Nevin Manimala

Zhonghua Kou Qiang Yi Xue Za Zhi. 2021 Dec 9;56(12):1224-1229. doi: 10.3760/cma.j.cn112144-20210927-00442.

ABSTRACT

Objective: To investigate the clinical effect and satisfaction of partially edentulous patients restored with posterior implant-supported single crown by digital impression technique and traditional silicon rubber impression, in order to provide clinical reference. Methods: Sixty-four partially edentulous patients who visited the Department of Prosthodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University between March 2018 and January 2021 were enrolled. There were 31 male and 33 female, and the age of the group of patients was (49.3±13.3) years. The 113 implants placed in this group of patients were divided into digital impression group (n=70) and silicone rubber impression group (n=43) according to different impression techniques, and were restored with screw-retained full zirconia single crown, and the patients were followed up for 3-36 months after treatment. The implant survival rate, upper prosthesis, peri-implant soft tissue status, marginal bone loss and patients satisfaction were recorded to evaluate the clinical effects of two impression techniques in posterior implant-supported single crown. Results: In sixty-four patients, digital impression accounted for 62% (40/64), and silicon rubber impression accounted for 38% (24/64), the survival rate of 113 implants was 100% (113/113). The prevalence of interproximal contact loss, food impaction and mechanical complication of the upper full zirconia single crown restorations were 22.7% (41/181), 8.0% (9/113) and 2.7% (3/113) separately. All the mechanical complications were abutment screw loosening. All patients maintained good oral hygiene status, the incidences of peri-implantitis and peri-implant mucositis were 0.9% (1/113) and 4.4% (5/113) respectively. The marginal bone loss was (0.24±0.11) mm. The median of satisfaction visual analogue scale score in patients was 9-10, but no statistically significant differences of all the above results were observed between the two impression techniques (P>0.05). Conclusions: The clinical effect of partially edentulous patients restored with posterior implant-supported single crown using two different impression techniques is good and the satisfaction of patients is high, but the long-term clinical effect remains to be further observed.

PMID:34915657 | DOI:10.3760/cma.j.cn112144-20210927-00442

Zhonghua Kou Qiang Yi Xue Za Zhi. 2021 Dec 9;56(12):1211-1216. doi: 10.3760/cma.j.cn112144-20211007-00456.

ABSTRACT

Objective: To investigate the effect of guided bone regeneration (GBR) on marginal bone loss (MBL) in the region of the mandibular posterior tooth by using a retrospective cohort study, in order to provide reference for clinical practice. Methods: The research subjects were patients who received dental implants from October 2008 to June 2011 in the region of the mandibular posterior tooth at the Department of Oral Implantology, School of Stomatology, The Fourth Military Medical University. According to whether GBR was performed or not and the time of implant insertion, the patients were divided into the controls group (patients without bone grafting), simultaneous GBR implantation group, and delayed GBR implantation group. On this basis, the MBL was measured according to radiographs by comparing the marginal bone level from that of immediate postoperation 10 years ago. General data was collected and compared among groups, including modified plaque index (mPI), modified sulcus bleeding index (mSBI), probing depth (PD), and gingival papilla height. Results: The controls group (patients without bone grafting), implantation group, and delayed GBR implantation group followed 58, 76, 26 implants in 26, 32, 13 patients aging at (46.5±9.9), (45.5±10.7), (58.3±6.4) respectively. The duration of the follow-up was (11.2±0.7), (11.1±0.8), (11.1±0.9) years respectively. The 10-year implant survival rate was 100% (58/58), 100% (76/76), 100% (26/26). The MBL was (0.91±0.28), (0.84±0.27), (1.01±0.27) mm respectively. The MBL difference of patients with simultaneous GBR implantation and delayed GBR implantation showed statistical significance (P<0.05), but these two groups showed no statistical significance compared with the controls group (P>0.05). The mPI, mSBI, PD, and gingival papilla height of the three groups all had no significance on statistics (P>0.05). Conclusions: It can be concluded that there is no difference in long-term marginal bone resorption between simultaneous and delayed implantation with or without GBR (using autologous blood mixed with granular bone meal) in the posterior mandibular area.

