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1.
Biomaterials ; 313: 122814, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39243672

RESUMEN

Radiotherapy as a mainstay of in-depth cervical cancer (CC) treatment suffers from its radioresistance. Radiodynamic therapy (RDT) effectively reverses radio-resistance by generating reactive oxygen species (ROS) with deep tissue penetration. However, the photosensitizers stimulated by X-ray have high toxicity and energy attenuation. Therefore, X-ray responsive diselenide-bridged mesoporous silica nanoparticles (DMSNs) are designed, loading X-ray-activated photosensitizer acridine orange (AO) for spot blasting RDT like Trojan-horse against radio-resistance cervical cancer (R-CC). DMSNs can encapsulate a large amount of AO, in the tumor microenvironment (TME), which has a high concentration of hydrogen peroxide, X-ray radiation triggers the cleavage of diselenide bonds, leading to the degradation of DMSNs and the consequent release of AO directly at the tumor site. On the one hand, it solves the problems of rapid drug clearance, adverse distribution, and side effects caused by simple AO treatment. On the other hand, it fully utilizes the advantages of highly penetrating X-ray responsive RDT to enhance radiotherapy sensitivity. This approach results in ROS-induced mitochondria damage, inhibition of DNA damage repair, cell cycle arrest and promotion of cancer cell apoptosis in R-CC. The X-ray responsive DMSNs@AO hold considerable potential in overcoming obstacles for advanced RDT in the treatment of R-CC.


Asunto(s)
Nanopartículas , Dióxido de Silicio , Humanos , Animales , Rayos X , Nanopartículas/química , Femenino , Dióxido de Silicio/química , Ratones , Neoplasias del Cuello Uterino/terapia , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/patología , Especies Reactivas de Oxígeno/metabolismo , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Tolerancia a Radiación/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacos , Ratones Desnudos , Células HeLa , Ratones Endogámicos BALB C , Apoptosis/efectos de los fármacos , Línea Celular Tumoral
2.
J Vis ; 24(9): 14, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39302649

RESUMEN

The eye has considerable chromatic aberration, meaning that the accommodative demand varies with wavelength. Given this, how does the eye accommodate to light of differing spectral content? Previous work is not conclusive but, in general, the eye focuses in the center of the visible spectrum for broadband light, and it focuses at a distance appropriate for individual wavelengths for narrowband light. For stimuli containing two colors, there are also mixed reports. This is the second of a series of two papers where we investigate accommodation in relation to chromatic aberration Fernandez-Alonso, Finch, Love, and Read (2024). In this paper, for the first time, we measure how the eye accommodates to images containing two narrowband wavelengths, with varying relative luminance under monocular conditions. We find that the eye tends to accommodate between the two extremes, weighted by the relative luminance. At first sight, this seems reasonable, but we show that image quality would be maximized if the eye instead accommodated on the more luminous wavelength. Next we explore several hypotheses as to what signal the eye might be using to drive accommodation and compare these with the experimental data. We show that the data is best explained if the eye seeks to maximize contrast at low spatial frequencies. We consider the implication of these results for both the mechanism behind accommodation, and for modern displays containing narrowband illuminants.


Asunto(s)
Acomodación Ocular , Estimulación Luminosa , Acomodación Ocular/fisiología , Humanos , Estimulación Luminosa/métodos , Adulto , Masculino , Percepción de Color/fisiología , Femenino , Adulto Joven , Visión Monocular/fisiología
3.
Immunogenetics ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39294478

RESUMEN

The inbred Babraham pig serves as a valuable biomedical model for research due to its high level of homozygosity, including in the major histocompatibility complex (MHC) loci and likely other important immune-related gene complexes, which are generally highly diverse in outbred populations. As the ability to control for this diversity using inbred organisms is of great utility, we sought to improve this resource by generating a long-read whole genome assembly and transcriptome atlas of a Babraham pig. The genome was de novo assembled using PacBio long reads and error-corrected using Illumina short reads. Assembled contigs were then mapped to the porcine reference assembly, Sscrofa11.1, to generate chromosome-level scaffolds. The resulting TPI_Babraham_pig_v1 assembly is nearly as contiguous as Sscrofa11.1 with a contig N50 of 34.95 Mb and contig L50 of 23. The remaining sequence gaps are generally the result of poor assembly across large and highly repetitive regions such as the centromeres and tandemly duplicated gene families, including immune-related gene complexes, that often vary in gene content between haplotypes. We also further confirm homozygosity across the Babraham MHC and characterize the allele content and tissue expression of several other immune-related gene complexes, including the antibody and T cell receptor loci, the natural killer complex, and the leukocyte receptor complex. The Babraham pig genome assembly provides an alternate highly contiguous porcine genome assembly as a resource for the livestock genomics community. The assembly will also aid biomedical and veterinary research that utilizes this animal model such as when controlling for genetic variation is critical.

