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1.
Pain ; 2024 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-39446737

RESUMEN

ABSTRACT: The voltage-gated sodium channel NaV1.7 plays an important role in pain processing according to genetic data. Those data made NaV1.7 a popular drug target, especially since its relatively selective expression in nociceptors promised pain relief without the adverse effects associated with broader sodium channel blockade. Despite encouraging preclinical data in rodents, NaV1.7-selective inhibitors have not yet proven effective in clinical trials. Discrepancies between preclinical and clinical results should raise alarms. We reviewed preclinical and clinical reports on the analgesic efficacy of NaV1.7-selective inhibitors and found critical differences in several factors. Putting aside species differences, most preclinical studies tested young male rodents with limited genetic variability, inconsistent with the clinical population. Inflammatory pain was the most common preclinical chronic pain model whereas nearly all clinical trials focused on neuropathic pain despite some evidence suggesting NaV1.7 channels are not essential for neuropathic pain. Preclinical studies almost exclusively measured evoked pain whereas most clinical trials assessed average pain intensity without distinguishing between evoked and spontaneous pain. Nearly all preclinical studies gave a single dose of drug unlike the repeat dosing used clinically, thus precluding preclinical data from demonstrating whether tolerance or other slow processes occur. In summary, preclinical testing of NaV1.7-selective inhibitors aligned poorly with clinical testing. Beyond issues that have already garnered widespread attention in the pain literature, our results highlight the treatment regimen and choice of pain model as areas for improvement.

2.
Menopause ; 31(10): 926-939, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39081162

RESUMEN

ABSTRACT: Menopause, defined by the cessation of menstrual cycles after 12 months of amenorrhea not due to other causes, is associated with significant hormonal changes, primarily a decrease in estrogen, androgen, and progesterone levels. This review delves into the effects of estrogen deficiency during the perimenopausal transition and postmenopause, integrating the findings of basic science with clinical trials. Here, we first outline the variation in endogenous estrogens before and after menopause, exploring both genomic and nongenomic actions of estrogen and its estrogen receptors throughout the body. Next, we detail the spectrum of menopausal symptoms, from acute vasomotor, urogenital, and psychological issues during perimenopause to chronic reproductive, cardiovascular, neurological, skeletal, dermatologic, immune, and digestive changes postmenopause. Finally, we evaluate the role of hormone therapy in alleviating these symptoms, weighing its benefits against known risks. Publicizing these findings and an accurate representation of the risks and benefits of estrogen replacement to our aging patients is fundamental to improving their care, quality, and even quantity of life.


Asunto(s)
Terapia de Reemplazo de Estrógeno , Estrógenos , Menopausia , Humanos , Femenino , Estrógenos/deficiencia , Menopausia/fisiología , Ensayos Clínicos como Asunto
3.
RSC Appl Polym ; 2(3): 473-482, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38800515

RESUMEN

Glucagon is a peptide hormone that acts via receptor-mediated signaling predominantly in the liver to raise glucose levels by hepatic glycogen breakdown or conversion of noncarbohydrate, 3 carbon precursors to glucose by gluconeogenesis. Glucagon is administered to reverse severe hypoglycemia, a clinical complication associated with type 1 diabetes. However, due to low stability and solubility at neutral pH, there are limitations in the current formulations of glucagon. Trehalose methacrylate-based nanoparticles were utilized as the stabilizing and solubilizing moiety in the system reported herein. Glucagon was site-selectively modified to contain a cysteine at amino acid number 24 to covalently attach to the methacrylate-based polymer containing pyridyl disulfide side chains. PEG2000 dithiol was employed as the crosslinker to form uniform nanoparticles. Glucagon nanogels were monitored in Dulbecco's phosphate-buffered saline (DPBS) pH 7.4 at various temperatures to determine its long-term stability in solution. Glucagon nanogels were stable up to at least 5 months by size uniformity when stored at -20 °C and 4 °C, up to 5 days at 25 °C, and less than 12 hours at 37 °C. When glucagon stability was studied by either HPLC or thioflavin T assays, the glucagon was intact for at least 5 months at -20 °C and 4 °C within the nanoparticles at -20 °C and 4 °C and up to 2 days at 25 °C. Additionally, the glucagon nanogels were studied for toxicity and efficacy using various assays in vitro. The findings indicate that the nanogels were nontoxic to fibroblast cells and nonhemolytic to red blood cells. The glucagon in the nanogels was as active as glucagon alone. These results demonstrate the utility of trehalose nanogels towards a glucagon formulation with improved stability and solubility in aqueous solutions, particularly useful for storage at cold temperatures.

