SigH stress response mediates killing of Mycobacterium tuberculosis by activating nitronaphthofuran prodrugs via induction of Mrx2 expression.

The emergence of drug-resistant Mycobacterium tuberculosis strains highlights the need to discover anti-tuberculosis drugs with novel mechanisms of action. Here we discovered a mycobactericidal strategy based on the prodrug activation of selected chemical derivatives classified as nitronaphthofurans (nNFs) mediated by the coordinated action of the sigH and mrx2 genes. The transcription factor SigH is a key regulator of an extensive transcriptional network that responds to oxidative, nitrosative, and heat stresses in M. tuberculosis. The nNF action induced the SigH stress response which in turn induced the mrx2 overexpression. The nitroreductase Mrx2 was found to activate nNF prodrugs, killing replicating, non-replicating and intracellular forms of M. tuberculosis. Analysis of SigH DNA sequences obtained from spontaneous nNF-resistant M. tuberculosis mutants suggests disruption of SigH binding to the mrx2 promoter site and/or RNA polymerase core, likely promoting the observed loss of transcriptional control over Mrx2. Mutations found in mrx2 lead to structural defects in the thioredoxin fold of the Mrx2 protein, significantly impairing the activity of the Mrx2 enzyme against nNFs. Altogether, our work brings out the SigH/Mrx2 stress response pathway as a promising target for future drug discovery programs.

Defining a Target Population to Effectively Test a Neuroprotective Drug.

BACKGROUND AND PURPOSE: We aim to identify the subgroup of acute ischemic stroke patients with higher probabilities of benefiting from a potential neuroprotective drug using baseline outcome predictors and test whether different selection criteria strategies can improve detected treatment effect. METHODS: We analyzed the association between final infarct volume (FIV), measured on 24- to 72-hour computed tomography, and National Institutes of Health Stroke Scale at discharge/day 5 of acute stroke patients who underwent endovascular treatment. Models were adjusted for age, sex, and affected hemisphere. We analyzed the impact of absolute (5-15 mL) and relative (33%) FIV reductions in the National Institutes of Health Stroke Scale in the whole population and in different subsets of patients selected according to baseline imaging criteria using computed tomography perfusion. RESULTS: We analyzed 627 patients; association between FIV and 5-day National Institutes of Health Stroke Scale was best described with a quadratic function, with a regression coefficient ß=1.56 ([95% CI, 1.45-1.67] P<0.001) in the adjusted analysis. In the models considering a fixed absolute (5/15 mL) FIV reduction, treatment effect was highest when patients with predicted larger FIV were excluded, whereas in a 33% FIV reduction model, treatment effect increased with the exclusion of patients with expected excellent outcomes. CONCLUSIONS: Patients either with excellent outcomes after endovascular thrombectomy or with large infarcts may dilute the treatment effect in stroke neuroprotective drug trials. Computed tomography perfusion on admission may help selecting adequate patients according to expected drug effect profile.

Nutraceutical Extract from Dulse (Palmaria palmata L.) Inhibits Primary Human Neutrophil Activation.

Palmaria palmata L. (Palmariaceae), commonly known as "dulse", is a red alga that grows on the northern coasts of the Atlantic and Pacific oceans, and is widely used as source of fiber and protein. Dulse is reported to contain anti-inflammatory and antioxidant compounds, albeit no study has investigated these effects in primary human neutrophils. Implication strategies to diminish neutrophil activation have the potential to prevent pathological states. We evaluated the ability of a phenolic dulse extract (DULEXT) to modulate the lipopolysaccharide (LPS)-mediated activation of primary human neutrophils. Intracellular reactive oxygen species (ROS) were measured by fluorescence analysis and nitric oxide (NO) production using the Griess reaction. Inflammatory enzymes and cytokines were detected by ELISA and RT-qPCR. The results show that DULEXT diminished the neutrophil activation related to the down-regulation of TLR4 mRNA expression, deceased gene expression and the LPS-induced release of the chemoattractant mediator IL-8 and the pro-inflammatory cytokines IL-1ß, IL-6 and TNF-α. ROS, NO, and myeloperoxidase (MPO) were also depressed. The data indicated that DULEXT has the potential to disrupt the activation of human primary neutrophils and the derived inflammatory and prooxidant conditions, and suggest a new role for Palmaria palmata L. in the regulation of the pathogenesis of health disorders in which neutrophils play a key role, including atherosclerosis.

