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1.
Nature ; 569(7756): 423-427, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31043741

RESUMO

Mutations in the retinoblastoma (RB) tumour suppressor pathway are a hallmark of cancer and a prevalent feature of lung adenocarcinoma1-3. Although RB was the first tumour suppressor to be identified, the molecular and cellular basis that underlies selection for persistent RB loss in cancer remains unclear4-6. Methods that reactivate the RB pathway using inhibitors of cyclin-dependent kinases CDK4 and CDK6 are effective in some cancer types and are currently under evaluation for the treatment of lung adenocarcinoma7-9. Whether RB pathway reactivation will have therapeutic effects and whether targeting CDK4 and CDK6 is sufficient to reactivate RB pathway activity in lung cancer remains unknown. Here we model RB loss during lung adenocarcinoma progression and pathway reactivation in established oncogenic KRAS-driven tumours in mice. We show that RB loss enables cancer cells to bypass two distinct barriers during tumour progression. First, RB loss abrogates the requirement for amplification of the MAPK signal during malignant progression. We identify CDK2-dependent phosphorylation of RB as an effector of MAPK signalling and critical mediator of resistance to inhibition of CDK4 and CDK6. Second, RB inactivation deregulates the expression of cell-state-determining factors, facilitates lineage infidelity and accelerates the acquisition of metastatic competency. By contrast, reactivation of RB reprograms advanced tumours towards a less metastatic cell state, but is nevertheless unable to halt cancer cell proliferation and tumour growth due to adaptive rewiring of MAPK pathway signalling, which restores a CDK-dependent suppression of RB. Our study demonstrates the power of reversible gene perturbation approaches to identify molecular mechanisms of tumour progression, causal relationships between genes and the tumour suppressive programs that they control and critical determinants of successful cancer therapy.


Assuntos
Linhagem da Célula , Progressão da Doença , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Metástase Neoplásica , Retinoblastoma/metabolismo , Células 3T3 , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Linhagem da Célula/genética , Quinase 2 Dependente de Ciclina/deficiência , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Células HEK293 , Humanos , Neoplasias Pulmonares/genética , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Metástase Neoplásica/genética , Retinoblastoma/genética
2.
PLoS Genet ; 17(12): e1009941, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34879057

RESUMO

The retinoblastoma (RB) tumor suppressor is functionally inactivated in a wide range of human tumors where this inactivation promotes tumorigenesis in part by allowing uncontrolled proliferation. RB has been extensively studied, but its mechanisms of action in normal and cancer cells remain only partly understood. Here, we describe a new mouse model to investigate the consequences of RB depletion and its re-activation in vivo. In these mice, induction of shRNA molecules targeting RB for knock-down results in the development of phenotypes similar to Rb knock-out mice, including the development of pituitary and thyroid tumors. Re-expression of RB leads to cell cycle arrest in cancer cells and repression of transcriptional programs driven by E2F activity. Thus, continuous RB loss is required for the maintenance of tumor phenotypes initiated by loss of RB, and this new mouse model will provide a new platform to investigate RB function in vivo.


Assuntos
Neoplasias Hipofisárias/genética , Proteínas de Ligação a Retinoblastoma/genética , Neoplasias da Glândula Tireoide/genética , Animais , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Fatores de Transcrição E2F/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Células NIH 3T3 , Neoplasias Hipofisárias/patologia , RNA Interferente Pequeno/metabolismo , Neoplasias da Glândula Tireoide/patologia
3.
Annu Rev Entomol ; 68: 69-88, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36170643

RESUMO

Mites are masters at attaching to larger animals, often insects, in a temporary symbiosis called phoresy that allows these tiny animals to exploit patchy resources. In this article, we examine phoresy in the Acari, including those that feed on their carriers in transit, from a broad perspective. From a phylogenetic perspective, phoresy has evolved several times from free-living ancestors but also has been lost frequently. Rotting logs appear to be the first patchy resource exploited by phoretic mites, but the evolution of rapid life cycles later permitted exploitation of short-lived resources. As phoresy is a temporary symbiosis, most species have off-host interactions with their carrier. These relationships can be highly complex and context dependent but often are exploitative of the carrier's resources or progeny. Transitions from phoresy to parasitism seem widespread, but evidence for transitions from obligate phoretic parasitism to permanent parasitism is weak.


