Collagen-based materials, renowned for their biocompatibility and minimal immunogenicity, serve as exemplary substrates in a myriad of biomedical applications. Collagen-based micro/nanogels, in particular, are valued for their increased surface area, tunable degradation rates, and ability to facilitate targeted drug delivery, making them instrumental in advanced therapeutics and tissue engineering endeavors. Although extensive reviews on micro/nanogels exist, they tend to cover a wide range of biomaterials and lack a specific focus on collagen-based materials. The current review offers an in-depth look into the manufacturing technologies, drug release mechanisms, and biomedical applications of collagen-based micro/nanogels to address this gap. First, we provide an overview of the synthetic strategies that allow the precise control of the size, shape, and mechanical strength of these collagen-based micro/nanogels by controlling the degree of cross-linking of the materials. These properties are crucial for their performance in biomedical applications. We then highlight the environmental responsiveness of these collagen-based micro/nanogels, particularly their sensitivity to enzymes and pH, which enables controlled drug release under various pathological conditions. The discussion then expands to include their applications in cancer therapy, antimicrobial treatments, bone tissue repair, and imaging diagnosis, emphasizing their versatility and potential in these critical areas. The challenges and future perspectives of collagen-based micro/nanogels in the field are discussed at the end of the review, with an emphasis on the translation to clinical practice. This comprehensive review serves as a valuable resource for researchers, clinicians, and scientists alike, providing insights into the current state and future directions of collagen-based micro/nanogel research and development.
Collagen/chemistry* ; Drug Delivery Systems/methods* ; Humans ; Tissue Engineering/methods* ; Animals ; Biocompatible Materials/chemistry*

Methods:From February 2018 to January 2022, the clinical data of 1 123 patients who underwent Starclose vascular closure device, Angio-Seal and Exoseal vascular occlusion devices and Perclose ProGlide vascular suture device at femoral artery puncture hemostasis after neuro-intervention, in the Department of Interventional Radiology (Eastern District), The First Affiliated Hospital of Zhengzhou University, were retrospectively analyzed. The patients were divided into three groups based on the intervention method: the closure group (Starclose, n=271), the occlusion group (Angio-Seal, n=327 and Exoseal, n=352) and the suture group (ProGlide, n=173). Next, the hemostatic efficacy and complications associated with the three devices were analyzed and compared. Additionally, regression analysis was conducted to identify any relevant factors that may contribute to complications. Results:Three vascular hemostatic devices demonstrated effective hemostasis and the success rate were 92.6% in the closure group (Starclose), 93.4% in the occlusion group (Angio-Seal 93.0% and Exoseal 93.8%) and 89.6% in the suture group (ProGlide). There was no statistically significant difference( χ2=3.026, P=0.388). Single or multiple complications were observed in 102 patients (9.1%), including local oozing (16 cases in the closure group, 39 cases in the occlusion group, 13 cases in the suture group), local hematoma (14 cases in the closure group, 31 cases in the occlusion group, 11 cases in the suture group), pseudoaneurysm (13 cases in the closure group, 35 cases in the occlusion group, 10 cases in the suture group), local infection (2 cases in the closure group, 3 cases in the occlusion group, 1 case in the suture group). There were no statistically significant differences ( P>0.05). Moreover, serious complications such as femoral artery occlusion, embolus shedding and permanent nerve injury weren′t observed in the three groups. Multivariate logistic regression analysis revealed that overweight ( OR=1.562,95% CI 1.023—2.385, P=0.039), femoral artery with calcified plaque ( OR=1.934,95% CI 1.172-3.189, P=0.010), combined use of multiple antiplatelet drugs ( OR=1.769,95% CI 1.103—2.839, P=0.018), use of an 8F sheath( OR=2.824,95% CI 1.406—5.671, P=0.004) and the operator′s proficiency ( OR=0.508,95% CI 0.328—0.788, P=0.002) were the independent factors influencing complications, of which the first four were identified as risk-promoting factors for complications while the operator′s rich experience and high proficiency were the protective factors. Conclusions:Three hemostatic devices demonstrate effective hemostasis and comparable rates of complications at femoral artery puncture hemostasis after neuro-intervention. Overweight, femoral artery with calcified plaque, combined use of multiple antiplatelet drugs, use of an 8 F sheath and the operator′s proficiency were independent factors influencing complications.Ojective:To investigate the efficacy and complications associated with vascular suture, closure and occlusion devices at femoral artery puncture hemostasis after neuro-intervention.

