Head CT for the intensivist: 10 tips and pearls.

Head imaging is an essential diagnostic tool for the management of patients with most acute neurological emergencies involving the brain. While numerous modalities including magnetic resonance imaging and catheter angiography play a role, computed tomography (CT) of the brain is far and away the most widely utilized technique because of its widespread availability and the fact that it is usually easier to implement in critically ill and potentially unstable patients. CT is particularly useful in identifying acute intracranial hemorrhage and this makes it often indispensable in the management of patients with traumatic brain injury and hemorrhagic stroke. However, shortcomings in identifying early ischemia on non-contrast CT mean that care must be taken in considering findings early after symptom onset, with newer CT sequences such as CT angiography and CT perfusion adding value. The critical role played by intensivists in managing neurocritical care patients necessitates familiarity and ability with viewing and understanding the advantages and shortcomings of head CT imaging and under which circumstances other modalities may be appropriate to obtain. This manuscript provides ten different circumstances commonly encountered in neurocritical care and how intensivists can use CT for the benefit of their patients.

Colistin resistance due to insertional inactivation of the mgrB in Klebsiella pneumoniae of clinical origin: First report from India.

OBJECTIVE: Mutations in mgrB, phoP/phoQ, pmrA, pmrB, pmrC, and crrABC regulatory systems have been found responsible for colistin resistance. The aim of our study was to investigate the role of alteration in mgrB gene and plasmid mediate mcr-1 and mcr-2 genes as a source of colistin resistance in 17 non duplicate Klebsiella pneumoniae clinical isolates. METHODS: All isolates classified as resistant to colistin by VITEK 2 system (BioMerieux, Marcy I' Etoile, France) were included. Susceptibility to colistin was also determined by broth microdilution using breakpoints recommended by EUCAST (>2mg/L resistant; and ≤2mg/L susceptible). PCR amplification of mgrB gene was performed and sequenced using specific primers. Presence of mcr-1 and mcr-2 was also investigated using PCR. RESULTS: PCR amplification of the mgrB gene of the 17 K.pneumoniae isolates revealed a larger (~1000bp) amplicon in three isolates when compared with the wild type mgrB ampiclon (250 bp). Sequencing of these amplicons showed that mgrB was disrupted by the insertion of ISKpn14, a IS element belonging to the IS1 family. Sequencing, of the 250 bp mgrB gene in the remaining 14 isolates revealed frame shift mutation after the second codon leading to a premature stop codon in only one isolate. CONCLUSIONS: The study showed that colistin resistance in 20% of the K. pneumoniae isolates was due to loss of function of mgrB. We describe for the first-time from India, insertional inactivation of mgrB by ISKpn14 inserted at different sites, responsible for colistin resistance.

Applying GIS and high performance agent-based simulation for managing an Old World Screwworm fly invasion of Australia.

Agent-based modelling has proven to be a promising approach for developing rich simulations for complex phenomena that provide decision support functions across a broad range of areas including biological, social and agricultural sciences. This paper demonstrates how high performance computing technologies, namely General-Purpose Computing on Graphics Processing Units (GPGPU), and commercial Geographic Information Systems (GIS) can be applied to develop a national scale, agent-based simulation of an incursion of Old World Screwworm fly (OWS fly) into the Australian mainland. The development of this simulation model leverages the combination of massively data-parallel processing capabilities supported by NVidia's Compute Unified Device Architecture (CUDA) and the advanced spatial visualisation capabilities of GIS. These technologies have enabled the implementation of an individual-based, stochastic lifecycle and dispersal algorithm for the OWS fly invasion. The simulation model draws upon a wide range of biological data as input to stochastically determine the reproduction and survival of the OWS fly through the different stages of its lifecycle and dispersal of gravid females. Through this model, a highly efficient computational platform has been developed for studying the effectiveness of control and mitigation strategies and their associated economic impact on livestock industries can be materialised.

Utility of the Malayalam translation of the 7- minute screen for Alzheimer's disease risk in an Indian community.

BACKGROUND: Alzheimer's disease (AD) is suspected to be currently under-diagnosed in India, thus the need for a brief, effective screening test for the condition. AIMS: We aimed to test the Malayalam translation of the 7-Minute Screen (7MS) for detecting those at high risk for AD and to report on the subscores used to derive the Alzheimer's risk score. SETTING AND DESIGN: This study was performed in Kerala State amongst young university students and elders in residential care homes. MATERIALS AND METHODS: Two hundred and eighty-two volunteers were tested, 178 young controls (aged 20-29) and 104 literate elders, (55-92 years). None were clinically diagnosed with AD. STATISTICAL ANALYSES: Elders and controls were assessed as High or Low AD Risk with the published 7MS algorithm. Performance was compared between groups with ANOVA. RESULTS: The algorithm estimated high (n=61/104) or low (n=40/104) AD risk in the elderly. Significant differences were found between controls, low- and high-risk groups on all four components of the screen (Orientation: F=131.1, Enhanced Cued Recall: F=23.4, Clock Drawing: F=65.1, Verbal Fluency: F=15.7, P<0.0001 for all) and in the risk scores (F=144.7, P<0.0001). Age and gender affected verbal fluency, orientation and clock drawing performance. The high-risk group had worse scores for orientation and better scores for memory than previously reported for AD cases in other populations. CONCLUSIONS: The 7MS may be a useful screening test for cognitive impairment in India. Suggestions are given for revising the 'risk algorithm' for more appropriate AD risk assessment in this population.