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The main biopolymers in nature are oligonucleotides and polypeptides. However, naturally occurring peptide-nucleobase hybrids are rare. Here we report the characterization of the founding member of a class of peptide-nucleobase hybrid natural products with a pyrimidone motif from a widely distributed ribosomally synthesized and post-translationally modified (RiPP) biosynthetic pathway. This pathway features two steps where a heteromeric RRE-YcaO-dehydrogenase complex catalyzes the formation of a six-membered pyrimidone ring from an asparagine residue on the precursor peptide, and an acyl esterase selectively recognizes this moiety to cleave the C-terminal follower peptide. Mechanistic studies reveal that the pyrimidone formation occurs in a substrate-assisted catalysis manner, requiring a His residue in the precursor to activate asparagine for heterocyclization. Our study expands the chemotypes of RiPP natural products and the catalytic scope of YcaO enzymes. This discovery opens avenues to create artificial biohybrid molecules that resemble both peptide and nucleobase, a modality of growing interest.

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The ribosomally synthesized and post-translationally modified peptide (RiPPs) class of natural products has undergone significant expansion due to the rapid growth in genome sequencing data. Using a bioinformatics approach, we identify the dehydrazoles, a novel class of hypermodified RiPPs that contain both side chain dehydration of Ser residues, and backbone heterocyclization at Ser, Thr, and Cys residues to the corresponding azol(in)es. Structure elucidation of the hypermodified peptide carnazolamide, a representative class member, shows that 18 post-translational modifications are installed by just five enzymes. Complete biosynthetic reconstitution demonstrates that dehydration is carried out by an unusual DUF4135 dehydration domain fused to a zinc-independent cyclase domain (CcaM). We demonstrate that CcaM only modifies Ser residues that precede an azole in the core peptide. As heterocyclization removes the carbonyl following the Ser residue, CcaM likely catalyzes dehydration without generating an enolate intermediate. Additionally, CcaM does not require the leader peptide, and this core-dependence effectively sets the order for the biosynthetic reactions. Biophysical studies demonstrate direct binding of azoles to CcaM consistent with this azole moiety-dependent dehydration. Bioinformatic analysis reveals more than 50 related biosynthetic gene clusters that contain additional catalysts that may produce structurally diverse scaffolds.

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Objective:To investigate the efficacy of open exploration, ulnar osteotomy and annular ligament reduction (three-in-one surgery) in the treatment of chronic Monteggia fracture in children.Methods:The data were analyzed retrospectively of the 35 children with chronic Monteggia fracture who had been admitted to Department of Pediatric Orthopaedics, Tianjin University from June 2017 to September 2021. There were 22 boys and 13 girls, and 19 left and 16 right sides, with an age of (6.8±2.5) years. Anterolateral dislocation of the radial head occurred in 30 cases and anterolateral dislocation in 5 ones. The time from injury to operation was (17.9±9.9) months. All patients were treated with three-in-one surgery. The elbow flexion and extension, forearm rotation and The Hospital for Special Surgery (HSS) elbow score were measured and compared in all patients at 12 months after operation. Their complications were also recorded.Results:All children were followed up for 12 months. The osteotomy ends of the ulna achieved bony union 1.5 to 4.0 months after operation. The elbow extension (-1.0°±5.9°) and flexion (128.5°±4.9°) at 12 months after operation were significantly improved compared with those before operation (-9.3°±18.0° and 108.4°±17.3°) ( P<0.05). The forearm pronation (61.5°±19.4°) at 12 months after operation was significantly limited compared with that before operation (72.7°±22.4°) ( P<0.05). There was no significant difference between the forearm supination (86.7°±4.5°) at 12 months after operation and that before operation (81.0°±17.4°) ( P>0.05). The HSS elbow score at 12 months after operation (93.5±5.2) was significantly higher than that (80.6±9.3) before operation ( P<0.05). The efficacy evaluated by the HSS elbow score at 12 months after operation was excellent in 21 cases, good in 12 cases, and fair in 2 cases, giving an excellent and good rate of 94.3% (33/35). Postoperative re-subluxation was observed in one patient. Conclusion:Open exploration, ulnar osteotomy and annular ligament reduction are a safe and effective three-in-one surgery for chronic Monteggia fracture in children, because it may lead to significantly improved elbow flexion and extension after operation, though the forearm pronation may be limited.

