Growth and production evaluation of corn varieties and genotypes grow from seed with different storage ages

Quality seeds are one of the important elements in maintaining plant potential. One of the factors that can affect the growth potential and production of corn for each variety or genotype is the storage ages of the seeds. The purpose of this study was to obtain varieties or genotypes of corn that have the ability to grow and produce optimally from seeds that have been stored for one and six months. The research was conducted from August to December 2020 at the Cereal Research Institute, Maros, South Sulawesi, Indonesia. The seeds used were Variety of Srikandi Putih, Waxy Corn and Genotype of BC2F1. This study was designed using a randomized block design (RBD) with a two-factor. The first factor is the type of variety/genotype (V) consisting of Srikandi Putih (V1), Waxy Corn (V2) and Genotype of BC2F1 (V3). The second factor is seed storage ages (U) consisting of: 1 month (U1) and 6 months (U2). From these two factors, 6 treatment combinations were obtained which were repeated three times to obtain 18 experimental units. The data were analyzed with the SAS 9 for windows program. The results showed that the seed storage ages of 1 month could maintain the potential for plant height growth, and the weight of 100 seeds in the Variety of Srikandi Putih, Waxy Corn and Genotypes of BC2F1. Seed storage ages of 1 and 6 months did not affect the number of leaves and flowering time, but only 1 month of seed storage ages that could maintain the potential for seed production in Variety of Srikandi Putih, Waxy Corn and Genotypes of BC2F1.

Concurrent circulation of dengue serotype 1, 2 and 3 among acute febrile patients in Cameroon

Acute febrile patients presenting at hospitals in Douala, Cameroon between July and December 2020, were screened for dengue infections using RT-PCR on fragments of the 5’ and 3’ UTR genomic regions. In total, 12.8% (41/320) of cases examined were positive for dengue. Dengue virus 3 (DENV-3) was the most common serotype found (68.3%), followed by DENV-2 (19.5%) and DENV-1 (4.9%). Co-infections of DENV-3 and DENV-2 were found in 3 cases. Jaundice and headache were the most frequent clinical signs associated with infection and 56% (23/41) of the cases were co-infections with malaria. Phylogenetic analysis of the envelope gene identified DENV-1 as belonging to genotype V, DENV-2 to genotype II and DENV-3 to genotype III. The simultaneous occurrence of three serotypes in Douala reveals dengue as a serious public health threat for Cameroon and highlights the need for further epidemiological studies in the major cities of this region.

National Monitoring of Mosquito Populations and Molecular Analysis of Flavivirus in the Republic of Korea in 2020

The Korea Disease Control and Prevention Agency has established centers at 16 locations to screen vector populations and pathogens. The aims of this study were to determine the relative spatiotemporal distributions of mosquitoes that are flavivirus vectors, and to correlate them with instances of flaviviral disease in the Republic of Korea (ROK). We collected 67,203 mosquitoes in traps at 36 collection sites in 30 urban regions and migratory bird habitats in 2020. The trap index was 36.6, and the predominant mosquito species were the Culex pipiens complex, Armigeres subalbatus, Aedes albopictus, Aedes vexans, and Culex tritaeniorhynchus. The mosquitoes were pooled into 4953 pools to monitor flavivirus infection. We determined that the minimum infection rate of flavivirus was 0.01%. Japanese encephalitis virus (JEV) was detected in only seven pools of Culex orientalis from Sangju, and we isolated JVE from two pools. All detected JEV was found to be genotype V by phylogenetic analysis. To the best of our knowledge, this is the first study to isolate genotype V JVE from Culex orientalis in the ROK. Subsequent geographical and ecological studies on mosquitoes will help improve our understanding of the relative risk of flavivirus infection. Future studies should analyze mosquito species distribution and improve flavivirus monitoring and long-term surveillance.

