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1.
Nature ; 631(8022): 755-759, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39048682

RESUMEN

Stable diffusion revolutionized image creation from descriptive text. GPT-2 (ref. 1), GPT-3(.5) (ref. 2) and GPT-4 (ref. 3) demonstrated high performance across a variety of language tasks. ChatGPT introduced such language models to the public. It is now clear that generative artificial intelligence (AI) such as large language models (LLMs) is here to stay and will substantially change the ecosystem of online text and images. Here we consider what may happen to GPT-{n} once LLMs contribute much of the text found online. We find that indiscriminate use of model-generated content in training causes irreversible defects in the resulting models, in which tails of the original content distribution disappear. We refer to this effect as 'model collapse' and show that it can occur in LLMs as well as in variational autoencoders (VAEs) and Gaussian mixture models (GMMs). We build theoretical intuition behind the phenomenon and portray its ubiquity among all learned generative models. We demonstrate that it must be taken seriously if we are to sustain the benefits of training from large-scale data scraped from the web. Indeed, the value of data collected about genuine human interactions with systems will be increasingly valuable in the presence of LLM-generated content in data crawled from the Internet.

2.
J Neuroendocrinol ; : e13418, 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38852954

RESUMEN

G protein-coupled receptors (GPCRs) are central to the functioning of the hypothalamic-pituitary-gonadal axis (HPG axis) and include the rhodopsin-like GPCR family members, neurokinin 3 receptor, kappa-opioid receptor, kisspeptin 1 receptor, gonadotropin-releasing hormone receptor, and the gonadotropin receptors, luteinizing hormone/choriogonadotropin receptor and follicle-stimulating hormone receptor. Unsurprisingly, inactivating variants of these receptors have been implicated in a spectrum of reproductive phenotypes, including failure to undergo puberty, and infertility. Clinical induction of puberty in patients harbouring such variants is possible, but restoration of fertility is not always a realisable outcome, particularly for those patients suffering from primary hypogonadism. Thus, novel pharmaceuticals and/or a fundamental change in approach to treating these patients are required. The increasing wealth of data describing the effects of coding-region genetic variants on GPCR function has highlighted that the majority appear to be dysfunctional as a result of misfolding of the encoded receptor protein, which, in turn, results in impaired receptor trafficking through the secretory pathway to the cell surface. As such, these intracellularly retained receptors may be amenable to 'rescue' using a pharmacological chaperone (PC)-based approach. PCs are small, cell permeant molecules hypothesised to interact with misfolded intracellularly retained proteins, stabilising their folding and promoting their trafficking through the secretory pathway. In support of the use of this approach as a viable therapeutic option, it has been observed that many rescued variant GPCRs retain at least a degree of functionality when 'rescued' to the cell surface. In this review, we examine the GPCR PC research landscape, focussing on the rescue of inactivating variant GPCRs with important roles in the HPG axis, and describe what is known regarding the mechanisms by which PCs restore trafficking and function. We also discuss some of the merits and obstacles associated with taking this approach forward into a clinical setting.

3.
J Nonverbal Behav ; 48(1): 137-159, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38566623

RESUMEN

A significant body of research has investigated potential correlates of deception and bodily behavior. The vast majority of these studies consider discrete, subjectively coded bodily movements such as specific hand or head gestures. Such studies fail to consider quantitative aspects of body movement such as the precise movement direction, magnitude and timing. In this paper, we employ an innovative data mining approach to systematically study bodily correlates of deception. We re-analyze motion capture data from a previously published deception study, and experiment with different data coding options. We report how deception detection rates are affected by variables such as body part, the coding of the pose and movement, the length of the observation, and the amount of measurement noise. Our results demonstrate the feasibility of a data mining approach, with detection rates above 65%, significantly outperforming human judgement (52.80%). Owing to the systematic analysis, our analyses allow for an understanding of the importance of various coding factor. Moreover, we can reconcile seemingly discrepant findings in previous research. Our approach highlights the merits of data-driven research to support the validation and development of deception theory.

