Objective: To investigate the efficacy of magnesium-strontium co-doped hydroxyapatite mineralized collagen (MSHA/Col) in improving the bone repair microenvironment and enhancing bone regeneration capacity, providing a strategy to address the insufficient biomimetic composition and limited bioactivity of traditional hydroxyapatite mineralized collagen (HA/Col) scaffolds. Methods: A high-molecular-weight polyacrylic acid-stabilized amorphous calcium magnesium strontium phosphate precursor (HPAA/ACMSP) was prepared. Its morphology and elemental distribution were characterized by high-resolution transmission electron microscopy (TEM) and energy-dispersive spectroscopy. Recombinant collagen sponge blocks were immersed in the HPAA/ACMSP mineralization solution. Magnesium-strontium co-doped hydroxyapatite was induced to deposit within collagen fibers (experimental group: MSHA/Col; control group: HA/Col). The morphological characteristics of MSHA/Col were observed using scanning electron microscopy (SEM). Its crystal structure and chemical composition were analyzed by X-ray diffraction and Fourier transform infrared spectroscopy, respectively. The mineral phase content was evaluated by thermogravimetric analysis. The scaffold's porosity, ion release, and in vitro degradation performance were also determined. For cytological experiments, CCK-8 assay, live/dead cell staining, alkaline phosphatase staining, alizarin red S staining, RT-qPCR, and western blotting were used to evaluate the effects of the MSHA/Col scaffold on the proliferation, viability, early osteogenic differentiation activity, late mineralization capacity, and gene and protein expression levels of key osteogenic markers [runt-related transcription factor 2 (Runx2), collagen type Ⅰ (Col-Ⅰ), osteopontin (Opn), and osteocalcin (Ocn)] in mouse embryonic osteoblast precursor cells (MC3T3-E1). Results: HPAA/ACMSP appeared as amorphous spherical nanoparticles under TEM, with energy spectrum analysis showing uniform distribution of carbon, oxygen, calcium, phosphorus, magnesium, and strontium elements. SEM results of MSHA/Col indicated successful complete intrafibrillar mineralization. Elemental analysis showed the mass fractions of magnesium and strontium were 0.72% (matching the magnesium content in natural bone) and 2.89%, respectively. X-ray diffraction revealed characteristic peaks of hydroxyapatite crystals (25.86°, 31°-34°). Infrared spectroscopy results showed characteristic absorption peaks for both collagen and hydroxyapatite. Thermogravimetric analysis indicated a mineral phase content of 78.29% in the material. The scaffold porosity was 91.6% ± 1.1%, close to the level of natural bone tissue. Ion release curves demonstrated sustained release behavior for both magnesium and strontium ions. The in vitro degradation rate matched the ingrowth rate of new bone tissue. Cytological experiments showed that MSHA/Col significantly promoted MC3T3-E1 cell proliferation (130% increase in activity at 72 h, P < 0.001). MSHA/Col exhibited excellent efficacy in promoting osteogenic differentiation, significantly upregulating the expression of osteogenesis-related genes and proteins (Runx2, Col-Ⅰ, Opn, Ocn) (P < 0.01). Conclusion The MSHA/Col scaffold achieves dual biomimicry of natural bone in both composition and structure, and effectively promotes osteogenic differentiation at the genetic and protein levels, breaking through the functional limitations of pure hydroxyapatite mineralized collagen. This provides a new strategy for the development of functional bone repair materials

The c-Jun N-terminal kinase （JNK） signaling pathway， a key member of the mitogen-activated protein kinase （MAPK） family， plays a central role in the pathogenesis and progression of central nervous system （CNS） diseases by regulating core biological processes such as apoptosis， inflammatory responses， synaptic plasticity， and autophagy. This article sorts out and analyzes relevant literature published domestically and internationally in recent years， summarizing the mechanisms of action of the JNK signaling pathway in common CNS diseases and the research progress in traditional Chinese medicine （TCM） interventions in CNS diseases through the regulation of the JNK signaling pathway. Studies have shown that active components of TCM， such as berberine， paeoniflorin， and astragaloside Ⅳ， as well as compound formulations like Heixiaoyao san， Ditan tang， and Buyang huanwu tang， can exert neuroprotective effects in various CNS disorders， including Alzheimer’s disease， Parkinson’s disease， cerebral ischemia-reperfusion injury， and epilepsy， by inhibiting the aberrant activation of the JNK signaling pathway， thereby alleviating neuroinflammation， oxidative stress， and neuronal apoptosis， while improving synaptic function and cognitive behavioral deficits， regulating autophagy， and maintaining blood-brain barrier integrity.