4.
Biomed Opt Express ; 15(9): 5053-5066, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39296386

RESUMEN

We present a novel approach for deep vascular imaging in rodent cortex at excitation wavelengths susceptible to water absorption using two-photon microscopy with photons of dissimilar wavelengths. We demonstrate that non-degenerate two-photon excitation (ND-2PE) enables imaging in the water absorption window from 1400-1550 nm using two excitation sources with temporally overlapped pulses at 1300 nm and 1600 nm that straddle the absorption window. We explore the brightness spectra of indocyanine green (ICG) and assess its suitability for imaging in the water absorption window. Further, we demonstrate in vivo imaging of the rodent cortex vascular structure up to 1.2 mm using ND-2PE. Lastly, a comparative analysis of ND-2PE at 1435 nm and single-wavelength, two-photon imaging at 1300 nm and 1435 nm is presented. Our work extends the excitation range for fluorescent dyes to include water absorption regimes and underscores the feasibility of deep two-photon imaging at these wavelengths.

5.
Am J Hum Genet ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39299239

RESUMEN

Hereditary hemorrhagic telangiectasia (HHT) is an inherited disorder of vascular malformations characterized by mucocutaneous telangiectases and arteriovenous malformations (AVMs) in internal organs. HHT is caused by inheritance of a loss of function mutation in one of three genes. Although individuals with HHT are haploinsufficient for one of these genes throughout their entire body, rather than exhibiting a systemic vascular phenotype, vascular malformations occur as focal lesions in discrete anatomic locations. The inconsistency between genotype and phenotype has provoked debate over whether haploinsufficiency or a different mechanism gives rise to the vascular malformations. We previously showed that HHT-associated skin telangiectases develop by a two-hit mutation mechanism in an HHT gene. However, somatic mutations were identified in only half of the telangiectases, raising the question whether a second-hit somatic mutation is a necessary (required) event in HHT pathogenesis. Here, we show that another mechanism for the second hit is loss of heterozygosity across the chromosome bearing the germline mutation. Secondly, we investigate the two-hit mutation mechanism for internal organ AVMs, the source of much of the morbidity of HHT. Here, we identified somatic molecular genetic events in eight liver telangiectases, including point mutations and a loss of heterozygosity event. We also identified somatic mutations in one pulmonary AVM and two brain AVMs, confirming that mucocutaneous and internal organ vascular malformations undergo the same molecular mechanisms. Together, these data argue that bi-allelic loss of function in an HHT gene is a required event in the pathogenesis of HHT-associated vascular malformations.

6.
J Clin Invest ; 134(18)2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39286976

RESUMEN

CD8+ T cells destroy insulin-producing pancreatic ß cells in type 1 diabetes through HLA class I-restricted presentation of self-antigens. Combinatorial peptide library screening was used to produce a preferred peptide recognition landscape for a patient-derived T cell receptor (TCR) that recognized the preproinsulin-derived (PPI-derived) peptide sequence LWMRLLPLL in the context of disease risk allele HLA A*24:02. Data were used to generate a strong superagonist peptide, enabling production of an autoimmune HLA A*24:02-peptide-TCR structure by crystal seeding. TCR binding to the PPI epitope was strongly focused on peptide residues Arg4 and Leu5, with more flexibility at other positions, allowing the TCR to strongly engage many peptides derived from pathogenic bacteria. We confirmed an epitope from Klebsiella that was recognized by PPI-reactive T cells from 3 of 3 HLA A*24:02+ patients. Remarkably, the same epitope selected T cells from 7 of 8 HLA A*24+ healthy donors that cross-reacted with PPI, leading to recognition and killing of HLA A*24:02+ cells expressing PPI. These data provide a mechanism by which molecular mimicry between pathogen and self-antigens could have resulted in the breaking of self-tolerance to initiate disease.


