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1.
Cell ; 186(3): 577-590.e16, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36693373

RESUMO

Pleasurable touch is paramount during social behavior, including sexual encounters. However, the identity and precise role of sensory neurons that transduce sexual touch remain unknown. A population of sensory neurons labeled by developmental expression of the G protein-coupled receptor Mrgprb4 detects mechanical stimulation in mice. Here, we study the social relevance of Mrgprb4-lineage neurons and reveal that these neurons are required for sexual receptivity and sufficient to induce dopamine release in the brain. Even in social isolation, optogenetic stimulation of Mrgprb4-lineage neurons through the back skin is sufficient to induce a conditioned place preference and a striking dorsiflexion resembling the lordotic copulatory posture. In the absence of Mrgprb4-lineage neurons, female mice no longer find male mounts rewarding: sexual receptivity is supplanted by aggression and a coincident decline in dopamine release in the nucleus accumbens. Together, these findings establish that Mrgprb4-lineage neurons initiate a skin-to-brain circuit encoding the rewarding quality of social touch.


Assuntos
Dopamina , Tato , Camundongos , Masculino , Feminino , Animais , Dopamina/metabolismo , Núcleo Accumbens/metabolismo , Células Receptoras Sensoriais/metabolismo , Pele/metabolismo , Recompensa , Neurônios Dopaminérgicos/metabolismo , Optogenética , Receptores Acoplados a Proteínas G/metabolismo
2.
Nat Immunol ; 24(7): 1124-1137, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37217705

RESUMO

The magnitude and quality of the germinal center (GC) response decline with age, resulting in poor vaccine-induced immunity in older individuals. A functional GC requires the co-ordination of multiple cell types across time and space, in particular across its two functionally distinct compartments: the light and dark zones. In aged mice, there is CXCR4-mediated mislocalization of T follicular helper (TFH) cells to the dark zone and a compressed network of follicular dendritic cells (FDCs) in the light zone. Here we show that TFH cell localization is critical for the quality of the antibody response and for the expansion of the FDC network upon immunization. The smaller GC and compressed FDC network in aged mice were corrected by provision of TFH cells that colocalize with FDCs using CXCR5. This demonstrates that the age-dependent defects in the GC response are reversible and shows that TFH cells support stromal cell responses to vaccines.


Assuntos
Linfócitos T Auxiliares-Indutores , Vacinas , Animais , Camundongos , Linfócitos B , Células T Auxiliares Foliculares , Centro Germinativo , Envelhecimento
3.
Am Nat ; 202(5): 655-666, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37963121

RESUMO

AbstractHosts and brood parasites are a classic example of conflict. Parasites typically provide no offspring care after laying eggs, imposing costs on hosts. Female subsocial wasps (Ammophila pubescens) alternate between initiating their own nests and using an "intruder" tactic of replacing eggs in nests of unrelated conspecifics. Hosts can respond by substituting new eggs of their own, with up to eight reciprocal replacements. Remarkably, intruders usually provision offspring in host nests, often alongside hosts. We used field data to investigate why intruders provision and to understand the basis of interactions. We found that intruders could not increase their fitness payoffs by using the typical brood parasite tactic of not provisioning offspring. Intruders using the typical tactic would benefit when hosts provisioned in their stead, but their offspring would starve when hosts failed to provision. Although some hosts obtained positive payoffs when intruders mistakenly provisioned their offspring, on average utilizing a conspecific nest represents parasitism: hosts pay costs while intruders benefit. Hosts and intruders used the same tactic of egg replacement, but intruders more often laid the final egg. Selection should favor better discrimination of offspring, which could lead to repeated cycles of costly egg replacement.


Assuntos
Parasitos , Vespas , Animais , Feminino , Comportamento de Nidação , Interações Hospedeiro-Parasita
4.
Immunol Cell Biol ; 101(6): 479-488, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36975169

RESUMO

Effective vaccines have reduced the morbidity and mortality caused by severe acute respiratory syndrome coronavirus-2 infection; however, the elderly remain the most at risk. Understanding how vaccines generate protective immunity and how these mechanisms change with age is key for informing future vaccine design. Cytotoxic CD8+ T cells are important for killing virally infected cells, and vaccines that induce antigen-specific CD8+ T cells in addition to humoral immunity provide an extra layer of immune protection. This is particularly important in cases where antibody titers are suboptimal, as can occur in older individuals. Here, we show that in aged mice, spike epitope-specific CD8+ T cells are generated in comparable numbers to younger animals after ChAdOx1 nCoV-19 vaccination, although phenotypic differences exist. This demonstrates that ChAdOx1 nCoV-19 elicits a good CD8+ T-cell response in older bodies, but that typical age-associated features are evident on these vaccine reactive T cells.