PMID:34915655 | DOI:10.3760/cma.j.cn112144-20211007-00456

Zhonghua Kou Qiang Yi Xue Za Zhi. 2021 Dec 9;56(12):1197-1204. doi: 10.3760/cma.j.cn112144-20210918-00419.

ABSTRACT

Objective: To investigate the influence of different characteristics of implant-supported fixed dental prostheses on the incidence of peri-implant disease. Methods: Prospective cohort was established for patients who received implant-supported fixed dental prostheses at the Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University between June 2014 and September 2015. Several patient-related factors, implant prostheses factors, and oral hygiene maintenance factors were collected. The Log-rank test was used to compare the peri-implant disease rates of various factors, and the Cox proportional hazards model was used to conduct multivariate study on single factor significant factors to analyze the impact on the incidence of peri-implant disease. Results: A total of 214 subjects and 351 implants were included in the cohort, the follow-up period was (11.0±3.5) months. Finally, 43.0% (92/214) of patients and 37.3% (131/351) of implants developed peri-implant diseases. The incidence of peri-implant mucositis and peri-implantitis was 41.1% (88/214) and 4.2% (9/214) at the subject level,and 34.2% (120/351) and 3.1% (11/351) at the implant level. Among the factors associated with the implant prosthesis, single factor Log-rank analysis showed that prostheses retention methods, proximal contact of the prostheses, occlusion situation were statistical significance (P<0.05). Multivariate analysis using Cox proportional hazards model showed that screw retention (hazard ratio=2.38, 95%CI: 1.42-3.99), proximal contact loss of the prostheses (hazard ratio=2.36, 95%CI: 1.31-4.27) were independent risk factors for peri-implant disease (P<0.05). Conclusions: Factors such as prostheses retention mode and proximal contact characteristics have important influence on the health status of the implant.

PMID:34915653 | DOI:10.3760/cma.j.cn112144-20210918-00419

Zhonghua Zhong Liu Za Zhi. 2021 Dec 23;43(12):1292-1297. doi: 10.3760/cma.j.cn112152-20200916-00828.

ABSTRACT

Objective: To investigate whether cachexia affects the treatment effect of immune checkpoint inhibitors for non-small cell lung cancer (NSCLC). Methods: The prognosis of 62 patients with advanced NSCLC who received anti-programmed cell death-1 (PD-1) in Henan Provincial People’s Hospital from 2019 to 2021 were retrospectively analyzed. The cachexia was evaluated before and after the second course of immunotherapy. Kaplan-Meier and Log rank methods were used for survival analysis, Cox regression model was used for multivariate analysis, and Spearman’s correlation analysis was used for correlation analysis. Results: After the second course of immunotherapy, psoas major muscle area (PMMA) values of the cachexia group and the control group were (14.10±4.09) and (11.66±3.22) cm(2) respectively, with statistics significance (P=0.001). The level of Prealbumin and body weight were correlated with cachexia (P<0.05). The 6-month and 1-year survival rates of 62 cases in the whole group were 58.6% and 42.5%, respectively. The progression-free survival (PFS) in the control group (7.6 months) was higher than that in the cachexia group (3.8 months, P=0.006). The PFS in patients with high expression of PD-L1 (7.1 months) was longer than that of patients with low expression (3.8 months, P=0.009). The overall survival (OS) in the cachexia group (6.3 months) was lower than that in the control group (18.2 months, P=0.006). The OS in patients with high expression of PD-L1 (14.5 months) was longer than that of patients with low expression (1 months, P=0.038). The level of Prealbumin, the level of PD-L1 expression and the change rate of PMMA were related to the OS of the patients (P<0.05). The level of Prealbumin and the change rate of PMMA were the independent influencing factors of the OS (P<0.05). The PMMA and the level of Prealbumin were negatively correlated (r=-0.003 8, P<0.05). Conclusion: Cachexia has a negative impact on the outcomes of patients who received anti-PD-1 immune checkpoint inhibitor therapy.

PMID:34915639 | DOI:10.3760/cma.j.cn112152-20200916-00828

Zhonghua Zhong Liu Za Zhi. 2021 Dec 23;43(12):1287-1291. doi: 10.3760/cma.j.cn112152-20210621-00461.

