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1.
Molecules ; 28(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37630384

RESUMO

Tolyporphins were discovered some 30 years ago as part of a global search for antineoplastic compounds from cyanobacteria. To date, the culture HT-58-2, comprised of a cyanobacterium-microbial consortium, is the sole known producer of tolyporphins. Eighteen tolyporphins are now known-each is a free base tetrapyrrole macrocycle with a dioxobacteriochlorin (14), oxochlorin (3), or porphyrin (1) chromophore. Each compound displays two, three, or four open ß-pyrrole positions and two, one, or zero appended C-glycoside (or -OH or -OAc) groups, respectively; the appended groups form part of a geminal disubstitution motif flanking the oxo moiety in the pyrroline ring. The distinct structures and repertoire of tolyporphins stand alone in the large pigments-of-life family. Efforts to understand the cyanobacterial origin, biosynthetic pathways, structural diversity, physiological roles, and potential pharmacological properties of tolyporphins have attracted a broad spectrum of researchers from diverse scientific areas. The identification of putative biosynthetic gene clusters in the HT-58-2 cyanobacterial genome and accompanying studies suggest a new biosynthetic paradigm in the tetrapyrrole arena. The present review provides a comprehensive treatment of the rich science concerning tolyporphins.


Assuntos
Glicosídeos Cardíacos , Cianobactérias , Porfirinas , Tetrapirróis , Cianobactérias/genética , Porfirinas/farmacologia
2.
Brain Behav Immun ; 100: 267-277, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34915155

RESUMO

SARS-CoV-2 infection produces neuroinflammation as well as neurological, cognitive (i.e., brain fog), and neuropsychiatric symptoms (e.g., depression, anxiety), which can persist for an extended period (6 months) after resolution of the infection. The neuroimmune mechanism(s) that produces SARS-CoV-2-induced neuroinflammation has not been characterized. Proposed mechanisms include peripheral cytokine signaling to the brain and/or direct viral infection of the CNS. Here, we explore the novel hypothesis that a structural protein (S1) derived from SARS-CoV-2 functions as a pathogen-associated molecular pattern (PAMP) to induce neuroinflammatory processes independent of viral infection. Prior evidence suggests that the S1 subunit of the SARS-CoV-2 spike protein is inflammatory in vitro and signals through the pattern recognition receptor TLR4. Therefore, we examined whether the S1 subunit is sufficient to drive 1) a behavioral sickness response, 2) a neuroinflammatory response, 3) direct activation of microglia in vitro, and 4) activation of transgenic human TLR2 and TLR4 HEK293 cells. Adult male Sprague-Dawley rats were injected intra-cisterna magna (ICM) with vehicle or S1. In-cage behavioral monitoring (8 h post-ICM) demonstrated that S1 reduced several behaviors, including total activity, self-grooming, and wall-rearing. S1 also increased social avoidance in the juvenile social exploration test (24 h post-ICM). S1 increased and/or modulated neuroimmune gene expression (Iba1, Cd11b, MhcIIα, Cd200r1, Gfap, Tlr2, Tlr4, Nlrp3, Il1b, Hmgb1) and protein levels (IFNγ, IL-1ß, TNF, CXCL1, IL-2, IL-10), which varied across brain regions (hypothalamus, hippocampus, and frontal cortex) and time (24 h and 7d) post-S1 treatment. Direct exposure of microglia to S1 resulted in increased gene expression (Il1b, Il6, Tnf, Nlrp3) and protein levels (IL-1ß, IL-6, TNF, CXCL1, IL-10). S1 also activated TLR2 and TLR4 receptor signaling in HEK293 transgenic cells. Taken together, these findings suggest that structural proteins derived from SARS-CoV-2 might function independently as PAMPs to induce neuroinflammatory processes via pattern recognition receptor engagement.


