Purpose: Models for predicting postoperative overall survival of patients with metaplastic breast cancer have not yet been discovered. The purpose of this study is to establish a model for predicting postoperative overall survival of metaplastic breast cancer patients. Methods: Patients in the Surveillance, Epidemiology, and End Results database diagnosed with MBC from 2010 to 2015 were selected and randomized into a SEER training cohort and an internal validation cohort. We identified independent prognostic factors after MBC surgery based on multivariate Cox regression analysis to construct nomograms. The discriminative and predictive power of the nomogram was assessed using Harrell's consistency index (C-index) and calibration plots. The decision curve analysis (DCA) was used to evaluate the clinical usefulness of the model. We verify the performance of the prediction model with a Chinese multi-center data set. Results: Multifactorial analysis showed that age at diagnosis, T stage, N stage, M stage, tumor size, radiotherapy, and chemotherapy were important prognostic factors affecting OS. The C-index of nomogram was higher than the eighth edition of the AJCC TNM grading system in the SEER training set and validation set. The calibration chart showed that the survival rate predicted by the nomogram is close to the actual survival rate. It has also been verified in the SEER internal verification set and the Chinese multi-center data set. Conclusion: The prognostic model can accurately predict the post-surgical OS rate of patients with MBC and can provide a reference for doctors and patients to establish treatment plans.
S-Adenosylhomocysteine hydrolase (AdoHcy hydrolase) crystallizes from solutions containing the intermediate analogue neplanocin A with the analogue bound in its 3'-keto form at the active sites of all of its four subunits and the four tightly bound cofactors in their reduced (NADH) state. The enzyme is in the closed conformation, which corresponds to the structure in which the catalytic chemistry occurs. Examination of the structure in the light of available, very detailed kinetic studies [Porter, D. J., Boyd, F. L. (1991) J. Biol. Chem. 266, 21616−21625. Porter, D. J., Boyd, F. L. (1992) J. Biol. Chem. 267, 3205−3213. Porter, D. J. (1998) J. Biol. Chem. 268, 66−73] suggests elements of the catalytic strategy of AdoHcy hydrolase for acceleration of the reversible conversion of AdoHcy to adenosine (Ado) and homocysteine (Hcy). The enzyme, each subunit of which possesses a substrate-binding domain that in the absence of substrate is in rapid motion relative to the tetrameric core of the enzyme, first binds substrate and ceases motion. Probably concurrently with oxidation of the substrate to its 3'-keto form, the closed active site is "sealed off" from the environment, as indicated by a large (108-9-fold) reduction in the rate of departure of ligands, a feature that prevents exposure of the labile 3'-keto intermediates to the aqueous environment. Elimination of the 5'-substituent (Hcy in the hydrolytic direction, water in the synthetic direction) generates the central intermediate 4',5'-didehydro-5'-deoxy-3'-ketoadenosine. Abortive 3'-reduction of the central intermediate is prevented by a temporary suspension of all or part of the redox catalytic power of the enzyme during the existence of the central intermediate. The abortive reduction is 104-fold slower than the productive reductions at the ends of the catalytic cycle and has a rate constant similar to those of nonenzymic intramolecular model reactions. The mechanism for suspending the redox catalytic power appears to be a conformationally induced increase in the distance across which hydride transfer must occur between cofactor and substrate, the responsible conformational change again being that which "seals" the active site. The crystal structure reveals a well-defined chain of three water molecules leading from the active site to the subunit surface, which may serve as a relay for proton exchange between solvent and active site in the closed form of the enzyme, permitting maintenance of active-site functional groups in catalytically suitable protonation states.
Sulfonylureas and glinides are commonly used oral insulin secretagogues (ISs) that act on the pancreatic ATP-sensitive potassium (KATP) channel to promote insulin secretion in order to lower the blood glucose level. Physiologically, KATP channels are inhibited by intracellular ATP and activated by Mg-ADP. Therefore, they sense the cellular energy status to regulate the permeability of potassium ions across the plasma membrane. The pancreatic KATP channel is composed of the pore-forming Kir6.2 subunits and the regulatory SUR1 subunits. Previous electrophysiological studies have established that ISs bind to the SUR1 subunit and inhibit the channel activity primarily by two mechanisms. First, ISs prevent Mg-ADP activation. Second, ISs inhibit the channel activity of Kir6.2 directly. Several cryo-EM structures of the pancreatic KATP channel determined recently have provided remarkable structural insights into these two mechanisms.
