Measuring the impact of maternal critical care admission on short- and longer-term maternal and birth outcomes.

Purpose: Factors increasing the risk of maternal critical illness are rising in prevalence in maternity populations. Studies of general critical care populations highlight that severe illness is associated with longer-term physical and psychological morbidity. We aimed to compare short- and longer-term outcomes between women who required critical care admission during pregnancy/puerperium and those who did not.

The Receiver of the Agrobacterium tumefaciens VirA Histidine Kinase Forms a Stable Interaction with VirG to Activate Virulence Gene Expression.

The plant pathogen Agrobacterium tumefaciens carries a virulence gene system that is required for the initiation of crown gall tumors on susceptible plants. Expression of the vir genes is activated by the VirA/VirG two component regulatory system. VirA is a histidine kinase which signals the presence of certain chemicals found at the site of a plant wound.

Role of the VirA histidine autokinase of Agrobacterium tumefaciens in the initial steps of pathogenesis.

Histidine kinases serve as critical environmental sensing modules, and despite their designation as simple two-component modules, their functional roles are remarkably diverse. In Agrobacterium tumefaciens pathogenesis, VirA serves with VirG as the initiating sensor/transcriptional activator for inter-kingdom gene transfer and transformation of higher plants. Through responses to three separate signal inputs, low pH, sugars, and phenols, A.

The integrity of the periplasmic domain of the VirA sensor kinase is critical for optimal coordination of the virulence signal response in Agrobacterium tumefaciens.

The plant pathogen Agrobacterium tumefaciens responds to three main signals at the plant-bacterium interface: phenolics, such as acetosyringone (AS), monosaccharides, and acidic pH (∼5.5). These signals are transduced via the chromosomally encoded sugar binding protein ChvE and the Ti plasmid-encoded VirA/VirG two-component regulatory system, resulting in the transcriptional activation of the Ti plasmid virulence genes.

Challenges of major obstetric haemorrhage.

Every minute of every day, a woman dies in pregnancy or childbirth. The biggest killer is obstetric haemorrhage, the successful treatment of which is a challenge for both the developed and developing worlds. The presence of an attendant at every birth and access to emergency obstetric care are key to reducing maternal morbidity and mortality in the developing world while resource-rich countries have a rising caesarean section rate with its consequential effect on the incidence of abnormal placentation and its link with peripartum hysterectomy.

The receiver domain of hybrid histidine kinase VirA: an enhancing factor for vir gene expression in Agrobacterium tumefaciens.

The plant pathogen Agrobacterium tumefaciens expresses virulence (vir) genes in response to chemical signals found at the site of a plant wound. VirA, a hybrid histidine kinase, and its cognate response regulator, VirG, regulate vir gene expression. The receiver domain at the carboxyl end of VirA has been described as an inhibitory element because its removal increased vir gene expression relative to that of full-length VirA.

Strategies to manage major obstetric haemorrhage.

Purpose Of Review: Haemorrhage remains a cause of significant maternal morbidity and mortality. This review summarizes the prevention, management and treatment of obstetric haemorrhage and highlights recent advances and developments.

Recent Findings: Postpartum haemorrhage is the most common cause of major obstetric haemorrhage and is usually due to uterine atony.

The plant signal salicylic acid shuts down expression of the vir regulon and activates quormone-quenching genes in Agrobacterium.

Agrobacterium tumefaciens is capable of transferring and integrating an oncogenic T-DNA (transferred DNA) from its tumor-inducing (Ti) plasmid into dicotyledonous plants. This transfer requires that the virulence genes (vir regulon) be induced by plant signals such as acetosyringone in an acidic environment. Salicylic acid (SA) is a key signal molecule in regulating plant defense against pathogens.

Nucleic acid extraction from Agrobacterium strains.

Agrobacterium is routinely used as a tool for moving genetic constructs into plant cells. The successful use of Agrobacterium as a tool for the genetic engineering of plant cells often requires the manipulation and analysis of nucleic acids present in recombinant Agrobacterium strains. Here we present dependable methods for the isolation of genomic (total) DNA, mega-plasmid DNA, shuttle or binary plasmid DNA, and RNA.

Three methods for the introduction of foreign DNA into Agrobacterium.

The genetic manipulation of Agrobacterium tumefaciens is used to facilitate studies of bacterial gene functions or as a first step in introducing genetic material into transformable plant cells through the use of T-DNA binary vectors. Three methods are commonly used. Transformation with purified plasmid can be done with either electroporation or a simple freeze/thaw transformation method.

Culture and maintenance of Agrobacterium strains.

As aerobic chemoorganotrophs, most Agrobacterium strains will grow on a wide range of complex and defined media. Methods commonly used for the culture and storage of other chemoorganotrophs will usually work for agrobacteria as well. Problems with culture or strain maintenance will occur more frequently because of careless technique than because of strain difficulties.

Intersubunit complementation of sugar signal transduction in VirA heterodimers and posttranslational regulation of VirA activity in Agrobacterium tumefaciens.

The VirA/VirG two-component regulatory system of Agrobacterium tumefaciens regulates expression of the virulence (vir) genes that control the infection process leading to crown gall tumor disease on susceptible plants. VirA, a membrane-bound homodimer, initiates vir gene induction by communicating the presence of molecular signals found at the site of a plant wound through phosphorylation of VirG. Inducing signals include phenols, monosaccharides, and acidic pH.