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1.
iScience ; 27(3): 109006, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38361610

RESUMO

Many vaccines, including those using recombinant antigen subunits, rely on adjuvant(s) to enhance the efficacy of the host immune responses. Among the few adjuvants clinically approved, QS-21, a saponin-based immunomodulatory molecule isolated from the tree bark of Quillaja saponaria (QS) is used in complex formulations in approved effective vaccines. High demand of the QS raw material as well as manufacturing scalability limitation has been barriers here. We report for the first-time successful plant cell culture production of QS-21 having structural, chemical, and biologic, properties similar to the bark extracted product. These data ensure QS-21 and related saponins are broadly available and accessible to drug developers.

2.
Evol Anthropol ; 33(2): e22018, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38217397

RESUMO

An uncritical reliance on the phylogenetic species concept has led paleoanthropologists to become increasingly typological in their delimitation of new species in the hominin fossil record. As a practical matter, this approach identifies species as diagnosably distinct groups of fossils that share a unique suite of morphological characters but, ontologically, a species is a metapopulation lineage segment that extends from initial divergence to eventual extinction or subsequent speciation. Working from first principles of species concept theory, it is clear that a reliance on morphological diagnosabilty will systematically overestimate species diversity in the fossil record; because morphology can evolve within a lineage segment, it follows that early and late populations of the same species can be diagnosably distinct from each other. We suggest that a combination of morphology and chronology provides a more robust test of the single-species null hypothesis than morphology alone.


Assuntos
Hominidae , Animais , Hominidae/anatomia & histologia , Filogenia , Evolução Biológica , Fósseis
3.
Health Mark Q ; 41(1): 71-94, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38019606

RESUMO

The objective of this study was to determine the factors influencing consumer intention to donate blood in an emerging market setting. A quantitative research design was followed that entailed the collection of data from 308 non-donor respondents, using a self-administered online questionnaire. The conceptual model and hypotheses were analysed statistically, using SPSS to conduct reliability analysis, correlation analysis, and multiple regression analysis. The findings revealed that awareness of consequences, ascription of responsibility, and personal norms had a positive and significant influence on consumers' intention to donate blood. Ascription of responsibility was the largest influencer of personal norms towards blood donation.


Assuntos
Comportamento do Consumidor , Intenção , Humanos , Reprodutibilidade dos Testes , África do Sul , Inquéritos e Questionários
4.
JOR Spine ; 6(4): e1293, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38156055

RESUMO

Background: Intervertebral disc (IVD) disorders (e.g., herniation) directly contribute to back pain, which is a leading cause of global disability. Next-generation treatments for IVD herniation need advanced preclinical testing to evaluate their ability to repair large defects, prevent reherniation, and limit progressive degeneration. This study tested whether experimental, injectable, and nonbioactive biomaterials could slow IVD degeneration in an ovine discectomy model. Methods: Ten skeletally mature sheep (4-5.5 years) experienced partial discectomy injury with cruciate-style annulus fibrosus (AF) defects and 0.1 g nucleus pulposus (NP) removal in the L1-L2, L2-L3, and L3-L4 lumbar IVDs. L4-L5 IVDs were Intact controls. IVD injury levels received: (1) no treatment (Injury), (2) poly (ethylene glycol) diacrylate (PEGDA), (3) genipin-crosslinked fibrin (FibGen), (4) carboxymethylcellulose-methylcellulose (C-MC), or (5) C-MC and FibGen (FibGen + C-MC). Animals healed for 12 weeks, then IVDs were assessed using computed tomography (CT), magnetic resonance (MR) imaging, and histopathology. Results: All repaired IVDs retained ~90% of their preoperative disc height and showed minor degenerative changes by Pfirrmann grading. All repairs had similar disc height loss and Pfirrmann grade as Injury IVDs. Adhesive AF sealants (i.e., PEGDA and FibGen) did not herniate, although repair caused local endplate (EP) changes and inflammation. NP repair biomaterials (i.e., C-MC) and combination repair (i.e., FibGen + C-MC) exhibited lower levels of degeneration, less EP damage, and less severe inflammation; however, C-MC showed signs of herniation via biomaterial expulsion. Conclusions: All repair IVDs were noninferior to Injury IVDs by IVD height loss and Pfirrmann grade. C-MC and FibGen + C-MC IVDs had the best outcomes, and may be appropriate for enhancement with bioactive factors (e.g., cells, growth factors, and miRNAs). Such bioactive factors appear to be necessary to prevent injury-induced IVD degeneration. Application of AF sealants alone (i.e., PEGDA and FibGen) resulted in EP damage and inflammation, particularly for PEGDA IVDs, suggesting further material refinements are needed.

