Randomized pharmacokinetic and pharmacodynamic comparison of fluoroquinolones for tuberculous meningitis.

Tuberculous meningitis (TBM) is the most lethal form of tuberculosis, and new treatments that improve outcomes are required. We randomly assigned adults with TBM to treatment with standard antituberculosis treatment alone or in combination with ciprofloxacin (750 mg/12 h), levofloxacin (500 mg/12 h), or gatifloxacin (400 mg/24 h) for the first 60 days of therapy. Fluoroquinolone concentrations were measured with plasma and cerebrospinal fluid (CSF) specimens taken at predetermined, randomly assigned times throughout treatment. We aimed to describe the pharmacokinetics of each fluoroquinolone during TBM treatment and evaluate the relationship between drug exposure and clinical response over 270 days of therapy (Controlled Trials number ISRCTN07062956). Sixty-one patients with TBM were randomly assigned to treatment with no fluoroquinolone (n = 15), ciprofloxacin (n = 16), levofloxacin (n = 15), or gatifloxacin (n = 15). Cerebrospinal fluid penetration, measured by the ratio of the plasma area under the concentration-time curve from 0 to 24 h (AUC0–24) to the cerebrospinal fluid AUC0–24, was greater for levofloxacin (median, 0.74; range, 0.58 to 1.03) than for gatifloxacin (median, 0.48; range, 0.47 to 0.50) or ciprofloxacin (median, 0.26; range, 0.11 to 0.77). Univariable and multivariable analyses of fluoroquinolone exposure against a range of different treatment responses revealed worse outcomes among patients with lower and higher plasma and CSF exposures than for patients with intermediate exposures (a U-shaped exposure-response). TBM patients most likely to benefit from fluoroquinolone therapy were identified, along with exposure-response relationships associated with improved outcomes. Fluoroquinolones add antituberculosis activity to the standard treatment regimen, but to improve outcomes of TBM, they must be started early, before the onset of coma

Prolonged Survival in a Patient with Neuroendocrine Tumor of the Cecum and Diffuse Peritoneal Carcinomatosis

Peritoneal carcinomatosis is a well-known factor of poor prognosis in patients with digestive adenocarcinomas. Peritoneal dissemination may also occur in midgut well-differentiated neuroendocrine tumors, but its influence on survival is ill-defined. We report here the history of a 64-year-old woman who had a neuroendocrine tumor of the cecum with multiple synchronous metastases in the liver and diffuse peritoneal carcinomatosis. She underwent surgical resection of the primary tumor and cytoreduction of liver metastases, and received subsequently chemotherapy and somatostatin analogs. In spite of the widespread extension of the disease, she survived for 13 years and died from a carcinoid heart disease. We discuss the natural history and prognostic factors in patients with midgut well-differentiated neuroendocrine tumors, with a focus on the impact of the peritoneal carcinomatosis

Reversibility of liver fibrosis

Liver fibrosis, and its end stage cirrhosis are a major cause of morbidity and mortality and therapeutic options are limited. However, the traditional view of liver disease as an irreversible process is obsolete and it is now evident that the development of liver fibrosis is a dynamic and potentially bidirectional process. Spontaneous resolution of scarring is seen in animal models of liver fibrosis and in human trials in which the stimuli responsible for chronic or repeated hepatic inflammation is successfully removed. Key players in the process are hepatic stellate cells, macrophages, MMPs and their inhibitors Timps. It is also evident that in advanced fibrotic liver disease, specific histological features define what is currently described as "irreversible" fibrosis. This includes the development of paucicellular scars enriched in extensively cross-linked matrix components, such as fibrillar collagen and elastin. Our recent work has focused on the role of macrophage metalloelastase (MMP-12) in the turnover of elastin in reversible and irreversible models of fibrosis. We have shown that elastin turnover in liver injury and fibrosis is regulated by macrophages via Mmp-12 expression, activity and ratio to its inhibitor Timp-1. Failure of elastin degradation, together with increased deposition leads to accumulation of elastin in the fibrotic scars

Transient Receptor Potential Ion Channels Control Thermoregulatory Behaviour in Reptiles

