Analysis of the broad-spectrum potential of nitric oxide for antibacterial activity against clinically isolated drug-resistant bacteria.

The development of drug-resistant microorganisms is taking a heavy toll on the biomedical world. Clinical infections are costly and becoming increasingly dangerous as bacteria that once responded to standard antibiotic treatment are developing resistance mechanisms that require innovative treatment strategies. Nitric oxide (NO) is a gaseous molecule produced endogenously that has shown potent antibacterial capabilities in numerous research studies. Its multimechanistic antibacterial methods prevent the development of resistance and have shown potential as an alternative to antibiotics. However, there has yet to be a direct comparison study evaluating the antibacterial properties of NO against antibiotic susceptible and antibiotic-resistant clinically isolated bacterial strains. Herein, standardized lab and clinically isolated drug-resistant bacterial strains are compared side-by-side for growth and viability following treatment with NO released from S-nitrosoglutathione (GSNO), an NO donor molecule. Evaluation of growth kinetics revealed complete killing of E. coli lab and clinical strains at 17.5 mM GSNO, though 15 mM displayed >50% killing and significantly reduced metabolic activity, with greater dose dependence for membrane permeability. Clinical P. aeruginosa showed greater susceptibility to GSNO during growth curve studies, but metabolic activity and membrane permeability demonstrated similar effects for 12.5 mM GSNO treatment of lab and clinical strains. MRSA lab and clinical strains exhibited total killing at 17.5 mM treatment, though metabolic activity was decreased, and membrane permeation began at 12.5 mM for both strains. Lastly, both S. epidermidis strains were killed by 15 mM GSNO, with sensitivities in metabolic activity and membrane permeability at 12.5 mM GSNO. The mirrored antibacterial effects seen by the lab and clinical strains of two Gram-negative and two Gram-positive bacteria reveal the translational success of NO as an antibacterial therapy and potential alternative to standard antibiotic treatment.

Stereoelectroencephalography of the Deep Brain: Basal Ganglia and Thalami.

SUMMARY: Stereoelectroencephalography (SEEG) has emerged as a transformative tool in epilepsy surgery, shedding light on the complex network dynamics involved in focal epilepsy. This review explores the role of SEEG in elucidating the role of deep brain structures, namely the basal ganglia and thalamus, in epilepsy. SEEG advances understanding of their contribution to seizure generation, propagation, and control by permitting precise and minimally invasive sampling of these brain regions. The basal ganglia, comprising the subthalamic nucleus, globus pallidus, substantia nigra, and striatum, have gained recognition for their involvement in both focal and generalized epilepsy. Electrophysiological recordings reveal hyperexcitability and increased synchrony within these structures, reinforcing their role as critical nodes within the epileptic network. Furthermore, low-frequency and high-frequency stimulation of the basal ganglia have demonstrated potential in modulating epileptogenic networks. Concurrently, the thalamus, a key relay center, has garnered prominence in epilepsy research. Disrupted thalamocortical connectivity in focal epilepsy underscores its significance in seizure maintenance. The thalamic subnuclei, including the anterior nucleus, centromedian, and medial pulvinar, present promising neuromodulatory targets, suggesting pathways for personalized epilepsy therapies. The prospect of multithalamic SEEG and thalamic SEEG stimulation trials has the potential to revolutionize epilepsy management, offering tailored solutions for challenging cases. SEEG's ability to unveil the dynamics of deep brain structures in epilepsy promises enhanced and personalized epilepsy care in our new era of precision medicine. Until deep brain SEEG is accepted as a standard of care, a rigorous informed consent process remains paramount for patients for whom such an exploration is proposed.

Binding of carbon dioxide and acetylene to free carboxylic acid sites in a metal-organic framework.

The functionalisation of organic linkers in metal-organic frameworks (MOFs) to improve gas uptake is well-documented. Although the positive role of free carboxylic acid sites in MOFs for binding gas molecules has been proposed in computational studies, relatively little experimental evidence has been reported in support of this. Primarily this is because of the inherent synthetic difficulty to prepare MOF materials bearing free, accessible -COOH moieties which would normally bind to metal ions within the framework structure. Here, we describe the direct binding of CO2 and C2H2 molecules to the free -COOH sites within the pores of MFM-303(Al). MFM-303(Al) exhibits highly selective adsorption of CO2 and C2H2 with a high selectivity for C2H2 over C2H4. In situ synchrotron X-ray diffraction and inelastic neutron scattering, coupled with modelling, highlight the cooperative interactions of adsorbed CO2 and C2H2 molecules with free -COOH and -OH sites within MFM-303(Al), thus rationalising the observed high selectivity for gas separation.