Assuntos
COVID-19 , Microglia , Animais , Células HEK293 , Humanos , Masculino , Doenças Neuroinflamatórias , Moléculas com Motivos Associados a Patógenos , Ratos , Ratos Sprague-Dawley , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
3.
Molecules ; 27(24)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36557815

RESUMO

A targeted strategy for treating cancer is antibody-directed enzyme prodrug therapy, where the enzyme attached to the antibody causes conversion of an inactive small-molecule prodrug into an active drug. A limitation may be the diffusion of the active drug away from the antibody target site. A related strategy with radiotherapeutics entails enzymatically promoted conversion of a soluble to insoluble radiotherapeutic agent, thereby immobilizing the latter at the target site. Such a molecular brachytherapy has been scarcely investigated. In distinct research, the advent of molecular designs for aggregation-induced emission (AIE) suggests translational use in molecular brachytherapy. Here, several 2-(2-hydroxyphenyl)benzothiazole substrates that readily aggregate in aqueous solution (and afford AIE) were elaborated in this regard. In particular, (1) the 2-(2-hydroxyphenyl) unit was derivatized to bear a pegylated phosphodiester that imparts water solubility yet undergoes enzymatic cleavage, and (2) a p-phenol unit was attached to the benzo moiety to provide a reactive site for final-step iodination (here examined with natural abundance iodide). The pegylated phosphodiester-iodinated benzothiazole undergoes conversion from aqueous-soluble to aqueous-insoluble upon treatment with a phosphatase or phosphodiesterase. The aggregation is essential to molecular brachytherapy, whereas the induced emission of AIE is not essential but provides a convenient basis for research development. Altogether, 21 compounds were synthesized (18 new, 3 known via new routes). Taken together, blending biomedical strategies of enzyme prodrug therapy with materials chemistry concerning substances that undergo AIE may comprise a step forward on the long road toward molecular brachytherapy.


Assuntos
Braquiterapia , Pró-Fármacos , Benzotiazóis , Polietilenoglicóis
4.
Chem Res Toxicol ; 33(9): 2286-2297, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32844644

RESUMO

The aim of this study was to investigate the detailed mechanisms of hepatotoxicity induced by cadmium telluride quantum dots (CdTe-QDs) in BALB/c mice after intravenous injection. The study investigated oxidative stress, apoptosis, and effects on mitochondria as potential mechanistic events to elucidate the observed hepatotoxicity. Oxidative stress in the liver, induced by CdTe-QD exposure, was demonstrated by depletion of total glutathione, an increase in superoxide dismutase activity, and changes in the gene expression of several oxidative stress-related biomarkers. Furthermore, CdTe-QD treatment led to apoptosis in the liver via both intrinsic and extrinsic apoptotic pathways. Effects on mitochondria were evidenced by the enlargement and increase in the number of mitochondria in hepatocytes of treated mice. CdTe-QDs also caused changes in the levels and gene expression of electron transport chain enzymes, depletion of ATP, and an increase in the level of the peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), a regulator of mitochondrial biogenesis. The findings from this study suggest that CdTe-QDs-induced hepatotoxicity might have originated from mitochondrial effects which resulted in oxidative stress and apoptosis in the liver cells. This study provides insight into the biological effects of CdT-QDs at the tissue level and the detailed mechanisms of their toxicity in animals. The study also provides important data for bridging the gap between in vitro and in vivo testing and risk assessment of these NPs.


Assuntos
Compostos de Cádmio/toxicidade , Hepatócitos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Pontos Quânticos/toxicidade , Telúrio/toxicidade , Animais , Relação Dose-Resposta a Droga , Hepatócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/metabolismo
5.
Proteomics ; 19(13): e1800394, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31070281

RESUMO

Exosomes are membrane-bound vesicles that traffic small molecular cargos. These cargos participate in cell-cell communication and contribute to the pathogenesis of many disease including cancer. How these mechanisms contribute to communication within the pancreatic adenocarcinoma (PDAC) microenvironment and how they contribute to PDAC biology are poorly understood. Performed in this study are comprehensive, quantitative comparisons of the proteomes of three PDAC cell lines to those of the exosomes they produce. Approximately 35% of whole cell proteins sort into exosomes. Analysis of composition of microbiomes (ANCOM) determined a cluster of 98 enriched pancreatic cancer exosome core proteins (ePC-ECPs). Further, these proteins are predicted by ingenuity pathway analysis (IPA) as actively involved in signaling pathways regulating cell death and survival, cellular movement, and cell-to-cell signaling and interaction in particular (top three p-value significant pathways). Significant enrichment of canonical pathways of acute phase response signaling (inflammatory response signaling pathways) and FXR and RXR activation in biosynthetic pathways are also predicted; 97 ePC-ECPs are associated with cancer and among them, 34 are specifically associated with PDAC. In conclusion, exosomes from PDAC are enriched with cancer-associated signaling proteins. Further assessment of these proteins as PDAC biomarkers or therapeutic targets is warranted.