Asunto(s)
Diabetes Mellitus Tipo 1 , Antígeno HLA-A24 , Insulina , Precursores de Proteínas , Receptores de Antígenos de Linfocitos T , Humanos , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/genética , Precursores de Proteínas/inmunología , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Insulina/inmunología , Insulina/metabolismo , Antígeno HLA-A24/inmunología , Antígeno HLA-A24/genética , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/genética , Epítopos de Linfocito T/inmunología , Epítopos de Linfocito T/genética , Linfocitos T CD8-positivos/inmunología , Femenino , Masculino
7.
bioRxiv ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39229231

RESUMEN

The precise onset of flowering is crucial to ensure successful plant reproduction. The gene FLOWERING LOCUS T (FT) encodes florigen, a mobile signal produced in leaves that initiates flowering at the shoot apical meristem. In response to seasonal changes, FT is induced in phloem companion cells located in distal leaf regions. Thus far, a detailed molecular characterization of the FT-expressing cells has been lacking. Here, we used bulk nuclei RNA-seq and single nuclei RNA (snRNA)-seq to investigate gene expression in FT-expressing cells and other phloem companion cells. Our bulk nuclei RNA-seq demonstrated that FT-expressing cells in cotyledons and in true leaves differed transcriptionally. Within the true leaves, our snRNA-seq analysis revealed that companion cells with high FT expression form a unique cluster in which many genes involved in ATP biosynthesis are highly upregulated. The cluster also expresses other genes encoding small proteins, including the flowering and stem growth inducer FPF1-LIKE PROTEIN 1 (FLP1) and the anti-florigen BROTHER OF FT AND TFL1 (BFT). In addition, we found that the promoters of FT and the genes co-expressed with FT in the cluster were enriched for the consensus binding motifs of NITRATE-INDUCIBLE GARP-TYPE TRANSCRIPTIONAL REPRESSOR 1 (NIGT1). Overexpression of the paralogous NIGT1.2 and NIGT1.4 repressed FT expression and significantly delayed flowering under nitrogen-rich conditions, consistent with NIGT1s acting as nitrogen-dependent FT repressors. Taken together, our results demonstrate that major FT-expressing cells show a distinct expression profile that suggests that these cells may produce multiple systemic signals to regulate plant growth and development.

8.
Sci Rep ; 14(1): 21028, 2024 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251630

RESUMEN

Novel stimulation methods are needed to overcome the limitations of contemporary cochlear implants. Optogenetics is a technique that confers light sensitivity to neurons via the genetic introduction of light-sensitive ion channels. By controlling neural activity with light, auditory neurons can be activated with higher spatial precision. Understanding the behaviour of opsins at high stimulation rates is an important step towards their translation. To elucidate this, we compared the temporal characteristics of auditory nerve and inferior colliculus responses to optogenetic, electrical, and combined optogenetic-electrical stimulation in virally transduced mice expressing one of two channelrhodopsins, ChR2-H134R or ChIEF, at stimulation rates up to 400 pulses per second (pps). At 100 pps, optogenetic responses in ChIEF mice demonstrated higher fidelity, less change in latency, and greater response stability compared to responses in ChR2-H134R mice, but not at higher rates. Combined stimulation improved the response characteristics in both cohorts at 400 pps, although there was no consistent facilitation of electrical responses. Despite these results, day-long stimulation (up to 13 h) led to severe and non-recoverable deterioration of the optogenetic responses. The results of this study have significant implications for the translation of optogenetic-only and combined stimulation techniques for hearing loss.


Asunto(s)
Vías Auditivas , Channelrhodopsins , Estimulación Eléctrica , Optogenética , Animales , Optogenética/métodos , Ratones , Vías Auditivas/fisiología , Vías Auditivas/metabolismo , Channelrhodopsins/metabolismo , Channelrhodopsins/genética , Estimulación Eléctrica/métodos , Colículos Inferiores/fisiología , Colículos Inferiores/metabolismo , Nervio Coclear/fisiología , Nervio Coclear/metabolismo , Cinética , Implantes Cocleares
9.
J Foot Ankle Res ; 17(3): e70000, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39223075

