RESUMEN

Quantifying viral growth rates is key to understanding evolutionary dynamics and the potential for mutants to escape antiviral drugs. Defining evolutionary escape paths and their impact on viral fitness allows for the development of drugs that are resistant to escape. In the case of HIV, combination antiretroviral therapy can successfully prevent or treat infection, but it relies on strict adherence to prevent escape. Here, we present a method termed QuickFit that enables the quantification of viral fitness by employing large numbers of parallel viral cultures to measure growth rates accurately. QuickFit consistently recapitulated HIV growth measurements obtained by traditional approaches, but with significantly higher throughput and lower rates of error. This method represents a promising tool for rapid and consistent evaluation of viral fitness.

Asunto(s)

Replicación Viral , Humanos , Ensayos Analíticos de Alto Rendimiento/métodos , VIH-1/genética , VIH-1/fisiología , VIH-1/crecimiento & desarrollo , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Aptitud Genética , Infecciones por VIH/virología , Infecciones por VIH/tratamiento farmacológico , VIH/genética , VIH/fisiología , VIH/crecimiento & desarrollo , Línea Celular

RESUMEN

The rise of ß-lactam resistance necessitates new strategies to combat bacterial infections. We purposefully engineered the ß-lactam prodrug AcephPT to exploit ß-lactamase activity to selectively suppress resistant bacteria producing extended-spectrum-ß-lactamases (ESBLs). Selective targeting of resistant bacteria requires avoiding interaction with penicillin-binding proteins, the conventional targets of ß-lactam antibiotics, while maintaining recognition by ESBLs to activate AcephPT only in resistant cells. Computational approaches provide a rationale for structural modifications to the prodrug to achieve this biased activity. We show AcephPT selectively suppresses gram-negative ESBL-producing bacteria in clonal populations and in mixed microbial cultures, with effective selectivity for both lab strains and clinical isolates expressing ESBLs. Time-course NMR experiments confirm hydrolytic activation of AcephPT exclusively by ESBL-producing bacteria. In mixed microbial cultures, AcephPT suppresses proliferation of ESBL-producing strains while sustaining growth of ß-lactamase-non-producing bacteria, highlighting its potential to combat ß-lactam resistance while promoting antimicrobial stewardship.

RESUMEN

Cellular and molecular characterization of immune responses elicited by influenza virus infection and seasonal vaccination have informed efforts to improve vaccine efficacy, breadth, and longevity. Here, we use negative stain electron microscopy polyclonal epitope mapping (nsEMPEM) to structurally characterize the humoral IgG antibody responses to hemagglutinin (HA) from human patients vaccinated with a seasonal quadrivalent flu vaccine or infected with influenza A viruses. Our data show that both vaccinated and infected patients had humoral IgGs targeting highly conserved regions on both H1 and H3 subtype HAs, including the stem and anchor, which are targets for universal influenza vaccine design. Responses against H1 predominantly targeted the central stem epitope in infected patients and vaccinated donors, whereas head epitopes were more prominently targeted on H3. Responses against H3 were less abundant, but a greater diversity of H3 epitopes were targeted relative to H1. While our analysis is limited by sample size, on average, vaccinated donors responded to a greater diversity of epitopes on both H1 and H3 than infected patients. These data establish a baseline for assessing polyclonal antibody responses in vaccination and infection, providing context for future vaccine trials and emphasizing the importance of carefully designing vaccines to boost protective responses towards conserved epitopes.