Assuntos
Adenocarcinoma/patologia , Exossomos/metabolismo , Neoplasias Pancreáticas/patologia , Proteoma/metabolismo , Biomarcadores Tumorais/metabolismo , Comunicação Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Sobrevivência Celular/fisiologia , Humanos , Transdução de Sinais , Microambiente Tumoral , Neoplasias Pancreáticas
6.
Chem Res Toxicol ; 32(8): 1491-1503, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31251591

RESUMO

Quantum dots (QDs) are engineered nanoparticles (NPs) of semiconductor structure that possess unique optical and electronic properties and are widely used in biomedical applications; however, their risks are not entirely understood. This study investigated the tissue distribution and toxic effects of cadmium telluride quantum dots (CdTe-QDs) in male BALB/c mice for up to 1 week after single-dose intravenous injections. CdTe-QDs were detected in the blood, lung, heart, liver, spleen, kidney, testis and brain. Most CdTe-QDs accumulated in the liver, followed by the spleen and kidney. At high doses, exposure to CdTe-QDs resulted in mild dehydration, lethargy, ruffled fur, hunched posture, and body weight loss. Histological analysis of the tissues, upon highest dose exposures, revealed hepatic hemorrhage and necrotic areas in the spleen. The sera of mice treated with high doses of CdTe-QDs showed significant increases in alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin levels, as well as a reduction in albumin. CdTe-QD exposure also led to a reduced number of platelets and elevated total white blood cell counts, including monocytes and neutrophils, serum amyloid A, and several pro-inflammatory cytokines. These results demonstrated that the liver is the main target of CdTe-QDs and that exposure to CdTe-QDs leads to hepatic and splenic injury, as well as systemic effects, in mice. By contrast, cadmium chloride (CdCl2), at an equivalent concentration of cadmium, appeared to have a different pharmacokinetic pattern from that of CdTe-QDs, having minimal effects on the aforementioned parameters, suggesting that cadmium alone cannot fully explain the toxicity of CdTe-QDs.


Assuntos
Compostos de Cádmio/farmacocinética , Nanopartículas/química , Pontos Quânticos/química , Telúrio/farmacocinética , Alanina Transaminase/química , Alanina Transaminase/metabolismo , Albuminas/química , Albuminas/metabolismo , Animais , Aspartato Aminotransferases/química , Aspartato Aminotransferases/metabolismo , Bilirrubina/sangue , Cloreto de Cádmio/administração & dosagem , Cloreto de Cádmio/metabolismo , Cloreto de Cádmio/farmacocinética , Compostos de Cádmio/administração & dosagem , Compostos de Cádmio/metabolismo , Injeções Intravenosas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/metabolismo , Pontos Quânticos/metabolismo , Telúrio/administração & dosagem , Telúrio/metabolismo , Distribuição Tecidual
7.
Bioorg Med Chem Lett ; 26(13): 3187-3191, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27173800

RESUMO

PIM1 is a proto-oncogene encoding the serine/threonine PIM1 kinase. PIM1 kinase plays important roles in regulating aspects of cell cycle progression, apoptosis resistance, and has been implicated in the development of such malignancies as prostate cancer and acute myeloid leukemia among others. Knockout of PIM1 kinase in mice has been shown to be non-lethal without any obvious phenotypic changes, making it an attractive therapeutic target. Our investigation of anthraquinones as kinase inhibitors revealed a series of quinone analogs showing high selectivity for inhibition of the PIM kinases. Molecular modeling studies were used to identify key interactions and binding poses of these compounds within the PIM1 binding pocket. Compounds 1, 4, 7 and 9 inhibited the growth of DU-145 prostate cancer cell lines with a potency of 8.21µM, 4.06µM, 3.21µM and 2.02µM.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-pim-1/antagonistas & inibidores , Quinonas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Estrutura Molecular , Neoplasias da Próstata/patologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Quinonas/síntese química , Quinonas/química , Relação Estrutura-Atividade
10.
Anal Biochem ; 483: 40-6, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25957125