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Lanthipeptides are a class of cyclic peptides characterized by the presence of one or more lanthionine (Lan) or methyllanthionine (MeLan) thioether rings. These cross-links are produced by α,ß-unsaturation of Ser or Thr residues in peptide substrates by dehydration, followed by a Michael-type conjugate addition of Cys residues onto the dehydroamino acids. Lanthipeptides may be broadly classified into at least five different classes, and the biosynthesis of classes I-IV lanthipeptides requires catalysis by LanC cyclases that control both the site-specificity and the stereochemistry of the conjugate addition. In contrast, there are no current examples of LanCs that occur in class V biosynthetic clusters, despite the presence of lanthionine rings in these compounds. In this work, bioinformatics-guided co-occurrence analysis identifies more than 240 putative class V lanthipeptide clusters that contain a LanC cyclase. Reconstitution studies demonstrate that the cyclase-catalyzed product is notably distinct from the product formed spontaneously. Stereochemical analysis shows that the cyclase diverts the final product to a configuration that is distinct from one that is energetically favored. Structural characterization of the final product by multi-dimensional NMR spectroscopy reveals that it forms a helical stapled peptide. Mutational analysis identified a plausible order for cyclization and suggests that enzymatic rerouting to the final structure is largely directed by the construction of the first lanthionine ring. These studies show that lanthipeptide cyclases are needed for the biosynthesis of some constrained peptides, the formations of which would otherwise be energetically unfavored.

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Mechercharmycin A (MCM-A) is a marine natural product belonging to a family of polyazole cyclopeptides with remarkable bioactivities and unique structures. Identification, heterologous expression, and genetic characterizations of the MCM biosynthetic gene cluster in Bacillus subtilis revealed that it is a ribosomally synthesized and post-translationally modified peptide (RiPP) possessing complex with distinctive modifications. Based on this heterologous expression system, two MCM analogs with comparable antitumor activity are generated by engineering the biosynthetic pathway. Combinatorial co-production of a precursor peptide with different modifying enzymes in Escherichia coli identifies a different timing of modifications, showing that a tRNAGlu-dependent highly regioselective dehydration is the first modification step, followed by polyazole formation through heterocyclization and dehydrogenation in an N- to C-terminal direction. Therefore, a rational biosynthetic pathway of MCMs is proposed, which unveils a subfamily of azol(in)e-containing RiPPs and sets the stage for further investigations of the enzymatic mechanism and synthetic biology.

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This review aims to interpret the interventions to improve physical function for children and young people with cerebral palsy, thus providing relevant suggestions.Relevant literatures published before November 2018 were systematically searched in Cochrane library, CINAHL, and Embase MEDLINE using the Grading of Recommendations Assessment, Development and Evaluation method.Consult with international experts and patients to assess evidence and recommend it.Based on 3 systematic reviews, 30 randomized clinical trials, and 5 pre-and post-treatment studies, a total of 13 recommendations were given.The guidelines recommend that, in order to achieve functional stan-dards, intervention measures should include, patient-selected goals, full-task practice in real-life settings, support for family empowerment, and a team approach.The age, ability, and child/family preferences were all needed to be considered.In order to improve walking ability, ground walking and treadmill training can be carried out.Various methods can promote the realization of hand use goals hand use, including the two-hand exercise training, constraint-induced moverment therapy, goal-oriented training and cognitive therapy.In terms of patient self-care, the guideline proposed that, the combination of full-task practice and auxiliary equipment can improve the independence of self-care and reduce the burden of care givers.Leisure goals could be achieved by the combination of the practice of the entire task with strategies to address environmental, personal, and social barriers.The intervention of children and adolescents with cerebral palsy should take into consideration of patient selection and the goal of full-task practice.The child/family preference, age and ability should be considered when clinical workers selecting specific interventions.

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The high mutation rate of COVID-19 and the prevalence of multiple variants strongly support the need for pharmacological options to complement vaccine strategies. One region that appears highly conserved among different genus of coronaviruses is the substrate binding site of the main protease (Mpro or 3CLpro), making it an attractive target for the development of broad-spectrum drugs for multiple coronaviruses. PF-07321332 developed by Pfizer is the first orally administered inhibitor targeting the main protease of SARS-CoV-2, which also has shown potency against other coronaviruses. Here we report three crystal structures of main protease of SARS-CoV-2, SARS-CoV and MERS-CoV bound to the inhibitor PF-07321332. The structures reveal a ligand-binding site that is conserved among SARS-CoV-2, SARS-CoV and MERS-CoV, providing insights into the mechanism of inhibition of viral replication. The long and narrow cavity in the cleft between domains I and II of main protease harbors multiple inhibitor binding sites, where PF-07321332 occupies subsites S1, S2 and S4 and appears more restricted compared with other inhibitors. A detailed analysis of these structures illuminated key structural determinants essential for inhibition and elucidated the binding mode of action of main proteases from different coronaviruses. Given the importance of main protease for the treatment of SARS-CoV-2 infection, insights derived from this study should accelerate the design of safer and more effective antivirals.

