Efficacy and Safety of Low-Dose versus High-Dose Postoperative Intrathecal Morphine in 62 Women Undergoing Elective Cesarean Section Delivery at Full Term.

BACKGROUND Adequate pain control is desired in women undergoing cesarean section. This study aimed to compare the efficacy and safety of low- and high-dose postoperative intrathecal morphine in 62 women undergoing elective cesarean section delivery at full term. MATERIAL AND METHODS We performed a prospective, randomized, controlled, multicenter clinical study from April to November 2022. Full-term, 22-38-year-old pregnant women who were singleton pregnancies, weighing 55-80 kg, scheduled for elective cesarean section, were enrolled. A total of 62 patients were randomly assigned into either the low-dose (60 µg morphine, N=32) or high-dose (100 µg morphine, N=30) group. Post-cesarean pain intensity was recorded at 4, 12, and 24 hours. Patients requiring additional rescue analgesics or with adverse effects were documented. RESULTS There were no differences in age, weight, height, gestational age, or operating time between the 2 groups (all P>0.05). The 2 groups also had no statistically significant differences in the resting and exercise pain intensities at 4, 12, and 24 hours after cesarean section (P>0.05). Most patients (53 patients) did not require additional analgesics, suggesting an overall successful analgesic rate of 85.5%. The low-dose group had a lower incidence of pruritus than the high-dose group (13% vs 40%, P=0.029). The 2 groups had no differences in the other adverse effects. CONCLUSIONS A single dose of intrathecal 60 µg morphine could provide adequate analgesia comparable with 100 µg morphine, with a lower incidence of pruritus, in Chinese women after cesarean delivery.

Nano-remediation technologies for the sustainable mitigation of persistent organic pollutants.

The absence of novel and efficient methods for the elimination of persistent organic pollutants (POPs) from the environment is a serious concern in the society. The pollutants release into the atmosphere by means of industrialization and urbanization is a massive global hazard. Although, the eco-toxicity associated with nanotechnology is still being debated, nano-remediation is a potentially developing tool for dealing with contamination of the environment, particularly POPs. Nano-remediation is a novel strategy to the safe and long-term removal of POPs. This detailed review article presents an important perspective on latest innovations and future views of nano-remediation methods used for environmental decontamination, like nano-photocatalysis and nanosensing. Different kinds of nanomaterials including nanoscale zero-valent iron (nZVI), carbon nanotubes (CNTs), magnetic and metallic nanoparticles, silica (SiO2) nanoparticles, graphene oxide, covalent organic frameworks (COFs), and metal organic frameworks (MOFs) have been summarized for the mitigation of POPs. Furthermore, the long-term viability of nano-remediation strategies for dealing with legacy contamination was considered, with a particular emphasis on environmental and health implications. The assessment goes on to discuss the environmental consequences of nanotechnology and offers consensual recommendations on how to employ nanotechnology for a greater present and a more prosperous future.

Optimal Energy Management System of IoT-Enabled Large Building Considering Electric Vehicle Scheduling, Distributed Resources, and Demand Response Schemes.

In the energy system, various sources are used to fulfill the energy demand of large buildings. The energy management of large-scale buildings is very important. The proposed system comprises solar PVs, energy storage systems, and electric vehicles. Demand response (DR) schemes are considered in various studies, but the analysis of the impact of dynamic DR on operational cost has been ignored. So, in this paper, renewable energy resources and storages are integrated considering the demand response strategies such as real-time pricing (RTP), critical peak pricing (CPP), and time of use (ToU). The proposed system is mapped in a linear model and simulated in MATLAB using linear programming (LP). Different case studies are investigated considering the dynamic demand response schemes. Among different schemes, results based on real-time pricing (58% saving) show more saving as compared to the CPP and ToU. The obtained results reduced the operational cost and greenhouse gas (GHG) emissions, which shows the efficacy of the model.

The kite flap for reconstructing tumour excision wounds in the middle and lower face: a retrospective study.