Optimization of lipase production by solid-state fermentation of olive pomace: from flask to laboratory-scale packed-bed bioreactor.

Lipases are versatile catalysts with many applications and can be produced by solid-state fermentation (SSF) using agro-industrial wastes. The aim of this work was to maximize the production of Aspergillus ibericus lipase under SSF of olive pomace (OP) and wheat bran (WB), evaluating the effect on lipase production of C/N ratio, lipids, phenols, content of sugars of substrates and nitrogen source addition. Moreover, the implementation of the SSF process in a packed-bed bioreactor and the improvement of lipase extraction conditions were assessed. Low C/N ratios and high content of lipids led to maximum lipase production. Optimum SSF conditions were achieved with a C/N mass ratio of 25.2 and 10.2% (w/w) lipids in substrate, by the mixture of OP:WB (1:1) and supplemented with 1.33% (w/w) (NH4)2SO4. Studies in a packed-bed bioreactor showed that the lower aeration rates tested prevented substrate dehydration, improving lipase production. In this work, the important role of Triton X-100 on lipase extraction from the fermented solid substrate has been shown. A final lipase activity of 223 ± 5 U g-1 (dry basis) was obtained after 7 days of fermentation.

Ferulic acid transformation into the main vanilla aroma compounds by Amycolatopsis sp. ATCC 39116.

The wild strain Amycolatopsis sp. ATCC 39116 was explored in ferulic acid-based media to produce naturally the aroma components of the cured vanilla pod, namely vanillin,vanillic acid, and vanillyl alcohol. Other phenolic compounds(4-vinyl guaiacol, guaiacol, and protocatechuic acid) were also evaluated. The influence of medium composition,fermentation technology (batch or fed-batch), supplementation with vanillic acid, and inoculum concentration on ferulic acid biotransformation were evaluated. The results postulate the initial concentration of cell mass as the variable with the strongest impact on ferulic acid metabolization under the studied conditions. The highest amounts of vanillin and vanillic acid were achieved at intermediate values of cell mass.Vanillyl alcohol and protocatechuic acid were more closely linked to high cell mass concentrations. Conversely, 4-vinyl guaiacol reached its highest amount at the lowest amount of cell mass. Guaiacol was not detected in any case. Therefore,the initial cell concentration must be considered a critical parameter when using Amycolaptosis sp. ATCC 39116 for the production of vanillin and related compounds.

Use of Vine-Trimming Wastes as Carrier for Amycolatopsis sp. to Produce Vanillin, Vanillyl Alcohol, and Vanillic Acid.

Raw vine-trimming wastes or the solid residues obtained after different fractionation treatments were evaluated for their suitability as Amycolatopsis sp. immobilization carriers during the bioconversion of ferulic acid into valuable phenolic compounds such as vanillin, vanillyl alcohol, and vanillic acid, the main flavor components of vanilla pods. Previously, physical-chemical characteristics of the materials were determined by quantitative acid hydrolysis and water absorption index (WAI), and microbiological characteristics by calculating the cell retention in the carrier (λ). Additionally, micrographics of carrier surface were obtained by field emission-scanning electron microscopy to study the influence of morphological changes during pretreatments in the adhesion of cells immobilized. The results point out that in spite of showing the lowest WAI and intermediate λ, raw material was the most appropriated substrate to conduct the bioconversion, achieving up to 262.9 mg/L phenolic compounds after 24 h, corresponding to 42.9 mg/L vanillin, 115.6 mg/L vanillyl alcohol, and 104.4 mg/L vanillic acid. The results showed the potential of this process to be applied for biotechnological production of vanillin from ferulic acid solutions; however, further studies must be carried out to increase vanillin yield. Additionally, the liquors obtained after treatment of vine-trimming wastes could be assayed to replace synthetic ferulic acid.