Objective:To summarize the imaging features of severe unilateral transverse sinus and sigmoid sinus thromboses, and evaluate the efficacy and safety of intravascular interventional therapy in them.Methods:Thirty-seven patients with severe unilateral transverse sinus and sigmoid sinus thromboses clinically mainly manifested as intracranial hypertension and accepted endovascular intervention in Department of Interventional Radiology, First Affiliated Hospital of Zhengzhou University from June 2012 to September 2022 were chosen; their clinical data were retrospectively analyzed and imaging features were summarized. Short-term efficacy was evaluated according to blood flow restoration degrees and pressure gradient reduction in the occlusive sinus and modified neurological symptoms before and after endovascular intervention. Hospitalized complications were observed; safety and long-term efficacy were evaluated according to postoperative clinical follow-up and imaging results 6-12 months after endovascular intervention.Results:(1) Preoperative brain MRI and (or) CT showed different degrees of swelling of the brain tissues, with the affected side as the target; mixed signals/density shadow could be seen in the blocked transverse sinus and sigmoid sinus; venous cerebral infarction or post-infarction cerebral hemorrhage could be combined in some patients. MRV, CTV and DSA showed poor or completely occluded transverse sinus and sigmoid sinus while normal in the contralateral side; obvious thrombus filling-defect was observed in the occluded venous sinus after mechanical thrombolysis. (2) Occlusive sinus blood flow was restored in all patients after endovascular intervention, and pressure gradient of the occlusive segment decreased from (16.6±3.3) mmHg before to (2.8±0.8) mmHg after endovascular intervention. Before discharge, clinical symptoms of all patients were significantly improved (modified Rankin scale [mRS] scores of 0 in 30 patients, 1 in 5 patients, 2 in 1 patient and 3 in 1 patient), and 2 patients had unilateral limb movement disorder (muscle strength grading III and IV, respectively). All patients received clinical follow-up for (9.6±3.0) months. At the last follow-up, neurological function obviously improved compared with that before endovascular intervention, without new neurosystem-related symptoms (mRS scores of 0 in 30 patients, 1 in 6, and 2 in 1 patient). In 34 patients received MRV or DSA follow-up, 28 had complete recanalization of occlusive sinus and 6 had partial recanalization, without obvious stenosis or recurrent occlusion.Conclusions:Severe unilateral transverse sinus and sigmoid sinus thrombosis can cause local intracranial venous blood stasis, and then cause "increased regional venous sinus pressure", which is manifested as unilateral brain tissue swelling and even venous cerebral infarction or post-infarction cerebral hemorrhage. Early diagnosis and endovascular intervention can obviously improve the prognosis of these patients, enjoying good safety.

Objective:Differences between randomized controlled trial (RCT) results and real world study (RWS) results may not represent a true efficacy-effectiveness gap because efficacy-effectiveness gap estimates may be biased when RWS and RCT differ significantly in study design or when there is bias in RWS result estimation. Secondly, when there is an efficacy- effectiveness gap, it should not treat every patient the same way but assess the real-world factors influencing the intervention's effectiveness and identify the subgroup likely to achieve the desired effect.Methods:Six databases (PubMed, Embase, Web of Science, CNKI, Wanfang Data, and VIP) were searched up to 31 st December 2022 with detailed search strategies. A scoping review method was used to integrate and qualitatively describe the included literature inductively. Results:Ten articles were included to discuss how to use the RCT research protocol as a template to develop the corresponding RWS research protocol. Moreover, based on correctly estimating the efficacy-effectiveness gap, evaluate the intervention effect in the patient subgroup to confirm the subgroup that can achieve the expected benefit-risk ratio to bridge the efficacy-effectiveness gap.Conclusion:Using real-world data to simulate key features of randomized controlled clinical trial study design can improve the authenticity and effectiveness of study results and bridge the efficacy-effectiveness gap.

