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1.
Subst Use Misuse ; 58(11): 1360-1366, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37331982

RESUMEN

Background: People experiencing substance use disorders (SUD) face myriad challenges in maintaining changes in substance use after treatment. Mobile phones can play a role in supporting the recovery process. To date, research has not explored how individuals use mobile phones to seek social support as they enter SUD recovery. Objectives: We sought to understand how individuals in SUD treatment use mobile technology in support of their recovery. Methods: We conducted semi-structured interviews with thirty individuals in treatment for any SUD in northeastern Georgia and southcentral Connecticut. Interviews explored participants' attitudes toward mobile technology and how they used mobile technology while using substances, in treatment, and in recovery. Qualitative data were coded and analyzed using thematic analysis. Results: We identified three major themes related to how participants: (1) adapted their use of mobile technology as they entered recovery, (2) relied on mobile technology for social support while in recovery, while (3) some found aspects of mobile technology triggering. Many individuals in SUD treatment reported using mobile phones to buy or sell drugs; as such, they took measures to adapt their use of mobile technology as they changed substance use behaviors. As they entered recovery, individuals relied on mobile phones for affiliational, emotional, informational, and instrumental support, though some did share they found some aspects of mobile phones triggering. Conclusion: These findings highlight the importance of treatment providers engaging in conversations around mobile phone use to help individuals avoid triggers and connect with social supports. These findings uncover new opportunities for recovery support interventions utilizing mobile phones as a delivery mechanism.


Asunto(s)
Teléfono Celular , Trastornos Relacionados con Sustancias , Humanos , Trastornos Relacionados con Sustancias/terapia , Apoyo Social , Actitud , Connecticut
2.
Georgian Med News ; (333): 6-12, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36780614

RESUMEN

Following increased cultural awareness, expanded access to care, and decreased stigmatization, the number of transgender individuals seeking gender affirmation surgery such as gender-affirmation mastectomy (GAM) continues to rise. While post-mastectomy breast tissue is often sent for pathologic evaluation, few studies address the utility and standardization of this practice. This literature review evaluates the pathology findings in GAM specimens reported in the medical literature. A systematic review following PRISMA guidelines was performed to evaluate all medical publications related to pathology reports following GAM. The overall type and incidence of benign and malignant breast lesions were analyzed to elucidate which patient characteristics significantly affect the pathology findings. Overall, eight of 488 identified studies met inclusion criteria (1278 patients). The incidence of pre-malignant lesions was 2.42%, including flat epithelial atypia (0.08%), atypical hyperplasia (0.23%), atypical ductal hyperplasia (1.33%), atypical lobular hyperplasia (0.39%), and lobular carcinoma in situ (0.39%).Patient age, hormonal therapy, and family / patient history of breast cancer were inconsistently reported among included studies. Lack of standardized pathologic classification did not permit further statistical analysis. Although patients who undergo GAM are unlikely to have premalignant or malignant findings on breast pathology examination, pathologic evaluation of breast tissue remains common practice. Additional studies, which include a standardized method of pathologic evaluation, are necessary before practice guidelines can be recommended.


Asunto(s)
Neoplasias de la Mama , Carcinoma in Situ , Carcinoma Intraductal no Infiltrante , Lesiones Precancerosas , Humanos , Femenino , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/patología , Mastectomía , Hiperplasia , Carcinoma Intraductal no Infiltrante/epidemiología , Carcinoma Intraductal no Infiltrante/patología , Carcinoma Intraductal no Infiltrante/cirugía , Carcinoma in Situ/epidemiología , Carcinoma in Situ/patología , Carcinoma in Situ/cirugía , Lesiones Precancerosas/patología
3.
BMC Genomics ; 22(1): 906, 2021 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-34922464