ObjectiveTo investigate the mechanism through which miR‑21 improves chronic renal fibrosis in mice via targeted modulation of the phosphatase and tensin homolog （PTEN）/protein kinase B （AKT）/mammalian target of rapamycin （mTOR） pathway. MethodsThirty‑two chronic kidney disease model mice were randomly divided into four groups （n=8 each group）： model group， miR‑21 overexpression group， miR‑21 inhibition group， and miR‑21 inhibition + MK‑2206 group. Eight healthy mice were included as the control group. The miR‑21 overexpression， miR‑21 inhibition， and miR‑21 inhibition + MK‑2206 groups received tail‑vein injections of lentivirus （50 μL， 1×10⁸ TU per mouse） once weekly for three weeks. The control and model groups were injected with an equal volume of empty vector （LV‑NC）. The miR‑21 inhibition + MK‑2206 group additionally received gavage of the AKT/mTOR pathway inhibitor MK‑2206 （480 mg/kg） once weekly for three weeks. The expressions of miR‑21， 24 h urinary protein， serum creatinine （Scr）， blood urea nitrogen （BUN）， and renal tissue levels of collagen Ⅰ， collagen Ⅲ， α‑smooth muscle actin （α‑SMA）， and PTEN protein， as well as p‑AKT/AKT and p‑mTOR/mTOR ratios， were compared among groups. HE staining was used to observe pathological changes in renal tissue， and Masson staining was used to observe the degree of renal fibrosis. A dual‑luciferase assay was performed to verify the targeting relationship between miR‑21 and PTEN. ResultsCompared with the model group， miR‑21 expression in renal tissue increased in the miR‑21 overexpression group （P<0.05） and decreased in the miR‑21 inhibition group （P<0.05）. Compared with the model group， the miR‑21 overexpression group showed increased 24 h urinary protein， Scr， BUN， and renal tissue expression of collagen Ⅰ， collagen Ⅲ， and α‑SMA （all P<0.05）， while these indicators decreased in the miR‑21 inhibition group （P<0.05）. Compared with the miR‑21 inhibition group， the miR‑21 inhibition + MK‑2206 group exhibited lower 24‑h urinary protein， Scr， BUN， and renal tissue expression of Collagen Ⅰ， Collagen Ⅲ， and α‑SMA （all P<0.05）. Compared with the model group， the miR‑21 overexpression group showed decreased PTEN protein expression （P<0.05） and increased p‑AKT/AKT and p‑mTOR/mTOR ratios （P<0.05）， while the miR‑21 inhibition group showed increased PTEN expression （P<0.05） and decreased p‑AKT/AKT and p‑mTOR/mTOR ratios （P<0.05）. Compared with the miR‑21 inhibition group， the miR‑21 inhibition + MK‑2206 group had lower p‑AKT/AKT and p‑mTOR/mTOR ratios （P<0.05）， with no significant difference in PTEN protein expression. HE and Masson staining showed normal kidney structure and almost no fibrosis in the control group. The model group exhibited glomerular enlargement， capillary loop adhesion， and focal fibrosis. The miR-21 overexpression group showed severe destruction of glomerular structure， accompanied by extensive fibrosis and renal tubular atrophy. The pathological changes and degree of fibrosis were alleviated in the miR-21 inhibition group. The miR-21 inhibition + MK-2206 group showed only mild pathological changes and mild fibrosis， with the interstitium being largely normal. Compared with PTEN-WT + NC mimics 1， the relative luciferase activity in the PTEN-WT + miR-21 mimics group decreased （P<0.001）. There was no statistically significant difference in relative luciferase activity between PTEN-WT + NC mimics group and PTEN-MUT + miR-21 mimics group. ConclusionmiR‑21 may improve renal function indicators and alleviate renal fibrosis in chronic kidney disease mice via targeted modulation of PTEN and subsequently inhibiting the AKT/mTOR pathway.