Objective:Randomized controlled trials (RCT) usually have strict implementation criteria. The included subjects' characteristics of the conditions for the intervention implementation are quite different from the actual clinical environment, resulting in discrepancies between the risk-benefit of interventions in actual clinical use and the risk-benefit shown in RCT. Therefore, some methods are needed to enhance the extrapolation of RCT results to evaluate the real effects of drugs in real people and clinical practice settings.Methods:Six databases (PubMed, Embase, Web of Science, CNKI, Wanfang Data, and VIP) were searched up to 31 st December 2022 with detailed search strategies. A scoping review method was used to integrate and qualitatively describe the included literature inductively. Results:A total of 12 articles were included. Three methods in the included literature focused on: ①improving the design of traditional RCT to increase population representation; ②combining RCT Data with real-world data (RWD) for analysis;③calibrating RCT results according to real-world patient characteristics.Conclusions:Improving the design of RCT to enhance the population representation can improve the extrapolation of the results of RCT. Combining RCT data with RWD can give full play to the advantages of data from different sources; the results of the RCT were calibrated against real-world population characteristics so that the effects of interventions in real-world patient populations can be predicted.

Objective:To establish a scientific and standardized evaluation index system of neonatal breastfeeding nursing quality under the state of mother-infant separation, in order to provide a tool for the detection and management of neonatal breastfeeding nursing quality under mother-infant separation, so as to promote the implementation of breastfeeding in China.Methods:A systematic and comprehensive search of Chinese and English databases was conducted to collect guidelines on neonatal breastfeeding in the state of mother-infant separation. Based on the "structure-process - result" three-dimensional quality structure model, the preliminary draft of evaluation indexes of neonatal breastfeeding nursing quality in the state of mother-infant separation was formed. The evaluation indexes of neonatal breastfeeding nursing quality in the state of mother-infant separation were constructed by Delphi expert correspondence method from July to October, 2023.Results:The effective recovery rates were 95.83% (23/24) and 91.30% (21/23), respectively. The expert authority coefficients were 0.895 and 0.870, respectively. The Kendall harmony coefficients of the whole index were 0.134 and 0.178 (both P<0.01), respectively. The final evaluation index system of neonatal breastfeeding nursing quality under the state of mother-infant separation includes 3 first-level indicators, 18 second-level indicators and 82 third-level indicators. Conclusions:The evaluation index system of neonatal breastfeeding nursing quality in the state of mother-infant separation established in this study is highly scientific and reliable, highlighting the characteristics of neonatal breastfeeding nursing work in the state of mother-infant separation, and can provide a reference for the evaluation of neonatal breastfeeding nursing quality in the state of mother-infant separation.

Objective:To assess the efficacy and safety of overlapping braided carotid artery stent (Wallstent) implantation in large extracranial internal carotid artery aneurysms (15 mm≤diameter<25 mm) and giant ones (diameter≥25 mm).Methods:A retrospective study was performed; the clinical data of 23 patients with large or giant extracranial internal carotid artery aneurysms accepted overlapping Wallstent stent implantation in Department of Interventional Radiology, First Affiliated Hospital of Zhengzhou University from August 2015 to June 2023 were collected. Immediately after implantation, DSA was used to evaluate the retention of contrast agent within the aneurysms and high-resolution C-arm CT (HR-CBCT) was used to detect the apposition between the two stents and between the stents and inner wall of the blood vessel. Perioperative complications were recorded. Clinical follow-up was performed bi-monthly via outpatient visits or telephone, and modified Rankin scale (mRS) was used to assess the prognoses (mRS scores of 0-2 as good prognosis) at the last follow-up; aneurysm occlusion was evaluated in a 6-month follow-up by DSA and in-stent restenosis in a final imaging follow-up by DSA or CTA according to the OKM grading. Results:Twenty-two patients had successful overlapping implantation of 2 Wallstent stents; blood flow was restricted in one patient due to carotid artery dissection at the distal end of the aneurysm during stent implantation and restored after a Neuroform EZ stent and 2 Wallstent stent implantation from the distal-proximal lesion; technical success rate of 95.7% (22/23) was obtained. DSA immediately after implantation showed obvious contrast medium retention in all aneurysms. HR-CBCT indicated good stent apposition in 21 patients and mild incomplete stent apposition in 2. Clinical follow-up was finished in 23 patients, ranged 6-31 months (mean 11.5±6.3 months); all patients had good prognosis at the last follow-up. Imaging follow-up, including at least once DSA, was conducted for all patients, with intervals ranging from 6 to 15 months (mean 10.4±3.4 months); DSA 6 months after implantation showed complete aneurysm occlusion in 19 patients (OKM grading D) and a bit of residual contrast in 4 patients (OKM grading C); final imaging follow-up (DSA in 2 and CTA in 21) revealed in-stent stenosis in 2 patients (stenosis rates of 51% and 87%) with obvious improved stenosis after balloon angioplasty and patent stents in 21 patients without evidence of aneurysm opacification.Conclusion:Overlapping braided carotid artery stent (Wallstent) implantation is an effective and safe approach for managing large or giant extracranial carotid artery aneurysms.