4.
Elife ; 122024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38687187

RESUMEN

Nociceptive sensory neurons convey pain-related signals to the CNS using action potentials. Loss-of-function mutations in the voltage-gated sodium channel NaV1.7 cause insensitivity to pain (presumably by reducing nociceptor excitability) but clinical trials seeking to treat pain by inhibiting NaV1.7 pharmacologically have struggled. This may reflect the variable contribution of NaV1.7 to nociceptor excitability. Contrary to claims that NaV1.7 is necessary for nociceptors to initiate action potentials, we show that nociceptors can achieve similar excitability using different combinations of NaV1.3, NaV1.7, and NaV1.8. Selectively blocking one of those NaV subtypes reduces nociceptor excitability only if the other subtypes are weakly expressed. For example, excitability relies on NaV1.8 in acutely dissociated nociceptors but responsibility shifts to NaV1.7 and NaV1.3 by the fourth day in culture. A similar shift in NaV dependence occurs in vivo after inflammation, impacting ability of the NaV1.7-selective inhibitor PF-05089771 to reduce pain in behavioral tests. Flexible use of different NaV subtypes exemplifies degeneracy - achieving similar function using different components - and compromises reliable modulation of nociceptor excitability by subtype-selective inhibitors. Identifying the dominant NaV subtype to predict drug efficacy is not trivial. Degeneracy at the cellular level must be considered when choosing drug targets at the molecular level.


Asunto(s)
Analgésicos , Bencenosulfonamidas , Nociceptores , Éteres Fenílicos , Animales , Analgésicos/farmacología , Nociceptores/metabolismo , Nociceptores/efectos de los fármacos , Canal de Sodio Activado por Voltaje NAV1.7/metabolismo , Canal de Sodio Activado por Voltaje NAV1.7/genética , Ratones , Potenciales de Acción/efectos de los fármacos , Dolor/tratamiento farmacológico , Humanos , Canales de Sodio/metabolismo , Canales de Sodio/genética , Canal de Sodio Activado por Voltaje NAV1.8/metabolismo , Canal de Sodio Activado por Voltaje NAV1.8/genética
5.
Colorectal Dis ; 25(12): 2335-2345, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37907449

RESUMEN

AIM: Slow laparoscopy adoption accelerated the uptake of robotic surgery. However, the current robotic platforms have limitations in transanal applications and multiple port sites. The da Vinci single-port (SP) robot is currently used on trial for colorectal surgery, and broad assessment of outcomes is needed. We aimed to report findings of a phase II clinical trial of SP robotic colorectal surgery. METHODS: A sequentially reported prospective case series was performed on patients using SP robotics at a tertiary referral centre from 1 October 2018 to 31 August 2021. Cases were stratified into abdominal and transanal cohorts. Demographics, intra-operative variables and 30-day postoperative outcomes were evaluated. Univariate analysis was performed, with statistical process control for the docking process. Main outcomes were conversion rates, morbidity, mortality and point of standardization of docking. RESULTS: In all, 133 patients were included: 93 (69.92%) abdominal and 40 (30.08%) transanal. The main diagnosis was rectal cancer (n = 59) and the procedure performed a robotic transanal abdominal transanal radical proctosigmoidectomy (n = 30). There were no conversions to open surgery. Two abdominal (2.15%) and three transanal cases (7.50%) were converted to laparoscopy. All colorectal adenocarcinomas had negative margins, proper lymph node harvest and complete mesorectal excision, as appropriate. Docking became a standardized process at cases 34 (abdominal) and 23 (anorectal). After surgery, bowel function returned on mean day 2 (abdominal) and 1 (transanal). The morbidity rate was 15.05% (abdominal) and 27.50% (transanal). There were two major morbidities in each cohort. Overall, there were three (2.65%) readmissions, one reoperation and no mortality. CONCLUSIONS: Single-port robotics is feasible for all types of colorectal procedures, with good clinical and oncological outcomes. With this development in colorectal surgery, further studies can develop best practices with this novel technology.