RESUMEN

INTRODUCTION: Midfoot osteoarthritis (OA) is a painful and disabling condition. Arch contouring foot orthoses have been recommended for midfoot OA, yet there is no high-quality evidence from randomised controlled trials to support their use. This clinical trial aims to evaluate the efficacy of arch contouring foot orthoses for midfoot OA. METHODS: This will be a parallel-group randomised controlled superiority trial. One-hundred and forty community-dwelling people with painful midfoot OA will be randomised to receive either arch contouring foot orthoses or flat sham inserts. Outcome measures will be obtained at baseline, 4, 8 and 12 weeks; the primary endpoint for assessing efficacy being 12 weeks. The primary outcome measure will be average midfoot pain whilst walking over the last 7 days on an 11-point numerical rating scale. Secondary outcome measures include function (walking/standing subscale of the Manchester-Oxford Foot Questionnaire), participants' perception of overall treatment effect (self-reported global rating of change on a 15-point Likert scale), physical activity (Incidental and Planned Exercise Questionnaire), general health-related quality of life (Short Form-12 Version® 2.0), use of co-interventions and adverse events. DISCUSSION: This trial will evaluate the efficacy of arch contouring foot orthoses for relieving pain and improving function, physical activity and health-related quality of life in people with midfoot OA. The findings will provide high-quality evidence as to whether arch contouring foot orthoses are efficacious and will help to inform clinical guidelines about the use of foot orthoses for midfoot OA. TRIAL REGISTRATION: Australian and New Zealand Clinical Trial Registry (ACTRN12623000953639).


Asunto(s)
Ortesis del Pié , Osteoartritis , Humanos , Osteoartritis/terapia , Osteoartritis/rehabilitación , Osteoartritis/complicaciones , Resultado del Tratamiento , Femenino , Persona de Mediana Edad , Masculino , Anciano , Calidad de Vida , Adulto , Ensayos Clínicos Controlados Aleatorios como Asunto , Caminata/fisiología
10.
Chem Biol Interact ; 403: 111242, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39265714

RESUMEN

In 2023, 3651 Ohioans died because of an opioid overdose. Of those opioid overdoses, 3579 (98%) of which were attributed to fentanyl. We evaluated the association between 180 candidate single nucleotide polymorphisms (SNPs) and self-reported, nonfatal opioid overdose history from a prospective sample of 1301 adult patients (≥18 years of age) seen in three urban emergency departments in Ohio. Candidate SNPs included 120 related to the dopamine reward pathway and 60 related to pharmacokinetics. Of the 821 patients who reported having been exposed to opioids in their lifetime, 95 (11.6%) also reported having experienced an opioid-related overdose. Logistic regression, adjusting for age and biologic sex, was used to characterize the association between each SNP and opioid overdose, correcting for multiple comparisons. Three SNPs, located in three different genes were associated with opioid overdose: increased odds with CYP3A5 (rs776746) and DRD2 (rs4436578), and decreased odds with NKIR (rs6715729). Homozygotic CYP3A5 (rs776746) had the highest adjusted odds ratio (OR) of 6.96 (95% CI [2.45, 29.23]) and homozygotic NK1R (rs6715729) had the lowest OR of 0.28 (95% CI [0.14, 0.54). Given that CYP3A5 (rs776746) has been associated with increased plasma concentrations of fentanyl, rs776746 could potentially be utilized as a prognostic risk indicator for the potential of an opioid overdose. NK1R regulates the expression of the neurokinin-1 receptor, a regulator of respiration and NK1R (rs6715729) represents a novel genetic marker for a decreased risk of opioid overdose risk.

11.
Eur J Med Chem ; 278: 116796, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39241483

RESUMEN

To achieve malaria eradication, new preventative agents that act differently to front-line treatment drugs are needed. To identify potential chemoprevention starting points we screened a sub-set of the CSIRO Australia Compound Collection for compounds with slow-action in vitro activity against Plasmodium falciparum. This work identified N,N-dialkyl-5-alkylsulfonyl-1,3,4-oxadiazol-2-amines as a new antiplasmodial chemotype (e.g., 1 96 h IC50 550 nM; 3 96 h IC50 160 nM) with a different action to delayed-death slow-action drugs. A series of analogues were synthesized from thiotetrazoles and carbomoyl derivatives using Huisgen 1,3,4-oxadiazole synthesis followed by oxidation of the resultant thioethers to target sulfones. Structure activity relationship analysis of analogues identified compounds with potent and selective in vitro activity against drug-sensitive and multi-drug resistant Plasmodium parasites (e.g., 31 and 32 96 h IC50 <40 nM; SI > 2500). Subsequent studies in mice with compound 1, which had the best microsomal stability of the compounds assessed (T1/2 >255 min), demonstrated rapid clearance and poor oral in vivo efficacy in a P. berghei murine malaria model. These data indicate that while N,N-dialkyl-5-alkylsulfonyl-1,3,4-oxadiazol-2-amines are a novel class of slow-acting antiplasmodial agents, the further development of this chemotype for malaria chemoprophylaxis will require pharmacokinetic profile improvements.