4.
Proc Biol Sci ; 291(2019): 20232606, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38503334

RESUMEN

The brain is thought to be among the first human organs to decompose after death. The discovery of brains preserved in the archaeological record is therefore regarded as unusual. Although mechanisms such as dehydration, freezing, saponification, and tanning are known to allow for the preservation of the brain on short time scales in association with other soft tissues (≲4000 years), discoveries of older brains, especially in the absence of other soft tissues, are rare. Here, we collated an archive of more than 4400 human brains preserved in the archaeological record across approximately 12 000 years, more than 1300 of which constitute the only soft tissue preserved amongst otherwise skeletonized remains. We found that brains of this type persist on time scales exceeding those preserved by other means, which suggests an unknown mechanism may be responsible for preservation particular to the central nervous system. The untapped archive of preserved ancient brains represents an opportunity for bioarchaeological studies of human evolution, health and disease.


Asunto(s)
Encéfalo , Sistema Nervioso Central , Humanos , Cabeza
5.
Sci Total Environ ; 917: 170301, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38272094

RESUMEN

The fragmentation of plastic debris is a key pathway to the formation of microplastic pollution. These disintegration processes depend on the materials' physical and chemical characteristics, but insight into these interrelationships is still limited, especially under natural conditions. Five plastics of known polymer/additive compositions and processing histories were deployed in aquatic environments and recovered after six and twelve months. The polymer types used were linear low density polyethylene (LLDPE), oxo-degradable LLDPE (oxoLLDPE), poly(ethylene terephthalate) (PET), polyamide-6 (PA6), and poly(lactic acid) (PLA). Four geographically distinct locations across Aotearoa/New Zealand were chosen: three marine sites and a wastewater treatment plant (WWTP). Accelerated UV-weathering under controlled laboratory conditions was also carried out to evaluate artificial ageing as a model for plastic degradation in the natural environment. The samples' physical characteristics and surface microstructures were studied for each deployment location and exposure time. The strongest effects were found for oxoLLDPE upon artificial ageing, with increased crystallinity, intense surface cracking, and substantial deterioration of its mechanical properties. However, no changes to the same extent were found after recovery of the deployed material. In the deployment environments, the chemical nature of the plastics was the most relevant factor determining their behaviours. Few significant differences between the four aquatic locations were identified, except for PA6, where indications for biological surface degradation were found only in seawater, not the WWTP. In some cases, artificial ageing reasonably mimicked the changes which some plastic properties underwent in aquatic environments, but generally, it was no reliable model for natural degradation processes. The findings from this study have implications for the understanding of the initial phases of plastic degradation in aquatic environments, eventually leading to microplastics formation. They can also guide the interpretation of accelerated laboratory ageing for the fate of aquatic plastic pollution, and for the testing of aged plastic samples.

6.
Antib Ther ; 6(4): 277-297, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38075238

RESUMEN

Background: Due to COVID-19, pandemic preparedness emerges as a key imperative, necessitating new approaches to accelerate development of reagents against infectious pathogens. Methods: Here, we developed an integrated approach combining synthetic, computational and structural methods with in vitro antibody selection and in vivo immunization to design, produce and validate nature-inspired nanoparticle-based reagents against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Results: Our approach resulted in two innovations: (i) a thermostable nasal vaccine called ADDoCoV, displaying multiple copies of a SARS-CoV-2 receptor binding motif derived epitope and (ii) a multivalent nanoparticle superbinder, called Gigabody, against SARS-CoV-2 including immune-evasive variants of concern (VOCs). In vitro generated neutralizing nanobodies and electron cryo-microscopy established authenticity and accessibility of epitopes displayed by ADDoCoV. Gigabody comprising multimerized nanobodies prevented SARS-CoV-2 virion attachment with picomolar EC50. Vaccinating mice resulted in antibodies cross-reacting with VOCs including Delta and Omicron. Conclusion: Our study elucidates Adenovirus-derived dodecamer (ADDomer)-based nanoparticles for use in active and passive immunization and provides a blueprint for crafting reagents to combat respiratory viral infections.