Molecular transformations and self-association in anthocyanin pigment patterns.

Spatial patterns of red, purple, and blue colors due to plant pigments called anthocyanins appear in a wide variety of flower petals. Activator and inhibitor proteins involved in anthocyanin synthesis in Mimulus (monkeyflowers) have been identified, and an activator-inhibitor system based on the classic Gierer-Meinhardt system has been proposed as a mathematical model. Analysis in this paper provides a prediction for the critical value of a dimensionless parameter, the ratio of the degradation rate constants of the inhibitor and activator, for pattern formation to occur, and numerical simulations demonstrate the potential for this system to form disordered hexagonal or stripe patterns. We provide experimental evidence for spatial variation in total anthocyanin concentration and for concentration-dependent anthocyanin association. Extending the mathematical model to include anthocyanin transport and diffusion, a series of molecular transformations encompassing acid-base and hydration (speciation) reactions, and self association, we predict that spatial color patterns are accompanied by complex spatial variation in the degree of self association. An important consequence of these studies is a proposal that anthocyanin association allows for colored anthocyanin species to be present in large mole fractions in cell vacuoles despite the fact that the typical vacuolar pH range favors the formation of colorless species.

The value of additional electrodes when stereo-electroencephalography is inconclusive.

OBJECTIVE: Stereo-electroencephalography (SEEG) is the preferred method for intracranial localization of the seizure-onset zone (SOZ) in drug-resistant focal epilepsy. Occasionally SEEG evaluation fails to confirm the pre-implantation hypothesis. This leads to a decision tree regarding whether the addition of SEEG electrodes (two-step SEEG - 2sSEEG) or placement of subdural electrodes (SDEs) after SEEG (SEEG2SDE) would help. There is a dearth of literature encompassing this scenario, and here we aimed to characterize outcomes following unplanned two-step intracranial EEG (iEEG). METHODS: All 225 adult SEEG cases over 8 years at our institution were reviewed to extract patient data and outcomes following a two-step evaluation. Three raters independently quantified benefits of additional intracranial electrodes. The relationship between two-step iEEG benefit and clinical outcome was then analyzed. RESULTS: Fourteen patients underwent 2sSEEG and nine underwent SEEG2SDE. In the former cohort, the second SEEG procedure was performed for these reasons-precise localization of the SOZ (36%); defining margins of eloquent cortex (21%); and broadening coverage in the setting of non-localizable seizure onsets (43% of cases). Sixty-four percent of 2sSEEG cases were consistently deemed beneficial (Light's κ = 0.80). 2sSEEG performed for the first two indications was much more beneficial than when onsets were not localizable (100% vs 17%, p = .02). In the SEEG2SDE cohort, SDEs identified the SOZ and enabled delineation of margins relative to eloquent cortex in all cases. SIGNIFICANCE: The two-step iEEG is useful if the initial evaluation is broadly concordant with the original electroclinical hypothesis, where it can clarify onset zones or delineate safe surgical margins; however, it provides minimal benefit when the implantation hypothesis is erroneous, and we recommend that 2sSEEG not be generally utilized in such cases. SDE implantation after SEEG minimizes the need for SDEs and is helpful in delineating surgical boundaries relative to ictal-onset zones and eloquent cortex.

Design of the Global Health chemical diversity library v2 for screening against infectious diseases.

