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Between Life and Death: Continuing Bonds at Late Neolithic Tell Sabi Abyad, SyriaIn this paper, we pay tribute to the career-long interest of Prof Peter Akkermans in the mortuary practices of prehistoric southwest Asia. It highlights the significant discovery of burial grounds at Tell Sabi Abyad and the diverse range of mortuary behaviours observed at this key Late Neolithic site. While traditional approaches to the treatment of the dead often focus on social status, this paper proposes a fresh perspective by examining the agency of the bereaved and the impact of their emotional needs on mortuary rituals. Drawing on an extensive dataset of over 300 burials, the paper centres on a subset of burials from Tell Sabi Abyad I and III, dating back to the 7th and early 6th millennium BCE. In contrast to the typical interments, these burials reveal extended interaction with the deceased, involving bodily manipulation and close spatial proximity to the living. In this paper, we delve into new interpretations of this evidence, shedding light on the emotional relationships between the living and the dead. We explore possible motivations behind maintaining a tangible connection with the deceased and examine whether such practices offer insights into experiences of grief and bereavement – dimensions often overlooked in archaeological analysis. By incorporating emotion, sensory experiences, and mourning into the interpretation of mortuary evidence, in this paper, we aim to enrich our understanding of mortuary practices’ significance in southwest Asia’s prehistoric context.
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Geophysical investigations within the Latus Dextrum of Porolissum Fort, Northwestern Romania - The layout of a Roman edificeThis paper summarizes the results of a recent geophysical investigation carried out at Porolissum, which is considered to be one of the most significant Roman sites in Romania. The geophysical survey was carried out within the latus dextrum of the fort, which is the same location that had been the subject of earlier geophysical surveys as well as older archaeological excavations (1970s) that had uncovered a multiroom building. A cesium vapor total field magnetometer and a multi-electrode resistivity meter for a dense Electrical Resistivity Tomography (ERT) survey were used. Eighty parallel ERT profiles in combination with the emerging total field magnetic data and an antecedent magnetic survey allowed us to complete a more precise interpretation regarding the building that once existed on the left side of Porolissum’s Principia (the commander’s house). In contrast to the magnetic survey, which only reveals a part of the building’s architecture, the ERT survey provides a comprehensive view of the structure’s layout. More than 20 rooms could be positively identified, and the existence of further rooms might be deduced from the data. The ERT scan revealed the existence of the building’s northern external wall as well, which is not reflected on the magnetic map. Because some parts of the building are not visible on the magnetic map, we can assume that the building was constructed with at least two types of rocks (magmatic and sedimentary). In addition to the archaeological interpretation of the geophysical anomalies, a number of discussions concerning the connection between our survey and the geology of the area were held. The complementarity of the magnetic and resistivity results prompted us to conceive a preliminary 3D reconstruction of the building. Even if the building function is unknown in the absence of reliable archaeological data, it could have been a storage building, a second praetorium, a valetudinarium (hospital), or an armamentarium (weapons storage building). The illustrative reconstruction was completed taking into consideration that the building was a Roman military hospital, which, based on the available data, may be considered a credible assumption.
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Biodegradable Polymer Composites of Metal Organic Framework-5 (MOF-5) for the Efficient and Sustained Delivery of Cephalexin and MetronidazoleThe sustained and controlled delivery of antimicrobial drugs has been largely studied using nanomaterials, like metal organic frameworks (MOFs), and various polymers. However, not much attention has been given to combining MOFs and biodegradable polymers towards the potentially more sustained release of active pharmaceutical ingredients. Herein, we report a comparative study of two widely used antimicrobial drugs, cephalexin and metronidazole, from zinc-based MOF-5 incorporated into biodegradable polycaprolactone (PCL) and poly-lactic glycolic acid (PLGA) composites. Cephalexin and metronidazole were separately loaded into MOF-5 post-synthetically, followed by their integration into biodegradable PLGA and PCL composites. The pristine MOF-5 and the loaded MOFs were thoroughly characterised using Fourier-transformed infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and powder X-ray diffraction (PXRD). Ultraviolet-visible (UV-Vis) spectroscopy studies were carried out to assess the release of the drugs in PBS for up to 72 h, showing a cumulative release of 24.95 wt% and 27.84 wt% for cephalexin and metronidazole, respectively. The antibacterial properties of the pristine MOF, pure drugs, drug-loaded MOFs and the loaded composites were assessed against Gram-positive and Gram-negative bacterial strains, Staphylococcus aureus or Staphylococcus epidermidis and Escherichia coli or Acinetobacter baumanii, respectively. A cephalexin-loaded MOF-5 composite of PCL (PCL-ceph@MOF-5) showed the best efficiency for the controlled release of drugs to inhibit the growth of the bacteria compared to the other composites. This study demonstrates that the combination of MOFs with biodegradable polymers can provide an efficient platform for the sustained release of antimicrobial drugs and can be a promising tool to manage antimicrobial resistance (AMR).
