Antimicrobial Resistance (AMR) and Multidrug Resistance (MDR): Overview of Current Approaches, Consortia and Intellectual Property Issues

The supply of new diagnostics and treatments is insufficient to keep up with the increase in antimicrobial resistance (AMR) and multidrug resistance (MDR) as older medicines are used more widely and microbes develop resistance to them. At the same time, significant quantities of antibiotics are used on patients and animals that do not need them, while others who do need them lack access. Effective responses to AMR/MDR require effort by both the public and private sectors to develop and disseminate new diagnostics, vaccines and treatments on a global scale, as well as to adapt them to local needs. This calls for good governance to identify priorities, raise awareness and ensure effective stewardship at global, regional and national levels to minimize the development of resistance. Failure to act appropriately in one country will adversely impact all countries as resistance travels fast. Based on a review of recent literature, this WIPO Global Challenges Report includes a broad overview of current approaches and consortia designed to meet the challenge of research and development (R&D) investment for new treatments. It also examines patent applications by both the public and the private sectors as an indicator of innovative activity. This report finds that there is a need to address the unique market challenges and specific uncertainties associated with the development of new diagnostics and treatments, where current approaches are not optimal. An effective global framework that achieves the necessary political support while ensuring effective local implementation is crucial. There is an opportunity to complement this work by formulating mechanisms that drive innovation for results to incentivize success, while feeding expertise and experience into stewardship and access efforts. Intellectual property (IP) could be used in a constructive manner as one element in any reward or prize system for AMR/MDR R&D – both in terms of providing an incentive and governance

Altered muscarinic and nicotinic receptor densities in cortical and subcortical brain regions in Parkinson's disease

Muscarinic and nicotinic cholinergic receptors and choline acetyltransferase activity were studied in postmortem brain tissue from patients with histopathologically confirmed Parkinson's disease and matched control subjects. Using washed membrane homogenates from the frontal cortex, hippocampus, caudate nucleus, and putamen, saturation analysis of specific receptor binding was performed for the total number of muscarinic receptors with [3H]quinuclidinyl benzilate, for muscarinic M1 receptors with [3H]pirenzepine, for muscarinic M2 receptors with [3H]oxotremorine-M, and for nicotinic receptors with (-)-[3H]nicotine. In comparison with control tissues, choline acetyl-transferase activity was reduced in the frontal cortex and hippocampus and unchanged in the caudate nucleus and putamen of parkinsonian patients. In Parkinson's disease the maximal binding site density for [3H]quinuclidinyl benzilate was increased in the frontal cortex and unaltered in the hippocampus, caudate nucleus, and putamen. Specific [3H]pirenzepine binding was increased in the frontal cortex, unaltered in the hippocampus, and decreased in the caudate nucleus and putamen. In parkinsonian patients Bmax values for specific [3H]oxotremorine-M binding were reduced in the cortex and unchanged in the hippocampus and striatum compared with controls. Maximal (-)-[3H]nicotine binding was reduced in both the cortex and hippocampus and unaltered in both the caudate nucleus and putamen. Alterations of the equilibrium dissociation constant were not observed for any ligand in any of the brain areas examined. The present results suggest that both the innominatocortical and the septohippocampal cholinergic systems degenerate in Parkinson's disease.(ABSTRACT TRUNCATED AT 250 WORDS

Terguride stimulates locomotor activity at 2 months but not 10 months after 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine treatment of common marmosets

The mixed dopamine (DA) agonist/antagonist terguride acts as a DA antagonist on normosensitive receptors but shows DA agonistic properties at supersensitive DA receptors. Such a compound could offer an alternative to the treatment of Parkinson's disease with indirect or direct DA agonists. The present study compares the actions of terguride, 4-12 mg/kg i.p., in naive common marmosets with its effects in animals rendered parkinsonian by administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), 2 months or 10 months previously, in order to test its antiparkinsonian efficacy. Terguride reduced locomotor activity in naive common marmosets, similar to its effects in rodents and in line with the DA antagonistic activity of the compound. In marmosets treated with MPTP 2 months previously and exhibiting pronounced behavioural motor deficits, terguride stimulated locomotor activity, showing DA agonistic properties under these conditions. In contrast, the locomotor activity of animals that had recovered from MPTP treatment 10 months previously was not altered by terguride. It is concluded that terguride has anti-akinetic efficacy in this primate model of Parkinson's disease. In addition, terguride offers a unique opportunity to differentiate, pharmacologically, the extent of dopaminergic recovery from MPTP treatment in this primate species