ABSTRACT

Objective: To explore and describe clinicopathological characteristics and prognosis of patients with double primary breast cancer (BC) and thyroid cancer (TC). Methods: Medical records of 98 patients diagnosed with double primary breast and thyroid cancer in National Cancer Center (NCC)/Cancer Hospital between January 1, 2001 and December 31, 2020 were retrospectively collected. All of the patients were followed up until January 1, 2021 to acquire survival data. Univariate survival analysis was conducted by Kaplan-Meier method, and multivariate survival analysis was carried out using the Cox proportional hazard model. Results: All of 98 patients in the group were women. The age at diagnosis of the first tumor ranged from 26-72 years old, and the median age was 47 years old. The BC recurring TC (breast methyl) group included 18 cases, TC recurring BC (methyl breast) group included 60 cases, BC and TC simultaneously occurred group (the two are diagnosed within 3 months) included 20 cases. There were statistically significant differences in breast cancer pathological grading, breast cancer postoperative radiotherapy, and combined with other tumors in breast methyl group, methyl breast group and the simultaneous group (P<0.05). Among the 98 patients, 14 had recurrence and metastasis, and 7 died. The patients who died from tumors were all those with TC recurrence of BC. There were no statistically significant differences in the death, recurrence and metastasis of patients in the breast methyl group, methyl breast group and the simultaneous group (P>0.05). Univariate analysis showed that BC stage and estrogen receptor (ER) were related to overall survival (P<0.05), while the family history of BC, BC stage, and ER were not related with the recurrence and metastasis (P<0.05). Multivariate analysis showed that BC family history, ER positive, and the order of tumor diagnosis (TC recurring BC) were independent influencing factors for the recurrence and metastasis (P<0.05). Conclusion: ER negative is a poor prognostic factor for the double primary breast and thyroid cancer.

PMID:34915638 | DOI:10.3760/cma.j.cn112152-20210621-00461

Zhonghua Zhong Liu Za Zhi. 2021 Dec 23;43(12):1264-1268. doi: 10.3760/cma.j.cn112152-20190923-00618.

ABSTRACT

Objective: To investigate the effect of apoptosis-associated protein kinase-like 1 (DAPL1) hypomethylation on prognosis of lung cancer patients with epidermal growth factor receptor gene exon 19 deletion (EGFR Del19) mutation. Methods: The clinicopathological data of lung cancer patients in databases of genomic data sharing (GDC) TCGA lung adenocarcinoma, TCGA lung adenocarcinoma, and TCGA lung cancer were collected to analyze the effect of DAPL1 methylation level on the prognosis of patients with EGFR Del19 mutation. Linear regression model was used for correlation analysis, Kaplan-Meier method was used to draw the survival curve, and the difference of survival curve between the two groups was tested by Log rank. Results: In GDC TCGA lung adenocarcinoma, TCGA lung adenocarcinoma and TCGA lung cancer databases, the 5-year survival rates of lung cancer patients with high DAPL1 expression (31.9%, 27.5% and 33.0%, respectively) were higher than those with low DAPL1 expression (11.0%, 11.6% and 13.8%, respectively). The differences were statistically significant (P=0.006, 0.028 and 0.025, respectively). The median expression levels of DAPL1 in patients with EGFR Del19 mutation (12.8, 2.75 and 2.9, respectively) were higher than those in patients with other EGFR mutations (11.6, 1.75 and 1.8, respectively, P<0.05). In TCGA lung adenocarcinoma and TCGA lung cancer database, the 5-year survival rate of lung cancer patients with lower DAPL1 methylation levels (22.4% and 16.4%, respectively) were higher than those of lung cancer patients with higher DAPL1 methylation levels (15.1% and 14.2%, respectively), with statistical significance (P<0.05). The expression level of DAPL1 was positively correlated with the EGFR mutant subtype (r=0.909, P<0.05), and negatively correlated with DNA methylation (r=-0.891, P<0.05). The expression of DAPL1 in lung cancer patients was regulated by DNA methylation, which affected the prognosis of lung cancer patients. Conclusion: High DAPL1 expression, or hypomethylation, is associated with lung cancer EGFR Del19 mutation subtype, and DAPL1 hypomethylated lung cancer patients have longer overall survival.

PMID:34915634 | DOI:10.3760/cma.j.cn112152-20190923-00618

Zhonghua Zhong Liu Za Zhi. 2021 Dec 23;43(12):1255-1263. doi: 10.3760/cma.j.cn112152-20210729-00558.