There is a need for novel chemical matter for phenotypic and target-based screens to find starting points for drug discovery programmes in neglected infectious diseases and non-hormonal contraceptives that disproportionately affect Low- and Middle-Income Countries (LMICs). In some disease areas multiple screens of corporate and other libraries have been carried out, giving rise to some valuable starting points and leading to preclinical candidates. Whilst in other disease areas, little screening has been carried out. Much screening against pathogens has been conducted phenotypically as there are few robustly validated protein targets. However, many of the active compound series identified share the same molecular targets. To address the need for new chemical material, in this article we describe the design of a new library, designed for screening in drug discovery programmes for neglected infectious diseases. The compounds have been selected from the Enamine REAL (REadily AccessibLe) library, a virtual library which contains approximately 4.5 billion molecules. The molecules theoretically can be synthesized quickly using commercially available intermediates and building blocks. The vast majority of these have not been prepared before, so this is a source of novel compounds. In this paper we describe the design of a diverse library of 30,000 compounds from this collection (graphical abstract). The new library will be made available to laboratories working in neglected infectious diseases, subject to a review process. The project has been supported by the Bill & Melinda Gates Foundation and the Wellcome Trust (Wellcome).

The role of radiation therapy in the management of primary retroperitoneal sarcoma: A systematic review and clinical practice guidelines from the Australia and New Zealand Sarcoma Association.

While surgery is the mainstay of treatment for localised retroperitoneal sarcoma, the use of radiotherapy (RT) remains controversial. This systematic review aimed to evaluate the role of RT for retroperitoneal sarcoma. A systematic review using the population, intervention, comparison, and outcome model from 1990 to 2022 identified 66 studies (a mixture of preoperative and postoperative RT); one randomised controlled trial (RCT) with two publications, 18 registry studies, and 46 retrospective studies. In the RCT of preoperative RT, there was no difference in local/abdominal recurrence. The pooled analysis of this RCT and a retrospective study showed a significant abdominal recurrence free survival benefit with preoperative RT in low grade liposarcoma. The RCT and the majority of retrospective series found RT did not improve recurrence free survival (11 of 16 no difference in combined local and distant RFS, 11 of 13 no difference in distant metastasis free survival), disease specific survival (9 of 12 studies) or overall survival (33 of 49 studies). The majority of studies found no association between RT and perioperative morbidity. In summary, preoperative RT may improve local control for low grade (well-differentiated or grades 1-2 dedifferentiated) liposarcoma, but not other histological subtypes. There is no strong evidence that perioperative RT provides an overall survival benefit. Patients with low grade retroperitoneal liposarcoma can be considered for preoperative RT to improve abdominal recurrence free survival. The rationale and level of evidence in this scenario should be carefully discussed by the multidisciplinary team with patients. RT should not be routinely recommended for other histological subtypes.

Case report: Acute necrotizing encephalopathy: a report of a favorable outcome and systematic meta-analysis of outcomes with different immunosuppressive therapies.

Acute Necrotizing Encephalopathy (ANE) is a condition characterized by symmetric, bilateral lesions affecting the thalamus and potentially other areas of the brain following an acute febrile illness. It manifests clinically as abrupt development of encephalopathy, or alteration in mental status that often includes development of seizures and progression to coma. Treatment strategies combine immunosuppressive therapies and supportive care with varying levels of recovery, however there are no universally accepted, data-driven, treatment algorithms for ANE. We first report a case of a previously healthy 10-year-old female with acute onset diplopia, visual hallucinations, lethargy, and seizures in the setting of subacute non-specific viral symptoms and found to have bilateral thalamic and brainstem lesions on MRI consistent with ANE. She was treated with a combination of immunomodulatory therapies and ultimately had a good outcome. Next, we present a meta-analysis of 10 articles with a total of 158 patients meeting clinical and radiographic criteria for ANE. Each article reported immunosuppressive treatments received, and associated morbidity or mortality outcome for each individual patient. Through our analysis, we confirm the effectiveness of high-dose, intravenous, methylprednisolone (HD-IV-MP) therapy implemented early in the disease course (initiation within 24 h of neurologic symptom onset). There was no significant difference between patients treated with and without intravenous immunoglobulin (IVIG). There was no benefit of combining IVIG with early HD-IV-MP. There is weak evidence suggesting a benefit of IL-6 inhibitor tocilizumab, especially when used in combination with early HD-IV-MP, though this analysis was limited by sample size. Finally, plasma exchange (PLEX) improved survival. We hope this meta-analysis will be useful for clinicians making treatment decisions for patients with this potentially devastating condition.

Enhanced Surgeons: Understanding the Design of Augmented Reality Instructions for Keyhole Surgery.