Safety and efficacy of early carotid artery stenting in patients with symptomatic stenosis.

BACKGROUND: Symptomatic carotid artery stenosis is a significant contributor to ischemic strokes. Carotid artery stenting (CAS) is usually indicated for secondary stroke prevention. This study evaluates the safety and efficacy of CAS performed within a short time frame from symptom onset. METHODS: We conducted a single-center, retrospective study of consecutive patients who underwent CAS for symptomatic carotid stenosis within eight days of symptom onset from July 2019 to January 2022. Data on demographics, medical history, procedural details, and follow-up outcomes were analyzed. The primary outcome measure was the recurrence of the stroke within the first month post-procedure. Secondary outcomes included mortality, the rate of intra-procedural complications, and hyperperfusion syndrome. RESULTS: We included 93 patients with a mean age of 71.7 ± 11.7 years. The median time from symptom onset to CAS was 96 h. The rate of stroke recurrence was 5.4% in the first month, with a significant association between the number of stents used and increased recurrence risk. Mortality within the first month was 3.2%, with an overall mortality rate of 11.8% after a median follow-up of 19 months. Intra-procedural complications were present in five (5.4%) cases and were related to the number of stents used (p = 0.002) and post-procedural angioplasty (p = 0.045). Hyperperfusion syndrome occurred in 3.2% of cases. CONCLUSION: Early CAS within the high-risk window post-symptom onset is a viable secondary stroke prevention strategy in patients with symptomatic carotid artery stenosis. The procedure rate of complication is acceptable, with a low recurrence of stroke. However, further careful selection of patients for this procedural strategy is crucial to optimize outcomes.

Whole blood RNA signatures in tuberculosis patients receiving H56:IC31 vaccine as adjunctive therapy.

Introduction: Therapeutic vaccination in tuberculosis (TB) represents a Host Directed Therapy strategy which enhances immune responses in order to improve clinical outcomes and shorten TB treatment. Previously, we have shown that the subunit H56:IC31 vaccine induced both humoral and cellular immune responses when administered to TB patients adjunctive to standard TB treatment (TBCOX2 study, NCT02503839). Here we present the longitudinal whole blood gene expression patterns in H56:IC31 vaccinated TB patients compared to controls receiving standard TB treatment only. Methods: The H56:IC31 group (N=11) and Control group (N=7) underwent first-line TB treatment for 182 days. The H56:IC31 group received 5 micrograms of the H56:IC31 vaccine (Statens Serum Institut; SSI, Valneva Austria GmbH) intramuscularly at day 84 and day 140. Total RNA was extracted from whole blood samples collected in PAXgene tubes on days 0, 84, 98, 140, 154, 182 and 238. The expression level of 183 immune-related genes was measured by high-throughput microfluidic qPCR (Biomark HD system, Standard BioTools). Results: The targeted gene expression profiling unveiled the upregulation of modules such as interferon (IFN) signalling genes, pattern recognition receptors and small nucleotide guanosine triphosphate (GTP)-ases in the vaccinated group compared to controls two weeks after administration of the first H56:IC31 vaccine. Additionally, the longitudinal analysis of the Adolescent Cohort Study-Correlation of Risk (ACS-COR) signature showed a progressive downregulation in both study arms towards the end of TB treatment, in congruence with reported treatment responses and clinical improvements. Still, two months after the end of TB treatment, vaccinated patients, and especially those developing both cellular and humoral vaccine responses, showed a lower expression of the ACS-COR genes compared to controls. Discussion: Our data report gene expression patterns following H56:IC31 vaccination which might be interpreted as a lower risk of relapse in therapeutically vaccinated patients. Further studies are needed to conclude if these gene expression patterns could be used as prognostic biosignatures for therapeutic TB vaccine responses.