ABSTRACT

Objective: To explore the relationship between expression levels of CLOCK mRNA and protein and the clinical characteristics of patients with nasopharyngeal carcinoma. Methods: The frozen tissue specimens from 33 patients with nasopharyngeal carcinoma in the Affiliated Tumor Hospital of Guizhou Medical University from 2018 to 2019 were collected. Seventeen cases of tissue specimens from patients with nasopharyngeal chronic inflammation in the Affiliated Hospital of Guizhou Medical University in 2019 were collected. From 2008 to 2014, 68 cases of formalin-fixed paraffin-embedding (FFPE) nasopharyngeal carcinoma tissue and 37 cases of FFPE nasopharyngeal chronic inflammation tissue were collected from the Affiliated Tumor Hospital of Guizhou Medical University. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot (WB) were used to detect the mRNA and protein expression levels of CLOCK. The nasopharyngeal carcinoma cells including CNE1, CNE2, 5-8F and the normal nasopharyngeal epithelial cell NP69 were cultured. qRT-PCR was used to detect the expression level of CLOCK mRNA in each cell line at the time points of ZT2, ZT6, ZT10, ZT14, ZT18 and ZT22. The cosine method was used to fit the rhythm of CLOCK gene in nasopharyngeal carcinoma. The protein expression of CLOCK protein was detected by using immunohistochemical method in 68 cases of nasopharyngeal carcinoma and 37 cases of nasopharyngeal chronic inflammation tissue. Survival was analyzed by Kaplan-Meier method and Log rank test, and the influencing factors was analyzed by Cox regression model. Results: The expression levels of CLOCK mRNA in CNE1, CNE2 and 5-8F cells (0.63±0.07, 0.91±0.02 and 0.33±0.04, respectively) were lower than that in NP69 cell (1.00±0.00, P<0.05). The expression levels of CLOCK protein in CNE1, CNE2 and 5-8F cells (0.79±0.06, 0.57±0.05 and 0.74±0.10, respectively) were lower than that of NP69 cells (1.00±0.00, P<0.05). The expressions of CLOCK mRNA in nasopharyngeal carcinoma cells including CEN1, CNE2, 5-8F and normal nasopharyngeal epithelial cell NP69 were different at different time points, with temporal fluctuations. The fluctuation periods of CLOCK mRNA in CNE1, CNE2, 5-8F, and NP69 cells were 16, 14, 22 and 24 hours, respectively. The peak and trough times were ZT10: 40 and ZT18: 40, ZT10 and ZT3, ZT14: 30 and ZT3: 30, ZT12: 39 and ZT0: 39, respectively. CLOCK mRNA and protein expression levels in nasopharyngeal carcinoma tissues (0.37±0.20 and 0.20±0.26, respectively) were lower than those in nasopharyngeal chronic inflammation tissues (1.00±0.00 and 0.51±0.41, respectively, P<0.05). The 1, 3, and 5-year survival rates of patients in the CLOCK protein high expression group (CLOCK protein expression level ≥ 0.178) were 96.2%, 92.1%, and 80.1%, respectively, which were higher than those in the low expression group (CLOCK protein expression level <0.178, 92.9% , 78.6% and 57.1%, respectively, P=0.009). The 1, 3, and 5-year progression-free survival (PFS) rates of patients in the CLOCK protein high expression group were 96.2%, 87.8%, and 87.7%, respectively, which were higher than those in the low expression group (92.7%, 82.2%, and 70.8%, respectively, P=0.105). Compared with the low-expression group (100.0%, 96.9%, and 90.0%, respectively), the 1, 3, and 5-year recurrence-free survival rates of patients in the CLOCK protein high expression group (100.0%, 95.7%, and 95.7%, respectively) were not statistically significant (P=0.514). Compared with the low-expression group (92.7%, 82.2%, and 79.3%), the 1, 3, and 5-year survival rates without metastasis in the CLOCK protein high expression group (96.2%, 92.0%, and 92.0%, respectively) were not statistically significant (P=0.136). CLOCK protein expression and T stage were independent prognostic factors of overall survival (P<0.05). Conclusions: The expression of CLCOK is downregulated in the nasopharyngeal carcinoma cell and nasopharyngeal carcinoma tissues. Clock gene CLOCK is rhythmically expressed in the nasopharyngeal carcinoma cells and normal nasopharyngeal epithelial cells. Compared with normal nasopharyngeal epithelial cells, the fluctuation period of CLOCK in nasopharyngeal carcinoma cells is shortened. The overall survival of patients in the CLOCK protein high expression group is better than that of low expression group. The expression of CLOCK protein is an independent influencing factor for overall survival. CLOCK gene may be a potential tumor suppressor gene in the nasopharyngeal carcinoma.