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Controlled delivery of ciprofloxacin using zirconium-based MOFs and poly-caprolactone compositesWith antimicrobial resistance (AMR) increasing at an alarming rate, there is a need to develop better antibiotic delivery platforms at the point of need, to reduce over-exposure to antibiotics that are delivered systemically. Recent studies have suggested the use of metal-organic frameworks (MOFs) as potential vehicles for controlled and efficient delivery of various active pharmaceutical ingredients (APIs). Development of MOF-polymer composite materials can assist in the development of medical devices that can deliver APIs to local sites in a targeted approach. This study reports the encapsulation of a widely used antibiotic - ciprofloxacin (CIP) - into two Zr-based MOFs (UiO-66 and UiO-66-NH2) and their subsequent integration into a biodegradable polymer; polycaprolactone (PCL), via solvent casting, to obtain a PCL-MOF composite membrane. The MOFs and PCL-MOF composites were characterised by Fourier-transformed infrared (FT-IR) spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The results demonstrated that the structural integrity of the pristine MOFs was maintained after drug loading and incorporation into the PCL membranes. The ciprofloxacin release was studied using ultraviolet–visible (UV–Vis) spectroscopy, and the results showed that the PCL-MOF composites had a more controlled drug release profile compared to the MOF alone, when monitored for seven days in phosphate buffered saline (PBS) and accelerated ageing (AA) release media. In addition, release studies showed pH-dependence with faster release of ciprofloxacin at both acidic and basic conditions. Antimicrobial assay showed excellent efficacy for both CIP-loaded MOFs and their PCL composites against S. aureus and E. coli, a Gram-negative and Gram-positive bacterium, respectively, with inhibition zone as high as >50 mm against E. coli for UiO-66-NH2-CIP, indicating their potential applications in purpose-specific medical devices.
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Roman auxiliary fort in Pojejena (Caraș-Severin County, Romania). The results of non-invasive and archival research (2017-2019)A non-destructive survey conducted in 2017–2019 in the proximity of the auxiliary fort brought forth new data regarding the military base on the bank of the Danube, in the frontier zone between the Roman provinces of Moesia Superior and Dacia Inferior. It became clear that the previously acknowledged large stone fort was preceded by an unknown small earth-and-timber fort likely dated to the late 1st – early 2nd century. Analysis of the internal planning of the large fort, as well as the results of test trenching near the East Gate not only allowed to verify some geophysical results but also gave insight into the chronology of the large fort and contributed to the discussion of the changes to the fort’s garrison. The evidence shows that the base functioned until the 260s CE, and while the Roman military was probably present in the area at some point in the 4th century, it was a relatively short episode during an attempt to reconquer the Dacian riverbank.