The root of Rehmannia glutinosa (R. glutinosa) is commonly used in various traditional Chinese herbal formulae to ameliorate nephropathy; however, little is known about its active component(s) and mechanisms. In the present study, we examined the protective effect and potential mechanism of rehmapicrogenin, a monomeric compound extracted from R. glutinosa, against Adriamycin (ADR)-induced nephropathy (AN) in vivo and in vitro. In this study, an ADR-induced kidney injury model was employed to investigate the nephroprotective effects of rehmapicrogenin in mice. In vivo, ELISA kits, flow cytometry, haematoxylin-eosin staining, immunofluorescence techniques, and western blotting were used to evaluate the effect of rehmapicrogenin on kidney injury in mice. In vitro, the effects of rehmapicrogenin on NRK-52E cellular damage induced by ADR were determined using the 3-(4,5-dimethylthiazolyl-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The mechanism was investigated using ELISA kits, flow cytometry and In-Cell Western™ blotting. In vivo, rehmapicrogenin treatment significantly attenuated the pathological changes in the kidney induced by ADR; rescued weight, serum creatinine (Scr), blood urea nitrogen (BUN) and urine albumin (U-ALB) levels; reduced reactive oxygen species (ROS) accumulation; and decreased oxidative stress, the apoptosis rate, and cell survival in ADR-treated mice. Importantly, both in vivo and in vitro experimental results demonstrated that rehmapicrogenin regulates the Nrf2/ARE signalling pathway, the most important pathway for oxidative stress. Rehmapicrogenin attenuated ADR-induced kidney damage by reducing oxidative stress through the oestrogen receptor pathway. Moreover, after treatment with ICI 182780 (the oestrogen receptor-nonspecific antagonist Faslodex), the improvement induced by rehmapicrogenin was significantly reversed. In conclusion, rehmapicrogenin attenuates kidney damage by reducing inflammatory factor release through the oestrogen signalling pathway.
Diet-induced obese (DIO) mice have been commonly used as an animal model in the efficacy assessment for new drug candidates. Although high-fat feeding has been reported to cause profound physiological changes, including the expression of drug-metabolizing enzymes, limited studies have been reported regarding the effect of obesity/diabetes on pharmacokinetics (PK) in animals. In this study, we investigated PK profiles of three 11 -HSD-1 inhibitors in the DIO mice and compared them to the normal lean mice. After oral administration, the in vivo exposure (AUC) of all three compounds was higher in DIO mice, which was consistent with the observed lower systemic clearance (CL) in DIO mice compared to lean mice. As illustrated by Compound E, a compound metabolized predominantly by CYP3A and 2C, the metabolic profiles for Compound E were qualitatively similar between DIO and lean mice, but quantitatively lower in the DIO mice. Indeed, P-450 activities for CYP3A and 2C as well as 2D were found to be lower in liver microsomes prepared from DIO mice. The calculated hepatic clearance (CLH) from in vitro studies with liver microsomes correlated well with the observed in vivo clearance for both DIO and lean mice. The calculated oral bioavailability (F%) based on intrinsic hepatic clearance (C(LH, int)) predicted ~3 fold increase in F% for the DIO mice, which was comparable to the observed value. Collectively, these data suggest that the higher F% is most likely due to the lower first-pass effect in DIO mice. This study highlights the needs to take caution when extrapolating PK and exposure data from healthy animals to diseased animals in designing pharmacological studies.
Abstract Mitiglinide is a highly selective fast-acting anti-diabetic drug that inhibits pancreatic K ATP channels to induce insulin secretion. However, how mitiglinide binds K ATP channels remains unknown. Here, we show the cryo-EM structure of the SUR1 subunit in complex with mitiglinide. The structure reveals that mitiglinide binds inside the common insulin secretagogue-binding site in the transmembrane domain of SUR1, locking SUR1 in a NBD-separated inward-facing conformation. The detailed structural analysis uncovers the molecular basis of the high selectivity of mitiglinide.