RESUMEN

INTRODUCTION: A growing number of Americans search online for health information related to urologic oncologic care each year. The American Medical Association recommends that medical information be written at a maximum sixth-grade level in order to be comprehensible by the majority of patients. As such, it is important to assess the quality and readability of online patient education material that patients are being exposed to. METHODS: A Google search was performed using the terms "testicular cancer," "prostate cancer," "kidney cancer," and "bladder cancer," and the top 30 results for each were reviewed. Websites were categorized based on their source. Readability was assessed using the Flesch-Kincaid Grade Level, the Gunning Frequency of Gobbledygook, and the Simple Measure of Gobbledygook indices. Quality was assessed using the DISCERN Quality Index (1-5 scale). RESULTS: A total of 91 websites were included in our analysis. On average, online health information pertaining to urologic cancers is written at a 10th- to 11th-grade reading level, which is significantly higher than that of an average American adult and that recommended by the American Medical Association (P < .01). The overall quality of websites was 3.4 ± 0.7, representing moderate to high quality. There was no significant difference in readability based on cancer type or information source. CONCLUSIONS: Despite being of moderate to high quality, online patient education materials related to common urologic cancers are often written at a grade level that exceeds the reading level of an average American adult. This presents as a barrier to online health literacy and calls into question the utility of these resources.

Asunto(s)

Comprensión , Información de Salud al Consumidor , Alfabetización en Salud , Internet , Educación del Paciente como Asunto , Neoplasias Urológicas , Humanos , Educación del Paciente como Asunto/métodos , Información de Salud al Consumidor/normas , Masculino , Estados Unidos , Neoplasias de la Próstata , Oncología Médica

RESUMEN

Influenza A virus subtype H2N2, which caused the 1957 influenza pandemic, remains a global threat. A recent phase 1 clinical trial investigating a ferritin nanoparticle vaccine displaying H2 hemagglutinin (HA) in H2-naive and H2-exposed adults enabled us to perform comprehensive structural and biochemical characterization of immune memory on the breadth and diversity of the polyclonal serum antibody response elicited. We temporally map the epitopes targeted by serum antibodies after vaccine prime and boost, revealing that previous H2 exposure results in higher responses to the variable HA head domain. In contrast, initial responses in H2-naive participants are dominated by antibodies targeting conserved epitopes. We use cryoelectron microscopy and monoclonal B cell isolation to describe the molecular details of cross-reactive antibodies targeting conserved epitopes on the HA head, including the receptor-binding site and a new site of vulnerability deemed the medial junction. Our findings accentuate the impact of pre-existing influenza exposure on serum antibody responses post-vaccination.

Asunto(s)

Anticuerpos Antivirales , Memoria Inmunológica , Subtipo H2N2 del Virus de la Influenza A , Vacunas contra la Influenza , Vacunación , Humanos , Anticuerpos Antivirales/inmunología , Vacunas contra la Influenza/inmunología , Subtipo H2N2 del Virus de la Influenza A/inmunología , Gripe Humana/inmunología , Gripe Humana/prevención & control , Formación de Anticuerpos/inmunología , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Epítopos/inmunología , Adulto , Linfocitos B/inmunología

RESUMEN

Cancer-associated fibroblasts (CAF) are a prominent cell type within the tumor microenvironment (TME) where they are known to promote cancer cell growth and survival, angiogenesis, drug resistance, and immunosuppression. The transmembrane prolyl protease fibroblast activation protein (FAP) is expressed on the surface of highly protumorigenic CAFs found in the stroma of nearly every cancer of epithelial origin. The widespread expression of FAP has made it an attractive therapeutic target based on the underlying hypothesis that eliminating protumorigenic CAFs will disrupt the cross-talk between components of TME resulting in cancer cell death and immune infiltration. This hypothesis, however, has never been directly proven. To eliminate FAP-expressing CAFs, we developed an antibody-drug conjugate using our anti-FAP antibody, huB12, coupled to a monomethyl auristatin E (huB12-MMAE) payload. After determining that huB12 was an effective targeting vector, we found that huB12-MMAE potently eliminated FAP-expressing cells as monocultures in vitro and significantly prolonged survival in vivo using a xenograft engineered to overexpress FAP. We investigated the effects of selectively eliminating CAFs using a layered, open microfluidic cell coculture platform, known as the Stacks. Analysis of mRNA and protein expression found that treatment with huB12-MMAE resulted in the increased secretion of the proinflammatory cytokines IL6 and IL8 by CAFs and an associated increase in expression of proinflammatory genes in cancer cells. We also detected increased secretion of CSF1, a cytokine involved in myeloid recruitment and differentiation. Our findings suggest that the mechanism of FAP-targeted therapies is through effects on the immune microenvironment and antitumor immune response. SIGNIFICANCE: The direct elimination of FAP-expressing CAFs disrupts the cross-talk with cancer cells leading to a proinflammatory response and alterations in the immune microenvironment and antitumor immune response.