Objective To investigate the role of nitric oxide synthase(NOS)in the regulation of myocardial ischemia-reperfusion(IR)injury in ovariectomized(OVX)rats.Methods A total of 132 female SD rats were subjected,and 48 of them were randomly divided into sham operation group,IR group,OVX group and combined group,with 12 in each group.In order to explore the role of endothelous NOS(eNOS)and inducible NOS(iNOS)in ovariectomization increasing myo-cardial IR injury,another 84 mice were divided into negative sham group,negative IR group,nega-tive combined group,eNOS+IR group,eNOS combined group,iNOS small interfering RNA(si-iNOS)+IR group and si-iNOS combined group,with 12 in each group.The mice of the corre-sponding groups were injected with adeno-associated virus(AAV)overexpressing eNOS or knoc-king down iNOS via tail vein before OVX modeling.Myocardial infarct size,serum levels of lac-tate dehydrogenase(LDH)and creatine phosphokinase isoenzyme(CK-MB),LVEF,LVFS,and expression levels of eNOS and iNOS in the myocardial tissues were measured.Results The com-bined group had significantly increased level of iNOS in myocardium,larger myocardial infarct size and elevated serum LDH and CK-MB levels,but decreased myocardial expression of eNOS and LVEF and LVFS values than the IR group(P＜0.05).When compared with the negative combined group,the myocardial infarct size and serum LDH and CK-MB levels were decreased[(23.51±3.22)％and(26.21±2.93)％vs(58.78±5.42)％,(176.31±15.48 and 169.52±17.12 vs 328.85±37.12 U/L,35.41±6.41 and 34.77±5.94 vs 88.73±9.14 U/L,P＜0.05],and the LVEF and LVFS values were increased[(41.31±3.12)％and(42.09±3.41)％vs(30.77± 2.15)％,(21.47±1.57)％and(21.32±1.42)％vs(15.92±1.33)％,P＜0.05]in the eNOS com-bined group and si-iNOS combined group.Conclusion The decrease of eNOS expression and in-crease of iNOS expression are related to the aggravation of myocardial IR injury in OVX rats.

