Research progress and challenges in stem cell therapy for diabetic foot: Bibliometric analysis and perspectives

BACKGROUND Stem cell therapy has shown great potential for treating diabetic foot(DF).AIM To conduct a bibliometric analysis of studies on the use of stem cell therapy for DF over the past two decades,with the aim of depicting the current global research landscape,identifying the most influential research hotspots,and providing insights for future research directions.METHODS We searched the Web of Science Core Collection database for all relevant studies on the use of stem cell therapy in DF.Bibliometric analysis was carried out using CiteSpace,VOSviewer,and R(4.3.1)to identify the most notable studies.RESULTS A search was conducted to identify publications related to the use of stem cells for DF treatment.A total of 542 articles published from 2000 to 2023 were identified.The United States had published the most papers on this subject.In this field,Iran’s Shahid Beheshti University Medical Sciences demonstrated the highest productivity.Furthermore,Dr.Bayat from the same university has been an outstanding researcher in this field.Stem Cell Research&Therapy is the journal with the highest number of publications in this field.The main keywords were“diabetic foot ulcers,”“wound healing,”and“angiogenesis.”CONCLUSION This study systematically illustrated the advances in the use of stem cell therapy to treat DF over the past 23 years.Current research findings suggested that the hotspots in this field include stem cell dressings,exosomes,wound healing,and adipose-derived stem cells.Future research should also focus on the clinical translation of stem cell therapies for DF.

Serum calcium,albumin,globulin and matrix metalloproteinase-9 levels in acute cerebral infarction patients

BACKGROUND Hemorrhagic transformation(HT)is a common complication in patients with cerebral infarction.However,its pathogenesis is poorly understood.The knowledge of factors that may increase risk for HT may help in improving the safety of thrombolytic therapy.AIM To investigate the predictive value of serum calcium,albumin,globulin and matrix metalloproteinase-9(MMP-9)levels for HT after intravenous thrombolysis(IVT)in patients with acute cerebral infarction.METHODS Five hundred patients with acute cerebral infarction who received IVT with alteplase within 4.5 h after the onset of disease between January 2018 and January 2021 at our hospital were selected as the study subjects.They were divided into groups based on computed tomography scan results of the brain made within 36 h after thrombolysis.Forty patients with HT were enrolled in an observation group and 460 patients without HT were enrolled in a control group.Serum calcium,albumin,globulin and MMP-9 levels were compared between the two groups.Regression analysis was used to discuss the relationship between these indices and HT.RESULTS The previous history of hypertension,diabetes,atrial fibrillation,cerebrovascular diseases,smoking and alcohol intake were not associated with HT after IVT in patients with acute cerebral infarction(all P>0.05).The National Institutes of Health stroke scale(NHISS)score was associated with HT after IVT in patients with acute cerebral infarction(P<0.05).The serum calcium and albumin levels were lower in the observation group than in the control group(all P<0.05).The levels of globulin and MMP-9 were significantly higher in the observation group than in the control group(all P<0.05).Logistic regression analysis showed that NHISS score,serum calcium,albumin,globulins and MMP-9 were independent factors influencing the occurrence of HT following IVT in patients with cerebral infarction(P<0.05).CONCLUSION Serum calcium,albumin,globulin and MMP-9 levels are risk factors for HT after IVT in patients with acute cerebral infarction.Moreover,NHISS score can be used as a predictor of post-thrombolytic HT.

A preliminary study on the teratogenesis of dexamethasone and the preventive effect of vitamin B_(12 )on murine embryonic palatal shelf fusion in vitro

Excessive dexamethasone (Dex) administrated into pregnant mice during critical periods of palatal development can produce a high incidence of cleft palate. Its mechanisms remain unknown. Vitamin B12 has been shown to antagonize the tera- togenic effects of Dex, which, however, remains controversial. In this study, we investigated the effects of Dex and vitamin B12 on murine embryonic palatal shelf fusion using organ culture of murine embryonic shelves. The explanted palatal shelves on em- bryonic day 14 (E14) were cultured for 24, 48, 72 or 96 h in different concentrations of Dex and/or vitamin B12. The palatal shelves were examined histologically for the morphological alterations on the medial edge epithelium (MEE) and fusion rates among different groups. It was found that the palatal shelves were not fused at 72 h or less of culture in Dex group, while they were completely fused in the control and vitamin B12-treated groups at 72 and 96 h, respectively. The MEE still existed and proliferated. In Dex+vitamin B12 group the palatal shelves were fused at each time point in a similar rate to controls. These results may suggest that Dex causes teratogenesis of murine embryonic palatal shelves and vitamin B12 prevents the teratogenic effect of Dex on palatogenesis on murine embryos in vitro.