Characteristics of a Lipid Hydrogel and Bigel as Matrices for Ascorbic Acid Stabilization.

Ascorbic acid (AA) has many health benefits, including immune and cardiovascular deficiency protection, prenatal problems, and skin diseases. Unfortunately, AA is easily oxidized and has limited bioavailability. Thus, the development of formulations that stabilize and enhance the efficacy of AA is a challenge. In this study, 4% AA was encapsulated in two recently developed gels, a hydrogel and a bigel. The hydrogel was formed exclusively with lipids and water, and the bigel was a combination of the hydrogel with an oleogel formed with olive oil and beeswax. The effect of AA in gel microstructures was determined using X-ray scattering, rheology, and texture analysis. Additionally, the capacity of these materials to protect AA from degradation upon temperature and sunlight was studied. Results showed that the incorporation of AA into both materials did not affect their microstructure. Moreover, hydrogel-protected AA showed only 2% degradation after three months at 8 °C, while in aqueous solution, it degraded by 12%. Regarding sunlight, bigel showed a good shielding effect, exhibiting only 2% AA degradation after 22 h of exposure, whereas in aqueous solution, AA degraded by 10%. These results suggest that both proposed gels could be used in biomedical applications and the field of food.

A biocompatible lipid-based bigel for topical applications.

The development of biocompatible delivery systems is a necessity for medical and topical applications. Herein, the development of a new bigel for topical application is described. It is composed of 40% colloidal lipid hydrogel and 60% olive oil and beeswax oleogel. Its characterization and the potential of the bigel as a drug carrier through the skin was evaluated in vitro using fluorescence microscopy and two phases of the bigel were labeled with two fluorescent probes: sodium fluorescein (hydrophilic phase) and Nile red (lipophilic phase). The structure of the bigel showed two phases with fluorescence microscopy in which the hydrogel phase was incorporated into a continuous oleogel matrix. Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) presented a combination of vibrations characteristic of the different molecules forming the bigel, and Differential Scanning Calorimetry (DSC) showed different transitions attributed to beeswax lipids. Small-angle and wide-angle X-ray scattering (SAXS and WAXS) indicated a predominant lamellar structure with orthorhombic lateral packing that could be related to the arrangement of beeswax crystals. Bigel enables deeper penetration of hydrophilic and lipophilic probes into deeper layers, making it a promising candidate for effective topical carriers in medical and dermatological applications.

Echocardiographic Assessment of the Pulmonary Vein to Pulmonary Artery Ratio in Canine Heartworm Disease.

Background:Dirofilaria immitis produces proliferative pulmonary endarteritis and pulmonary thromboembolism in infected dogs. The pulmonary vascular lesions lead to irreversible and persistent structural damage and, as a consequence, sustained precapillary pulmonary hypertension (PH). The purpose of this study was to assess the diagnostic value of the pulmonary vein to pulmonary artery ratio (PV:PA ratio) to determine moderate or severe PH (>50 mmHg) in dogs with heartworm disease. METHODS: A total of 151 naturally heartworm-infected and 66 healthy dogs were included in the study. The presence/absence of PH was based on the right pulmonary artery distensibility index (RPAD index < 29.5%), and the PV:PA ratio was echocardiographically measured by the time-motion mode (M mode) and two-dimensional mode (2D mode). Other echocardiographic parameters were also assessed (pulmonary trunk to aorta ratio, tricuspid regurgitation pressure gradient, and AT:ET ratio). RESULTS: The results of the PV:PA ratio showed a highly positive correlation between the M and 2D modes (r = 0.928). The PV:PA ratio obtained by the M mode was identified as the strongest predictor for RPAD index (R2 0.628, p < 0.0001) with a good diagnostic accuracy (AUC = 0.99). The results of PV/PA by the 2D mode showed a similar prediction for the RPAD index (R2 0.606, p < 0.0001) with a good diagnostic accuracy (AUC = 0.98). Both of the 2D and M modes' PV:PA ratios decreased significantly with the presence of PH. A cut-off value of ≤0.845 showed high sensitivity and specificity for the M mode (97% and 94%, respectively) and the 2D mode (96% and 93%, respectively). CONCLUSIONS: The PV:PA ratio may be useful as a complementary diagnostic method for the estimation of moderate or severe PH in dogs with heartworm.