Steroid-induced avascular necrosis of femoral head（SANFH） is a bone and joint disease caused by prolonged and excessive steroid use. Its typical pathological features involve progressive circulatory disorders in the blood supply system of femoral head， leading to osteocyte apoptosis and bone tissue necrosis. As the disease progresses， it ultimately results in structural collapse and necrotic lesions of the femoral head， severely affecting patients' limb function and quality of life. Glucocorticoids mediate pathological damage through dual mechanisms， on the one hand， they disrupt the dynamic equilibrium between bone formation and resorption by suppressing osteoblast differentiation activity and activating osteoclastogenesis， on the other hand， they induce lipid metabolism disorders， inhibit angiogenesis， and impair endothelial cell function， thereby triggering microcirculatory disorders. Epimedii Folium and its active components exhibit multidimensional regulatory effects in SANFH prevention and treatment. Literature review reveals that it is rich in multiple active ingredients， primarily including total flavonoids of Epimedii Folium， icaritin， icariin， kaempferol， icariside Ⅱ， etc. These compounds exert multiple pharmacological effects（regulating bone metabolic homeostasis， modulating angiogenesis， correcting lipid metabolism disorders， and controlling cellular autophagy processes） through multiple signaling pathways， including Wnt/β-catenin， transforming growth factor（TGF）-β/bone morphogenetic protein（BMP）/Smad， mitogen-activated protein kinase（MAPK）， phosphoinositide 3-kinase/protein kinase B（PI3K/Akt）， osteoprotegerin/receptor activator of nuclear transcription factor-κB ligand/receptor activator of nuclear transcription factor-κB（OPG/RANKL/RANK）， etc. Based on existing research findings， this paper systematically elucidates the intervention mechanisms of active components in Epimedii Folium on key pathological processes of SANFH through the above pathways. It also deeply analyzes their regulatory roles in key nodes of different signaling pathways， aiming to provide valuable references for future clinical treatment and experimental research.

AIM: To explore the effect of dihydroquercetin on visual function in mice with form deprivation myopia based on the NOD-like receptor thermoprotein domain-related protein 3(NLRP3)inflammasome pathway.METHODS: The C57BL/6 mice were randomly divided into control group and form deprivation myopia model group, and the form deprivation myopia model group was constructed by covering the right eye with a translucent eye patch. After successful modeling, the mice in the model group of form deprivation myopia were randomly divided into model group, low-, medium- and high-dose dihydroquercetin groups, and high-dose dihydroquercetin + NLRP3 agonist group. The diopter and axial length of mice in each group were detected. The kit was used to detect the levels of superoxide dismutase(SOD)and malondialdehyde(MDA)in retinal tissue. RT-qPCR was used to detect the mRNA expressions of NLRP3, apoptosis-associated spot-like protein(ASC), Caspase-1, IL-1β and IL-18 in retinal tissues. Western blot was used to detect the expression of NLRP3, ASC, cleaved Caspase-1, IL-1β and IL-18 proteins in retinal tissues. TUNEL staining was used to detect apoptosis in retinal tissue.RESULTS: Compared with the control group, the diopter of the mice in the model group decreased, and axial length increased, and the SOD decreased whereas MDA, NLRP3, ASC, Caspase-1, IL-1β, IL-18 increased, and the rate of apoptosis in retinal tissue increased(all P<0.05). Compared with the model group, the diopter of mice in the low-, medium- and high-dose dihydroquercetin groups increased, axial length shortened, the SOD increased, whereas MDA, NLRP3, ASC, Caspase-1, IL-1β, IL-18 decreased, and the rate of apoptosis in retinal tissue decreased(all P<0.05). Compared with the high-dose dihydroquercetin group, the high-dose dihydroquercetin+NLRP3 agonist group had reduced diopter, increased axial length, decreased SOD levels, elevated MDA, NLRP3, ASC, Caspase-1, IL-1β, and IL-18 levels, as well as increased apoptosis rate in retinal tissue(all P<0.05).CONCLUSION: Dihydroquercetin can improve visual function in mice with form deprivation myopia by inhibiting pyroptosis and oxidative stress responses, which may be related to the suppression of NLRP3 inflammasome. NLRP3 agonists can partially mitigate the effects of high-dose dihydroquercetin on form deprivation myopia in mice.