It is important to understand how to design AR content for surgical contexts to mitigate the risk of distracting the surgeons. In this work, we test information overlays for AR guidance during keyhole surgery. We performed a preliminary evaluation of a prototype, focusing on the effects of colour, opacity, and information representation. Our work contributes insights into the design of AR guidance in surgery settings and a foundation for future research on visualisation design for surgical AR.

Comparison of three analgesic regimens in women undergoing cervical brachytherapy.

PURPOSE: Effective periprocedural analgesia is an important aspect of cervical brachytherapy delivery, with implications for patient comfort and attendance for subsequent fractions. We compared the efficacy and safety of three analgesic modalities: intravenous patient-controlled analgesia (IV-PCA), continuous epidural infusion (CEI) and programmed-intermittent epidural bolus with patient-controlled epidural analgesia (PIEB-PCEA). METHODS AND MATERIALS: Ninety-seven brachytherapy episodes involving 36 patients between July 2016 and June 2019 in a single tertiary center were retrospectively reviewed. Episodes were divided into two key phases: Phase 1 (while applicator remained in situ) and Phase 2 (following applicator removal until discharge or 4 h). For the primary endpoint, pain scores were retrieved and analyzed by analgesic modality with respect to median score and an internally defined "unacceptable" pain experience (>20% of scores being ≥4/10; i.e., moderate or greater). Total nonepidural oral morphine equivalent dose (OMED) and toxicity/complication events were reported as secondary endpoints. RESULTS: In Phase 1, there was a significantly higher median pain score (p < 0.001) and more episodes with unacceptable pain scores (46%) in the IV-PCA group compared with either epidural modality (6-14%; p < 0.001). In Phase 2, we observed a greater median pain score (p = 0.007) and higher proportion of patient episodes with unacceptable pain scores (38%) in the CEI group compared with both the IV-PCA (13%) and PIEB-PCEA (14%) groups (p = 0.001). There was a significant difference in median OMED used throughout all phases across the PIEB-PCEA (0 mg), IV-PCA (70 mg), and CEI (15 mg) groups (p < 0.001). CONCLUSIONS: PIEB-PCEA is safe and offers superior analgesia compared to IV-PCA or CEI for pain control after applicator placement in cervical brachytherapy.

Development of a 2,4-Diaminothiazole Series for the Treatment of Human African Trypanosomiasis Highlights the Importance of Static-Cidal Screening of Analogues.

While treatment options for human African trypanosomiasis (HAT) have improved significantly, there is still a need for new drugs with eradication now a realistic possibility. Here, we report the development of 2,4-diaminothiazoles that demonstrate significant potency against Trypanosoma brucei, the causative agent of HAT. Using phenotypic screening to guide structure-activity relationships, potent drug-like inhibitors were developed. Proof of concept was established in an animal model of the hemolymphatic stage of HAT. To treat the meningoencephalitic stage of infection, compounds were optimized for pharmacokinetic properties, including blood-brain barrier penetration. However, in vivo efficacy was not achieved, in part due to compounds evolving from a cytocidal to a cytostatic mechanism of action. Subsequent studies identified a nonessential kinase involved in the inositol biosynthesis pathway as the molecular target of these cytostatic compounds. These studies highlight the need for cytocidal drugs for the treatment of HAT and the importance of static-cidal screening of analogues.

Surgery at specialised sarcoma centres improves patient outcomes - A systematic review by the Australia and New Zealand sarcoma association clinical practice guidelines working party.

BACKGROUND: Optimal management of sarcoma requires multidisciplinary team input throughout the process of diagnosis, treatment and follow up. This systematic review aimed to evaluate the impact of surgery performed at specialised sarcoma centres on outcomes. METHODS: A systematic review was conducted using the population, intervention, comparison and outcome (PICO) model. Medline, Embase, Cochrane Central databases were queried for publications that evaluated the local control, limb salvage rate, 30-day and 90-day surgical mortality, and overall survival in patients undergoing surgery in a specialist sarcoma centre compared with non-specialist centre. Each study was screened by two independent reviewers for suitability. A qualitative synthesis of the results was performed. RESULTS: Sixty-six studies were identified. The majority of studies were Level III-3 as assessed by the NHMRC Evidence Hierarchy, whilst just over half of the studies were of good quality. Definitive surgery performed at specialised sarcoma centres was associated with improved local control as defined by lower rate of local relapse, higher rate of negative surgical margins, improved local recurrence free survival and higher limb conservation rate. Available evidences show a favourable pattern of lower 30-day and 90-day mortality rates, and greater overall survival when surgery was performed in specialist sarcoma centres compared with non-specialised centres. CONCLUSIONS: Evidences support better oncological outcomes when surgery is performed at specialised sarcoma centre. Patients with suspected sarcoma should be referred early to a specialised sarcoma centre for multidisciplinary management, which includes planned biopsy and definitive surgery.