Asunto(s)
Neoplasias Colorrectales , Cirugía Colorrectal , Laparoscopía , Proctocolectomía Restauradora , Neoplasias del Recto , Procedimientos Quirúrgicos Robotizados , Robótica , Cirugía Endoscópica Transanal , Humanos , Neoplasias Colorrectales/cirugía , Laparoscopía/métodos , Neoplasias del Recto/cirugía , Neoplasias del Recto/patología , Procedimientos Quirúrgicos Robotizados/métodos , Cirugía Endoscópica Transanal/métodos , Estudios Prospectivos
6.
Front Cell Neurosci ; 17: 1184563, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37333893

RESUMEN

Neurons maintain their average firing rate and other properties within narrow bounds despite changing conditions. This homeostatic regulation is achieved using negative feedback to adjust ion channel expression levels. To understand how homeostatic regulation of excitability normally works and how it goes awry, one must consider the various ion channels involved as well as the other regulated properties impacted by adjusting those channels when regulating excitability. This raises issues of degeneracy and pleiotropy. Degeneracy refers to disparate solutions conveying equivalent function (e.g., different channel combinations yielding equivalent excitability). This many-to-one mapping contrasts the one-to-many mapping described by pleiotropy (e.g., one channel affecting multiple properties). Degeneracy facilitates homeostatic regulation by enabling a disturbance to be offset by compensatory changes in any one of several different channels or combinations thereof. Pleiotropy complicates homeostatic regulation because compensatory changes intended to regulate one property may inadvertently disrupt other properties. Co-regulating multiple properties by adjusting pleiotropic channels requires greater degeneracy than regulating one property in isolation and, by extension, can fail for additional reasons such as solutions for each property being incompatible with one another. Problems also arise if a perturbation is too strong and/or negative feedback is too weak, or because the set point is disturbed. Delineating feedback loops and their interactions provides valuable insight into how homeostatic regulation might fail. Insofar as different failure modes require distinct interventions to restore homeostasis, deeper understanding of homeostatic regulation and its pathological disruption may reveal more effective treatments for chronic neurological disorders like neuropathic pain and epilepsy.

7.
Process Biochem ; 129: 241-256, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37013198

RESUMEN

One of the outcomes from the global COVID-19 pandemic caused by SARS-CoV-2 has been an acceleration of development timelines to provide treatments in a timely manner. For example, it has recently been demonstrated that the development of monoclonal antibody therapeutics from vector construction to IND submission can be achieved in five to six months rather than the traditional ten-to-twelve-month timeline using CHO cells [1], [2]. This timeline is predicated on leveraging existing, robust platforms for upstream and downstream processes, analytical methods, and formulation. These platforms also reduce; the requirement for ancillary studies such as cell line stability, or long-term product stability studies. Timeline duration was further reduced by employing a transient cell line for early material supply and using a stable cell pool to manufacture toxicology study materials. The development of non-antibody biologics utilizing traditional biomanufacturing processes in CHO cells within a similar timeline presents additional challenges, such as the lack of platform processes and additional analytical assay development. In this manuscript, we describe the rapid development of a robust and reproducible process for a two-component self-assembling protein nanoparticle vaccine for SARS-CoV-2. Our work has demonstrated a successful academia-industry partnership model that responded to the COVID-19 global pandemic quickly and efficiently and could improve our preparedness for future pandemic threats.