Brain muscarinic cholinergic receptors in Huntington's disease

Muscarinic cholinergic receptors and choline acetyltransferase (ChAT) activity were studied in postmortem brain tissue from patients with Huntington's disease and matched control subjects. In comparison with controls, reductions in ChAT activity were found in the hippocampus, but not in the temporal cortex in Huntington's disease. Patients with Huntington's disease showed reduced densities of the total number of muscarinic receptors and of M-2 receptors in the hippocampus while the density of M-1 receptors was unaltered. Muscarinic receptor binding was unchanged in the temporal cortex. These results indicate a degeneration in Huntington's disease of the septo-hippocampal cholinergic pathway, but no impairment of the innominato-cortical cholinergic system

Trophodynamics of krill and its potential role in blue whale feeding in the Perth Canyon, south-east Indian Ocean

Migrating blue whales along the Western Australian coast exhibit feeding behaviour within the Perth Canyon, which is an area of high krill abundance, particularly for Euphausia recurva. The importance of krill in marine food webs has led to a number of trophodynamic studies investigating their fatty acid and stable isotope compositions. In the south-east Indian Ocean, the suppression of upwelling by the dominant Leeuwin Current results in relatively oligotrophic waters, particularly during autumn and winter. Oligotrophic waters tend to be dominated by small autotrophic flagellates (i. e. dinoflagellates) and cyanobacteria. We relate biochemical data obtained for E. recurva, as well as Stylocheiron carinatum and Pseudeuphausia latifrons with their potential food source, phytoplankton, and one of their potential predators, the endangered pygmy blue whale (Balaenoptera musculus brevicauda) sampled in the Perth Canyon. Fatty acids of all three krill species were dominated by polyunsaturated fatty acids (PUFA; ~50%) largely comprised of omega-3 PUFA, which is typical for krill. The high docosahexaenoic acid (DHA) to eicosapentaenoic acid (EPA) ratio reflects a dinoflagellate, rather than a diatom diet, and the high oleic acid (18: 1 9) to vaccenic acid (18: 1 7) ratio is indicative of an omnivorous diet. Stable isotope analysis positions E. recurva as a first, possibly second order consumer (5. 8 - 8. 4 15N)and phytoplankton as the likely source of carbon (-18 to -24 13C) .The fatty acid composition of krill did not match that of the surface phytoplankton sampled, which was low in PUFA and more reflective of degraded and detrital material. This suggests that krill are not feeding at the surface, and may feed closer to the deep chlorophyll maximum. The outer blubber layer sampled from the pygmy blue whale was high in monounsaturated fatty acids (MUFA, 58%) rather than PUFA, and did not reflect the krill fatty acid composition. However, the high DHA to EPA ratio in the blubber indicated a diet originating from dinoflagellates, as found for krill. Stratification of fatty acids across blubber layers is common for marine mammals and the outer blubber layer for some species has been found to not accurately reflect the diet of the animal

The percutaneous absorption of soman in a damaged skin porcine model and the evaluation of WoundStat™ as a topical decontaminant

