Studies on the filtration, feeding and excretion rates in Perna viridis, Marcia cor and Crassostrea gryphoides (Mollusca: Bivalvia) using P³² labelled Ankistrodesmes

The study deals with a series of experiments to investigate feeding and excretion in three species of bivalves: Perna viridis (Linné), Marcia cor (Sowerby) and Cassostrea gryphoides (Gould) from Manora Channel, Karachi. Bivalves were fed with suspensions of Ankistrodesmes labelled with P³². These animals showed a considerable variation in the average filtration rates depending upon species and the body lenght. Exceptionally high content of the P³² introduced with Akistrodesmes, got excreted as pseudofaeces and faeces within first three days following its absorption as a meal. The assimilated P³² is partly released as faecal material and its major proportion is directly transferred to the solution. As expexted the gonad and kidney are the main organs found responsible for excretion as comared to other body parts. Although, the assimilated P³² is mostly concentrated in the digestive glands, the results also show a significant presence of P³² in the gonads. Accumulation of P³² was the least in the foot

Can guidelines improve referral to elective surgical specialties for adults? A systematic review

Aim To assess effectiveness of guidelines for referral for elective surgical assessment. Method Systematic review with descriptive synthesis. Data sources Medline, EMBASE, CINAHL and Cochrane database up to 2008. Hand searches of journals and websites. Selection of studies Studies evaluated guidelines for referral from primary to secondary care, for elective surgical assessment for adults. Outcome measures Appropriateness of referral (usually measured as guideline compliance) including clinical appropriateness, appropriateness of destination and of pre-referral management (eg, diagnostic investigations), general practitioner knowledge of referral appropriateness, referral rates, health outcomes and costs. Results 24 eligible studies (5 randomised control trials, 6 cohort, 13 case series) included guidelines from UK, Europe, Canada and the USA for referral for musculoskeletal, urological, ENT, gynaecology, general surgical and ophthalmological conditions. Interventions varied from complex (“one-stop shops”) to simple guidelines. Four randomized control trials reported increases in appropriateness of pre-referral care (diagnostic investigations and treatment). No evidence was found for effects on practitioner knowledge. Mixed evidence was reported on rates of referral and costs (rates and costs increased, decreased or stayed the same). Two studies reported on health outcomes finding no change. Conclusions Guidelines for elective surgical referral can improve appropriateness of care by improving prereferral investigation and treatment, but there is no strong evidence in favour of other beneficial effects

Respiratory arrest in a child after flushing of pancuronium from the dead space of intravenous cannula

It is common practice for patients admitted to Intensive Care Units to have indwelling intravenous cannulae. Sometimes these cannulae are used only for the administration of drugs and are closed otherwise. Residual drugs in the deadspace of these intravenous cannulae as well as connected stoppers or 3-way stopcocks can later be flushed unknowingly. We would like to report a case in which inadvertent flushing of residual pancuronium caused complete muscle paralysis and respiratory arrest in a young child

SATL Based Lesson for Teaching Grignard Reagents in Synthetic Organic Chemistry

Synthesizing new products from raw materials has been very popular aspects of research in organic chemistry. Traditionally, Grignard reagent has been very vital component of such synthetic procedures. Hence learning of various issues concerning with applications of Grignard reactions in synthetic organic chemistry is vital for enhancing the students creative capability. In this paper we will illustrate the uses of SATL methodology, which is recently getting popular [1- 3], in an SATL-based model lesson concerning teaching and learning of synthetic organic reactions related to Grignard reagents

Study of the histidine complex of uranium(IV): synthesis, spectrophotometric, magnetic and electrochemical properties

We synthesized the novel histidine complex of uranium(IV). A 1:3 mole ratio was found between metal and ligand by the mole ratio method, while –NH2 and –COO– groups of histidine behave as coordinating sites. The IR spectra confirmed the lone pair donating or coordinating sites. The elemental analysis confirmed the stoichiometry. The bathochromic shift with an increase in the optical density in the UV-Visible range indicated that the compound and its central metal ion hold uniform electronic charge distribution. The electrochemical results indicated a quasi-reversible (neither completely reversible nor completely irreversible) oxidation of the complex to its uranium(V) product at the platinum working electrode. The quasi-reversible process shows a comparatively slow electron transfer (ET) rate with the heterogeneous electron transfer rate constant ‘ks’ (3.4 ×  10–4 cm s-1) at 50 mV s-1 and 305 ± 0.5 K. The kinetics such as diffusion and charge transfer lead the reaction with an ECE (electrochemical–chemical–electrochemical) mechanism. The thermodynamic parameters of activation such as ΔH*; 4.257 kJ mol–1, ΔS*; -2.519 × 10–3 J mol–1 K–1 and ΔG* 4.26 kJ mol–1 helped to propose an associative mechanism of the electron transfer at the platinum working electrode.                     KEY WORDS: Uranium, Histidine, Spectroscopy, Electrochemistry, Kinetics   Bull. Chem. Soc. Ethiop. 2020, 34(3), 557-569.  DOI: https://dx.doi.org/10.4314/bcse.v34i3.1

