Asparagus officinalis Herb-derived Carbon Quantum Dots: Luminescent Probe for Medical Diagnostics.

The utilization of natural materials for the synthesis of highly fluorescent carbon quantum dots (CQDs) presents a sustainable approach to overcome the challenges associated with traditional chemical precursors. Here, we report the synthesis of novel S,N-self-doped CQDs (S,N@CQDs) derived from asparagus officinalis herb. These S,N@CQDs exhibit 16.7% fluorescence quantum yield, demonstrating their potential in medical diagnostics. We demonstrate the efficacy of S,N@CQDs as luminescent probes for the detection of anti-pathogenic medications metronidazole (MTZ) and nitazoxanide (NTZ) over concentration ranges of 0.0-180.0 µM (with a limit of detection (LOD) of 0.064 µM) and 0.25-40.0 µM (LOD of 0.05 µM), respectively. The probes were successfully applied to determine MTZ and NTZ in medicinal samples, real samples, and spiked human plasma, with excellent recovery rates ranging from 99.82% to 103.03%. Additionally, S,N@CQDs demonstrate exceptional efficacy as diagnostic luminescent probes for hemoglobin (Hb) detection over a concentration range of 0-900 nM, with a minimal detectability of 9.24 nM, comparable to commercially available medical laboratory diagnostic tests. The eco-friendly synthesis and precise detection limits of S,N@CQDs meet necessary analytical requirements and hold promise for advancing diagnostic capabilities in clinical settings. This research signifies a significant step towards sustainable and efficient fluorescence-based medical diagnostics.

Chronic testosterone deficiency increases late inward sodium current and promotes triggered activity in ventricular myocytes from aging male mice.

Clinical studies suggest low testosterone levels are associated with cardiac arrhythmias, especially in later life. We investigated whether chronic exposure to low circulating testosterone promoted maladaptive electrical remodeling in ventricular myocytes from aging male mice and determined the role of late inward sodium current (INa,L) in this remodeling. C57BL/6 mice had a gonadectomy (GDX) or sham surgery (1 mo) and were aged to 22-28 mo. Ventricular myocytes were isolated; transmembrane voltage and currents were recorded (37°C). Action potential duration at 70 and 90% repolarization (APD70 and APD90) was prolonged in GDX compared with sham myocytes (APD90, 96.9 ± 3.2 vs. 55.4 ± 2.0 ms; P < 0.001). INa,L was also larger in GDX than sham (-2.4 ± 0.4 vs. -1.2 ± 0.2 pA/pF; P = 0.002). When cells were exposed to the INa,L antagonist ranolazine (10 µM), INa,L declined in GDX cells (-1.9 ± 0.5 vs. -0.4 ± 0.2 pA/pF; P < 0.001) and APD90 was reduced (96.3 ± 14.8 vs. 49.2 ± 9.4 ms; P = 0.001). GDX cells had more triggered activity (early/delayed afterdepolarizations, EADs/DADs) and spontaneous activity than sham. EADs were inhibited by ranolazine in GDX cells. The selective NaV1.8 blocker A-803467 (30 nM) also reduced INa,L, decreased APD and abolished triggered activity in GDX cells. Scn5a (NaV1.5) and Scn10a (NaV1.8) mRNA was increased in GDX ventricles, but only NaV1.8 protein abundance was increased in GDX compared with sham. In vivo studies showed QT prolongation and more arrhythmias in GDX mice. Thus, triggered activity in ventricular myocytes from aging male mice with long-term testosterone deficiency arises from APD prolongation mediated by larger NaV1.8- and NaV1.5-associated currents, which may explain the increase in arrhythmias.NEW & NOTEWORTHY Older men with low testosterone levels are at increased risk of developing cardiac arrhythmias. We found aged mice chronically exposed to low testosterone had more arrhythmias and ventricular myocytes had prolonged repolarization, abnormal electrical activity, larger late sodium currents, and increased expression of NaV1.8 sodium channels. Drugs that inhibit late sodium current or NaV1.8 channels abolished abnormal electrical activity and shortened repolarization. This suggests the late sodium current may be a novel target to treat arrhythmias in older testosterone-deficient men.

