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1.
World J Clin Cases ; 12(15): 2655-2663, 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38817237

RESUMO

BACKGROUND: High-grade B-cell lymphoma (HGBL) is an unusual malignancy that includes myelocytomatosis viral oncogene (MYC), B-cell lymphoma-2 (BCL-2), and/or BCL-6 rearrangements, termed double-hit or triple-hit lymphomas, and HGBL-not otherwise specific (HGBL-NOS), which are morphologically characteristic of HGBL but lack MYC, BCL-2, or BCL-6 rearrangements. HGBL is partially transformed by follicular lymphoma and other indolent lymphoma, with few cases of marginal zone lymphoma (MZL) transformation. HGBL often has a poor prognosis and intensive therapy is currently mainly advocated, but there is no good treatment for these patients who cannot tolerate chemotherapy. CASE SUMMARY: We reported a case of MZL transformed into HGBL-NOS with TP53 mutation and terminal deoxynucleotidyl transferase expression. Gene analysis revealed the gene expression profile was identical in the pre- and post-transformed tissues, suggesting that the two diseases are homologous, not secondary tumors. The chemotherapy was ineffective and the side effect was severe, so we tried combination therapy including venetoclax and obinutuzumab. The patient tolerated treatment well, and reached partial response. The patient had recurrence of hepatocellular carcinoma and died of multifunctional organ failure. He survived for 12 months after diagnosis. CONCLUSION: Venetoclax combined with obinutuzumab might improve the survival in some HGBL patients, who are unsuitable for chemotherapy.

2.
Pest Manag Sci ; 79(10): 3808-3818, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37209281

RESUMO

BACKGROUND: Some traditional pesticide formulations are inefficient, leading to excessive use and abuse of pesticides, which in turn effects environment. Intelligent release pesticide formulations are ideal for improving pesticide utilization and persistence while reducing environmental pollution. RESULTS: We designed a benzil-modified chitosan oligosaccharide (CO-BZ) to encapsulate avermectin (Ave). Ave@CO-BZ nanocapsules are prepared based on a simple interfacial method via cross-linking of CO-BZ with diphenylmethane diisocyanate (MDI). The Ave@CO-BZ nanocapsules have an average particle size of 100 nm and exhibited a responsive release performance for ROS. The cumulative release rate of nanocapsules at 24 h with ROS increased by about 11.4% compared to that without ROS. The Ave@CO-BZ nanocapsules displayed good photostability. Ave@CO-BZ nanocapsules can penetrate root-knot nematodes more easily and exhibited better nematicidal activity against root-knot nematodes. The pot experiment showed that the control effect of Ave CS at low concentration was 53.31% at the initial stage of application (15 d), while Ave@CO-BZ nanocapsules was 63.54%. Under the same conditions, the control effect of Ave@CO-BZ nanocapsules on root-knot nematodes was 60.00% after 45 days of application, while Ave EC was only 13.33%. The acute toxicity experiments of earthworms showed that the toxicity of nanocapsules was significantly lower than that of EC. CONCLUSION: The ROS-responsive nanocapsules can improve the utilization of pesticides and non-target biosafety. This modified chitosan oligosaccharide has great potential as a bio stimuli-responsive material, and this simple and convenient method for preparing Ave@CO-BZ nanocapsules provides a direction for the effective utilization of pesticides. © 2023 Society of Chemical Industry.


Assuntos
Quitosana , Nanocápsulas , Praguicidas , Praguicidas/toxicidade , Espécies Reativas de Oxigênio , Oligossacarídeos
3.
J Colloid Interface Sci ; 629(Pt A): 926-937, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36152617

RESUMO

Droplet rebound from hydrophobic leaves is a major factor influencing pesticide utilization. The use of a surfactant is a major strategy to reduce droplet rebound, promoting pesticide deposition on hydrophobic agricultural plant leaves. However, most surfactants known to regulate droplet rebound are either anionic or cationic. In this study, ethoxylated propoxylated 2-ethyl-1-haxanol (EH 6) was identified as a nonionic surfactant that inhibits droplet rebound while promoting the complete spreading of the droplet on hydrophobic leaves. Compared with the widely reported nonionic surfactant Tween 20, EH 6 performs better at concentrations above 0.3%. This phenomenon can be attributed to the rapid migration of EH 6 from the bulk to the newly generated interface, significantly reducing the surface tension. We introduce a simple and effective strategy that can be used to enhance droplet deposition on hydrophobic plant surfaces, which may offer future economic and environmental benefits.


