[COVID-19 treated with oral Nirmatrelvir-Ritonavir in 3 children].

Objective: To summarize the application experience and the therapeutic effect of Nirmatrelvir-Ritonavir (trade name: Paxlovid) for COVID-19 in children. Methods: A retrospective analysis was performed on the clinical data, including collecting the clinical manifestations and clinical outcomes, dynamically monitoring the blood routine, hepatic and renal function and SARS-CoV-2 nucleic acid results, and observing the related side effects during the treatment, etc, of 3 cases with COVID-19 treated with Paxlovid admitted to Shanghai Children's Hospital (designated referral hospital for SARS-CoV-2 infection in Shanghai) from May 1st to June 1st, 2022. Results: The 3 cases were 12, 14, 17 years of age, among which 2 cases were males, 1 case was female. All 3 cases were mild cases with underlying diseases and risk of developing into severe COVID-19, with symptoms of high fever, sore throat and dry cough. The treatment of Paxlovid at 3rd day of symptom onset contributed to the symptom-free after 1-2 days and negative results of SARS-CoV-2 nucleic acid after 2-4 days. All patients had no adverse manifestations of gastrointestinal tract and nervous system but a case had little skin rashes, which recovered after the withdrawal of Paxlovid. Three cases had normal hepatic and renal function during the Paxlovid treatment. At 3 months after discharge, no clinical manifestations of post-COVID syndrome were found in all 3 cases. Conclusion: Paxlovid was effective and relatively safe in the treatment of 3 children with COVID-19.

[Clinical application of a prefabricated interocclusal recording cap for making interocclusal records of implant-supported fixed prostheses].

Objective: To use a self-developed, prefabricated cap for making interocclusal records in implant-supported fixed prosthetic treatment, and to evaluate its effect of clinical application and accuracy of transferring intra-oral intercuspal position. Methods: Series of prefabricated caps for occlusal recording of implant-supported fixed prostheses were designed based on the healing abutments, and fabricated with three-dimensional (3D) printing. According to the inclusion and exclusion criteria, 12 partially edentulous patients who visited the Department of Prosthodontics, Peking University School and Hospital of Stomatology between November 2020 and September 2021, had lost no fewer than 2 contiguous teeth in distal extension (Kennedy Class Ⅰ or Ⅱ), and had received implant placement 3 months ago were enrolled. Self-control study design was used. Two occlusal records of each included case were obtained by the following 2 methods: for the test group, appropriate prefabricated caps were used; and for the control group, polyvinyl siloxane occlusal record was directly set on the healing abutments. The working casts were mounted on the mechanical articulator using the 2 groups of occlusal records successively. Accuracy of occlusal relationship of the mounted casts was evaluated. Diagnostics test was performed to obtain the sensitivity and positive predictive value, which were determined in photographs by comparing the intra-oral occlusal contact points with those in the mounted casts, point-by-point. Virtual casts were taken by intraoral and extraoral scans in intercuspal position and imported to Geomagic Studio 2014. Then the root mean square values of occlusal clearance space between the upper and lower occlusal surfaces of remaining posterior teeth, and the deviations of the interocclusal position of the occlusal surfaces of the remaining teeth in the mandibular arches when superimposing the maxillary arches of the intraoral and extraoral scans were calculated. As a self-control design, paired t test was used. Results: Twelve participants were enrolled, including 3 men and 9 women aged (52.6±12.1) years, and 36 missing teeth. The prefabricated caps could fit on the healing abutments with good retention and stability. The sensitivity of the test group (0.73±0.14) was significantly better than that of control group (0.63±0.12,P<0.01), with no significant difference in positive predictive value between the 2 groups (P>0.05). The deviations of the interocclusal position of the occlusal surfaces of the remaining teeth were (357.0±140.2) µm for the test group, and (399.4±206.3) µm for the control group, with no significant difference between them (P>0.05). Conclusions: Interocclusal position record based on prefabricated cap in this study for implant-supported fixed prosthetic treatment can improve the consistency between the intra-oral occlusion and the occlusion in dental casts. This technique has good accuracy, clinical convenience and usability.

[Surgical diagnosis and treatment of adult huge undifferentiated embryonal sarcoma of the liver].

