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1.
Development ; 150(14)2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37350382

RESUMEN

Retinoic acid (RA) is the proposed mammalian 'meiosis inducing substance'. However, evidence for this role comes from studies in the fetal ovary, where germ cell differentiation and meiotic initiation are temporally inseparable. In the postnatal testis, these events are separated by more than 1 week. Exploiting this difference, we discovered that, although RA is required for spermatogonial differentiation, it is dispensable for the subsequent initiation, progression and completion of meiosis. Indeed, in the absence of RA, the meiotic transcriptome program in both differentiating spermatogonia and spermatocytes entering meiosis was largely unaffected. Instead, transcripts encoding factors required during spermiogenesis were aberrant during preleptonema, and the subsequent spermatid morphogenesis program was disrupted such that no sperm were produced. Taken together, these data reveal a RA-independent model for male meiotic initiation.


Asunto(s)
Testículo , Tretinoina , Animales , Femenino , Masculino , Tretinoina/farmacología , Espermatogénesis/genética , Espermatogonias , Espermatozoides , Meiosis/genética , Mamíferos
2.
Development ; 149(22)2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36250451

RESUMEN

In mammalian testes, premeiotic spermatogonia respond to retinoic acid by completing an essential lengthy differentiation program before initiating meiosis. The molecular and cellular changes directing these developmental processes remain largely undefined. This wide gap in knowledge is due to two unresolved technical challenges: (1) lack of robust and reliable in vitro models to study differentiation and meiotic initiation; and (2) lack of methods to isolate large and pure populations of male germ cells at each stage of differentiation and at meiotic initiation. Here, we report a facile in vitro differentiation and meiotic initiation system that can be readily manipulated, including the use of chemical agents that cannot be safely administered to live animals. In addition, we present a transgenic mouse model enabling fluorescence-activated cell sorting-based isolation of millions of spermatogonia at specific developmental stages as well as meiotic spermatocytes.


Asunto(s)
Espermatogénesis , Espermatogonias , Masculino , Ratones , Animales , Espermatocitos , Testículo , Meiosis , Diferenciación Celular , Ratones Transgénicos , Mamíferos
3.
PLoS Genet ; 18(9): e1010416, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36129965

RESUMEN

Control over gene expression is exerted, in multiple stages of spermatogenesis, at the post-transcriptional level by RNA binding proteins (RBPs). We identify here an essential role in mammalian spermatogenesis and male fertility for 'RNA binding protein 46' (RBM46). A highly evolutionarily conserved gene, Rbm46 is also essential for fertility in both flies and fish. We found Rbm46 expression was restricted to the mouse germline, detectable in males in the cytoplasm of premeiotic spermatogonia and meiotic spermatocytes. To define its requirement for spermatogenesis, we generated Rbm46 knockout (KO, Rbm46-/-) mice; although male Rbm46-/- mice were viable and appeared grossly normal, they were infertile. Testes from adult Rbm46-/- mice were small, with seminiferous tubules containing only Sertoli cells and few undifferentiated spermatogonia. Using genome-wide unbiased high throughput assays RNA-seq and 'enhanced crosslinking immunoprecipitation' coupled with RNA-seq (eCLIP-seq), we discovered RBM46 could bind, via a U-rich conserved consensus sequence, to a cohort of mRNAs encoding proteins required for completion of differentiation and subsequent meiotic initiation. In summary, our studies support an essential role for RBM46 in regulating target mRNAs during spermatogonia differentiation prior to the commitment to meiosis in mice.


Asunto(s)
Proteínas de Unión al ARN/metabolismo , Espermatogénesis , Espermatogonias , Animales , Diferenciación Celular/genética , Masculino , Mamíferos/genética , Meiosis/genética , Ratones , Ratones Noqueados , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/genética , Espermatocitos/metabolismo , Espermatogénesis/genética , Espermatogonias/metabolismo , Testículo
4.
Alzheimers Dement ; 20(7): 5062-5070, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38829682