6.
J Vasc Interv Radiol ; 34(8): 1359-1363, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37030423

RESUMO

This retrospective single-center study evaluated the change in required dosage of acetazolamide and topiramate before and after dural venous sinus stent placement (VSSP) for idiopathic intracranial hypertension (IIH). Adults diagnosed with IIH who failed optimized medical management and were treated with VSSP were included. This study comprised 55 patients who underwent VSSP for the diagnosis of IIH. The median preprocedural dosage of acetazolamide and topiramate was 1,000 mg (range, 500-4,000 mg) and 100 mg (range, 0-200 mg), respectively, among patients able to tolerate the medications. The median postprocedural dosage of acetazolamide and topiramate was 375 mg (range, 0-4,000 mg), with a mean reduction of 52.9% (P = .001), and 0 mg (range, 0-200 mg), with a mean reduction of 45.9% (P = .005), respectively. Dural VSSP significantly reduced dosage requirements for acetazolamide and/or topiramate, potentially reducing the morbidity secondary to medication side effects.


Assuntos
Inibidores da Anidrase Carbônica , Pseudotumor Cerebral , Adulto , Humanos , Inibidores da Anidrase Carbônica/efeitos adversos , Pseudotumor Cerebral/diagnóstico por imagem , Pseudotumor Cerebral/tratamento farmacológico , Pseudotumor Cerebral/complicações , Acetazolamida/efeitos adversos , Estudos Retrospectivos , Topiramato/efeitos adversos , Stents
7.
Sci Adv ; 8(42): eabp9767, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36269821

RESUMO

The frontal sinuses are cavities inside the frontal bone located at the junction between the face and the cranial vault and close to the brain. Despite a long history of study, understanding of their origin and variation through evolution is limited. This work compares most hominin species' holotypes and other key individuals with extant hominids. It provides a unique and valuable perspective of the variation in sinuses position, shape, and dimensions based on a simple and reproducible methodology. We also observed a covariation between the size and shape of the sinuses and the underlying frontal lobes in hominin species from at least the appearance of Homo erectus. Our results additionally undermine hypotheses stating that hominin frontal sinuses were directly affected by biomechanical constraints resulting from either chewing or adaptation to climate. Last, we demonstrate their substantial potential for discussions of the evolutionary relationships between hominin species.


Assuntos
Fósseis , Hominidae , Animais , Humanos , Crânio/anatomia & histologia , Encéfalo , Clima
9.
Nat Ecol Evol ; 5(1): 38-45, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33168991

RESUMO

Paranthropus robustus is a small-brained extinct hominin from South Africa characterized by derived, robust craniodental morphology. The most complete known skull of this species is DNH 7 from Drimolen Main Quarry, which differs from P. robustus specimens recovered elsewhere in ways attributed to sexual dimorphism. Here, we describe a new fossil specimen from Drimolen Main Quarry, dated from approximately 2.04-1.95 million years ago, that challenges this view. DNH 155 is a well-preserved adult male cranium that shares with DNH 7 a suite of primitive and derived features unlike those seen in adult P. robustus specimens from other chronologically younger deposits. This refutes existing hypotheses linking sexual dimorphism, ontogeny and social behaviour within this taxon, and clarifies hypotheses concerning hominin phylogeny. We document small-scale morphological changes in P. robustus associated with ecological change within a short time frame and restricted geography. This represents the most highly resolved evidence yet of microevolutionary change within an early hominin species.