RESUMO

Flow cytometry was evaluated for its capacity to detect and distinguish a wide size range (20-2000 nm) of fluorescent polystyrene particles (PSPs). Side scatter and fluorescence parameters could predict dispersed PSP sizes down to 200 nm, but the forward scatter parameter was not discriminatory. Confocal microscopy of flow-sorted fractions confirmed that dispersed PSPs appeared as a single sharp peak on fluorescence histograms, whereas agglomerated PSPs were detected as smaller adjacent peaks. Particles as small as 200 nm could also be detected by flow cytometry after they were first phagocytized by J774A.1 murine macrophages. Confocal microscopy demonstrated that these PSPs were internalized within the cytoplasm. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] and calcein-AM (acetoxymethyl ester) assays showed that they were not cytotoxic. Internalized PSP size correlated to both cellular side scatter (R(2)=0.9821) and fluorescence intensity (R(2)=0.9993). Furthermore, PSPs of various sizes could be distinguished when J774A.1 cells were loaded with a single size of PSP and mixed with cells containing other sizes. However, spectra of cells loaded with a mixture of PSP sizes resembled those containing only the largest PSP. These data demonstrate the capacity and limitations of phagocytosis-coupled flow cytometry to distinguish between dispersed and agglomerated states and detect a wide size range of particles.


Assuntos
Ânions/química , Citometria de Fluxo/métodos , Tamanho da Partícula , Fagocitose , Poliestirenos/química , Animais , Morte Celular , Linhagem Celular , Espaço Intracelular/metabolismo , Camundongos , Microscopia
11.
Anal Biochem ; 472: 67-74, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25481739

RESUMO

A multiplexing bead-based platform provides an approach for the development of assays targeting specific analytes for biomonitoring and biosensing applications. Multi-Analyte Profiling (xMAP) assays typically employ a sandwich-type format using antibodies for the capture and detection of analytes of interest, and the system permits the simultaneous quantitation of multiple targets. In this study, an aptamer/antibody assay for the detection of C-reactive protein (CRP) was developed. CRP is an acute phase marker of inflammation whose elevated basal levels are correlated with an increased risk for a number of pathologies. For this assay, an RNA aptamer that binds CRP was conjugated to beads to act as the capture agent. Biotinylated anti-CRP antibody coupled to fluorescently labeled streptavidin was used for quantification of CRP. The detection limit of the CRP assay was 0.4 mg/L in diluted serum. The assay was then used to detect spiked CRP samples in the range of 0.4 to 10mg/L in diluted serum with acceptable recoveries (extrapolated values of 70-130%), including that of a certified reference material (129% recovery). The successful incorporation of the CRP aptamer into this platform demonstrates that the exploration of other aptamer-target systems could increase the number of analytes measurable using xMAP-type assays.


Assuntos
Anticorpos/química , Aptâmeros de Nucleotídeos/química , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Humanos , Inflamação/sangue
12.
J Lipid Res ; 55(11): 2370-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25258384

RESUMO

LDL cholesterol (LDL-C) contributes to coronary heart disease. Proprotein convertase subtilisin/kexin type 9 (PCSK9) increases LDL-C by inhibiting LDL-C clearance. The therapeutic potential for PCSK9 inhibitors is highlighted by the fact that PCSK9 loss-of-function carriers exhibit 15-30% lower circulating LDL-C and a disproportionately lower risk (47-88%) of experiencing a cardiovascular event. Here, we utilized pcsk9(-/-) mice and an anti-PCSK9 antibody to study the role of the LDL receptor (LDLR) and ApoE in PCSK9-mediated regulation of plasma cholesterol and atherosclerotic lesion development. We found that circulating cholesterol and atherosclerotic lesions were minimally modified in pcsk9(-/-) mice on either an LDLR- or ApoE-deficient background. Acute administration of an anti-PCSK9 antibody did not reduce circulating cholesterol in an ApoE-deficient background, but did reduce circulating cholesterol (-45%) and TGs (-36%) in APOE*3Leiden.cholesteryl ester transfer protein (CETP) mice, which contain mouse ApoE, human mutant APOE3*Leiden, and a functional LDLR. Chronic anti-PCSK9 antibody treatment in APOE*3Leiden.CETP mice resulted in a significant reduction in atherosclerotic lesion area (-91%) and reduced lesion complexity. Taken together, these results indicate that both LDLR and ApoE are required for PCSK9 inhibitor-mediated reductions in atherosclerosis, as both are needed to increase hepatic LDLR expression.


Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/metabolismo , Colesterol/sangue , Fígado/metabolismo , Pró-Proteína Convertases/metabolismo , Receptores de LDL/metabolismo , Serina Endopeptidases/metabolismo , Animais , Anticorpos/imunologia , Aterosclerose/sangue , Aterosclerose/enzimologia , Aterosclerose/genética , Proteínas de Transferência de Ésteres de Colesterol/metabolismo , Feminino , Técnicas de Inativação de Genes , Humanos , Fígado/efeitos dos fármacos , Camundongos , Pró-Proteína Convertase 9 , Pró-Proteína Convertases/deficiência , Pró-Proteína Convertases/genética , Pró-Proteína Convertases/imunologia , Serina Endopeptidases/deficiência , Serina Endopeptidases/genética , Serina Endopeptidases/imunologia
13.
J Leukoc Biol ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38547428

RESUMO

Asthma affects 25 million Americans and recent advances in treatment are effective for only a portion of severe asthma patients. Triggering Receptor Expressed on Myeloid cells 1 (TREM-1), an innate receptor that canonically amplifies inflammatory signaling in neutrophils and monocytes, plays a central role in regulating lung inflammation. It is unknown how TREM-1 contributes to allergic asthma pathology. Utilizing a murine model of asthma, flow cytometry revealed TREM-1+ eosinophils in the lung tissue and airway during allergic airway inflammation. TREM-1 expression was restricted to recruited, inflammatory eosinophils. Expression was induced on bone marrow derived eosinophils by incubation with IL-33, LPS, or GM-CSF. Compared to TREM-1- airway eosinophils, TREM-1+ eosinophils were enriched for pro-inflammatory gene sets including migration, respiratory burst, and cytokine production. Unexpectedly, eosinophil-specific ablation of TREM-1 exacerbated airway IL-5 production, airway MUC5AC production, and lung tissue eosinophil accumulation. Further investigation of transcriptional data revealed apoptosis and superoxide generation related gene sets were enriched in TREM-1+ eosinophils. Consistent with these findings, Annexin V and Caspase 3/7 staining demonstrated higher rates of apoptosis among TREM-1+ eosinophils compared to TREM-1- eosinophils in the inflammatory airway. In vitro, Trem1/3-/- bone marrow derived eosinophils consumed less oxygen than WT in response to PMA, suggesting that TREM-1 promotes superoxide generation in eosinophils. These data reveal protein level expression of TREM-1 by eosinophils, define a population of TREM-1+ inflammatory eosinophils, and demonstrate that eosinophil TREM-1 restricts key features of type 2 lung inflammation.

14.
Int J Neonatal Screen ; 10(2)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38804359

RESUMO

Newborn screening (NBS) is hailed as a public health success, but little is known about the long-term outcomes following a positive newborn screen. There has been difficulty gathering long-term follow-up (LTFU) data consistently, reliably, and with minimal effort. Six programs developed and tested a core set of minimal LTFU data elements. After an iterative data collection process and the development of a data collection tool, the group agreed on the minimal LTFU data elements. The denominator captured all infants with an NBS diagnosis, accounting for children who moved or died prior to the follow-up year. They also agreed on three LTFU outcomes: if the child was still alive, had contact with a specialist, and received appropriate care specific to their diagnosis within the year. The six programs representing NBS public health programs, clinical providers, and research programs provided data across multiple NBS disorders. In 2022, 83.8% (563/672) of the children identified by the LTFU programs were alive and living in the jurisdiction; of those, 92.0% (518/563) saw a specialist, and 87.7% (494/563) received appropriate care. The core LTFU data elements can be applied as a foundation to address the impact of early diagnosis by NBS within and across jurisdictions.