RESUMEN

BACKGROUND: Disruption of alveolar epithelial cell (AEC) differentiation is implicated in distal lung diseases such as chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, and lung adenocarcinoma that impact morbidity and mortality worldwide. Elucidating underlying disease pathogenesis requires a mechanistic molecular understanding of AEC differentiation. Previous studies have focused on changes of individual transcription factors, and to date no study has comprehensively characterized the dynamic, global epigenomic alterations that facilitate this critical differentiation process in humans. RESULTS: We comprehensively profiled the epigenomic states of human AECs during type 2 to type 1-like cell differentiation, including the methylome and chromatin functional domains, and integrated this with transcriptome-wide RNA expression data. Enhancer regions were drastically altered during AEC differentiation. Transcription factor binding analysis within enhancer regions revealed diverse interactive networks with enrichment for many transcription factors, including NKX2-1 and FOXA family members, as well as transcription factors with less well characterized roles in AEC differentiation, such as members of the MEF2, TEAD, and AP1 families. Additionally, associations among transcription factors changed during differentiation, implicating a complex network of heterotrimeric complex switching in driving differentiation. Integration of AEC enhancer states with the catalog of enhancer elements in the Roadmap Epigenomics Mapping Consortium and Encyclopedia of DNA Elements (ENCODE) revealed that AECs have similar epigenomic structures to other profiled epithelial cell types, including human mammary epithelial cells (HMECs), with NKX2-1 serving as a distinguishing feature of distal lung differentiation. CONCLUSIONS: Enhancer regions are hotspots of epigenomic alteration that regulate AEC differentiation. Furthermore, the differentiation process is regulated by dynamic networks of transcription factors acting in concert, rather than individually. These findings provide a roadmap for understanding the relationship between disruption of the epigenetic state during AEC differentiation and development of lung diseases that may be therapeutically amenable.


Asunto(s)
Epigenómica , Factores de Transcripción , Diferenciación Celular/genética , Epigénesis Genética , Humanos , Pulmón , Factores de Transcripción/genética
4.
J Anat ; 229(4): 560-7, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27296623

RESUMEN

Hyperostosis, excessive bone growth along bone that stems from bone, periosteum or articular or epiphyseal cartilage, occurs in at least 22 families of fishes most of which are tropical or subtropical marine species. While the presence of hyperostosis is well documented in fishes, the mechanism driving the development of the excessive bone growth is unclear. This study documented hyperostosis along the dorsal pterygiophores in both sexes of oarfish, Regalecus russellii; however, it was not present in all specimens examined. This is the second lampridiform fish with hyperostoses and the first case documented in a deeper-water, epi-mesopelagic fish. In oarfish, the majority of the dorsal pterygiophores tissues are poorly mineralized, anosteocytic bones with some fish displaying localized stiffened, hyperostotic growths near the distal edge. Oarfish lack a swim bladder so they must continuously beat their bi-directional dorsal fin to maintain position within the water column while engaged in locomotory behavior. These fishes have areas of localized, hyperostotic skeletal elements along the dorsal pterygiophores that, presumably, function as a stiffened lever system to support fin undulation. It was noted that hyperossification was not present in all fish examined and was only documented in fish with total lengths greater than 3 m.


Asunto(s)
Huesos/anatomía & histología , Peces/anatomía & histología , Animales , Femenino , Masculino , Tomografía Computarizada por Rayos X
6.
Integr Org Biol ; 5(1): obad032, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37818205