Assuntos
Praguicidas , Polissorbatos , Folhas de Planta/química , Propriedades de Superfície , Tensoativos/química , Interações Hidrofóbicas e Hidrofílicas
4.
World J Clin Cases ; 10(28): 10193-10200, 2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36246799

RESUMO

BACKGROUND: Extranodal natural killer/T cell lymphoma, nasal type (ENKL) is a highly aggressive malignancy characterized by its association with Epstein-Barr virus (EBV) and extranodal involvement, which shows a poor clinical outcome. Although L-asparaginase-based chemotherapy has improved the response rates of relapsed/refractory (R/R) ENKL, relapse occurs in up to 50% of patients with disseminated disease. CASE SUMMARY: Immune evasion has emerged as a critical pathway for survival in ENKL and may be effectuated via STAT3-driven upregulation of programmed cell death ligand 1 (PD-L1) or other molecular pathways. Anti-PD-1 is effective for R/R ENKL with EBV-driven upregulation of PD-L1 expression. Anti-PD-1 combined with decitabine showed positive preliminary results in a patient with R/R ENKL and resistance to anti-PD-1. CONCLUSION: The treatment experience, in this case, demonstrated the potential ability of decitabine combined with PD-1 inhibitor to treat R/R ENKL, thus providing a new treatment strategy for this tumor.

5.
World J Clin Cases ; 10(29): 10655-10662, 2022 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-36312466

RESUMO

BACKGROUND: BCR-ABL-negative myeloproliferative neoplasms (MPNs) are clonal hematopoietic stem cell disorders characterized by the proliferation of one or more myeloid lineages and by mutually exclusive JAK2 V617F, CALR, and MPL[A1] mutations. The combination of MPN and thalassemia is extremely unusual. Several cases with myeloproliferative neoplasms and ß-thalassemia have been reported. However, these have not been extensively reviewed. The present report describes two cases of myeloproliferative neoplasms complicated with ß-thalassemia and reviews all similar cases reported in the literature. CASE SUMMARY: We report two patients who were diagnosed with myeloproliferative neoplasms complicated with ß-thalassemia. Both patients had abnormal increases in platelet counts. Based on bone marrow pathology and molecular biology assessment, we made the diagnosis of myeloproliferative neoplasms complicated with ß-thalassemia. The female patient was given hydroxyurea and interferon, which enabled good control of her blood counts; the male patient was given ruxolitinib tablets, thalidomide tablets, and interferon to control the condition, but the patient poorly responded to drug treatment and died of gastrointestinal bleeding six months later. CONCLUSION: Given the findings of our cases and the literature review, we hypothesize that myeloproliferative neoplasms complicated with ß-thalassemia can lead to rapid disease progression and a poor prognosis.

6.
World J Clin Cases ; 10(21): 7502-7508, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-36157987

RESUMO

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is a common aggressive non-Hodgkin's lymphoma (NHL), accounting for 30%-40% of adult NHL. Primary testicular (PT) lymphoma is an uncommon extranodal disease representing approximately 1%-2% of lymphoma. Approximately 30%-40% of patients are refractory to frontline therapy or relapse after complete remission. Refractory DLBCL responds poorly to other lines of chemotherapy, and experiences short-term survival. CASE SUMMARY: We present a 41-year-old male patient who was diagnosed with PT-DLBCL. Further disease progression was observed after multiline chemotherapy. Chimeric antigen receptor T cells (CAR-T) therapy salvaged the patient. Unfortunately, a new mass was observed in the right adrenal area after six months. The patient was administered programmed cell death protein-1 (PD-1) inhibitor therapy and maintained progression-free survival at more than 17 mo of follow-up. CONCLUSION: Our findings support the potential benefit of CAR-T combined with PD-1 inhibitor therapies in this type of relapsed and refractory PT-DLBCL.