Immunogenicity and Protective Ability of Genotype I-Based Recombinant Japanese Encephalitis Virus (JEV) with Attenuation Mutations in E Protein against Genotype V JEV

Genotype V (GV) Japanese encephalitis virus (JEV) has emerged in Korea and China since 2009. Recent findings suggest that current Japanese encephalitis (JE) vaccines may reduce the ability to induce neutralizing antibodies against GV JEV compared to other genotypes. This study sought to produce a novel live attenuated JE vaccine with a high efficacy against GV JEV. Genotype I (GI)-GV intertypic recombinant strain rJEV-EXZ0934-M41 (EXZ0934), in which the E region of the GI Mie/41/2002 strain was replaced with that of GV strain XZ0934, was introduced with the same 10 attenuation substitutions in the E region found in the live attenuated JE vaccine strain SA 14-14-2 to produce a novel mutant virus rJEV-EXZ/SA14142m-M41 (EXZ/SA14142m). In addition, another mutant rJEV-EM41/SA14142m-M41 (EM41/SA14142m), which has the same substitutions in the Mie/41/2002, was also produced. The neuroinvasiveness and neurovirulence of the two mutant viruses were significantly reduced in mice. The mutant viruses induced neutralizing antibodies against GV JEV in mice. The growth of EXZ/SA14142m was lower than that of EM41/SA14142m. In mouse challenge tests, a single inoculation with a high dose of the mutants blocked lethal GV JEV infections; however, the protective efficacy of EXZ/SA14142m was weaker than that of EM41/SA14142m in low-dose inoculations. The lower protection potency of EXZ/SA14142m may be ascribed to the reduced growth ability caused by the attenuation mutations.

Multifoci and multiserotypes circulation of dengue virus in Senegal between 2017 and 2018

Background Dengue fever is a mosquito born disease associated with self-limited to life threatening illness. First detected in Senegal in the nineteenth century, and despite its growing incidence this last decade, significant knowledge gaps exist in our knowledge of genetic diversity of circulating strains. This study highlights the circulating serotypes and genotypes between January 2017 and December 2018 and their spatial and temporal distribution throughout all regions of Senegal. Methods We used 56 dengue virus (DENV) strains for the analysis collected from 11 sampling areas: 39 from all regions of Senegal, and 17 isolates from Thiès, a particular area of the country. Two real time RT-qPCR systems were used to confirm dengue infection and corresponding serotypes. For molecular characterization, CprM gene was sequenced and submitted to phylogenetic analysis for serotypes and genotypes assignment. Results Three dengue virus serotypes (DENV-1–3) were detected by all used methods. DENV-3 was detected in 50% (28/56) of the isolates, followed by DENV-1 and DENV-2, each representing 25% (14/56) of the isolates. DENV-3 belongs to genotype III, DENV-1 to genotype V and DENV-2 to Cosmopolitan genotype. Serotype 3 was detected in 7 sampling locations and a co-circulation of different serotypes was observed in Thiès, Fatick and Richard-toll. Conclusions These results emphasize the need of continuous DENV surveillance in Senegal to detect DENV cases, to define circulating serotypes/genotypes and to prevent the spread and the occurrence of severe cases.

Miniature Erupting Volcano-Shaped Mitral Valve Aneurysm Secondary to Streptococcus agalactiae ST1656 Endocarditis: A Case Report

Mitral valve aneurysm (MVA) is a rare but life-threatening valvular pathologic entity most commonly associated with infective endocarditis (IE) of the aortic valve (AV). We describe a diabetic patient with ruptured anterior MVA secondary to capsular genotype V Streptococcus agalactiae (GBS) harboring novel ST1656 IE without AV involvement. Our patient presented with manifestations of various serious systemic and intracardiac complications, requiring early surgery, but ultimately died from non-cardiogenic causes. This case emphasizes the importance of treating MVA as a dangerous sequela of IE, of performing transesophageal echocardiography to make its accurate diagnosis and institute early surgical intervention, and of considering GBS as a rare but important causative agent of IE in elderly patients with comorbidities.