Asunto(s)

Fibroblastos Asociados al Cáncer , Endopeptidasas , Inmunoconjugados , Microambiente Tumoral , Humanos , Animales , Inmunoconjugados/farmacología , Fibroblastos Asociados al Cáncer/metabolismo , Fibroblastos Asociados al Cáncer/efectos de los fármacos , Fibroblastos Asociados al Cáncer/patología , Fibroblastos Asociados al Cáncer/inmunología , Ratones , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología , Endopeptidasas/genética , Endopeptidasas/metabolismo , Línea Celular Tumoral , Serina Endopeptidasas/metabolismo , Serina Endopeptidasas/genética , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Gelatinasas/metabolismo , Gelatinasas/genética , Oligopéptidos/farmacología , Femenino

RESUMEN

Germline-targeting (GT) HIV vaccine strategies are predicated on deriving broadly neutralizing antibodies (bnAbs) through multiple boost immunogens. However, as the recruitment of memory B cells (MBCs) to germinal centers (GCs) is inefficient and may be derailed by serum antibody-induced epitope masking, driving further B cell receptor (BCR) modification in GC-experienced B cells after boosting poses a challenge. Using humanized immunoglobulin knockin mice, we found that GT protein trimer immunogen N332-GT5 could prime inferred-germline precursors to the V3-glycan-targeted bnAb BG18 and that B cells primed by N332-GT5 were effectively boosted by either of two novel protein immunogens designed to have minimum cross-reactivity with the off-target V1-binding responses. The delivery of the prime and boost immunogens as messenger RNA lipid nanoparticles (mRNA-LNPs) generated long-lasting GCs, somatic hypermutation, and affinity maturation and may be an effective tool in HIV vaccine development.

Asunto(s)

Vacunas contra el SIDA , Anticuerpos ampliamente neutralizantes , Centro Germinal , Anticuerpos Anti-VIH , VIH-1 , Inmunización Secundaria , Nanopartículas , Vacunas de ARNm , Animales , Humanos , Ratones , Vacunas contra el SIDA/inmunología , Linfocitos B/inmunología , Anticuerpos ampliamente neutralizantes/inmunología , Reacciones Cruzadas , Técnicas de Sustitución del Gen , Centro Germinal/inmunología , Anticuerpos Anti-VIH/inmunología , Proteína gp120 de Envoltorio del VIH/inmunología , Proteína gp120 de Envoltorio del VIH/química , Proteína gp120 de Envoltorio del VIH/genética , Infecciones por VIH/inmunología , Infecciones por VIH/prevención & control , VIH-1/inmunología , VIH-1/genética , Liposomas , Células B de Memoria/inmunología , Receptores de Antígenos de Linfocitos B/inmunología , Receptores de Antígenos de Linfocitos B/genética , Hipermutación Somática de Inmunoglobulina , Vacunas de ARNm/inmunología , Femenino , Ratones Endogámicos C57BL