Objective:To explore the stent apposition and safety of Neuroform EZ and Enterprise 2 stents in treatment of symptomatic intracranial atherosclerotic stenosis (sICAS), and their influencing factors for in-stent restenosis.Methods:A total of 143 sICAS patients treated by Enterprise 2 stents (implanted 143 Enterprise 2 stents, E2 group) and 202 patients treated by Neuroform EZ stents (implanted 202 Neuroform EZ stents, EZ group) were selected from Department of Interventional Radiology, First Affiliated Hospital of Zhengzhou University from January 2017 to January 2022. Stent apposition was evaluated based on reconstructive images of high-resolution flat detector CT. The complications 30 d after surgery and during 6-24 months of follow-up were recorded. Based on DSA or CTA 6 months after surgery, the patency of the two stents was evaluated. Univariate analysis and multivariate Logistic regression analysis were used to determine the independent risk factors for in-stent restenosis.Results:(1) Forty-nine patients had incomplete stent apposition (ISA) after stent release: 24 patients with ISA in E2 group (16.8%, 24/143; 15 of type I and 9 of type II) and 25 with ISA in the EZ group (12.4%, 25/202, 11 of type I and 14 of type II) were found, without statistical difference ( χ 2=1.334, P=0.248); however, ISA incidence in the EZ group (19.0% and 10.3%) was significantly lower than that in the E2 group (41.4% and 25.6%) when the diameter ratio of anterior and posterior vessels of the stenosis lesions≥1.30 or the angle of stent≥75° ( χ 2=4.228, P=0.040; χ 2=4.531, P=0.033). (2) Within 30 d of stenting, 17 patients developed neurological dysfunction-related complications: 8 patients in EZ group and 9 in E2 group were noted, without significant difference ( P=0.324). Clinical follow-up was obtained in 317 patients, and 20 patients developed long-term stroke associated with responsible lesion vessels: 12 patients in EZ group and 8 in E2 group were noted, without significant difference ( P=0.995). (3) Totally, 298 patients received imaging follow-up 6 months after surgery, and 65 patients developed in-stent restenosis: 36 patients in EZ group and 29 in E2 group were noted, without significant difference ( χ 2=0.309, P=0.578). Multivariate Logistic regression analysis showed that diabetes ( OR=2.714, 95% CI: 1.437-5.126, P=0.002), stent apposition ( OR=3.435, 95% CI: 1.223-9.652, P=0.019), lesion stenosis length ( OR=1.176, 95% CI: 1.065-1.300, P=0.001) and immediate postoperative residual stenosis ( OR=1.038, 95% CI: 1.004-1.074, P=0.029) were independent influencing factors for in-stent restenosis. Conclusions:Enterprise 2 and Neuroform EZ stents have high stent apposition and safety in sICAS treatment, but in cases with large diameter ratio of the anterior and posterior vessels of the stenosis lesions (diameter ratio≥1.30) or large angle of the stent (≥75°), Neuroform EZ stent has better stent apposition. Patients with diabetes, ISA, long lesion stenosis or high residual stenosis may trend to have in-stent restenosis.

Objective:To establish the carotid artery in-stent restenosis (ISR) models in Bama pigs after Neuroform EZ stent implantation, and observe and summarize their imaging and pathological characteristics.Methods:Thirteen healthy Bama pigs from Guangxi Province were chosen; carotid artery intima was injuried by balloon over-dilation; Neuroform EZ stents were implanted at the vascular injury sites to establish ISR models. Blood flow at areas accepted carotid artery stent implantation in Bama pigs was monitored by bedside color ultrasound every 2 weeks after surgery; once hemodynamic changes (acceleration or deceleration of the blood flow) in stents were detected, DSA, intravascular ultrasound (IVUS), optical coherence tomography (OCT) and high-resolution MRI (HR-MRI) were performed immediately. Bama pigs were then sacrificed and tissues at the stents were taken; HE staining was used to observe the pathological changes.Results:Thirteen Neuroform EZ stents were implanted into 13 Bama pigs after balloon over-dilation of the unilateral carotid arteries with a technical success rate of 100%. Hemodynamic changes in stents were detected in these 13 pigs (10 with acceleration and 3 with deceleration) at (12.46±3.57) weeks after stenting (ranged from 6-18 weeks); ISR of different degrees was found in all these 13 pigs by DSA with an average stenosis rate of (44.23±9.39)%. IVUS and OCT found that the main body of stents was covered by hyperplastic intima, and thickened intima resulted in local lumen stenosis; and obvious vascular wall enhancement in these lumens was shown on HR-MRI. HE staining showed rupture of intravascular internal elastic lamina and severely arterial intimal hyperplasia;and the hyperplastic intima was mainly composed of smooth muscle cells.Conclusion:Carotid artery ISR models in Bama pigs can be accurately and reliably established at approximately 12 weeks by tearing endovascular intima with balloon over-dilation and implanting Neuroform EZ stents, and multiple imaging and pathology methods confirm that ISR is caused by hyperplastic intima.