STUDY: To investigate the differences and relevance, and to evaluate the clinical significance of fluorescence in situ hybridisation and immunohistochemistry (IHC) in detecting HER2 in gastric cancer tissues. MATERIAL AND METHODS: The expression of HER2 protein and the amplification of the HER2 gene in 118 gastric cancer tissues were detected by immunohistochemistry and fluorescence in situ hybridisation, respectively. RESULTS: Using IHC, we found that in 40 cases (33.9%) the HER2 expression was at level 0, in 33 cases (28.0%) the HER2 expression was at level 1+, in 16 cases (14%) the HER2 expression was at level 2+, and in 29 cases (25.6%) the HER2 expression was at level 3+, respectively. Using the FISH test, 38 of 118 cases (32.2%) were judged as positive results. The concordance rate between the results of IHC and FISH in all cases was 85.6%. The concordance rate of IHC and FISH was high in cases of HER2 expression at level 0, 1+ and 3+ according to IHC, but low in cases of 2+ according to IHC (43.8%). CONCLUSIONS: Immunohistochemistry cannot predict HER2 gene amplification accurately. The FISH test should be executed in IHC 2+ cases.

Lactate score classification of hepatocellular carcinoma helps identify patients with tumors that respond to immune checkpoint blockade therapy.

PURPOSE: Hepatocellular carcinoma (HCC) responds poorly to immunotherapy, and the durable response rate is 10-20%. Here, we aim to characterize HCC classifications based on lactate genes to identify patients who may benefit from immunotherapy. METHODS: Lactate-related genes were applied for HCC classification in the current study, and lactate Cluster 1 (LC1) and lactate Cluster 2 (LC2) were defined. Differential genes from LC1 and LC2 helped define the following lactate phenotype clusters: lactate phenotype Cluster 1 (LPC1), lactate phenotype Cluster 2 (LPC2) and lactate phenotype Cluster 3 (LPC3). Based on the cluster annotation, the lactate score was defined and analyzed to evaluate the immunotherapy response. RESULTS: All the classified clusters were analyzed, and they showed different immune signatures. The survival rate of LPC3 was higher than that of LPC2 (LPC3 vs. LPC2, P = 0.027) and LPC1 (LPC3 vs. LPC1, P = 0.027). Then, the lactate score was annotated and confirmed to be effective in predicting responses to immune checkpoint blockade therapy. CONCLUSION: In the current study, we developed a classification system for HCC and defined the lactate score, which was validated to be partially effective in estimating responses among tumor patients.

Dimeric ent-kauranoids isolated from Isodon japonica var. Glaucocalyx and their anti-inflammatory activities.

The phytochemical investigation of the aerial parts of Isodon japonica var. glaucocalyx afforded four undescribed (glaucocalyxin O-R, 1-4) and six known ent-kauranoids (5-10). Their structures were established using NMR and MS measurements. Compounds 1 and 2 are dimeric ent-kaurane-type diterpenoids. Moreover, the plausible biogenetic pathways for compounds 1 and 2 were proposed as Michael addition between two monomers. Eight compounds were assayed for their anti-inflammatory activity by evaluating NO production in LPS-induced RAW 267.4 cells, and compounds 7, 8 and 9 exhibited relatively remarkable anti-inflammatory activities at 10 µM.

Topological Spin Textures in an Insulating van der Waals Ferromagnet.

Generation and control of topological spin textures constitutes one of the most exciting challenges of modern spintronics given their potential applications in information storage technologies. Of particular interest are magnetic insulators, which due to low damping, absence of Joule heating and reduced dissipation can provide energy-efficient spin-textures platform. Here, it is demonstrated that the interplay between sample thickness, external magnetic fields, and optical excitations can generate a prolific paramount of spin textures, and their coexistence in insulating CrBr3 van der Waals (vdW) ferromagnets. Using high-resolution magnetic force microscopy and large-scale micromagnetic simulation methods, the existence of a large region in T-B phase diagram is demonstrated where different stripe domains, skyrmion crystals, and magnetic domains exist and can be intrinsically selected or transformed to each-other via a phase-switch mechanism. Lorentz transmission electron microscopy unveils the mixed chirality of the magnetic textures that are of Bloch-type at given conditions but can be further manipulated into Néel-type or hybrid-type via thickness-engineering. The topological phase transformation between the different magnetic objects can be further inspected by standard photoluminescence optical probes resolved by circular polarization indicative of an existence of exciton-skyrmion coupling mechanism. The findings identify vdW magnetic insulators as a promising framework of materials for the manipulation and generation of highly ordered skyrmion lattices relevant for device integration at the atomic level.