RESUMEN

OBJECTIVE: Malabsorption of levothyroxine (LT4) is often seen in patients with hypothyroidism and gastrointestinal (GI) conditions. Our study was designed to establish the prevalence of small intestinal bacterial overgrowth (SIBO) in patients with hypothyroidism and irritable bowel syndrome (IBS), and to demonstrate that liquid LT4 is more consistently absorbed vs tablet, leading to improvement in thyroid and GI symptoms. METHODS: This was a single-center, open label, prospective cohort study of liquid LT4 in 75 adult patients with hypothyroidism and IBS. Patients were transitioned from LT4 tablets to solution at equivalent dosing. Patients returned at 6 and 12 weeks for repeat thyroid levels and completion of validated questionnaires. A standard 2-hour SIBO breath test was administered at Week 6. Patients recorded daily stool appearance and frequency. RESULTS: Prevalence of SIBO was 65.3%. Liquid LT4 normalized thyroid stimulating hormone (TSH) in a higher percentage of patients vs tablet (77.55% vs 57.14%); significantly decreased TSH in subjects with SIBO; improved hypothyroid symptoms, IBS symptoms, stool appearance in all groups, and significantly altered bowel frequency among those with SIBO. CONCLUSION: Small intestinal bacterial overgrowth (SIBO) is common in patients with hypothyroidism and IBS. Among SIBO patients, LT4 tablets were inefficiently absorbed, leading to suboptimal thyroid control; however, transitioning from LT4 tablets to solution normalized TSH and improved hypothyroid symptoms. Liquid LT4 also significantly improved GI symptoms in all patients with hypothyroidism and IBS, regardless of SIBO status. Additionally, 1 in 5 patients had complete resolution of IBS symptoms after switching from LT4 tablets to solution, independent of changes in TSH.

Asunto(s)

Hipotiroidismo , Intestino Delgado , Síndrome del Colon Irritable , Tiroxina , Humanos , Hipotiroidismo/tratamiento farmacológico , Hipotiroidismo/sangre , Hipotiroidismo/epidemiología , Síndrome del Colon Irritable/tratamiento farmacológico , Síndrome del Colon Irritable/microbiología , Femenino , Persona de Mediana Edad , Masculino , Adulto , Tiroxina/uso terapéutico , Tiroxina/administración & dosificación , Intestino Delgado/microbiología , Estudios Prospectivos , Anciano , Resultado del Tratamiento , Síndrome del Asa Ciega/tratamiento farmacológico , Síndrome del Asa Ciega/epidemiología

RESUMEN

PURPOSE: The current standard of care for muscle invasive bladder cancer (MIBC) is neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC). Previous research has shown under-utilization of NAC for treatment of MIBC, especially among the elderly. Our aim was to stratify NAC use by decade of life and analyze trends in use over time along with recording pathologic downstaging and perioperative outcomes. MATERIALS AND METHODS: The National Cancer Database was queried for patients with cT2-4NanyM0 MIBC treated with RC from 2010 to 2016 with urothelial carcinoma. Nineteen thousand nine hundred fifty seven patients met criteria for analysis. We retrospectively analyzed trends in use of NAC, readmission rate, mortality rate, and pathologic downstaging with NAC all stratified by decade of life. RESULTS: Of the 19,957 patients treated with RC for MIBC, only 30.9% underwent NAC. There was a statistically significant increase in NAC use across all age groups from 2010 to 2016. Receipt of NAC was associated with decreased age on univariate analysis (P < 0.001) and on logistic regression (OR: 0.617 for age 70-79, OR: 0.221 for age ≥80 vs. age <60; P < 0.001). Patients receiving NAC were more likely to exhibit pathologic downstaging at time of RC (OR: 3.907; P < 0.001), and this trend held for each age group examined. Among patients receiving NAC, the risk of 30 and 90-day mortality was associated with increasing age; however, age was not associated with 30-day readmission for those receiving NAC. CONCLUSION: Rates of NAC use prior to RC have increased among all age groups with the lowest utilization rate among the elderly. NAC use was associated with greater pathologic downstaging in all age groups. These data show a promising trend in the uptake of the gold standard for treatment of MIBC; however, the underlying etiology of differing rates of NAC utilization remains to be determined.