Usefulness of Tissue Doppler Imaging for the Evaluation of Pulmonary Hypertension in Canine Heartworm Disease.

BACKGROUND: Dirofilaria immitis is a nematode that produces proliferative pulmonary endarteritis in dogs due to direct contact of the adult parasites with the intima layer of the pulmonary arteries, leading to irreversible severe structural damage and sustained pulmonary hypertension (PH), which can produce severe cardiorespiratory disorders. The purpose of this study was to assess the diagnostic value of the echocardiography tissue Doppler imaging (TDI) in determining the presence of PH in dogs with heartworm disease. METHODS: There were 116 heartworm-infected dogs with PH and 33 healthy dogs included in the study. Based on the right pulmonary artery distensibility index (RPADi) < 29.5%, PH was present in 47.4% of infected dogs. Additionally, the animals were evaluated using other standard alternative echocardiographic measures to estimate PH. Moreover, a total of eight echocardiographic measurements were analysed using the TDI to determine its usefulness in diagnosing PH (E', A', S, E':A', global TDI, HRI-IVCT, HRI-IVRT, R-TEI). RESULTS: The TDI measurements showed significant differences between dogs with and without PH, demonstrating a positive correlation with respect to the RPADi. In addition, cut-off values for the detection of PH with excellent sensitivity and specificity were found for E':A', global TDI, HRI-IVCT, HRI-IVRT and R-TEI. CONCLUSIONS: The TDI mode may be useful as an adjunct diagnostic method for the determination of PH in dogs with Dirofilaria immitis.

Usefulness of NT-proBNP in dogs with heartworm: could this biomarker be useful to evaluate pulmonary hypertension?

BACKGROUND: In recent years, the usefulness of echocardiography and serum biomarkers in the diagnosis of pulmonary hypertension (PH) in dogs with heartworm disease has been studied. Previously, N-terminal pro B-type natriuretic peptide (NT-proBNP) has shown high concentrations in dogs with heart disease and/or PH as well as its usefulness as a prognostic indicator, but it has never been evaluated in the diagnosis and prognosis of PH in dogs with heartworm disease. The aim was to evaluate the serum concentrations of NT-proBNP in dogs infected by Dirofilaria immitis to determine its usefulness as a tool to detect precapillary PH. METHODS: NT-proBNP was determined in 50 heartworm-infected dogs. Presence/absence of PH was determined echocardiographically, using the Right Pulmonary Artery Distensibility Index (RPAD Index) and the systolic flow of tricuspid regurgitation mainly, together with other echocardiographic measurements following the guidelines of the American College of Veterinary Internal Medicine (ACVIM) for the diagnosis of PH. Other epidemiological parameters (breed, age, sex, status: client-owned or shelter dogs) and clinical parameters (microfilaremia, parasite burden, presence of symptoms, body condition) were collected as well. RESULTS: Moderate-severe PH was present in 40% of the dogs (RPAD Index < 29.5%), NT-proBNP concentrations being significantly higher compared with dogs that did not have PH. A cutoff for NT-proBNP of ≥ 1178.45 pmol/l showed a sensitivity of 64.3% and a specificity of 95.5% for the presence of moderate-severe PH. Older dogs and dogs from shelters showed significantly higher NT-proBNP concentrations. Dogs with symptoms and low body condition presented significantly higher NT-proBNP concentrations as well. CONCLUSIONS: The determination of NT-pro-BNP concentration can be a useful tool in the diagnostic work-up of dogs with heartworm disease and associated PH and can help to identify animals in the more advanced stage of this disorder.