15.
Nat Med ; 30(4): 1054-1064, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38641742

RESUMO

Globally, lung cancer is the leading cause of cancer death. Previous trials demonstrated that low-dose computed tomography lung cancer screening of high-risk individuals can reduce lung cancer mortality by 20% or more. Lung cancer screening has been approved by major guidelines in the United States, and over 4,000 sites offer screening. Adoption of lung screening outside the United States has, until recently, been slow. Between June 2017 and May 2019, the Ontario Lung Cancer Screening Pilot successfully recruited 7,768 individuals at high risk identified by using the PLCOm2012noRace lung cancer risk prediction model. In total, 4,451 participants were successfully screened, retained and provided with high-quality follow-up, including appropriate treatment. In the Ontario Lung Cancer Screening Pilot, the lung cancer detection rate and the proportion of early-stage cancers were 2.4% and 79.2%, respectively; serious harms were infrequent; and sensitivity to detect lung cancers was 95.3% or more. With abnormal scans defined as ones leading to diagnostic investigation, specificity was 95.5% (positive predictive value, 35.1%), and adherence to annual recall and early surveillance scans and clinical investigations were high (>85%). The Ontario Lung Cancer Screening Pilot provides insights into how a risk-based organized lung screening program can be implemented in a large, diverse, populous geographic area within a universal healthcare system.


Assuntos
Neoplasias Pulmonares , Humanos , Estados Unidos , Neoplasias Pulmonares/diagnóstico por imagem , Detecção Precoce de Câncer/métodos , Assistência de Saúde Universal , Pulmão , Tomografia Computadorizada por Raios X
16.
Proc Biol Sci ; 280(1758): 20130176, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23466987

RESUMO

Individuals of many species produce distinctive vocalizations that may relay potential information about the signaller. The alarm calls of some species have been reported to be individually specific, and this distinctiveness may allow individuals to access the reliability or kinship of callers. While not much is known generally about the heritability of mammalian vocalizations, if alarm calls were individually distinctive to permit kinship assessment, then call structure should be heritable. Here, we show conclusively for the first time that alarm call structure is heritable. We studied yellow-bellied marmots (Marmota flaviventris) and made nine quantitative measurements of their alarm calls. With a known genealogy, we used the animal model (a statistical technique) to estimate alarm call heritability. In juveniles, only one of the measured variables had heritability significantly different from zero; however, most variables had significant maternal environmental effects. By contrast, yearlings and adults had no significant maternal environmental effects, but the heritability of nearly all measured variables was significantly different from zero. Some, but not all of these heritable effects were significantly different across age classes. The presence of significantly non-zero maternal environmental effects in juveniles could reflect the impact of maternal environmental stresses on call structure. Regardless of this mechanism, maternal environmental effects could permit kinship recognition in juveniles. In older animals, the substantial genetic basis of alarm call structure suggests that calls could be used to assess kinship and, paradoxically, might also suggest a role of learning in call structure.


Assuntos
Marmota/fisiologia , Vocalização Animal , Envelhecimento , Animais , Colorado , Feminino , Masculino , Marmota/genética , Marmota/crescimento & desenvolvimento , Característica Quantitativa Herdável , Espectrografia do Som
17.
Artigo em Inglês | MEDLINE | ID: mdl-36981667

RESUMO

University students experience a high level of stress, which could potentially affect how they manage stressful situations beyond university, such as when entering the workforce. Although universities offer counseling services and various health promotion programs, there is reluctance and negative perceptions about utilizing these from students. Further research is needed to explore the effectiveness of therapy dog interventions in human interactions that is quantifiable and embraces the elements of health promotion. This study aimed to investigate the impact of therapy dog interventions on students' moods across a multi-campus university during a 2-week final examination period. Two hundred and sixty-five students participated in the study involving a multi-campus university. The intervention group and control group completed a questionnaire involving the positive affect negative affect schedule (PANAS), a 20-item scale that measures a person's affect at the time. The intervention group (n = 170) had a higher average of total PANAS scores (mean = 77.63, standard deviation = 10.975) compared to the control group (n = 95) (mean = 69.41, standard deviation = 13.442). The results were statistically significant (mean difference = 8.219, 95% CI = 5.213-11.224, p < 0.05) with a t-score of 5.385. Students who engaged with therapy dogs on campus during the examination period were more likely to have a more positive affect. The results suggest that universities should include therapy dog programs within their health promotion programs for students, as these may help improve their mood and reduce the stress associated with university examinations.