ObjectiveTo investigate the effects of exogenous nitric oxide （NO） on the accumulation and quality formation mechanism of flavonoids in Scutellariae Radix. MethodsFresh roots of Scutellaria baicalensis were treated with sodium nitroprusside （SNP） solutions at concentrations of 0.0， 7.5， and 20 mmol·L^-1， respectively. Kits and supporting reaction systems were used to determine the following indicators of samples in each group， including （1） reactive oxygen species： changes in the content of nitric oxide （NO）， superoxide anion （O2-·）， and hydrogen peroxide （H₂O₂）， （2） lipid oxidation products： changes in the content of malondialdehyde （MDA）， （3） antioxidant enzymes： changes in the activity of superoxide dismutase （SOD）， catalase （CAT）， and peroxidase （POD）， and （4） metabolic key enzymes and metabolic intermediates： Changes in the activity of phenylalanine ammonia-lyase （PAL） and the content of 1，3-diphosphoglycerate （1，3-DPG）. High-performance liquid chromatography （HPLC） was used to determine the changes in the content of secondary metabolites in flavonoids such as baicalin， wogonoside， baicalein， and wogonin in each group. ResultsCompared with that on day 0， during the treatment with 20 mmol·L^-1 SNP solution， the content of NO， O2-·， H₂O₂， and MDA in fresh roots of Scutellaria baicalensis increased significantly （P<0.01）， by 138.7%， 75.7%， 292.9%， and 140.3% respectively. The activity of SOD， CAT， and POD increased by 100.7%， 41.4%， and 70.4% respectively （P<0.01）， and that of PAL increased by 111.1% （P<0.01）. The content of the secondary metabolites baicalin and wogonoside remained basically unchanged， while that of baicalein and wogonin increased by 401.3% and 457.9% respectively （P<0.01）. The content of 1，3-DPG increased by 165.0% （P<0.01）. In the 7.5 mmol·L^-1 SNP solution treatment group， the stress degree was relatively mild. Compared with that on day 0， the content of NO， O2-·， H₂O₂， and MDA increased by 76.2%， 57.7%， 221.4%， and 99.7% respectively （P<0.01）. The activity of antioxidant enzymes SOD， CAT， and POD increased by 79.5%， 55.6%， and 51.9% respectively （P<0.01）， and that of PAL increased by 69.0% （P<0.01）. The content of baicalein and wogonin increased by 204.7% and 272.2% respectively （P<0.01）， and that of 1，3-DPG increased by 128.0% （P<0.01）. The 20 mmol·L^-1 SNP group showed better performance than the 7.5 mmol·L^-1 SNP group. ConclusionSNP can simulate the physiological state of Scutellaria baicalensis under stress conditions， activate the antioxidant protection mechanism， promote the biosynthesis of flavonoids in Scutellariae Radix， and significantly improve the quality of medicinal materials in Scutellariae Radix.

Objective: Blood safety surveillance is a critical measure for the objective assessment of blood quality and enhancing transfusion safety. This study aims to comprehensively understand the current status of blood safety surveillance and management in blood collection and supply institutions in Sichuan Province, systematically analyze existing problems and vulnerabilities, and provide a basis for optimizing management strategies and improving capabilities to ensure blood safety. Methods: The Blood Safety Surveillance questionnaire was designed, covering adverse donor reaction reporting, management of adverse events, and transfusion adverse reaction feedback. An online survey was conducted via Questionnaire Star platform among 21 blood collection and supply institutions in the province, gathering information on management systems, process implementation, and utilization of monitoring data. The collected data were organized and statistically analyzed using Excel. Results: The questionnaire response rate and validity rate were both 100%. Blood collection and supply institutions in Sichuan Province have generally established a blood safety surveillance system and achieved positive outcomes. Regarding adverse events in blood collection and supply, 95.24% (20 institutions) have established reporting procedures, and 66.67% (14) collect information through multiple channels such as internal reports, external reports, and statistical trend feedback. A total of 90.48% (19) institutions regularly summarize and analyze adverse event data, and 85.71% (18) produce reports with improvement recommendations based on this analysis.71.43% (15) institutions implement reward and penalty measures, and 71.43% (15) report underreporting or omission due to accountability or performance concerns. In terms of monitoring adverse blood donation reactions, all blood collection and supply institutions have established full-process management systems.76.19% (16) collect data through multiple approaches, including on-site donation records, voluntary donor reports, and donor follow-ups. Adverse reactions were followed up in 95.24% (20) of institutions with 65% (13) completing follow-ups