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Multi-cavity molecular descriptor interconnections: Enhanced protocol for prediction of serum albumin drug bindingThe role of human serum albumin (HSA) in the transport of molecules predicates its involvement in the determination of drug distribution and metabolism. Optimization of ADME properties are analogous to HSA binding thus this is imperative to the drug discovery process. Currently, various in silico predictive tools exist to complement the drug discovery process, however, the prediction of possible ligand-binding sites on HSA has posed several challenges. Herein, we present a strong and deeper-than-surface case for the prediction of HSA-ligand binding sites using multi-cavity molecular descriptors by exploiting all experimentally available and crystallized HSA-bound drugs. Unlike previously proposed models found in literature, we established an in-depth correlation between the physicochemical properties of available crystallized HSA-bound drugs and different HSA binding site characteristics to precisely predict the binding sites of investigational molecules. Molecular descriptors such as the number of hydrogen bond donors (nHD), number of heteroatoms (nHet), topological polar surface area (TPSA), molecular weight (MW), and distribution coefficient (LogD) were correlated against HSA binding site characteristics, including hydrophobicity, hydrophilicity, enclosure, exposure, contact, site volume, and donor/acceptor ratio. Molecular descriptors nHD, TPSA, LogD, nHet, and MW were found to possess the most inherent capacities providing baseline information for the prediction of serum albumin binding site. We believe that these associations may form the bedrock for establishing a solid correlation between the physicochemical properties and Albumin binding site architecture. Information presented in this report would serve as critical in provisions of rational drug designing as well as drug delivery, bioavailability, and pharmacokinetics.
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Synthesis, characterization and antimicrobial analysis of metal-doped (Zn2+ and Ag+) brushite powder for bone regenerationBrushite, or Dicalcium phosphate dihydrate (CaHPO4⋅2H2O), is a well-known calcium phosphate (CaP) found in mineralized tissues and is utilized in medical treatment, particularly in bone powder for bone repair. Brushites with Zn2+ and Ag + ions concentration were synthesized in an aqueous solution using the conventional precipitation procedure. The synthesized brushites were characterized using techniques such as Fourier Transform Infrared Spectroscopy (FTIR), Powder X-ray diffraction (PXRD), Scanning Electron Microscopy (SEM), and bioassays were carried out to evaluate their antibacterial and antifungal activities. The alterations in PXRD and FTIR peak locations demonstrated that zinc and silver ions were effectively inserted into the brushite crystals. Initial tests revealed that the powders were innocuous, which make them potentially beneficial for mineralized tissue engineering. These brushites exhibited remarkable antimicrobial activities. Zn-doped brushite completely controlled the growth of fungi namely Macrophomina phaseolina and Sclerotium rolfsii at a concentration of 0.0039 mg mL-1 while Ag-doped brushite completely arrested the growth of these fungi at 0.0312 and 0.0039 mg mL-1, respectively. Likewise, both the brushite exhibited remarkable antibacterial activity against Bacillus thuringiensis and moderate activity against Escherichia coli. Brushite compounds coupled with active metal ions, notably Ag+ and Zn2+, demonstrated promise as a distinct class of reactive materials for bone-related applications.
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Cancer-specific glycosylation of CD13 impacts its detection and activity in preclinical cancer tissuesHarnessing the differences between cancer and non-cancer tissues presents new opportunities for selective targeting by anti-cancer drugs. CD13, a heavily glycosylated protein, is one example with significant unmetclinical potential in cancer drug discovery. Despite its high expression and activity in cancers, CD13 is also expressed in many normal tissues. Here, we report differential tissue glycosylation of CD13 across tissues and demonstrate for the first time that the nature and pattern of glycosylation of CD13 in preclinical cancer tissues are distinct compared to normal tissues. We identify cancer-specific O-glycosylation of CD13, which selectively blocks its detection in cancer models but not in normal tissues. In addition, the metabolism activity of cancer-expressed CD13 was observed to be critically dependent on its unique glycosylation. Thus, our data demonstrate the existence of discrete cancer-specific CD13 glycoforms and propose cancer-specific CD13 glycoforms as a clinically useful target for effective cancer-targeted therapy.