Asunto(s)
Antimaláricos , Oxadiazoles , Plasmodium falciparum , Oxadiazoles/química , Oxadiazoles/farmacología , Oxadiazoles/síntesis química , Plasmodium falciparum/efectos de los fármacos , Antimaláricos/farmacología , Antimaláricos/química , Antimaláricos/síntesis química , Animales , Relación Estructura-Actividad , Ratones , Pruebas de Sensibilidad Parasitaria , Estructura Molecular , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Humanos , Malaria Falciparum/tratamiento farmacológico
12.
J Neurosurg Spine ; : 1-8, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39270316

RESUMEN

OBJECTIVE: The long-term effects of increased body mass index (BMI) on surgical outcomes are unknown for patients who undergo surgery for low-grade lumbar spondylolisthesis. The goal of this study was to assess long-term outcomes in obese versus nonobese patients after surgery for grade 1 spondylolisthesis. METHODS: Patients who underwent surgery for grade 1 spondylolisthesis at the Quality Outcomes Database's 12 highest enrolling sites (SpineCORe group) were identified. Long-term (5-year) outcomes were compared for patients with BMI ≥ 35 versus BMI < 35. RESULTS: In total, 608 patients (57.6% female) were included. Follow-up was 81% (excluding patients who had died) at 5 years. The BMI ≥ 35 cohort (130 patients, 21.4%) was compared to the BMI < 35 cohort (478 patients, 78.6%). At baseline, patients with BMI ≥ 35 were more likely to be younger (58.5 ± 11.4 vs 63.2 ± 12.0 years old, p < 0.001), to present with both back and leg pain (53.8% vs 37.0%, p = 0.002), and to require ambulation assistance (20.8% vs 9.2%, p < 0.001). Furthermore, the cohort with BMI ≥ 35 had worse baseline patient-reported outcomes including visual analog scale (VAS) back (7.6 ± 2.3 vs 6.5 ± 2.8, p < 0.001) and leg (7.1 ± 2.6 vs 6.4 ± 2.9, p = 0.031) pain, disability measured by the Oswestry Disability Index (ODI) (53.7 ± 15.7 vs 44.8 ± 17.0, p < 0.001), and quality of life on EuroQol-5D (EQ-5D) questionnaire (0.47 ± 0.22 vs 0.56 ± 0.22, p < 0.001). Patients with BMI ≥ 35 were more likely to undergo fusion (85.4% vs 74.7%, p = 0.01). There were no significant differences in 30- and 90-day readmission rates (p > 0.05). Five years postoperatively, there were no differences in reoperation rates or the development of adjacent-segment disease for patients in either BMI < 35 or ≥ 35 cohorts who underwent fusion (p > 0.05). On multivariate analysis, BMI ≥ 35 was a significant risk factor for not achieving minimal clinically important differences (MCIDs) for VAS leg pain (OR 0.429, 95% CI 0.209-0.876, p = 0.020), but BMI ≥ 35 was not a predictor for achieving MCID for VAS back pain, ODI, or EQ-5D at 5 years postoperatively. CONCLUSIONS: Both obese and nonobese patients benefit from surgery for grade 1 spondylolisthesis. At the 5-year time point, patients with BMI ≥ 35 have similarly low reoperation rates and achieve rates of satisfaction and MCID for back pain (but not leg pain), disability (ODI), and quality of life (EQ-5D) that are similar to those in patients with a BMI < 35.

