The pandemic caused by the worldwide spread of the coronavirus, which first appeared in 2019, has been named coronavirus disease 19 (COVID-19). More than 4.5 million deaths have been recorded due to the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), according to the World Health Organization (WHO) COVID-19 Dashboard on September 2021. Apart from the wild-type, other variations have been successfully transmitted early in the outbreak although they were not discovered until March 2020. Modifications in the SARS-CoV-2 genetic material, such as mutation and recombination, have the ability to modify the viral life span, along with transitivity, cellular tropism, as well as symptom severity. Several processes are involved in introducing novel vaccines to the population, includes vaccine manufacturing, preclinical studies, FDA permission or certification, processing, and marketing. COVID-19 vaccine candidates have been developed by a number of public and private groups employing a variety of strategies, such as RNA, DNA, protein, and viral vectored vaccines. This comprehensive review, which included the most subsequent evidence on unique features of SARS-CoV-2 and the associated morbidity and mortality, was carried out using a systematic search of recent online databases in order to generate useful knowledge about the COVID-19 updated versions and their consequences on the disease symptoms and vaccine development.

Bu çalışmada, karbon ve azot atomlarının eşzamanlı difüzyonu temeline dayanan nitrokarbürizasyon sonrası oksidasyon işlemlerinin AISI 4140 çeliğinin mikroyapı, mikrosertlik ve tribolojik özelliklerine etkileri incelenmiştir. Nitrokarbürizasyon işleminin birçok avantajı olmasına rağmen özellikle malzemelerin korozyon ve tribolojik özelliklerini iyileştirilmek için işlem sonrası farklı ısıl işlem tekniklerine ihtiyaç duyulmaktadır. Nitrokarbürizasyon + oksidasyon işlemleri sonucunda malzeme yüzeyinin en dışında yaklaşık 5µm kalınlığında oksit tabakası, hemen altında nitrür ve karbürlerden oluşan yaklaşık 5µm kalınlığında bileşik tabaka ve karbürce zengin difüzyon bölgesi olmak üzere 3 farklı bölge oluşmuştur. Ana fazdan daha sert difüzyon bölgesi, nitrokarbürizasyon ve oksidasyon katmanları sayesinde malzemenin tüm yüzeyinde aşınma davranışları iyileştirilmiştir. Böylece aşınma direnci ile birlikte aynı zamanda sürtünme katsayısı da iyileştirilmiştir.

No abstract

Recurrent pregnancy loss is a phenomenon caused by many etiologies. The majority of these causes are chromosomal anomalies. In this case report, cytogenetic analysis was performed on the family who consulted our department with the complaint of recurrent pregnancy loss. A normal karyotype was found in the female (46, XX); however, t(2;7)(p23;q35) translocation was detected in the male. Reciprocal translocations are a common class of chromosomal abnormalities, and we anticipate this case of translocation will be a new cause for recurrent pregnancy loss. In the analysis, preparations at the level of 500 bands were examined, and at least 20 metaphase areas were evaluated. From the results of cytogenetic and FISH (fluorescence in situ hybridization) analysis, we determined the male had t(2;7)(p23;q35) chromosomal anomaly. The probe binding the patient's 2p23 region signaled at the q-terminal of chromosome 7; however, the other two chromosomes (2 and 7) were normal. There is no report of such a case in the literature for recurrent pregnancy loss complaints. With this case, it will be reported for the first time that an embryo formed with the gametes carrying unbalanced genetic material of an individual with the karyotype 46, XY, t(2;7)(p23;q35) is incompatible with life.

ALMS1 gene, biallelic mutations, obesity, rare diseases Alström syndrome (AS) is a rare autosomal recessive monogenic disorder caused by mutations of the Alström syndrome 1 (ALMS1) gene, located on chromosome 2p13. It is a progressive multisystemic disease characterized mostly by obesity, sensorineural hearing loss, visual impairments, cardiomyopathy, insulin resistance and/or type 2 diabetes mellitus (T2DM), metabolic dysfunctions, non-alcoholic fatty liver disease, and chronic progressive kidney disease. Generally, the first clinical symptoms of the disease appear in the first years of life with a major variation of onset age. In this study, we aimed to examine the molecular diagnosis of a 6-year-old patient with suspected AS clinical symptoms. After applying clinical exome sequencing (CES) in the patient we found a homozygous deletion in exon 8 at the ALMS1 gene (c.2311_2312del). We identified a homozygous frameshift mutation. The reported variant was pathogenic according to the criteria of the American College of Medical Genetics and Genomics (ACMG). Thus, the patient was diagnosed with AS as a result of the combined clinical phenotype and genetic tests results. We hope the variant we found can expand the spectrum of ALMS1 variants in AS.