Human chondrocytes differentially express matrix modulators during in vitro expansion for tissue engineering

Cartilage tissue engineering plays an important role in the generation of grafts for reconstructive surgery. In cultured chondrocytes, the dedifferentiation of cells seems unavoidable for multiplication. Dedifferentiated cells produce matrix of less quality, and the molecular basis is still not well understood. Therefore, the aim of our study was to investigate the expression of matrix modulators in human chondrocytes during expansion. Human chondrocytes were isolated from septal cartilage (n=32) and held in primary cell culture. Cells were harvested after 1, 6 and 21 days. The differentiation of cells using light microscopy, the expression patterns of various proteins (MMPs, BMPs, and TIMPs) using immunohistochemistry, and the expression of distinct genes using microarray technique, were investigated. The chondrocytes showed strong in vitro proliferation. After 6 and 21 days, BMP-5 and -8 were up-regulated, BMP-2 was down-regulated and BMP-6 was inactivated. Other BMPs were not expressed. The expression of MMP-2, -3 and -13 was up-regulated from day 1 to 21, and MMP-12 and -20 were down-regulated. Other MMPs were not expressed. TIMP-1 was up-regulated and TIMP-3 was down-regulated during expansion. Differential expression of matrix modulators might influence the matrix composition of engineered cartilage. Improving the basic knowledge in this area may ultimately help clinicians to identify and proactively intervene in an attempt to prevent bioartificial cartilage from losing stability.     

A novel de novo heterozygous pathogenic variant in the SDHA gene results in childhood onset bilateral optic atrophy and cognitive impairment

Metabolic Brain Disease - Isolated defects in the mitochondrial respiratory chain complex II (CII; succinate-ubiquinone oxidoreductase) are extremely rare and mainly result from bi-allelic...     

Risk factors for hospital admission among COVID-19 patients with diabetes: A study from Saudi Arabia

Objectives:To elucidate the risk factors for hospital admission among COVID-19 patients with type 2 diabetes mellitus (T2DM).Methods:This retrospective study was conducted at the Prince Sultan Military Medical City, Riyadh, Saudi Arabia between May 2020 and July 2020. Out of 7,260 COVID-19 patients, 920 were identified as T2DM. After the exclusion process, 806 patients with T2DM were included in this analysis. Patients’ data were extracted from electronic medical records. A logistic regression model was performed to estimate the risk factors of hospital admission.Results:Of the total of 806 COVID-19 patients with T2DM, 48% were admitted in the hospital, 52% were placed under home isolation. Older age between 70-79 years (OR [odd ratio] 2.56; p=0.017), ≥80 years (OR 6.48; p=0.001) were significantly more likely to be hospitalized compared to <40 years. Similarly, patients with higher HbA1c level of ≥9% compared to <7%; (OR 1.58; p=0.047); patients with comorbidities such as, hypertension (OR 1.43; p=0.048), cardiovascular disease (OR 1.56; p=0.033), cerebrovascular disease (OR 2.38; p=0.016), chronic pulmonary disease (OR 1.51; p=0.018), malignancy (OR 2.45; p=0.025), chronic kidney disease (CKD) IIIa, IIIb, IV (OR 2.37; p=0.008), CKD V (OR 5.07; p=0.007) were significantly more likely to be hospitalized. Likewise, insulin-treated (OR 1.46; p=0.03) were more likely to require hospital admission compared to non-insulin treated patients.Conclusion:Among COVID-19 patients with diabetes, higher age, high HbA1c level, and presence of other comorbidities were found to be significant risk factors for the hospital admission.     

A comparative study of the secretory IgA immunoglobulins (s.IgA) in mothers and children with SECC versus a caries free group children and their mothers

Early childhood caries (ECC) is recognized as an infectious disease. The first step in its development is primary infection by the bacterium S. mutans which has been identified as the primary etiologic factors in dental caries. Lactobacilli were also found to play a role in the progression of disease. However the underlying mechanism of immune response to caries is unclear. The association between secretory IgA (s.IgA) and cariogenic microorganisms is still controversial. The purpose of this study was to assess the level of salivary IgA in caries free children, and children with SECC and their corresponding mothers. The study also aims at correlating the children's levels to their mothers'. Sixty children and their mothers attending the dental clinic in King Abdulaziz University participated in our study. Their age ranged from 3 - 5 years. The study groups consisted of thirty children with SECC and a control group consisting of thirty caries free children. Children together with their mothers were examined and their caries level was recorded. Stimulated saliva was collected from each participant for immunological assessment. The secretory IgA (s. IgA) level was assessed by ELISA test. Our study has shown that children with SECC and their mothers had higher levels of s. IgA than the caries free children and their mothers. A positive high correlation was found between secretory IgA of mothers and children in both groups.     

Synthesis,SAR studies,and insecticidal activities of certain N-heterocycles derived from 3-((2-chloroquinolin-3-yl)methylene)-5-phenylfuran-2(3H)-one against Culex pipiens L. larvae

An acid hydrazide derivative was synthesized and transformed into a variety of valuable N-heterocycles such as pyridazinone, oxadiazole, triazolopyridazinone, and triazole derivatives via reactions with certain carbon electrophiles such as 4-methoxybenzaldehyde, indole-3-carbaldehyde, pentan-2,4-dione, and carbon disulfide. The chemical structures of all prepared compounds were verified via their analytical and spectroscopic data. The insecticidal activity of the N-heterocycles was evaluated against field and lab strains of the third larval instar of Culex pipiens. All tested compounds exhibited higher larvicidal activity against the lab strains compared to the field strains, with dissimilar ratios. The obtained results demonstrate that the high toxicity achieved by oxadiazole followed the order of furanone, pyridazinone and hydrazide, with lower LC₅₀ values of the hydrazone and N-acetylpyridazinone derivatives compared to that of imidacloprid. Interestingly, these compounds are promising agents for insect pest control, especially since they are insoluble in water and can overcome the disadvantages of neonicotinoid applications in pest management programs.

A new series of N-heterocycles including pyridazinone, oxadiazole, triazolopyridazinone, and triazole derivatives were synthesized from the acid hydrazide via its reaction with certain carbon electrophiles.