OBJECTIVE: The aim of this study was to present our experience with a kite flap in reconstruction of facial wounds after malignant tumour excision. METHOD: From October 2008 to September 2017, patients with facial malignant tumour were treated in the Xinjiang Uygur Autonomous Region Bazhou People's Hospital with kite flaps after complete excision. The survival rate, colour, cicatrix of the flap and patient satisfaction were recorded after surgery. RESULTS: A total of 95 patients were included in the study. During follow-up, from six months to 8 years, all the kite flaps achieved primary closure and survived well, and the colour and texture were similar to the surrounding skin with no obvious scar. Dysfunction, complications and recurrence had not been reported. CONCLUSION: The kite flap may be a good option in reconstructing facial wounds after malignant tumour excision (diameters 1-5cm). It is a simple surgical method with sufficient blood supply and extensive adaptability. For patients in this study, no obvious scars were formed and the recipient site matched well with the donor site.

[Systematic review and trial sequential analysis of randomized clinical trial of Hongjin Xiaojie Capsules for treatment of hyperplastic disease of breast].

To systemically evaluate the clinical efficacy and safety of Hongjin Xiaojie Capsules for hyperplastic disease of breast(HDBA), so as to provide the evidence for its clinical application. The inclusion criteria are the RCT of single administration of Hongjin Xiaojie Capsules for treatment of HDBA. We retrieved following databases(CNKI, WanFang, VIP, SinoMed, Cochrane Library and PubMed) from their inception to October 1, 2019. Two researchers independently screened out literatures and extracted data, and assessed the methodological quality of eligible RCT according to the criteria in Cochrane Handbook for Systematic Reviews of Interventions. RevMan 5.3 was used for data analysis, binary data was summarized by risk ratio(RR) with confidence intervals(CI) of 95%, and continuous data were summarized by mean difference(MD) with CI of 95%. To estimate the sample size of systematic review, trial sequential analysis(TSA) was performed base on software TSA v0.9 version. Totally 14 RCTs were included, involving 3 057 patients. The results of Meta-analysis showed a significantly higher cure rate(RR=1.13, 95%CI[1.03, 1.25], P=0.01) and higher total effective rate(RR=1.09, 95%CI[1.05, 1.13], P<0.000 1) in Hongjin Xiaojie Capsules group than those in the Juyuansuan Tamoxifen group. The incidence of adverse events was significantly higher in Juyuansuan Tamoxifen group than that in Hongjin Xiaojie Capsules group(RR=0.28 95%CI[0.16, 0.49], P<0.001), and the adverse events included nausea, vomiting, abdominal pain, diarrhea, irregular menstruation, amenorrhea, unclear vision, dizziness and headache. The TSA for the cure rate demonstrated that the current available data reached the expected value. However, due to the low effect intensity of evidence, the pooled results might be affected by high risk bias of trials. The quality of evidence of included trials was generally low or very low. Inverted funnel diagram showed possible publication bias. This review suggested that Hongjin Xiaojie Capsules were potentially effective and safe in treatment of HDBA, especially, the incidences of drug-related adverse events from Hongjin Xiaojie Capsules were significantly lower than those from tamoxifen. However, because of lack of high-quality evidence for drawing a conclusion, more rigorously designed and high-quality trials are needed to confirm the efficacy and safety of Hongjin Xiaojie Capsules.

High-accuracy transient response fiber optic seismic accelerometer using a shock-absorbing ring as a mechanical antiresonator.

This study proposes a high-accuracy transient response fiber optic seismic accelerometer based on the resonance suppression mechanism. A shock-absorbing ring is embedded in the accelerometer structure, which acts as a mechanical antiresonator. The experimental results show that the sensitivity at the resonance frequency is suppressed by 21.79 dB, and the 3 dB operating bandwidth is extended without reducing the average sensitivity. Under this condition, the high-accuracy transient response is obtained during the vibration-event test. This study provides a practical seismic acquisition technique solution for vertical seismic profiling monitoring in the smart oilfield.

Self-suppression of common-mode noises of the different fiber optic interferometric accelerometers.

This study proposes two new fiber optic interferometric accelerometers with the utilization of the push-pull structure, one is based on the principle of triple low-reflectivity fiber Bragg gratings, and the other is based on the 1x3 unbalanced Michelson interferometer. The proposed accelerometers are capable of suppressing the common-mode noises (CMNs) by themselves without additional reference accelerometers, and therefore reducing the volume and the cost of the sensing system. Besides, the accelerometers can also suppress the sensor noises caused by the environment, and therefore show better CMNs suppression effect than the traditional method of using the reference accelerometer. The two accelerometers are experimentally verified and show respectively an improvement of 33 dB and 28 dB in CMNs suppression at 100 Hz. Both presented fiber optic accelerometers show huge advantages for the large-scale quasi-distributed oil and gas reservoir monitoring applications.