7.
World J Clin Cases ; 10(19): 6437-6445, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35979288

RESUMO

BACKGROUND: Undifferentiated embryonal sarcoma of the liver (UESL) is a rare and aggressive mesenchymal tumor in children. Herein, we describe our experience in neoadjuvant therapy (NAT) and subsequent surgery for the treatment of UESL in children. AIM: To evaluate the efficacy of NAT and explore a new choice for successful operation of UESL in children. METHODS: We retrospectively analyzed six patients newly diagnosed with unresectable UESL who received NAT and then surgery at our center between January 2004 and December 2019. The tumor was considered unresectable if it involved a large part of both lobes of the liver or had invaded the main hepatic vessels or inferior vena cava. The NAT included preoperative transcatheter arterial chemoembolization (TACE) and systemic chemotherapy. The patients were 4 boys and 2 girls with a mean age of 7 years. The longest tumor at presentation ranged from 8.6 to 14.8 cm (mean, 12 cm). Extrahepatic metastases were present in 2 cases. Preoperative systemic chemotherapy was administered 3 wk after TACE. Tumor resection was performed 3 wk after one or two cycles of NAT. The patients received systemic chemotherapy after surgery. RESULTS: All patients successfully underwent NAT and complete resection. The tumor volumes decreased by 18.2%-68.7%, with a mean decrease of 36% after 1 cycle of NAT (t = 3.524, P = 0.017). According to the Response Evaluation Criteria In Solid Tumors criteria, 4 patients had a partial response and underwent surgery, while 2 had stable disease and received another cycle of NAT before surgery. Massive tumor necrosis was seen on pathological examination of the surgical specimen: > 90% necrosis in two, > 50% necrosis in three, and 25% necrosis in 1, with an average of 71.8%. Post-NAT complications included fever, nausea and vomiting, and mild bone marrow suppression. Elevated alanine transaminase levels occurred in all patients, which returned to normal within 7-10 d after treatment. No cardiac or renal toxicity, severe hepatic dysfunction, bleeding and non-target embolization were observed in the patients. The median follow-up period was 8 years with an overall survival of 100%. CONCLUSION: NAT effectively reduced tumor volume, cleared the tumor margin, and caused massive tumor necrosis. This may be a promising choice for successful surgery of UESL in children.

8.
Front Aging Neurosci ; 14: 829573, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35462699

RESUMO

Neuronal ceroid lipofuscinosis (NCL) is composed of a group of inherited neurodegenerative diseases, with the hallmark of lipofuscin deposit (a mixture of lipids and proteins with metal materials) inside the lysosomal lumen, which typically emits auto-fluorescence. Adult-onset NCL (ANCL) has been reported to be associated with a mutation in the DNAJC5 gene, including L115R, L116Δ, and the recently identified C124_C133dup mutation. In this study, we reported a novel C128Y mutation in a young Chinese female with ANCL, and this novel mutation caused abnormal palmitoylation and triggered lipofuscin deposits.

9.
Pest Manag Sci ; 78(6): 2512-2522, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35318795

RESUMO

BACKGROUND: Unmanned aerial vehicles (UAVs) are widely used to improve the efficiency of pesticide applications. Low-volume spraying operations require more efficient deposition of droplets on the target surface. Therefore, pesticide deposition and retention on plant surfaces is a serious challenge for modern precision agriculture. Tank-mix adjuvants have been used to improve spray dilutions performance; however, their effects on the physicochemical properties of spray dilutions, dosage delivery, and pesticide dosage are unclear. RESULTS: Tank-mix adjuvant 8860 significantly improved the physicochemical properties of spray dilutions, inhibited spray droplets rebound, improved the wetting and spreading performance of spray dilutions on wheat leaves, and increased the effective deposition of tebuconazole on wheat leaves. Even when its dosage was reduced by one-third, the spray solution still showed excellent disease control and effective deposition of the active ingredient on wheat leaves. CONCLUSION: The use of appropriate tank-mix adjuvants in UAV-based plant protection for wheat can significantly improve the performance of spray dilutions, increase the efficiency of pesticide dosage delivery, and improve disease control. These adjuvants can also help reduce the pesticide use while ensuring their effectiveness. © 2022 Society of Chemical Industry.


Assuntos
Praguicidas , Agricultura , Praguicidas/análise , Triticum , Dispositivos Aéreos não Tripulados , Molhabilidade
10.
Chin J Integr Med ; 28(1): 20-27, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33837482