Objective: To investigate the clinical characteristics of adult undifferentiated embryonal sarcoma of the liver (UESL). Methods: A retrospective analysis was performed on the clinical data of 5 patients with UESL who underwent surgical resection and were pathologically confirmed from January 2005 to December 2020 at the First and the Second Affiliated Hospital of Anhui Medical University. All the patients were female aged from 49 to 77 years old. Preoperative CT showed a solid cystic mass with low density and a slight density of cord like septum. Imaging findings were misdiagnosed as hepatocellular carcinoma or cystadenocarcinoma. CA125 was higher in 3 patients,and AFP in all patients was normal. Results: All patients were treated by surgery. The mean diameter of tumor was 20.2 cm (range:15.0 to 30.0 cm). All five patients had vimentin expression in immunohistochemistry. Three cases underwent complete resection of the tumor and achieved R0 resection,2 of them had tumor free survival until the end of the follow-up (89 and 55 months),the other 1 case died from renal cell carcinoma 158 months later. The remaining 2 cases were radically resected,but the tumors were ruptured during operation,and relapsed after 2 months and 19 months respectively. The overall survival was 3 and 26 months respectively. Conclusions: Radical hepatectomy is the first choice for treatment of UESL. Intraoperative tumor rupture should be avoided and implant metastasis is a major factor affecting the prognosis of UESL.

[Morphology accuracy evaluation of direct composite occlusal veneer using two types of modified stamp-technique].

OBJECTIVE: To evaluate the morphology accuracy of direct occlusal veneer using two types of modified stamp-technique, comparing the Results of two types of stamp and different composite resin. METHODS: Model scanner was used to get the original data from the standard resin teeth in plastic model. Two types of stamps were made: solid silicon stamp and transparent silicon stamp. In the study, 54 resin tooth were randomly divided into 9 groups: Groups 1-8 were restored by direct composite resin, using general and bulk-filled composite resin in occlusal veneer (1 mm or 2 mm) with two types of stamp-technique (the solid silicon, and the transparent silicon), and the control group was restored by indirect way using CAD/CAM composite resin restoration by biocopy technique to mimic the original shape of the teeth. After the resin teeth were prepared for occlusal veneer, the direct and indirect composite resins were restored. After the restoration was finished, the data were obtained again by the same model scanner in the plastic model. 3D comparisons were made using the original and restoration data, the average difference and the root mean square of difference (RMS) were recoded from the software. The RMS of all the groups were analyzed using one way ANOVA (α=0.05). RESULTS: The RMS of occlusal surface in solid silicon stamp group was (0.136±0.031) mm, in transparent silicon group was (0.130±0.024) mm, and in control group was (0.130±0.009) mm. There were no significant difference. While the RMS of buccal/lingual surface in solid silicon stamp group was the smallest [(0.135±0.020) mm, P < 0.05], and in transparent silicon group it was (0.147±0.021) mm, and control group (0.153±0.014) mm. The general composite resin using the two types of stamp had the largest occlusal RMS in 2 mm occlusal veneer, which were significantly larger than control group (P < 0.05). CONCLUSION: The direct occlusal veneer using two types of modified "stamp-technique" had relatively good morphology accuracy. Direct occlusal veneer using bulk-filled composite resin made with two types of stamp technique had even more accurate morphology than using general composite resin. The solid silicon stamp had a better morphology accuracy in buccal/lingual surface than the transparent silicon stamp.

Regenerative medicine, organ bioengineering and transplantation.

BACKGROUND: Organ transplantation is predicted to increase as life expectancy and the incidence of chronic diseases rises. Regenerative medicine-inspired technologies challenge the efficacy of the current allograft transplantation model. METHODS: A literature review was conducted using the PubMed interface of MEDLINE from the National Library of Medicine. Results were examined for relevance to innovations of organ bioengineering to inform analysis of advances in regenerative medicine affecting organ transplantation. Data reports from the Scientific Registry of Transplant Recipient and Organ Procurement Transplantation Network from 2008 to 2019 of kidney, pancreas, liver, heart, lung and intestine transplants performed, and patients currently on waiting lists for respective organs, were reviewed to demonstrate the shortage and need for transplantable organs. RESULTS: Regenerative medicine technologies aim to repair and regenerate poorly functioning organs. One goal is to achieve an immunosuppression-free state to improve quality of life, reduce complications and toxicities, and eliminate the cost of lifelong antirejection therapy. Innovative strategies include decellularization to fabricate acellular scaffolds that will be used as a template for organ manufacturing, three-dimensional printing and interspecies blastocyst complementation. Induced pluripotent stem cells are an innovation in stem cell technology which mitigate both the ethical concerns associated with embryonic stem cells and the limitation of other progenitor cells, which lack pluripotency. Regenerative medicine technologies hold promise in a wide array of fields and applications, such as promoting regeneration of native cell lines, growth of new tissue or organs, modelling of disease states, and augmenting the viability of existing ex vivo transplanted organs. CONCLUSION: The future of organ bioengineering relies on furthering understanding of organogenesis, in vivo regeneration, regenerative immunology and long-term monitoring of implanted bioengineered organs.