Assuntos
Ácaros , Animais , Filogenia , Estágios do Ciclo de Vida , Simbiose
4.
Glob Chang Biol ; 28(2): 588-611, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34562049

RESUMO

High-quality atmospheric CO2  measurements are sparse in Amazonia, but can provide critical insights into the spatial and temporal variability of sources and sinks of CO2 . In this study, we present the first 6 years (2014-2019) of continuous, high-precision measurements of atmospheric CO2 at the Amazon Tall Tower Observatory (ATTO, 2.1°S, 58.9°W). After subtracting the simulated background concentrations from our observational record, we define a CO2 regional signal ( ΔCO2obs ) that has a marked seasonal cycle with an amplitude of about 4 ppm. At both seasonal and inter-annual scales, we find differences in phase between ΔCO2obs and the local eddy covariance net ecosystem exchange (EC-NEE), which is interpreted as an indicator of a decoupling between local and non-local drivers of ΔCO2obs . In addition, we present how the 2015-2016 El Niño-induced drought was captured by our atmospheric record as a positive 2σ anomaly in both the wet and dry season of 2016. Furthermore, we analyzed the observed seasonal cycle and inter-annual variability of ΔCO2obs together with net ecosystem exchange (NEE) using a suite of modeled flux products representing biospheric and aquatic CO2 exchange. We use both non-optimized and optimized (i.e., resulting from atmospheric inverse modeling) NEE fluxes as input in an atmospheric transport model (STILT). The observed shape and amplitude of the seasonal cycle was captured neither by the simulations using the optimized fluxes nor by those using the diagnostic Vegetation and Photosynthesis Respiration Model (VPRM). We show that including the contribution of CO2 from river evasion improves the simulated shape (not the magnitude) of the seasonal cycle when using a data-driven non-optimized NEE product (FLUXCOM). The simulated contribution from river evasion was found to be 25% of the seasonal cycle amplitude. Our study demonstrates the importance of the ATTO record to better understand the Amazon carbon cycle at various spatial and temporal scales.


Assuntos
Dióxido de Carbono , Ecossistema , Ciclo do Carbono , Rios , Estações do Ano
5.
Nature ; 539(7629): 416-419, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27776357

RESUMO

The nucleation of atmospheric vapours is an important source of new aerosol particles that can subsequently grow to form cloud condensation nuclei in the atmosphere. Most field studies of atmospheric aerosols over continents are influenced by atmospheric vapours of anthropogenic origin (for example, ref. 2) and, in consequence, aerosol processes in pristine, terrestrial environments remain poorly understood. The Amazon rainforest is one of the few continental regions where aerosol particles and their precursors can be studied under near-natural conditions, but the origin of small aerosol particles that grow into cloud condensation nuclei in the Amazon boundary layer remains unclear. Here we present aircraft- and ground-based measurements under clean conditions during the wet season in the central Amazon basin. We find that high concentrations of small aerosol particles (with diameters of less than 50 nanometres) in the lower free troposphere are transported from the free troposphere into the boundary layer during precipitation events by strong convective downdrafts and weaker downward motions in the trailing stratiform region. This rapid vertical transport can help to maintain the population of particles in the pristine Amazon boundary layer, and may therefore influence cloud properties and climate under natural conditions.


