Defining motility in the Staphylococci

The ability of bacteria to move is critical for their survival in diverse environments and multiple ways have evolved to achieve this. Two forms of motility have recently been described for Staphylococcus aureus, an organism previously considered to be non-motile. One form is called spreading, which is a type of sliding motility and the second form involves comet formation, which has many observable characteristics associated with gliding motility. Darting motility has also been observed in Staphylococcus epidermidis. This review describes how motility is defined and how we distinguish between passive and active motility. We discuss the characteristics of the various forms of Staphylococci motility, the molecular mechanisms involved and the potential future research directions

Cerebral Venous Sinus Thrombosis Following an mRNA COVID-19 Vaccination and Recent Oral Contraceptive Use

Rising concerns of cerebral venous sinus thrombosis (CVST) and other forms of venous thromboembolism have been associated with the SARS-CoV-2 vaccinations. Adverse effects with vector-based vaccines are well documented in the literature, while less is known about the mRNA vaccines. This report documents a case of CVST in a 32-year-old female patient who received her second Pfizer mRNA COVID-19 vaccination 16 days prior to hospital admission and had started oral combined contraceptives approximately 4 months beforehand. Clinicians should be cognizant of the possibility that mRNA vaccines, when combined with other risk factors like oral contraceptive pill use, may enhance one’s hypercoagulable status

Cerebral Venous Sinus Thrombosis Following an mRNA COVID-19 Vaccination and Recent Oral Contraceptive Use

Rising concerns of cerebral venous sinus thrombosis (CVST) and other forms of venous thromboembolism have been associated with the SARS-CoV-2 vaccinations. Adverse effects with vector-based vaccines are well documented in the literature, while less is known about the mRNA vaccines. This report documents a case of CVST in a 32-year-old female patient who received her second Pfizer mRNA COVID-19 vaccination 16 days prior to hospital admission and had started oral combined contraceptives approximately 4 months beforehand. Clinicians should be cognizant of the possibility that mRNA vaccines, when combined with other risk factors like oral contraceptive pill use, may enhance one’s hypercoagulable status

Quorum-sensing signal binding results in dimerization of TraR and its release from membranes into the cytoplasm

Promoter binding by TraR and LuxR, the activators of two bacterial quorum-sensing systems, requires their cognate acyl-homoserine lactone (acyl-HSL) signals, but the role the signal plays in activating these transcription factors is not known. Soluble active TraR, when purified from cells grown with the acyl-HSL, contained bound signal and was solely in dimer form. However, genetic and cross-linking studies showed that TraR is almost exclusively in monomer form in cells grown without signal. Adding signal resulted in dimerization of the protein in a concentration-dependent manner. In the absence of signal, monomer TraR localized to the inner membrane while growth with the acyl-HSL resulted in the appearance of dimer TraR in the cytoplasmic compartment. Affinity chromatography indicated that the N-terminus of TraR from cells grown without signal is hidden. Analysis of heterodimers formed between TraR and its deletion mutants localized the dimerization domain to a region between residues 49 and 156. We conclude that binding signal drives dimerization of TraR and its release from membranes into the cytoplasm

Human breast cancer cell lines as models of growth regulation and disease progression

The routine isolation and culture of human breast cancer cells from patients samples has been a goal of breast cancer cell biologists for over 30 years. Despite extensive work in this area and the development of many human breast cancer cell lines, the proportion of patient samples that give rise to immortalized breast cancer cell lines is still disappointingly low. The majority of human breast cancer cell lines that have been established were isolated many years ago and have been grown continuously under poorly defined culture conditions. These cell lines have been useful for studies of the estrogen receptor biology in human breast cancer cells, in identifying growth factors synthesized by breast cancer cells, and for the characterization of genetic alterations in oncogenes and tumor suppressor genes present in these cells. More recently, tissue culture methods have improved, resulting in the ability to culture routinely normal human mammary epithelial cells of specific lineages and this has resulted in the development of new human breast cancer cell lines. The ability to isolate and culture normal and neoplastic human mammary epithelial cells under similar culture conditions has improved these models dramatically and has resulted in the identification of altered cellular phenotypes of human breast cancer cells.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44963/1/10911_2005_Article_BF02096306.pd