36 research outputs found

    Studies on riverine flora of Pamba river basin, Kerala

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    Riparian forests are ecotonal assemblage of aquatic and terrestrial habitats. The composition of riparian forests of Pamba River is an amalgamation of riverine, evergreen, deciduous and wetland flora. The floristic investigation of the riparian forests of Pamba river basin revealed taxonomically 433 species which include 410 angiosperms, 3 gymnosperms and 20 pteridophytes. The dominant families based on the number of species are Poaceae, Euphorbiaceae, Rubiaceae, Cyperaceae and Fabaceae. The flora consists of a diverse blend of 99 evergreen, 36 deciduous, 50 wetland, 15 shola-grassland, 46 cultivated and 44 riverine components. The river basin holds 17.5 % endemism and 17 RET species. The riparian tree species identified in the present investigation are _Barringtonia racemosa_, _Calophyllum inophyllum_, _Crateva magna_, _Dillenia indica_, _Elaeocarpus tuberculatus_, _Garcinia gummi-gutta_, _Humboldtia vahliana_, _Largestromea speciosa_, _Neolamarkia kadamba_, _Ochrenauclea missionis_, _Syzigium salicifolium_, _Talipatri tiliaceaum_ and _Trewia nudiflora_. It is assumed that these potential tree species might have a crucial role to maintain the ecological integrity of the riparian zones and floodplain for the restoration of Pamba river

    Well-defined alkyl functional poly(styrene-co-maleic anhydride) architectures as pour point and viscosity modifiers for lubricating oil

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    A series of well-defined poly(styrene-co-maleic anhydride) copolymers (PSMA) allowing controlled grafting density and distribution of long alkyl side chains (C12 and C22) was synthesized and investigated as viscosity modifiers for two mineral base oils (API Group II and III). The PSMA copolymer backbones (multisite, multiblock, diblock, alternating linear, alternating star) were synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization using an industrial chain transfer agent (CTA-Ester) and subsequently esterified using long alkyl alcohols (lauryl and behenyl alcohol). The influence of grafting density and distribution, backbone, and side chain length of the polymers on the pour point (PPT) of blended fluids was investigated. The viscosity index (VI) and thickening efficiency (TE) were also studied. All the polymers showed improvement of base oil properties (PPT, VI, and TE). The alternating PSMA materials (high density of side chains) functionalized with shorter alkyl chains (C12) were found to be more efficient as pour point depressants (PPDs), regardless of the oil type and the molar mass or architecture of the polymer tested (ΔPPT = −36 °C and −30 °C in oil groups II and III, respectively). A poly(lauryl acrylate) (PLAc) sample was also synthesized and used for comparison, showing the benefit of having styrene in the copolymer additive composition. The VI and TE properties were shown to be dependent on molar mass and architectures used, where the best results were obtained for the high molar mass PSMA star

    Influence of grafting density and distribution on material properties using well-defined alkyl functional poly(styrene-co-maleic anhydride) architectures synthesized by RAFT

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    Poly(styrene-co-maleic anhydride) copolymers (PSMA) with controlled number and distribution of maleic anhydride (MAnh) units were synthesized by reversible addition–fragmentation chain transfer polymerization using chain-transfer agents (CTA) suitable for industrial scale processes. Linear- and star-shaped alternating PSMA polymers were prepared in a single-step synthesis, while a one-pot sequential chain-extension strategy was utilized to prepare diblock, multiblock, and multisite copolymer architectures. A library of grafted PSMAs with controlled density and distribution of side chains was achieved by the subsequent grafting of long aliphatic alcohol chains (C22) to the MAnh units. The influence of structure, composition, and long alkyl chain addition on PSMAs behavior in solution was studied with triple-detection size exclusion chromatography, while their thermal properties were examined by thermogravimetric analysis and differential scanning calorimetry. Overall, the side chain density and distribution did not impact the polymer conformations in solution (random coil); however, an effect on the molecular size (Rh) and structure density (intrinsic viscosity) were observed. The materials density was shown to be dependent on polymer architectures as lower intrinsic viscosity was observed for the star copolymer. All the materials had similar degradation points (400 °C), while the rate of degradation showed a dependence on the MAnh content and polymeric architecture. Ultimately, the grafting of long aliphatic side chains (crystalline) onto the PSMA backbone, even at low density, was shown to drastically change the microphase ordering, as all the grafted copolymers became semicrystalline. The difference of the crystallization temperature between low density multisite materials (Tc ≈ 8 °C) and the high density alternating material (Tc ≈ 40 °C) highlights the major importance of controlling copolymer composition and structure to tune material properties