[Effect of TUTF1 expression on the proliferation, apoptosis and prognosis of hepatocellular carcinoma cells].

Objective: To study the relationship between the expressions of tuftelin 1 (TUFT1) and the clinicopathological features of hepatocellular carcinoma and its effect on proliferation and apoptosis, and to explore the relationship between TUFT1 with the development of hepatocellular carcinoma. Methods: Immunohistochemistry was used to detect the expression of TUFT1 in 98 cases of hepatocellular carcinoma and 30 cases of adjacent normal tissues. Quantitative real-time PCR (qRT-PCR) was used to detect the expression of TUFT1 in HCC cell line. The expression of TUFT1 in SMMC-7221 cell lines was down-regulated by lentiviral vector. Cell proliferation assay, clonogenic assay, cell apoptosis assay and cell cycle assay were used to detect proliferation, apoptosis, and cell cycle changes of hepatocarcinoma cells after TUFT1-down-regulation. Statistics were performed using the χ2 test and the t-test. Results: Among the 98 cases of hepatocellular carcinoma, 65 cases (66.33%) were positive for TUFT1, and in 30 cases of adjacent normal tissues, 6 cases (16.67%) were positive for TUFT1, and the difference was statistically significant (χ (2) = 19.956, P < 0.05). The expression of TUFT1 in HCC tissues was related to tumor size, tumor stage, recurrence and metastasis (χ(2) = 6.214, 8.066, 14.400, P < 0.05). After lentiviral vector mediated downregulation of TUFT1 expression in SMMC -7221 cells, the cell proliferation rate [(18.62% ± 0.15%) vs. (67.91% ± 0.62%), P < 0.05], clonality [(8.10% ± 0.80%) vs. (50.80% ± 1.60%), P < 0.05] and G1 phase cells [(36.71% ± 0.69%) vs. (44.65% ± 0.73%), P < 0.05] were significantly decreased, whereas the G2 phase cells [ (15.44% ± 0.53%) vs. (22.31% ± 0.20%), P < 0.05] and the rate of apoptosis [(3.45% ± 0.18%) vs. (5.45% ± 0.06%), P < 0.05] was significantly increased compared with the control group of HCC cells, and the differences were statistically significant. Conclusion: The expression of TUFT1 is highly expressed in hepatocellular carcinoma tissues. Furthermore, the expression of TUFT1 promotes HCC cell proliferation, inhibits the apoptosis, and is poor prognostic factor of hepatocellular carcinoma.

[Ki-67 expression and its effect on response to neo-adjuvant chemotherapy in invasive breast cancer].

Objective: To investigate the response to neoadjuvant chemotherapy (NAC) among different molecular subtypes of breast cancers using molecular classification with Ki-67 (ER+ PR+ HER2+ Ki-67) or without Ki-67 (ER+ PR+ HER2). Methods: One hundred and twenty-seven cases of invasive breast cancer confirmed by core needle biopsy before NAC were collected from January 2007 to December 2009 and diagnosed at West China Hospital, Sichuan University. The cases were classified into different molecular subtypes using molecular classifications with or without Ki-67. Their clinical and pathological response to NAC was evaluated and compared. Results: The different subtypes using both molecular classifications showed significant difference in clinical response(with Ki-67: χ(2)=22.40, P<0.01; without Ki-67: χ(2)=9.202, P=0.027)but not pathological(P>0.05) response to NAC. By multivariate analysis, Ki-67 was predictive for a clinical complete response (P=0.041) and clinical overall response (P<0.01); also Ki-67 was the only clinicopathological factor predictive of pathological response(P=0.041). Conclusion: The molecular classification with Ki-67 is better to predict breast cancers responsiveness to NAC than the molecular classification without Ki-67.

[Interaction between APOB gene polymorphism and risk factors in coronary heart disease patients without lipid-lowering treatment].