8.
Aliment Pharmacol Ther ; 57(5): 524-539, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36314265

RESUMEN

BACKGROUND: Vedolizumab for inflammatory bowel disease (IBD) is often intensified based on distinct pharmacokinetics in children. Prior adult-specific population pharmacokinetic models have identified limited covariates of drug clearance. AIMS: To establish a population pharmacokinetic model for children and young adults to identify novel covariates of drug clearance to better account for paediatric-specific inter-patient variability in vedolizumab pharmacokinetics; a key secondary exploratory aim was to identify microbial signatures of pharmacokinetic outcomes in a subset of patients. METHODS: The study included data from 463 observed vedolizumab concentrations (59 peaks and 404 troughs) from 74 patients with IBD (52 with Crohn's disease and 22 with ulcerative colitis or unclassified IBD, median age 16 years). Pharmacokinetic analysis was conducted with non-linear mixed effects modelling. For the evaluation of the exposure-response relationship, clinical outcomes were evaluated by trough levels, clearance and vedolizumab exposure. Whole-genome metagenomic sequencing was conducted at baseline and week 2. RESULTS: A two-compartment population pharmacokinetic model was identified with a clear correlation between CL and weight, erythrocyte sedimentation rate, and hypoalbuminemia. Trough concentrations before infusion 3 (37 µg/ml) and before infusion 4 (20 µg/ml) best predicted steroid-free clinical remission at infusion 4. Using faecal metagenomics, we identified an early (baseline and week 2) abundance of butyrate-producing species and pathways that were associated with an infusion 4 trough concentration >20 µg/ml. CONCLUSIONS: This novel paediatric vedolizumab pharmacokinetic model could inform precision dosing. While additional studies are needed, an abundance of faecal butyrate producers is associated with early response to vedolizumab, suggesting that microbial analysis may be beneficial to biological selection.


Asunto(s)
Colitis Ulcerosa , Enfermedades Inflamatorias del Intestino , Humanos , Niño , Adulto Joven , Adolescente , Resultado del Tratamiento , Fármacos Gastrointestinales , Anticuerpos Monoclonales Humanizados/efectos adversos , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/inducido químicamente
9.
F S Rep ; 4(4): 337-342, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38204948

RESUMEN

Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder in women, affecting up to 15% of reproductive-aged women. Polycystic ovarian syndrome is a heterogeneous disorder, both in the sense that many different factors may play a role in its manifestation and that multiple systems throughout the body can be affected. Polycystic ovarian syndrome has been linked to an increased prevalence of various psychiatric disorders, including depression and anxiety. Despite the socioeconomic effect that these disorders may have on patients with PCOS and society as a whole, this association is largely lacking in research. There are currently several theories regarding the link between PCOS and mental health. Some suggest that the overactive hypothalamic-pituitary-ovarian and hypothalamic-pituitary-adrenal axes in PCOS patients may alter the hormonal profile and contribute to the development of psychiatric disorders. Other studies speculate that abnormal levels of neurotransmitters and neuronal signaling may play a role. Recently, more research has begun to focus on the gut-brain axis, addressing the nutritional needs of PCOS patients. Studies show that dietary factors such as probiotics and micronutrient supplementation may significantly improve psychiatric symptoms in PCOS patients while helping regulate neurotransmitter levels in the body. In this review, we examine different theories regarding the association between PCOS and psychiatric disorders and point out different areas of research that are needed to broaden our understanding of this association.

10.
Diagnostics (Basel) ; 12(7)2022 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-35885566

RESUMEN

(1) Background: Anti-carbamylated protein (CarP) antibodies have been studied as novel markers to aid in the diagnosis and prognosis of rheumatoid arthritis. (2) Methods: A total of 265 samples were included in the evaluation, for which 98 had results for anti-cyclic citrullinated peptide (CCP), 86 for rheumatoid factor (RF), and 212 for 14-3-3 eta protein. Anti-CarP antibodies were measured using a fetal calf serum-based single-step assay (research use only, Inova Diagnostics, San Diego, CA). (3) Results: Anti-CarP antibodies were significantly higher and more frequent in anti-CCP3.1+ (p = 0.0025), RF+ (p = 0.0043) and 14-3-3 eta+ (p = 0.028) samples compared to the negative counterpart group. In addition, isolated anti-CarP positivity occurred in samples negative for anti-CCP3.1, RF, or 14-3-3 eta. When anti-CarP antibodies were compared to each of the RF, anti-CCP3.1, and 14-3-3 eta by receiver operating characteristic (ROC) analyses, the area under the curve (AUC) values of 0.71 (RF), 0.68 (anti-CCP3.1), and 0.59 (14-3-3 eta), respectively, demonstrated a moderate correlation. Using an UpSet plot, we determined that 10.6% of the samples with available results for anti-CCP3.1, RF, and anti-CarP showed triple positivity. (4) Conclusions: Anti-carbamylated protein (anti-CarP) antibodies can be detected in anti-CCP, RF and 14-3-3 eta-positive and -negative patients, potentially identifying specific subsets of patients.