Association between serum gamma-glutamyl transferase and serum uric acid levels in Chinese females: A cross-sectional study.

OBJECTIVE: To investigate the association between serum gamma-glutamyl transferase (GGT) levels and serum uric acid levels in middle-aged and elderly Chinese females. METHODS: A cross-sectional population survey was performed in Luzhou, China (2014). Questionnaires, physical examinations and biochemical tests were conducted. Finally, we included 2486 females who were > 40 years old as participants. Multiple linear regression analysis was used to estimate the association of serum acid levels and other variables. Serum GGT levels were divided into four groups using the 25th, 50th and 75th percentiles as cut-off points. Finally, binary logistic regression analysis was used to investigate the association of different serum GGT quartiles with the risk of hyperuricemia. RESULTS: The prevalence of hyperuricemia was 25.1% in the studied population and gradually increased across the serum GGT quartiles (P < 0.05). Binary logistic regression analysis showed that compared with subjects in the lowest quartile of serum GGT levels, the adjusted odds ratio (ORs) for uric acid in the highest quartile was 2.34 (95% confidence interval (CI), 1.68-3.28, P < 0.001),after corrections for TG, TC, HDL-C, LDL-C, creatinine (CR), GGT, AST, ALT, fasting plasma glucose (FPG), postprandial 2-h plasma glucose, hemoglobin A1c(HbA1c), age, BMI, SBP, DBP, waist-to-hip ratio and neck circumference (NC). CONCLUSIONS: The serum GGT level is associated with hyperuricemia in middle-aged and elderly Chinese females.

Real emotional experience of family members of patients transported within hospital in neurosurgical intensive care unit: A descriptive qualitative study.

AIM: To understand the real experience of family members of patients in neurosurgical intensive care unit (NICU) during intra-hospital transport (IHT), explore their inner needs and provide effective intervention measures for the construction of standardized IHT plan. DESIGN: A descriptive qualitative study. METHODS: For the purposes of this study, 10 family members of IHT patients were included using a purposive sampling method. Semi-structured in-depth interviews were used to collect the data, Nvivo 11 software was used to organize the data, and Colaizzi's 7-step descriptive phenomenology method was used to analyse the data. RESULTS: A total of three themes and nine subthemes were extracted, namely: Experience of emotional changes at different stages (uncertainty before transfer, complex internal activity during transit, ambivalence after transfer); Perception of problems in IHT (poor doctor-patient communication, weak awareness of risk assessment, deficiencies in the transfer procedure); Consciousness of the real needs (emotional respect and closeness, stay informed of the progression of the disease, greater social support). CONCLUSION: Family members of patients in the NICU have complex internal experiences and multiple support needs during IHT, reflecting the need for further standardization of the transport process. In the future, we should improve the mode of safe IHT involving doctors, nurses and family members of patients, ensure the safety of patient transport, meet the social support needs of family members and improve the experience of IHT and the medical satisfaction of family members.

ERS Mediated by GRP-78/PERK/CHOP Signaling Is Involved in Fluoride-Induced Ameloblast Apoptosis.

Fluoride can be widely ingested from the environment, and its excessive intake could result in adverse effects. Dental fluorosis is an early sign of fluoride toxicity which can cause esthetic and functional problems. Though apoptosis in ameloblasts is one of the potential mechanisms, the specific signal cascade is in-conclusive. High-throughput sequencing and molecular biological techniques were used in this study to explore the underlying pathogenesis of dental fluorosis, for its prevention and treatment. A fluorosis cell model was established. Viability and apoptosis rate of mouse ameloblast-derived cell line (LS8 cells) was measured using cell counting kit-8 (CCK-8) assay and flow cytometry analysis. Cells were harvested with or without 2-mM sodium fluoride (NaF) stimulation for high-throughput sequencing. Based on the sequencing data, subcellular structures, endoplasmic reticulum stress (ERS), and apoptosis related biomarkers were verified using transmission electron microscopy, quantitative real-time polymerase chain reaction, and Western blotting techniques. Expression of ERS markers, apoptosis related proteins, and enamel formation enzymes were detected using Western blotting after addition of 4-phenylbutyrate (4-PBA). NaF-inhibited LS8 cells displayed time- and dose- dependent viability. Additionally, apoptosis and morphological changes were observed. RNA-sequencing data showed that protein processing in endoplasmic reticulum was obviously affected. ERS and apoptosis were induced by excessive NaF. Downregulation of kallikrein-related peptidase 4 (KLK4) was also observed. Inhibition of ERS by 4-PBA rescued the apoptotic and functional protein changes in cells. Excessive fluoride induces apoptosis by activating ERS, which is mediated by GRP-78/PERK/CHOP signaling. Key proteinase is present in maturation-stage enamel; KLK4 was also affected by fluoride, but rescued by 4-PBA. This study presents a possibility for therapeutic strategies for dental fluorosis, while further exploration is required.