Eighteen iridoids from the roots and rhizomes of Valeriana jatamansi and their protective effects against α-hemolysin.

Thirteen previously undescribed iridoids (1-13), together with five known iridoids (14-18) were isolated from the roots and rhizomes of Valeriana jatamansi Jones. Their structures with absolute configurations were elucidated by analysis of MS, NMR, optical rotation and their experimental and calculated electronic circular dichroism spectra. All of the isolated compounds were tested for their protective effects against α-hemolysin-induced cell death in A549 cells. Compounds 14, 16 and 17 showed moderate protective effects, and compounds 15 and 18 showed weak protective effects.

Rhodococcus canchipurensis sp. nov., an actinomycete isolated from a limestone deposit site.

A novel actinobacterial strain, MBRL 353(T), was isolated from a sample collected from a limestone quarry at Hundung, Manipur, India. Comparison of 16S rRNA gene sequences of strain MBRL 353(T) and other members of the genus Rhodococcus showed sequence similarities ranging from 95.5 to 98.2 %, with strain MBRL 353(T) showing closest sequence similarity to Rhodococcus triatomae IMMIB RIV-085(T) (98.2 %) and Rhodococcus equi DSM 20307(T) (97.2 %). DNA-DNA hybridization results, however, revealed that DNA-DNA relatedness values between strain MBRL 353(T) and R. triatomae DSM 44892(T) (43.4 %) and R. equi DSM 20307(T) (33.4 %) were well below the 70 % limit for species identification. Strain MBRL 353(T) contained meso-diaminopimelic acid as the diagnostic diamino acid and galactose and arabinose in the cell wall. Mycolic acids were present. The major fatty acids were C(16 : 0) (45.7 %), C(18 : 1)ω9c (18.2 %) and 10-methyl C(18 : 0) (11.3 %). The only menaquinone detected was MK-8(H(2)), while the major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and one unknown phospholipid. The G+C content of the genomic DNA was 69.2 mol%. The phenotypic and genotypic data showed that strain MBRL 353(T) merits recognition as a representative of a novel species of the genus Rhodococcus for which the name Rhodococcus canchipurensis sp. nov. is proposed; the type strain is MBRL 353(T) (= KCTC 19851(T) = JCM 17578(T)).

Alishewanella solinquinati sp. nov., isolated from soil contaminated with textile dyes.

A novel Gram-negative, motile, rod-shaped, facultative anaerobic bacterial strain, KMK6(T), was isolated from soil contaminated with textile dyes from an industrial estate located at Ichalkaranji, Maharashtra, India, and its taxonomical position was established by using a polyphasic approach. The major cellular fatty acids included C17:1ω8c, summed feature 3 (C16:1ω7c and/or iso-C15:0 2-OH), C17:0, C16:0, and C18:1ω7c. The DNA G+C content of strain KMK6(T) was 48.8 mol %. 16S rRNA gene sequence analysis confirmed its placement in the genus Alishewanella, and exhibited sequence similarity levels of below 97 % to the type strains of validly published Alishewanella species. On the basis of genotypic and phenotypic evidence, strains KMK6(T) is considered to be a novel species of the genus Alishewanella, for which we propose that strain KMK6(T) (=NCIM 5295(T) =BCRC 17848(T)) is assigned to a novel species, Alishewanella solinquinati sp. nov.

Removal of chromium (VI) from electroplating wastewater using an anion exchanger derived from rice straw.

An anion exchanger from rice straw was used to remove Cr (VI) from synthetic wastewater and electroplating effluent. The exchanger was characterized using Fourier transform infrared (FTIR) spectrum and scanning electron microscopy (SEM), and it was found that the quaternary amino group and hydroxyl group are the main functional groups on the fibrous surface of the exchanger. The effect of contact time, initial concentration and pH on the removal of Cr (VI), and adsorption isotherms at different temperature, was investigated. The results showed that the removal of Cr (VI) was very rapid and was significantly affected by the initial pH of the solution. Although acidic conditions (pH = 2-6) facilitated Cr (VI) adsorption, the exchanger was effective in neutral solution and even under weak base conditions. The equilibrium data fitted well with Langmuir adsorption model, and the maximum Cr (VI) adsorption capacities at pH 6.4 were 0.35, 0.36 and 0.38 mmol/g for 15, 25 and 35 degrees C, respectively. The exchanger was finally tested with real electroplating wastewater, and at sorbent dosage of 10 g/L, the removal efficiencies for Cr (VI) and total Cr were 99.4% and 97.8%, respectively. In addition, the positive relationship between adsorbed Cr (VI) and desorbed Cl- suggested that Cr (VI) was mainly removed by ion exchange with chlorine.