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Hypoxia-Responsive Prodrug of ATR Inhibitor, AZD6738, Selectively Eradicates Treatment-Resistant Cancer CellsTargeted therapy remains the future of anti-cancer drug development, owing to the lack of specificity of current treatments which lead to damage in healthy normal tissues. ATR inhibitors have in recent times demonstrated promising clinical potential, and are currently being evaluated in the clinic. However, despite the considerable optimism for clinical success of these inhibitors, reports of associated normal tissues toxicities remain a concern and can compromise their utility. Here, ICT10336 is reported, a newly developed hypoxia-responsive prodrug of ATR inhibitor, AZD6738, which is hypoxia-activated and specifically releases AZD6738 only in hypoxic conditions, in vitro. This hypoxia-selective release of AZD6738 inhibited ATR activation (T1989 and S428 phosphorylation) and subsequently abrogated HIF1a-mediated adaptation of hypoxic cancers cells, thus selectively inducing cell death in 2D and 3D cancer models. Importantly, in normal tissues, ICT10336 is demonstrated to be metabolically stable and less toxic to normal cells than its active parent agent, AZD6738. In addition, ICT10336 exhibited a superior and efficient multicellular penetration ability in 3D tumor models, and selectively eradicated cells at the hypoxic core compared to AZD6738. In summary, the preclinical data demonstrate a new strategy of tumor-targeted delivery of ATR inhibitors with significant potential of enhancing the therapeutic index.
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Unveiling the therapeutic potential: Evaluation of anti-inflammatory and antineoplastic activity of Magnolia champaca Linn’s stem bark isolate through molecular docking insightsMagnolia champaca Linn. has traditionally been used for medicinal activity in Asia for treating various chronic diseases as well as a source of food, medicines, and other commodities. Due to the long-used history of this plant, the present study was designed to explore the in vitro, in vivo and in silico anti-inflammatory and antineoplastic properties of the methanolic extract and fractions and the pure compound isolated from the most active chloroform fraction (CHF) of the stem bark of the plant. The isolated compound from the most active CHF was characterized and identified as a glycoside, trans-syringin, through chromatographic and spectroscopic (1H-NMR and 13C-NMR) analyses. In the in vitro anti-inflammatory assay, CHF was most effective in inhibiting inflammation and hemolysis of RBCs by 73.91 ± 1.70% and 75.92 ± 0.14%, respectively, induced by heat and hypotonicity compared to standard acetylsalicylic acid. In the egg albumin denaturation assay, CME and CHF showed the highest inhibition by 56.25 ± 0.82% and 65.82 ± 3.52%, respectively, contrasted with acetylsalicylic acid by 80.14 ± 2.44%. In an in vivo anti-inflammatory assay, statistically significant (p < 0.05) decreases in the parameters of inflammation, such as paw edema, leukocyte migration and vascular permeability, were recorded in a dose-dependent manner in the treated groups. In the antineoplastic assay, 45.26 ± 2.24% and 68.31 ± 3.26% inhibition of tumor cell growth for pure compound were observed compared to 73.26 ± 3.41% for standard vincristine. Apoptotic morphologic alterations, such as membrane and nuclear condensation and fragmentation, were also found in EAC cells after treatment with the isolated bioactive pure compound. Such treatment also reversed the increased WBC count and decreased RBC count to normal values compared to the untreated EAC cell-bearing mice and the standard vincristine-treated mice. Subsequently, in silico molecular docking studies substantiated the current findings, and the isolated pure compound and standard vincristine exhibited −6.4 kcal/mol and −7.3 kcal/mol binding affinities with topoisomerase-II. Additionally, isolated pure compound and standard diclofenac showed −8.2 kcal/mol and −7.6 kcal/mol binding affinities with the COX-2 enzyme, respectively. The analysis of this research suggests that the isolated bioactive pure compound possesses moderate to potent anti-inflammatory and antineoplastic activity and justifies the traditional uses of the stem bark of M. champaca. However, further investigations are necessary to analyze its bioactivity, proper mechanism of action and clinical trials for the revelation of new drug formulations.