    Indian Ocean humpback dolphin stranded at Arthunkal landing centre, Kerala

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    On November 2, 2022, the carcass of a dead dolphin, Sousa plumbea (Indian Ocean Humpback Dolphin), was discovered at the Arthunkal landing centre in Alapuzha, Kerala (9039’42.0”N 76017’29.5”E)

    Single infrastructure utility provision to households: Technological feasibility study

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    This paper contemplates the future of utility infrastructure, and considers whether an “All-in-One” approach could supply all necessary utility services to tomorrow's households. The intention is not to propose infrastructure solutions that are currently technically feasible or justifiable, however; the objective is to present visions of future infrastructure that would only be possible with new advances in science and technology, or significant improvements and adaptations of existing knowledge and techniques. The All-in-One vision is explored using several vignettes, each of which envisions a novel, multi-functional infrastructure for serving future communities. The vignettes were conceived using imaginative exercises and brain-storming activities; each was then rooted in technological and scientific feasibility, as informed by extensive literature searches and the input of domain leaders. The vignettes tell their own stories, and we identify the challenges that would need to be overcome to make these visions into reality. The main aim of this work is to encourage radical approaches to thinking about future infrastructure provision, with a focus on rationalisation, efficiency, sustainability and resilience in preparation for the challenging times ahead. The All-in-One concept introduces the possibility of a unified and singular system for infrastructure service provision; this work seeks to explore the possibility space opened thereby

    Investigation of LKB1 Ser<sup>431</sup> phosphorylation and Cys<sup>433</sup> farnesylation using mouse knockin analysis reveals an unexpected role of prenylation in regulating AMPK activity

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    The LKB1 tumour suppressor protein kinase functions to activate two isoforms of AMPK (AMP-activated protein kinase) and 12 members of the AMPK-related family of protein kinases. The highly conserved C-terminal residues of LKB1 are phosphorylated (Ser(431)) by PKA (cAMP-dependent protein kinase) and RSK (ribosomal S6 kinase) and farnesylated (Cys(433)) within a CAAX motif. To better define the role that these post-translational modifications play, we created homozygous LKB1(S431A/S431A) and LKB1(C433S/C433S) knockin mice. These animals were viable, fertile and displayed no overt phenotypes. Employing a farnesylation-specific monoclonal antibody that we generated, we established by immunoprecipitation that the vast majority, if not all, of the endogenous LKB1 is prenylated. Levels of LKB1 localized at the membrane of the liver of LKB1(C433S/C433S) mice and their fibroblasts were reduced substantially compared with the wild-type mice, confirming that farnesylation plays a role in mediating membrane association. Although AMPK was activated normally in the LKB1(S431A/S431A) animals, we unexpectedly observed in all of the examined tissues and cells taken from LKB1(C433S/C433S) mice that the basal, as well as that induced by the AMP-mimetic AICAR (5-amino-4-imidazolecarboxamide riboside), AMPK activation, phenformin and muscle contraction were significantly blunted. This resulted in a reduced ability of AICAR to inhibit lipid synthesis in primary hepatocytes isolated from LKB1(C433S/C433S) mice. The activity of several of the AMPK-related kinases analysed [BRSK1 (BR serine/threonine kinase 1), BRSK2, NUAK1 (NUAK family, SNF1-like kinase 1), SIK3 (salt-inducible kinase 3) and MARK4 (MAP/microtubule affinity-regulating kinase 4)] was not affected in tissues derived from LKB1(S431A/S431A) or LKB1(C433S/C433S) mice. Our observations reveal for the first time that farnesylation of LKB1 is required for the activation of AMPK. Previous reports have indicated that a pool of AMPK is localized at the plasma membrane as a result of myristoylation of its regulatory AMPKÎČ subunit. This raises the possibility that LKB1 farnesylation and myristoylation of AMPKÎČ might promote the interaction and co-localization of these enzymes on a two-dimensional membrane surface and thereby promote efficient activation of AMPK