7.
Trends Ecol Evol ; 38(11): 1060-1071, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37385847

RESUMEN

Estimates for animal antiquity exhibit a significant disconnect between those from molecular clocks, which indicate crown animals evolved ∼800 million years ago (Ma), and those from the fossil record, which extends only ∼574 Ma. Taphonomy is often held culpable: early animals were too small/soft/fragile to fossilise, or the circumstances that preserve them were uncommon in the early Neoproterozoic. We assess this idea by comparing Neoproterozoic fossilisation processes with those of the Cambrian and its abundant animal fossils. Cambrian Burgess Shale-type (BST) preservation captures animals in mudstones showing a narrow range of mineralogies; yet, fossiliferous Neoproterozoic mudstones rarely share the same mineralogy. Animal fossils are absent where BST preservation occurs in deposits ≥789 Ma, suggesting a soft maximum constraint on animal antiquity.


Asunto(s)
Evolución Biológica , Fósiles , Animales , Proteínas CLOCK
8.
Phys Chem Chem Phys ; 25(8): 6009-6015, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36752555

RESUMEN

We present an initial demonstration of a velocity-map imaging (VMI) experiment using a back-irradiation laser-based desorption source directly integrated into the electrode assembly. This has the potential to greatly expand the utility of the popular VMI approach by permitting its use with high density plumes of non-volatile molecular samples. Photoelectron circular dichroism measurements on the phenylalanine molecule using 400 nm multiphoton ionization are used to illustrate this novel method, revealing forward-backward emission asymmetries on the order of 7%.

9.
Int J Mol Sci ; 24(3)2023 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-36768456

RESUMEN

Radiopharmaceutical development hinges on the affinity and selectivity of the biological component for the intended target. An analogue of the neuropeptide Substance P (SP), 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-[Thi8,Met(O2)11]-SP (DOTA-[Thi8,Met(O2)11]SP), in the theranostic pair [68Ga]Ga-/ [213Bi]Bi-DOTA-[Thi8,Met(O2)11]SP has shown promising clinical results in the treatment of inoperable glioblastoma. As the theranostic targeting component, modifications to SP that affect the selectivity of the resulting analogue for the intended target (neurokinin-1 receptor [NK1R]) could be detrimental to its therapeutic potential. In addition to other closely related tachykinin receptors (neurokinin-2 receptor [NK2R] and neurokinin-3 receptor [NK3R]), SP can activate a mast cell expressed receptor Mas-related G protein-coupled receptor subtype 2 (MRGPRX2), which has been implicated in allergic-type reactions. Therefore, activation of these receptors by SP analogues has severe implications for their therapeutic potential. Here, the receptor selectivity of DOTA-[Thi8,Met(O2)11]SP was examined using inositol phosphate accumulation assay in HEK293-T cells expressing NK1R, NK2R, NK3R or MRGPRX2. DOTA-[Thi8,Met(O2)11]SP had similar efficacy and potency as native SP at NK1R, but displayed greater NK1R selectivity. DOTA-[Thi8,Met(O2)11]SP was unable to elicit significant activation of the other tachykinin receptors nor MRGPRX2 at high concentrations nor did it display antagonistic behaviour at these receptors. DOTA-[Thi8,Met(O2)11]SP, therefore has high potency and selectivity for NK1R, supporting its potential for targeted theranostic use in glioblastoma multiforme and other conditions characterised by NK1R overexpression.


Asunto(s)
Glioblastoma , Sustancia P , Humanos , Receptores de Taquicininas , Células HEK293 , Receptores de Neuroquinina-1 , Receptores de Neuroquinina-2 , Proteínas del Tejido Nervioso , Receptores de Neuropéptido , Receptores Acoplados a Proteínas G
10.
Ann Neurol ; 93(5): 1029-1039, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36641645