within 24 hours.80.95% (17) have established investigation procedures, while 66.67% (14) believe underreporting or omission still occurs. All blood collection and supply institutions regularly compile statistics on adverse donation reactions. Of these, 85.71% (18) institutions providing feedback to management departments and 90.48% (19) analyzing the data and making recommendations.76.19% (16) institutions use monitoring data for return donor management and targeted care, and 71.43% (15 stations) incorporate it into management reviews. Regarding adverse transfusion reactions, 95.24% (20) institutions have established and implemented procedures for isolating, recalling, and tracing of problematic blood units. However, only 42.86% (9) have established feedback mechanisms of adverse transfusion reaction with hospitals, and only 19.05% (4) support direct reporting via information systems.47.62% (10) institutions regularly analyze adverse transfusion reaction data, and 19.05% (4) provide feedback and recommendations to relevant hospitals. All blood collection and supply institutions reported challenges in collecting hospital feedback, citing complexities in data collection and reporting processes. Conclusion: Blood safety surveillance systems have been preliminarily established in Sichuan Province. However, further strengthening is still required, including conducting in-depth data analysis and utilization, standardizing the configuration of emergency medications and equipment, and improving feedback mechanisms for adverse transfusion reactions. To improve the overall level of blood safety management, it is recommended to strengthen closed-loop data management, improve feedback mechanisms between blood collection and supply institutions and hospitals, foster a non-punitive reporting culture, and systematically advance the regionalization and standardization of the monitoring system. These efforts will contribute to sustainably improving the overall effectiveness and sustainability of blood safety management.

ObjectiveHeadspace solid-phase microextraction-gas chromatography-mass spectrometry（HS-SPME-GC-MS） and GC-triple quadrupole MS（GC-QqQ-MS） in combination with non-targeted and targeted metabolomics were employed to systematically analyze the chemical composition differences of Xihuangwan prepared with natural musk and artificial musk， and establish an identification system for them. MethodsThe volatile components of 9 batches of Xihuangwan samples from 8 manufacturers were analyzed by HS-SPME-GC-MS non-targeted metabolomics， and identified by comparing their MS data with the National Institute of Standards and Technology（NIST） spectral library. Orthogonal partial least squares-discriminant analysis（OPLS-DA） was used to identify differential volatile components of Xihuangwan prepared with natural musk and artificial musk. Additionally， GC-QqQ-MS targeted metabolomics was applied to quantify the levels of α-pinene， β-elemene， muscone， dehydroepiandrosterone， bornyl acetate， and octyl acetate in 27 batches of samples from 9 manufacturers. Cluster analysis， principal component analysis（PCA）， and partial least squares-discriminant analysis（PLS-DA） were conducted to further explore the differences in volatile components between Xihuangwan samples prepared with natural musk and artificial musk. ResultsNon-targeted metabolomics identified 291 volatile compounds in Xihuangwan， including alkanes， esters， alkanes， alcohols， ketones， naphthalenes and others. OPLS-DA analysis revealed distinct separation between Xihuangwan samples containing artificial musk（A1， C1， D1， E1， F1， G1， I1） and those containing natural musk（H1， H3）. A total of 30 differential metabolites were identified. The relative contents of these 30 differential metabolites were visualized using a radar chart， revealing significant differences in the levels of octanol， borneol acetate and muscone. Cluster analysis and PCA results from targeted metabolomics indicated that Xihuangwan could be classified into two distinct groups：one composed of natural musk（H1， H3） and the other of artificial musk， sample H2. PLS-DA identified muscone， octyl acetate， and dehydroepiandrosterone as key differential volatile components. Although no significant difference was observed in the content of octyl acetate between the two groups， statistically significant differences were found for muscone and dehydroepiandrosterone（P<0.05）. ConclusionMuscone and dehydroepiandrosterone can be used for the differentiation of Xihuangwan samples containing natural musk from those containing artificial musk. This study systematically and comprehensively analyzed the differences in the types and contents of major volatile components in Xihuangwan prepared with natural musk and artificial musk， providing a scientific basis for quality evaluation and control of Xihuangwan.