Asunto(s)

Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Humanos , Anciano , Neoplasias de la Vejiga Urinaria/patología , Carcinoma de Células Transicionales/tratamiento farmacológico , Carcinoma de Células Transicionales/cirugía , Carcinoma de Células Transicionales/etiología , Terapia Neoadyuvante , Estudios Retrospectivos , Cistectomía , Músculos/patología , Quimioterapia Adyuvante , Invasividad Neoplásica

RESUMEN

Influenza A virus subtype H2N2, which caused the 1957 influenza pandemic, remains a global threat. A recent phase I clinical trial investigating a ferritin nanoparticle displaying H2 hemagglutinin in H2-naïve and H2-exposed adults. Therefore, we could perform comprehensive structural and biochemical characterization of immune memory on the breadth and diversity of the polyclonal serum antibody response elicited after H2 vaccination. We temporally map the epitopes targeted by serum antibodies after first and second vaccinations and show previous H2 exposure results in higher responses to the variable head domain of hemagglutinin while initial responses in H2-naïve participants are dominated by antibodies targeting conserved epitopes. We use cryo-EM and monoclonal B cell isolation to describe the molecular details of cross-reactive antibodies targeting conserved epitopes on the hemagglutinin head including the receptor binding site and a new site of vulnerability deemed the medial junction. Our findings accentuate the impact of pre-existing influenza exposure on serum antibody responses.

RESUMEN

Cows produce antibodies with a disulfide-bonded antigen-binding domain embedded within ultralong heavy chain third complementarity determining regions. This "knob" domain is analogous to natural cysteine-rich peptides such as knottins in that it is small and stable but can accommodate diverse loops and disulfide bonding patterns. We immunized cattle with SARS-CoV-2 spike and found ultralong CDR H3 antibodies that could neutralize several viral variants at picomolar IC50 potencies in vitro and could protect from disease in vivo. The independent CDR H3 peptide knobs were expressed and maintained the properties of the parent antibodies. The knob interaction with SARS-CoV-2 spike was revealed by electron microscopy, X-ray crystallography, NMR spectroscopy, and mass spectrometry and established ultralong CDR H3-derived knobs as the smallest known recombinant independent antigen-binding fragment. Unlike other vertebrate antibody fragments, these knobs are not reliant on the immunoglobulin domain and have potential as a new class of therapeutics.

Asunto(s)

COVID-19 , SARS-CoV-2 , Femenino , Animales , Bovinos , Anticuerpos , Fragmentos Fab de Inmunoglobulinas/genética , Disulfuros

RESUMEN

Understanding antibody-antigen interactions in a polyclonal immune response in humans and animal models is critical for rational vaccine design. Current approaches typically characterize antibodies that are functionally relevant or highly abundant. Here, we use photo-cross-linking and single-particle electron microscopy to increase antibody detection and unveil epitopes of low-affinity and low-abundance antibodies, leading to a broader structural characterization of polyclonal immune responses. We employed this approach across three different viral glycoproteins and showed increased sensitivity of detection relative to currently used methods. Results were most noticeable in early and late time points of a polyclonal immune response. Additionally, the use of photo-cross-linking revealed intermediate antibody binding states and demonstrated a distinctive way to study antibody binding mechanisms. This technique can be used to structurally characterize the landscape of a polyclonal immune response of patients in vaccination or post-infection studies at early time points, allowing for rapid iterative design of vaccine immunogens.

Asunto(s)

Anticuerpos Neutralizantes , Vacunas , Animales , Humanos , Epítopos/química , Vacunación

RESUMEN

Electron microscopy-based polyclonal epitope mapping (EMPEM) can delineate epitope specificities of serum antibodies to a given antigen following vaccination or infection. Here, we present a protocol for the EMPEM method for rapid high-throughput assessment of antibody responses to glycoprotein antigens in vaccination and infection studies. We describe steps for antibody isolation and digestion, antigen complex and purification, and electron microscope imaging. We then detail procedures for processing and analysis of EMPEM data. For complete details on the use and execution of this protocol, please refer to Bianchi et al. (2018).1.