Concurrent circulation of dengue serotype 1, 2 and 3 among acute febrile patients in Cameroon

Acute febrile patients presenting at hospitals in Douala, Cameroon between July and December 2020, were screened for dengue infections using RT-PCR on fragments of the 5 and 3 UTR genomic regions. In total, 12.8% (41/320) of cases examined were positive for dengue. Dengue virus 3 (DENV-3) was the most common serotype found (68.3%), followed by DENV-2 (19.5%) and DENV-1 (4.9%). Co-infections of DENV-3 and DENV-2 were found in 3 cases. Jaundice and headache were the most frequent clinical signs associated with infection and 176 cases (55%) were co-infections with malaria. Phylogenetic analysis of the envelope gene identified DENV-1 as belonging to genotype V, DENV-2 to genotype II and DENV-3 to genotype III. The simultaneous occurrence of three serotypes in Douala reveals dengue as a serious public health threat for Cameroon and highlights the need for further epidemiological studies in the major cities of this region.

Một số đặc điểm sinh học phân tử của vi khuẩn đường ruột kháng kháng sinh nhóm β- lactam phổ rộng phân lập được tại cộng đồng xã Thanh Hà, huyện Thanh Liêm, tỉnh Hà Nam, năm 2015

Nghiên cứu sư dung các kỹ thuật trong phòng thí nghiệm nhằm mô tả một số đặc điểm sinh học phân tư của vi khuân đường ruột kháng kháng sinh nhóm β- lactam phổ rộng phân lập được tại cộng đồng xã Thanh Hà huyện Thanh Liêm, tỉnh Hà Nam, năm 2015. Kết quả nghiên cứu cho thấy tỷ lệ chủng vi khuân đường ruột (VKĐR) kháng kháng sinh (KKS) nhóm β- lactam phổ rộng mang gen TEM, CTX được xác định trên các loại mẫu khác nhau chiếm đa số, tỷ lệ tương ứng trên các mẫu lần lượt là 47,6% và 37,0% (265 mẫu phân người khoẻ mạnh); 42,4% và 55,6% (trên 125 mẫu phân động vật nuôi); 4,4% và 1,3% (trên 160 mẫu thức ăn đã chế biến), và 14,8%, 13,2% (trên 182 mẫu nước ăn uống/sinh hoạt). Phân tích mối liên hệ kiểu gen của 88 chủng VKĐR KKS nhóm cephalosporin thế hệ 3 bằng kỹ thuật PFGE cho thấy có 14 genotype được xác định bao gồm genotype I đến genotype XIV; trong đó, phát hiện được 28 chủng vi khuân có tương đồng trên 80% trong nhóm genotype V. Cần thực hiện các nghiên cứu tiếp theo để xác định mối liên quan và sự lây truyền của các chủng VKĐR kháng kháng sinh cephalosporin thế hệ 3 trong cộng đồng dân cư.

Adaptive Evolution of New Variants of Dengue Virus Serotype 1 Genotype V Circulating in the Brazilian Amazon

Dengue virus (DENV) is a mosquito-borne viral pathogen that plagues many tropical-climate nations around the world, including Brazil. Molecular epidemiology is a growing and increasingly invaluable tool for understanding the dispersal, persistence, and diversity of this impactful virus. In this study, plasma samples (n = 824) from individuals with symptoms consistent with an arboviral febrile illness were analyzed to identity the molecular epidemiological dynamics of DENV circulating in the Brazilian state of Amapá. Twelve DENV type 1 (DENV-1) genomes were identified, which were phylogenetically related to the BR4 lineage of genotype V. Phylodynamics analysis suggested that DENV-1 BR-4 was introduced into Amapá around early 2010, possibly from other states in northern Brazil. We also found unique amino acids substitutions in the DENV-1 envelope and NS5 protein sequences in the Amapá isolates. Characterization of the DENV-1 BR-4 sequences highlights the potential of this new lineage to drive outbreaks of dengue in the Amazon region.