Assuntos
Afeto , Animais de Terapia , Cães , Animais , Humanos , Universidades , Estudantes/psicologia , Promoção da Saúde
18.
Mol Pharmacol ; 82(5): 843-59, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22859723

RESUMO

Activation of FFA1 (GPR40), a member of G protein-coupling receptor family A, is mediated by medium- and long-chain fatty acids and leads to amplification of glucose-stimulated insulin secretion, suggesting a potential role for free fatty acid 1 (FFA1) as a target for type 2 diabetes. It was assumed previously that there is a single binding site for fatty acids and synthetic FFA1 agonists. However, using members of two chemical series of partial and full agonists that have been identified, radioligand binding interaction studies revealed that the full agonists do not bind to the same site as the partial agonists but exhibit positive heterotropic cooperativity. Analysis of functional data reveals positive functional cooperativity between the full agonists and partial agonists in various functional assays (in vitro and ex vivo) and also in vivo. Furthermore, the endogenous fatty acid docosahexaenoic acid (DHA) shows negative or neutral cooperativity with members of both series of agonists in binding assays but displays positive cooperativity in functional assays. Another synthetic agonist is allosteric with members of both agonist series, but apparently competitive with DHA. Therefore, there appear to be three allosterically linked binding sites on FFA1 with agonists specific for each of these sites. Activation of free fatty acid 1 receptor (FFAR1) by each of these agonists is differentially affected by mutations of two arginine residues, previously found to be important for FFAR1 binding and activation. These ligands with their high potencies and strong positive functional cooperativity with endogenous fatty acids, demonstrated in vitro and in vivo, have the potential to deliver therapeutic benefits.


Assuntos
Hipoglicemiantes/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Sítio Alostérico , Animais , Arginina/genética , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Linhagem Celular , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Agonismo Parcial de Drogas , Sinergismo Farmacológico , Teste de Tolerância a Glucose , Humanos , Técnicas In Vitro , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Fenilpropionatos/química , Fenilpropionatos/farmacologia , Ensaio Radioligante , Receptores Acoplados a Proteínas G/genética , Relação Estrutura-Atividade
19.
Bioorg Med Chem Lett ; 22(2): 1267-70, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22217876

RESUMO

The discovery that certain long chain fatty acids potentiate glucose stimulated insulin secretion through the previously orphan receptor GPR40 sparked interest in GPR40 agonists as potential antidiabetic agents. Optimization of a series of ß-substituted phenylpropanoic acids led to the identification of (S)-3-(4-((4'-(trifluoromethyl)biphenyl-3-yl)methoxy)phenyl)hex-4-ynoic acid (AMG 837) as a potent GPR40 agonist with a superior pharmacokinetic profile and robust glucose-dependent stimulation of insulin secretion in rodents.


Assuntos
Compostos de Bifenilo/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Administração Oral , Animais , Disponibilidade Biológica , Compostos de Bifenilo/administração & dosagem , Compostos de Bifenilo/química , Relação Dose-Resposta a Droga , Camundongos , Camundongos Knockout , Estrutura Molecular , Receptores Acoplados a Proteínas G/deficiência , Receptores Acoplados a Proteínas G/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade
20.
Int Cybersecur Law Rev ; 3(2): 437-465, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37520586

RESUMO

Do you use Office 365 or Windows 10? How about GoDaddy to support your website? Has it been a while since you connected your iPhone to Wi-Fi instead of merely running off your data? Or is your Samsung phone more than 2 years old? Would it surprise you to learn that some of these products no longer receive security support or automatic updates? If so, you may be surprised to hear that you are being exposed to security risks, as many cyber incidences are the direct result of an absence of security patching and automatic updates. There are many reasons for this. Most companies provide security patches, but they are not always timely and many are not automated, requiring manual effort (often unbeknownst to consumers and businesses). Timely security patching is, upon discovery or notification of a security flaw in a system or product, the release of a security update within a reasonable time that patches and updates the security of a system-sometimes this is automatic, sometimes the security patch is merely a notification that you can and should patch your own system. A contributing factor to this is that there is no legal obligation to provide security support, let alone timely security support. This means that there is no legal requirement to patch known security vulnerabilities and bugs or issue automatic updates. This paper asks whether or not Australia should have a legal obligation to ensure timely security patching and require automatic updates by default in all consumer systems. Our conclusion: yes, it should, since many companies cannot be relied on to self-regulate and put their client's security interests first, and the stakes in cybersecurity have become too high to continue with the status quo. We conclude by presenting our recommended pathway for legal reform.

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