Assuntos
Aerossóis/análise , Chuva , Aerossóis/química , Biomassa , Brasil , Incêndios , Tamanho da Partícula , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química
6.
Protein Expr Purif ; 144: 55-61, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29223927

RESUMO

The cystine-knot metallocarboxypeptidase inhibitors (MCPIs) are peptides that contribute to control proteolytic activity, involved in storage, growth and maintenance of plants. Lately studies reported several MCPIs with potential use in biomedical applications; as anti-cancer, anti-thrombotic, anti-malaric and anti-angiogenic agents. We report the isolation, purification, chemical stability and biochemical characterization of a novel carboxypeptidase A inhibitor (YBPCI) isolated from Capsicum annuum L. var. Yellow Bell Pepper, the first cystine-knot miniprotein (CKM) of the species. We demonstrate the stability of YBPCI (IC50 = 0.90 µg/ml) to high temperatures, high salt concentration and extreme pH values. MALDI-TOF/MS analysis detected a molecular weight of 4057 Da, and peptide mass fingerprint resulted in no matches with other protease inhibitors. In vitro gastrointestinal digestion subjecting YBPCI to pH 2 incubation and proteolytic attack resulted in complete inhibitory activity. To summarize, there are no reports to date of carboxypeptidase inhibitors in C. annuum species, giving our report much more relevance.


Assuntos
Carboxipeptidases/antagonistas & inibidores , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/farmacologia , Inibidores de Proteases/farmacologia , Animais , Capsicum/química , Bovinos , Extratos Vegetais/química , Proteínas de Plantas/análise , Inibidores de Proteases/análise , Inibidores de Proteases/isolamento & purificação
7.
Int J Mol Sci ; 19(3)2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29495576

RESUMO

Cystine-knot miniproteins (CKMPs) are an intriguing group of cysteine-rich molecules that combine the characteristics of proteins and peptides. Typically, CKMPs are fewer than 50 residues in length and share a characteristic knotted scaffold characterized by the presence of three intramolecular disulfide bonds that form the singular knotted structure. The knot scaffold confers on these proteins remarkable chemical, thermal, and proteolytic stability. Recently, CKMPs have emerged as a novel class of natural molecules with interesting pharmacological properties. In the present work, a novel cystine-knot metallocarboxypeptidase inhibitor (chuPCI) was isolated from tubers of Solanum tuberosum, subsp. andigenum cv. Churqueña. Our results demonstrated that chuPCI is a member of the A/B-type family of metallocarboxypeptidases inhibitors. chuPCI was expressed and characterized by a combination of biochemical and mass spectrometric techniques. Direct comparison of the MALDI-TOF mass spectra for the native and recombinant molecules allowed us to confirm the presence of four different forms of chuPCI in the tubers. The majority of such forms have a molecular weight of 4309 Da and contain a cyclized Gln in the N-terminus. The other three forms are derived from N-terminal and/or C-terminal proteolytic cleavages. Taken together, our results contribute to increase the current repertoire of natural CKMPs.


Assuntos
Miniproteínas Nó de Cistina/química , Proteínas de Plantas/química , Proteômica , Proteínas Recombinantes , Solanum tuberosum/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Sequência de Aminoácidos , Animais , Carboxipeptidases/antagonistas & inibidores , Bovinos , Clonagem Molecular , Miniproteínas Nó de Cistina/análise , Miniproteínas Nó de Cistina/genética , Miniproteínas Nó de Cistina/isolamento & purificação , Ativação Enzimática/efeitos dos fármacos , Cinética , Proteínas de Plantas/análise , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Inibidores de Proteases/análise , Inibidores de Proteases/química , Inibidores de Proteases/isolamento & purificação , Inibidores de Proteases/farmacologia , Proteômica/métodos , Análise de Sequência de DNA , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Suínos
8.
Semin Cancer Biol ; 37-38: 16-25, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26805514

RESUMO

A dividing cell has to duplicate its DNA precisely once during the cell cycle to preserve genome integrity avoiding the accumulation of genetic aberrations that promote diseases such as cancer. A large number of endogenous impacts can challenge DNA replication and cells harbor a battery of pathways to promote genome integrity during DNA replication. This includes suppressing new replication origin firing, stabilization of replicating forks, and the safe restart of forks to prevent any loss of genetic information. Here, we describe mechanisms by which oncogenes can interfere with DNA replication thereby causing DNA replication stress and genome instability. Further, we describe cellular and systemic responses to these insults with a focus on DNA replication restart pathways. Finally, we discuss the therapeutic potential of exploiting intrinsic replicative stress in cancer cells for targeted therapy.