PMID:34915633 | DOI:10.3760/cma.j.cn112152-20210729-00558

Zhonghua Zhong Liu Za Zhi. 2021 Dec 23;43(12):1248-1254. doi: 10.3760/cma.j.cn112152-20190916-00598.

ABSTRACT

Objective: To establish a cytokine release syndrome (CRS) mouse model related to CAR-T cell therapy and provide a research model for the clinical phenomena. Methods: CAR-T cells targeting human CD19 molecule were constructed by molecular cloning and lentiviral transfection. Flow cytometry (FACS) was used to detect the transfection efficiency of CAR-T cells. The tumor-killing efficiency of CAR-T cells was detected by ELISA and flow cytometry. The CAR-T cells were injected into the tumor-bearing SCID/Beige mice through tail vein, and divided into phosphate buffered solution (PBS) group, low-burden group (1×10(5) Raji-Luc2 cells) and high-burden group (5×10(5) Raji-Luc2 cells). The tumor treatment effect was detected by animal in vivo imaging. Serum levels of cytokines including human IFN-γ, human IL-2, mouse IL-6, and mouse GM-CSF were measured by ELISA. The health status of the mice was evaluated by pathological examination. Results: The health scores of T cell group and T cell+ OKT-3 group were (1.15±0.08) and (2.90±0.15), respectively, after the injection of human T cell and T cell + OKT-3 antibody through tail vein, and the difference was statistically significant (P<0.001). The serum levels of human IL-2, human IFN-γ, human IL-15, mouse IL-6 and mouse GM-CSF in T cell+ OKT-3 group were (1 064.00±50.14), (1 285.00±193.90), (202.4±18.76), (1 478.00±289.20) and (350.70±42.27) pg/ml, respectively, higher than (22.67±6.36), (23.67±3.71), (44.33±14.45), (147.30±36.20), (138.00±22.74) pg/ml in T cell group (P<0.05). OKT-3 combined with human T cells caused a rapid increase in serum levels of human IL-2, human IFN-γ, mouse IL-6 and mouse GM-CSF, accompanied by an increase in body temperature and weight loss. CD19-targeting CAR-T cells were successfully constructed, and the positive rate of CAR-T cells was >30% detected by flow cytometry. ELISA results showed that in the presence of CD19 antigen, IL-2 and IFN-γ secreted by CAR-T19 cells co-incubated with Raji and Nalm were (561.00±37.07), (680.30±71.27), (369±25.71) and (523.00±26.31) pg/ml, respectively, higher than (55.00±20.53) and (64.00±7.55) pg/ml in the co-incubated with K562 group (P<0.001). Activated CAR-T19 cells were reinjected through the tail vein on the seventh day after tumor formation. Imaging experiments in mice showed that on the thirteenth day after tumor formation, the fluorescence intensities of tumors in the low-burden and high-burden groups were lower than on the seventh day of tumor inoculation, and the fluorescence intensity of tumors in the high-burden group decreased from 144.00±24.69 to 5.02±2.35 (P=0.005). The fluorescence intensity of low burden group decreased from 58.47±9.36 to 3.48±1.67 (P=0.004). The serum levels of T cell activation related cytokines IL-2, IL-15 and IFN-γ increased rapidly, and the secretion of monocyte related cytokines IL-16 and GM-CSF increased, accompanied by the typical characteristics of CRS such as increased body temperature and weight loss at 72 hours after injection of CAR-T19 cells. Conclusions: CAR-T cells targeting CD19 molecule are successfully constructed, and CRS phenomenon is verified in tumor-bearing mice by CAR-T cell re-infusion, providing an animal model for the mechanism of CAR-T treatment-related CRS and CRS prevention strategies.