11.
Proc Natl Acad Sci U S A ; 119(20): e2120870119, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35544691

RESUMEN

Transient receptor potential canonical 4 (TRPC4) is a receptor-operated cation channel codependent on both the Gq/11­phospholipase C signaling pathway and Gi/o proteins for activation. This makes TRPC4 an excellent coincidence sensor of neurotransmission through Gq/11- and Gi/o-coupled receptors. In whole-cell slice recordings of lateral septal neurons, TRPC4 mediates a strong depolarizing plateau that shuts down action potential firing, which may or may not be followed by a hyperpolarization that extends the firing pause to varying durations depending on the strength of Gi/o stimulation. We show that the depolarizing plateau is codependent on Gq/11-coupled group I metabotropic glutamate receptors and on Gi/o-coupled γ-aminobutyric acid type B receptors. The hyperpolarization is mediated by Gi/o activation of G protein­activated inwardly rectifying K+ (GIRK) channels. Moreover, the firing patterns, elicited by either electrical stimulation or receptor agonists, encode information about the relative strengths of Gq/11 and Gi/o inputs in the following fashion. Pure Gq/11 input produces weak depolarization accompanied by firing acceleration, whereas pure Gi/o input causes hyperpolarization that pauses firing. Although coincident Gq/11­Gi/o inputs also pause firing, the pause is preceded by a burst, and both the pause duration and firing recovery patterns reflect the relative strengths of Gq/11 versus Gi/o inputs. Computer simulations demonstrate that different combinations of TRPC4 and GIRK conductances are sufficient to produce the range of firing patterns observed experimentally. Thus, concurrent neurotransmission through the Gq/11 and Gi/o pathways is converted to discernible electrical responses by the joint actions of TRPC4 and GIRK for communication to downstream neurons.


Asunto(s)
Potenciales de Acción , Canales de Potasio Rectificados Internamente Asociados a la Proteína G , Subunidades alfa de la Proteína de Unión al GTP Gi-Go , Subunidades alfa de la Proteína de Unión al GTP , Neuronas , Transmisión Sináptica , Canales Catiónicos TRPC , Animales , Comunicación Celular , Canales de Potasio Rectificados Internamente Asociados a la Proteína G/fisiología , Subunidades alfa de la Proteína de Unión al GTP/fisiología , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/fisiología , Ratones , Neuronas/fisiología , Canales Catiónicos TRPC/fisiología
12.
BMJ Open ; 12(5): e052407, 2022 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-35545397

RESUMEN

BACKGROUND: Pandemics often precipitate declines in essential health service utilisation, which can ultimately kill more people than the disease outbreak itself. There is some evidence, however, that the presence of adequately supported community health workers (CHWs), that is, financially remunerated, trained, supplied and supervised in line with WHO guidelines, may blunt the impact of health system shocks. Yet, adequate support for CHWs is often missing or uneven across countries. This study assesses whether adequately supported CHWs can maintain the continuity of essential community-based health service provision during the COVID-19 pandemic. METHODS: Interrupted time series analysis. Monthly routine data from 27 districts across four countries in sub-Saharan Africa were extracted from CHW and facility reports for the period January 2018-June 2021. Descriptive analysis, null hypothesis testing, and segmented regression analysis were used to assess the presence and magnitude of a possible disruption in care utilisation after the earliest reported cases of COVID-19. RESULTS: CHWs across all sites were supported in line with the WHO Guideline and received COVID-19 adapted protocols, training and personal protective equipment within 45 days after the first case in each country. We found no disruptions to the coverage of proactive household visits or integrated community case management (iCCM) assessments provided by these prepared and protected CHWs, as well as no disruptions to the speed with which iCCM was received, pregnancies were registered or postnatal care received. CONCLUSION: CHWs who were equipped and prepared for the pandemic were able to maintain speed and coverage of community-delivered care during the pandemic period. Given that the majority of CHWs globally remain unpaid and largely unsupported, this paper suggests that the opportunity cost of not professionalising CHWs may be larger than previously estimated, particularly in light of the inevitability of future pandemics.