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AIM: To explore the association of single nucleotide polymorphisms (SNPs) in the IL33/IL1RL1 gene region with the susceptibility to Behcet's disease (BD) in a Chinese Han population. METHODS: A total of eight SNPs in the candidate gene region (rs11792633, rs7025417, rs10975519 and rs1048274 in IL33; rs2310220, rs12712142, rs13424006 and rs3821204 in IL1RL1) were genotyped in783 BD patients and 701 healthy controls by the Sequenom Mass Array iPLEX platform. RESULTS: A statistically significant association was observed between IL1RL1 rs12712142 and BD patients. The frequency of IL1RL1 rs12712142 variant allele A was significantly lower in BD patients than that in controls (OR=0.8, 95%CI: 0.69-0.94, Pc=0.039); the genotype distribution (Pc=0.043) and additive and dominant genetic model analyses (OR=0.8, 95%CI: 0.69-0.94, Pc=0.040 and OR=0.72, 95%CI: 0.58-0.88, Pc=0.011) also indicated a strong association between rs12712142 and BD patients. CONCLUSION: This is the first study to reveal the association between IL1RL1 rs12712142 variant allele A and the decreased risk of BD in the Chinese Han population, indicating a protective role of IL1RL1 in the pathogenesis of BD.

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Using a highly effective heterologous expression system, the YM-216391 (1) biosynthetic gene cluster was engineered to yield aurantizolicin (2) and the hybrid compound 3. Both of these compounds were isolated and fully structurally characterised and the bioactivity was evaluated. The results indicate that compound 3 exhibits significantly improved antitumor activity.

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BACKGROUND: Cleidocranial dysplasia (CCD) is an autosomal dominant disease that affects the skeletal system. Common symptoms of CCD include hypoplasia or aplasia of the clavicles, delayed or even absent closure of the fontanels, midface hypoplasia, short stature, and delayed eruption of permanent and supernumerary teeth. Previous studies reported a connection between CCD and the haploinsufficiency of runt-related transcription factor 2 (RUNX2). Here, we report a sporadic Chinese case presenting typical symptoms of CCD. METHODS: We made genetic testing on this sporadic Chinese case and identified a novel RUNX2 frameshift mutation: c.1111dupT. In situ immunofluorescence microscopy and osteocalcin promoter luciferase assay were performed to compare the functions of the RUNX2 mutation with those of wild-type RUNX2. RESULTS: RUNX2 mutation was observed in the perinuclear region, cytoplasm, and nuclei. In contrast, wild-type RUNX2 was confined in the nuclei, which indicated that the subcellular compartmentalization of RUNX2 mutation was partially perturbed. The transactivation function on osteocalcin promoter of the RUNX2 mutation was obviously abrogated. CONCLUSIONS: We identified a sporadic CCD patient carrying a novel insertion/frameshift mutation of RUNX2. This finding expanded our understanding of CCD-related phenotypes.

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Vogt-Koyanagi-Harada (VKH)syndrome is an autoimmune disease attacking against pigmented cells, resulting in blindness and usually affecting multiple organs including ears, meninges, hair and skin.Correct diagnosis and immediate treatment in the early stage is vital to visual prognosis.Currently, corticosteroids is first-line drug.In addition, VKH patients refractory to corticosteroids can choose other treatment such as immunosuppressive agents and biological agents.

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<p><b>BACKGROUND</b>Cleidocranial dysplasia (CCD) is an autosomal dominant disease that affects the skeletal system. Common symptoms of CCD include hypoplasia or aplasia of the clavicles, delayed or even absent closure of the fontanels, midface hypoplasia, short stature, and delayed eruption of permanent and supernumerary teeth. Previous studies reported a connection between CCD and the haploinsufficiency of runt-related transcription factor 2 (RUNX2). Here, we report a sporadic Chinese case presenting typical symptoms of CCD.</p><p><b>METHODS</b>We made genetic testing on this sporadic Chinese case and identified a novel RUNX2 frameshift mutation: c.1111dupT. In situ immunofluorescence microscopy and osteocalcin promoter luciferase assay were performed to compare the functions of the RUNX2 mutation with those of wild-type RUNX2.</p><p><b>RESULTS</b>RUNX2 mutation was observed in the perinuclear region, cytoplasm, and nuclei. In contrast, wild-type RUNX2 was confined in the nuclei, which indicated that the subcellular compartmentalization of RUNX2 mutation was partially perturbed. The transactivation function on osteocalcin promoter of the RUNX2 mutation was obviously abrogated.</p><p><b>CONCLUSIONS</b>We identified a sporadic CCD patient carrying a novel insertion/frameshift mutation of RUNX2. This finding expanded our understanding of CCD-related phenotypes.</p>