Objective: To investigate the association between APOB gene R532W polymorphism and the risk of coronary heart disease (CHD) in patients without lipid-lowering treatment and to analyze the interactions between the variation of R532W and different risk factors of CHD. Methods: CHD and non-CHD were diagnosed according to coronary artery angiography (CAG) and/or coronary computed tomography angiogram (CTA) results, as well as clinical features. Blood samples from 771 CHD patients and 772 age- and sex-matched non-CHD controls, who never accepted any lipid-lowering treatments, were collected. R532W was genotyped by HumanExome BeadChip at BGI and strict quality control was made. Firstly, the association between R532W polymorphism and the risk of CHD in 3 genetic models (GA+ AA vs.GG, AA vs. GG+ GA, AA vs. GA vs. GG) after adjusting confounding factors was explored. Then, the interactions between the variation of this loci and risk factors related to CHD were investigated. Results: (1) Total cholesterol (TC) levels were significantly lower in AA genotype than in GA genotype in the total cohort and non-CHD controls, but was similar among the 3 genotypes in CHD patients. (2) R532W GG, GA and AA distribution was 80.7%, 18.2% and 1.2% in CHD patients, and 74.6%, 23.8% and 1.6% in non-CHD controls (P<0.05). (3) R532 polymorphism was related to the incidence of CHD in the dominant model, and A-allele carriers were related to about 35% reduced risk of CHD (OR=0.653, 95% CI 0.502-0.849, P=0.001) after adjusting for confounding factors. (4) R532W polymorphism had positive interactions with hypertension (1.452) and smoke (1.077), while negative interaction with diabetes (0.553) in the occurrence of CHD. Conclusions: APOB gene R532W polymorphism is related to TC levels in Chinese north Han population. A-allele carries of R532W loci is linked with reduced risk of CHD in the absence of lipid-lowering treatment. R532W polymorphism has a positive additive interaction with hypertension and smoke, while a negative additive interaction with diabetes mellitus in the occurrence of CHD.

Improvement of 7α-methoxycephalosporins production by overexpression of cmcJ and cmcI controlled by promoter ermEp* in Streptomyces clavuligerus.

AIM: This study aimed to improve the efficiency of bioconversion of cephalosporin C to 7α-methoxycephalosporin C. METHODS AND RESULTS: We performed the genetic modulation of the expression level of tailoring genes cmcI and cmcJ, which are responsible for the methoxylation of cephalosporin C, to improve the efficiency of bioconversion in the recombinant strains. The results showed that the coordinate adjustment of the enzyme amounts of CmcI and CmcJ in the host strain by placing the ermEp* promoter in the upstream of both cmcI and cmcJ genes in their expression cassette can improve the efficiency of bioconversion from cephalosporin C to 7α-methoxycephalosporin C. Under the optimized cultivation condition, 2·0 g l(-1) of the substrate cephalosporin C can be transformed into 0·78 g l(-1) of 7α-methoxycephalosporin C by the extract of the recombinant strain Streptomyces clavuligerus DYG3003, in which the transcript ratio of cmcJ/cmcI has been engineered to 1·7 : 1. CONCLUSIONS: Coordinate adjustment of the enzyme amounts of CmcI and CmcJ in the host strain can greatly enhance the efficiency of bioconversion from cephalosporin C (CPC) to 7a-methoxycephalosporin (MCPC). SIGNIFICANCE AND IMPACT OF THE STUDY: As one kind of the most important ß-lactam antibiotics, 7α-methoxycephalosporins show stronger activity against penicillin-resistant bacteria than cephalosporins because of the higher stability of 7α-methoxycephalosporins to ß-lactamase. Our study provides a practical strategy to perform the industrial production of the clinically useful 7α-methoxycephalosporin C through biotransformation.

Dental abnormalities in eight captive giant pandas (Ailuropoda melanoleuca) in China.

Dental data from eight adult giant pandas (Ailuropoda melanoleuca) (four females and four males) were collected at the Beijing Zoo from February 2009 to July 2010. Examination findings were recorded in dental charts. All the pandas had different degrees of tooth wear. Incisors, canines and second premolars had the most abnormalities. Five animals had caries; molars were the most affected. Chip fractures were found in seven teeth (incisor, canine and premolar) of five pandas; two had complicated fractures of their canines. Premolars and other teeth were missing in three pandas. Different degrees of dental plaque and calculus were found in all animals. Two pandas had mild gingivitis; the depth of periodontal pockets in all pandas was normal (0-2 mm). Five pandas had abnormal tooth mobility. Samples of dental plaque were collected for microbial culture. Two hundred and fifty-three bacterial strains belonging to 48 species of 23 genera were isolated. Streptococcus, Moraxella, Peptostreptococcus and Porphyromonas were the dominant genera. Further research with larger sample sizes of free-ranging and captive giant pandas will be required in order to demonstrate the absence of the premolar tooth, tooth fractures and the relatively low prevalence of periodontal disease in captive giant pandas.