Recent Advances in Nanomechanical Measurements and Their Application for Pharmaceutical Crystals.

Mechanical behavior of pharmaceutical crystals directly impacts the formulation development and manufacturing of drug products. The understanding of crystal structure-mechanical behavior of pharmaceutical and molecular crystals has recently gained substantial attention among pharmaceutical and materials scientists with the advent of advanced nanomechanical testing instruments like nanoindentation. For the past few decades, instrumented nanoindentation was a popular technique for measuring the mechanical properties of thin films and small-length scale materials. More recently it is being implemented to investigate the mechanical properties of pharmaceutical crystals. Integration of correlative microscopy techniques and environmental control opened the door for advanced structure-property correlation under processing conditions. Preventing the degradation of active pharmaceutical ingredients from external factors such as humidity, temperature, or pressure is important during processing. This review deals with the recent developments in the synchronized nanomechanical measurements of pharmaceutical crystals toward the fast and effective development of high-quality pharmaceutical drug products. This review also summarizes some recent reports to intensify how one can design and control the nanomechanical properties of pharmaceutical solids. Measurement challenges and the scope for studying nanomechanical properties of pharmaceutical crystals using nanoindentation as a function of crystal structure and in turn to develop fundamental knowledge in the structure-property relationship with the implications for drug manufacturing and development are discussed in this review. This review further highlights recently developed capabilities in nanoindentation, for example, variable temperature nanoindentation testing, in situ imaging of the indented volume, and nanoindentation coupled Raman spectroscopy that can offer new quantitative details on nanomechanical behavior of crystals and will play a decisive role in the development of coherent theories for nanomechanical study of pharmaceutical crystal.

Crystallographic evidence of Watson-Crick connectivity in the base pair of anionic adenine with thymine.

Utilizing an ionic liquid strategy, we report crystal structures of salts of free anionic nucleobases and base pairs previously studied only computationally and in the gas phase. Reaction of tetrabutylammonium ([N4444]+) or tetrabutylphosphonium ([P4444]+) hydroxide with adenine (HAd) and thymine (HThy) led to hydrated salts of deprotonated adenine, [N4444][Ad]·2H2O, and thymine, [P4444][Thy]·2H2O, as well as the double salt cocrystal, [P4444]2[Ad][Thy]·3H2O·2HThy. The cocrystal includes the anionic [Ad-(HThy)] base pair which is a stable formation in the solid state that has previously not even been suggested. It exhibits Watson-Crick connectivity as found in DNA but which is unusual for the free neutral base pairs. The stability of the observed anionic bases and their supramolecular formations and hydrates has also been examined by electronic structure calculations, contributing to more insight into how base pairs can bind when a proton is removed and highlighting mechanisms of stabilization or chemical transformation in the DNA chains.

Runx proteins mediate protective immunity against Leishmania donovani infection by promoting CD40 expression on dendritic cells.

The level of CD40 expression on dendritic cells (DCs) plays a decisive role in disease protection during Leishmania donovani (LD) infection. However, current understanding of the molecular regulation of CD40 expression remains elusive. Using molecular, cellular and functional approaches, we identified a role for Runx1 and Runx3 transcription factors in the regulation of CD40 expression in DCs. In response to lipopolysaccharide (LPS), tumor necrosis factor alpha (TNFα) or antileishmanial drug sodium antimony gluconate (SAG), both Runx1 and Runx3 translocated to the nucleus, bound to the CD40 promoter and upregulated CD40 expression on DCs. These activities of Runx proteins were mediated by the upstream phosphatidylinositol 3-kinase (PI3K)-Akt pathway. Notably, LD infection attenuated LPS- or TNFα-induced CD40 expression in DCs by inhibiting PI3K-Akt-Runx axis via protein tyrosine phosphatase SHP-1. In contrast, CD40 expression induced by SAG was unaffected by LD infection, as SAG by blocking LD-induced SHP-1 activation potentiated PI3K-Akt signaling to drive Runx-mediated CD40 upregulation. Adoptive transfer experiments further showed that Runx1 and Runx3 play a pivotal role in eliciting antileishmanial immune response of SAG-treated DCs in vivo by promoting CD40-mediated type-1 T cell responses. Importantly, antimony-resistant LD suppressed SAG-induced CD40 upregulation on DCs by blocking the PI3K-Akt-Runx pathway through sustained SHP-1 activation. These findings unveil an immunoregulatory role for Runx proteins during LD infection.