Asunto(s)
COVID-19 , COVID-19/epidemiología , Servicios de Salud Comunitaria , Agentes Comunitarios de Salud/educación , Atención a la Salud , Humanos , Análisis de Series de Tiempo Interrumpido , Pandemias
13.
Front Neurosci ; 16: 836412, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35392415

RESUMEN

Stroke is an acute cerebrovascular disease with high incidence, high mortality, and high disability rate. Determining the location and volume of the disease in MR images promotes accurate stroke diagnosis and surgical planning. Therefore, the automatic recognition and segmentation of stroke lesions has important clinical significance for large-scale stroke imaging analysis. There are some problems in the segmentation of stroke lesions, such as imbalance of the front and back scenes, uncertainty of position, and unclear boundary. To meet this challenge, this paper proposes a cross-attention and deep supervision UNet (CADS-UNet) to segment chronic stroke lesions from T1-weighted MR images. Specifically, we propose a cross-spatial attention module, which is different from the usual self-attention module. The location information interactively selects encode features and decode features to enrich the lost spatial focus. At the same time, the channel attention mechanism is used to screen the channel characteristics. Finally, combined with deep supervision and mixed loss, the model is supervised more accurately. We compared and verified the model on the authoritative open dataset "Anatomical Tracings of Lesions After Stroke" (Atlas), which fully proved the effectiveness of our model.

14.
iScience ; 25(4): 104000, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35313693

RESUMEN

The gut microbiota can affect how animals respond to ingested toxins, such as ethanol, which is prevalent in the diets of diverse animals and often leads to negative health outcomes in humans. Ethanol is a complex dietary factor because it acts as a toxin, behavioral manipulator, and nutritional source, with both direct effects on the host as well as indirect ones through the microbiome. Here, we developed a model for chronic, non-intoxicating ethanol ingestion in the adult fruit fly, Drosophila melanogaster, and paired this with the tractability of the fly gut microbiota, which can be experimentally removed. We linked numerous physiological, behavioral, and transcriptional variables to fly fitness, including a combination of intestinal barrier integrity, stored triglyceride levels, feeding behavior, and the immunodeficiency pathway. Our results reveal a complex tradeoff between lifespan and fecundity that is microbiome-dependent and modulated by dietary ethanol and feeding behavior.

15.
Elife ; 112022 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-35293858

RESUMEN

Neurons regulate their excitability by adjusting their ion channel levels. Degeneracy - achieving equivalent outcomes (excitability) using different solutions (channel combinations) - facilitates this regulation by enabling a disruptive change in one channel to be offset by compensatory changes in other channels. But neurons must coregulate many properties. Pleiotropy - the impact of one channel on more than one property - complicates regulation because a compensatory ion channel change that restores one property to its target value often disrupts other properties. How then does a neuron simultaneously regulate multiple properties? Here, we demonstrate that of the many channel combinations producing the target value for one property (the single-output solution set), few combinations produce the target value for other properties. Combinations producing the target value for two or more properties (the multioutput solution set) correspond to the intersection between single-output solution sets. Properties can be effectively coregulated only if the number of adjustable channels (nin) exceeds the number of regulated properties (nout). Ion channel correlations emerge during homeostatic regulation when the dimensionality of solution space (nin - nout) is low. Even if each property can be regulated to its target value when considered in isolation, regulation as a whole fails if single-output solution sets do not intersect. Our results also highlight that ion channels must be coadjusted with different ratios to regulate different properties, which suggests that each error signal drives modulatory changes independently, despite those changes ultimately affecting the same ion channels.