Discovery of N-(2-aminophenyl)-4-[(4-pyridin-3-ylpyrimidin-2-ylamino)methyl]benzamide (MGCD0103), an orally active histone deacetylase inhibitor.

The design, synthesis, and biological evaluation of N-(2-aminophenyl)-4-[(4-pyridin-3-ylpyrimidin-2-ylamino)methyl]benzamide 8 (MGCD0103) is described. Compound 8 is an isotype-selective small molecule histone deacetylase (HDAC) inhibitor that selectively inhibits HDACs 1-3 and 11 at submicromolar concentrations in vitro. 8 blocks cancer cell proliferation and induces histone acetylation, p21 (cip/waf1) protein expression, cell-cycle arrest, and apoptosis. 8 is orally bioavailable, has significant antitumor activity in vivo, has entered clinical trials, and shows promise as an anticancer drug.

Substituted N-(2-aminophenyl)-benzamides, (E)-N-(2-aminophenyl)-acrylamides and their analogues: novel classes of histone deacetylase inhibitors.

Inhibition of histone deacetylases (HDACs) is emerging as a new strategy in human cancer therapy. Novel 2-aminophenyl benzamides and acrylamides, that can inhibit human HDAC enzymes and induce hyperacetylation of histones in human cancer cells, have been designed and synthesized. These compounds selectively inhibit proliferation and cause cell cycle arrest in various human cancer cells but not in normal cells. The growth inhibition of 2-aminophenyl benzamides and acrylamides against human cancer cells in vitro is reversible and is dependent on the induction of histone acetylation. Compounds of this class can significantly reduce tumor growth in human tumor xenograft models.

(2-amino-phenyl)-amides of omega-substituted alkanoic acids as new histone deacetylase inhibitors.

A variety of omega-substituted alkanoic acid (2-amino-phenyl)-amides were designed and synthesized. These compounds were shown to inhibit recombinant human histone deacetylases (HDACs) with IC(50) values in the low micromolar range and induce hyperacetylation of histones in whole cells. They induced expression of p21WAF1/Cip1 and caused cell-cycle arrest in human cancer cells. Compounds in this class showed efficacy in human tumor xenograft models.

Development of potential antitumor agents. Synthesis and biological evaluation of a new set of sulfonamide derivatives as histone deacetylase inhibitors.

A series of sulfonamide hydroxamic acids and anilides have been synthesized and studied as histone deacetylase (HDAC) inhibitors that can induce hyperacetylation of histones in human cancer cells. The inhibition of HDAC activity represents a novel approach for intervening in cell cycle regulation. The lead candidates were screened in a panel of human tumor and normal cell lines. They selectively inhibit proliferation, cause cell cycle blocks, and induce apoptosis in human cancer cells but not in normal cells. The structure-activity relationships, the antiproliferative activity, and the in vivo efficacy are described.

[Cerebellar infarction due to vertebral artery dissection in a girl].

We report here a case of vertebral artery dissection, which is rare in childhood. A 12-year-old, previous healthy girl was admitted to our hospital with symptoms of vertigo, tinnitus, hearing loss, nausea and vomiting. Although there was neither higher cortical dysfunction, motor weakness, sensory disturbance nor slurred speech. She could not stand up because of severe vertigo. Cranial magnetic resonance imaging (MRI) revealed a subacute cerebellar infarct. A left vertebral artery angiogram on the hospital day 3 demonstrated a sharp narrowing at the C1-C2 level. After an anticoagulant therapy for about 2 weeks, all the symptoms disappeared except for mild tinnitus. Two months later, a left vertebral artery angiogram showed an abrupt occlusion at the C1 level. MRI T1-weighted images demonstrated a thrombus within the false lumen of the dissected vessels. A flow void revealed the patency of the residual true lumen. From these findings, we made a diagnosis of vertebral artery dissection, which was considered to have caused cerebellar infarction. The patient was mostly normal at discharge, and 100 mg/day of aspirin has been given until present.

Sequence variation and genetic diversity in the giant panda.

About 336-444 bp mitochondrial D-loop region and tRNA gene were sequenced for 40 individuals of the giant panda which were collected from Mabian, Meigu, Yuexi, Baoxing, Pingwu, Qingchuan, Nanping and Baishuijiang, respectively. 9 haplotypes were found in 21 founders. The results showed that the giant panda has low genetic variations, and that there is no notable genetic isolation among geographical populations. The ancestor of the living giant panda population perhaps appeared in the late Pleistocene, and unfortunately, might have suffered bottleneck attacks. Afterwards, its genetic diversity seemed to recover to some extent.