Feline heartworm disease and environmental allergens hypersensitivity: is there a link?

BACKGROUND: Cats can be infected by Dirofilaria immitis, the causative agent of heartworm disease, characterized by respiratory signs, airway hyperreactivity, remodelling and inflammation. Allergy is a multifactorial pathology, and the role of a number of helminth parasites in the development of allergies in humans and other species has been demonstrated in many studies. The aim of the present study was to verify whether cats seropositive for D. immitis present hypersensitivity to some environmental allergens. METHODS: Blood samples were collected from 120 cats and tested for the presence of specific immunoglobulin G antibodies against D. immitis and for hypersensitivity to 20 allergens, using commercial allergen test kits. RESULTS: Of the 120 cats tested, 72 (60.0%) were seropositive for anti-D. immitis IgG and 55 (45.8%) showed clinical signs of heartworm disease of a respiratory nature. The results of testing with the allergen kits showed that 50.8% of cats were seropositive for ≥ 1 allergens, with the most common allergens being Dermatophagoides farinae (25.8%), Dermatophagoides pteronyssinus (20.0%), Malassezia (17.5%) and Ctenocephalides felis (14.2%). The prevalence of allergies was significantly higher-by almost threefold-in cats seropositive for D. immitis (68.1% vs. 25%). There were no significant differences between the prevalence of allergic cats and presence/absence of symptoms, and the results confirmed that symptoms were not a decisive factor for the presence of allergies. The risk for developing allergies was 6.3-fold higher in cats seropositive for D. immitis than in cats that were seronegative, confirming that seropositivity for D. immitis is a risk factor. CONCLUSIONS: Cats with confirmed heartworm can develop serious respiratory signs, potentially leading to progression to permanent lung injury and predisposing cats to hyperresponsive airway disease. Previous studies have shown that seropositivity for D. immitis and Wolbachia is related to the presence of bronchoconstriction and bronchospasm in the affected cat. The results support the suspicion that contact with D. immitis may be a risk factor for the presence of allergies.

Right Ventricle Strain Assessed by 2-Dimensional Speckle Tracking Echocardiography (2D-STE) to Evaluate Pulmonary Hypertension in Dogs with Dirofilaria immitis.

Echocardiographic assessment of the right ventricle is helpful for analysing the pathophysiology of heartworm disease and detecting pulmonary hypertension (PH) in dogs. In veterinary cardiology, the study of myocardial deformation using two-dimensional speckle tracking (2D-STE) echocardiography has become increasingly acknowledged as useful for quantifying right ventricular function. The aim of this study was to evaluate the usefulness of myocardial deformation strain of the right ventricular free wall (FWS), global deformation strain of the right ventricle, including the interventricular septum (GS), and tissue motion annular displacement of the tricuspid valve (TMAD) in a cohort of dogs with heartworm (Dirofilaria immitis) disease and to determine cut-off values for detecting the presence of PH. Out of the 93 dogs tested, 71% were diagnosed with heartworm infection. PH was identified in 41% of the infected dogs following the American College of Veterinary Internal Medicine (ACVIM) guidelines, based on the peak tricuspid regurgitation velocity to calculate the tricuspid regurgitation pressure gradient (TRPG), while other routine measurements were used, including the right pulmonary artery distensibility index (RPADi). The 2D-STE mode measurements were determined using Right Ventricular Automated Function Imaging (RV AFI®) software. The statistical analysis showed significant differences in the studied parameters among dogs with and without PH. Additionally, sensitivity (sen) and specificity (sp) cut-off values were obtained (GS ≥ -21.25%, sen 96%, sp 86.4%; FWS ≥ -21.95%, sen 92.56%, sp 95.5%; TMAD ≤ 0.85 cm, sen 70.4%, sp 83.3%). These results demonstrated that GS, FWS, and TMAD could be used as supplementary and alternative variables to conventional echocardiographic measurements when detecting PH in dogs with heartworm disease.