RESUMEN

OBJECTIVE: Bradykinesia is the major cardinal motor sign of Parkinson disease (PD), but its neural underpinnings are unclear. The goal of this study was to examine whether changes in bradykinesia following long-term subthalamic nucleus (STN) deep brain stimulation (DBS) are linked to local STN beta (13-30 Hz) dynamics or a wider bilateral network dysfunction. METHODS: Twenty-one individuals with PD implanted with sensing neurostimulators (Activa® PC + S, Medtronic, PLC) in the STN participated in a longitudinal 'washout' therapy study every three to 6 months for an average of 3 years. At each visit, participants were withdrawn from medication (12/24/48 hours) and had DBS turned off (>60 minutes) before completing a repetitive wrist-flexion extension task, a validated quantitative assessment of bradykinesia, while local field potentials were recorded. Local STN beta dynamics were investigated via beta power and burst duration, while interhemispheric beta synchrony was assessed with STN-STN beta coherence. RESULTS: Higher interhemispheric STN beta coherence, but not contralateral beta power or burst duration, was significantly associated with worse bradykinesia. Bradykinesia worsened off therapy over time. Interhemispheric STN-STN beta coherence also increased over time, whereas beta power and burst duration remained stable. The observed change in bradykinesia was related to the change in interhemispheric beta coherence, with greater increases in synchrony associated with further worsening of bradykinesia. INTERPRETATION: Together, these findings implicate interhemispheric beta synchrony as a neural correlate of the progression of bradykinesia following chronic STN DBS. This could imply the existence of a pathological bilateral network contributing to bradykinesia in PD. ANN NEUROL 2023;93:1029-1039.


Asunto(s)
Estimulación Encefálica Profunda , Enfermedad de Parkinson , Núcleo Subtalámico , Humanos , Hipocinesia/complicaciones , Estimulación Encefálica Profunda/efectos adversos , Enfermedad de Parkinson/terapia , Enfermedad de Parkinson/tratamiento farmacológico , Núcleo Subtalámico/fisiología
11.
Cureus ; 14(8): e28387, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36176855

RESUMEN

Frame-based stereotactic localization is an important step for targeting during a surgical procedure. The motion may cause artifacts in this step reducing the accuracy of surgical targeting. While modeling of motion in real-life scenarios may be difficult, herein we analyzed the case where motion was suspected to impact the localization step. In this case, a scan with and without motion was performed with a 3N localizer, allowing for a thorough analysis. Pseudo-bending of straight rods was seen when analyzing the data. This pseudo-bending appears to occur because head-frame motion during imaging acquisition decreases the accuracy of the subsequent reconstruction, which depends on Digital Imaging and Communications in Medicine (DICOM) metadata to specify the slice-to-slice location that assumes embedded object stability. Comparison of single-slice and multi-slice stereotactic localization allowed for comparative errors for each slice in a volume. This comparative error demonstrated low error when the patient was under general anesthesia and presumed not to have moved, whereas a higher error was present during the scan with motion. Pseudo-bending can be corrected by using only localizer fiducial-based information to reorient the pixels in the volume, thus creating a reoriented localizer scan. Finally, targeting demonstrated a low error of 0.1 mm (+/- 0.1 mm) using this reoriented localizer scan, signifying that this method could be used to improve or recover from motion problems. Finally, it is concluded that stability and elimination of motion for all images utilized for stereotactic surgery are critical to ensure the best possible accuracy for the procedure.

12.
Proc Natl Acad Sci U S A ; 119(27): e2113749119, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35763574

RESUMEN

Kisspeptin neurons in the mediobasal hypothalamus (MBH) are critical targets of ovarian estrogen feedback regulating mammalian fertility. To reveal molecular mechanisms underlying this signaling, we thoroughly characterized the estrogen-regulated transcriptome of kisspeptin cells from ovariectomized transgenic mice substituted with 17ß-estradiol or vehicle. MBH kisspeptin neurons were harvested using laser-capture microdissection, pooled, and subjected to RNA sequencing. Estrogen treatment significantly (p.adj. < 0.05) up-regulated 1,190 and down-regulated 1,139 transcripts, including transcription factors, neuropeptides, ribosomal and mitochondrial proteins, ion channels, transporters, receptors, and regulatory RNAs. Reduced expression of the excitatory serotonin receptor-4 transcript (Htr4) diminished kisspeptin neuron responsiveness to serotonergic stimulation. Many estrogen-regulated transcripts have been implicated in puberty/fertility disorders. Patients (n = 337) with congenital hypogonadotropic hypogonadism (CHH) showed enrichment of rare variants in putative CHH-candidate genes (e.g., LRP1B, CACNA1G, FNDC3A). Comprehensive characterization of the estrogen-dependent kisspeptin neuron transcriptome sheds light on the molecular mechanisms of ovary-brain communication and informs genetic research on human fertility disorders.