PURPOSE: The aim of this study was to evaluate a candidate haemostat (WoundStat™), down-selected from previous in vitro studies, for efficacy as a potential skin decontaminant against the chemical warfare agent pinacoyl methylfluorophosphonate (Soman, GD) using an in vivo pig model. MATERIALS AND METHODS: An area of approximately 3 cm2 was dermatomed from the dorsal ear skin to a nominal depth of 100 µm. A discrete droplet of 14C-GD (300 µg kg-1) was applied directly onto the surface of the damaged skin at the centre of the dosing site. Animals assigned to the treatment group were given a 2 g application of WoundStat™ 30 s after GD challenge. The decontamination efficacy of WoundStat™ against GD was measured by the direct quantification of the distribution of 14C-GD, as well as routine determination of whole blood cholinesterase and physiological measurements. RESULTS: WoundStat™ sequestered approximately 70% of the applied 14C-GD. Internal radiolabel recovery from treated animals was approximately 1% of the initially applied dose. Whole blood cholinesterase levels decreased to less than 10% of the original value by 15 min post WoundStat™ treatment and gradually decreased until the onset of apnoea or until euthanasia. All treated animals showed signs of GD intoxication that could be grouped into early (mastication, fasciculations and tremor), intermediate (miosis, salivation and nasal secretions) and late onset (lacrimation, body spasm and apnoea) effects. Two of the six WoundStat™ treated animals survived the study duration. CONCLUSIONS: The current study has shown that the use of WoundStat™ as a decontaminant on damaged pig ear skin was unable to fully protect against GD toxicity. Importantly, the findings indicate that the use of WoundStat™ in GD contaminated wounds would not exacerbate GD toxicity. These data suggest that absorbent haemostatic products may offer some limited functionality as wound decontaminants.Peer reviewedFinal Accepted Versio

Urinary tract infection in type 2 diabetic patients: risk factors and antimicrobial pattern

Background: Diabetes increases the risk of infection and the commonest amongst them are the ones involving the genitourinary tract. Diabetic patients are found to have an increase in the risk of developing urinary tract infection (UTI) by 60%. The study aimed to determine the causative pathogens and their antimicrobial pattern, identify risk factors associated in type 2 diabetic subjects having UTI. Methods: This was an observational study conducted in the medicine unit of a tertiary care hospital over a period of 8 months. A total of 619 (M:F 289:330) type 2 diabetic subjects were studied. History, clinical examinations, and the duration of diabetes were recorded in all patients at admission. Diabetes was diagnosed based on the WHO criteria. An immunoturbidimetric method was used to estimate glycosylated hemoglobin (HbA1C%). Diagnosis of UTI was made from midstream urine samples of patients if the urine cultures has >103 to >105 colony forming units (CFUs)/mL of a pathogen.Results: Among the 619 diabetic patients 220 patients had pus cells in urine but 72 patients had insignificant colony count. 90 (60.8%) patients were more than 60 years old, 48 (32.4%) were in the age group of 40-60 years and 10 (6.7%) were less than 40 years old. Among the 148 patients studied 52 (35.1%) were males and 96 (64.9%) were females. 116 (78.4%) had diabetes for more than 15 years and the rest had a duration lesser than 15 years. The HbA1C of patients with and without UTI were 10.2 ± 1.6 and 8.4 ± 1.3 respectively. Gram negative bacilli were isolated from 129 (87.2%) patients which included E. coli in 75 (50.7%), Klebsiella in 30 (20.3%), Pseudomonas species in 12 (8.1%) and Citrobacter in 12 (8.1%). Gram positive cocci were responsible for UTI in 15(10.1%) of subjects including Enterococcus in 13 (8.9%) and Staphylococcus in 2 (1.3%). Gram negative bacilli including E. coli, the Klebsiella species, pseudomonas and Citrobacter had good response to piperacillin-tazobactum, cefoperazone sulbactum, imipenam and amikacin. Gram positive cocci (Enterococcus and Staphylococcus) responsible for UTI showed good susceptibility to vancomycin (81 and 94% respectively) but a high resistance to ciprofloxacin and tetracyclines (68 and 57% respectively).Conclusions: Female gender, age and duration of diabetes were found to have increased risk factors for developing UTI in diabetes. Escherichia coli was the commonest organism causing UTI in diabetes which showed good response to piperacillin/tazobactum, cefoperazone-sulbactum, imipenam and amikacin.