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Management of COPD and Comorbidities in COPD patients by Dispensing Pharmaceutical Care following Global Initiative for chronic Obstructive Lung Disease-Guidelines (GOLD guidelines 2020): A study protocol for a Prospective Randomized Clinical TrialCOPD (chronic obstructive pulmonary disease) is a medical condition that encompasses several chronic, progressive, and severe respiratory illnesses, such as emphysema and chronic bronchitis. COPD is the 4th most deadly disease in the world and its prevalence is expected to increase. Despite the abundance of information on the disease’s etiology, pathophysiology, and treatment possibilities, it has long been underdiagnosed and underreported for a long time, particularly in developing countries. The symptoms of COPD result in significant impairments and significant impact on quality of life. COPD is the third leading cause of death in Pakistan. According to the published literature, COPD has been found to be associated with a serious economic burden, either the direct cost to healthcare systems in the form of frequent hospital admissions or indirect costs to patients suffering from COPD. Despite the availability of excellent medication, COPD treatment goals are frequently not achieved resulting in poor management of COPD. The recent studies revealed that due to the missing role of Pharmacists in most of the public sector hospitals of Pakistan, the COPD disease management protocols are not being properly followed. Pharmacists can help the healthcare system by implementing these management protocols that focus on patient education about the disease, prescribed medications, and proper inhalation techniques. Furthermore, the pharmacists as an effective healthcare’s team member properly educate the patients about the ongoing assessments and their willingness to follow treatment.
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Winds of change: urgent challenges and emerging opportunities in submerged prehistory, a perspective from the North SeaDevelopment of the continental shelf has accelerated significantly as nations around the world seek to harness offshore renewable energy. Many areas marked for development align with submerged palaeolandscapes. Poorly understood and difficult to protect, these vulnerable, prehistoric landscapes provide specific challenges for heritage management. Indeed, there now appears to be a schism between what underwater cultural heritage policy intends and what it is achieving in practice. Shortcomings in international and national legislature ensure that large parts of the continental shelf, including areas under development, may have little or no legal protection. Increasingly impacted by extensive development, these unique cultural landscapes are ever more at risk. However, heritage challenges posed by such development also create opportunities. An immense amount of data is being generated by development, and there is an opportunity to establish broader cooperative relationships involving industrial stakeholders, national curators, government bodies, and heritage professionals. As a matter of urgency, the archaeological community must better engage with the offshore sector and development process. If achieved, we may revolutionise our knowledge of submerged prehistoric settlement and land use. Otherwise, our capacity to reconstruct prehistoric settlement patterns, learn from past climate change, or simply manage what are among the best-preserved postglacial landscapes globally may be irreparably undermined.
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On the Versatility of the sp-, sp2‑, and sp3‑Hybridized Chalcogen-Bearing Molecules To Engage in Type I Chalcogen···Chalcogen Interactions: A Quantum Mechanical Investigation of Like···Like and Unlike ComplexesThe predilection of sp-, sp2-, and sp3-hybridized chalcogen-bearing molecules to engage in type I chalcogen···chalcogen interactions was comparatively unveiled in like···like/unlike CY···YC, YCY···YCY, and F2Y···YF2 (where Y = O, S, and Se) complexes, respectively. Upon the optimized monomers, a potential energy surface (PES) scan was conducted to pinpoint the most favorable complexes. The energetic findings unveiled the ability of the investigated systems to engage in the interactions under study with binding energy values ranging from −0.36 to −2.33 kcal/mol. Notably, binding energies were disclosed to align in the posterior sequence; sp2- (i.e., YCY···YCY) > sp- (i.e., CY···YC) > sp3- (i.e., F2Y···YF2) hybridized complexes, except the like···like oxygen-bearing complexes. Instead, the highest negative binding energy values were detected for the OCO···OCO followed by those of the F2O···OF2 and CO···OC complexes. Furthermore, the like···like selenium-bearing complexes demonstrated the most considerable binding energies compared to the other investigated complexes. Remarkably, the quantum theory of atoms in molecules and noncovalent interaction index analyses revealed the highly directional and closed-shell nature of the investigated chalcogen···chalcogen interactions. Symmetry adapted-perturbation theory findings outlined the dispersion forces as the commanding forces for all the studied complexes. These observations will provide convincing justifications for the nature of chalcogens within type I chalcogen···chalcogen interactions, leading to increased progress in various domains regarding drug design and materials science.