RESUMEN

INTRODUCTION: Altered immune signatures are emerging as a central theme in neurodegenerative disease, yet little is known about immune responses in early-onset Alzheimer's disease (EOAD). METHODS: We examined single-cell RNA-sequencing (scRNA-seq) data from peripheral blood mononuclear cells (PBMCs) and droplet digital polymerase chain reaction (ddPCR) data from CD4 T cells from participants with EOAD and clinically normal controls. RESULTS: We analyzed PBMCs from 16 individuals by scRNA-seq and discovered increased interferon signaling-associated gene (ISAG) expression and striking expansion of antiviral-like ISAGhi T cells in EOAD. Isolating CD4 T cells from 19 individuals, including four cases analyzed by scRNA-seq, we confirmed increased expression of ISAGhi marker genes. Publicly available cerebrospinal fluid leukocyte scRNA-seq data from late-onset mild cognitive impairment and AD also revealed increased expression of interferon-response genes. DISCUSSION: Antiviral-like ISAGhi T cells are expanded in EOAD. Additional research into these cells and the role of heightened peripheral IFN signaling in neurodegeneration is warranted. HIGHLIGHTS: Interferon-responsive T cells expanded in early-onset Alzheimer's disease (AD). Increased interferon-associated gene expression present in early- and late-onset AD. Peripheral immune changes in T and NK cells driven by females with early-onset AD.


Asunto(s)
Enfermedad de Alzheimer , Interferones , Humanos , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/inmunología , Femenino , Masculino , Persona de Mediana Edad , Linfocitos T CD4-Positivos , Leucocitos Mononucleares/metabolismo , Anciano
5.
Eur J Orthop Surg Traumatol ; 34(2): 1173-1181, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37989870

RESUMEN

PURPOSE: To determine if incisional negative pressure wound therapy is protective against post-operative surgical site complications following definitive fixation of bicondylar tibial plateau fractures. METHODS: A retrospective analysis of patients diagnosed with an acute bicondylar tibial plateau fracture (AO/OTA 41-C) undergoing ORIF from 2010 to 2020 was performed. Patients received either a standard sterile dressing (SD) or incisional negative pressure wound therapy (iNPWT). Primary outcomes included surgical site infection, osteomyelitis, and wound dehiscence. Secondary outcomes included non-union and return to the operating room. Multivariate logistic regression analyses were performed. RESULTS: 180 patients were included and 22% received iNPWT (n = 40) and 78% received standard dressings (n = 140). iNPWT was more common in active smokers (24.7% vs. 19.3%, p = 0.002) and the SD group was more likely to be lost to follow up (3.6% vs. 0%, p = 0.025). iNPWT was not protective against infection or surgical site complications, and in fact, was associated with higher odds of post-operative infection (OR: 8.96, p = 0.005) and surgical site complications (OR:4.874, p = 0.009) overall. Alcohol abuse (OR: 19, p = 0.005), tobacco use (OR: 4.67, p = 0.009), and time to definitive surgery (OR = 1.21, p = 0.033) were all independent risk factors for post-operative infection. CONCLUSION: In this series of operatively treated bicondylar tibial plateau fractures, iNPWT did not protect against post-operative surgical site complications compared to conventional dressings. Tobacco use, alcohol abuse, and time to definitive surgery, were independent risk factors for post-operative infection. Further studies are needed to determine if iNPWT offers a protective benefit in exclusively high-risk patients with relevant medical and social history.


Asunto(s)
Alcoholismo , Terapia de Presión Negativa para Heridas , Fracturas de la Tibia , Fracturas de la Meseta Tibial , Humanos , Estudios Retrospectivos , Alcoholismo/etiología , Fracturas de la Tibia/cirugía , Fracturas de la Tibia/etiología , Fijación Interna de Fracturas/efectos adversos , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/prevención & control
6.
Eur J Orthop Surg Traumatol ; 34(1): 231-236, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37428226

RESUMEN

PURPOSE: Proximal femoral osteotomy (PFO) with periacetabular osteotomy (PAO) improves femoral head coverage in patients with proximal femoral and acetabular dysplasia. Historically, blade plates used in the PFO cause soft-tissue irritation and often lead to implant removal. Here we present a technique using a lower profile pediatric proximal femoral locking compression plate (LCP) for the PFO in a series of adults. METHODS: The results from 13 hips in 11 patients ≥ 18 years old (age 18-37) with > 10 months of follow-up are presented. RESULTS: All patients had improved radiographic parameters, pain, and total Merle d'Aubigné-Postel scores postoperatively. Eleven hips (85%) had the LCP removed an average of 15.8 ± 8.6 months postoperatively, often due to pain over the greater trochanter. CONCLUSION: The pediatric proximal femoral LCP is effective for PFO in combined PAO PFO procedures but has a high rate of lateral hip discomfort leading to implant removal.