Asunto(s)
Núcleo Arqueado del Hipotálamo , Estrógenos , Fertilidad , Kisspeptinas , Neuronas , Ovario , Animales , Núcleo Arqueado del Hipotálamo/metabolismo , Estrógenos/metabolismo , Femenino , Fertilidad/genética , Perfilación de la Expresión Génica , Humanos , Hipogonadismo/congénito , Hipogonadismo/genética , Kisspeptinas/genética , Kisspeptinas/metabolismo , Ratones , Ratones Transgénicos , Neuronas/metabolismo , Ovario/metabolismo
13.
Int J Mol Sci ; 23(9)2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35562976

RESUMEN

G protein-coupled receptors (GPCRs) facilitate the majority of signal transductions across cell membranes in humans, with numerous diseases attributed to inactivating GPCR mutations. Many of these mutations result in misfolding during nascent receptor synthesis in the endoplasmic reticulum (ER), resulting in intracellular retention and degradation. Pharmacological chaperones (PCs) are cell-permeant small molecules that can interact with misfolded receptors in the ER and stabilise/rescue their folding to promote ER exit and trafficking to the cell membrane. The neurokinin 3 receptor (NK3R) plays a pivotal role in the hypothalamic-pituitary-gonadal reproductive axis. We sought to determine whether NK3R missense mutations result in a loss of cell surface receptor expression and, if so, whether a cell-permeant small molecule NK3R antagonist could be repurposed as a PC to restore function to these mutants. Quantitation of cell surface expression levels of seven mutant NK3Rs identified in hypogonadal patients indicated that five had severely impaired cell surface expression. A small molecule NK3R antagonist, M8, increased cell surface expression in four of these five and resulted in post-translational receptor processing in a manner analogous to the wild type. Importantly, there was a significant improvement in receptor activation in response to neurokinin B (NKB) for all four receptors following their rescue with M8. This demonstrates that M8 may have potential for therapeutic development in the treatment of hypogonadal patients harbouring NK3R mutations. The repurposing of existing small molecule GPCR modulators as PCs represents a novel and therapeutically viable option for the treatment of disorders attributed to mutations in GPCRs that cause intracellular retention.


Asunto(s)
Neuroquinina B , Receptores de Neuroquinina-3 , Membrana Celular/metabolismo , Humanos , Mutación , Neuroquinina B/genética , Neuroquinina B/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Neuroquinina-3/antagonistas & inhibidores , Receptores de Neuroquinina-3/genética , Receptores de Neuroquinina-3/metabolismo
14.
Front Neurosci ; 15: 733203, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34858125

RESUMEN

Background: Resting state beta band (13-30 Hz) oscillations represent pathological neural activity in Parkinson's disease (PD). It is unknown how the peak frequency or dynamics of beta oscillations may change among fine, limb, and axial movements and different disease phenotypes. This will be critical for the development of personalized closed loop deep brain stimulation (DBS) algorithms during different activity states. Methods: Subthalamic (STN) and local field potentials (LFPs) were recorded from a sensing neurostimulator (Activa® PC + S, Medtronic PLC.) in fourteen PD participants (six tremor-dominant and eight akinetic-rigid) off medication/off STN DBS during 30 s of repetitive alternating finger tapping, wrist-flexion extension, stepping in place, and free walking. Beta power peaks and beta burst dynamics were identified by custom algorithms and were compared among movement tasks and between tremor-dominant and akinetic-rigid groups. Results: Beta power peaks were evident during fine, limb, and axial movements in 98% of movement trials; the peak frequencies were similar during each type of movement. Burst power and duration were significantly larger in the high beta band, but not in the low beta band, in the akinetic-rigid group compared to the tremor-dominant group. Conclusion: The conservation of beta peak frequency during different activity states supports the feasibility of patient-specific closed loop DBS algorithms driven by the dynamics of the same beta band during different activities. Akinetic-rigid participants had greater power and longer burst durations in the high beta band than tremor-dominant participants during movement, which may relate to the difference in underlying pathophysiology between phenotypes.

