Molecular characterization of Ehrlichia canis from naturally infected dogs reveals a novel Asiatic-lineage and co-circulation of multiple lineages in India.

Canine monocytic ehrlichiosis caused by Ehrlichia canis is an important rickettsial pathogen of dogs transmitted by Rhipicephalus sanguineus sensu lato ticks in India. Globally, molecular characterization of E. canis is done using different E. canis gene targets. This study aimed to characterize genetic diversity of uncultured Ehrlichia species from dogs by 16S rRNA and partial gp200 gene (termed as p43 region) sequences data. Phylogeny based on 16S rRNA gene did not reveal any region-specific lineages. The phylogeny based on 5' region of E. canis gp200 gene (termed as p43 region) revealed four major clusters (A, B, C and D) and the Indian isolates fall under clusters A and B. Cluster A is characterized by an insertion of unique 141 bp tandem repeat sequence. Similar tandem repeat sequence was found in one of the E canis isolates from east-Asia, suggesting a possible divergence within this species. The study shows evidence for divergence of a new lineage within E. canis. The location of this insertion at the 'ankyrin repeat domains' containing region is suggestive of its possible role in modulation of host responses.

The human discs large protein 1 interacts with and maintains connexin 43 at the plasma membrane in keratinocytes.

Gap junction channels, composed of connexins, allow direct cell-to-cell communication. Connexin 43 (Cx43; also known as GJA1) is widely expressed in tissues, including the epidermis. In a previous study of human papillomavirus-positive cervical epithelial tumour cells, we identified Cx43 as a binding partner of the human homologue of Drosophila Discs large (Dlg1; also known as SAP97). Dlg1 is a member of the membrane associated-guanylate kinase (MAGUK) scaffolding protein family, which is known to control cell shape and polarity. Here, we show that Cx43 also interacts with Dlg1 in uninfected keratinocytes in vitro and in keratinocytes, dermal cells and adipocytes in normal human epidermis in vivo. Depletion of Dlg1 in keratinocytes did not alter Cx43 transcription but was associated with a reduction in Cx43 protein levels. Reduced Dlg1 levels in keratinocytes resulted in a reduction in Cx43 at the plasma membrane with a concomitant reduction in gap junctional intercellular communication and relocation of Cx43 to the Golgi compartment. Our data suggest a key role for Dlg1 in maintaining Cx43 at the plasma membrane in keratinocytes.

Formulation of essential oil-loaded chitosan-alginate nanocapsules.

Naturally occurring polymers such as alginate (AL) and chitosan (CS) are widely used in biomedical and pharmaceutical fields in various forms such as nanoparticles, capsules, and emulsions. These polymers have attractive applications in drug delivery because of their biodegradability, biocompatibility, and nontoxic nature. The pharmaceutical applications of essential oils such as turmeric oil and lemongrass oil are well-known, and their active components, ar-turmerone and citral, respectively, are known for their antibacterial, antifungal, antioxidant, antimutagenic, and anticarcinogenic properties. However, these essential oils are unstable, volatile, and insoluble in water, which limits their use for new formulations. Therefore, this study focuses on developing a CS-AL nanocarrier for the encapsulation of essential oils. The effects of process parameters such as the effect of heat and the concentrations of AL and CS were investigated. Various physicochemical characterization techniques such as scanning electron microscopy, Fourier transform infrared spectroscopy, and ultraviolet-visible spectroscopy were performed. Results of characterization studies showed that 0.3 mg/mL AL and 0.6 mg/mL CS produced minimum-sized particles (<300 nm) with good stability. It was also confirmed that the oil-loaded nanocapsules were hemocompatible, suggesting their use for future biomedical and pharmaceutical applications. Furthermore, the antiproliferative activity of turmeric oil- and lemongrass oil-loaded nanocapsules was estimated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay in A549 cell lines and it was found that both the nanoformulations had significant antiproliferative properties than the bare oil.

Branch retinal artery occlusion and non-ischemic central retinal vein occlusion due to hyperhomocysteinemia in a 14-year-old child.

A 14-year-old girl presented with sudden, painless loss of vision in the left eye. Complete ophthalmologic examination including fluorescein angiography revealed an impending central vein occlusion and a branch retinal artery occlusion inferotemporally. One month later, there was a non-ischemic central retinal vein occlusion of the same eye. Systemic evaluation led to the diagnosis of hyperhomocysteinemia. This case report underscores the importance of excluding hyperhomocysteinemia in vascular occlusive disease.