Effect of an Immune-Boosting, Antioxidant and Anti-Inflammatory Food Supplement in Hospitalized COVID-19 Patients: A Prospective Randomized Pilot Study.

BACKGROUND: COVID-19 disease is a serious global health problem. Few treatments have been shown to reduce mortality and accelerate time to recovery. The aim of this study was to evaluate the potential effect of a food supplement (probiotics, prebiotics, vitamin D, zinc and selenium) in patients admitted with COVID-19. METHODS: A prospective randomized non-blinded clinical trial was conducted in a sample of 162 hospitalized patients diagnosed with COVID-19 recruited over eight months. All patients received standard treatment, but the intervention group (n = 67) was given one food supplement stick daily during their admission. After collecting the study variables, a statistical analysis was performed comparing the intervention and control groups and a multivariate analysis controlling for variables that could act as confounding factors. RESULTS: ROC curve analysis with an area under the curve (AUC) value of 0.840 (p < 0.001; 95%CI: 0.741-0.939) of the food supplement administration vs. recovery indicated good predictive ability. Moreover, the intervention group had a shorter duration of digestive symptoms compared with the control group: 2.6 ± 1.3 vs. 4.3 ± 2.2 days (p = 0.001); patients with non-severe disease on chest X-ray had shorter hospital stays: 8.1 ± 3.9 vs. 11.6 ± 7.4 days (p = 0.007). CONCLUSIONS: In this trial, the administration of a food supplement (Gasteel Plus®) was shown to be a protective factor in the group of patients with severe COVID-19 and allowed early recovery from digestive symptoms and a shorter hospital stay in patients with a normal-mild-moderate chest X-ray at admission (ClinicalTrials.gov number, NCT04666116).

Π-Π interactions stabilize PeptoMicelle-based formulations of Pretomanid derivatives leading to promising therapy against tuberculosis in zebrafish and mouse models.

Tuberculosis is the deadliest bacterial disease globally, threatening the lives of millions every year. New antibiotic therapies that can shorten the duration of treatment, improve cure rates, and impede the development of drug resistance are desperately needed. Here, we used polymeric micelles to encapsulate four second-generation derivatives of the antitubercular drug pretomanid that had previously displayed much better in vivo activity against Mycobacterium tuberculosis than pretomanid itself. Because these compounds were relatively hydrophobic and had limited bioavailability, we expected that their micellar formulations would overcome these limitations, reduce toxicities, and improve therapeutic outcomes. The polymeric micelles were based on polypept(o)ides (PeptoMicelles) and were stabilized in their hydrophobic core by π-π interactions, allowing the efficient encapsulation of aromatic pretomanid derivatives. The stability of these π-π-stabilized PeptoMicelles was demonstrated in water, blood plasma, and lung surfactant by fluorescence cross-correlation spectroscopy and was further supported by prolonged circulation times of several days in the vasculature of zebrafish larvae. The most efficacious PeptoMicelle formulation tested in the zebrafish larvae infection model almost completely eradicated the bacteria at non-toxic doses. This lead formulation was further assessed against Mycobacterium tuberculosis in the susceptible C3HeB/FeJ mouse model, which develops human-like necrotic granulomas. Following intravenous administration, the drug-loaded PeptoMicelles significantly reduced bacterial burden and inflammatory responses in the lungs and spleens of infected mice.

Measuring cognitive impairment and monitoring cognitive decline in Huntington's disease: a comparison of assessment instruments.

