Glucose starvation-induced dispersal of pseudomonas aeruginosa biofilms is camp and energy dependent

Carbon starvation has been shown to induce a massive dispersal event in biofilms of the opportunistic pathogen Pseudomonas aeruginosa; however, the molecular pathways controlling this dispersal response remain unknown. We quantified changes in the proteome of P. aeruginosa PAO1 biofilm and planktonic cells during glucose starvation by differential peptide-fingerprint mass-spectrometry (iTRAQ). In addition, we monitored dispersal photometrically, as a decrease in turbidity/opacity of biofilms pre-grown and starved in continuous flow-cells, in order to evaluate treatments (e.g. inhibitors CCCP, arsenate, chloramphenicol, L-serine hydroxamate) and key mutants altered in biofilm development and dispersal (e.g. nirS, vfr, bdlA, rpoS, lasRrhlR, Pf4-bacteriophage and cyaA). In wild-type biofilms, dispersal started within five minutes of glucose starvation, was maximal after 2 h, and up to 60% of the original biomass had dispersed after 24 h of starvation. The changes in protein synthesis were generally not more than two fold and indicated that more than 100 proteins belonging to various classes, including carbon and energy metabolism, stress adaptation, and motility, were differentially expressed. For the different treatments, only the proton-ionophore CCCP or arsenate, an inhibitor of ATP synthesis, prevented dispersal of the biofilms. For the different mutants tested, only cyaA, the synthase of the intracellular second messenger cAMP, failed to disperse; complementation of the cyaA mutation restored the wild-type phenotype. Hence, the pathway for carbon starvation-induced biofilm dispersal in P. aeruginosa PAO1 involves ATP production via direct ATP synthesis and proton-motive force dependent step(s) and is mediated through cAMP, which is likely to control the activity of proteins involved in remodeling biofilm cells in preparation for planktonic survival. © 2012 Huynh et al

Accuracy of Multiple Pour Cast from Various Elastomer Impression Methods

The accurate duplicate cast obtained from a single impression reduces the profession clinical time, patient inconvenience, and extra material cost. The stainless steel working cast model assembly consisting of two abutments and one pontic area was fabricated. Two sets of six each custom aluminum trays were fabricated, with five mm spacer and two mm spacer. The impression methods evaluated during the study were additional silicone putty reline (two steps), heavy-light body (one step), monophase (one step), and polyether (one step). Type IV gypsum casts were poured at the interval of one hour, 12 hours, 24 hours, and 48 hours. The resultant cast was measured with traveling microscope for the comparative dimensional accuracy. The data obtained were subjected to Analysis of Variance test at significance level <0.05. The die obtained from two-step putty reline impression techniques had the percentage of variation for the height −0.36 to −0.97%, while diameter was increased by 0.40–0.90%. The values for one-step heavy-light body impression dies, additional silicone monophase impressions, and polyether were −0.73 to −1.21%, −1.34%, and −1.46% for the height and 0.50–0.80%, 1.20%, and −1.30% for the width, respectively

An interdisciplinary approach to the study of kiln firing: a case study from the Campus Galli open-air museum (southern Germany)

Pottery kilns are a common feature in the archaeological record of different periods. However, these pyrotechnological installations are still seldom the target of interdisciplinary investigations. To fill this gap in our knowledge, an updraft kiln firing experiment was run at the Campus Galli open-air museum (southern Germany) by a team consisting of experimental archaeologists, material scientists, geoarchaeologists, and palaeobotanists. The entire process from the preparation of the raw materials to the firing and opening of the kiln was carefully recorded with a particular focus on the study of the raw materials used for pottery making, as well as on fuel usage. The temperatures were monitored by thermocouples placed at different positions in the combustion and firing chambers. In addition, thermocouples were installed within the kiln wall to measure the temperature distribution inside the structure itself. Unfired raw materials as well as controlled and experimentally thermally altered ceramic samples were then characterised with an integrated analysis including ceramic petrography, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and portable X-ray fluorescence (pXRF). Our work provides data about mineralogical and microstructural developments in both pottery kiln structures and the ceramics produced in this type of installations. This is helpful to discuss the limits and potential of various scientific analyses commonly used in ancient ceramic pyrotechnological studies. Overall, our work contributes to a better understanding of updraft kiln technology and offers guidelines on how to address the study of this type of pyrotechnological installations using interdisciplinary research strategies

Assessment of Global Kidney Health Care Status.