Assuntos
Hominidae , Animais , Fósseis , Masculino , Filogenia , Crânio , África do Sul
10.
Science ; 368(6486)2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32241925

RESUMO

Understanding the extinction of Australopithecus and origins of Paranthropus and Homo in South Africa has been hampered by the perceived complex geological context of hominin fossils, poor chronological resolution, and a lack of well-preserved early Homo specimens. We describe, date, and contextualize the discovery of two hominin crania from Drimolen Main Quarry in South Africa. At ~2.04 million to 1.95 million years old, DNH 152 represents the earliest definitive occurrence of Paranthropus robustus, and DNH 134 represents the earliest occurrence of a cranium with clear affinities to Homo erectus These crania also show that Homo, Paranthropus, and Australopithecus were contemporaneous at ~2 million years ago. This high taxonomic diversity is also reflected in non-hominin species and provides evidence of endemic evolution and dispersal during a period of climatic variability.


Assuntos
Evolução Biológica , Extinção Biológica , Hominidae/anatomia & histologia , Hominidae/classificação , Animais , Cavernas , Classificação , Humanos , Crânio , África do Sul
11.
Genet Med ; 22(1): 160-169, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31316169

RESUMO

PURPOSE: To evaluate the frequency and clinical impact of switches in antiplatelet therapy following implementation of CYP2C19 genotyping after percutaneous coronary intervention (PCI). METHODS: The frequency of escalation (clopidogrel switched to prasugrel/ticagrelor) and de-escalation (prasugrel/ticagrelor switched to clopidogrel) was evaluated in 1063 PCI patients who underwent CYP2C19 genotyping. Risk of major adverse cardiovascular or cerebrovascular (MACCE) and bleeding events over one year was evaluated. RESULTS: Antiplatelet therapy switches were common (19%), with escalation (101/115: 88%) and de-escalation (77/84: 92%) occurring predominantly in patients with and without a CYP2C19 nonfunctional allele, respectively. Nonfunctional allele carriers initiated and continued on clopidogrel had a significantly higher risk of experiencing either a MACCE or bleeding event compared with those escalated to prasugrel/ticagrelor (52 vs. 19 events/100 patient-years; adjusted hazard ratio [HR] 2.89 [1.44-6.13], p = 0.003). Patients without a nonfunctional allele de-escalated to clopidogrel had no difference in risk compared with those initiated and continued on prasugrel/ticagrelor (21 vs. 19 events/100 patient-years; adjusted HR 1.13 [0.51-2.34], p = 0.751). CONCLUSION: CYP2C19-guided escalation and de-escalation is common in a real-world setting. Continuation of clopidogrel in nonfunctional allele carriers is associated with adverse outcomes. De-escalation to clopidogrel in patients without a nonfunctional allele appears safe and warrants prospective study.


Assuntos
Clopidogrel/administração & dosagem , Oclusão Coronária/terapia , Citocromo P-450 CYP2C19/genética , Inibidores da Agregação Plaquetária/administração & dosagem , Cloridrato de Prasugrel/administração & dosagem , Ticlopidina/administração & dosagem , Idoso , Clopidogrel/efeitos adversos , Oclusão Coronária/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea , Inibidores da Agregação Plaquetária/efeitos adversos , Cloridrato de Prasugrel/efeitos adversos , Medicina de Precisão , Estudos Prospectivos , Ticlopidina/efeitos adversos , Resultado do Tratamento
13.
Cureus ; 10(9): e3337, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30473970

RESUMO

The number of minimally invasive interventional radiology (IR) and interventional cardiology vascular procedures performed increases every year. As the number of vascular procedures increases, the need for advanced technology and innovative devices increases as well. Traditionally, as a general rule, a catheter is used in conjunction with a guidewire in such procedures. The underlying principle of IR is to always use a guidewire prior to any advancement of a catheter. This article describes a revolutionary theory that utilizes a new technology and contradicts this basic principle. Using a steerable microcatheter, a bilateral uterine artery embolization was performed from a wrist access with no guidewire. Furthermore, this technique reduced the procedure time by more than half when compared to standard of care. This technique may be applicable to other IR procedures, which could potentially reduce the time critically ill patients spend in the procedure area outside the intensive care unit.