To observe the effect of "Shugan Tiaoshen"(liver-soothing and mind-regulating) acupuncture on behavior reactions, opioid receptor expressions in the anterior cingulate cortex tissue and inflammatory factors in the serum in migraine rats, in order to explore its mechanism underlying improvement of migraine.In the first part of this study, forty male Wistar rats were randomized into control, model, routine acupuncture and "Shugan Tiaoshen" acupuncture groups (n=10/group), and in the second part, other 40 more male Wistar rats were randomized into low, medium and high dosage of blocker of μopioid receptor (OPRM)CTOP5 and PBS groups (n=10/group, for validating the involvement of opioid receptor in the effect of "Shugan Tiaoshen"). The migraine model was established by subcutaneous injection of glyceryl trinitrate. Routine acupuncture was applied to "Baihui" (GV20) and bilateral"Fengchi" (GB20), and "Shugan Tiaoshen" acupuncture applied to GV20, and bila-teral GB20, "Neiguan" (PC6) and "Taichong" (LR3), with the needles retained for 30 min. Behavior responses (head scratching, tail biting, cage climbing and number of going there and back) were scaled. Serum IL-1β, IL-6 and TNF-α were detected by ELISA, and the expression levels of opioid receptor μ, δ and κ (OPRM, OPRD, OPRK) mRNAs and proteins in the anterior cingulate cortex were detected by fluorescence quantitative PCR and Western blot separately. In the second part of this study, CTOP solution (5μL at concentrations of 20μg/μL,10μg/μL and 5μg/μL) or PBS was injected into the bilateral rostral portions of anterior cingulate cortex 30 min before every "Shugan Tiaoshen" acupuncture intervention, followed by observing the behavioral changes and assaying the contents of serum IL-1β, IL-6 and TNF-α.After modeling, the behavioral score, serum IL-1β, IL-6 and TNF-α contents were significantly increased in the model group relevant to the control group (P<0.05), and the beha-vioral score had no significant difference among the model and two acupuncture groups before intervention (P>0.05). Whereas the expression levels of OPRM, OPRD and OPRK mRNAs and proteins had a slight increase in the model group (P>0.05). After the intervention, the behavioral score, serum IL-1β, IL-6 and TNF-α contents were significantly decreased and the expression levels of OPRM, OPRD and OPRK mRNAs (2.150, 1.066 and 0.805 folds in the "Shugan Tiaoshen" group) and proteins (2.273, 0.901 and 0.893 folds in the "Shugan Tiaoshen" group) notably up-regulated in both "Shugan Tiaoshen" and routine acupuncture groups relevant to the model group (P<0.01, P<0.05), showing that the biggest up-regulation of mRNA expression was OPRM. Comparison between two acupuncture groups showed that the behavioral score, and serum IL-1β, IL-6 and TNF-α contents were significantly lower, and the expression levels of OPRM, OPRD and OPRK mRNAs and proteins obviously higher in the "Shugan Tiaoshen" group than those in the routine acupuncture group (P<0.01,P<0.05). Results of the second part of this study showed that after injection of antagonist CTOP of OPRM, the therapeutic effect of "Shugan Tiaoshen" acupuncture