Multidrug efflux transporter ABCG2: expression and regulation.

The adenosine triphosphate (ATP)-binding cassette efflux transporter G2 (ABCG2) was originally discovered in a multidrug-resistant breast cancer cell line. Studies in the past have expanded the understanding of its role in physiology, disease pathology and drug resistance. With a widely distributed expression across different cell types, ABCG2 plays a central role in ATP-dependent efflux of a vast range of endogenous and exogenous molecules, thereby maintaining cellular homeostasis and providing tissue protection against xenobiotic insults. However, ABCG2 expression is subjected to alterations under various pathophysiological conditions such as inflammation, infection, tissue injury, disease pathology and in response to xenobiotics and endobiotics. These changes may interfere with the bioavailability of therapeutic substrate drugs conferring drug resistance and in certain cases worsen the pathophysiological state aggravating its severity. Considering the crucial role of ABCG2 in normal physiology, therapeutic interventions directly targeting the transporter function may produce serious side effects. Therefore, modulation of transporter regulation instead of inhibiting the transporter itself will allow subtle changes in ABCG2 activity. This requires a thorough comprehension of diverse factors and complex signaling pathways (Kinases, Wnt/ß-catenin, Sonic hedgehog) operating at multiple regulatory levels dictating ABCG2 expression and activity. This review features a background on the physiological role of transporter, factors that modulate ABCG2 levels and highlights various signaling pathways, molecular mechanisms and genetic polymorphisms in ABCG2 regulation. This understanding will aid in identifying potential molecular targets for therapeutic interventions to overcome ABCG2-mediated multidrug resistance (MDR) and to manage ABCG2-related pathophysiology.

Molecular Mechanisms of Cellular Injury and Role of Toxic Heavy Metals in Chronic Kidney Disease.

Chronic kidney disease (CKD) is a progressive disease that affects millions of adults every year. Major risk factors include diabetes, hypertension, and obesity, which affect millions of adults worldwide. CKD is characterized by cellular injury followed by permanent loss of functional nephrons. As injured cells die and nephrons become sclerotic, remaining healthy nephrons attempt to compensate by undergoing various structural, molecular, and functional changes. While these changes are designed to maintain appropriate renal function, they may lead to additional cellular injury and progression of disease. As CKD progresses and filtration decreases, the ability to eliminate metabolic wastes and environmental toxicants declines. The inability to eliminate environmental toxicants such as arsenic, cadmium, and mercury may contribute to cellular injury and enhance the progression of CKD. The present review describes major molecular alterations that contribute to the pathogenesis of CKD and the effects of arsenic, cadmium, and mercury on the progression of CKD.

Catalytic Enantioselective Synthesis of Aryl-Methyl Organophosphorus Compounds.

A catalytic enantioselective protocol for the synthesis of aryl-methyl organophosphorus compounds is reported. Utilizing a chiral phosphoric acid as a catalyst, a wide range of indole derivatives reacted with phosphorylated quinomethanes in high yield with excellent enantioselectivity. This is the first report on the application of phosphorylated quinomethanes in asymmetric synthesis.

Insights into Structural Modifications of Valproic Acid and Their Pharmacological Profile.