Asunto(s)

Formación de Anticuerpos , Electrones , Mapeo Epitopo , Microscopía Electrónica , Anticuerpos , Glicoproteínas

RESUMEN

Melanocortin 3 receptors (MC3R) and melanocortin 4 receptors (MC4R) are vital in regulating a variety of functions across many species. For example, the dysregulation of these receptors results in obesity and dysfunction in sexual behaviors. Only a handful of studies have mapped the expression of MC3R and MC4R mRNA across the central nervous system, with the primary focus on mice and rats. Because Syrian hamsters are valuable models for functions regulated by melanocortin receptors, our current study maps the distribution of MC3R and MC4R mRNA in the Syrian hamster telencephalon, diencephalon, and midbrain using RNAscope. We found that the expression of MC3R mRNA was lowest in the telencephalon and greatest in the diencephalon, whereas the expression of MC4R mRNA was greatest in the midbrain. A comparison of these findings to previous studies found that MC3R and MC4R expression is similar in some brain regions across species and divergent in others. In addition, our study identifies novel brain regions for the expression of MC3Rs and MC4Rs, and identifies cells that co-express bothMC3 and MC4 receptors within certain brain regions.

RESUMEN

Like many social behaviors, aggression can be rewarding, leading to behavioral plasticity. One outcome of reward-induced aggression is the long-term increase in the speed in which future aggression-based encounters is initiated. This form of aggression impacts dendritic structure and excitatory synaptic neurotransmission in the nucleus accumbens, a brain region well known to regulate motivated behaviors. Yet, little is known about the intracellular signaling mechanisms that drive these structural/functional changes and long-term changes in aggressive behavior. This study set out to further elucidate the intracellular signaling mechanisms regulating the plasticity in neurophysiology and behavior that underlie the rewarding consequences of aggressive interactions. Female Syrian hamsters experienced zero, two or five aggressive interactions and the phosphorylation of proteins in reward-associated regions was analyzed. We report that aggressive interactions result in a transient increase in the phosphorylation of extracellular-signal related kinase 1/2 (ERK1/2) in the nucleus accumbens. We also report that aggressive interactions result in a transient decrease in the phosphorylation of mammalian target of rapamycin (mTOR) in the medial prefrontal cortex, a major input structure to the nucleus accumbens. Thus, this study identifies ERK1/2 and mTOR as potential signaling pathways for regulating the long-term rewarding consequences of aggressive interactions. Furthermore, the recruitment profile of the ERK1/2 and the mTOR pathways are distinct in different brain regions.

Asunto(s)

Sistema de Señalización de MAP Quinasas , Núcleo Accumbens , Cricetinae , Animales , Femenino , Núcleo Accumbens/metabolismo , Mesocricetus , Fosforilación , Agresión/fisiología , Corteza Prefrontal/metabolismo , Serina-Treonina Quinasas TOR/metabolismo

RESUMEN

BACKGROUND: E-liquid flavour restrictions may discourage electronic cigarette (e-cigarette) uptake among youth. However, possible unintended consequences may include reduced appeal and effectiveness of e-cigarettes for smoking cessation. Non-tobacco flavours appear to be important for smoking cessation, but how and why are currently unclear. METHODS: We conducted an experimental study in a UK sample of adult daily smokers using an independent groups design (N=84). Participants were randomised to use an e-cigarette with nicotine-containing fruit/sweet-flavoured e-liquid (blackcurrant, strawberry, vanilla, caramel) or unflavoured e-liquid for 1 week. The primary outcomes were average, peak and cue-elicited cigarette craving (the latter was assessed using a cue exposure task). The secondary outcomes were smoking lapse occurrence, enjoyment of the e-cigarette, ease of transitioning from smoking to using an e-cigarette, intentions to continue using an e-cigarette, intentions and motivation to quit smoking, return to smoking, and continuation of e-cigarette use. RESULTS: E-liquid flavouring did not appear to have an effect on average cigarette craving (b 0.18, 95% CI -0.44 to 0.79, p=0.57), peak cigarette craving (b -0.12, 95% CI -0.59 to 0.35, p=0.62) or cue-elicited cigarette craving (b -0.21, 95% CI -3.86 to 3.43, p=0.91). We did not find evidence of a difference in secondary outcomes. CONCLUSIONS: We did not find evidence to suggest that nicotine-containing fruit/sweet-flavoured and unflavoured e-liquids have different effects on cigarette cravings after 1 week of use. Further research is needed to establish if differences emerge over longer periods of exposure and extend to smoking cessation outcomes.