14.
Cureus ; 10(9): e3251, 2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-30416902

RESUMO

Significant incidental findings reported on computed tomography (CT) scans are common. This article describes a 72-year-old man evaluated for possible bowel obstruction in whom was found a 3.1-cm x 2.6-cm centrally located enhancing mass in the left kidney highly suspicious for renal cell carcinoma. Due to substantial medical comorbidities, the patient was deemed a poor surgical candidate for either partial or complete nephrectomy. Interventional radiology was consulted for a minimally invasive ablation procedure. The large size and central location of the tumor involving the renal collecting system initially precluded definitive percutaneous cryoablation. Intra-arterial embolization was used as neoadjuvant therapy to decrease tumor burden. Fluoroscopy-guided bland embolization was performed targeting the arterial supply of the mass until stagnation of flow was achieved. A subsequent two-month post-embolization follow-up CT scan showed a 30% reduction in tumor size. Shrinkage of the mass from a central to a more peripheral location allowed for a cryoablation approach that would avoid damage to the vulnerable collecting system. Cryoablation was performed, and intraoperative CT demonstrated complete coverage of the tumor by the ice ball with no damage to the renal collecting system. A follow-up CT scan four years later showed no residual malignancy at the ablation site.

15.
Biomacromolecules ; 15(10): 3503-10, 2014 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-24941228

RESUMO

The fabrication of de novo proteins able to self-assemble on the nano- to meso-length scales is critical in the development of protein-based biomaterials in nanotechnology and medicine. Here we report the design and characterization of a protein engineered coiled-coil that not only assembles into microfibers, but also can bind hydrophobic small molecules. Under ambient conditions, the protein forms fibers with nanoscale structure possessing large aspect ratios formed by bundles of α-helical homopentameric assemblies, which further assemble into mesoscale fibers in the presence of curcumin through aggregation. Surprisingly, these biosynthesized fibers are able to form in conditions of remarkably low concentrations. Unlike previously designed coiled-coil fibers, these engineered protein microfibers can bind the small molecule curcumin throughout the assembly, serving as a depot for encapsulation and delivery of other chemical agents within protein-based 3D microenvironments.


Assuntos
Proteínas/química , Sequência de Aminoácidos , Dados de Sequência Molecular , Nanotecnologia/métodos , Conformação Proteica , Engenharia de Proteínas/métodos , Estrutura Secundária de Proteína
16.
Obesity (Silver Spring) ; 19(12): 2316-21, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21633398

RESUMO

The regulation of energy intake is a complex process involving the integration of homeostatic signals and both internal and external sensory inputs. To better understand the neurobiology of this process and how it may be dysfunctional in obesity, this study examined activity of the brain's "default network" in reduced-obese (RO) as compared to lean individuals. The default network is a group of functionally connected brain regions thought to play an important role in internally directed cognitive activity and the interplay between external and internal sensory processing. Functional magnetic resonance imaging was performed in 24 lean and 18 RO individuals in the fasted state after 2 days of eucaloric energy intake and after 2 days of 30% overfeeding in a counterbalanced design. Scanning was performed while subjects passively viewed images of food and nonfood objects. Independent component analysis was used to identify the default network component. In the eucaloric state, greater default network activity was observed in RO compared to lean individuals in the lateral inferior parietal and posterior cingulate cortices. Activity was positively correlated with appetite. Overfeeding resulted in increased default network activity in lean but not RO individuals. These findings suggest that the function of the default network, a major contributor to intrinsic neuronal activity, is altered in obesity and/or obese-prone individuals. Future studies of the network's function and its relationship to other brain networks may improve our understanding of the mechanisms and treatment of obesity.