Valproic acid (VPA) is a well-established anticonvulsant drug discovered serendipitously and marketed for the treatment of epilepsy, migraine, bipolar disorder and neuropathic pain. Apart from this, VPA has potential therapeutic applications in other central nervous system (CNS) disorders and in various cancer types. Since the discovery of its anticonvulsant activity, substantial efforts have been made to develop structural analogues and derivatives in an attempt to increase potency and decrease adverse side effects, the most significant being teratogenicity and hepatotoxicity. Most of these compounds have shown reduced toxicity with improved potency. The simple structure of VPA offers a great advantage to its modification. This review briefly discusses the pharmacology and molecular targets of VPA. The article then elaborates on the structural modifications in VPA including amide-derivatives, acid and cyclic analogues, urea derivatives and pro-drugs, and compares their pharmacological profile with that of the parent molecule. The current challenges for the clinical use of these derivatives are also discussed. The review is expected to provide necessary knowledgebase for the further development of VPA-derived compounds.

Crystallographic and Energetic Insights into Reduced Dissolution and Physical Stability of a Drug-Surfactant Salt: The Case of Norfloxacin Lauryl Sulfate.

A commonly used pharmaceutical surfactant, sodium lauryl sulfate (SLS), has been reported to reduce the dissolution rate of drugs due to the formation of a less soluble drug-lauryl sulfate salt. In this study, we provide direct crystallographic evidence of the formation of salt between SLS and norfloxacin (NOR), [NORH+][LS-]·1.5 H2O. The available crystal structure also enables the use of the energy framework to gain an understanding of the structure-property relationship. Results show that the hydrophobic methyl groups in SLS dominate the surfaces of the [NORH+][LS-]·1.5 H2O crystals, resulting in the increased hydrophobicity and reduced wettability by aqueous media. Moreover, an analysis of molecular environments and energy calculations of water molecules provides insight into the stability of [NORH+][LS-]·1.5 H2O with variations in the relative humidity and temperature. In summary, important pharmaceutical properties, such as solubility, dissolution, and thermal stability, of the drug-surfactant salt [NORH+][LS-]·1.5 H2O have been characterized and understood based on crystallographic and energetic analyses of the crystal structure.

Forcing Dicyanamide Coordination to f-Elements by Dissolution in Dicyanamide-Based Ionic Liquids.

A robust general route to lanthanide dicyanamide (DCA-) complexes has been developed where f-element salts are dissolved in DCA--based ionic liquids (ILs) directly or formed in situ, forcing coordination of these normally weakly coordinating soft N-donor anions, even in an ambient, non-moisture-excluding environment. A series of lanthanide complexes [C2mim][Ln(DCA)4(H2O)4] (C2mim = 1-ethyl-3-methylimidazolium; Ln = La, Nd, Eu, Tb, Dy, and Yb) and [C2mim]3n[La(OH2)4(µ2-DCA)4]n[La(OH2)2(µ3-DCA)3(µ2-DCA)4]2n(Cl)4n were crystallized under a variety of conditions using this methodology and structurally characterized using single crystal X-ray diffraction. Although not all examples were isostructural, the dominant feature across the series was the presence of [Ln(DCA)4(H2O)4]- anionic nodes with all terminal DCA- ligands accepting hydrogen bonds from the coordinated water molecules forming a 3D metal organic framework. To determine if any structural clues might aid in the further development of the synthetic methodology, the metal-free IL [C1mim][DCA] (C1mim = 1,3-dimethylimidazolium), a room-temperature solid, crystalline analogue of the reaction IL, which is liquid at room temperature, was also prepared and structurally characterized. The ready isolation of these compounds allowed us to begin an investigation of the physical properties such as the luminescence at room and low temperatures for the Eu, Tb, and Dy representatives.

Thermoluminescence Studies of ß and γ-Irradiated Geological Materials for Environment Monitoring.