15.
Ann Clin Transl Neurol ; 8(11): 2110-2120, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34636182

RESUMEN

OBJECTIVE: To investigate the progression of neural and motor features of Parkinson's disease in a longitudinal study, after washout of medication and bilateral subthalamic nucleus deep brain stimulation (STN DBS). METHODS: Participants with clinically established Parkinson's disease underwent bilateral implantation of DBS leads (18 participants, 13 male) within the STN using standard functional frameless stereotactic technique and multi-pass microelectrode recording. Both DBS leads were connected to an implanted investigative sensing neurostimulator (Activa™ PC + S, Medtronic, PLC). Resting state STN local field potentials (LFPs) were recorded and motor disability, (the Movement Disorder Society-Unified Parkinson's Disease Rating Scale - motor subscale, MDS-UPDRS III) was assessed off therapy at initial programming, and after 6 months, 1 year, and yearly out to 5 years of treatment. The primary endpoint was measured at 3 years. At each visit, medication had been held for over 12/24 h and DBS was turned off for at least 60 min, by which time LFP spectra reached a steady state. RESULTS: After 3 years of chronic DBS, there were no increases in STN beta band dynamics (p = 0.98) but there were increases in alpha band dynamics (p = 0.0027, 25 STNs). Similar results were observed in a smaller cohort out to 5 years. There was no increase in the MDS-UPDRS III score. INTERPRETATION: These findings provide evidence that the beta oscillopathy does not substantially progress following combined STN DBS plus medication in moderate to advanced Parkinson's disease.


Asunto(s)
Ritmo beta/fisiología , Estimulación Encefálica Profunda , Progresión de la Enfermedad , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/terapia , Núcleo Subtalámico/fisiopatología , Adulto , Anciano , Ritmo alfa/fisiología , Estudios de Seguimiento , Humanos , Neuroestimuladores Implantables , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud
16.
Transl Androl Urol ; 10(5): 2043-2050, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34159085

RESUMEN

BACKGROUND: To evaluate erectile and sexual function after pelvic fracture urethral injury (PFUI) by performing a retrospective review of a large multi-center database. We hypothesized that most men will have erectile dysfunction (ED) and poor sexual function following PFUI, which will remain after posterior urethroplasty. METHODS: Using the Trauma and Urologic Reconstructive Networks of Surgeons (TURNS) database, we identified PFUI patients undergoing posterior urethroplasty. We excluded patients with incomplete demographic, surgical and/or questionnaire data. Sexual Health Inventory of Men (SHIM), Male Sexual Health Questionnaire (MSHQ), and subjective changes in penile curvature were collected before urethroplasty surgery and at follow-up. We performed descriptive statistics for erectile and ejaculatory function using STATA v12. RESULTS: We identified 92 men meeting inclusion criteria; median age was 41.7 years and BMI was 26.5. The mechanism of injury was blunt in all patients, and average distraction defect length was 2.3 cm (SD 1.0 cm). In the 38 patients who completed both pre and post-operative SHIM questionnaires, the mean SHIM score was 10.5 (SD 7.0), with 63% having severe ED (SHIM <12). The median follow-up was 5.6 months and the mean post-operative SHIM was 9.3 (SD 6.5), with 68% having severe ED. The mean change in SHIM score was -1.18 (SD 6.29) with 6 (16%) patients reporting de novo ED (≥5 point decrease in score). Of the men with pre-operative MSHQ data, 46/74 (62.1%) had difficulty with ejaculation, 25/35 (71%) had change in penile length, and 6/33 (18%) reported penile curvature. In men with post-operative MSHQ, 19/44 (43%) expressed difficulty with ejaculation, 23/32 (72%) had change in penile length, and 9/33 (27%) reported penile curvature. CONCLUSIONS: There is a high rate of severe ED, both following PFUI and remaining after posterior urethroplasty. Additionally, rates of ejaculatory difficulty and patient perceived changes in penile length and curvature underscore the complex nature of the impact of these injuries on sexual function beyond simple erectile function.