PMID:34915632 | DOI:10.3760/cma.j.cn112152-20190916-00598

Zhonghua Jie He He Hu Xi Za Zhi. 2021 Dec 12;44(12):1090-1096. doi: 10.3760/cma.j.cn112147-20210406-00230.

ABSTRACT

Objective: To observe the expression of signal-regulatory protein α (SIRPα), surfactant protein (SP) A, and SPD by, and the phagocytic function of alveolar macrophages (AMs) in the rats exposed to biomass ambient particulate matter (BMF). Methods: Seventy-two male SD rats were randomly divided into BMF group and clean air group. Protein levels of SIRPα, SPA, and SPD in AMs were determined by Western blotting and immunofluorescent assay after 4 days, 1 month, and 6 months of BMF exposure. Fluorescent labeled Glucose aureus and Pseudomonas aeruginosa were used to detect the phagocytic ability of AMs in rats at three time points. Results: After 4 days of BMF exposure, there was no significant difference in the protein levels of SIRPα and SPD compared with the clean air group (P>0.05). The relative levels of SIRPα and SPD were (1.73±0.64) and (2.01±0.78) at 1 month of BMF exposure, and those at 6 months of BMF exposure were (1.49±0.28) and (1.48±0.34), both of which were higher than those in the clean air group (P<0.05). The relative level of Staphylococcus aureus median fluorescence intensity (MFI) and Pseudomonas aeruginosa MFI at 1 month BMF group were (0.56±0.16) and (0.80±0.09), and those at 6 months BMF group were (0.67±0.11) and (0.76±0.16), both of which were lower than those in clean air group, and the difference was statistically significant (P<0.05). Conclusions: BMF induces upregulation of SIRPα and SPD in AMs and inhibits the phagocytosis of AMs.

PMID:34915623 | DOI:10.3760/cma.j.cn112147-20210406-00230

Zhonghua Jie He He Hu Xi Za Zhi. 2021 Dec 12;44(12):1064-1070. doi: 10.3760/cma.j.cn112147-20210508-00312.

ABSTRACT

Objective: To analyze the efficacy and safety of Montgomery T-tube (T-tube) placement for benign complex subglottic tracheal stenosis. Methods: A retrospective analysis of the clinical data of 29 patients with benign complex subglottic tracheal stenosis receiving T-tube placement in Beijing Tiantan Hospital from May 2015 to December 2019. The causes were postintubation tracheal stenosis [27 cases (93.1%), including 21 cases (72.4%) of tracheal stenosis after tracheotomy, 6 cases (20.7%) of tracheal stenosis after tracheal intubation], cervical post-traumatic tracheal stenosis (1 case, 3.4%) and tuberculous tracheal stenosis (1 case, 3.4%), respectively. Three-dimensional reconstruction of tracheal computerized tomography (CT) and bronchoscopy were used to grade the stenosis according to Cotton-Myer classification system before bronchoscopic intervention. The degree of stenosis was Cotton-Myer grade Ⅱ (7 cases, 24.1%), grade Ⅲ (11 cases, 37.9%) and grade Ⅳ (11 cases, 37.9%), respectively. All cases received placement of T-tubes and follow-up. Fisher’s exact test was used for comparison between groups. Results: T-tube placement was performed 39 times in 29 patients. T-tubes were successfully placed for 24 cases (82.8%). The main complication during the operation was tracheal mucosal tear (6 cases, 20.7%), which resolved in all cases within 2 weeks. The main postoperative complication was secretion retention (27 cases, 93.1%), which was relieved after home nebulization treatment in 26 cases; and followed by granulation hyperplasia, especially located in T-tube upper margin (12 cases, 41.4%), of which 8 cases were cured after bronchoscopic intervention. None of the patients had T-tube migration. There were no statistically significant differences in the success rate of T-tube placement and the incidence of major complications in patients with benign complex subglottic tracheal stenosis with different degrees of stenosis. After 18 months to 24 months of follow-up, attempt was made to remove the T-tube in 9 patients but failed in 4 patients. The failure was due to collapse of the airway after the T-tube was removed. Conclusion: T-tube placement is a safe and reliable treatment for benign complex subglottic tracheal stenosis with high efficiency and manageable complications.

PMID:34915619 | DOI:10.3760/cma.j.cn112147-20210508-00312