INVERSE OPALINE STRUCTURE TITANIA PHOTONIC CRYSTALS BY FUNCTIONALLY MODIFIED COLLOIDAL CRYSTALS TEMPLATING

Ordered macroporous titania photonic crystals (PCs) and photonic balls were fabricated by functional modified polymer colloidal crystals. The TiO2 PCs and balls formed through this method exhibit no cracks and lacunae in large areas on their surface and their inner structures.

Flow pattern analysis of linear gradient flow distribution

This paper uses the Oseen transformation to solve the differential equations governing motion of the vertical linear gradient flow distribution close to a wall surface.The Navier-Stokes equations are used to consider the inertia term along the flow direction.A novel contour integral method is used to solve the complex Airy function. The boundary conditions of linear gradient flow distribution for finite problems are determined. The vorticity function, the pressure function, and the turbulent velocity profiles are provided,and the stability of particle trajectories is studied. An Lx-function form of the third derivative circulation is used to to simplify the solution. Theoretical results are compared with the experimental measurements with satisfactory agreement.

Interaction Mechanism of Nano-silicon Dioxide Modified by Poly（amidoamine） Dendrimers

获得卓见进Si+( SC )离子的附件(认为是客人)到最低产生， 终止NH2 poly ( amidoamine )( PAMAM ) dendrimers (认为是主人)在液体阶段，密度功能的理论被用来调查主人客人建筑群的结构和 energetics 。结构和 energetics 上的溶剂的效果也被调查。到 PAMAM 的离子界限的各种各样的起始的配置被测试，并且二稳定的 conformers 被发现即，类型 A (Si+ 被绑在胺地点) 并且 C (Si+ 被绑在酰胺地点) 。类型 A 和 C 由于罪恶的化学契约形成是最稳定的 ? 敯浨琠瑩慲楴湯 ?? 慲? 桰瑯敯敬瑣潲 ? 灳 ' 虪?愠摮 ? 畯楲牥琠慲獮潦浲椠普慲敲 ? 灳 '

Application of endoscopic submucosal dissection in duodenal space-occupying lesions

BACKGROUNDEndoscopic submucosal dissection (ESD) has been advocated by digestiveendoscopists because of its comparable therapeutic effect to surgery, reducedtrauma, faster recovery, and fewer complications. However, ESD for lesions of theduodenum is more challenging than those occurring at other levels of thegastrointestinal tract due to the thin intestinal wall of the duodenum, narrowintestinal space, rich peripheral blood flow, proximity to vital organs, and highrisks of critical adverse events including intraoperative and delayed bleeding andperforation. Because of the low prevalence of the disease and the high risks ofsevere adverse events, successful ESD for lesions of the duodenum has rarelybeen reported in recent years.AIM To investigate the efficacy and safety of ESD in the treatment of duodenal spaceoccupyinglesions.METHODS Clinical data of 24 cases of duodenal lesions treated by ESD at the DigestiveEndoscopy Center of the Affiliated Hospital of Qingdao University from January2016 to December 2019 were retrospectively analyzed.RESULTS All of the 24 cases from 23 patients underwent ESD treatment for duodenal spaceoccupyinglesions under general anesthesia, including 15 male and 8 femalepatients, with a mean age of 58.5 (32.0-74.0) years. There were 12 lesions (50%) inthe duodenal bulb, 9 (37.5%) in the descending part, and 3 (12.5%) in the ball descending junction. The mean diameter of the lesion was 12.75 (range, 11-22)mm. Thirteen lesions originated from the mucosa, of which 4 were low-gradeintraepithelial neoplasia, 3 were hyperplastic polyps, 2 were chronic mucositis, 2were adenomatous hyperplasia, 1 was high-grade intraepithelial neoplasia, and 1was tubular adenoma. Eleven lesions were in the submucosa, including 5neuroendocrine neoplasms, 2 cases of ectopic pancreas, 1 stromal tumor, 1leiomyoma, 1 submucosal duodenal adenoma, and 1 case of submucosal lymphfollicular hyperplasia. The intraoperative perforation rate was 20.8% (5/24),including 4 submucosal protuberant lesions and 1 depressed lesion. The meanlength of hospital stay was 5.7 (range, 3-10) d, and the average follow-up time was25.8 (range, 3.0–50.0) mo. No residual disease or recurrence was found in allpatients, and no complications, such as infection and stenosis, were found duringthe follow-up period.CONCLUSION ESD is safe and effective in the treatment of duodenal lesions;however, theendoscopists should pay more attention to the preoperative preparation,intraoperative skills, and postoperative treatment.