17.
Endocrinology ; 162(12)2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34192304

RESUMEN

Mutations in G protein-coupled receptors (GPCRs) underlie numerous diseases. Many cause receptor misfolding and failure to reach the cell surface. Pharmacological chaperones are cell-permeant small molecules that engage nascent mutant GPCRs in the endoplasmic reticulum, stabilizing folding and "rescuing" cell surface expression. We previously demonstrated rescue of cell surface expression of luteinizing hormone receptor mutants by an allosteric agonist. Here we demonstrate that a similar approach can be employed to rescue mutant follicle-stimulating hormone receptors (FSHRs) with poor cell surface expression using a small-molecule FSHR agonist, CAN1404. Seventeen FSHR mutations described in patients with reproductive dysfunction were expressed in HEK 293T cells, and cell surface expression was determined by enzyme-linked immunosorbent assay of epitope-tagged FSHRs before/after treatment with CAN1404. Cell surface expression was severely reduced to ≤18% of wild-type (WT) for 11, modestly reduced to 66% to 84% of WT for 4, and not reduced for 2. Of the 11 with severely reduced cell surface expression, restoration to ≥57% of WT levels was achieved for 6 by treatment with 1 µM CAN1404 for 24 h, and a corresponding increase in FSH-induced signaling was observed for 4 of these, indicating restored functionality. Therefore, CAN1404 acts as a pharmacological chaperone and can rescue cell surface expression and function of certain mutant FSHRs with severely reduced cell surface expression. These findings aid in advancing the understanding of the effects of genetic mutations on GPCR function and provide a proof of therapeutic principle for FSHR pharmacological chaperones.


Asunto(s)
Membrana Celular/metabolismo , Receptores de HFE/genética , Receptores de HFE/metabolismo , Animales , Células CHO , Membrana Celular/efectos de los fármacos , Membrana Celular/genética , Cricetinae , Cricetulus , Hormona Folículo Estimulante/farmacología , Células HEK293 , Humanos , Mutación con Pérdida de Función/genética , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutación , Receptores de HFE/agonistas , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética
18.
Neuroendocrinology ; 111(5): 451-464, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32316022

RESUMEN

INTRODUCTION: G protein-coupled receptor (GPCR) mutations are implicated in many diseases. Most inactivating mutations cause receptor misfolding and prevent trafficking to the plasma membrane. Pharmacological chaperones can "rescue" cell surface expression of such mutants, presumably by stabilising correct folding of the nascent protein. OBJECTIVE: Here we examine the scope of intracellularly retained luteinising hormone receptor (LHR) mutants that can be "rescued" by the pharmacological chaperone LHR-Chap, and whether this allosteric agonist can also restore the function of mutant LHRs with deficiencies in hormone binding or hormone-induced signalling. METHODS: Mutant LHRs were expressed in HEK 293-T cells. Cell surface expression/localisation, hormone binding, and hCG/LHR-Chap signalling were determined by ELISA, radioligand binding, and inositol phosphate accumulation assays, respectively. Molecular modelling predicted LHR-Chap interactions. RESULTS: LHR-Chap increased cell surface expression of a subset of retained mutants located in transmembrane helices predicted to be stabilised by LHR-Chap binding. For 3 (T4613.47I, L5024.61P, and S6167.46Y) hCG-responsiveness was increased following treatment. LHRs with mutations in the hormone-binding site (C131ECDR and I152ECDT) or in the hinge region (E354HingeK) had good cell surface expression but poor response to hormone stimulation, yet were responsive to allosteric activation by LHR-Chap. CONCLUSIONS: LHR-Chap, in addition to rescuing cell surface expression of intracellularly retained LHR mutants, can rescue function in mutant receptors with binding and signalling deficiencies that have normal cell surface expression. This demonstration of rescue of multiple elements of LHR dysfunction arising from inactivating mutations offers exceptional potential for treating patients with diseases arising from GPCR mutations in general.


Asunto(s)
Regulación Alostérica , Chaperonas Moleculares , Receptores de HL/agonistas , Células HEK293 , Humanos , Proteínas Mutantes , Mutación , Pliegue de Proteína
19.
Brain ; 144(2): 473-486, 2021 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-33301569