GIS-based assessment of spatial and temporal disparities of urban health index in Shenzhen, China.

Purpose: To explore the inter-regional health index at the city level to contribute to the reduction of health inequalities. Methods: Employed the health determinant model to select indicators for the urban health index of Shenzhen City. Utilized principal component analysis, the weights of these indicators are determined to construct the said health index. Subsequently, the global Moran's index and local Moran's index are utilized to investigate the geographical spatial distribution of the urban health index across various administrative districts within Shenzhen. Results: The level of urban health index in Shenzhen exhibits spatial clustering and demonstrates a positive spatial correlation (2017, Moran's I = 0.237; 2019, Moran's I = 0.226; 2021, Moran's I = 0.217). However, it is noted that this clustering displays a relatively low probability (90% confidence interval). Over the period from 2017 to 2019, this spatial clustering gradually diminishes, suggesting a narrowing of health inequality within economically developed urban areas. Conclusion: Our study reveals the urban health index in a relatively high-income (Shenzhen) in a developing country. Certain spatially correlated areas in Shenzhen present opportunities for the government to address health disparities through regional connectivity.

Purification and antioxidant activities of baicalin isolated from the root of huangqin (Scutellaria baicalensis gcorsi).

Baicalin is a flavonoid from the root of huangqin (Scutellaria baicalensis gcorsi, a kind of Traditional Chinese Medicine and food condiment) with two pro phenolic hydroxyls. In this manuscript, high purity of baicalin (95.5 %) was isolated from the root of huangqin and its antioxidant activities were investigated. The antioxidant properties of baicalin were evaluated by scavenging of the diphenylpicrylhydrazyl radical (DPPH), reducing power, and iron-chelating assays, compared to ascorbic acid and BHT. The results of antioxidant activity showed that the activities of baicalin were significantly better than these of ascorbic acid and BHT, and the linear correlations were good in these three assays.

Right ventricular and left atrial and left ventricular myxomas: report of a case.

Myxomas are common cardiac tumors, which are usually managed by complete excision. We report a case of myxomas at different stages of development found simultaneously in the left atrium and both ventricles. The patient underwent successful surgical excision of all myxomas and there has been no clinical or echocardiographic evidence of recurrence or valvular insufficiency in 6 months of follow-up.

Protocadherin alpha 3 inhibits lung squamous cell carcinoma metastasis and epithelial-mesenchymal transition.

BACKGROUND: Lung squamous cell carcinoma (LUSC) is associated with poor clinical prognosis and lacks available targeted therapy. Given that the major threat of cancer is metastasis, delineation of the molecular mechanism underlying it would help devise therapeutic strategies. OBJECTIVE: To investigate the functional role of protocadherin alpha 3 (PCDHA3) in LUSC, as well as investigate the underlying molecular mechanism. METHODS: Data for PCDHA3 expression and clinical information in The Cancer Genome Atlas (TCGA) were extracted and analyzed in the UALCAN platform. Expression levels of PCDHA3 in LUSC cell lines were analyzed via RT-PCR and western blot. Overexpression of PCDHA3 was conducted via plasmid transfection. CCK-8 and cell cycle assays were utilized to investigate effect of PCDHA3 on cell proliferation. Transwell assay was used to detect migration and invasion. The underlying mechanism was demonstrated via western blot analysis. RESULTS: Our data indicate that PCDHA3 was low expressed in three kinds of LUSC cell lines and best in H520 cells. Furthermore, overexpression of PCDHA3 could significantly impair LUSC cells proliferation, invasion and migration. Moreover, PCHDA3 repressed the biomarkers of mesenchymal (N-cadherin, fibronectin and vimentin) and increased expression of epithelial markers (E-cadherin and α-catenin). On the other hand, PCDHA3 overexpression partially blocked epithelial-mesenchymal transition. CONCLUSIONS: PCDHA3 suppressed the LUSC cells proliferation, invasion and migration via inhibiting the expression of EMT signatures, suggesting that PCDHA3 could serve as a valuable therapeutic target for LUSC therapy.

