Bacterial Photodynamic Inactivation: Eradication of and Mediated by Pyridinium-Pyrazolyl Zinc(II) Phthalocyanines.

Antimicrobial resistance remains an enduring global health issue, manifested when microorganisms, such as bacteria, lack responsiveness to antimicrobial treatments. Photodynamic inactivation (PDI) of microorganisms arises as a noninvasive, nontoxic, and repeatable alternative for the inactivation of a broad range of pathogens. So, this study reports the synthesis, structural characterization, and photophysical properties of a new tetra-β-substituted pyridinium-pyrazolyl zinc(II) phthalocyanine (ZnPc ) that was compared with two previously described pyridinium-pyrazolyl ZnPcs and .

Insight into the efficiency of microalgae' lipidic extracts as photosensitizers for Antimicrobial Photodynamic Therapy against Staphylococcus aureus.

Antibacterial resistance causes around 1.27 million deaths annually around the globe and has been recognized as a top 3 priority health threat. Antimicrobial photodynamic therapy (aPDT) is considered a promising alternative to conventional antibiotic treatments.

Can Porphyrin-Triphenylphosphonium Conjugates Enhance the Photosensitizer Performance Toward Bacterial Strains?

Antimicrobial photodynamic treatment (aPDT) offers an alternative option for combating microbial pathogens, and in this way, addressing the challenges of growing antimicrobial resistance. In this promising and effective approach, cationic porphyrins and related macrocycles have emerged as leading photosensitizers (PS) for aPDT. In general, their preparation occurs via -alkylation of nitrogen-based moieties with alkyl halides, which limits the ability to fine-tune the features of porphyrin-based PS.

Wastewater disinfection with photodynamic treatment and evaluation of its ecotoxicological effects.

Research has demonstrated the presence of viruses in wastewater (WW), which can remain viable for a long period, posing potential health risks. Conventional WW treatment methods involving UV light, chlorine and ozone efficiently reduce microbial concentrations, however, they produce hazardous byproducts and microbial resistance that are detrimental to human health and the ecosystem. Hence, there is a need for novel disinfection techniques.

Adenosinergic System and BDNF Signaling Changes as a Cross-Sectional Feature of RTT: Characterization of Heterozygous Mouse Females.

Rett Syndrome is an X-linked neurodevelopmental disorder (RTT; OMIM#312750) associated to mutations. MeCP2 dysfunction is seen as one cause for the deficiencies found in brain-derived neurotrophic factor (BDNF) signaling, since BDNF is one of the genes under MeCP2 jurisdiction. BDNF signaling is also dependent on the proper function of the adenosinergic system.

Sulfonamide Porphyrins as Potent Photosensitizers against Multidrug-Resistant (MRSA): The Role of Co-Adjuvants.

Sulfonamides are a conventional class of antibiotics that are well-suited to combat infections. However, their overuse leads to antimicrobial resistance. Porphyrins and analogs have demonstrated excellent photosensitizing properties and have been used as antimicrobial agents to photoinactivate microorganisms, including multiresistant (MRSA) strains.

Bioprospecting antibiotic properties in photodynamic therapy of lipids from Codium tomemtosum and Chlorella vulgaris.

The growing resistance from pathogens against antibiotics has increased the research for new compounds and strategies with antibacterial potential. Lipids from algae are emerging as natural and potent bioactive molecules with interesting results regarding the inactivation of bacteria, viruses, and fungi. The combination of algae lipids with innovative strategies, such as antibacterial photodynamic therapy (aPDT) can enhance their antimicrobial potential.

Photodynamic inactivation of pathogenic Gram-negative and Gram-positive bacteria mediated by Si(IV) phthalocyanines bearing axial ammonium units.

The photodynamic inactivation (PDI) of microorganisms has gained interest as an efficient option for conventional antibiotic treatments. Recently, Si(IV) phthalocyanines (SiPcs) have been highlighted as promising photosensitizers (PSs) to the PDI of microorganisms due to their remarkable absorption and emission features. To increase the potential of cationic SiPcs as PS drugs, one novel (1a) and two previously described (2a and 3a) axially substituted PSs with di-, tetra-, and hexa-ammonium units, respectively, were synthesized and characterized.

Photoinactivation of Phage Phi6 as a SARS-CoV-2 Model in Wastewater: Evidence of Efficacy and Safety.

The last two years have been marked by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. This virus is found in the intestinal tract; it reaches wastewater systems and, consequently, the natural receiving water bodies. As such, inefficiently treated wastewater (WW) can be a means of contamination.

β Adrenoceptor-induced cholinergic inhibition in human and rat urinary bladders involves the exchange protein directly activated by cyclic AMP 1 favoring adenosine release.

Background And Purpose: The mechanism by which β receptor agonists (e.g. mirabegron) control bladder overactivity may involve adenosine release from human and rat detrusor smooth muscle.

An Insight Into the Potentiation Effect of Potassium Iodide on aPDT Efficacy.

Antimicrobial photodynamic therapy (aPDT) is gaining a special importance as an effective approach against multidrug-resistant strains responsible of fatal infections. The addition of potassium iodide (KI), a non-toxic salt, is recognized to increase the aPDT efficiency of some photosensitizers (PSs) on a broad-spectrum of microorganisms. As the reported cases only refer positive aPDT potentiation results, in this work we selected a broad range of porphyrinic and non-porphyrinic PSs in order to gain a more comprehensive knowledge about this aPDT potentiation by KI.