Gastric pyloric gland adenoma resembling a submucosal tumor:A case report

BACKGROUND Pyloric gland adenoma(PGA)is a recently described and rare tumor.Submucosal tumor(SMT)-like PGA is more difficult to diagnose and differentiate from other submucosal lesions.CASE SUMMARY We present the case of a 69-year-old man with a 10 mm SMT-like elevated lesion with an opening in the upper part of the gastric body,referred to our hospital for further endoscopic treatment.Magnifying endoscopy with narrow-band imaging,endoscopic ultrasonography,and complete endoscopic submucosal dissection were performed on the patient.Histopathological findings revealed tightly packed tubular glands lined with cuboidal or columnar cells that had round-tooval nuclei containing occasional prominent nucleoli and an eosinophilic cytoplasm similar to that in non-neoplastic gastric pyloric glands.Additionally,immunohistochemical analysis showed positive staining for both mucin 5AC and mucin 6.Therefore,we arrived at the final diagnosis of gastric PGA.Although there was no apparent malignant component in this tumor,PGA has been considered a precancerous disease with a high risk of transformation into adenocarcinoma.CONCLUSION PGA should be considered when detecting gastric SMT-like lesions.Physicians and pathologists should focus on PGA due to its malignant potential.

Effects of perioperative rosuvastatin on postoperative delirium in elderly patients:A randomized,double-blind,and placebo-controlled trial

BACKGROUND Experimental evidence has indicated the benefits of statins for the treatment of postoperative delirium.Previously,clinical trials did not reach definite conclusions on the effects of statins on delirium.Some clinical trials have indicated that statins reduce postoperative delirium and improve outcomes,while some studies have reported negative results.AIM To evaluate whether perioperative rosuvastatin treatment reduces the incidence of delirium and improves clinical outcomes.METHODS This randomized,double-blind,and placebo-controlled trial was conducted in a single center in Jiangsu,China.This study enrolled patients aged greater than 60 years who received general anesthesia during elective operations and provided informed consent.A computer-generated randomization sequence(in a 1:1 ratio)was used to randomly assign patients to receive either rosuvastatin(40 mg/d)or placebo.Participants,care providers,and investigators were all masked to group assignments.The primary endpoint was the incidence of delirium,which was assessed twice daily with the Confusion Assessment Method during the first 7 postoperative days.Analyses were performed on intention-to-treat and safety populations.RESULTS Between January 1,2017 and January 1,2020,3512 patients were assessed.A total of 821 patients were randomly assigned to receive either placebo(n=411)or rosuvastatin(n=410).The incidence of postoperative delirium was significantly lower in the rosuvastatin group[23(5.6%)of 410 patients]than in the placebo group{42(13.5%)of 411 patients[odds ratios(OR)=0.522,95%confidence interval(CI):0.308-0.885;P<0.05]}.No significant difference in 30-d all-cause mortality(6.1%vs 8.7%,OR=0.67,95%CI:0.39-1.2,P=0.147)was observed between the two groups.Rosuvastatin decreased the hospitalization time(13.8±2.5 vs 14.2±2.8,P=0.03)and hospitalization expenses(9.3±2.5 vs 9.8±2.9,P=0.007).No significant differences in abnormal liver enzymes(9.0%vs 7.1%,OR=1.307,95%CI:0.787-2.169,P=0.30)or rhabdomyolysis(0.73%vs 0.24%,OR=3.020,95%CI:0.31-29.2,P=0.37)were observed between the two groups.CONCLUSION The current study suggests that perioperative rosuvastatin treatment reduces the incidence of delirium after an elective operation under general anesthesia.However,the evidence does not reveal that rosuvastatin improves clinical outcomes.The therapy is safe.Further investigation is necessary to fully understand the potential usefulness of rosuvastatin in elderly patients.