RESUMEN

Figures: Cory cat panel figureDrawing of bite force measuring equipment and indentation rig Pygocentrus nattereri jaw muscle morphology and skull anatomyBox plot grid of number of Pygocentrus nattereri bites before puncture along different body regions of Corydoras trilineatus during feeding trials resultsDrawing of color-coded Corydoras trilineatus with attack frequencies and average bites until puncture by Pygocentrus nattereriBox plot of average voluntary juvenile Pygocentrus nattereri bite forces to standard lengthPanel of linear ordinary least-squares regressions of Pygocentrus nattereri bite force to adductor mandibulae mass, standard length, and body massOrdinary least-squares regressions of voluntary bites to restrained bites of Pygocentrus nattereriPanel of indentation tests for intact and removed Corydoras trilineatus scutesPanel of indentation tests for Corydoras trilineatus body region. Synopsis: There is an evolutionary arms race between predators and prey. In aquatic environments, predatory fishes often use sharp teeth, powerful bites, and/or streamlined bodies to help capture their prey quickly and efficiently. Conversely, prey are often equipped with antipredator adaptations including: scaly armor, sharp spines, and/or toxic secretions. This study focused on the predator-prey interactions between the armored threestripe cory catfish (Corydoras trilineatus) and juvenile red-bellied piranha (Pygocentrus nattereri). Specifically, we investigated how resistant cory catfish armor is to a range of natural and theoretical piranha bite forces and how often this protection translated to survival from predator attacks by Corydoras. We measured the bite force and jaw functional morphology of P. nattereri, the puncture resistance of defensive scutes in C. trilineatus, and the in situ predatory interactions between the two. The adductor mandibulae muscle in juvenile P. nattereri is robust and delivers an average bite force of 1.03 N and maximum bite force of 9.71 N, yet its prey, C. trilineatus, survived 37% of confirmed bites without any damage. The C. trilineatus armor withstood an average of nine bites before puncture by P. nattereri. Predation was successful only when piranhas bit unarmored areas of the body, at the opercular opening and at the caudal peduncle. This study used an integrative approach to understand the outcomes of predator-prey interactions by evaluating the link between morphology and feeding behavior. We found that juvenile P. nattereri rarely used a maximal bite force and displayed a net predation success rate on par with other adult vertebrates. Conversely, C. trilineatus successfully avoided predation by orienting predator attacks toward their resilient, axial armor and behavioral strategies that reduced the predator's ability to bite in less armored regions of the body.

7.
J Morphol ; 284(4): e21574, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36807194

RESUMEN

Filter-feeding has been present for hundreds of millions of years, independently evolving in aquatic vertebrates' numerous times. Mysticete whales are a group of gigantic, marine filter-feeders that are defined by their fringed baleen and are divided into two groups: balaenids and rorquals. Recent studies have shown that balaenids likely feed using a self-cleaning, cross-flow filtration mechanism where food particles are collected and then swept to the esophagus for swallowing. However, it is unclear how filtering is achieved in the rorquals (Balaenopteridae). Lunging rorqual whales engulf enormous masses of both prey and water; the prey is then separated from the water through baleen plates lining the length of their upper jaw and positioned perpendicular to flow. Rorqual baleen is composed of both major (larger) and minor (smaller) keratin plates containing embedded fringe that extends into the whale's mouth, forming a filtering fringe. We used a multimodal approach, including microcomputed tomography (µCT) and scanning electron microscopy (SEM), to visualize and describe the variability in baleen anatomy across five species of rorqual whales, spanning two orders of magnitude in body length. For most morphological measurements, larger whales exhibited hypoallometry relative to body length. µCT and SEM revealed that the major and minor plates break away from the mineralized fringes at variable distances from the gums. We proposed a model for estimating the effective pore size to determine whether flow scales with body length or prey size across species. We found that pore size is likely not a proxy for prey size but instead, may reflect changes in resistance through the filter that affect fluid flow.


Asunto(s)
Conducta Alimentaria , Boca , Animales , Microtomografía por Rayos X , Boca/anatomía & histología , Ballenas/anatomía & histología , Maxilares/anatomía & histología
8.
Nat Commun ; 13(1): 1675, 2022 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-35354815