Assuntos
Linfócitos T CD8-Positivos , COVID-19 , Animais , Humanos , Camundongos , ChAdOx1 nCoV-19 , COVID-19/prevenção & controle , Vacinação , Linfócitos T Citotóxicos , Anticorpos Antivirais
5.
Horm Behav ; 149: 105312, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36645923

RESUMO

In placental mammals, estradiol levels are chronically elevated during pregnancy, but quickly drop to prepartum levels following birth. This may produce an "estrogen withdrawal" state that has been linked to changes in affective states in humans and rodents during the postpartum period. The neural mechanisms underlying these affective changes, however, are understudied. We used a hormone-simulated pseudopregnancy (HSP), a model of postpartum estrogen withdrawal, in adult female C57BL/6 mice to test the impact of postpartum estradiol withdrawal on several behavioral measures of anxiety and motivation. We found that estradiol withdrawal following HSP increased anxiety-like behavior in the elevated plus maze, but not in the open field or marble burying tests. Although hormone treatment during HSP consistently increased sucrose consumption, sucrose preference was generally not impacted by hormone treatment or subsequent estradiol withdrawal. In the social motivation test, estradiol withdrawal decreased the amount of time spent in proximity to a social stimulus animal. These behavioral changes were accompanied by changes in the expression of ∆FosB, a transcription factor correlated with stable long-term plasticity, in the nucleus accumbens (NAc). Specifically, estrogen-withdrawn females had higher ∆FosB expression in the nucleus accumbens core, but ∆FosB expression did not vary across hormone conditions in the nucleus accumbens shell. Using transgenic reporter mice, we found that this increase in ∆FosB occurred in both D1- and D2-expressing cells in the NAc core. Together, these results suggest that postpartum estrogen withdrawal impacts anxiety and motivation and increases ∆FosB in the NAc core.


Assuntos
Estradiol , Núcleo Accumbens , Animais , Feminino , Camundongos , Gravidez , Estradiol/farmacologia , Estrogênios/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/metabolismo , Núcleo Accumbens/metabolismo , Placenta/metabolismo , Receptores de Dopamina D1/metabolismo , Sacarose
6.
J Urol ; 207(5): 1020-1028, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34978211

RESUMO

PURPOSE: Cardiovascular disease is a common cause of death in prostate cancer patients. Low testosterone is associated with increased cardiovascular risk in the general male population. We investigated the relationship between serum testosterone, cardiovascular disease and risk factors in androgen-deprivation therapy-naïve prostate cancer patients. MATERIALS AND METHODS: We performed a cross-sectional analysis of a subgroup of 1,326 androgen-deprivation therapy-naïve men from RADICAL-PC (Role of Androgen-Deprivation Therapy In CArdiovascular Disease-A Longitudinal Prostate Cancer study) in whom serum testosterone was measured at baseline. RADICAL-PC is a prospective multicenter cohort study of men (2,565) enrolled within 1 year of prostate cancer diagnosis, or within 6 months of commencing androgen-deprivation therapy for the first time. Cardiovascular risk factors, cancer characteristics and total serum testosterone were collected at baseline. Low testosterone was defined as total serum testosterone <11 nmol/L (<320 ng/dL). A Framingham cardiovascular risk score ≥15 was considered high risk for future cardiovascular events. We performed logistic regression to calculate odds ratios for the association between testosterone and cardiovascular risk. RESULTS: Among 1,326 participants (median age 67 years, range 45-93), 553 (42%) had low testosterone. Low testosterone was associated with existing cardiovascular disease, diabetes, elevated hemoglobin A1c, obesity, hypertriglyceridemia, low high-density lipoprotein cholesterol, hypertension and Framingham score >15. Among patients with low testosterone, the odds ratio for high cardiovascular risk was 1.33 (1.02-1.73) after adjusting for ethnicity, education, alcohol use, cancer characteristics, physical activity and body mass index. CONCLUSIONS: Among androgen-deprivation therapy-naïve prostate cancer patients, low testosterone is common and associated with increased cardiovascular risk factors.