Biological functions are governed by thermodynamics, and animals regulate their body temperature to optimise cellular performance and to avoid harmful extremes. The capacity to sense environmental and internal temperatures is a prerequisite for the evolution of thermoregulation. However, the mechanisms that enable ectothermic vertebrates to sense heat remain unknown. The recently discovered thermal characteristics of transient receptor potential ion channels (TRP) render these proteins suitable to act as temperature sensors. Here we test the hypothesis that TRPs are present in reptiles and function to control thermoregulatory behaviour. We show that the hot-sensing TRPV1 is expressed in a crocodile (Crocodylus porosus), an agamid (Amphibolurus muricatus) and a scincid (Pseudemoia entrecasteauxii) lizard, as well as in the quail and zebrafinch (Coturnix chinensis and Poephila guttata). The TRPV1 genes from all reptiles form a unique clade that is delineated from the mammalian and the ancestral Xenopus sequences by an insertion of two amino acids. TRPV1 and the cool-sensing TRPM8 are expressed in liver, muscle (transversospinalis complex), and heart tissues of the crocodile, and have the potential to act as internal thermometer and as external temperatures sensors. Inhibition of TRPV1 and TRPM8 in C. porosus abolishes the typically reptilian shuttling behaviour between cooling and heating environments, and leads to significantly altered body temperature patterns. Our results provide the proximate mechanism of thermal selection in terrestrial ectotherms, which heralds a fundamental change in interpretation, because TRPs provide the mechanism for a tissue-specific input into the animals' thermoregulatory response

The Terminal Immunoglobulin-Like Repeats of LigA and LigB of Leptospira Enhance Their Binding to Gelatin Binding Domain of Fibronectin and Host Cells

Leptospira spp. are pathogenic spirochetes that cause the zoonotic disease leptospirosis. Leptospiral immunoglobulin (Ig)-like protein B (LigB) contributes to the binding of Leptospira to extracellular matrix proteins such as fibronectin, fibrinogen, laminin, elastin, tropoelastin and collagen. A high-affinity Fn-binding region of LigB has been localized to LigBCen2, which contains the partial 11th and full 12th Ig-like repeats (LigBCen2R) and 47 amino acids of the non-repeat region (LigBCen2NR) of LigB. In this study, the gelatin binding domain of fibronectin was shown to interact with LigBCen2R (KD = 1.91±0.40 µM). Not only LigBCen2R but also other Ig-like domains of Lig proteins including LigAVar7'-8, LigAVar10, LigAVar11, LigAVar12, LigAVar13, LigBCen7'-8, and LigBCen9 bind to GBD. Interestingly, a large gain in affinity was achieved through an avidity effect, with the terminal domains, 13th (LigA) or 12th (LigB) Ig-like repeat of Lig protein (LigAVar7'-13 and LigBCen7'-12) enhancing binding affinity approximately 51 and 28 fold, respectively, compared to recombinant proteins without this terminal repeat. In addition, the inhibited effect on MDCKs cells can also be promoted by Lig proteins with terminal domains, but these two domains are not required for gelatin binding domain binding and cell adhesion. Interestingly, Lig proteins with the terminal domains could form compact structures with a round shape mediated by multidomain interaction. This is the first report about the interaction of gelatin binding domain of Fn and Lig proteins and provides an example of Lig-gelatin binding domain binding mediating bacterial-host interaction

On the Role of the Striatum in Response Inhibition

BACKGROUND: Stopping a manual response requires suppression of the primary motor cortex (M1) and has been linked to activation of the striatum. Here, we test three hypotheses regarding the role of the striatum in stopping: striatum activation during successful stopping may reflect suppression of M1, anticipation of a stop-signal occurring, or a slower response build-up. METHODOLOGY/PRINCIPAL FINDINGS: Twenty-four healthy volunteers underwent functional magnetic resonance imaging (fMRI) while performing a stop-signal paradigm, in which anticipation of stopping was manipulated using a visual cue indicating stop-signal probability, with their right hand. We observed activation of the striatum and deactivation of left M1 during successful versus unsuccessful stopping. In addition, striatum activation was proportional to the degree of left M1 deactivation during successful stopping, implicating the striatum in response suppression. Furthermore, striatum activation increased as a function of stop-signal probability and was to linked to activation in the supplementary motor complex (SMC) and right inferior frontal cortex (rIFC) during successful stopping, suggesting a role in anticipation of stopping. Finally, trial-to-trial variations in response time did not affect striatum activation. CONCLUSIONS/SIGNIFICANCE: The results identify the striatum as a critical node in the neural network associated with stopping motor responses. As striatum activation was related to both suppression of M1 and anticipation of a stop-signal occurring, these findings suggest that the striatum is involved in proactive inhibitory control over M1, most likely in interaction with SMC and rIFC

A proteomic approach to investigating gene cluster expression and secondary metabolite functionality in Aspergillus fumigatus.