Asunto(s)

Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Adulto , Adolescente , Humanos , Nicotina/farmacología , Ansia , Fumar , Aromatizantes

RESUMEN

MODY3 is a monogenic hereditary form of diabetes caused by mutations in the transcription factor HNF1A. The patients progressively develop hyperglycemia due to perturbed insulin secretion, but the pathogenesis is unknown. Using patient-specific hiPSCs, we recapitulate the insulin secretion sensitivity to the membrane depolarizing agent sulfonylurea commonly observed in MODY3 patients. Unexpectedly, MODY3 patient-specific HNF1A+/R272C ß cells hypersecrete insulin both in vitro and in vivo after transplantation into mice. Consistently, we identified a trend of increased birth weight in human HNF1A mutation carriers compared with healthy siblings. Reduced expression of potassium channels, specifically the KATP channel, in MODY3 ß cells, increased calcium signaling, and rescue of the insulin hypersecretion phenotype by pharmacological targeting ATP-sensitive potassium channels or low-voltage-activated calcium channels suggest that more efficient membrane depolarization underlies the hypersecretion of insulin in MODY3 ß cells. Our findings identify a pathogenic mechanism leading to ß cell failure in MODY3.

Asunto(s)

Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Humanos , Ratones , Animales , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Diabetes Mellitus Tipo 2/genética , Fenotipo

RESUMEN

We present a rare case of a solitary intracranial plasmacytoma of the brain parenchyma in a 49-year-old female who presented with neck pain/headache, paresthesias, and auditory hallucinations. A workup revealed a solitary left parietal lobe brain lesion and a biopsy demonstrated a plasma cell infiltrate consistent with an extramedullary plasmacytoma. A complete workup for multiple myeloma was negative. As opposed to surgical resection and adjuvant radiation therapy (RT), as described in prior case reports in the literature, this patient was managed with definitive local RT alone to 50 Gy in 25 fractions. Six months following primary RT completion, the patient's presenting symptoms completely resolved and follow-up imaging revealed regression of the primary tumor. To our knowledge, this is the first reported case of a solitary extramedullary plasmacytoma of the brain treated with localized definitive RT alone.

RESUMEN

In the cold deserts of the McMurdo Dry Valleys (MDV) the suitability of soil for microbial life is determined by both contemporary processes and legacy effects. Climatic changes and accompanying glacial activity have caused local extinctions and lasting geochemical changes to parts of these soil ecosystems over several million years, while areas of refugia may have escaped these disturbances and existed under relatively stable conditions. This study describes the impact of historical glacial and lacustrine disturbance events on microbial communities across the MDV to investigate how this divergent disturbance history influenced the structuring of microbial communities across this otherwise very stable ecosystem. Soil bacterial communities from 17 sites representing either putative refugia or sites disturbed during the Last Glacial Maximum (LGM) (22-17 kya) were characterized using 16 S metabarcoding. Regardless of geographic distance, several putative refugia sites at elevations above 600 m displayed highly similar microbial communities. At a regional scale, community composition was found to be influenced by elevation and geographic proximity more so than soil geochemical properties. These results suggest that despite the extreme conditions, diverse microbial communities exist in these putative refugia that have presumably remained undisturbed at least through the LGM. We suggest that similarities in microbial communities can be interpreted as evidence for historical climate legacies on an ecosystem-wide scale.