Assuntos
Doenças Cardiovasculares , Neoplasias da Próstata , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/efeitos adversos , Androgênios , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/etiologia , Estudos de Coortes , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Testosterona
7.
J Proteome Res ; 19(4): 1592-1619, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32050077

RESUMO

Pain and emotional distress have a reciprocal relation. The amygdala has been implicated in emotional processing. The central nucleus of the amygdala (CeA) receives nociceptive information from the dorsal horn of spinal cord and is responsible for the central plasticity in chronic pain. Neuropathic pain is a type of severe chronic pain and can be strongly influenced by emotional components. Plastic changes in the CeA may play a key role in the development or maintenance or both of neuropathic pain. We studied the expression levels of proteins in the CeA of spinal nerve transection (SNT) model rats. Total tissue lysate proteins were separated by two-dimensional-gel electrophoresis (2D-PAGE). Gels from different time points were compared using Progenesis SameSpot software, and the spots with Fold Change greater than 2 were excised for protein identification by mass spectrometry. We identified more than 50 cytosolic proteins as significantly altered in their expression levels in the CeA of SNT rats, and most of these changes have been validated at mRNA levels by qRT-PCR. We also identified more than 40 membrane proteins as notably up- or down-regulated in the CeA of SNT model rats relative to a control using stable isotope dimethyl labeling nano-LC-MS/MS based proteomics and found that one such protein, doublecortin (DCX), a microtubule-associated protein expressed by neuronal precursor cells during development, is specifically localized in the membrane fraction without changes in total amount of the protein. Immunohistochemistry showed that doublecortin is expressed in processes in the CeA of rats 7 and 21 days after SNT surgery, suggesting that doublecortin is one of the proteins that may contribute to the plastic changes, namely, redevelopment or rewiring of neural networks, in the CeA in the neuropathic pain model. These dysregulated proteins may play roles in reciprocal relationships between pain and psychological distress in the amygdala and contribute to central sensitization. Data are available via ProteomeXchange with identifier PXD017473.


Assuntos
Núcleo Central da Amígdala , Neuralgia , Animais , Proteína Duplacortina , Proteômica , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
8.
Prostate ; 80(8): 632-639, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32201973

RESUMO

BACKGROUND: Radiotherapy and brachytherapy are common treatments for localized prostate cancer (PCa). However, very few studies evaluated the association of variations in DNA damage response genes and treatment outcomes and toxicity in brachytherapy-treated patients. PURPOSE: To evaluate the association of inherited germline variations in DNA repair-associated genes with tumor control and treatment toxicity in patients treated with low-dose-rate prostate brachytherapy (LDRB). MATERIAL AND METHODS: The cohort consists of 475 I-125 LDRB patients with a median follow-up of 51 months after seed implantation. Patients were genotyped for 215 haplotype tagging single nucleotide variations (htSNPs) in 29 candidate genes of DNA damage response and repair pathways. Their association with biochemical recurrence (BCR) was assessed using Cox regression models and Kaplan-Meier survival curves. Linear regressions and analysis of covariance (ANCOVA) between early and late International Prostate Symptom Score (IPSS) with htSNPs were used to evaluate the association with urinary toxicity. RESULTS: After adjustment for the established risk factors, six htSNPs in five genes were found to be significantly associated with an altered risk of BCR, with adjusted hazard ratios (HRadj. ) ranging between 3.6 and 11.1 (P < .05). Compared to carriers of the ERCC3 rs4150499C allele, patients homozygous for the T allele (n = 22) had a significant higher risk of BCR with a HR of 11.13 (IC95 = 3.9-32.0; P < .0001; q < 0.001). The Kaplan-Meier survival curve revealed a mean BCR-free survival time reduced from 213 ± 7 to 99 ± 12 months (log-rank P < .0001) for homozygous T carriers compare to noncarriers. For late IPSS (>6 months after treatment), htSNP rs6544990 from MSH2 showed a statistically significant b-coefficient of 1.85 ± 0.52 (P < .001; q < 0.1). Homozygous carriers of the MSH2 rs6544990C allele (n = 62) had a mean late IPSS 3.6 points higher than patients homozygous for the A allele (n = 132). This difference was significant when tested by ANCOVA using pretreatment IPSS as a covariate (P < .01). CONCLUSIONS: This study suggests an association of the intronic variants of the DNA nucleotide excision repair ERCC3 and DNA mismatch repair MSH2 genes with elevated risk of BCR and late urinary toxicity respectively after LDRB. Further validation is required before translational clinical advances.