RESUMEN

The epidemiology of infectious causes of meningitis in sub-Saharan Africa is not well understood, and a common cause of meningitis in this region, Mycobacterium tuberculosis (TB), is notoriously hard to diagnose. Here we show that integrating cerebrospinal fluid (CSF) metagenomic next-generation sequencing (mNGS) with a host gene expression-based machine learning classifier (MLC) enhances diagnostic accuracy for TB meningitis (TBM) and its mimics. 368 HIV-infected Ugandan adults with subacute meningitis were prospectively enrolled. Total RNA and DNA CSF mNGS libraries were sequenced to identify meningitis pathogens. In parallel, a CSF host transcriptomic MLC to distinguish between TBM and other infections was trained and then evaluated in a blinded fashion on an independent dataset. mNGS identifies an array of infectious TBM mimics (and co-infections), including emerging, treatable, and vaccine-preventable pathogens including Wesselsbron virus, Toxoplasma gondii, Streptococcus pneumoniae, Nocardia brasiliensis, measles virus and cytomegalovirus. By leveraging the specificity of mNGS and the sensitivity of an MLC created from CSF host transcriptomes, the combined assay has high sensitivity (88.9%) and specificity (86.7%) for the detection of TBM and its many mimics. Furthermore, we achieve comparable combined assay performance at sequencing depths more amenable to performing diagnostic mNGS in low resource settings.


Asunto(s)
Meningitis , Mycobacterium tuberculosis , Tuberculosis Meníngea , Sistema Nervioso Central , Humanos , Meningitis/microbiología , Metagenómica , Mycobacterium tuberculosis/genética , Tuberculosis Meníngea/líquido cefalorraquídeo , Tuberculosis Meníngea/diagnóstico , Tuberculosis Meníngea/genética
9.
J Exp Biol ; 214(Pt 10): 1643-54, 2011 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-21525310

RESUMEN

We created physical models based on the morphology of ram suspension-feeding fishes to better understand the roles morphology and swimming speed play in particle retention, size selectivity and filtration efficiency during feeding events. We varied the buccal length, flow speed and architecture of the gills slits, including the number, size, orientation and pore size/permeability, in our models. Models were placed in a recirculating flow tank with slightly negatively buoyant plankton-like particles (~20-2000 µm) collected at the simulated esophagus and gill rakers to locate the highest density of particle accumulation. Particles were captured through sieve filtration, direct interception and inertial impaction. Changing the number of gill slits resulted in a change in the filtration mechanism of particles from a bimodal filter, with very small (≤ 50 µm) and very large (>1000 µm) particles collected, to a filter that captured medium-sized particles (101-1000 µm). The number of particles collected on the gill rakers increased with flow speed and skewed the size distribution towards smaller particles (51-500 µm). Small pore sizes (105 and 200 µm mesh size) had the highest filtration efficiencies, presumably because sieve filtration played a significant role. We used our model to make predictions about the filtering capacity and efficiency of neonatal whale sharks. These results suggest that the filtration mechanics of suspension feeding are closely linked to an animal's swimming speed and the structural design of the buccal cavity and gill slits.


Asunto(s)
Región Branquial/fisiología , Conducta Alimentaria/fisiología , Peces/anatomía & histología , Modelos Anatómicos , Boca/anatomía & histología , Natación/fisiología , Análisis de Varianza , Animales , Filtración , Peces/fisiología , Modelos Lineales , Tamaño de la Partícula , Especificidad de la Especie
10.
Drug Discov Today Dis Models ; 8(1): 37-46, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22081770

RESUMEN

One of the key features of cardiovascular complications, such as hypertension or diabetes, is that they often appear at the same time in the same individual together with other forms of co-morbidities. While clinically a recognized phenomenon, no molecular mechanism for such co-morbidities has received universal acceptance. We propose a new hypothesis that provides a molecular basis for co-morbidities in hypertension due to unchecked proteolytic activity and receptor destruction. Testing of the hypothesis in the spontaneously hypertensive rat reveals an unchecked matrix metalloproteinase and serine protease activity in plasma and on several cardiovascular and parenchymal cells. The elevated proteolytic activity causes extracellular cleavage of multiple receptor types, such that cleavage of one receptor type leads to loss of the function carried out by this receptor. Proteolytic cleavage of the extracellular domain of the ß(2) adrenergic receptor in arteries and arterioles causes vasoconstriction and elevation of the central blood pressure while cleavage of the extracellular domain of the insulin receptor leads to insulin resistance and lack of transmembrane glucose transport. A diverse set of cell dysfunctions in the spontaneously hypertensive rat are accompanied by cleavage of the membrane receptors that are involved in these functions. Chronic inhibition of the unchecked protease activity in the spontaneously hypertensive rat serves to restore the extracellular receptor density and alleviates the corresponding cell dysfunctions. The mild unchecked proteolytic activity in the spontaneously hypertensive rat points towards a chronic autodigestion process as a contributor to the end organ injury encountered in this rat strain. The presence of various soluble receptors, which consist of extracellular fragments of membrane receptors, in the plasma of hypertensive and diabetic patients suggest that the autodigestion process may also be present in man.