Asunto(s)
Luxación Congénita de la Cadera , Luxación de la Cadera , Adulto , Humanos , Niño , Adolescente , Adulto Joven , Articulación de la Cadera/cirugía , Estudios Retrospectivos , Luxación Congénita de la Cadera/cirugía , Luxación de la Cadera/cirugía , Fémur/diagnóstico por imagen , Fémur/cirugía , Osteotomía/métodos , Dolor , Acetábulo/cirugía , Resultado del Tratamiento
7.
J Physiol ; 601(11): 2189-2216, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35924591

RESUMEN

Impaired mitochondrial function and disrupted proteostasis contribute to musculoskeletal dysfunction. However, few interventions simultaneously target these two drivers to prevent musculoskeletal decline. Nuclear factor erythroid 2-related factor 2 (Nrf2) activates a transcriptional programme promoting cytoprotection, metabolism, and proteostasis. We hypothesized daily treatment with a purported Nrf2 activator, PB125, in Hartley guinea pigs, a model of musculoskeletal decline, would attenuate the progression of skeletal muscle mitochondrial dysfunction and impaired proteostasis and preserve musculoskeletal function. We treated 2- and 5-month-old male and female Hartley guinea pigs for 3 and 10 months, respectively, with the phytochemical compound PB125. Longitudinal assessments of voluntary mobility were measured using Any-MazeTM open-field enclosure monitoring. Cumulative skeletal muscle protein synthesis rates were measured using deuterium oxide over the final 30 days of treatment. Mitochondrial oxygen consumption in soleus muscles was measured using high resolution respirometry. In both sexes, PB125 (1) increased electron transfer system capacity; (2) attenuated the disease/age-related decline in coupled and uncoupled mitochondrial respiration; and (3) attenuated declines in protein synthesis in the myofibrillar, mitochondrial and cytosolic subfractions of the soleus. These effects were not associated with statistically significant prolonged maintenance of voluntary mobility in guinea pigs. Collectively, treatment with PB125 contributed to maintenance of skeletal muscle mitochondrial respiration and proteostasis in a pre-clinical model of musculoskeletal decline. Further investigation is necessary to determine if these documented effects of PB125 are also accompanied by slowed progression of other aspects of musculoskeletal dysfunction. KEY POINTS: Aside from exercise, there are no effective interventions for musculoskeletal decline, which begins in the fifth decade of life and contributes to disability and cardiometabolic diseases. Targeting both mitochondrial dysfunction and impaired protein homeostasis (proteostasis), which contribute to the age and disease process, may mitigate the progressive decline in overall musculoskeletal function (e.g. gait, strength). A potential intervention to target disease drivers is to stimulate nuclear factor erythroid 2-related factor 2 (Nrf2) activation, which leads to the transcription of genes responsible for redox homeostasis, proteome maintenance and mitochondrial energetics. Here, we tested a purported phytochemical Nrf2 activator, PB125, to improve mitochondrial function and proteostasis in male and female Hartley guinea pigs, which are a model for musculoskeletal ageing. PB125 improved mitochondrial respiration and attenuated disease- and age-related declines in skeletal muscle protein synthesis, a component of proteostasis, in both male and female Hartley guinea pigs.


Asunto(s)
Factor 2 Relacionado con NF-E2 , Proteostasis , Masculino , Femenino , Animales , Cobayas , Factor 2 Relacionado con NF-E2/metabolismo , Músculo Esquelético/fisiología , Mitocondrias/metabolismo , Envejecimiento/fisiología
8.
Biol Reprod ; 108(5): 822-836, 2023 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-36708226

RESUMEN

The foundation of mammalian spermatogenesis is provided by undifferentiated spermatogonia, which comprise of spermatogonial stem cells (SSCs) and transit-amplifying progenitors that differentiate in response to retinoic acid (RA) and are committed to enter meiosis. Our laboratory recently reported that the foundational populations of SSCs, undifferentiated progenitors, and differentiating spermatogonia are formed in the neonatal testis in part based on their differential responsiveness to RA. Here, we expand on those findings to define the extent to which RA responsiveness during steady-state spermatogenesis in the adult testis regulates the spermatogonial fate. Our results reveal that both progenitor and differentiating spermatogonia throughout the testis are capable of responding to exogenous RA, but their resulting fates were quite distinct-undifferentiated progenitors precociously differentiated and proceeded into meiosis on a normal timeline, while differentiating spermatogonia were unable to hasten their entry into meiosis. This reveals that the spermatogonia responding to RA must still complete the 8.6 day differentiation program prior to their entry into meiosis. Addition of exogenous RA enriched testes with preleptotene and pachytene spermatocytes one and two seminiferous cycles later, respectively, supporting recent clinical studies reporting increased sperm production and enhanced fertility in subfertile men on long-term RA analog treatment. Collectively, our results reveal that a well-buffered system exists within mammalian testes to regulate spermatogonial RA exposure, that exposed undifferentiated progenitors can precociously differentiate, but must complete a normal-length differentiation program prior to entering meiosis, and that daily RA treatments increased the numbers of advanced germ cells by directing undifferentiated progenitors to continuously differentiate.