Kidney disease is a substantial worldwide clinical and public health problem, but information about available care is limited.To collect information on the current state of readiness, capacity, and competence for the delivery of kidney care across countries and regions of the world.Questionnaire survey administered from May to September 2016 by the International Society of Nephrology (ISN) to 130 ISN-affiliated countries with sampling of key stakeholders (national nephrology society leadership, policy makers, and patient organization representatives) identified by the country and regional nephrology leadership through the ISN.Core areas of country capacity and response for kidney care.Responses were received from 125 of 130 countries (96%), including 289 of 337 individuals (85.8%, with a median of 2 respondents [interquartile range, 1-3]), representing an estimated 93% (6.8 billion) of the world's population of 7.3 billion. There was wide variation in country readiness, capacity, and response in terms of service delivery, financing, workforce, information systems, and leadership and governance. Overall, 119 (95%), 95 (76%), and 94 (75%) countries had facilities for hemodialysis, peritoneal dialysis, and kidney transplantation, respectively. In contrast, 33 (94%), 16 (45%), and 12 (34%) countries in Africa had facilities for hemodialysis, peritoneal dialysis, and kidney transplantation, respectively. For chronic kidney disease (CKD) monitoring in primary care, serum creatinine with estimated glomerular filtration rate and proteinuria measurements were reported as always available in only 21 (18%) and 9 (8%) countries, respectively. Hemodialysis, peritoneal dialysis, and transplantation services were funded publicly and free at the point of care delivery in 50 (42%), 48 (51%), and 46 (49%) countries, respectively. The number of nephrologists was variable and was low (<10 per million population) in Africa, the Middle East, South Asia, and Oceania and South East Asia (OSEA) regions. Health information system (renal registry) availability was limited, particularly for acute kidney injury (8 countries [7%]) and nondialysis CKD (9 countries [8%]). International acute kidney injury and CKD guidelines were reportedly accessible in 52 (45%) and 62 (52%) countries, respectively. There was relatively low capacity for clinical studies in developing nations.This survey demonstrated significant interregional and intraregional variability in the current capacity for kidney care across the world, including important gaps in services and workforce. Assuming the responses accurately reflect the status of kidney care in the respondent countries, the findings may be useful to inform efforts to improve the quality of kidney care worldwide

Intensive vocabulary learning: a case study

This paper describes a single-subject study of vocabulary acquisition. The subject, an L1 English speaker, was required to learn 300 vocabulary items in Arabic at a rate of 15 new words a day over a period of 20 days. The learning period was followed by immediate and delayed tests of receptive and productive knowledge of target items. The immediate test results indicated knowledge of almost all the target items, but this acquisition was temporary, with evident attrition of both receptive and productive knowledge in subsequent test events. The paper considers factors which might affect the uptake and retention of items, and uses a matrix analysis to make long-term projections for vocabulary acquisition

Kidney care in low- and middle-income countries

Optimal kidney care requires a trained nephrology workforce, essential healthcare services, and medications. This study aimed to identify the access to these resources on a global scale using data from the multinational survey conducted by the International Society of Nephrology (ISN) (Global Kidney Health Atlas (GKHA) project), with emphasis on developing nations. For data analysis, the 125 participating countries were sorted into the 4 World Bank income groups: low income (LIC), lower-middle income (LMIC), upper-middle income (UMIC), and high income (HIC). A severe shortage of nephrologists was observed in LIC and LMIC with &lt; 5 nephrologists per million population. Many LIC were unable to access estimated glomerular filtration rate (eGFR) and albuminuria (proteinuria) tests in primary-care levels. Acute and chronic hemodialysis was available in most countries, although acute and chronic peritoneal dialysis access was severely limited in LIC (24% and 35%, respectively). Most countries had kidney transplantation access, except for LIC (12%). HIC and UMIC funded their renal replacement therapy (RRT) and renal medications primarily through public means, whereas LMIC and LIC required private and out-of-pocket contributions. In conclusion, this study found a huge gap in the availability and access to trained nephrology workforce, tools for diagnosis and management of CKD, RRT, and funding of RRT and essential medications in LIC and LMIC

Kidney care in low- and middle-income countries

Optimal kidney care requires a trained nephrology workforce, essential healthcare services, and medications. This study aimed to identify the access to these resources on a global scale using data from the multinational survey conducted by the International Society of Nephrology (ISN) (Global Kidney Health Atlas (GKHA) project), with emphasis on developing nations. For data analysis, the 125 participating countries were sorted into the 4 World Bank income groups: low income (LIC), lower-middle income (LMIC), upper-middle income (UMIC), and high income (HIC). A severe shortage of nephrologists was observed in LIC and LMIC with < 5 nephrologists per million population. Many LIC were unable to access estimated glomerular filtration rate (eGFR) and albuminuria (proteinuria) tests in primary-care levels. Acute and chronic hemodialysis was available in most countries, although acute and chronic peritoneal dialysis access was severely limited in LIC (24% and 35%, respectively). Most countries had kidney transplantation access, except for LIC (12%). HIC and UMIC funded their renal replacement therapy (RRT) and renal medications primarily through public means, whereas LMIC and LIC required private and out-of-pocket contributions. In conclusion, this study found a huge gap in the availability and access to trained nephrology workforce, tools for diagnosis and management of CKD, RRT, and funding of RRT and essential medications in LIC and LMIC