CONCOMITANT GASTRIC AND LUNG UPTAKE OF TC-99M MDP ON BONE SCAN IN A PATIENT WITH DIFFUSE LARGE B-CELL NON-HODGKIN’S LYMPHOMA

Extra osseous uptake of Tc-99m Methylene Di Phosphonate (MDP) is not an uncommon finding on skeletal scintigraphy. However, concomitant lung and gastric uptake is a rare presentation. We presented a case report of a young male whose bone scan revealed lung and stomach uptake with a cold lesion over T7 vertebra. CT guided biopsy revealed diffuse large B-cell Non-Hodgkin’s lymphoma. Lung and gastric uptake of Tc-99m MDP on bone scan guides the reporting physician about the soft tissue calcinosis due to hypercalcemia associated with either malignant or non-malignant conditions

Assessing the cascading impacts of natural disasters in a multi-layer behavioral network framework

Natural disasters negatively impact regions and exacerbate socioeconomic vulnerabilities. While the direct impacts of natural disasters are well understood, the channels through which these shocks spread to non-affected regions, still represents an open research question. In this paper we propose modelling socioeconomic systems as spatially-explicit, multi-layer behavioral networks, where the interplay of supply-side production, and demand-side consumption decisions, can help us understand how climate shocks cascade. We apply this modelling framework to analyze the spatial-temporal evolution of vulnerability following a negative food-production shock in one part of an agriculture-dependent economy. Simulation results show that vulnerability is cyclical, and its distribution critically depends on the network density and distance from the epicenter of the shock. We also introduce a new multi-layer measure, the Vulnerability Rank (VRank), which synthesizes various location-level risks into a single index. This framework can help design policies, aimed to better understand, effectively respond, and build resilience to natural disasters. This is particularly important for poorer regions, where response time is critical and financial resources are limited

The m->0 limit for massive graviton in dS_4 and AdS_4. How to circumvent the van Dam-Veltman-Zakharov discontinuity

We show that, by considering physics in dS_4 or AdS_4 spacetime, one can circumvent the van Dam - Veltman - Zakharov theorem which requires that the extra polarization states of a massive graviton do not decouple in the massless limit. It is shown that the smoothness of the m->0 limit is ensured if the H (``Hubble'') parameter, associated with the horizon of the dS_4 or AdS_4 space, tends to zero slower than the mass of the graviton m.Comment: 11 pages, references added, minor typos correcte

A P-loop Mutation in Gα Subunits Prevents Transition to the Active State: Implications for G-protein Signaling in Fungal Pathogenesis

Heterotrimeric G-proteins are molecular switches integral to a panoply of different physiological responses that many organisms make to environmental cues. The switch from inactive to active Gαβγ heterotrimer relies on nucleotide cycling by the Gα subunit: exchange of GTP for GDP activates Gα, whereas its intrinsic enzymatic activity catalyzes GTP hydrolysis to GDP and inorganic phosphate, thereby reverting Gα to its inactive state. In several genetic studies of filamentous fungi, such as the rice blast fungus Magnaporthe oryzae, a G42R mutation in the phosphate-binding loop of Gα subunits is assumed to be GTPase-deficient and thus constitutively active. Here, we demonstrate that Gα(G42R) mutants are not GTPase deficient, but rather incapable of achieving the activated conformation. Two crystal structure models suggest that Arg-42 prevents a typical switch region conformational change upon Gαi1(G42R) binding to GDP·AlF4− or GTP, but rotameric flexibility at this locus allows for unperturbed GTP hydrolysis. Gα(G42R) mutants do not engage the active state-selective peptide KB-1753 nor RGS domains with high affinity, but instead favor interaction with Gβγ and GoLoco motifs in any nucleotide state. The corresponding Gαq(G48R) mutant is not constitutively active in cells and responds poorly to aluminum tetrafluoride activation. Comparative analyses of M. oryzae strains harboring either G42R or GTPase-deficient Q/L mutations in the Gα subunits MagA or MagB illustrate functional differences in environmental cue processing and intracellular signaling outcomes between these two Gα mutants, thus demonstrating the in vivo functional divergence of G42R and activating G-protein mutants