Clinical characteristics and patient-reported outcomes of chronic and episodic migraine patients at a US tertiary headache center: A retrospective observational study.

OBJECTIVE: To describe differences in clinical and demographic characteristics between patients with episodic migraine (EM) or chronic migraine (CM) and determine the effect of migraine subtype on patient-reported outcome measures (PROM). BACKGROUND: Prior studies have characterized migraine in the general population. While this provides a basis for our understanding of migraine, we have less insight into the characteristics, comorbidities, and outcomes of migraine patients who present to subspecialty headache clinics. These patients represent a subset of the population that bears the greatest burden of migraine disability and are more representative of migraine patients who seek medical care. Valuable insights can be gained from a better understanding of CM and EM in this population. METHODS: We conducted a retrospective observational cohort study of patients with CM or EM seen in the Cleveland Clinic Headache Center between January 2012 and June 2017. Demographics, clinical characteristics, and patient-reported outcome measures (3-Level European Quality of Life 5-Dimension [EQ-5D-3L], Headache Impact Test-6 [HIT-6], Patient Health Questionnaire-9 [PHQ-9]) were compared between groups. RESULTS: Eleven thousand thirty-seven patients who had 29,032 visits were included. More CM patients reported being on disability 517/3652 (14.2%) than EM patients 249/4881 (5.1%) and had significantly worse mean HIT-6 (67.3 ± 7.4 vs. 63.1 ± 7.4, p < 0.001) and median [interquartile range] EQ-5D-3L (0.77 [0.44-0.82] vs. 0.83 [0.77-1.00], p < 0.001), and PHQ-9 (10 [6-16] vs. 5 [2-10], p < 0.001). CONCLUSIONS: There are multiple differences in demographic characteristics and comorbid conditions between patients with CM and EM. After adjustment for these factors, CM patients had higher PHQ-9 scores, lower quality of life scores, greater disability, and greater work restrictions/unemployment.

Kindling in humans: Does secondary epileptogenesis occur?

The relevance of secondary epileptogenesis for human epilepsy remains a controversial subject decades after it was first described in animal models. Whether or not a previously normal brain region can become independently epileptogenic through a kindling-like process has not, and cannot, be definitely proven in humans. Rather than reliance on direct experimental evidence, attempts to answering this question must depend on observational data. In this review, observations based largely upon contemporary surgical series will advance the case for secondary epileptogenesis in humans. As will be argued, hypothalamic hamartoma-related epilepsy provides the strongest case for this process; all the stages of secondary epileptogenesis can be observed. Hippocampal sclerosis (HS) is another pathology where the question of secondary epileptogenesis frequently arises, and observations from bitemporal and dual pathology series are explored. The verdict here is far more difficult to reach, in large part because of the scarcity of longitudinal cohorts; moreover, recent experimental data have challenged the claim that HS is acquired consequent to recurrent seizures. Synaptic plasticity more than seizure-induced neuronal injury is the likely mechanism of secondary epileptogenesis. Postoperative running-down phenomenon provides the best evidence that a kindling-like process occurs in some patients, evidenced by its reversal. Finally, a network perspective of secondary epileptogenesis is considered, as well as the possible role for subcortical surgical interventions.

Can the Oral Bioavailability of the Discontinued Prostate Cancer Drug Galeterone Be Improved by Processing Method? KinetiSol® Outperforms Spray Drying in a Head-to-head Comparison.