Predictive factors for the post embolization fever after transcatheter arterial chemoembolization in hepatocellular carcinoma patients:a single center study in China

Background and Objectives:Post embolization fever(PEF)is one of the most common symptoms of post embolization syndrome(PES).This study aimed to determine and validate a model to predict PEF after transcatheter arterial chemoembolization(TACE)in hepatocellular carcinoma(HCC)patients.Methods:Clinical data of HCC patients who underwent TACE with platinum was retrospectively collected in our center from 2017 to 2018.Predictive factors were screened by multivariate logistic regression.The accuracy and discriminative ability of these factors were evaluated by the receiver operating characteristic(ROC)curve using the derivation cohort and an independent validation cohort.Results:A total of 367 patients were included,of whom 53(14.4%)patients had PEF.Fevers were detected in 44 of 252 patients in the derivation cohort and 9 of 115 patients in the validation cohort.Predictors for PEF identified in multivariate logistic regression included Lipiodol emulsion dose(OR,1.081;95%CI,1.006-1.162),number of concomitants uses of hepatoprotectants(OR,0.619;95%CI,0.419-0.914),K+levels(OR,2.992;95%CI,1.225-7.308),and albumin-bilirubin(ALBI)grade(OR,2.249;95%CI,1.040-4.862).Furthermore,the area under the ROC curve of the derivation and validation cohorts were 0.798 and 0.874,respectively.Conclusions:Our study demonstrated that Lipiodol emulsion dose,number of concomitant uses of hepatoprotectants,K+levels,and ALBI grade are independent risk factors for PEF.The multivariate logistic model of these factors shows a discriminative ability to predict PEF in the patients who underwent TACE.

角膜基质透镜在角膜溃疡或穿孔修复中的应用

目的:研究由全飞秒激光SMILE手术所得的角膜基质透镜作为角膜移植材料治疗角膜溃疡的临床疗效。方法:回顾性病例研究。收集本院2017-01/06角膜溃疡患者6例6眼,其中细菌性、真菌性、深层异物伴感染各1例1眼,角膜穿孔3例3眼。采用由全飞秒激光SMILE手术所得的角膜基质透镜作为角膜移植的材料进行修复手术,确保植片与角膜层间无空气间隙。术后随访1~6(平均3.71±1.56)mo,观察手术前后视力、角膜移植物存活情况及术后并发症发生情况等。结果:所有患者均在控制感染下顺利完成手术,无术中并发症。术后所有角膜植片透明。末次随访时,患者最佳矫正视力(best corrected visual acuity,BCVA)较术前明显改善(0.48±0.12 vs 1.50±0.08),差异具有统计学意义(P<0.01)。结论:来源于全飞秒激光屈光手术的角膜基质透镜用于角膜溃疡修复是安全有效的,但植片的远期疗效尚需进一步观察。

热休克蛋白65对小鼠溃疡性结肠炎的作用机制研究

目的探讨热休克蛋白65(HSP65)对小鼠溃疡性结肠炎(UC)的作用及机制。方法选择C57BL/6小鼠,应用葡聚糖硫酸钠法复制UC模型。6只正常小鼠为正常对照组(A组),48只UC小鼠随机分成模型对照组(B组)、低剂量组(C组)、中剂量组(D组)及高剂量组(E组),每组12只。A组和B组小鼠灌胃给予磷酸盐缓冲液(PBS),C组、D组、E组小鼠分别灌胃给予HSP65,剂量分别是0.5、2.5及5.0mg/kg体重。隔天灌胃1次,共7次,末次灌胃2d后,麻醉处死小鼠。计算小鼠疾病活动指数(DAI)。取小鼠结肠中段组织,HE染色镜检并计算组织病理评分。取小鼠血液、脾脏和肠系膜淋巴结,分离有核细胞后采用流式细胞术检测调节性T细胞(Treg)活化情况。结果 HSP65蛋白治疗UC小鼠14d,B、C、D及E组小鼠的DAI分别为(3.66±0.39)、(3.07±0.15)、(1.50±0.43)和(0.83±0.31),C组、D组、E组小鼠DAI变化趋势有差异(P<0.05);C组、D组和E组小鼠结肠组织病理评分均低于B组小鼠(P<0.05);E组小鼠结肠组织病理评分低于C组和D组(P<0.05),D组小鼠结肠组织病理评分低于C组(P<0.05);与未治疗的B组比较,C组、D组、E组小鼠肠系膜淋巴结中的Treg细胞比例均高于B组(P?<0.05)。结论 HSP65蛋白可以缓解小鼠溃疡性结肠炎,其机制可能是通过激活小鼠肠系膜淋巴结中的静止Treg细胞,使得活化Treg细胞比例增加,再通过活化Treg细胞发挥抑制肠道炎症反应作用。