Assuntos
Braquiterapia/efeitos adversos , Braquiterapia/métodos , Reparo do DNA/genética , Radioisótopos do Iodo/administração & dosagem , Neoplasias da Próstata/genética , Neoplasias da Próstata/radioterapia , Mutação em Linhagem Germinativa , Humanos , Radioisótopos do Iodo/efeitos adversos , Masculino , Doenças Urogenitais Masculinas/etiologia , Doenças Urogenitais Masculinas/genética , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Lesões por Radiação/etiologia , Lesões por Radiação/genética
9.
Proc Biol Sci ; 285(1889)2018 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-30355705

RESUMO

The Late Triassic and Early Toarcian extinction events are both associated with greenhouse warming events triggered by massive volcanism. These Mesozoic hyperthermals were responsible for the mass extinction of marine organisms and resulted in significant ecological upheaval. It has, however, been suggested that these events merely involved intensification of background extinction rates rather than significant shifts in the macroevolutionary regime and extinction selectivity. Here, we apply a multivariate modelling approach to a vast global database of marine organisms to test whether extinction selectivity varied through the Late Triassic and Early Jurassic. We show that these hyperthermals do represent shifts in the macroevolutionary regime and record different extinction selectivity compared to background intervals of the Late Triassic and Early Jurassic. The Late Triassic mass extinction represents a more profound change in selectivity than the Early Toarcian extinction but both events show a common pattern of selecting against pelagic predators and benthic photosymbiotic and suspension-feeding organisms, suggesting that these groups of organisms may be particularly vulnerable during episodes of global warming. In particular, the Late Triassic extinction represents a macroevolutionary regime change that is characterized by (i) the change in extinction selectivity between Triassic background intervals and the extinction event itself; and (ii) the differences in extinction selectivity between the Late Triassic and Early Jurassic as a whole.


Assuntos
Organismos Aquáticos , Evolução Biológica , Mudança Climática , Extinção Biológica , Temperatura Alta , Fósseis , Modelos Biológicos , Paleontologia
10.
Bioorg Med Chem Lett ; 28(2): 85-93, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29233651

RESUMO

We disclose the optimization of a high throughput screening hit to yield benzothiazine and tetrahydroquinoline sulfonamides as potent RORγt inverse agonists. However, a majority of these compounds showed potent activity against pregnane X receptor (PXR) and modest activity against liver X receptor α (LXRα). Structure-based drug design (SBDD) led to the identification of benzothiazine and tetrahydroquinoline sulfonamide analogs which completely dialed out LXRα activity and were less potent at PXR. Pharmacodynamic (PD) data for compound 35 in an IL-23 induced IL-17 mouse model is discussed along with the implications of a high Ymax in the PXR assay for long term preclinical pharmacokinetic (PK) studies.


Assuntos
Compostos Bicíclicos com Pontes/farmacologia , Desenho de Fármacos , Propanóis/farmacologia , Receptores do Ácido Retinoico/agonistas , Receptores de Esteroides/agonistas , Sulfonamidas/farmacologia , Animais , Compostos Bicíclicos com Pontes/síntese química , Compostos Bicíclicos com Pontes/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Humanos , Receptores X do Fígado/agonistas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Estrutura Molecular , Receptor de Pregnano X , Propanóis/síntese química , Propanóis/química , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Receptor gama de Ácido Retinoico
11.
BMC Ophthalmol ; 18(1): 29, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29402259

RESUMO

CORRECTION: After publication of the article [1], it has been brought to our attention that the images displayed in Figs. 1, 2 and 3 have been transposed.