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?Acute retinal necrosis syndrome ( ARN) is a serious eye disease, which caused by Herpes virus mostly, with unknown pathogenesis. Because of the aggressive progression, treatment of ARN is difficult, and the blindness rate is extremely high. Current treatment strategies are the combination of the drug therapy and the operative treatment. Drugs commonly used are antiviral drugs, glucocorticoids, and antiplatelet drugs, and the operative treatment includes laser photocoagulation and vitrectomy.

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The study of mechanical properties on heart valves can provide an important theoretical basis for doctors to repair heart valves and prosthetic valve materials research. In this paper, we present the current status of the mechanical property study methods of heart valve, expound the methods and special requirements about uniaxial tensile test and biaxial tensile test of the heart valve, and further discuss several establishment methods of heart valve constitutive models. We also discuss the development trend of heart valve mechanics.

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Diagnosis of uveitis based on etiologies and entities is essential for the treatment of the uveitis patients. A careful and meticulous inquiry about history may provide important clue to the diagnosis. Careful and detailed clinical ocular examinations allow us to make a correct diagnosis in most uveitis patients. Auxiliary examinations and laboratory examinations chosen principally based on clinical manifestation enable us to make a definite diagnosis in almost all the uveitis patients.

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Uveitis is a group of common eye disease and is one of the major causes of blindness worldwide. Corticosteroids and immunosuppressive agents are commonly used for the treatment of uveitis. However, long-term application of these drugs frequently lead to numerous side effects. Recently, with the development of gene transfer techniques, viral vector mediated gene therapy has achieved remarkable success in experimental uveitis. Inhibition of ocular inflammation in animal models is obtained mainly by two ways: first, increase of the expression of different immune modulators including IL-10, IL-1Ra, IL-4 and IFN-alpha, or IL-27p28; secondly, induction of immune tolerance by transferring uveitis related antigens via viral vectors. Uveitis is characterized by long-lasting and recurrent, the unique properties of local administration, long-term effectiveness and minor side effects of gene therapy may provide a novel strategy for the treatment of the devastating uveitis.

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AIM: To explore the clinical value of serum soluble intercellular adhesion molecule-1 (sICAM-1) in patients with primary hepatocellular carcinoma (PHC) and its relationship with liver fibrosis. METHODS: The serun sICAM-1, PC III, IV-C, LN and HA level of 45 cases of patients with PHC, 30 cases of benign tumor and 35 cases of healthy people were determined by ELISA, the relationship between sICAM-1 and liver fibrosis was analyzed. RESULTS: The serum sICAM-1, PC III, IV-C, LN and HA levels of the PHC group were significantly higher than that of the benign tumor group and normal control group, compared the difference was significant (P<0.05); The serum markers was no significant difference between the benign tumor group and normal control group (P>0.05); The serum sICAM-1 was positively correlated with the PC III, IV-C, LN and HA (γ= 0.683, 0.575, 0.573 and 0.539, P<0.05). CONCLUSION: Detection of serum sICAM-1 has important clinical significance for assessing the PHC patient's condition, early diagnosing and treating liver cancer.

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Objective To evaluate the effect of greater trochanteric transfer for the treatment of coxa brevis in children and adolescents.Methods From August 2005 to January 2011,twenty patients (22 hips)with coxa brevis underwent greater trochanteric transfer.Among them 18 patients (20 hips) were available for evaluation,including 4 boys and 14 girls,with an average age of 11.4 years (range,7.5-15.0 years) at operation.Five cases (6 hips) were caused by Perthes disease,and 13 cases (14 hips) were caused by developmental dysplasia of hip.Four patients (4 hips) had undergone greater trochanteric epiphyseodesis ever before.All patients were fixed with tension screw after the deformity was corrected during the operation.After operation,the human plaster spica was used for 6 weeks in all patients.Results All patients were followed up for 14 to 79 months (average,31 months).At the last follow-up,fatigue or pain in the hips disappeared or improved in 13 patients.Sixteen patients had limping and positive Trendelenburg sign preoperatively,at the last follow-up 9 patients got improvement.Twelve patients (13 hips) had limitation of abduction of the hip,the average range of abduction was 25.38°±1.20°,which was improved to 45.38°±1.05° at the last follow-up.The average articulotrochanteric distance and ratio of the distance from the greater trochanter tip to femoral head center and the radius of the femoral head at the last follow-up was (17.47+3.14)mm and 2.10±0.21,respectively,there were statistical differences compared with those before operation [(-2.89±4.62) mm and 1.59±0.22,respectiovely].The average leg-length discrepancy at the last follow-up was (0.78t±0.26) cm,which had on statistical differences compared with that [(0.83 ±0.33) cm]before operation.Conclusion Greater trochanteric transfer for the treatment of coxa brevis in children and adolescents could improve the clinical symptom,recover the normal anatomy of the proximal femoral,restore the hip biomechanics environment,but could uot improve the leg-length discrepancy.