Assuntos
Replicação do DNA , Neoplasias/genética , Medicina de Precisão/métodos , Origem de Replicação , Dano ao DNA , Instabilidade Genômica , Humanos , Neoplasias/terapia , Oncogenes
9.
PLoS Genet ; 10(1): e1004095, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24497836

RESUMO

Monoubiquitination of histone H2B lysine 123 regulates methylation of histone H3 lysine 4 (H3K4) and 79 (H3K79) and the lack of H2B ubiquitination in Saccharomyces cerevisiae coincides with metacaspase-dependent apoptosis. Here, we discovered that loss of H3K4 methylation due to depletion of the methyltransferase Set1p (or the two COMPASS subunits Spp1p and Bre2p, respectively) leads to enhanced cell death during chronological aging and increased sensitivity to apoptosis induction. In contrast, loss of H3K79 methylation due to DOT1 disruption only slightly affects yeast survival. SET1 depleted cells accumulate DNA damage and co-disruption of Dot1p, the DNA damage adaptor protein Rad9p, the endonuclease Nuc1p, and the metacaspase Yca1p, respectively, impedes their early death. Furthermore, aged and dying wild-type cells lose H3K4 methylation, whereas depletion of the H3K4 demethylase Jhd2p improves survival, indicating that loss of H3K4 methylation is an important trigger for cell death in S. cerevisiae. Given the evolutionary conservation of H3K4 methylation this likely plays a role in apoptosis regulation in a wide range of organisms.


Assuntos
Apoptose/genética , Histona-Lisina N-Metiltransferase/genética , Histonas/genética , Proteínas Nucleares/genética , Proteínas de Saccharomyces cerevisiae/genética , Sobrevivência Celular/genética , Dano ao DNA/genética , Histona Desmetilases com o Domínio Jumonji/genética , Lisina/genética , Metilação , Saccharomyces cerevisiae , Ubiquitinação/genética
10.
J Nematol ; 49(3): 327-333, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29062157

RESUMO

Protogamasellus mica was extracted from a sugarcane field in Australia and cultured on bacterial-feeding nematodes. Studies with various nematodes in laboratory arenas showed that one mite and its progeny reduced nematode numbers by between 26 and 50 nematodes/day. A bacterivore (Mesorhabditis sp.), a fungivore (Aphelenchus avenae), and two plant parasites (root-knot nematode, Meloidogyne javanica and root-lesion nematode, Pratylenchus zeae) were all reduced at much the same rate despite the fact that the nematodes are quite different in size and motility and belong to different trophic groups. When sugarcane was grown in the greenhouse for 8 wk, stunt nematode (Tylenchorhynchus annulatus), a plant parasite that feeds ectoparasitically on roots, was almost eliminated from pots inoculated with the mite, and numbers of microbivores and root-lesion nematode were markedly reduced. Huge reductions in nematode populations were also observed when mites were added to microcosms containing small quantities of defaunated soil. These results show that P. mica multiplies rapidly when nematodes are available as a food source and has the capacity to play a role in regulating populations of both plant-parasitic and free-living nematodes. Future research should focus on understanding the crop and soil management practices required to enable this mite and other predatory species to thrive.