In the present report, thermally stimulated luminescence (TSL) of quartz and limestone samples irradiated with ß and γ-rays has been investigated. Herein the formation of trap depths and calculation of kinetic parameters of ß and γ - irradiated quartz and limestone samples were studied through thermoluminescence (TL) glow curve analyses. The quartz and limestone samples were collected from various sites of Chhattisgarh (Patharia and Dalli-Rajhara mines). The collected raw samples were annealed at 400 °C. The phase formation of collected samples is confirmed by X-ray diffraction studies. The grain sizes of the samples are determined by using Debye-Scherrer formula. TL glow curves of the collected samples were recorded for various doses of ß and γ-rays. Kinetic parameters such as order of kinetics frequency factor and trap depth were calculated by employing CGCD methods. A comparative study on the TL properties of the geological materials under ß and γ-irradiation was done. The trap model analysis was executed to determine the nature of traps responsible for dominant TL peaks of ß and γ-irradiated limestone and quartz samples.

From Molecules to Interactions to Crystal Engineering: Mechanical Properties of Organic Solids.

Mechanical properties of organic molecular crystals have been noted and studied over the years but the complexity of the subject and its relationship with diverse fields such as mechanochemistry, phase transformations, polymorphism, and chemical, mechanical, and materials engineering have slowed understanding. Any such understanding also needs conceptual advances-sophisticated instrumentation, computational modeling, and chemical insight-lack of such synergy has surely hindered progress in this important field. This Account describes our efforts at focusing down into this interesting subject from the viewpoint of crystal engineering, which is the synthesis and design of functional molecular solids. Mechanical properties of soft molecular crystals imply molecular movement within the solid; the type of property depends on the likelihood of such movement in relation to the applied stress, including the ability of molecules to restore themselves to their original positions when the stress is removed. Therefore, one is interested in properties such as elasticity, plasticity, and brittleness, which are linked to structural anisotropy and the degree to which a structure veers toward isotropic character. However, these matters are still by no means settled and are system dependent. While elasticity and brittleness are probably displayed by all molecular solids, the window of plasticity is perhaps the one that is most amenable to crystal engineering strategies and methods. In all this, one needs to note that mechanical properties have a kinetic component: a crystal that is elastic under slow stress application may become plastic or brittle if the same stress is applied quickly. In this context, nanoindentation studies have shown themselves to be of invaluable importance in understanding structural anisotropy. Several problems in solid state chemistry, including classical ones, such as the melting point alternation in aliphatic straight chain dicarboxylic acids and hardness modulation in solid solutions, have been understood more clearly with this technique. The way may even be open to picoindentation studies and the observation of molecular level movements. As in all types of crystal engineering, an understanding of the intermolecular interactions can lead to property oriented crystal design, and we present examples where complex properties may be deliberately turned on or off in organic crystals: one essentially fine-tunes the degree of isotropy/anisotropy by modulating interactions such as hydrogen bonding, halogen bonding, π···π interactions, and C-H···π interactions. The field is now wide open as is attested by the activities of several research groups working in the area. It is set to take off into the domains of smart materials, soft crystals, and superelasticity and a full understanding of solid state reactivity.

Improving the sensitivity of traditional Western blotting via Streptavidin containing Poly-horseradish peroxidase (PolyHRP).

Immunoassays such as ELISAs and Western blotting have been the common choice for protein validation studies for the past several decades. Technical advancements and modifications are continuously being developed to enhance the detection sensitivity of these procedures. Among them, Streptavidin-containing poly-horseradish peroxidase (PolyHRP) based detection strategies have been shown to improve signals in ELISA. The use of commercially available Streptavidin and antibodies conjugated with many HRPs (PolyHRPs) to potentially enhance the detection sensitivity in Western blotting has not been previously investigated in a comprehensive manner. The use of PolyHRP-secondary antibody instead of HRP-secondary antibody increased the Western blotting sensitivity up to 85% depending on the primary antibody used. The use of a biotinylated secondary antibody and commercially available Streptavidin-conjugated with HRP or PolyHRP all resulted in increased sensitivity with respect to antigen detection. Utilizing a biotinylated secondary antibody and Streptavidin-conjugated PolyHRP resulted in as much as a 110-fold increase in Western blotting sensitivity over traditional Western blotting methods. Quantification of troponin I in rat heart lysates showed that the traditional Western blotting method only detected troponin I in ≥2 µg of lysate while Streptavidin-conjugated PolyHRP20 detected troponin I in ≥50 ng of lysate. A modified blocking procedure is also described that eliminated the interference caused by the endogenous biotinylated proteins. These results suggest that Streptavidin-conjugated PolyHRP and PolyHRP secondary antibodies are likely to be commonly utilized for Western blots in the future.