美国高等学校科研软环境探析

分析了美国高校建设科研软环境的运行机制:校长负责制是前提;教师聘用制是保证;绩效评估制是命脉。阐述了美国高校通过营造学术氛围,提高科研管理与服务的效率和水平,科研人员跨部门和跨国开放型竞争流动等机制建设科研软环境。

囊袋张力环的临床应用研究

囊袋张力环作为一种囊袋内填充装置,在白内障手术中起着重要的作用。囊袋张力环设计的初衷是维持囊袋的圆形轮廓、提高手术安全性,之后发现它在抑制后囊膜混浊与囊袋收缩、增强人工晶状体稳定性等方面亦有较好效果。经过近30a的改良,囊袋张力环衍生出多种类型,临床应用范围逐渐扩展,尤其是应用于复杂白内障手术,可以降低术中风险及提升术后效果。本文总结了囊袋张力环临床应用的植入时机、适应证和并发症,并对近年来囊袋张力环的临床应用进展进行简要综述。

不同浓度阿托品延缓近视儿童等效球镜度及眼轴长度效果的Meta分析

目的:系统评价眼用0.01%、0.025%和0.05%阿托品对于近视儿童等效球镜度及眼轴长度的影响。方法:检索PubMed、Embase、Cochrane Library、Web of Science、中国知网、万方数据库、维普网、中国生物医学文献数据库中从建库至2022-05期间发表的关于0.01%、0.025%和0.05%阿托品进行近视控制的研究。使用Cochrane手册对纳入文献进行偏倚风险评价及质量评价,并使用Revman 5.4软件进行Meta分析,利用STATA12.0软件检测发表偏倚。结果:共计纳入6篇文献1 239眼,其中5项为随机对照试验,1项为病例对照研究。Meta分析显示,0.025%阿托品对SE及AL的抑制效果好于0.01%阿托品(SE:WMD=-0.15,95%CI:-0.23~-0.06,P<0.001;AL:WMD=0.07,95%CI:0.03~0.10,P<0.001)。0.05%阿托品对SE及AL抑制效果好于0.01%阿托品(SE:WMD=-0.35,95%CI:-0.44~-0.26,P<0.001;AL:WMD=0.16,95%CI:0.12~0.20,P<0.001)。0.05%阿托品对SE及AL增加的抑制效果好于0.025%阿托品(SE:WMD=-0.20,95%CI:-0.28~-0.11,P<0.001;AL:WMD=0.09,95%CI:0.06~0.12,P<0.001)。结论:0.05%阿托品对SE及AL的控制效果优于0.025%及0.01%阿托品,但长期使用的副作用仍有待进一步观察。

Honokiol:a promising small molecular weight natural agent for the growth inhibition of oral squamous cell carcinoma cells

Honokiol (HNK) is a small organic molecule purified from magnolia species and has demonstrated anticancer activities in a variety of cancer cell lines; however, its effect on oral squamous cell carcinoma (OSCC) cells is unknown. We investigated the antitumor activities of HNK on OSCC cells in vitro for the first time. The inhibitory effects of HNK on the growth and proliferation of OSCC cells were demonstrated via in vitro 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and propidium iodide (PI) assays, and the apoptotic cells were investigated by the observation of morphological changes and detection of DNA fragmentation via PI, TdT-mediated dUTP-biotin nick end labeling (TUNEL), and DNA ladder assays, as well as flow cytometry assay. The results showed that HNK inhibited the growth and proliferation of OSCC cells in vitro in a time and dose-dependent manner. The inhibitory effect was associated with the cell apoptosis induced by HNK, evidenced by the morphological features of apoptotic cells, TUNEL-positive cells and a degradation of chromosomal DNA into small internucleosomal fragments. The study also demonstrated here that the inhibition or apoptosis mediated by 15 μg·mL-1 or 20 μg·mL-1 of HNK were more stronger compared with those of 20 μg·mL-1 5-fluorouracil (5-Fu, the control) applied to OSCC cells, when the ratio of OSCC cell numbers were measured between the treatment of different concentrations of HNK to the 5-Fu treatment for 48 h. HNK is a promising compound that can be potentially used as a novel treatment agent for human OSCC.