    Opsonic phagocytosis in chronic obstructive pulmonary disease is enhanced by Nrf2 agonists

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    Rationale: Previous studies have identified defects in bacterial phagocytosis by alveolar macrophages (AM) in patients with chronic obstructive pulmonary disease (COPD) but the mechanisms and clinical consequences remain incompletely defined. Objectives: To examine the effect of COPD on AM phagocytic responses and identify the mechanisms, clinical consequences and potential for therapeutic manipulation of these defects. Methods: We isolated alveolar macrophages (AM) and monocyte-derived macrophages (MDM) from a cohort of COPD patients and controls within the MRC COPD-MAP consortium and measured phagocytosis of bacteria in relation to opsonic conditions and clinical features. Measurements and Main Results: COPD AM and MDM have impaired phagocytosis of S. pneumoniae. COPD AM have a selective defect in uptake of opsonized bacteria, despite the presence of anti-pneumococcal antibodies in bronchoalveolar lavage, not observed in MDM or healthy donor’s AM. AM defects in phagocytosis in COPD are significantly associated with exacerbation frequency, isolation of pathogenic bacteria and health related quality of life scores. Bacterial binding and initial intracellular killing of opsonized bacteria in COPD AM was not reduced. COPD AM have reduced transcriptional responses to opsonized bacteria, including cellular stress responses that include transcriptional modules involving antioxidant defenses and Nrf2-regualted genes. Agonists of the cytoprotective transcription factor Nrf2 (sulforaphane and Compound) reverse defects in phagocytosis of S. pneumoniae and non-type able Haemophilus influenzae by COPD. Conclusions: Patients with COPD have clinically relevant defects in opsonic phagocytosis by AM, associated with impaired transcriptional responses to cellular stress, which are reversed by therapeutic targeting with Nrf2 agonists

    The therapeutic potential of epigenetic manipulation during infectious diseases.

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    Epigenetic modifications are increasingly recognized as playing an important role in the pathogenesis of infectious diseases. They represent a critical mechanism regulating transcriptional profiles in the immune system that contributes to the cell-type and stimulus specificity of the transcriptional response. Recent data highlight how epigenetic changes impact macrophage functional responses and polarization, influencing the innate immune system through macrophage tolerance and training. In this review we will explore how post-translational modifications of histone tails influence immune function to specific infectious diseases. We will describe how these may influence outcome, highlighting examples derived from responses to acute bacterial pathogens, models of sepsis, maintenance of viral latency and HIV infection. We will discuss how emerging classes of pharmacological agents, developed for use in oncology and other settings, have been applied to models of infectious diseases and their potential to modulate key aspects of the immune response to bacterial infection and HIV therapy

    BHPR research: qualitative1. Complex reasoning determines patients' perception of outcome following foot surgery in rheumatoid arhtritis