RESUMEN

No biomarker of Parkinson's disease exists that allows clinicians to adjust chronic therapy, either medication or deep brain stimulation, with real-time feedback. Consequently, clinicians rely on time-intensive, empirical, and subjective clinical assessments of motor behaviour and adverse events to adjust therapies. Accumulating evidence suggests that hypokinetic aspects of Parkinson's disease and their improvement with therapy are related to pathological neural activity in the beta band (beta oscillopathy) in the subthalamic nucleus. Additionally, effectiveness of deep brain stimulation may depend on modulation of the dorsolateral sensorimotor region of the subthalamic nucleus, which is the primary site of this beta oscillopathy. Despite the feasibility of utilizing this information to provide integrated, biomarker-driven precise deep brain stimulation, these measures have not been brought together in awake freely moving individuals. We sought to directly test whether stimulation-related improvements in bradykinesia were contingent on reduction of beta power and burst durations, and/or the volume of the sensorimotor subthalamic nucleus that was modulated. We recorded synchronized local field potentials and kinematic data in 16 subthalamic nuclei of individuals with Parkinson's disease chronically implanted with neurostimulators during a repetitive wrist-flexion extension task, while administering randomized different intensities of high frequency stimulation. Increased intensities of deep brain stimulation improved movement velocity and were associated with an intensity-dependent reduction in beta power and mean burst duration, measured during movement. The degree of reduction in this beta oscillopathy was associated with the improvement in movement velocity. Moreover, the reduction in beta power and beta burst durations was dependent on the theoretical degree of tissue modulated in the sensorimotor region of the subthalamic nucleus. Finally, the degree of attenuation of both beta power and beta burst durations, together with the degree of overlap of stimulation with the sensorimotor subthalamic nucleus significantly explained the stimulation-related improvement in movement velocity. The above results provide direct evidence that subthalamic nucleus deep brain stimulation-related improvements in bradykinesia are related to the reduction in beta oscillopathy within the sensorimotor region. With the advent of sensing neurostimulators, this beta oscillopathy combined with lead location could be used as a marker for real-time feedback to adjust clinical settings or to drive closed-loop deep brain stimulation in freely moving individuals with Parkinson's disease.


Asunto(s)
Ritmo beta , Estimulación Encefálica Profunda , Hipocinesia/diagnóstico , Hipocinesia/fisiopatología , Enfermedad de Parkinson/fisiopatología , Núcleo Subtalámico/fisiopatología , Adulto , Anciano , Fenómenos Biomecánicos , Femenino , Humanos , Hipocinesia/complicaciones , Masculino , Persona de Mediana Edad , Actividad Motora , Vías Nerviosas/fisiopatología , Enfermedad de Parkinson/complicaciones
20.
J Urol ; 205(3): 841-847, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33021435

RESUMEN

PURPOSE: The majority of high grade renal trauma can be managed conservatively. However, nephrectomy is still common for acute management. We hypothesized that when controlling for multiple injury severity measures, nephrectomy would be associated with increased mortality. MATERIALS AND METHODS: We identified high grade renal trauma patients from the National Trauma Data Bank® from 2007-2016. Exclusion criteria were age <18 years, severe head injury and death within 4 hours of admission. We performed conditional logistic regression analysis to determine if nephrectomy was independently associated with mortality, controlling for age, gender, race/ethnicity, mechanism of injury, shock, blood transfusion, Glasgow Coma Scale, Revised Trauma Score and Injury Severity Score. Interaction was measured for mechanism of injury and shock with mortality. RESULTS: We identified 42,898 patients with high grade renal trauma (grade III-V), of whom 3,204 (7.5%) underwent nephrectomy. Unadjusted mortality was 16.6% in nephrectomy vs 5.7% in nonnephrectomy patients. In multivariable logistic regression, nephrectomy was associated with 82% increased odds of death (OR 1.82, 95% CI 1.63-2.03, p <0.001). Other significant associations with death included age, nonWhite race, penetrating mechanism, hypotension, blood transfusion, lower Glasgow Coma Scale, lower Revised Trauma Score and higher Injury Severity Score. The association between nephrectomy and death did not differ by mechanism of injury. However, it was slightly attenuated in patients presenting in shock. CONCLUSIONS: In the National Trauma Data Bank, nephrectomy is independently associated with increased risk of mortality after adjusting for patient demographics, injury characteristics and multiple measures of overall injury severity. Nephrectomy may impact overall survival and must be avoided when possible.


Asunto(s)
Riñón/lesiones , Riñón/cirugía , Nefrectomía/mortalidad , Adulto , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Índices de Gravedad del Trauma , Estados Unidos/epidemiología
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