Asunto(s)
Espermatogonias , Tretinoina , Animales , Recién Nacido , Masculino , Humanos , Tretinoina/farmacología , Semen , Espermatogénesis/fisiología , Testículo , Diferenciación Celular/fisiología , Mamíferos
9.
Mol Psychiatry ; 27(6): 2674-2688, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35393555

RESUMEN

Early-onset Alzheimer's disease (EOAD) is a rare but particularly devastating form of AD. Though notable for its high degree of clinical heterogeneity, EOAD is defined by the same neuropathological hallmarks underlying the more common, late-onset form of AD. In this review, we describe the various clinical syndromes associated with EOAD, including the typical amnestic phenotype as well as atypical variants affecting visuospatial, language, executive, behavioral, and motor functions. We go on to highlight advances in fluid biomarker research and describe how molecular, structural, and functional neuroimaging can be used not only to improve EOAD diagnostic acumen but also enhance our understanding of fundamental pathobiological changes occurring years (and even decades) before the onset of symptoms. In addition, we discuss genetic variation underlying EOAD, including pathogenic variants responsible for the well-known mendelian forms of EOAD as well as variants that may increase risk for the much more common forms of EOAD that are either considered to be sporadic or lack a clear autosomal-dominant inheritance pattern. Intriguingly, specific pathogenic variants in PRNP and MAPT-genes which are more commonly associated with other neurodegenerative diseases-may provide unexpectedly important insights into the formation of AD tau pathology. Genetic analysis of the atypical clinical syndromes associated with EOAD will continue to be challenging given their rarity, but integration of fluid biomarker data, multimodal imaging, and various 'omics techniques and their application to the study of large, multicenter cohorts will enable future discoveries of fundamental mechanisms underlying the development of EOAD and its varied clinical presentations.


Asunto(s)
Enfermedad de Alzheimer , Edad de Inicio , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Humanos , Lenguaje , Estudios Multicéntricos como Asunto , Fenotipo , Síndrome
10.
Eye Contact Lens ; 49(5): 212-218, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36888541

RESUMEN

ABSTRACT: Infectious keratitis is a devastating cause of vision loss worldwide. Cutibacterium acnes ( C. acnes ), a commensal bacterium of the skin and ocular surface, is an underrecognized but important cause of bacterial keratitis. This review presents the most comprehensive and up-to-date information for clinicians regarding the risk factors, incidence, diagnosis, management, and prognosis of C. acnes keratitis (CAK). Risk factors are similar to those of general bacterial keratitis and include contact lens use, past ocular surgery, and trauma. The incidence of CAK may be approximately 10%, ranging from 5% to 25% in growth-positive cultures. Accurate diagnosis requires anaerobic blood agar and a long incubation period (≥7 days). Typical clinical presentation includes small (<2 mm) ulcerations with deep stromal infiltrate causing an anterior chamber cell reaction. Small, peripheral lesions are usually resolved, and patients recover a high visual acuity. Severe infections causing VA of 20/200 or worse are common and often do not significantly improve even after treatment. Vancomycin is considered the most potent antibiotic against CAK, although other antibiotics such as moxifloxacin and ceftazidime are more commonly used as first-line treatment.


Asunto(s)
Infecciones Bacterianas del Ojo , Infecciones por Bacterias Grampositivas , Queratitis , Humanos , Propionibacterium acnes , Queratitis/diagnóstico , Queratitis/tratamiento farmacológico , Antibacterianos/uso terapéutico , Infecciones Bacterianas del Ojo/diagnóstico , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Ceftazidima/uso terapéutico , Infecciones por Bacterias Grampositivas/diagnóstico , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/microbiología
11.
Int J Mol Sci ; 24(13)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37446371