Assuntos
Regulação do Apetite/fisiologia , Encéfalo/fisiopatologia , Sinais (Psicologia) , Ingestão de Energia/fisiologia , Vias Neurais/fisiologia , Estado Nutricional/fisiologia , Obesidade/fisiopatologia , Adulto , Mapeamento Encefálico/métodos , Estudos Cross-Over , Jejum , Feminino , Alimentos , Humanos , Hiperfagia , Imageamento por Ressonância Magnética , Masculino , Obesidade/psicologia , Estimulação Luminosa , Sensação/fisiologia , Magreza , Redução de Peso
17.
Psychopharmacology (Berl) ; 216(2): 287-95, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21331518

RESUMO

RATIONALE: The default mode network (DMN), one of several resting-state networks (RSN) in the brain, is thought to be involved in self-referential thought, awareness, and episodic memories. Nicotine improves cognitive performance, in part by improving attention. Nicotinic agonists have been shown to decrease activity in regions within DMN and increase activity in regions involved in visual attention during effortful processing of external stimuli. It is unknown if these pharmacological effects also occur in the absence of effortful processing. OBJECTIVES: This study aims to determine if nicotine suppresses activity in default mode and enhances activity in extra-striate RSNs in the absence of an external visual task. METHODS: Within-subject, single-blinded, counterbalanced study of 19 non-smoking subjects who had resting functional MRI scans after 7 mg nicotine or placebo patch. Group independent component analysis was performed. The DMN component was identified by spatial correlation with a reference DMN mask. A visual attention component was identified by spatial correlation with an extra-striate mask. Analyses were conducted using statistical parametric mapping. RESULTS: Nicotine was associated with decreased activity in regions within the DMN and increased activity in extra-striate regions. CONCLUSIONS: Suppression of DMN and enhancement of extra-striate resting-state activity in the absence of visual stimuli or effortful processing suggest that nicotine's cognitive effects may involve a shift in activity from networks that process internal to those that process external information. This is a potential mechanism by which cholinergic agonists may have a beneficial effect in diseases associated with altered resting-state activity.


Assuntos
Rede Nervosa/efeitos dos fármacos , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Adulto , Mapeamento Encefálico , Estudos Cross-Over , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Rede Nervosa/metabolismo , Método Simples-Cego , Percepção Visual
18.
Curr Biol ; 21(2): 97-105, 2011 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-21215634

RESUMO

BACKGROUND: Synaptic transmission can occur in a binary or graded fashion, depending on whether transmitter release is triggered by action potentials or by gradual changes in membrane potential. Molecular differences of these two types of fusion events and their differential regulation in a physiological context have yet to be addressed. Complexin is a conserved SNARE-binding protein that has been proposed to regulate both spontaneous and stimulus-evoked synaptic vesicle (SV) fusion. RESULTS: Here we examine complexin function at a graded synapse in C. elegans. Null complexin (cpx-1) mutants are viable, although nervous system function is significantly impaired. Loss of CPX-1 results in a 3-fold increase in the rate of tonic synaptic transmission at the neuromuscular junction, whereas stimulus-evoked SV fusion is decreased 10-fold. A truncated CPX-1 missing its C-terminal domain can rescue stimulus-evoked synaptic vesicle exocytosis but fails to suppress tonic activity, demonstrating that these two modes of exocytosis can be distinguished at the molecular level. A CPX-1 variant with impaired SNARE binding also rescues evoked, but not tonic, neurotransmitter release. Finally, tonic, but not evoked, release can be rescued in a syntaxin point mutant by removing CPX-1. Rescue of either form of exocytosis partially restores locomotory behavior, indicating that both types of synaptic transmission are relevant. CONCLUSION: These observations suggest a dual role for CPX-1: suppressing SV exocytosis, driven by low levels of endogenous neural activity, while promoting synchronous fusion of SVs driven by a depolarizing stimulus. Thus, patterns of synaptic activity regulate complexin's inhibitory and permissive roles at a graded synapse.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/citologia , Proteínas do Tecido Nervoso/metabolismo , Vesículas Sinápticas/fisiologia , Proteínas Adaptadoras de Transporte Vesicular/genética , Sequência de Aminoácidos , Animais , Comportamento Animal , Proteínas de Caenorhabditis elegans/genética , Potenciais Evocados/fisiologia , Regulação da Expressão Gênica/fisiologia , Dados de Sequência Molecular , Mutação , Proteínas do Tecido Nervoso/genética
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