12.
BMC Ophthalmol ; 18(1): 11, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29351793

RESUMO

BACKGROUND: There have been few reported findings of posterior segment complications of gout. While exudative lesions, an increased risk of macular degeneration, and vascular occlusions have been previously reported, to our knowledge, refractile macular lesions have not been reported in a patient with chronic uncontrolled gout. CASE PRESENTATION: Highly refractile, crystal-like lesions were found in the macula of a 62 year old male patient with chronically uncontrolled gout. The lesions appeared at the termination of retinal arterioles and were located at the level of the retinal pigment epithelium. The lesions did not stain with fluorescein and were associated with larger areas geographic atrophy. Review of the patient's blood tests revealed well-controlled vasculopathic risk factors. Fundus appearance and best-corrected visual acuity remained stable over 12 months of follow-up during which the uric acid levels were well controlled. CONCLUSION: Retinopathy may be associated with chronically uncontrolled gout and patients with visual complaints should undergo a dilated examination in addition to the typical anterior segment slit-lamp exam.


Assuntos
Segmento Anterior do Olho/diagnóstico por imagem , Gota/complicações , Macula Lutea/diagnóstico por imagem , Doenças Retinianas/etiologia , Vasos Retinianos/diagnóstico por imagem , Angiofluoresceinografia/métodos , Fundo de Olho , Gota/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Retinianas/diagnóstico , Tomografia de Coerência Óptica/métodos , Ácido Úrico/sangue , Acuidade Visual
13.
J Mol Cell Cardiol ; 105: 38-48, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28257760

RESUMO

The transformation of vascular smooth muscle cells [VSMC] into foam cells leading to increased plaque size and decreased stability is a key, yet understudied step in atherogenesis. We reported that Interleukin-19 (IL-19), a novel, anti-inflammatory cytokine, attenuates atherosclerosis by anti-inflammatory effects on VSMC. In this work we report that IL-19 induces expression of miR133a, a muscle-specific miRNA, in VSMC. Although previously unreported, we report that miR133a can target and reduce mRNA abundance, mRNA stability, and protein expression of Low Density Lipoprotein Receptor Adaptor Protein 1, (LDLRAP1), an adaptor protein which functions to internalize the LDL receptor. Mutations in this gene lead to LDL receptor malfunction and cause the Autosomal Recessive Hypercholesterolemia (ARH) disorder in humans. Herein we show that IL-19 reduces lipid accumulation in VSMC, and LDLRAP1 expression and oxLDL uptake in a miR133a-dependent mechanism. We show that LDLRAP1 is expressed in plaque and neointimal VSMC of mouse and human injured arteries. Transfection of miR133a and LDLRAP1 siRNA into VSMC reduces their proliferation and uptake of oxLDL. miR133a is significantly increased in plasma from hyperlipidemic compared with normolipidemic patients. Expression of miR133a in IL-19 stimulated VSMC represents a previously unrecognized link between vascular lipid metabolism and inflammation, and may represent a therapeutic opportunity to combat vascular inflammatory diseases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Células Endoteliais/metabolismo , Interleucinas/metabolismo , Lipoproteínas LDL/metabolismo , MicroRNAs/genética , Miócitos de Músculo Liso/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Linhagem Celular , Proliferação de Células , Células Cultivadas , Colesterol/metabolismo , Regulação da Expressão Gênica , Humanos , Hiperlipidemias/genética , Hiperlipidemias/metabolismo , Camundongos , Interferência de RNA , RNA Mensageiro/genética
14.
Environ Sci Technol ; 51(1): 560-569, 2017 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-27785914