RESUMEN

Post-traumatic stress disorder (PTSD) is a complex stress-related disorder induced by exposure to traumatic stress that is characterized by symptoms of re-experiencing, avoidance, and hyper-arousal. While it is widely accepted that brain regions involved in emotional regulation and memory-e.g., the amygdala and hippocampus-are dysregulated in PTSD, the pathophysiology of the disorder is not well defined and therefore, pharmacological interventions are extremely limited. Because stress hormones norepinephrine and cortisol (corticosterone in rats) are heavily implicated in the disorder, we explored whether preemptively and systemically antagonizing ß-adrenergic and glucocorticoid receptors with propranolol and mifepristone are sufficient to mitigate pathological changes in synaptic plasticity, gene expression, and anxiety induced by a modified social defeat (SD) stress protocol. Young adult, male Sprague Dawley rats were initially pre-screened for anxiety. The rats were then exposed to SD and chronic light stress to induce anxiety-like symptoms. Drug-treated rats were administered propranolol and mifepristone injections prior to and continuing throughout SD stress. Using competitive ELISAs on plasma, field electrophysiology at CA1 of the ventral hippocampus (VH) and the basolateral amygdala (BLA), quantitative RT-PCR, and behavior assays, we demonstrate that our SD stress increased anxiety-like behavior, elevated long-term potentiation (LTP) in the VH and BLA, and altered the expression of mineralocorticoid, glucocorticoid, and glutamate receptors. These measures largely reverted to control levels with the administration of propranolol and mifepristone. Our findings indicate that SD stress increases LTP in the VH and BLA and that prophylactic treatment with propranolol and mifepristone may have the potential in mitigating these and other stress-induced effects.


Asunto(s)
Mifepristona , Roedores , Ratas , Masculino , Animales , Mifepristona/farmacología , Ratas Sprague-Dawley , Propranolol/farmacología , Derrota Social , Hipocampo/metabolismo , Plasticidad Neuronal , Amígdala del Cerebelo/metabolismo , Expresión Génica , Estrés Psicológico/complicaciones
12.
Angew Chem Int Ed Engl ; 61(46): e202209518, 2022 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-36283971

RESUMEN

Manley and co-workers provide data demonstrating that, at super-pharmacological concentrations (300 µM), a ternary complex between Abl, asciminib, and ATP-competitive inhibitors is possible. The work in our manuscript concerns the interplay of asciminib (and GNF-2) with ATP-competitive inhibitors at pharmacologically relevant concentrations (Cmax =1.6-3.7 µM for asciminib). Manley and co-workers do not question any of the studies that we reported, nor do they provide explanations for how our work fits into their preferred model. Herein, we consider the data presented by Manley and co-workers. In addition, we provide new data supporting the findings in our Communication. Asciminib and ATP-competitive inhibitors do not simultaneously bind Abl at pharmacologically relevant concentrations unless the conformation selectivity for both ligands is matched.


Asunto(s)
Resistencia a Antineoplásicos , Proteínas Proto-Oncogénicas c-abl , Humanos , Adenosina Trifosfato/metabolismo , Conformación Molecular , Mutación , Proteínas Proto-Oncogénicas c-abl/antagonistas & inhibidores
13.
Biol Reprod ; 105(6): 1603-1616, 2021 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-34518881

RESUMEN

Aurora A kinase (AURKA) is an important regulator of cell division and is required for assembly of the mitotic spindle. We recently reported the unusual finding that this mitotic kinase is also found on the sperm flagellum. To determine its requirement in spermatogenesis, we generated conditional knockout animals with deletion of the Aurka gene in either spermatogonia or spermatocytes to assess its role in mitotic and postmitotic cells, respectively. Deletion of Aurka in spermatogonia resulted in disappearance of all developing germ cells in the testis, as expected, given its vital role in mitotic cell division. Deletion of Aurka in spermatocytes reduced testis size, sperm count, and fertility, indicating disruption of meiosis or an effect on spermiogenesis in developing mice. Interestingly, deletion of Aurka in spermatocytes increased apoptosis in spermatocytes along with an increase in the percentage of sperm with abnormal morphology. Despite the increase in abnormal sperm, sperm from spermatocyte Aurka knockout mice displayed increased progressive motility. In addition, sperm lysate prepared from Aurka knockout animals had decreased protein phosphatase 1 (PP1) activity. Together, our results show that AURKA plays multiple roles in spermatogenesis, from mitotic divisions of spermatogonia to sperm morphology and motility.