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<p><b>OBJECTIVE</b>To investigate the mechanism of decreasing the K562/ADM cells chemosensitivity by up-regulating expression of PTEN gene.</p><p><b>METHODS</b>K562/ADM cells were transient transfected with pGFP-PTEN or vector. The level of PTEN in K562/ADM cells was assayed by Western blot and RT-PCR. Cell viability on K562/ADM was determined by MTT assay. Cell apoptosis by flow cytometry. Activity of caspase-3 by Caspase Colorimetric Assay Kit. The proteins expression of LC3-I/II, Beclin1, p-Akt, p-p70S6K by Western blot. The autophagic vacuoles by MDC stain and Electron microscopy.</p><p><b>RESULTS</b>(1) The mRNA and protein levels of PTEN in K562/ADM cells transfected with pGFP-PTEN were significantly increased compared with the control (untreated and transfected with empty vector). (2) Enhanced expression of PTEN by gene transfection resulted in a reversal of resistance to ADM. Compared with empty vector group, cell viability decreased from (94.07 ± 2.6)% to (53.83 ± 4.2)%, the cell apoptotic rate increased from (11.89 ± 1.7)% to (43.69 ± 2.3)%, meanwhile, pretreated with caspase-3 inhibitor (Z-DEVE-FMK) didn't completely inhibit the cytotoxicity of ADM to K562/ADM cells. (3) After treated with ADM for 12 and 24 h, the activities of caspase-3 in PTEN-transfected K562/ADM cells increased compared with those in pGFP-transfected K562/ADM cells \[(2.27 ± 0.13) vs (1.19 ± 0.14)\] at 12h, \[(3.15 ± 0.08) vs (1.48 ± 0.05)\] at 24 h (P < 0.05). (4) The protein levels of LC3-II and Beclin1 in K562/ADM cells transfected with pGFP-PTEN were increased by 83% and 18% respectively, and the protein levels of p-Akt and p-p70S6K were declined by 96% and 87% respectively, compared with those in K562/ADM cells transfected with pGFP plasmid. (5) The upregulation of PTEN in K562/ADM cells improved the number of autophagic vacuoles compared with the empty vector group.</p><p><b>CONCLUSION</b>The upregulation of PTEN expression increases the chemosensitivity of K562/ADM to ADM, which may related with the inhibition of PI3K/AKT/mTOR pathway induced by PTEN gene transfection.</p>

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<p><b>BACKGROUND</b>Autosomal recessive polycystic kidney disease (ARPKD) is a rare inherited disease, which is a disorder with multiple organ involvement, mainly the kidney and liver. It is caused by mutations in the PKHD1 gene. Here, we reported the clinical characteristics of a case with ARPKD and analyze the genetic features of this patient as well as of his father using targeted exome sequencing and Sanger sequencing.</p><p><b>METHODS</b>Genomic DNA was extracted from peripheral blood leukocytes obtained from a patient with ARPKD. The mutations were identified using exome sequencing and confirmed by Sanger sequencing.</p><p><b>RESULTS</b>The patient was diagnosed as ARPKD based on ultrasonography and abdominal computed tomography which showed polycystic changes, multiple calcinosis of both kidneys, and multiple dilated bile ducts of the liver. Compound heterozygous PKHD1 gene mutations A979G and G5935A, which lead to substitution of an asparagine for an aspartate at amino acid 327 (N327D) and a glycine for an arginine at amino acid 1979 (G1979R) respectively, were identified using targeted exome sequencing and confirmed by Sanger sequencing for the patient. In addition, the father of the patient was identified to be a carrier of heterozygous A979G mutation of this gene.</p><p><b>CONCLUSIONS</b>We identified that the compound heterozygous PKHD1 gene mutations are the molecular basis of the patient with ARPKD. Targeted exome sequencing is suitable for genetic diagnosis of single-gene inherited diseases like ARPKD in which the pathogenic gene is a large.</p>

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