Galeterone, a novel prostate cancer candidate treatment, was discontinued after a Phase III clinical trial due to lack of efficacy. Galeterone is weakly basic and exhibits low solubility in biorelevant media (i.e., ~ 2 µg/mL in fasted simulated intestinal fluid). It was formulated as a 50-50 (w/w) galeterone-hypromellose acetate succinate spray-dried dispersion to increase its bioavailability. Despite this increase, the bioavailability of this formulation may have been insufficient and contributed to its clinical failure. We hypothesized that reformulating galeterone as an amorphous solid dispersion by KinetiSol® compounding could increase its bioavailability. In this study, we examined the effects of composition and manufacturing technology (Kinetisol and spray drying) on the performance of galeterone amorphous solid dispersions. KinetiSol compounding was utilized to create galeterone amorphous solid dispersions containing the complexing agent hydroxypropyl-ß-cyclodextrin or hypromellose acetate succinate with lower drug loads that both achieved a ~ 6 × increase in dissolution performance versus the 50-50 spray-dried dispersion. When compared to a spray-dried dispersion with an equivalent drug load, the KinetiSol amorphous solid dispersions formulations exhibited ~ 2 × exposure in an in vivo rat study. Acid-base surface energy analysis showed that the equivalent composition of the KinetiSol amorphous solid dispersion formulation better protected the weakly basic galeterone from premature dissolution in acidic media and thereby reduced precipitation, inhibited recrystallization, and extended the extent of supersaturation during transit into neutral intestinal media.

Characterization of a Helicobacter pylori strain with high biofilm-forming ability.

Introduction. Helicobacter pylori is highly polymorphic, and some strains are much more likely to cause disease than others. Biofilm formation can help bacteria to survive antibiotic treatment, immune attack and other stresses, promoting persistent infection.Hypothesis/Gap Statement. We hypothesized that H. pylori isolates from patients with more severe H. pylori-associated disease would be better at forming biofilms than isolates from patients with less severe disease.Aim. We initially aimed to determine whether or not the biofilm-forming ability of H. pylori isolates was associated with disease in the UK-based patients from whom the bacteria were isolated.Methodology. Biofilm-forming ability of H. pylori isolates was determined using a crystal violet assay on glass coverslips. The complete genome sequence of strain 444A was generated by hybrid assembly of Nanopore MinION and Illumina MiSeq data.Results. Although we found no associations between biofilm-forming ability of H. pylori and disease severity in patients, we discovered that strain 444A had particularly high biofilm-forming ability. This strain had been isolated from a patient with gastric ulcer disease and moderate to severe scores for H. pylori-induced histopathology. Analysis of the genome of the high biofilm-forming H. pylori strain 444A revealed that it possesses numerous biofilm- and virulence-associated genes and a small cryptic plasmid encoding a type II toxin-antitoxin system.Conclusion. There is substantial variation in biofilm-forming ability in H. pylori, but this was not significantly associated with disease severity in our study. We identified and characterized an interesting strain with high biofilm-forming ability, including generation and analysis of the complete genome.

Pre-Processing a Polymer Blend into a Polymer Alloy by KinetiSol Enables Increased Ivacaftor Amorphous Solid Dispersion Drug Loading and Dissolution.

This study compares the effects of pre-processing multiple polymers together to form a single-phase polymer alloy prior to amorphous solid dispersion formulation. KinetiSol compounding was used to pre-process a 1:1 (w/w) ratio of hypromellose acetate succinate and povidone to form a single-phase polymer alloy with unique properties. Ivacaftor amorphous solid dispersions comprising either a polymer, an unprocessed polymer blend, or the polymer alloy were processed by KinetiSol and examined for amorphicity, dissolution performance, physical stability, and molecular interactions. A polymer alloy ivacaftor solid dispersion with a drug loading of 50% w/w was feasible versus 40% for the other compositions. Dissolution in fasted simulated intestinal fluid revealed that the 40% ivacaftor polymer alloy solid dispersion reached a concentration of 595 µg/mL after 6 h, 33% greater than the equivalent polymer blend dispersion. Fourier transform infrared spectroscopy and solid-state nuclear magnetic resonance revealed changes in the ability of the povidone contained in the polymer alloy to hydrogen bond with the ivacaftor phenolic moiety, explaining the differences in the dissolution performance. This work demonstrates that the creation of polymer alloys from polymer blends is a promising technique that provides the ability to tailor properties of a polymer alloy to maximize the drug loading, dissolution performance, and stability of an ASD.