Crystallographic Insights into the Behavior of Highly Acidic Metal Cations in Ionic Liquids from Reactions of Titanium Tetrachloride with [1-Butyl-3-Methylimidazolium][X] Ionic Liquids (X = Chloride, Bromide, Tetrafluoroborate).

Highly charged metal ions are difficult to investigate in weakly coordinating ionic liquids (ILs) because of the insolubility of their solid forms, but the molecular liquid TiCl4 offers a way to react tetravalent metal ions in an IL. Reactions of TiCl4 with 1-butyl-3-methylimidazolium ([C4mim]+)-based ILs containing chloride or bromide lead to mixtures of highly metastable amorphous solids and small amounts of crystalline chlorotitanate salts including [C4mim]2[TiCl6] and two polymorphs of [C4mim]2[Ti2Cl10] in a manner not well correlated with stoichiometry or anion identity. The reaction of TiCl4 with [C4mim][BF4] yields crystals of the mixed fluoro-chloro complex [C4mim]2[Ti4F6Cl12], indicating spontaneous reaction of the IL ions to generate HF in situ. These unusual behaviors are explained in terms of the exceptionally high acidity of Ti4+ and the unusual behavior of TiCl4 among metal halides as a nonpolar molecular compound.

Hydrophobic Inorganic Oxide Pigments via Polymethylhydrosiloxane Grafting: Dispersion in Aqueous Solution at Extraordinarily High Solids Concentrations.

Building on the recent demonstration of aqueous-dispersible hydrophobic pigments that retain their surface hydrophobicity even after drying, we demonstrate the synthesis of surface-modified Ti-Pure R-706 (denoted R706) titanium dioxide-based pigments, consisting of a thin (one to three monolayers) grafted polymethylhydrosiloxane (PMHS) coating, which (i) are hydrophobic in the dry state according to capillary rise and dynamic vapor sorption measurements and (ii) form stable aqueous dispersions at solid contents exceeding 75 wt % (43 vol %), without added dispersant, displaying similar rheology to R706 native oxide pigments at 70 wt % (37 vol %) consisting of an optimal amount of conventional polyanionic dispersant (0.3 wt % on pigment basis). The surface-modified pigments have been characterized via 29Si and 13C cross-polarization/magic angle spinning solid-state NMR spectroscopy; infrared spectroscopy; thermogravimetric and elemental analyses; and ζ potential measurements. On the basis of these data, the stability of the surface-modified PMHS-R706 aqueous dispersions is attributed to steric effects, as a result of grafted PMHS strands on the R706 surface, and depends on the chaotropic nature of the base used during PMHS condensation to the pigment/polysiloxane interface. The lack of water wettability of the surface-modified oxide particles in their dry state translates to improved water-barrier properties in coatings produced with these surface-modified pigment particles. The synthetic approach appears general as demonstrated by its application to various inorganic-oxide pigment particles.

Continue, adjust, or stop antipsychotic medication: developing and user testing an encounter decision aid for people with first-episode and long-term psychosis.