BACKGROUND: Progressive cognitive decline is an inevitable feature of Huntington's disease (HD) but specific criteria and instruments are still insufficiently developed to reliably classify patients into categories of cognitive severity and to monitor the progression of cognitive impairment. METHODS: We collected data from a cohort of 180 positive gene-carriers: 33 with premanifest HD and 147 with manifest HD. Using a specifically developed gold-standard for cognitive status we classified participants into those with normal cognition, those with mild cognitive impairment, and those with dementia. We administered the Parkinson's Disease-Cognitive Rating Scale (PD-CRS), the MMSE and the UHDRS cogscore at baseline, and at 6-month and 12-month follow-up visits. Cutoff scores discriminating between the three cognitive categories were calculated for each instrument. For each cognitive group and instrument we addressed cognitive progression, sensitivity to change, and the minimally clinical important difference corresponding to conversion from one category to another. RESULTS: The PD-CRS cutoff scores for MCI and dementia showed excellent sensitivity and specificity ratios that were not achieved with the other instruments. Throughout follow-up, in all cognitive groups, PD-CRS captured the rate of conversion from one cognitive category to another and also the different patterns in terms of cognitive trajectories. CONCLUSION: The PD-CRS is a valid and reliable instrument to capture MCI and dementia syndromes in HD. It captures the different trajectories of cognitive progression as a function of cognitive status and shows sensitivity to change in MCI and dementia.

Effect of nutrient supplementation of crude or detoxified concentrated distilled grape marc hemicellulosic hydrolysates on the xylitol production by Debaryomyces hansenii.

Biosynthesis of xylitol using the yeast Debaryomyces hansenii NRRL Y-7426 was carried out using distilled grape marc (DGM) hemicellulosic hydrolysates directly concentrated by vacuum evaporation or after detoxification with activated charcoal. The effect of nutrient supplementation with vinasses, corn steep liquor (CSL) or commercial nutrients was explored. Using crude concentrated hemicellulosic hydrolysates, the maximum xylitol concentration, 11.3 g/L, was achieved after 172 hr (Q ( xylitol ) = 0.066 g/L-hr; Y ( xylitol ) (/SC) = 0.21 g/g); meanwhile, using detoxified concentrated hydrolysates, the concentration increased up to 19.7 g/L after 72 hr (Q ( xylitol ) = 0.274 g/L-hr; Y ( xylitol ) (/SC) = 0.38 g/g). On the other hand, using crude or detoxified hydrolysates, the xylose-to-xylitol bioconversion was strongly affected by the addition of nutrients, suggesting that these hydrolysates present essential nutrients favouring the growth of D. hansenii.

PCR-hybridization after sonication improves diagnosis of implant-related infection.

PURPOSE: We wanted to improve the diagnosis of implant-related infection using molecular biological techniques after sonication. METHODS: We studied 258 retrieved implant components (185 prosthetic implants and 73 osteosynthesis implants) from 126 patients. 47 patients had a clinical diagnosis of infection (108 components) and 79 patients did not (150 components). The fluids from sonication of retrieved implants were tested in culture and were also analyzed using a modified commercial PCR kit for detection of Gram-positive and Gram-negative bacteria (GenoType BC; Hain Lifescience) after extraction of the DNA. RESULTS: 38 of 47 patients with a clinical diagnosis of infection were also diagnosed as being infected using culture and/or PCR (35 by culture alone). Also, 24 patients of the 79 cases with no clinical diagnosis of infection were identified microbiologically as being infected (4 by culture, 16 by PCR, and 4 by both culture and PCR). Comparing culture and PCR, positive culture results were obtained in 28 of the 79 patients and positive PCR results were obtained in 35. There were 21 discordant results in patients who were originally clinically diagnosed as being infected and 28 discordant results in patients who had no clinical diagnosis of infection. INTERPRETATION: For prosthetic joint infections and relative to culture, molecular detection can increase (by one tenth) the number of patients diagnosed as having an infection. Positive results from patients who have no clinical diagnosis of infection must be interpreted carefully.