Asunto(s)
Canales Iónicos , Neuronas , Homeostasis , Canales Iónicos/fisiología , Neuronas/fisiología
16.
Aliment Pharmacol Ther ; 55(5): 593-603, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34935161

RESUMEN

BACKGROUND: Antibodies to infliximab (ATI) are associated with secondary loss of response and increased risk for drug reactions. Limited studies have associated ATI with increased infliximab clearance. AIMS: We assessed the impact of ATI on infliximab clearance and loss of response in an inception paediatric Crohn's disease cohort with 1-year follow-up. METHODS: This multi-centre prospective cohort study collected peak and trough serum infliximab/ATI concentrations from 660 infusions (78 patients) during the first year of therapy. Clinicians were blinded to these research labs. The primary outcome was the difference in infliximab clearance between ATI-positive (ATI) and ATI-negative (no-ATI) patients. Secondary outcomes included pre-treatment predictors of ATI (including HLA-DQA1 genotyping). Clinical remission, loss of response and infliximab clearance were compared between pre-ATI, during ATI and following ATI resolution with MANOVA. Time to ATI was calculated by Cox proportional Hazards model. RESULTS: ATI were detected in 68% (53/78) patients with a median concentration of 76 ng/mL (range 23-1828). Maximum ATI concentration was <200 ng/mL in 73.6% (39/53). Median clearance in ATI patients was higher (with higher clearance if loss of response), compared to no-ATI patients (P < 0.001). Neutrophil CD64 ratio >6 and starting dose <7.5 mg/kg independently predicted ATI in multivariable regression, while HLA-DQA1*05 presence did not. Dose adjustment resolved ATI in 37.5% (12/32) patients with concomitant infliximab concentration and clearance recovery. A maximum ATI level of ≤99 ng/mL predicted ATI resolution (area under the receiver operating curve 0.80 [95% CI 0.64-0.96]). CONCLUSIONS: In this real-world cohort, ATI as low as 23 ng/mL impacted drug clearance. Our data suggest that dose optimisation for low-level ATI can improve infliximab clearance and prevent loss of response.


Asunto(s)
Enfermedad de Crohn , Anticuerpos , Niño , Fármacos Gastrointestinales/uso terapéutico , Humanos , Infliximab , Estudios Prospectivos
17.
Front Neurosci ; 15: 782968, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34899175

RESUMEN

As a non-invasive, low-cost medical imaging technology, magnetic resonance imaging (MRI) has become an important tool for brain tumor diagnosis. Many scholars have carried out some related researches on MRI brain tumor segmentation based on deep convolutional neural networks, and have achieved good performance. However, due to the large spatial and structural variability of brain tumors and low image contrast, the segmentation of MRI brain tumors is challenging. Deep convolutional neural networks often lead to the loss of low-level details as the network structure deepens, and they cannot effectively utilize the multi-scale feature information. Therefore, a deep convolutional neural network with a multi-scale attention feature fusion module (MAFF-ResUNet) is proposed to address them. The MAFF-ResUNet consists of a U-Net with residual connections and a MAFF module. The combination of residual connections and skip connections fully retain low-level detailed information and improve the global feature extraction capability of the encoding block. Besides, the MAFF module selectively extracts useful information from the multi-scale hybrid feature map based on the attention mechanism to optimize the features of each layer and makes full use of the complementary feature information of different scales. The experimental results on the BraTs 2019 MRI dataset show that the MAFF-ResUNet can learn the edge structure of brain tumors better and achieve high accuracy.

18.
BMJ Glob Health ; 6(11)2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34815242

RESUMEN

BACKGROUND: Proactive community case management (ProCCM) has shown promise to advance goals of universal health coverage (UHC). ProCCM community health workers (CHWs) face operational challenges when pursuing their goal of visiting every household in their service area at least twice monthly to proactively find sick patients. We developed a software extension (UHC Mode) to an existing CHW mobile application featuring user interface design improvements to support CHWs in planning daily home visits. We evaluated the effect of UHC Mode on minimum expected home visit coverage. METHODS: We conducted a parallel-group, two-arm randomised controlled trial of ProCCM CHWs in two separate regions in Mali. CHWs were randomly assigned to UHC Mode or the standard mobile application (control) with a 1:1 allocation. Randomisation was stratified by health catchment area. CHWs and other programme personnel were not masked to arm allocation. CHWs used their assigned intervention for 4 months. Using a difference-in-differences analysis, we estimated the mean change in minimum expected home visit coverage from preintervention to postintervention between arms. RESULTS: Enrolment occurred in January 2019. Of 199 eligible CHWs randomised to the intervention or control arm, 196 were enrolled and 195 were included in the analysis. Households whose CHW used UHC Mode had 2.41 times higher odds of minimum expected home visit coverage compared with households whose CHW used the control (95% CI 1.68 to 3.47; p<0.0005). Minimum expected home visit coverage in the UHC Mode arm increased 13.6 percentage points (95% CI 8.1 to 19.0) compared with the control arm. CONCLUSION: Our findings suggest UHC Mode is an effective tool that can improve home visit coverage and promote progress towards UHC when implemented in the ProCCM context. User interface design of health information systems that supports health workers' daily practices and meets their requirements can have a positive impact on health worker performance and home visit coverage. TRIAL REGISTRATION NUMBER: NCT04106921.