was weakened in the reduction of behavioral score and serum IL-1β, IL-6 and TNF-α contents, being minimal, moderate and maximum in the high, medium and low dose of antagonist relevant to PBS in sequence (P<0.05, P<0.01)."Shugan Tiaoshen" acupuncture can mitigate pain in migraine rats, which may be associated with its function in up-regulating the expressions of opioid receptors (especially OPRM), and in inhibiting inflammatory reaction in the anterior cingulate cortex.目的:观察疏肝调神针法对偏头痛大鼠行为学、血清炎性因子及前扣带皮层阿片受体表达水平的影响,探讨其介导阿片受体参与偏头痛治疗的机制。方法:Wistar大鼠按随机数字表法分为对照组10只、造模组30只。于大鼠颈后平坦区域皮下注射硝酸甘油制备偏头痛模型,造模成功的30只大鼠随机分为模型组、常规针刺组、疏肝调神组各10只。常规针刺组取“百会”、双侧“风池”,疏肝调神组取“百会”、双侧“风池”“内关”“太冲”,两组均留针30 min。干预前后评估大鼠行为学评分,干预后采用实时荧光定量PCR法、Western blot法检测大鼠脑组织前扣带皮层μ、δ和κ阿片受体(OPRM、OPRD、OPRK)mRNA及蛋白表达,ELISA法检测血清炎性因子白细胞介素(IL)-1β、IL-6、肿瘤坏死因子-α(TNF-α)含量。取另外40只造模成功的大鼠按随机数字表法分为抑制剂高、中、低剂量组及PBS组,分别于干预前颅内注射5 μg高、中、低浓度的疏肝调神组治疗后表达变化最明显的OPRM抑制剂,PBS组注射等量PBS溶液,之后各组均行疏肝调神针法干预;干预前后评估大鼠行为学评分,干预后ELISA法检测血清IL-1β、IL-6、TNF-α含量。结果:干预前其余3组大鼠行为学评分均高于对照组(P<0.01),干预后常规针刺组及疏肝调神组行为学评分均低于模型组(P<0.01),疏肝调神组低于常规针刺组(P<0.01)。模型组大鼠血清IL-1β、IL-6、TNF-α含量高于对照组(P<0.01),常规针刺组、疏肝调神组均低于模型组(P<0.05),疏肝调神组低于常规针刺组(P<0.05);模型组大鼠前扣带皮层中OPRM、OPRD、OPRK mRNA和蛋白表达水平均略高于对照组,但差异无统计学意义(P>0.05),常规针刺组及疏肝调神组均高于模型组(P<0.01,P<0.05),疏肝调神组高于常规针刺组(P<0.01,P<0.05)。与模型组比较,干预后疏肝调神组阿片受体中以OPRM上调倍数最大,由此回复实验选择OPRM抑制剂进行注射。干预后,高、中、低剂量组及PBS组行为学评分均低于同组干预前(P<0.01,P<0.05),且3个抑制剂组均高于PBS组(P<0.01,P<0.05);高、中、低剂量组血清IL-1β、IL-6、TNF-α含量均高于PBS组(P<0.01,P<0.05)。结论:疏肝调神针法通过上调阿片受体,尤其OPRM的表达,抑制炎性反应,从而发挥对偏头痛的治疗作用。.
BACKGROUND Myelin oligodendrocyte glycoprotein (MOG)-associated disease (MOGAD) is a recently described inflammatory demyelinating disease of the central nervous system (CNS), which needs to be distinguished from aquaporin-4 (AQP4)-IgG-positive neuromyelitis optica spectrum disorder (AQP4-IgG+NMOSD) and multiple sclerosis (MS). CASE REPORT A 42-year-old woman presenting with loss of vision due to optic neuritis was admitted to the Naval Medical Center in October 2022. She had optic disc edema, blurred visual margins, optic disc pallor, and deficient visual field in both eyes. Cranial magnetic resonance imaging (MRI) showed bilateral optic nerve thickening, tortuosity, and swelling, especially on the right side. Orbital MRI T2 sequence showed the typical "double track sign" change. The titers of MOG-IgG in CSF and serum were 1: 1 (+) and 1: 32 (+) separately, so MOGAD was diagnosed. The primary treatment was intravenous methylprednisolone for 2 weeks, after which the blurred vision improved and MRI showed the optic nerve lesions disappeared. She was discharged and oral corticosteroids were tapered gradually, and 1 month later, the symptom had vanished without recurrence, cranial MRI was normal, and MOG-IgG in CSF and serum were negative. Low-dose oral corticosteroids were continued for 6 months, with no relapse and normal cranial MRI, so we stopped corticosteroid therapy. At 1-year follow-up, the symptoms had not recurred. CONCLUSIONS A 42-year-old woman presented with loss of vision due to optic neuritis and positive antibody testing for MOG. MOGAD was diagnosed, and timely immunotherapy was effective.