Asunto(s)
Aurora Quinasa A/genética , Ratones/fisiología , Motilidad Espermática/genética , Espermatozoides/enzimología , Testículo/crecimiento & desarrollo , Animales , Aurora Quinasa A/deficiencia , Aurora Quinasa A/metabolismo , Masculino , Ratones/genética , Ratones Noqueados , Espermatogénesis/genética
14.
Molecules ; 26(24)2021 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-34946596

RESUMEN

Background: Radionuclides emitting Auger electrons (AEs) with low (0.02-50 keV) energy, short (0.0007-40 µm) range, and high (1-10 keV/µm) linear energy transfer may have an important role in the targeted radionuclide therapy of metastatic and disseminated disease. Erbium-165 is a pure AE-emitting radionuclide that is chemically matched to clinical therapeutic radionuclide 177Lu, making it a useful tool for fundamental studies on the biological effects of AEs. This work develops new biomedical cyclotron irradiation and radiochemical isolation methods to produce 165Er suitable for targeted radionuclide therapeutic studies and characterizes a new such agent targeting prostate-specific membrane antigen. Methods: Biomedical cyclotrons proton-irradiated spot-welded Ho(m) targets to produce 165Er, which was isolated via cation exchange chromatography (AG 50W-X8, 200-400 mesh, 20 mL) using alpha-hydroxyisobutyrate (70 mM, pH 4.7) followed by LN2 (20-50 µm, 1.3 mL) and bDGA (50-100 µm, 0.2 mL) extraction chromatography. The purified 165Er was radiolabeled with standard radiometal chelators and used to produce and characterize a new AE-emitting radiopharmaceutical, [165Er]PSMA-617. Results: Irradiation of 80-180 mg natHo targets with 40 µA of 11-12.5 MeV protons produced 165Er at 20-30 MBq·µA-1·h-1. The 4.9 ± 0.7 h radiochemical isolation yielded 165Er in 0.01 M HCl (400 µL) with decay-corrected (DC) yield of 64 ± 2% and a Ho/165Er separation factor of (2.8 ± 1.1) · 105. Radiolabeling experiments synthesized [165Er]PSMA-617 at DC molar activities of 37-130 GBq·µmol-1. Conclusions: A 2 h biomedical cyclotron irradiation and 5 h radiochemical separation produced GBq-scale 165Er suitable for producing radiopharmaceuticals at molar activities satisfactory for investigations of targeted radionuclide therapeutics. This will enable fundamental radiation biology experiments of pure AE-emitting therapeutic radiopharmaceuticals such as [165Er]PSMA-617, which will be used to understand the impact of AEs in PSMA-targeted radionuclide therapy of prostate cancer.


Asunto(s)
Dipéptidos/química , Erbio/química , Compuestos Heterocíclicos con 1 Anillo/química , Antígeno Prostático Específico/química , Neoplasias de la Próstata/radioterapia , Radioisótopos/química , Radiofármacos/química , Humanos , Masculino
15.
Angew Chem Int Ed Engl ; 60(37): 20196-20199, 2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34292655

RESUMEN

Allosteric inhibitors of Abl kinase are being explored in the clinic, often in combination with ATP-site inhibitors of Abl kinase. However, there are conflicting data on whether both ATP-competitive inhibitors and myristoyl-site allosteric inhibitors can simultaneously bind Abl kinase. Here, we determine whether there is synergy or antagonism between ATP-competitive inhibitors and allosteric inhibitors of Abl. We observe that clinical ATP-competitive inhibitors are not synergistic with allosteric ABL inhibitors, however, conformation-selective ATP-site inhibitors that modulate the global conformation of Abl can afford synergy. We demonstrate that kinase conformation is the key driver to simultaneously bind two compounds to Abl kinase. Finally, we explore the interaction of allosteric and conformation selective ATP-competitive inhibitors in a series of biochemical and cellular assays.


Asunto(s)
Adenosina Trifosfato/farmacología , Proteínas de Fusión bcr-abl/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Adenosina Trifosfato/química , Dominio Catalítico/efectos de los fármacos , Proteínas de Fusión bcr-abl/metabolismo , Humanos , Modelos Moleculares , Inhibidores de Proteínas Quinasas/química
16.
Biol Reprod ; 103(5): 1132-1143, 2020 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-32716476

RESUMEN

Sirolimus, also known as rapamycin, and its closely related rapamycin analog (rapalog) Everolimus inhibit "mammalian target of rapamycin complex 1" (mTORC1), whose activity is required for spermatogenesis. Everolimus is Food and Drug Administration approved for treating human patients to slow growth of aggressive cancers and preventing organ transplant rejection. Here, we test the hypothesis that rapalog inhibition of mTORC1 activity has a negative, but reversible, impact upon spermatogenesis. Juvenile (P20) or adult (P>60) mice received daily injections of sirolimus or Everolimus for 30 days, and tissues were examined at completion of treatment or following a recovery period. Rapalog treatments reduced body and testis weights, testis weight/body weight ratios, cauda epididymal sperm counts, and seminal vesicle weights in animals of both ages. Following rapalog treatment, numbers of differentiating spermatogonia were reduced, with concomitant increases in the ratio of undifferentiated spermatogonia to total number of remaining germ cells. To determine if even low doses of Everolimus can inhibit spermatogenesis, an additional group of adult mice received a dose of Everolimus ∼6-fold lower than a human clinical dose used to treat cancer. In these animals, only testis weights, testis weight/body weight ratios, and tubule diameters were reduced. Return to control values following a recovery period was variable for each of the measured parameters and was duration and dose dependent. Together, these data indicate rapalogs exerted a dose-dependent restriction on overall growth of juvenile and adult mice and negative impact upon spermatogenesis that were largely reversed; following treatment cessation, males from all treatment groups were able to sire offspring.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Everolimus/farmacología , Fertilidad/efectos de los fármacos , Espermatogénesis/efectos de los fármacos , Espermatogonias/efectos de los fármacos , Animales , Masculino , Ratones
17.
Prev Med ; 141: 106281, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33038359