RESUMO

Traditional cooking using biomass is associated with ill health, local environmental degradation, and regional climate change. Clean stoves (liquefied petroleum gas (LPG), biogas, and electric) are heralded as a solution, but few studies have demonstrated their environmental health benefits in field settings. We analyzed the impact of mainly biogas (as well as electric and LPG) stove use on social, environmental, and health outcomes in two districts in Odisha, India, where the Indian government has promoted household biogas. We established a cross-sectional observational cohort of 105 households that use either traditional mud stoves or improved cookstoves (ICS). Our multidisciplinary team conducted surveys, environmental air sampling, fuel weighing, and health measurements. We examined associations between traditional or improved stove use and primary outcomes, stratifying households by proximity to major industrial plants. ICS use was associated with 91% reduced use of firewood (p < 0.01), substantial time savings for primary cooks, a 72% reduction in PM2.5, a 78% reduction in PAH levels, and significant reductions in water-soluble organic carbon and nitrogen (p < 0.01) in household air samples. ICS use was associated with reduced time in the hospital with acute respiratory infection and reduced diastolic blood pressure but not with other health measurements. We find many significant gains from promoting rural biogas stoves in a context in which traditional stove use persists, although pollution levels in ICS households still remained above WHO guidelines.


Assuntos
Poluição do Ar em Ambientes Fechados , Biocombustíveis , Poluição do Ar , Mudança Climática , Culinária , Estudos Transversais , Humanos , Índia
15.
Nature ; 471(7339): E1-4; author reply E9-10, 2011 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-21430721

RESUMO

Arising from M. A. Nowak, C. E. Tarnita & E. O. Wilson 466, 1057-1062 (2010); Nowak et al. reply. Nowak et al. argue that inclusive fitness theory has been of little value in explaining the natural world, and that it has led to negligible progress in explaining the evolution of eusociality. However, we believe that their arguments are based upon a misunderstanding of evolutionary theory and a misrepresentation of the empirical literature. We will focus our comments on three general issues.


Assuntos
Altruísmo , Evolução Biológica , Aptidão Genética , Modelos Biológicos , Seleção Genética , Animais , Comportamento Cooperativo , Feminino , Teoria dos Jogos , Genética Populacional , Hereditariedade , Humanos , Masculino , Fenótipo , Reprodutibilidade dos Testes , Razão de Masculinidade
16.
Circulation ; 129(21): 2125-35, 2014 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-24657995

RESUMO

BACKGROUND: Pulmonary arterial hypertension (PAH) is a lethal disease characterized by excessive proliferation of pulmonary vascular endothelial cells (ECs). Hereditary PAH (HPAH) is often caused by mutations in the bone morphogenetic protein receptor type 2 gene (BMPR2). However, the mechanisms by which these mutations cause PAH remain unclear. Therefore, we screened for dysregulated proteins in blood-outgrowth ECs of HPAH patients with BMPR2 mutations compared with healthy control subjects. METHODS AND RESULTS: A total of 416 proteins were detected with 2-dimensional PAGE in combination with liquid chromatography/tandem mass spectrometry analysis, of which 22 exhibited significantly altered abundance in blood-outgrowth ECs from patients with HPAH. One of these proteins, translationally controlled tumor protein (TCTP), was selected for further study because of its well-established role in promoting tumor cell growth and survival. Immunostaining showed marked upregulation of TCTP in lungs from patients with HPAH and idiopathic PAH, associated with remodeled vessels of complex lesions. Increased TCTP expression was also evident in the SU5416 rat model of severe and irreversible PAH, associated with intimal lesions, colocalizing with proliferating ECs and the adventitia of remodeled vessels but not in the vascular media. Furthermore, silencing of TCTP expression increased apoptosis and abrogated the hyperproliferative phenotype of blood-outgrowth ECs from patients with HPAH, raising the possibility that TCTP may be a link in the emergence of apoptosis-resistant, hyperproliferative vascular cells after EC apoptosis. CONCLUSION: Proteomic screening identified TCTP as a novel mediator of endothelial prosurvival and growth signaling in PAH, possibly contributing to occlusive pulmonary vascular remodeling triggered by EC apoptosis.