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Biodegradable polymer‐metal‐organic framework (MOF) composites for controlled and sustainable pesticide deliveryDue to high surface area, loading capacity, and selectivity, Metal-Organic Frameworks (MOFs) have shown much promise recently for potential applications in extraction and delivery of agrochemicals for environmental remediation and sustainable release, respectively. However, application of MOFs for pesticide delivery in wider agricultural context can be restricted by their granular form. Herein, an alternative approach is studied using biodegradable polymer-MOF composites to address this limitation. The loading and release of a widely used pesticide, 2,4-dichloropheoxycetic acid (2,4-D), is studied using two MOFs, UiO-66 and UiO-66-NH2, and the 2,4-D-loaded MOFs are incorporated into biodegradable polycaprolactone composites for convenient handling and minimizing runoff. The MOFs are loaded by in-situ, and post-synthetic methods, and characterised thoroughly to ensure successful synthesis and loading of 2,4-D. The pesticide release studies are performed on the MOFs and composites in distilled water, and analysed using UV-Vis spectroscopy, demonstrating sustained-release of 2,4-D over 16 days. The loaded MOF samples show high loading capacity, with up to 45 wt% for the in-situ loaded UiO-66. Release kinetics show more sustained release of 2,4-D from UiO-66-NH2 compared to UiO-66, which can be due to supramolecular interactions between the NH2 group of UiO-66-NH2 and 2,4-D. This is further supported by computational studies.
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Beneficial Effects of Natural Alkaloids from Berberis glaucocarpa as Antidiabetic Agents: An In Vitro, In Silico, and In Vivo ApproachDiabetes, also known as diabetes mellitus (DM), is a metabolic disorder characterized by an abnormal rise in blood sugar (glucose) levels brought on by a complete or partial lack of insulin secretion along with corresponding changes in the metabolism of lipids, proteins, and carbohydrates. It has been reported that medicinal plants play a pivotal role in the treatment of various ailments such as diabetes mellitus, dyslipidemia, and hypertension. The current study involved exploring the acute toxicity and in vivo antidiabetic activity of berberine (WA1), palmatine (WA2), and 8- trichloromethyl dihydroberberine (WA3) previously isolated from Berberis glaucocarpa Stapf using a streptozotocin (STZ)-induced diabetic rat model. Body weight and blood glucose level were assessed on a day interval for 4 weeks. Biochemical parameters, antioxidant enzymes, and oxidative stress markers were also determined. In an acute toxicity profile, the WA1, WA2, and WA3 were determined to be nontoxic up to 500 mg/kg (b.w). After the second and third weeks of treatment (14 and 21 days), the blood glucose levels in the WA1-, WA2-, and WA3-treated groups were significantly lower than those in the diabetic control group (476.81 ± 8.65 mg/dL, n = 8, P < 0.001). On the 21st day, there was a decrease in the blood glucose level and the results obtained were 176.33 ± 4.69, 197.21 ± 4.80, and 161.99 ± 4.75 mg/dL (n = 8, P < 0.001) for WA1, WA2, and WA3 at 12 mg/kg, respectively, as opposed to the diabetic control group (482.87 ± 7.11 mg/dL, n = 8, P < 0.001). Upon comparison with the diabetic group at the end of the study (28 days), a substantial drop in the glucose level of WA3 at 12 mg/kg (110.56 ± 4.11 mg/dL, n = 8, P < 0.001) was observed that was almost near the values of the normal control group. The treated groups (WA1, WA2, and WA3) treated with the samples displayed a significant decline in the levels of HbA1c. Treatment of the samples dramatically lowered the lipid level profile. In groups treated with samples, plasma levels of triglycerides, total cholesterol, and LDL were significantly lowered [F (5, 42) = 100.6, n = 8, P < 0.001]; these levels were also significantly decreased [F (5, 42) = 129.6 and 91.17, n = 8, P < 0.001]. In contrast to the diabetes group, all treated groups had significantly higher HDL levels [F (5, 42) = 15.46, n = 8, P < 0.001]. As a result, hypolipidemic activity was anticipated in the samples. In addition to that, the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) was considerably elevated in the groups treated with the sample compared to the diabetic control group (n = 8, P < 0.001).