11.
Proc Natl Acad Sci U S A ; 110(42): 16856-61, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24082115

RESUMO

DNA damage can obstruct replication forks, resulting in replicative stress. By siRNA screening, we identified kinases involved in the accumulation of phosphohistone 2AX (γH2AX) upon UV irradiation-induced replication stress. Surprisingly, the strongest reduction of phosphohistone 2AX followed knockdown of the MAP kinase-activated protein kinase 2 (MK2), a kinase currently implicated in p38 stress signaling and G2 arrest. Depletion or inhibition of MK2 also protected cells from DNA damage-induced cell death, and mice deficient for MK2 displayed decreased apoptosis in the skin upon UV irradiation. Moreover, MK2 activity was required for damage response, accumulation of ssDNA, and decreased survival when cells were treated with the nucleoside analogue gemcitabine or when the checkpoint kinase Chk1 was antagonized. By using DNA fiber assays, we found that MK2 inhibition or knockdown rescued DNA replication impaired by gemcitabine or by Chk1 inhibition. This rescue strictly depended on translesion DNA polymerases. In conclusion, instead of being an unavoidable consequence of DNA damage, alterations of replication speed and origin firing depend on MK2-mediated signaling.


Assuntos
Replicação do DNA , Pontos de Checagem da Fase G2 do Ciclo Celular , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Antimetabólitos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem , Dano ao DNA , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/metabolismo , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Técnicas de Silenciamento de Genes , Histonas/genética , Histonas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Knockout , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Raios Ultravioleta , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Gencitabina
12.
J Med Entomol ; 52(1): 9-23, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26336275

RESUMO

The stages of decomposition and the faunal succession on rabbit carcasses in three different habitats, namely jungle, rural, and highland areas, were studied. Three New Zealand White rabbit (Oryctolagus cuniculus) carcasses weighing ∼2 kg were sampled daily until the decomposition process was completed. Representative specimens of adult flies, larvae, pupa, and mites were collected from the carcasses and processed in the laboratory. There were differences in decomposition rate and faunal succession between the carcasses. The fastest rate of decomposition was recorded in rural area, and the slowest rate of decomposition was recorded in highland area. The carcasses exhibited the same pattern of colonization by adult flies, but the dominant species of larvae and adult flies on each carcass in specific habitats were different. The primary species of flies recorded in jungle were Chrysomya megacephala F., Chrysomya rufifacies (Macquart), Chrysomya chani Kurahashi, Chrysomya villenuevi Patton, Chrysomya nigripes Aubertin, Chrysomya pinguis (Walker), Hemipyrellia ligurriens (Wiedemann), Hemipyrellia tagaliana (Bigot), Hypopyiopsis fumipennis (Walker), Hypopygiopsis violacea (Macquart), and Hydrotaea spinigera Stein represented by both adults and larvae. Musca domestica L., Atherigona sp., Lioproctia pattoni (Senior-White), Lioproctia saprianovae Pape & Bänziger, and Seniorwhitea princeps (Wiedemann) were represented by adults only. The biodiversity of flies in the rural area were C. megacephala, C. rufifacies, H. ligurriens, Fannia canicularis L., Hydrotaea chalcogaster (Wiedemann), and Hyd. spinigera represented by both adults and larvae, meanwhile M. domestica, Atherigona sp., Boettcherisca peregrina (Robineau-Desvoidy), Parasarcophaga taenionota Wiedemann, Parasarcophaga scopariiformis Senior-White, and S. princeps were represented by adults only. The species of flies collected in the highland area were Lucilia porphyrina (Walker), C. megacephala, C. rufifacies, C. villenuevi, C. pinguis, H. ligurriens, Hyd. spinigera, Hyd. chalcogaster, F. canicularis, and Boettcherisca highlandica Kurahashi & Tan represented by both adults and larvae, whereas C. nigripes, Chrysomya thanomthini Kurahashi & Tumrasvin, M. domestica, Atherigona sp., Parasarcophaga albiceps Meigen, P. taenionota, Sepsidae, Phoridae, and Millichidae were represented by adults only. Faunal succession followed the sequence of dominant flies, i.e., Calliphoridae, Sarcophagidae, Muscidae, Sepsidae, and lastly Stratiomyidae for jungle, or Sepsidae for rural and highland studies. Mites, from suborders Mesostigmata, Prostigmata, Astigmatina, and Oribatida, were also recovered throughout decomposition, which could be used for future implementation in forensic investigations. The data obtained from this study could provide more accurate indicators for local forensic scientists in solving criminal cases especially on the determination of time and primary location of death.