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of Pai-Neng-Da Capsule (, panaxadiol saponins component, PNDC) in combination with the cyclosporine and androgen for patients with chronic aplastic anemia (CAA). METHODS: A total of 79 CAA patients was randomly divided into 2 groups by a random number table, including PCA group [43 cases, orally PNDC 320 mg/d plus cyclosporine 5 mg/(kg·d) plus andriol 80 mg/d] and CA group [36 cases, orally cyclosporine 5 mg/(kg·d) plus andriol 160 mg/d]. All patients were treated and followed-up for 6 treatment courses over 24 weeks. The complete blood counts, score of Chinese medical (CM) symptoms were assessed and urine routine, electrocardiogram, hepatic and renal function were observed for safety evaluation. Female masculinization rating scale was established according to the actual clinical manifestations to evaluate the accurate degree of masculinization in female CAA patients treated by andriol. RESULTS: The effective rates were 88.1% (37/42) in the PCA group and 77.8% (28/36) in the CA group based on the standard for the therapeutic efficacy evaluation of hematopathy. There was no significant difference in the white blood cell (WBC) counts, platelet counts and hemoglobin concentration of peripheral blood between two groups after 6 months treatment. The masculinization score of female patient in the PCA group was significantly lower than the CA group (P<0.05). The mild abdominal distention was observed in 1 cases in the PCA group. In CA group, the abnormalities in the hepatic function developed in 2 cases and the renal disfunction was found in 1 case. CONCLUSION: The PNDC possesses certain curative effects in the treatment of CAA without obvious side-effects and can partially replace andriol thereby to reduce the degree of masculinization [Registried at Chinese Clinical Trial Registry (ChicTR1900028153)].


Assuntos
Anemia Aplástica , Saponinas , Androgênios , Anemia Aplástica/tratamento farmacológico , China , Feminino , Humanos , Medicamentos sem Prescrição , Saponinas/uso terapêutico
11.
Front Surg ; 9: 1088142, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36684371

RESUMO

Branchial cleft cysts are congenital diseases of the neck caused by abnormal embryonic development of the first to fourth branchial clefts. Most branchial cleft cysts are found in the head and neck, but branchial cleft cysts arising in posterior mediastinum are rarely reported. We report a 44-year-old Chinese man who was found to have a right-posterior mediastinal mass on chest computed tomography (CT) during a physical examination. The size of the mass was about 30.6 mm * 25.1 mm and enhanced CT of the chest showed an occupying lesion in the right parietal esophagus of the upper-posterior mediastinum with no significant enhancement. The patient was considered to have a neurogenic tumor with cystic change and underwent posterior mediastinal tumor resection. Postoperatively, pathological examination confirmed the final diagnosis of bronchial cleft cyst. The patient was discharged on the 7th day after surgery. One year postsurgery, no obvious recurrence was found in reexamination.

12.
Front Oncol ; 11: 762653, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868978

RESUMO

Most randomized trials for acute promyelocytic leukemia (APL) have investigated highly selected patients under idealized conditions, and the findings need to be validated in the real world. We conducted a population-based study of all APL patients in Zhejiang Province, China, with a total population of 82 million people, to assess the generalization of all-trans retinoic acid (ATRA) and arsenic as front-line treatment. The outcomes of APL patients were also analyzed. Between January 2015 and December 2019, 1,233 eligible patients were included in the final analysis. The rate of ATRA and arsenic as front-line treatment increased steadily from 66.2% in 2015 to 83.3% in 2019, with no difference among the size of the center (≥5 or <5 patients per year, p = 0.12) or age (≥60 or <60 years, p = 0.35). The early death (ED) rate, defined as death within 30 days after diagnosis, was 8.2%, and the 3-year overall survival (OS) was 87.9% in the whole patient population. Age (≥60 years) and white blood cell count (>10 × 109/L) were independent risk factors for ED and OS in the multivariate analysis. This population-based study showed that ATRA and arsenic as front-line treatment are widely used under real-world conditions and yield a low ED rate and a high survival rate, which mimic the results from clinical trials, thereby supporting the wider application of APL guidelines in the future.

13.
World J Clin Cases ; 8(11): 2332-2338, 2020 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-32548164

RESUMO

BACKGROUND: Transcatheter arterial chemoembolization (TACE) is a common treatment for inoperable malignant renal tumors. However, a series of complications may follow the TACE treatment. Spinal cord injury caused by the embolization of intercostal or lumbar arteries is extremely rare. CASE SUMMARY: We describe a case with quite uncommon spinal cord injury after TACE in a 3-year-old child with clear cell sarcoma of the kidney. Sensory impairment beneath the T10 dermatomes and paraplegia on the day after TACE were found in this patient. Unfortunately, sustained paraplegia still existed for more than 2 mo after TACE despite the large dose of steroids and supportive therapy. CONCLUSION: We should draw attention to an uncommon complication of paraplegia after TACE treatment in malignant renal tumors. Although it is rare, the result is disastrous.