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Crystal or Glass? Chemical and Crystallographic Factors in the Amorphization of Molecular MaterialsThe creation of long-lived amorphous phases has potential applications in numerous fields; for example, the instability of the amorphous phase leads to higher solubility of pharmaceutical phases, often leading to higher bioavailability. The rate of recrystallization of an amorphous phase poses a significant limitation to the application of many such phases; however, understanding the energetic and structural factors that control the stability of molecular amorphous phases is limited by empirical classifications based on thermal analysis used to identify materials. From a set of molecularly related benzanilides, examples of all three classes have been identified, allowing use of crystal structural analysis, Raman spectroscopy, and energetic calculations to determine the structural factors playing a role in the different stabilities. While the behavior of most systems reflects the relative energy of the crystalline phase to the amorphous phase, kinetic factors based on whether a NH···O=C hydrogen bond is present in the crystalline phase play a key role in stabilizing the amorphous phase as the loss of this bond reduces the conversion rate. In contrast, systems without this bond display fast recrystallization due to the greater structural similarity between the amorphous and crystalline phases.
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In Vitro and in Vivo Evaluation Of Pharmacological Activites of Pouzolzia SanguineaPouzolzia sanguinea grows in tropical and sub-tropical regions of Bangladesh, used for a variety of purposes including pain, rheumatoid kidney diseases in traditional medicine. The crude ethanolic leaf extract of P. sanguinea with its different fractions (ethanol, n-hexane, and chloroform) was investigated for phytochemical constituents, in vitro antioxidant, anti-inflammatory effects, in-vivo analgesic and antipyretic activities. Preliminary phytochemical constituents were identified by chemical group test. P. sanguinea fractionated extracts contain alkaloids, glycosides, tannins, flavonoids, saponins, gums, and amides. Antioxidant activity test was performed by both qualitative (TLC and Rf value) and quantitative tests (inhibition of DPPH free radical scavenging). Extracts exhibited significant (p <0.001, p <0.0001) inhibition of DPPH free radical scavenging activity as compared to the standard drug ascorbic acid at similar doses. In vitro anti-inflammatory activity was determined by protein denaturation of egg albumin method. The percent inhibition of protein denaturation in the experiment of ethanol extract was found significantly higher (p <0.0001) compared with chloroform and n-hexane extracts. In addition, in vivo analgesic and antipyretic effects were determined in mice by acetic acid-induced writhing and yeast-induced pyrexia methods. The ethanol extracts of P. sanguinea exhibited inhibition of writhing reflex on mice by 71.58% at the dose of 500 mg/kg body weight which had greater analgesic activity than other n-hexane and chloroform extracts. In the anti-pyretic test, fractional extracts ethanol, chloroform, and n-hexane at a dose of 500 mg/kg body weight significantly (p <0.05) decreased pyrexia in mice up to 3 h as compared with the positive control paracetamol drug at a dose of 150 mg/kg body weight. In our in vitro and in vivo study models, it is evident that Pouzolzia sanguinea fractionated extracts showed significant antioxidant, anti-inflammatory, analgesic, and antipyretic activities.
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Photophysical, thermal and imaging studies on vancomycin functional branched poly(N-isopropyl acrylamide) of differing degrees of branching containing nile red for detection of Gram-positive bacteriaHighly branched poly(N-isopropyl acrylamide) additives chain end functionalised with vancomycin have been designed to agglutinate and report on targetted Gram-positive strains of bacteria (S. aureus). These branched systems selectively desolvate with temperature or binding interactions depending on their chain architecture. We have prepared samples with three different degrees of branching which have incorporated Nile red acrylate as a low concentration of co-monomer to report upon their solution properties. A linear analogue polymer functionalised with vancomycin along the chain instead of the termini is presented as a control which does not bind to targeted bacteria. These samples were analysed by diffusion NMR spectrometry (DOSY), calorimetry, fluorescence lifetime measurements, optical microscopy and scanning electron microscopy to gain a full understanding of their solution properties. The branched polymers are shown conclusively to have a core-shell structure, where the chain ends are expressed from the desolvated globule even above the lower critical solution temperature – as demonstrated by NMR measurements. The level of desolvation is critically dependent on the degree of branching, and as a result we have found intermediate structures provide optimal body temperature bacterial sensing as a consequence of the Nile red reporting dye.