Assuntos
Ácaros e Carrapatos/fisiologia , Dípteros/fisiologia , Ecossistema , Patologia Legal/métodos , Ácaros e Carrapatos/crescimento & desenvolvimento , Animais , Cadáver , Dípteros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Malásia , Mudanças Depois da Morte , Pupa/crescimento & desenvolvimento , Pupa/fisiologia , Coelhos , Clima Tropical
13.
Biol Lett ; 10(9)2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25209198

RESUMO

Fossil mesostigmatid mites (Acari: Parasitiformes: Mesostigmata) are extremely rare, and specimens from only nine families, including four named species, have been described so far. A new record of Myrmozercon sp. described here from Eocene (ca 44-49 Myr) Baltic amber represents the first-and so far only-fossil example of the derived, extant family Laelapidae. Significantly, modern species of this genus are habitually myrmecophilous and the fossil mite described here is preserved attached to the head of the dolichoderine ant Ctenobethylus goepperti (Mayr, 1868). It thus offers the oldest unequivocal evidence for an ecological association between mesostigmatid mites and social insects in the order Hymenoptera.


Assuntos
Ácaros e Carrapatos/anatomia & histologia , Ácaros e Carrapatos/classificação , Âmbar , Formigas/parasitologia , Fósseis , Animais , Países Bálticos , Especificidade da Espécie
14.
J Public Health (Oxf) ; 36(3): 511-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24167199

RESUMO

BACKGROUND: UK clinical guidance for lung cancer (NICE 141) includes pathways for chest X-rays (CXRs). Many patients fulfilling the criteria do not receive one, either because they do not consult their doctor or because their doctor does not refer them. The town of Corby, UK, has particularly high incidence and mortality rates for lung cancer and was chosen as a pilot site for a new, patient-requested X-ray service. METHODS: The number of community-initiated CXRs were compared before and after the introduction of the service and between similar geographical areas. Clinical data and patient questionnaires were analysed for those attending the service. RESULTS: There was a 63% increase in the total number of community-initiated CXRs in Corby for the year following the introduction of the service, compared with the year before. This was statistically greater than in surrounding geographical areas. Corby General Practitioners also requested 47% more CXRs than in the previous year. CONCLUSIONS: The implementation of the service was associated with a significant increase in the numbers of clinically indicated CXRs in an area of high lung cancer incidence and mortality. The service attracted a clinically appropriate population. The numbers of cancers detected were in line with statistical expectations.


Assuntos
Acessibilidade aos Serviços de Saúde/organização & administração , Radiografia Torácica/estatística & dados numéricos , Doenças Respiratórias/diagnóstico por imagem , Instituições de Assistência Ambulatorial/organização & administração , Instituições de Assistência Ambulatorial/estatística & dados numéricos , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Radiografia Torácica/métodos , Inquéritos e Questionários , Reino Unido
15.
Pharmaceutics ; 16(5)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38794245