ObjectiveHeadspace solid-phase microextraction-gas chromatography-mass spectrometry（HS-SPME-GC-MS） and GC-triple quadrupole MS（GC-QqQ-MS） in combination with non-targeted and targeted metabolomics were employed to systematically analyze the chemical composition differences of Xihuangwan prepared with natural musk and artificial musk， and establish an identification system for them. MethodsThe volatile components of 9 batches of Xihuangwan samples from 8 manufacturers were analyzed by HS-SPME-GC-MS non-targeted metabolomics， and identified by comparing their MS data with the National Institute of Standards and Technology（NIST） spectral library. Orthogonal partial least squares-discriminant analysis（OPLS-DA） was used to identify differential volatile components of Xihuangwan prepared with natural musk and artificial musk. Additionally， GC-QqQ-MS targeted metabolomics was applied to quantify the levels of α-pinene， β-elemene， muscone， dehydroepiandrosterone， bornyl acetate， and octyl acetate in 27 batches of samples from 9 manufacturers. Cluster analysis， principal component analysis（PCA）， and partial least squares-discriminant analysis（PLS-DA） were conducted to further explore the differences in volatile components between Xihuangwan samples prepared with natural musk and artificial musk. ResultsNon-targeted metabolomics identified 291 volatile compounds in Xihuangwan， including alkanes， esters， alkanes， alcohols， ketones， naphthalenes and others. OPLS-DA analysis revealed distinct separation between Xihuangwan samples containing artificial musk（A1， C1， D1， E1， F1， G1， I1） and those containing natural musk（H1， H3）. A total of 30 differential metabolites were identified. The relative contents of these 30 differential metabolites were visualized using a radar chart， revealing significant differences in the levels of octanol， borneol acetate and muscone. Cluster analysis and PCA results from targeted metabolomics indicated that Xihuangwan could be classified into two distinct groups：one composed of natural musk（H1， H3） and the other of artificial musk， sample H2. PLS-DA identified muscone， octyl acetate， and dehydroepiandrosterone as key differential volatile components. Although no significant difference was observed in the content of octyl acetate between the two groups， statistically significant differences were found for muscone and dehydroepiandrosterone（P<0.05）. ConclusionMuscone and dehydroepiandrosterone can be used for the differentiation of Xihuangwan samples containing natural musk from those containing artificial musk. This study systematically and comprehensively analyzed the differences in the types and contents of major volatile components in Xihuangwan prepared with natural musk and artificial musk， providing a scientific basis for quality evaluation and control of Xihuangwan.

Ulcerative colitis is a chronic relapsing inflammatory bowel disease. Modern research indicates that immune dysregulation resulting from disruptions in circadian rhythm is closely associated with its pathogenesis. Both Western chronomedicine and traditional Chinese medicine（TCM）" treatment based on temporal factors" emphasize the temporal relationship between natural rhythms and human physiology and pathology. The " midnight-noon and ebb-flow " theory represents the concrete application and deepening of TCM " treatment based on temporal factors" within the realm of chronomedicine. This article correlates the onset time of ulcerative colitis with specific periods in the " midnight-noon and ebb-flow"theory：the Mao period（05：00-07：00），when the yangming large intestine meridian of hand is dominant； the Si period（09：00-11：00），when the taiyin spleen meridian of foot is dominant； and the You period（17：00-19：00），when the shaoyin kidney meridian of foot is dominant. According to this perspective，if the disease manifests during the Mao period，the pathogenesis is attributed to dampnessheat accumulation and disorder of qi and blood. Treatment should focus on clearing heat，resolving dampness，and harmonizing qi and blood，using modified formulas such as Shaoyao Decoction or Baitouweng Decoction. If it occurs during the Si period，the pathogenesis involves spleen deficiency with dampness obstruction and disharmony of qi and blood. Treatment should focus on strengthening the spleen，eliminating dampness，and restoring qi and blood，using modified formulas such as Huangya Decoction or Shenling Baizhu Powder. If it presents during the You period，the pathogenesis is characterized by fire failing to warm earth，and consumption resulting in qi and blood leakage. Treatment should focus on warming the kidney and spleen，and securing qi and blood，using modified formulas such as Sishen Pill or Tianhun Decoction. In addition to oral administration of Chinese herbal medicine，comprehensive therapies including acupuncture，herbal enemas，and acupoint application can provide novel insights for the clinical diagnosis and treatment of ulcerative colitis.