Post-inflammatory Ileitis Induces Non-neuronal Purinergic Signaling Adjustments of Cholinergic Neurotransmission in the Myenteric Plexus.

Uncoupling between ATP overflow and extracellular adenosine formation changes purinergic signaling in post-inflammatory ileitis. Adenosine neuromodulation deficits were ascribed to feed-forward inhibition of ecto-5'-nucleotidase/CD73 by high extracellular adenine nucleotides in the inflamed ileum. Here, we hypothesized that inflammation-induced changes in cellular density may also account to unbalance the release of purines and their influence on [H]acetylcholine release from longitudinal muscle-myenteric plexus preparations of the ileum of 2,4,6-trinitrobenzenesulfonic acid (TNBS)-treated rats.

The Effect of Ischemia and Reperfusion on Enteric Glial Cells and Contractile Activity in the Ileum.

Background: We investigated the effects of ischemia followed by different periods of reperfusion (I/R) on immunoreactive S100β-positive glial and Hu-immunoreactive neurons co-expressing the P2X2 receptor in the myenteric plexus of the rat ileum.

Methods: The ileal artery was occluded for 35 min with an atraumatic vascular clamp. The animals were killed 24 h, 72 h, and 1 week after ischemia.

Improving the MDR reversal activity of 6,17-epoxylathyrane diterpenes.

Aiming to optimize macrocyclic lathyrane-type diterpenes as effective Pgp modulators, the phytochemical study of the methanolic extract of Euphorbia boetica aerial parts was carried out. Two new macrocyclic 6,17-epoxylathyrane-type diterpenes, named epoxyboetiranes A (1) and B (2), along with three known analogues (3-5) were isolated. Epoxyboetirane A (1), a triacetate isolated in large amounts, was hydrolyzed to give epoxylathyrol (6).

Feed-forward inhibition of CD73 and upregulation of adenosine deaminase contribute to the loss of adenosine neuromodulation in postinflammatory ileitis.

Purinergic signalling is remarkably plastic during gastrointestinal inflammation. Thus, selective drugs targeting the "purinome" may be helpful for inflammatory gastrointestinal diseases. The myenteric neuromuscular transmission of healthy individuals is fine-tuned and controlled by adenosine acting on A(2A) excitatory receptors.

Activation of P2Y6 receptors increases the voiding frequency in anaesthetized rats by releasing ATP from the bladder urothelium.

Background And Purpose: Despite the abundant expression of the UDP-sensitive P2Y6 receptor in urothelial cells and sub-urothelial myofibroblasts its role in the control of bladder function is not well understood.

Experimental Approach: We compared the effects of UDP and of the selective P2Y6 receptor agonist, PSB0474, on bladder urodynamics in anaesthetized rats; the voided fluid was tested for ATP bioluminescence. The isolated urinary bladder was used for in vitro myographic recordings and [(3) H]-ACh overflow experiments.

Mechanisms of P-gp inhibition and effects on membrane fluidity of a new rifampicin derivative, 1,8-dibenzoyl-rifampicin.

Purpose: To assess P-glycoprotein (P-gp)-modulation ability and the mechanisms of P-gp inhibition mediated by a new synthetic rifampicin derivative, 1,8-dibenzoyl-rifampicin (DiBenzRif), in an in vitro model of the blood-brain barrier (BBB), RBE4 cells, and in membrane mimetic models (liposomes).

Methods: P-gp expression (western blot) and activity [rhodamine 123 accumulation studies] were assessed until 72h of exposure to DiBenzRif. The effects on intracellular ATP levels and on P-gp ATPase activity were studied using luciferin-luciferase bioluminescence assay.

Localization and function of adenosine receptor subtypes at the longitudinal muscle--myenteric plexus of the rat ileum.

Adenosine plays a dual role on acetylcholine (ACh) release from myenteric motoneurons via the activation of high-affinity inhibitory A₁ and facilitatory A(2A) receptors. The therapeutic potential of adenosine-related compounds for controlling intestinal motility and inflammation, prompted us to investigate further the role of low-affinity adenosine receptors, A(2B) and A₃, on electrically-evoked (5 Hz, 200 pulses) [³H]ACh release from myenteric neurons. Immunolocalization studies showed that A(2B) receptors exhibit a pattern of distribution similar to the glial cell marker, GFAP.

Fine-tuning modulation of myenteric motoneurons by endogenous adenosine: on the role of secreted adenosine deaminase.

Besides the well-characterized inhibitory effect of adenosine in the gastrointestinal tract mediated by A1 receptors, we recently demonstrated that endogenously generated adenosine facilitates [3H]acetylcholine release from myenteric neurons through preferential activation of prejunctional A2A receptors. The co-existence of both receptor subtypes on cholinergic neurons prompted the question of how does adenosine discriminate between these receptors to regulate synaptic transmission in the longitudinal muscle-myenteric plexus (LM-MP) of the rat ileum. Electrical stimulation of the LM-MP increased the outflow of adenosine, inosine and hypoxanthine.