13.
J Neurosurg Spine ; : 1-7, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39270317

RESUMEN

OBJECTIVE: The aim of this study was to compare the rate of achievement of the minimal clinically important difference (MCID) in patient-reported outcomes (PROs) and satisfaction between cervical spondylotic myelopathy (CSM) patients with and without class III obesity who underwent surgery. METHODS: The authors analyzed patients from the 14 highest-enrolling sites in the prospective Quality Outcomes Database CSM cohort. Patients were dichotomized based on whether or not they were obese (class III, BMI ≥ 35 kg/m2). PROs including visual analog scale (VAS) neck and arm pain, Neck Disability Index (NDI), modified Japanese Orthopaedic Association (mJOA), EQ-5D, and North American Spine Society patient satisfaction scores were collected at baseline and 24 months after cervical spine surgery. RESULTS: Of the 1141 patients with CSM who underwent surgery, 230 (20.2%) were obese and 911 (79.8%) were not. The 24-month follow-up rate was 87.4% for PROs. Patients who were obese were younger (58.1 ± 12.1 years vs 61.2 ± 11.6 years, p = 0.001), more frequently female (57.4% vs 44.9%, p = 0.001), and African American (22.6% vs 13.4%, p = 0.002) and had a lower education level (high school or less: 49.1% vs 40.8%, p = 0.002) and a higher American Society of Anesthesiologists grade (2.7 ± 0.5 vs 2.5 ± 0.6, p < 0.001). Clinically at baseline, the obese group had worse neck pain (VAS score: 5.7 ± 3.2 vs 5.1 ± 3.3), arm pain (VAS score: 5.4 ± 3.5 vs 4.8 ± 3.5), disability (NDI score: 42.7 ± 20.4 vs 37.4 ± 20.7), quality of life (EQ-5D score: 0.54 ± 0.22 vs 0.56 ± 0.22), and function (mJOA score: 11.6 ± 2.8 vs 12.2 ± 2.8) (all p < 0.05). At the 24-month follow-up, however, there was no difference in the change in PROs between the two groups. Even after accounting for relevant covariates, no significant difference in achievement of MCID and satisfaction was observed between the two groups at 24 months. CONCLUSIONS: Despite the class III obese group having worse baseline clinical presentations, the two cohorts achieved similar rates of satisfaction and MCID in PROs. Class III obesity should not preclude and/or delay surgical management for patients who would otherwise benefit from surgery for CSM.

14.
Mol Neurobiol ; 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39271622

RESUMEN

Polygala paniculata L. is a native plant from tropical America. The therapeutic potential of the hydroalcoholic extract of P. paniculata (HEPp) has been scientifically explored due to folk medicine reports on its action against several afflictions. HEPp contains several bioactive molecules with neuroprotective activities, making it a promising candidate for stroke treatment. This study used electrophysiological, biochemical, and in vivo experiments to evaluate the molecular mechanisms underlying HEPp as a neuroprotective therapy for stroke targeting Pannexin-1 (Panx1). Panx1 is a non-selective channel that opens during ischemia and contributes to neuronal death. HEPp was not toxic to cortical neurons and pre-treatment with the extract reduced neuronal death promoted by oxygen and glucose deprivation in a dose-dependent manner. Additionally, HEPp blocked Panx1 currents in a dose-dependent manner and the effect, which was shown to be partially due to rutin. Animals submitted to photothrombosis and post-treated with HEPp had reduced infarct volume, and the effective dose was lower in males (1 mg/kg) than in females (10 mg/kg). On the other hand, in Panx1 KD mice (50% Panx1 levels), the acute treatment reduced the infarct volume only in males. Upon chronic treatment with HEPp, a reduction in Panx1 protein levels was observed. The current study provides reliable evidence of the neuroprotective properties of HEPp in both in vitro and in vivo models of stroke. The underlying mechanism involves, at least in part, the inhibition of Panx1 channel function and possibly downregulation of protein levels, suppressing the secondary events that lead to apoptosis and inflammation.

15.
Anal Chem ; 96(37): 14715-14719, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39229957

RESUMEN

Polymer conjugation has risen in importance over the past three decades as a means of increasing the in vivo half-life of biotherapeutics, with benefits including better stability, greater drug efficacy, and lower toxicity. However, the intrinsic variability of polymer synthesis results in products with broad distributions in chain length and branching structure, complicating quality control for successful functionalization and downstream conjugation. Frequently, a combination of several analytical techniques is required for comprehensive characterization. While liquid chromatography-mass spectrometry (LC-MS) is a powerful platform that can provide detailed molecular features of polymers, the mass spectra are inherently challenging to interpret due to high mass polydispersity and overlapping charge distributions. Here, by leveraging Fourier transform-based deconvolution and macromolecular mass defect analysis, we demonstrate a new way to streamline pharmaceutical polymer analysis, shedding light on polymer size, composition, branching, and end-group functionalization with the capability for reaction monitoring.


Asunto(s)
Análisis de Fourier , Espectrometría de Masas , Polímeros , Polímeros/química , Espectrometría de Masas/métodos , Cromatografía Liquida/métodos , Sustancias Macromoleculares/química , Peso Molecular , Cromatografía Líquida con Espectrometría de Masas
16.
Nat Commun ; 15(1): 8069, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39277599

RESUMEN

How intracellular bacteria subvert the major histocompatibility complex (MHC) class I pathway is poorly understood. Here, we show that the obligate intracellular bacterium Orientia tsutsugamushi uses its effector protein, Ank5, to inhibit nuclear translocation of the MHC class I gene transactivator, NLRC5, and orchestrate its proteasomal degradation. Ank5 uses a tyrosine in its fourth ankyrin repeat to bind the NLRC5 N-terminus while its F-box directs host SCF complex ubiquitination of NLRC5 in the leucine-rich repeat region that dictates susceptibility to Orientia- and Ank5-mediated degradation. The ability of O. tsutsugamushi strains to degrade NLRC5 correlates with ank5 genomic carriage. Ectopically expressed Ank5 that can bind but not degrade NLRC5 protects the transactivator during Orientia infection. Thus, Ank5 is an immunoevasin that uses its bipartite architecture to rid host cells of NLRC5 and reduce surface MHC class I molecules. This study offers insight into how intracellular pathogens can impair MHC class I expression.