[µ-1,4-Bis(1,2,4-triazol-1-ylmeth-yl)benzene]-bis-[aqua-(pyridine-2,6-dicarboxyl-ato)copper(II)] monohydrate.

The title compound, [Cu(2)(C(7)H(3)NO(4))(2)(C(12)H(12)N(6))(H(2)O)(2)]·H(2)O, displays a discrete dinuclear structure, in which the central Cu(II) atom is five-coordinated in a distorted square-based pyramidal coordination geometry and the flexible ligand 1,4-bis-(1,2,4-triazol-1-ylmeth-yl)benzene adopts a bis-monodentate bridging mode linking the Cu(II) atoms. It is further assembled by O-H⋯O hydrogen-bond inter-actions involving both the coordinated and uncoordinated water molecules. The latter exhibits half-occupancy.

In vitro study in the endothelial cell compatibility and endothelialization of genipin-crosslinked biological tissues for tissue-engineered vascular scaffolds.

To overcome the cytotoxicity of the chemical reagents used to fix bioprostheses, genipin, a naturally occurring crosslinking agent, was used to fix biological tissues in present study. We prepared the biological vascular scaffolds through cell extraction and fixing the porcine thoracic arteries with 1% (by w/v) genipin solution for 3 days, and then examined their mechanical properties and microstructures; glutaraldehyde- and epoxy-fixed counterparts were used as controls. HUVECs were seeded on the type I collagen-coated surface of different modified acellular vascular tissues (fixed with different crosslinking agents), and the growths of HUVECs on the specimens were demonstrated by means of MTT test, the secretion of PGI2 and vWF by HUVECs on the various specimens was also measured. Finally, HUVECs were seeded on the luminal surface of acellular biological vascular scaffolds (<6 mm internal diameter) which were, respectively, treated in the same manner described above, and then cultured for 9 days. On the ninth day, the HUVECs on the luminal surface of these vascular scaffolds were examined morphologically and by immunohistochemistry. Genipin-fixation can markedly diminish antigenicity of the vascular tissues through partially getting rid of cell or reducing the level of free amino groups in the vascular tissues. Genipin-fixed acellular vascular tissues mimicked the natural vessels due to the maintenance of the integrity of total structure and the large preservation of the microstructures of collagen fibers and elastic fibers; therefore, it appeared suitable to fabricate vascular scaffolds in mechanical properties. Compared to controls, the genipin-fixed acellular vascular tissues were characterized by low cytotoxicity and good cytocompatibility. The HUVECs can not only proliferate well on the genipin-fixed acellular vascular tissues, but also preserve the activities and function of endothelial cells, and easily make it endothelialized in vitro. The results showed that the genipin-fixed acellular porcine vascular scaffolds should be promising materials for fabricating vascular grafts or the scaffolds of tissue-engineered blood vessels.

Blepharoptosis correction by excision of levator muscle and tarsus in Asians.

To establish a technique for moderate and severe blepharoptosis to exert the function of residual levator muscle, 30 patients (38 eyes) who had moderate and severe blepharoptosis were treated, and the results including complications were followed up and valued. Operation was performed via anterior transcutaneous incision. After separating levator muscle and tarsus, the amount excision of levator muscle and tarsus was accurately estimated. Part of levator muscle associated with tarsus was excised. The position and contour of the upper lid margin, uncovering of the pupils, and symmetry of the palpebral fissures were assessed. Incidence of postoperative complications, including infection, was also considered. Among the 38 eyes, all had a good or fair outcome except for 2 eyes. Eyelid was raised to normal level by this technique with a natural eyelid contour. Some cases presented slight neuropathies in the early stage after operation. We concluded that excision of levator muscle and tarsus could be applied to correct moderate and severe blepharoptosis with some residual levator function, which could achieve good aesthetic results ultimately.

Use of Transthoracic Transdiaphragmatic Approach Assisted with Radiofrequency Ablation for Thoracoscopic Hepatectomy of Hepatic Tumor Located in Segment VIII.