Spectroscopic and electrochemical studies of di-heme thiosulphate dehydrogenases

Thiosulphate (SSO32-) and tetrathionate (S4O62-) are found in environments where numerous bacterial species live. Some of these bacteria express di-heme thiosulphate dehydrogenase (TsdA) enzymes that catalyse the interconversion of these sulphur compounds: 2 SSO32- ↔ S4O62- + 2 e- (EM = +198 mV) Electrons originate or terminate in this redox couple during respiration or photosynthesis in these bacteria. This is likely to give them a niche competitive advantage against other organisms lacking this enzyme in environments where these compounds are present. The catalytic site of TsdA enzymes is heme I which has the unusual axial ligand pairing His/Cys-. Heme II is an electron transfer site which has His/Met ligation in most TsdA enzymes (eg. Campylobacter jejuni (Cj) TsdA), but which has a redox-driven switch between His/Lys and His/Met ligation in two known TsdA enzymes (eg. Allochromatium vinosum (Av) TsdA). This work uses magnetic circular dichroism (MCD) to identify the heme ligation states for recombinant TsdA enzymes Cj TsdA and Av TsdA in solution and several variants where these ligands are substituted. Protein film electrochemistry (PFE) also characterised the electroactivity of the TsdA hemes in these proteins. This, in combination with electrochemically-poised MCD samples, was used to determine the mid-point potentials of native and variant hemes. Additionaly these techniques confirmed the Av TsdA heme II ligand switch and permitted investigation of its kinetics. Remarkably, the number of electrons transferred by Cj TsdA heme I in PFE is different to the number transferred by heme II. In comparison, the number of electrons transferred by the Av TsdA hemes are equal, although introducing Cj TsdA-like heme II ligation, introduces unequal electron transfer. Replacing the heme I cysteine ligand with methionine in Cj TsdA causes both hemes to have equal electron transfer. Liquid chromatography mass spectrometry (LC-MS)-resolved native covalent adducts to the heme I cysteine ligand, which modulate the electroactivity of heme I. A catalytic mechanism proposed for TsdA enzymes features covalent modification of the heme I cysteine ligand. Chemical treatments, substrates and substrate analogues have been used to change these modifications in a predictable manner, allowing for the characterisation of TsdA with defined heme I cysteine modifications. Combining data from PFE, MCD and LC-MS the previously-proposed catalytic mechanism is expanded further. Evidence suggests that the substrate-augmented site has adducts to the heme I cysteine which also control electron transfer to the TsdA hemes. This electron transfer is not adequately explained by conventional theory of redox centres in proteins suggesting that the reality in TsdA enzymes is more complex than this typically assumed model

Phadiatop Infant in the Diagnosis of Atopy in Children with Allergy-Like Symptoms

Background and Objective. Allergy-like symptoms such as wheezing and eczema are common in young children and an early diagnosis is important to initiate correct management. The objective of this study was to evaluate the diagnostic performance of Phadiatop Infant, an in vitro test for determination of early sensitisation to food and inhalant allergens. Patients and Methods. The study was conducted, retrospectively, using frozen sera from 122 children (median age 2.7 years) admitted to the hospital with suspected allergic symptoms. The doctor's diagnosis atopic/nonatopic was based on routinely used procedures such as clinical evaluation, SPT, total and allergen-specific IgE antibodies. The performance of Phadiatop Infant was evaluated in a blinded manner against this diagnosis. Results. Eighty-four of the 86 children classified as atopic showed a positive Phadiatop Infant test. Thirty-six were classified as nonatopic, 32 of who had a negative test. With a prevalence of atopy of 70% in this population, this gives a sensitivity of 98%, a specificity of 89%, and a positive and negative predictive value of 95% and 94%, respectively. Conclusion. The results from the present study suggest that Phadiatop Infant could be recommended as a complement to the clinical information in the differential diagnosis on IgE-mediated disease in young children with allergy-like symptoms

Tuberous sclerosis complex: a case report

Tuberous Sclerosis Complex is an autosomal dominant phakomatosis. This neurocutaneous disorder usually presents with seizures, facial angiofibroma and mental retardation (Vogt’s triad). Here we report a case where a 25 year old gentleman presented with recurrent seizures, and was diagnosed to have tuberous sclerosis complex