Asunto(s)
Antígenos de Histocompatibilidad Clase I , Péptidos y Proteínas de Señalización Intracelular , Orientia tsutsugamushi , Orientia tsutsugamushi/metabolismo , Orientia tsutsugamushi/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Antígenos de Histocompatibilidad Clase I/metabolismo , Antígenos de Histocompatibilidad Clase I/genética , Animales , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Citoplasma/metabolismo , Células HEK293 , Proteolisis , Tifus por Ácaros/inmunología , Tifus por Ácaros/microbiología , Tifus por Ácaros/metabolismo , Ratones , Ubiquitinación , Interacciones Huésped-Patógeno/inmunología
17.
Health Technol Assess ; 28(40): 1-44, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-39239933

RESUMEN

Background: Second trimester miscarriage and preterm birth is a significant global problem. Surgical cervical cerclage is performed to prevent pregnancy loss and preterm birth. It utilises either a monofilament or braided suture. It is hypothesised that a braided material becomes colonised with pathogenic bacteria that causes vaginal dysbiosis, infection and cerclage failure. Objectives: The primary objective of the study was to examine the effectiveness of using a monofilament suture material as opposed to a braided suture material on pregnancy loss in women requiring a vaginal cervical cerclage. Design: Superiority open randomised controlled trial. Setting: Seventy-five maternity sites across the UK. Participants: Women experiencing a singleton pregnancy requiring a cervical cerclage. Interventions: Monofilament suture or braided suture. Main outcome measures: The primary outcome was pregnancy loss (miscarriage and perinatal mortality, including any stillbirth or neonatal death in the first week of life). Secondary outcomes included the core outcome set for preterm birth. Methods: Women were randomised on a 1 : 1 basis to monofilament or braided cerclage utilising a bespoke randomisation service with minimisation dependent on the site, indication for cerclage, intention to use progesterone and planned surgical technique. The inclusion criteria were three or more previous mid-trimester losses or preterm births, insertion of a cerclage in a previous pregnancy, a history of a mid-trimester loss or preterm birth with a shortened cervical length in the current pregnancy or in women who clinicians deemed at risk of preterm birth. The exclusion criteria were an emergency or rescue cerclage, age of < 18 years, being unable to give informed consent or the cerclage having to be placed abdominally. The original sample size was calculated based on a relative risk reduction of 41% from a pregnancy loss rate of 19% in the braided group to 11% in the monofilament group with 90% power and alpha at p = 0.05. The independent data monitoring committee noted a lower-than-anticipated pooled event rate within the trial and recommended an increase in sample size to 2050. The outcome data were collected using clinical record forms from the maternal and neonatal medical records and reported to Birmingham Clinical Trials Unit. Results: A total of 2049 women were randomised, after withdrawals and loss to follow-up, data on 1005 women in the monofilament group and 993 women in the braided group were included. The baseline demographics between the groups were similar. There was no evidence of a difference in pregnancy loss rates between the monofilament and braided groups (80/1003 vs. 75/993; adjusted risk ratio: 1.05, 95% confidence interval: 0.79 to 1.40; adjusted risk difference: 0.002, 95% confidence interval: -0.02 to 0.03). Limitations: The trial did not collect long-term paediatric outcomes. There were no safety concerns. Conclusions: There was no evidence of a difference in pregnancy loss between a monofilament suture and a braided suture. Future work: Long-term follow-up of neonates born within the C-STICH (cerclage suture type for an insufficient cervix and its effects on health outcomes) trial. Trial registration: This trial is registered as ISRCTN15373349. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 13/04/107) and is published in full in Health Technology Assessment; Vol. 28, No. 40. See the NIHR Funding and Awards website for further award information.