Assuntos
Biomarcadores Tumorais/fisiologia , Células Endoteliais/patologia , Células Endoteliais/fisiologia , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/genética , Proteômica/métodos , Adulto , Idoso , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Hipertensão Pulmonar Primária Familiar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Ratos , Ratos Sprague-Dawley , Sobrevida/fisiologia , Proteína Tumoral 1 Controlada por Tradução , Adulto Jovem
17.
Ecol Lett ; 18(3): 254-62, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25622647

RESUMO

Understanding how species assemble into communities is a key goal in ecology. However, assembly rules are rarely tested experimentally, and their ability to shape real communities is poorly known. We surveyed a diverse community of epiphyte-dwelling ants and found that similar-sized species co-occurred less often than expected. Laboratory experiments demonstrated that invasion was discouraged by the presence of similarly sized resident species. The size difference for which invasion was less likely was the same as that for which wild species exhibited reduced co-occurrence. Finally we explored whether our experimentally derived assembly rules could simulate realistic communities. Communities simulated using size-based species assembly exhibited diversities closer to wild communities than those simulated using size-independent assembly, with results being sensitive to the combination of rules employed. Hence, species segregation in the wild can be driven by competitive species assembly, and this process is sufficient to generate observed species abundance distributions for tropical epiphyte-dwelling ants.


Assuntos
Formigas , Biota , Espécies Introduzidas , Modelos Biológicos , Animais , Bornéu , Comportamento Competitivo , Simbiose
19.
Oecologia ; 178(2): 441-50, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25575674

RESUMO

Anthropogenic disturbance and the spread of non-native species disrupt natural communities, but also create novel interactions between species. By-product mutualisms, in which benefits accrue as side effects of partner behaviour or morphology, are often non-specific and hence may persist in novel ecosystems. We tested this hypothesis for a two-way by-product mutualism between epiphytic ferns and their ant inhabitants in the Bornean rain forest, in which ants gain housing in root-masses while ferns gain protection from herbivores. Specifically, we assessed how the specificity (overlap between fern and ground-dwelling ants) and the benefits of this interaction are altered by selective logging and conversion to an oil palm plantation habitat. We found that despite the high turnover of ant species, ant protection against herbivores persisted in modified habitats. However, in ferns growing in the oil palm plantation, ant occupancy, abundance and species richness declined, potentially due to the harsher microclimate. The specificity of the fern-ant interactions was also lower in the oil palm plantation habitat than in the forest habitats. We found no correlations between colony size and fern size in modified habitats, and hence no evidence for partner fidelity feedbacks, in which ants are incentivised to protect fern hosts. Per species, non-native ant species in the oil palm plantation habitat (18 % of occurrences) were as important as native ones in terms of fern protection and contributed to an increase in ant abundance and species richness with fern size. We conclude that this by-product mutualism persists in logged forest and oil palm plantation habitats, with no detectable shift in partner benefits. Such persistence of generalist interactions in novel ecosystems may be important for driving ecosystem functioning.


Assuntos
Agricultura , Formigas , Conservação dos Recursos Naturais , Gleiquênias , Herbivoria , Floresta Úmida , Simbiose , Animais , Formigas/classificação , Arecaceae , Bornéu , Resistência à Doença , Ecossistema , Microclima , Doenças das Plantas , Raízes de Plantas , Especificidade da Espécie
20.
Skeletal Radiol ; 44(4): 587-95, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25256753

RESUMO

We report two children with lymphoma of bone centered in the distal femoral epiphysis who presented with knee pain. Radiographs, magnetic resonance imaging (MRI) and computed tomography (CT) were performed on both patients prior to biopsy. Following biopsy, both patients had fluorodeoxyglucose ((18) F-FDG) positron emission tomography/CT (PET/CT) and whole-body technetium-99m (Tc-99m) scintigraphy performed for staging. One patient met the criteria for primary lymphoma of bone. One patient did not meet the criteria for primary lymphoma of bone because of PET uptake in a popliteal, external iliac and possibly lower abdominal node. Both patients responded well to chemotherapy and are disease free more than 7 years after diagnosis. While an epiphyseal presentation of lymphoma of bone is rare, the efficacy of treatment and the compromised outcome associated with diffuse spread of the disease make early recognition by clinicians important. We present these two cases to increase awareness of the disease and to have clinicians consider it in the differential diagnosis of adolescent epiphyseal lesions.


Assuntos
Fêmur/diagnóstico por imagem , Linfoma não Hodgkin/diagnóstico por imagem , Adolescente , Biópsia , Criança , Diagnóstico Diferencial , Epífises/diagnóstico por imagem , Epífises/patologia , Fêmur/patologia , Fluordesoxiglucose F18 , Humanos , Joelho/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Linfoma/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Masculino , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Resultado do Tratamento
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