Asunto(s)
Visita Domiciliaria , Aplicaciones Móviles , Agentes Comunitarios de Salud , Humanos , Malí
19.
Clin Chem ; 67(12): 1618-1627, 2021 11 26.
Artículo en Inglés | MEDLINE | ID: mdl-34718463

RESUMEN

BACKGROUND: Chromogranin A (CgA) is a 48 kDa protein that serves as a diagnostically sensitive, but nonspecific, serum biomarker for neuroendocrine tumors. Immunoassays for CgA are not standardized and have a narrow dynamic range, which requires dilution of concentrated specimens. We developed and validated an antibody-free, liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based method for CgA without these limitations. METHODS: CgA was extracted from serum using a mixed-mode anion exchange solid-phase extraction plate, digested with trypsin, and analyzed by LC-MS/MS using well-characterized CgA calibration standards. After validation, the mass spectrometry method was compared with the CISBIO immunoassay using 200 serum specimens previously submitted for CgA analysis. Specimens with discordant results were reanalyzed by high-resolution mass spectrometry- (HRMS) -based methods to assess the contribution of truncated and post-translationally modified forms of CgA. RESULTS: The assay had a linear range of 50 to 50 000 ng/mL, recoveries between 89% and 115%, and intra- and interassay imprecision <10%. LC-MS/MS assay results showed a Pearson's correlation of r = 0.953 with the CISBIO immunoassay, with CgA values being a mean 2- to 4-fold higher. Concordance for CgA between the 2 assays was 80.9% (95% CI 72.8%-89.2%), showing substantial agreement. Truncation and posttranslational modification, including 2 phosphorylation sites that had not been previously observed or predicted to our knowledge, did not appear to contribute directly to discordance between the 2 assays. CONCLUSION: Quantification of CgA by LC-MS/MS provides an analytically sensitive and reproducible alternative to commercially available immunoassays.


Asunto(s)
Cromogranina A , Tumores Neuroendocrinos , Espectrometría de Masas en Tándem , Cromatografía Liquida , Cromogranina A/sangre , Humanos , Inmunoensayo , Tumores Neuroendocrinos/diagnóstico , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodos
20.
ACS Appl Mater Interfaces ; 13(44): 51809-51828, 2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34310110

RESUMEN

Professor Chia-Kuang (Frank) Tsung made his scientific impact primarily through the atomic-level design of nanoscale materials for application in heterogeneous catalysis. He approached this challenge from two directions: above and below the material surface. Below the surface, Prof. Tsung synthesized finely controlled nanoparticles, primarily of noble metals and metal oxides, tailoring their composition and surface structure for efficient catalysis. Above the surface, he was among the first to leverage the tunability and stability of metal-organic frameworks (MOFs) to improve heterogeneous, molecular, and biocatalysts. This article, written by his former students, seeks first to commemorate Prof. Tsung's scientific accomplishments in three parts: (1) rationally designing nanocrystal surfaces to promote catalytic activity; (2) encapsulating nanocrystals in MOFs to improve catalyst selectivity; and (3) tuning the host-guest interaction between MOFs and guest molecules to inhibit catalyst degradation. The subsequent discussion focuses on building on the foundation laid by Prof. Tsung and on his considerable influence on his former group members and collaborators, both inside and outside of the lab.

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