BACKGROUND: Resection of segment VIII remains challenging despite the widespread laparoscopic hepatectomies in past decades,1,2 especially for patients with cirrhosis. In this case, we combined radiofrequency ablation (RFA) with transthoracic approach, which was a novel approach for laparoscopic-guided hepatectomy of segment VIII in a cirrhotic patient. PATIENT: A 42-year-old male patient with a body mass index of 22.0 kg/m2 suffered from HBV-related cirrhosis was admitted to our institution. The preoperative MRI showed a 1.3 cm liver mass located in segment VIII. The preoperative AFP is 192 ng/ml. The patient was considered to have hepatectomy using transthoracic transdiaphragmatic approach with the assist of RFA. TECHNIQUE: The patient was placed in a left lateral position with artificial pneumothorax in the right lung and left side ventilation. Three trocars were placed into the right thoracic space. Transdiaphragmatic intraoperative ultrasonography (IOUS) was performed to confirm the size and location of the lesion. In order to decrease the blood loss during parenchymal dissection and to reach tumor-free margins, the RFA was performed around the tumor before hepatectomy. After that the resection was carried out along the ablative margin. After the specimen was removed, the diaphragm was sutured and a closed thoracic drainage tube was placed. The operative time was 210 min with an estimated blood loss of 50 mL. The postoperative course was uneventful. Antibiotics was used in the first 24 h post-operation to prevent thoracic infection. Drainage tube was pulled out on the fourth day post-operation when we observed the daily fluid volume was less than 100 ml for 2 days and X-ray showed no gases and effusion in chest cavity. The pathology confirmed the diagnosis of hepatocellular carcinoma and the surgical margin was negative. The patient was discharged on the 8th day after surgery. DISCUSSION: Lesions in the postero-superior segments still be challenging as we know.3 Previous studies showed that the procedure's results, such as the blood loss and operative time, were similar between thoracoscopic hepatectomy and laparoscopic hepatectomy, even the former was better.2,4 Thus, for the superficial lesions in the postero-superior segments, and not more than 3 cm in diameter, thoracoscopic hepatectomy is recommended. Furthermore, a patient with a hostile abdomen who has a lesion in S7 or S8, transthoracic approach may be particularly helpful. However, functional lung is required due to the unilateral ventilation. Besides, anatomic resections are difficult to perform from the top.5 In this case, we used RFA before liver resection, and the tumor cells were destroyed to ensure the negative margin of the cut, and the bleeding blood vessels were also closed. This method can make a significant reduction of blood loss in the patients with cirrhosis compared with conventional hepatectomy (whether through thoracoscopic6 or laparoscopic7 approach). CONCLUSION: The novel approach for transthoracic hepatectomy was safe and feasible for lesions of segment VIII in selected patients with cirrhosis,8 which was associated with reduced blood loss and a safe surgical margin.

The role of the precuneus and posterior cingulate cortex in the neural routes to action.

Neural substrates of action to the object or this specific direct route, however, remain unclear, especially for the connection from the visual pathway to the motor cortex. The study examined this issue by conducting an fMRI experiment, in which two action generation tasks involving pictures of real objects (PA) and the object's nouns (NA) were used, with pictures naming (PN) and covert noun reading (NR) being the control tasks. The result showed that the model predefined for the PCC and precuneus connecting IPL to the posterior-medial frontal cortex dominated over the others (with 0.45 probability), suggesting that the PCC and the precuneus locate at the neural substrates of action to the object. Furthermore, a feasibility study suggests that the neural pathway composed of the V3/MT, precuneus, PCC, and PM (premotor cortex) forms the direct route from perception to action, which also links to the dorsal pathway so that the perception of objects bypasses the semantic ventral pathway and then directly cues actions via the affordance.

[Minimal invasive microscopic tooth preparation based on endodontic, periodontal and functional health].

Tooth preparation is the primary and core operation technique for dental esthetic restoration treatment, due to its effect of providing restoration space, bonding interfaces and marginal lines for dental rehabilitation after tooth tissue reduction. The concept of microscopic minimal invasive dentistry put forward the issue of conducting high-quality tooth preparation, conserve tooth-structure, protect vital pulp and periodontal tissue simultaneously. This study reviewed the concepts, physiology background, design and minimal invasive microscopic tooth preparation, and in the meantime, individualized strategies and the two core elements of tooth preparation (quantity and shape) are listed.