RESUMEN

Firearms are a leading cause of death and injury in the United States, and this trend has continued during the COVID-19 pandemic. We sought to identify whether states designated gun retailers as essential businesses in their stay-at-home orders and characterize other references that could affect firearm acquisition during the COVID-19 pandemic. In this cross-sectional policy review, we assessed stay-at-home orders issued in March or April 2020. Orders were reviewed in their entirety, and any reference to firearms, firearm retailers, shooting ranges, or other relevant elements was documented. Forty-three states and the District of Columbia issued stay-at-home orders. Most considered federal firearm licensees to be among essential businesses or made provisions for them to remain open during widespread business closures. Others referenced the US Department of Homeland Security's Cybersecurity and Infrastructure Security Agency (CISA) advisory memorandum on essential critical infrastructure workers which named workers supporting firearm manufacturing and retail among essential workers. Therefore, stay-at-home orders issued in most states included provisions for firearms retailers to remain open, at least in some capacity. Only four states and the District of Columbia did not include federal firearms licensees among essential businesses or include provisions for them to be open. Meanwhile, an all-time high in firearm background checks indicates firearm sales have markedly increased. Given the associations between firearm access and injury risk, the effects of continued firearm access facilitated by these orders should be the focus of future research.


Asunto(s)
COVID-19/prevención & control , Armas de Fuego/estadística & datos numéricos , Armas de Fuego/normas , Concesión de Licencias/normas , Pandemias/prevención & control , Cuarentena/estadística & datos numéricos , Cuarentena/normas , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Guías como Asunto , Humanos , Concesión de Licencias/estadística & datos numéricos , Masculino , Persona de Mediana Edad , SARS-CoV-2 , Estados Unidos
18.
Retina ; 40(5): 825-832, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-30789460

RESUMEN

PURPOSE: To establish the prevalence and risk factors for intravitreal dexamethasone implant migration into the anterior chamber in eyes with macular edema. METHODS: This was a multicenter, retrospective, observational chart review of data that included patients with macular edema who had been treated with at least one intravitreal dexamethasone injection. Patients with incomplete chart information during the follow-up period were excluded. RESULTS: The prevalence of implant migration in 468 patients, considering the number of injections, was 1.6%, with significant associations between implant migration and cataract surgery (P = 0.043) and intraocular lens status (P = 0.005) and a trend toward statistical significance (P = 0.057) with vitrectomy. A higher rate of implant migration into the anterior chamber was observed in vitrectomized eyes (4.8%) when compared with patients who did not undergo a vitrectomy (1.6%). The implants that migrated were removed with forceps with/without viscoelastic expression or with 20-gauge cannulas connected to the vitreous cutter machine. CONCLUSION: The risk of implant migration into the anterior chamber was 1.6%. Risk factors were a history of cataract surgery or vitrectomy and aphakia. When anterior migration occurs, rapid removal is advised, especially if corneal edema is present.


Asunto(s)
Cámara Anterior , Dexametasona/administración & dosificación , Implantes de Medicamentos/efectos adversos , Migración de Cuerpo Extraño/diagnóstico , Agudeza Visual , Anciano , Femenino , Migración de Cuerpo Extraño/epidemiología , Glucocorticoides/administración & dosificación , Humanos , Incidencia , Inyecciones Intravítreas , Edema Macular/diagnóstico , Edema Macular/tratamiento farmacológico , Masculino , Estudios Retrospectivos , Estados Unidos/epidemiología
19.
Infect Immun ; 87(12)2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31548326