Analysis of air bearing torsion pendulum moment of inertia measurements including nonlinear oscillation and damping.

For precise measurement of the moment of inertia (MOI) of asymmetric objects, using an air bearing torsional pendulum, the nonlinearity of the torsion bar and the damping effect caused by the interaction between air and sample need to be included in the analysis. The instantaneous undamped natural frequency and instantaneous damping coefficient of the motion are obtained from the Hilbert transform of the angular displacement signal and are used for data fitting to calculate the MOI. Measurements for algorithm verification were made using a special sample with large windvanes to increase the damping effect. The nonlinear analysis of the MOI experimental results indicated a relative error of less than 0.1% compared with 0.3% for classical linear analysis of the data.

Five undescribed guanidine alkaloids from Plumbago zeylanica.

Five undescribed guanidine alkaloids, plumbagines HK (1-4) and plumbagoside E (5), as well as five known analogues (6-10) were isolated from the roots of Plumbago zeylanica. Their structures were established by extensive spectroscopic analyses and chemical methods. In addition, 1-10 were accessed their anti-inflammatory activities by measuring nitric oxide (NO) concentrations in LPS-induced RAW 264.7 cells. However, all compounds especially 1 and 3-5 could not inhibit the secretion of NO but significant increase the secretion of NO. The result reminded us that 1-10 may become potential novel immune potentiators.

Five undescribed abietane-type diterpenes of Callicarpa macrophylla.

A phytochemical investigation of the medicinal plant Callicarpa macrophylla resulted in the characterization of two rare rearrangement abietane-type diterpenoids, macrophypene F-G (1-2), and three abietane diterpenoids, named macrophypene H-J (3-5). Additionally, five known diterpenoids (6-10) were identified. The structures of the newly discovered compounds were fully established through extensive analysis of HRESIMS, 1D and 2D NMR data. The absolute configurations of the isolated compounds were determined using CD comparison, chemical methods, and X-ray crystal diffraction experiments. Subsequently, all isolated diterpenoids were evaluated for their inhibitory effects on extracellular PCSK9 protein levels by PCSK9 AlphaLISA screening. Jiadfenoic acid B (6, 56.80% inhibition at 20 µM) and holophyllin F (10, 43.18% inhibition at 20 µM) significantly decreased PCSK9 protein levels in medium of HepG2 cells.

International Society of University Colon and Rectal Surgeons survey of surgeons' preference on rectal cancer treatment.

PURPOSE: Rectal cancer treatment has a wide range of possible approaches from radical extirpative surgery to nonoperative watchful waiting following chemoradiotherapy, with or without, additional chemotherapy. Our goal was to assess the personal opinion of active practicing surgeons on rectal cancer treatment if he/she was the patient. METHODS: A panel of the International Society of University Colon and Rectal Surgeons (ISUCRS) selected 10 questions that were included in a questionnaire that included other items including demographics. The questionnaire was distributed electronically to ISUCRS fellows and other surgeons included in our database and remained open from April 16 to 28, 2020. RESULTS: One hundred sixty-three specialists completed the survey. The majority of surgeons (n=65, 39.9%) chose the minimally invasive (laparoscopic) surgery for their personal treatment of rectal cancer. For low-lying rectal cancer T1 and T2, the treatment choice was standard chemoradiation+local excision (n=60, 36.8%) followed by local excision±chemoradiotherapy if needed (n=55, 33.7%). In regards to locally advanced low rectal cancer T3 or greater, the preference of the responders was for laparoscopic surgery (n=65, 39.9%). We found a statistically significant relationship between surgeons' age and their preference for minimally invasive techniques demonstrating an age-based bias on senior surgeons' inclination toward open approach. CONCLUSION: Our survey reveals an age-based preference by surgeons for minimally invasive surgical techniques as well as organ-preserving techniques for personal treatment of treating rectal cancer. Only 1/4 of specialists do adhere to the international guidelines for treating early rectal cancer.