RESUMO

Antimicrobial peptides (AMPs) are important mediator molecules of the innate defense mechanisms in a wide range of living organisms, including bacteria, mammals, and plants. Among them, peptide protease inhibitors (PPIs) from plants play a central role in their defense mechanisms by directly attacking pathogens or by modulating the plant's defense response. The growing prevalence of microbial resistance to currently available antibiotics has intensified the interest concerning these molecules as novel antimicrobial agents. In this scenario, PPIs isolated from a variety of plants have shown potential in inhibiting the growth of pathogenic bacteria, protozoans, and fungal strains, either by interfering with essential biochemical or physiological processes or by altering the permeability of biological membranes of invading organisms. Moreover, these molecules are active inhibitors of a range of proteases, including aspartic, serine, and cysteine types, with some showing particular efficacy as trypsin and chymotrypsin inhibitors. In this review, we provide a comprehensive analysis of the potential of plant-derived PPIs as novel antimicrobial molecules, highlighting their broad-spectrum antimicrobial efficacy, specificity, and minimal toxicity. These natural compounds exhibit diverse mechanisms of action and often multifunctionality, positioning them as promising molecular scaffolds for developing new therapeutic antibacterial agents.

16.
Sci Data ; 11(1): 583, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834686

RESUMO

Mg/Ca is an independent proxy in paleoceanography to reconstruct past seawater temperature. Femtosecond Laser Ablation Inductively Coupled Plasma Mass Spectrometry (fs-LA-ICP-MS) was employed to determine the Mg/Ca composition of tests (shells) of the planktic foraminifer species Globigerinoides ruber albus (white chromotype) and G. ruber ruber (red/pink chromotype) sampled alive from the temperate to subtropical eastern North Atlantic with the research sailing yacht Eugen Seibold. Mg/Ca data are compared to (i) the measured in-situ temperature of ambient seawater, (ii) average mixed layer temperature, and (iii) sea surface temperature (SST). The pooled mean chamber Mg/Ca from each plankton tow site exhibits a positive relationship with SST. Two chamber-specific calibrations are derived, which are consistent with previous calibration equations for comparable paleo-archives. The results confirm fs-LA-ICP-MS as reliable method for determining Mg/Ca in G. ruber, and both the penultimate and antepenultimate chambers of adult specimens may provide comprehensible Mg/Ca temperatures of the surface ocean.


Assuntos
Cálcio , Foraminíferos , Magnésio , Espectrometria de Massas , Água do Mar , Magnésio/análise , Água do Mar/análise , Cálcio/análise , Espectrometria de Massas/métodos , Calibragem , Temperatura
17.
Zootaxa ; 3691: 301-23, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26167587

RESUMO

The Sejoidea currently contains three families (Sejidae, Ichthyostomatogasteridae, Uropodellidae) of enigmatic mesostigmatic mites with a mixture of characters of general distribution in the Parasitiformes (e.g., hypertrichy, tarsus IV with an intercalary sclerite bearing a pair of ventral setae, archispermous mating system) and derived character states both unique (e.g., distinctive female sterno-gential region; first hypostomal setae adjacent and more or less membranous) and apparently convergent with other Mesostigmata (e.g., 2-tined palpal apotele, reduced dorsal sclerotisation in the adult, phoretic deutonymph). In this paper, I review the characters defining the Sejoidea; propose a new genus, Reginacharlottia gen. nov. based on two new species: one from Lord Howe Island, New South Wales, Australia (R. lordhowensis sp. nov.) and one from Bahia State, Brazil (R. braziliensis sp. nov.) and erect a new family, Reginacharlottiidae fam. nov. to accommodate them. These new species share a number of unusual characters not otherwise known in the Sejida, including a plumose interdigital cheliceral excrescence, a highly reduced female genital shield, and a highly modified anal region covered by a pair of hypertrophied preanal setae; the postanal seta is absent. Adult female R. lordhowensis carry up to a dozen eggs that enclose fully developed larvae; the larvae also lack the postanal seta, but have a unique pygidial tubercle that may act as an egg burster. In addition, the female of Sejus americanus (Banks, 1902) is redescribed and the male described for the first time. Sejus species tend to be more typical of the warmer parts of the world, but S. americanus extends well into the boreal forest of Alberta, Canada (56 degrees N). A key to separate the families of Sejoidea is provided.