A combined proteomics and metabolomics approach was utilised to advance the identification and characterisation of secondary metabolites in Aspergillus fumigatus. Here, implementation of a shotgun proteomic strategy led to the identification of non-redundant mycelial proteins (n = 414) from A. fumigatus including proteins typically under-represented in 2-D proteome maps: proteins with multiple transmembrane regions, hydrophobic proteins and proteins with extremes of molecular mass and pI. Indirect identification of secondary metabolite cluster expression was also achieved, with proteins (n = 18) from LaeA-regulated clusters detected, including GliT encoded within the gliotoxin biosynthetic cluster. Biochemical analysis then revealed that gliotoxin significantly attenuates H2O2-induced oxidative stress in A. fumigatus (p>0.0001), confirming observations from proteomics data. A complementary 2-D/LC-MS/MS approach further elucidated significantly increased abundance (p<0.05) of proliferating cell nuclear antigen (PCNA), NADH-quinone oxidoreductase and the gliotoxin oxidoreductase GliT, along with significantly attenuated abundance (p<0.05) of a heat shock protein, an oxidative stress protein and an autolysis-associated chitinase, when gliotoxin and H2O2 were present, compared to H2O2 alone. Moreover, gliotoxin exposure significantly reduced the abundance of selected proteins (p<0.05) involved in de novo purine biosynthesis. Significantly elevated abundance (p<0.05) of a key enzyme, xanthine-guanine phosphoribosyl transferase Xpt1, utilised in purine salvage, was observed in the presence of H2O2 and gliotoxin. This work provides new insights into the A. fumigatus proteome and experimental strategies, plus mechanistic data pertaining to gliotoxin functionality in the organism

Current trends in cannulation and neuroprotection during surgery of the aortic arch in Europe†‡

OBJECTIVES To conduct a survey across European cardiac centres to evaluate the methods used for cerebral protection during aortic surgery involving the aortic arch. METHODS All European centres were contacted and surgeons were requested to fill out a short, comprehensive questionnaire on an internet-based platform. One-third of more than 400 contacted centres completed the survey correctly. RESULTS The most preferred site for arterial cannulation is the subclavian-axillary, both in acute and chronic presentation. The femoral artery is still frequently used in the acute condition, while the ascending aorta is a frequent second choice in the case of chronic presentation. Bilateral antegrade brain perfusion is chosen by the majority of centres (2/3 of cases), while retrograde perfusion or circulatory arrest is very seldom used and almost exclusively in acute clinical presentation. The same pumping system of the cardio pulmonary bypass is most of the time used for selective cerebral perfusion, and the perfusate temperature is usually maintained between 22 and 26°C. One-third of the centres use lower temperatures. Perfusate flow and pressure are fairly consistent among centres in the range of 10-15 ml/kg and 60 mmHg, respectively. In 60% of cases, barbiturates are added for cerebral protection, while visceral perfusion still receives little attention. Regarding cerebral monitoring, there is a general tendency to use near-infrared spectroscopy associated with bilateral radial pressure measurement. CONCLUSIONS These data represent a snapshot of the strategies used for cerebral protection during major aortic surgery in current practice, and may serve as a reference for standardization and refinement of different approache

Study protocol: a multi-centre randomised study of induction chemotherapy followed by capecitabine +/- nelfinavir with high- or standard-dose radiotherapy for locally advanced pancreatic cancer (SCALOP-2)

Background Induction chemotherapy followed by chemoradiation is a treatment option for patients with locally advanced pancreatic cancer (LAPC). However, overall survival is comparable to chemotherapy alone and local progression occurs in nearly half of all patients, suggesting chemoradiation strategies should be optimised. SCALOP-2 is a randomised phase II trial testing the role of radiotherapy dose escalation and/or the addition of the radiosensitiser nelfinavir, following induction chemotherapy of gemcitabine and nab-paclitaxel (GEMABX). A safety run-in phase (stage 1) established the nelfinavir dose to administer with chemoradiation in the randomised phase (stage 2). Methods Patients with locally advanced, inoperable, non-metastatic pancreatic adenocarcinoma receive three cycles of induction GEMABX chemotherapy prior to radiological assessment. Those with stable/responding disease are eligible for further trial treatment. In Stage 1, participants received one further cycle of GEMABX followed by capecitabine-chemoradiation with escalating doses of nelfinavir in a rolling-six design. Stage 2 aims to register 262 and randomise 170 patients with responding/stable disease to one of five arms: capecitabine with high- (arms C + D) or standard-dose (arms A + B) radiotherapy with (arms A + C) or without (arms B + D) nelfinavir, or three more cycles of GEMABX (arm E). Participants allocated to the chemoradiation arms receive another cycle of GEMABX before chemoradiation begins. Co-primary outcomes are 12-month overall survival (radiotherapy dose-escalation question) and progression-free survival (nelfinavir question). Secondary outcomes include toxicity, quality of life, disease response rate, resection rate, treatment compliance, and CA19–9 response. SCALOP-2 incorporates a detailed radiotherapy quality assurance programme. Discussion SCALOP-2 aims to optimise chemoradiation in LAPC and incorporates a modern induction regimen