14.
J Prosthodont ; 29(5): 409-414, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32237001

RESUMO

PURPOSE: Image registration of the optical intraoral scan to computed tomography image is essential for computer-guided implant surgery. The remaining teeth, which are considered to be congruent structures observed in the scan and radiographic images, are used to perform the image registration. The purpose of this study was to evaluate the effects of the distribution of matching fiducial points on the accuracy of the image registration. MATERIALS AND METHODS: A partially edentulous model with three anterior remaining teeth was prepared. Two mini dental implants were inserted in the posterior edentulous areas on both sides, and computed tomography and surface scan data were obtained. Three groups were set according to the distribution of the image matching points used: localized distribution, unilateral distribution, and bilateral distribution. Fifteen graduate students performed the registration process in each group using the same image matching method. The accuracy of image registration was evaluated by measuring the geometric discrepancies between the radiographic and registered scan images in the anterior, middle, and posterior regions. One-way and two-way analysis of variance with the Tukey HSD post hoc test were used for statistical analysis (α = 0.05) RESULTS: In general, the registration discrepancy was lowest in the bilateral distribution group, followed by the unilateral distribution and localized distribution groups (p< 0.001). In the regional analysis, the registration error tended to increase as the measurement region moved farther from the matching points. The distribution of the matching points and measurement regions had a statistical interaction in the accuracy of image registration. CONCLUSION: The accuracy of image registration of the surface scan to the computed tomography is affected by the matching point distribution that can be improved by placing artificial markers in the edentulous areas.


Assuntos
Implantes Dentários , Boca Edêntula , Cirurgia Assistida por Computador , Marcadores Fiduciais , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Tomografia Computadorizada por Raios X
16.
Med Sci Monit ; 24: 6255-6263, 2018 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-30194286

RESUMO

BACKGROUND The aim of this study was to investigate the effect of the JAK2/STAT3 pathway on the proliferation, cell cycle distribution, apoptosis, and oxidative stress of Raji cells via regulating HSP70 expression. MATERIAL AND METHODS Raji cells were divided into Blank, HSP70 siRNA, NC siRNA, AG490 (a JAK2/STAT3 signaling pathway inhibitor), and HSP70 siRNA + rh JAK2 (recombinant human JAK2) groups. HSP70 expression was detected by quantitative real-time reverse transcription-PCR (qRT-PCR); the expression levels of HSP70 and JAK2/STAT3 pathway-related proteins were evaluated by Western blotting; cell proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays; cell cycle distribution was observed by flow cytometry; cell apoptosis was tested by Annexin V-FITC/PI and Hoechst 33342/PI staining; reactive oxygen species (ROS) production was measured by dichloro-dihydro-fluorescein diacetate (DCFH-DA) assays; and MDA content and SOD and GSH-Px activities were determined using detection kits. RESULTS AG490 obviously down-regulated HSP70 expression, inhibited proliferation, induced cell cycle arrest at the G0/G1 phase, and promoted apoptosis in Raji cells; these effects were similar to the effects of HSP70 siRNA. Furthermore, ROS production and MDA content were increased in Raji cells treated with HSP70 siRNA or AG490, while SOD and GSH-Px activities were reduced. Raji cells in the HSP70 siRNA + rh JAK2 group did not significantly differ from those in the Blank group in regards to proliferation, cell cycle, apoptosis, and oxidative stress. CONCLUSIONS Blocking the JAK2/STAT3 signaling pathway may inhibit proliferation, induce cell cycle arrest, and promote oxidative stress and apoptosis in Raji cells via the down-regulation of HSP70.


Assuntos
Linfoma de Burkitt/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Janus Quinase 2/metabolismo , Estresse Oxidativo/fisiologia , Fator de Transcrição STAT3/metabolismo , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Linfoma de Burkitt/patologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/genética , Humanos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tirfostinas/farmacologia
17.
Front Microbiol ; 9: 1862, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30150977

RESUMO

Viral infections trigger the innate immune system, serving as the first line of defense, and are characterized by the production of type I interferon (IFN). Type I IFN is expressed in a broad spectrum of cells and tissues in the host and includes various subtypes (IFN-α, IFN-ß, IFN-δ, IFN-ε, IFN-κ, IFN-τ, IFN-ω, IFN-ν, and IFN-ζ). Since the discovery of type I IFN, our knowledge of the biology of type I IFN has accumulated immensely, and we now have a substantial amount of information on the molecular mechanisms of the response and induction of type I IFN, as well as the strategies utilized by viruses to evade the type I IFN response. Foot-and-mouth disease virus (FMDV) can selectively alter cellular pathways to promote viral replication and evade antiviral immune activation of type I IFN. RNA molecules generated by FMDV are sensed by the cellular receptor for pathogen-associated molecular patterns (PAMPs). FMDV preferentially activates different sensor molecules and various signal transduction pathways. Based on knowledge of the virus or RNA pathogen specificity as well as the function-structure relationship of RNA sensing, it is necessary to summarize numerous signaling adaptors that are reported to participate in the regulation of IFN gene activation.