Cervical cerclage is an operation performed in pregnancy to prevent miscarriage and preterm birth. A cervical cerclage is sometimes recommended in women who have had babies born prematurely before or who have had previous cervical surgery. A cerclage operation involves a stitch being inserted around the neck of the womb (cervix) to keep it closed during pregnancy and to prevent it opening prematurely. When performing the operation, the doctor can use different types of threads made of different materials. The threads used to perform the operation are called sutures. One suture type is a single strand or monofilament thread, and the other is a multifilament braided thread with lots of thin strands woven together. Some evidence has suggested that using a monofilament suture thread prevented pregnancy loss by preventing infection. Therefore, we performed a randomised controlled trial of the use of monofilament suture thread versus braided suture thread, aiming to reduce pregnancy loss in women who were having a cerclage as part of their routine care. The women consented to take part in the study and were randomly allocated to their cerclage performed with either a monofilament or braided suture thread; there was no other change to their planned pregnancy care. What happened in their pregnancy was recorded from their medical records and analysed. A total of 2049 women agreed to take part in the study and consented to the analysis of their pregnancy and neonatal outcomes. Cerclage suture type for an insufficient cervix and its effects on health outcomes showed that there was no difference in pregnancy loss between the two suture threads. There was decreased maternal sepsis and decreased chorioamnionitis (which is an infection inside the womb during labour) in the women who received a monofilament suture, which needs further investigation. Although more women who had a cerclage using the monofilament thread needed a small operation and an anaesthetic, often between 36 and 37 weeks, to remove the monofilament suture prior to a vaginal birth, there were no differences in the outcomes for their babies.


Asunto(s)
Aborto Espontáneo , Cerclaje Cervical , Nacimiento Prematuro , Humanos , Femenino , Embarazo , Cerclaje Cervical/métodos , Adulto , Aborto Espontáneo/prevención & control , Nacimiento Prematuro/prevención & control , Reino Unido , Suturas , Técnicas de Sutura
19.
J Subst Use Addict Treat ; 167: 209506, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39265916

RESUMEN

INTRODUCTION: To assist the state of Ohio in addressing the opioid epidemic, the Ohio Attorney General appointed experts in a variety of academic disciplines to the Scientific Committee on Opioid Prevention and Education (SCOPE). The focus of SCOPE is the application of scientific principles to the development of prevention and educational strategies for reducing substance use disorder and related harms (e.g., promoting naloxone awareness). Naloxone awareness is a step in the naloxone cascade, which is a useful model for understanding the sequential steps laypeople must take to prepare themselves to intervene using naloxone; other steps include training and previous administration experience. Prior work has explored correlates of these steps among individuals with risky substance use, but fewer studies have focused on broader populations containing potential bystanders (e.g., family and community members). METHODS: This study was a secondary data analysis of patients from three urban emergency departments. Subsamples differed across five models (n = 479-1208) and included opioid-exposed and -naïve participants. Logistic regression characterized clinically useful sociodemographic predictors (e.g., race, ethnicity, education, employment, housing status) of naloxone awareness, self-efficacy (which relates to training), and previous-overdose administration. Two additional logistic regressions tested associations between risk factors for witnessing an opioid overdose and two cascade steps (awareness and self-efficacy). RESULTS: Non-White race, Hispanic ethnicity, and lower education predicted not being aware of naloxone; non-White race also predicted lower naloxone self-efficacy, and older age predicted lack of previous-overdose administration. Having family members with risky opioid use was heavily associated with awareness, while personal substance-use behaviors and previous overdose witnessing were associated with both awareness and higher naloxone self-efficacy. CONCLUSIONS: Characteristics associated with lower likelihood of completing each cascade step highlight opportunities for targeted interventions. Specifically, findings indicated the importance of expanding naloxone education and training programs to more diverse populations and to family members of individuals with risky opioid use. Further, these findings demonstrate how a state-funded program such as SCOPE can have a positive impact on identifying strategies that may assist in reducing mortality associated with opioid overdose.

20.
Int J Obstet Anesth ; 60: 104243, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39241680

RESUMEN

Cardiac arrhythmias are responsible for a significant portion of cardiovascular disease among pregnant people. As the incidence of arrhythmias in pregnancy continues to increase, anesthesiologists who care for obstetric patients should be experts managing arrhythmias in pregnancy. This article examines the most common arrhythmias encountered in pregnancy, including risk factors, diagnosis, and management strategies. Peripartum monitoring and labor analgesia recommendations are discussed. Additionally, management of cardioversion, management of pacemakers and implantable cardioverter-defibrillators, and advanced cardiac life support in the setting of pregnancy is reviewed.

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