Genetic, environmental and other risk factors for progression of retinitis pigmentosa

Retinitis pigmentosa(RP) is a commonly inherited disease of the retina, which is characterized by progressive loss of visual function due to specific genetic mutations. There are many risk factors that may have effect on the progression of RP, such as inheritance patterns, genotype, gender, age, smoking, physical activity, and other demographic and environmental factors. Baseline visual field conditions, changes of ellipsoid zone, photoreceptor layer thickness, and choroidal structure are reported to be the phenotype risk factors for RP progression. Moreover, aqueous flare and high-sensitivity C-reactive protein are probable inflammation biomarkers for assessing the progression of RP. Increased oxidative stress is considered to be one of the potential factors for the existence of RP. The risk factors can be combined to form a corresponding prediction model to predict disease progression. This review is to summarize the current literature that studies the genetic, environmental, phenotypic, demographic, inflammatory and other risk factors of RP progression and discuss the most reliable risk factors that could provide predictive models.

Non-monotonic influence of a magnetic field on the electrochemical behavior of Fe_(78)Si_9B_(13) glassy alloy in NaOH and NaCl solutions

The corrosion behavior and microstructure of Fe78Si9B13 glassy alloy in NaOH and NaCl solutions under a 0.02-T magnetic field were investigated through electrochemical testing and scanning electron microscopy(SEM). The current-density prepeak(PP) in the anodic polarization curves in low-concentration NaOH solutions(classified as type I) tends to disappear when the NaOH concentration is increased to 0.4 mol/L and the magnetic field is applied. Under the magnetic field, the height of the second current-density peak is increased in low-concentration NaOH solutions(type I) but decreased in high-concentration NaOH solutions(type II). The non-monotonic effect of the magnetic field was similarly observed in the case of polarization curves of samples measured in NaCl solutions. Ring-like corroded patterns and round pits are easily formed under the magnetic field in NaOH and NaCl solutions. These experimental results were discussed in terms of the magnetohydrodynamic(MHD) effect.

Early colon cancer with enteropathy-associated T-cell lymphoma involving the whole gastrointestinal tract:A case report

BACKGROUND Enteropathy-associated T-cell lymphoma(EATL)is a rare invasive lymphoma derived from gastrointestinal epithelial T lymphocytes.EATL involving the whole gastrointestinal tract accompanied with early colon cancer is extremely rare.CASE SUMMARY We present the case of a 67-year-old man with diarrhea for more than 5 mo whose colonoscopy in another hospital showed multiple colonic polyps,which indicated moderate to severe dysplasia and focal early cancer.Therefore,he was referred to our hospital for further endoscopic treatment.Colonoscopy after admission showed that the mucosa of the terminal ileum and the entire colon were slightly swollen and finely granular.Endoscopic mucosal resection was performed for colonic polyps located in the liver flexure of the colon and descending colon,respectively.Histopathological findings revealed diffuse infiltration of mediumsized lymphoid cells in the colonic mucosa and visible lymphoepithelial lesions.The histopathology of the polyp in the descending colon indicated moderately differentiated adenocarcinoma limited to the mucosa with negative resection margins.Additionally,immunohistochemical analysis showed positive staining for CD7 and CD8.Therefore,we arrived at a diagnosis of EATL with early colon cancer.Subsequently,the patient was transferred to the hematology department for chemotherapy.The patient’s diarrhea was not significantly relieved after receiving chemotherapy,and he ultimately died of severe myelosuppression.CONCLUSION EATL should be considered in unexplained chronic diarrhea.EATL progresses rapidly with a poor prognosis,especially when accompanied with early colon cancer.

Learning Unitary Transformation by Quantum Machine Learning Model

Quantum machine learning(QML)is a rapidly rising research eld that incorporates ideas from quantum computing and machine learning to develop emerging tools for scientic research and improving data processing.How to efciently control or manipulate the quantum system is a fundamental and vexing problem in quantum computing.It can be described as learning or approximating a unitary operator.Since the success of the hybrid-based quantum machine learning model proposed in recent years,we investigate to apply the techniques from QML to tackle this problem.Based on the Choi–Jamiołkowski isomorphism in quantum computing,we transfer the original problem of learning a unitary operator to a min–max optimization problem which can also be viewed as a quantum generative adversarial network.Besides,we select the spectral norm between the target and generated unitary operators as the regularization term in the loss function.Inspired by the hybrid quantum-classical framework widely used in quantum machine learning,we employ the variational quantum circuit and gradient descent based optimizers to solve the min-max optimization problem.In our numerical experiments,the results imply that our proposed method can successfully approximate the desired unitary operator and dramatically reduce the number of quantum gates of the traditional approach.The average delity between the states that are produced by applying target and generated unitary on random input states is around 0.997.