RESUMEN

The type IV pilus (Tfp) of nontypeable Haemophilus influenzae (NTHI) mediates adherence, colonization, motility, and biofilm formation, and the major protein subunit, PilA, is a promising vaccine candidate. Thus, it is crucial to understand how Tfp expression is regulated within the microenvironments of the human nasopharynx, which NTHI colonizes asymptomatically, and the more distal regions of the respiratory tract where NTHI-induced diseases occur. Here, we examined the effects of coculture of NTHI with human airway epithelial cells and heme availability on Tfp expression at temperatures typical of the human nasopharynx (34°C) or warmer anatomical sites during infection (37°C). Tfp expression was estimated by pilA promoter activity, pilA gene expression, and relative abundances of PilA and pilin protein. The results revealed that at both temperatures, NTHI cocultured with airway epithelial cells demonstrated significantly greater expression of pilA, PilA/pilin protein, and likely, fully assembled Tfp than NTHI cultured on an abiotic surface. Because NTHI is a heme auxotroph, we hypothesized that availability of heme from host cells might be a signal for Tfp expression. Thereby, we cultured NTHI in iron-limited medium, and we observed that supplementation with heme significantly increased pilA promoter activity. Collectively, our data suggested that NTHI Tfp expression was stimulated by soluble factor(s) released by epithelial cells, which are present in all microenvironments of the respiratory tract. The expression of this target antigen under conditions that mimic the human airway strongly supports the rationale for the use of PilA as a vaccine immunogen to prevent NTHI-induced diseases of the respiratory tract.


Asunto(s)
Proteínas Fimbrias/biosíntesis , Proteínas Fimbrias/inmunología , Fimbrias Bacterianas/inmunología , Haemophilus influenzae/inmunología , Nasofaringe/inmunología , Adhesión Bacteriana/genética , Vacunas Bacterianas/inmunología , Células Cultivadas , Técnicas de Cocultivo , Células Epiteliales/inmunología , Células Epiteliales/metabolismo , Proteínas Fimbrias/genética , Fimbrias Bacterianas/metabolismo , Infecciones por Haemophilus/inmunología , Infecciones por Haemophilus/microbiología , Hemo/metabolismo , Humanos , Nasofaringe/microbiología , Regiones Promotoras Genéticas/genética , Sistema Respiratorio/citología
20.
Can J Urol ; 26(3): 9763-9768, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31180306

RESUMEN

INTRODUCTION: To assess the secondary sequence rule in The Prostate Imaging Reporting Data System (PI-RADS) version 2 by comparing the detection of Grade group 1+ (GG1+) and 2+ (GG2+) cancers in PI-RADS 3, an upgraded PI-RADS 4, and true (non-upgraded) PI-RADS 4 targets. MATERIALS AND METHODS: We analyzed a total of 589 lesions scored as PI-RADS 3 or 4 obtained from 434 men who underwent mpMRI-US fusion biopsy from September 2015 to November 2017 for evaluation of GG1+ and GG2+ prostate cancer. PI-RADS 4 lesions were differentiated into those that were 'upgraded' to PI-RADS 4 based on the secondary sequence and those that were 'true' PI-RADS 4 based on the dominant sequence. RESULTS: The odds of detecting a GG2+ cancer was significantly higher for an upgraded 4 (peripheral zone (PZ): OR 5.06, 95%CI 2.04-12.54, p < 0.001, transitional zone (TZ): OR 3.08, 95%CI 1.04-9.08, p = 0.042) and true 4 (PZ: OR 5.82, 95%CI 3.10-10.94, p < 0.0001, TZ: OR 2.43, 95%CI 1.14-5.18, p = 0.022) lesions compared to PI-RADS 3 lesions. Additionally, we found no difference in the odds of detecting a GG2+ prostate cancer between a true PI-RADS 4 (OR 1.15, 95%CI 0.49-2.71 p = 0.746) and upgraded 4 (referent) in the PZ. Similar non-significance was noted between true 4 (OR 0.79, 95%CI 0.26-2.38 p = 0.674) and upgraded 4 lesions in the TZ for detection of GG2+ cancers. CONCLUSIONS: Upgraded PI-RADS 4 and true 4 targets have a higher odds of detecting GG1+ and GG2+ compared to PI-RADS 3 in the PZ and TZ. Our findings validate the revised scoring system for PI-RADS.


Asunto(s)
Biopsia Guiada por Imagen/métodos , Imagen por Resonancia Magnética/métodos , Clasificación del Tumor/métodos , Próstata/patología , Neoplasias de la Próstata/diagnóstico , Sistemas de Información Radiológica/estadística & datos numéricos , Anciano , Humanos , Masculino , Neoplasias de la Próstata/clasificación , Reproducibilidad de los Resultados , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
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