11.
Sci Rep ; 11(1): 116, 2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33420386

RESUMEN

Middle- and inner-ear surgery is a vital treatment option in hearing loss, infections, and tumors of the lateral skull base. Segmentation of otologic structures from computed tomography (CT) has many potential applications for improving surgical planning but can be an arduous and time-consuming task. We propose an end-to-end solution for the automated segmentation of temporal bone CT using convolutional neural networks (CNN). Using 150 manually segmented CT scans, a comparison of 3 CNN models (AH-Net, U-Net, ResNet) was conducted to compare Dice coefficient, Hausdorff distance, and speed of segmentation of the inner ear, ossicles, facial nerve and sigmoid sinus. Using AH-Net, the Dice coefficient was 0.91 for the inner ear; 0.85 for the ossicles; 0.75 for the facial nerve; and 0.86 for the sigmoid sinus. The average Hausdorff distance was 0.25, 0.21, 0.24 and 0.45 mm, respectively. Blinded experts assessed the accuracy of both techniques, and there was no statistical difference between the ratings for the two methods (p = 0.93). Objective and subjective assessment confirm good correlation between automated segmentation of otologic structures and manual segmentation performed by a specialist. This end-to-end automated segmentation pipeline can help to advance the systematic application of augmented reality, simulation, and automation in otologic procedures.


Asunto(s)
Automatización/métodos , Hueso Temporal/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Oído Interno/diagnóstico por imagen , Oído Interno/cirugía , Oído Medio/diagnóstico por imagen , Oído Medio/cirugía , Nervio Facial/diagnóstico por imagen , Nervio Facial/cirugía , Humanos , Periodo Preoperatorio , Hueso Temporal/cirugía
12.
Acta Biomater ; 121: 359-370, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33271358

RESUMEN

The cory catfishes (Callichthyidae) are small, South American armored catfishes with a series of dermal scutes that run the length of the fish from posterior to the parieto-supraoccipital down to the caudal peduncle. In this study, we explore the anatomy and functional performance of the armored scutes in the three-striped cory catfish, Corydoras trilineatus. The lateral surface has a dorsal and a ventral row of scutes that interact at the horizontal septum. The scutes have little overlap with sequential posterior scutes (~33% overlap) and a deep ridge in the internal surface that connects to the underlying soft tissue. The internal surface of C. trilineatus scutes is stiffer than the external surface, contrary to the findings in a related species of cory catfish, C. aeneus, which documented a hypermineralized, enamel-like, non-collagenous, hyaloine layer along the external surface of the scute. Clearing and staining of C. trilineatus scutes revealed that the scutes have highly mineralized (~50% mineralization) regions embedded in between areas of low mineralization along the posterior margin. Puncture tests showed that posterior scutes were weaker than both anterior and middle scutes, and scutes attached to the body required 50% more energy to puncture than isolated scutes. Corydoras trilineatus has the strongest armor in areas critical for protecting vital organs and the external armored scute receives synergistic benefits from interactions to the soft underlying tissue, which combine to provide a tough protective armor that still allows for flexible mobility.