Assuntos
Ácaros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Feminino , Ilhas , Masculino , Ácaros/anatomia & histologia , Ácaros/crescimento & desenvolvimento , Tamanho do Órgão
18.
Zootaxa ; 3620: 483-99, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26120720

RESUMO

The oribatid mite genus Protoribates Berlese (Haplozetidae) is reviewed for North America and the genus diagnosis is revised to account for the North American species, Protoribates robustior (Jacot, 1937) is redescribed and newly reported from western North America and a new species from Alberta is described. Protoribates haughlandae sp. n. is bisexual, heterotridactylous, and lives primarily in the peat soils of fens and bogs. Protoribates robustior is all-female, monodactylous, and occurs primarily in dry forests or in dry, treeless sites dominated by grasses, sedges, and shrubs. Both species feed on fungal hyphae and spores, but P. haughlandae also is an opportunistic predator and/or necrophage of small arthropods and P. robustior gut contents often include material that resembles plant cell walls. Examination of type specimens confirms that Protoribates prionotus (Woolley, 1968) is a junior synonym of the widespread Protoribates lophotrichus (Berlese, 1904). A key to differentiate Lagenobates from Protoribates and to identify the 7 species of the latter that are known or reported from North America is provided.


Assuntos
Ácaros e Carrapatos/classificação , Ácaros e Carrapatos/fisiologia , Ácaros e Carrapatos/crescimento & desenvolvimento , Ácaros e Carrapatos/ultraestrutura , Alberta , Distribuição Animal , Animais , Ecossistema , Comportamento Alimentar , Feminino , Masculino , Microscopia Eletrônica de Varredura
19.
Zootaxa ; 3741: 459-89, 2013 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-25113002

RESUMO

Species in the oribatid mite genus Tectoribates are primarily Palaearctic and Neotropical, with scattered, unidentified records from North America. Herein, we describe 3 new Tectoribates species from dry forest and prairie habitats in North America: T. alcecampestris sp. nov., from Alberta, T. borealis sp. nov., from southern Alberta and Ontario, both on the basis of adults and nymphs, and T. campestris sp. nov., from dry grassland habitats in Ontario and Kansas, on the basis of adults. We provide a revised and expanded diagnosis for adults of Tectoribates. We assess relationships of Tectoribates, using characters of adults and newly discovered apheredermous, plicate immatures. We include observations on Pseudotectoribates which is closely related to Tectoribates. The closest relatives of these genera are hypothesised to be among the Tegoribatidae (Achipterioidea) rather than among the Achipteriidae (Achipterioidea), Oribatellidae (Oribatelloidea), or Ceratozetoidea, as suggested in previous classifications. Finally, we give a key to adults of the world fauna of Tectoribates.


Assuntos
Ácaros/classificação , Animais , Canadá , Ecossistema , Feminino , Ácaros/anatomia & histologia , Ninfa , Filogenia , Estados Unidos
20.
Pharmaceutics ; 15(3)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36986642

RESUMO

Fungal infections are a growing public health concern worldwide and the emergence of antifungal resistance has limited the number of therapeutic options. Therefore, developing novel strategies for identifying and developing new antifungal compounds is an active area of research in the pharmaceutical industry. In this study, we purified and characterized a trypsin protease inhibitor obtained from Yellow Bell Pepper (Capsicum annuum L.) seeds. The inhibitor not only showed potent and specific activity against the pathogenic fungus Candida albicans, but was also found to be non-toxic against human cells. Furthermore, this inhibitor is unique in that it also inhibits α-1,4-glucosidase, positioning it as one of the first plant-derived protease inhibitors with dual biological activity. This exciting discovery opens new avenues for the development of this inhibitor as a promising antifungal agent and highlights the potential of plant-derived protease inhibitors as a rich source for the discovery of novel multifunctional bioactive molecules.

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