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    Background: Foot surgery is common in patients with RA but research into surgical outcomes is limited and conceptually flawed as current outcome measures lack face validity: to date no one has asked patients what is important to them. This study aimed to determine which factors are important to patients when evaluating the success of foot surgery in RA Methods: Semi structured interviews of RA patients who had undergone foot surgery were conducted and transcribed verbatim. Thematic analysis of interviews was conducted to explore issues that were important to patients. Results: 11 RA patients (9 ♂, mean age 59, dis dur = 22yrs, mean of 3 yrs post op) with mixed experiences of foot surgery were interviewed. Patients interpreted outcome in respect to a multitude of factors, frequently positive change in one aspect contrasted with negative opinions about another. Overall, four major themes emerged. Function: Functional ability & participation in valued activities were very important to patients. Walking ability was a key concern but patients interpreted levels of activity in light of other aspects of their disease, reflecting on change in functional ability more than overall level. Positive feelings of improved mobility were often moderated by negative self perception ("I mean, I still walk like a waddling duck”). Appearance: Appearance was important to almost all patients but perhaps the most complex theme of all. Physical appearance, foot shape, and footwear were closely interlinked, yet patients saw these as distinct separate concepts. Patients need to legitimize these feelings was clear and they frequently entered into a defensive repertoire ("it's not cosmetic surgery; it's something that's more important than that, you know?”). Clinician opinion: Surgeons' post operative evaluation of the procedure was very influential. The impact of this appraisal continued to affect patients' lasting impression irrespective of how the outcome compared to their initial goals ("when he'd done it ... he said that hasn't worked as good as he'd wanted to ... but the pain has gone”). Pain: Whilst pain was important to almost all patients, it appeared to be less important than the other themes. Pain was predominately raised when it influenced other themes, such as function; many still felt the need to legitimize their foot pain in order for health professionals to take it seriously ("in the end I went to my GP because it had happened a few times and I went to an orthopaedic surgeon who was quite dismissive of it, it was like what are you complaining about”). Conclusions: Patients interpret the outcome of foot surgery using a multitude of interrelated factors, particularly functional ability, appearance and surgeons' appraisal of the procedure. While pain was often noted, this appeared less important than other factors in the overall outcome of the surgery. Future research into foot surgery should incorporate the complexity of how patients determine their outcome Disclosure statement: All authors have declared no conflicts of interes

    Clinical features and management of individuals admitted to hospital with monkeypox and associated complications across the UK: a retrospective cohort study.

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    BACKGROUND The scale of the 2022 global mpox (formerly known as monkeypox) outbreak has been unprecedented. In less than 6 months, non-endemic countries have reported more than 67 000 cases of a disease that had previously been rare outside of Africa. Mortality has been reported as rare but hospital admission has been relatively common. We aimed to describe the clinical and laboratory characteristics and outcomes of individuals admitted to hospital with mpox and associated complications, including tecovirimat recipients. METHODS In this cohort study, we undertook retrospective review of electronic clinical records and pathology data for all individuals admitted between May 6, and Aug 3, 2022, to 16 hospitals from the Specialist and High Consequence Infectious Diseases Network for Monkeypox. The hospitals were located in ten cities in England and Northern Ireland. Inclusion criteria were clinical signs consistent with mpox and MPXV DNA detected from at least one clinical sample by PCR testing. Patients admitted solely for isolation purposes were excluded from the study. Key outcomes included admission indication, complications (including pain, secondary infection, and mortality) and use of antibiotic and anti-viral treatments. Routine biochemistry, haematology, microbiology, and virology data were also collected. Outcomes were assessed in all patients with available data. FINDINGS 156 individuals were admitted to hospital with complicated mpox during the study period. 153 (98%) were male and three (2%) were female, with a median age of 35 years (IQR 30-44). Gender data were collected from electronic patient records, which encompassed full formal review of clincian notes. The prespecified options for data collection for gender were male, female, trans, non-binary, or unknown. 105 (71%) of 148 participants with available ethnicity data were of White ethnicity and 47 (30%) of 155 were living with HIV with a median CD4 count of 510 cells per mm (IQR 349-828). Rectal or perianal pain (including proctitis) was the most common indication for hospital admission (44 [28%] of 156). Severe pain was reported in 89 (57%) of 156, and secondary bacterial infection in 82 (58%) of 142 individuals with available data. Median admission duration was 5 days (IQR 2-9). Ten individuals required surgery and two cases of encephalitis were reported. 38 (24%) of the 156 individuals received tecovirimat with early cessation in four cases (two owing to hepatic transaminitis, one to rapid treatment response, and one to patient choice). No deaths occurred during the study period. INTERPRETATION Although life-threatening mpox appears rare in hospitalised populations during the current outbreak, severe mpox and associated complications can occur in immunocompetent individuals. Analgesia and management of superimposed bacterial infection are priorities for patients admitted to hospital
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