BACKGROUND: People with psychosis struggle with decisions about their use of antipsychotics. They often want to reduce the dose or stop, while facing uncertainty regarding the effects these decisions will have on their treatment and recovery. They may also fear raising this issue with clinicians. The purpose of this study was to develop and test a shared decision making (SDM) tool to support patients and clinicians in making decisions about antipsychotics. METHODS: A diverse editorial research team developed an Encounter Decision Aid (EDA) for patients and clinicians to use as part of the psychiatric consultation. The EDA was tested using 24 semistructured interviews with participants representing six stakeholder groups: patients with first-episode psychosis, patients with long-term psychosis, family members, psychiatrists, mental health counselors, and administrators. We used inductive and deductive coding of interview transcripts to identify points to revise within three domains: general impression and purpose of the EDA; suggested changes to the content, wording, and appearance; and usability and potential contribution to the psychiatric consultation. RESULTS: An EDA was developed in an iterative process that yielded evidence-based answers to five frequently asked questions about antipsychotic medications. Patients with long-term psychosis and mental health counselors suggested more changes and revisions than patients with first-episode psychosis and psychiatrists. Family members suggested more revisions to the answers about potential risks of stopping or adjusting antipsychotics than other respondents. CONCLUSIONS: The EDA was perceived as potentially useful and feasible in psychiatric routine care, especially if presented during the consultation.

Recommendations from the Salzburg Global Seminar on Rethinking Care Toward the End of Life.

OBJECTIVE: In December 2016, 66 health leaders from 14 countries convened at the Salzburg Global Seminar (SGS) to engage in cross-cultural and collaborative discussions centered on 'Rethinking Care Toward the End of Life'. Conversations focused on global perspectives on death and dying, challenges experienced by researchers, physicians, patients and family caregivers. This paper summarizes key findings and recommendations from SGS. DESIGN: Featured sessions focused on critical issues of end of life care led by key stakeholders, physicians, researchers, and other global leaders in palliative care. Sessions spanned across several critical themes including: patient/family/caregiver engagement, integrating health and community-based social care, eliciting and honoring patient preferences, building an evidence base for palliative care, learning from system failures, and delivering end of life care in low-resource countries. Sessions were followed by intensive collaborative discussions which helped formulate key recommendations for rethinking and ultimately advancing end of life care. RESULTS: Prominent lessons learned from SGS include learning from low-resource countries, development of evidence-based quality measures, implementing changes in training and education, and respecting the personal agency of patients and their families. CONCLUSION: There is a global need to rethink, and ultimately revolutionize end of life care in all countries. This paper outlines key aspects of end of life care that warrant explicit improvement through specific action from key stakeholders.

Role of PARP-1 as a novel transcriptional regulator of MMP-9 in diabetic retinopathy.

In diabetes, matrix metalloproteinase-9 (MMP-9) is activated, which damages mitochondria, resulting in accelerated capillary cell apoptosis. Regulation of MMP-9 is controlled by multiple transcription factors including nuclear factor-kB (NF-kB) and activator protein-1 (AP-1). Binding of these transcription factors, however, can be regulated by poly(ADP-ribose) polymerase-1 (PARP-1), which forms a strong initiation complex at the promoter region and facilitates multiple rounds of gene transcription. This complex formation with the transcription factors is regulated by posttranslational acetylation of PARP-1, and in diabetes, the deacetylating enzyme, Sirt1, is inhibited. Our aim was to understand the role of PARP-1 in transcriptional regulation of MMP-9 in the development of diabetic retinopathy. Using human retinal endothelial cells, the effect of PARP-1 inhibition (pharmacologically by PJ34, 1µM; or genetically by its siRNA) on MMP-9 expression was investigated. The effect of PARP-1 acetylation on its binding at the MMP-9 promoter, and with NF-kB/AP-1, was investigated in the cells transfected with Sirt1. In vitro results were validated in the retinal microvessels from diabetic mice either administered PJ34, or overexpressing Sirt1. Inhibition of PARP-1 ameliorated hyperglycemia-induced increase in the binding of NF-kB/AP-1 at the MMP-9 promoter, decreased MMP-9 expression and ameliorated mitochondrial damage. Overexpression of Sirt1 attenuated diabetes-induced increase in PARP-1 binding at MMP-9 promoter or with NF-kB/AP-1. Thus, PARP-1, via manipulating the binding of NF-kB/AP-1 at the MMP-9 promoter, regulates MMP-9 expression, which helps maintain mitochondrial homeostasis.