19.
Gene ; 660: 62-67, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29574187

RESUMO

In this study, the systemic analyses of nucleotide, codon and amino acid usages for E2 gene of bovine viral diarrhea virus (BVDV) were carried out for estimating its genetic features. The nucleotide usage pattern at the first codon position was strongly influenced by the overall nucleotide composition, while the nucleotide usage patterns at the second and third codon positions seemed to have little link to the overall nucleotide composition. The result indicated that the mutation pressure from nucleotide composition constraint was not the single evolutionary force for genetic features of BVDV E2 gene. Just 18 out of 59 synonymous codons were similar with synonymous codon usage patterns for E2 gene between BVDV1 and BVDV2, while all synonymous codons which contain CpG dinucleotides were selected at the low level by E2 gene, suggesting that this gene suppressed the usages of codons containing CpG dinucleotides to regulate E2 gene replicate and transcript efficiently and avoid immune response from infected hosts. Amino acid usage patterns of E2 protein were generally different between BVDV1 and BVDV2. The patterns of synonymous codon and amino acid usages for E2 gene might be caused by the equilibrium of evolutionary forces from virus and host. Our work gave new investigations into the role of host origin in the formations of synonymous codon/amino acid usages and the evolutionary trend of BVDV E2 gene. The genetic characteristics that codon/amino acid usages of E2 gene adapted to the internal environment of individual animals might assist in understanding the changes of genetics and antigenicity for newly emerging BVDV.


Assuntos
Vírus da Diarreia Viral Bovina Tipo 1/genética , Vírus da Diarreia Viral Bovina Tipo 2/genética , Evolução Molecular , Mutação Silenciosa , Proteínas do Envelope Viral/genética , Animais , Bovinos
20.
J Basic Microbiol ; 58(5): 425-439, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29537653

RESUMO

The evolutionary factors in influencing the genetic characteristics of nucleotide, synonymous codon, and amino acid usage of 18 mycoplasma species were analyzed. The nucleotide usage at the 1st and 2nd codon position which determines amino acid composition of proteins has a significant correlation with the total nucleotide composition of gene population of these mycoplasma species, however, the nucleotide usage at the 3rd codon position which affects synonymous codon usage patterns has a slight correlation with either the total nucleotide composition or the nucleotide usage at the 1st and 2nd codon position. Other evolutionary factors join in the evolutionary process of mycoplasma apart from mutation pressure caused by nucleotide usage constraint based on the relationships between effective number of codons/codon adaptation index and nucleotide usage at the 3rd codon position. Although nucleotide usage of gene population in mycoplasma dominates in forming the overall codon usage trends, the relative abundance of codon with nucleotide context and amino acid usage pattern show that translation selection involved in translation accuracy and efficiency play an important role in synonymous codon usage patterns. In addition, synonymous codon usage patterns of gene population have a bigger power to represent genetic diversity among different species than amino acid usage. These results suggest that although the mycoplasmas reduce its genome size during the evolutionary process and shape the form, which is opposite to their hosts, of AT usages at high levels, this kind organism still depends on nucleotide usage at the 1st and 2nd codon positions to control syntheses of the requested proteins for surviving in their hosts and nucleotide usage at the 3rd codon position to develop genetic diversity of different mycoplasma species. This systemic analysis with 18 mycoplasma species may provide useful clues for further in vivo genetic studies on the related species.


Assuntos
Aminoácidos/genética , Composição de Bases/genética , Códon/genética , Genética Microbiana , Mycoplasma/genética , Nucleotídeos/genética , Sequência de Bases , Evolução Molecular , Frequência do Gene , Genes Bacterianos , Tamanho do Genoma , Genoma Bacteriano , Interações Hospedeiro-Patógeno/genética , Mutação , Análise de Componente Principal , Mutação Silenciosa
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