Asunto(s)
Bagres , Animales
13.
Front Psychol ; 12: 645734, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34489778

RESUMEN

Parents in academic careers face notable challenges that may go unrecognized by university management and/or policy makers. The COVID-19 pandemic has shed light on some of these challenges, as academic parents shifted to working from home while simultaneously caring for children. On the other hand, many parents found that the shift to working from home offered new opportunities such as working more flexible hours, development of digital skillsets, and increased involvement in the education of their children. In this article we explore the work-related challenges and opportunities experienced by academic parents as a result of the COVID-19 pandemic and offer potential long-term solutions for academic parents and their universities. We use the following methods: (1) a literature review focused on identifying the work-related challenges academic parents faced prior to the pandemic, as well as the impact of the pandemic on scientists and working parents and (2) administer a world-wide survey with the goal of identifying the challenges and opportunities associated with parenting and academic work through the COVID-19 lockdown (304 total responses; 113 complete). Moving forward these findings have enabled conclusions to be drawn in order to shape a new normal. Our aim is to offer university administrators, policy makers, and community service providers with ways to provide additional support for academic parents as well as provide tools for academic parents to learn successful strategies directly from their peers.

14.
Sci Rep ; 9(1): 15598, 2019 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-31666594

RESUMEN

The role of interferon and interferon stimulated genes (ISG) in limiting bacterial infection is controversial, and the role of individual ISGs in the control of the bacterial life-cycle is limited. Viperin, is a broad acting anti-viral ISGs, which restricts multiple viral pathogens with diverse mechanisms. Viperin is upregulated early in some bacterial infections, and using the intracellular bacterial pathogen, S. flexneri, we have shown for the first time that viperin inhibits the intracellular bacterial life cycle. S. flexneri replication in cultured cells induced a predominantly type I interferon response, with an early increase in viperin expression. Ectopic expression of viperin limited S. flexneri cellular numbers by as much as 80% at 5hrs post invasion, with similar results also obtained for the intracellular pathogen, Listeria monocytogenes. Analysis of viperins functional domains required for anti-bacterial activity revealed the importance of both viperin's N-terminal, and its radical SAM enzymatic function. Live imaging of S. flexneri revealed impeded entry into viperin expressing cells, which corresponded to a loss of cellular cholesterol. This data further defines viperin's multi-functional role, to include the ability to limit intracellular bacteria; and highlights the role of ISGs and the type I IFN response in the control of bacterial pathogens.


Asunto(s)
Interferones/metabolismo , Proteínas/genética , Shigella flexneri/fisiología , Activación Transcripcional , Línea Celular , Colesterol/metabolismo , Regulación de la Expresión Génica , Humanos , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH
15.
Sci Adv ; 4(9): eaat9533, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30263959

RESUMEN

Solid-liquid filtration is a ubiquitous process found in industrial and biological systems. Although implementations vary widely, almost all filtration systems are based on a small set of fundamental separation mechanisms, including sieve, cross-flow, hydrosol, and cyclonic separation. Anatomical studies showed that manta rays have a highly specialized filter-feeding apparatus that does not resemble previously described filtration systems. We examined the fluid flow around the manta filter-feeding apparatus using a combination of physical modeling and computational fluid dynamics. Our results indicate that manta rays use a unique solid-fluid separation mechanism in which direct interception of particles with wing-like structures causes particles to "ricochet" away from the filter pores. This filtration mechanism separates particles smaller than the pore size, allows high flow rates, and resists clogging.


Asunto(s)
Biología Computacional/métodos , Conducta Alimentaria/fisiología , Filtración/instrumentación , Hidrodinámica , Rajidae/anatomía & histología , Rajidae/fisiología , Animales
16.
Anat Rec (Hoboken) ; 300(9): 1695-1704, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28390152

RESUMEN

Reproduction is a critical aspect of understanding the biology of fishes. Relatively little is known about oarfish (Regalecus russellii) reproduction; however, strandings of dead animals have provided a rare opportunity to investigate the gonadal morphology of four fish: two females and two males. A female collected in June 2015 (4.32 m TL) had bifurcated ovaries 2.14 m in length and 2.14 kg. The gonadosomatic index (GSI) was 11.8% and the fish was determined to be spawning capable/spawning reproductive phase. A female that stranded in Sept. 2015 (5.20 m TL) had bifurcated ovaries 1.43 m in length and 1.28 kg with a GSI of 1.55%. The Sept. female was in a regressing phase of reproduction. A male collected in Aug. 2015 (4.30 m TL) had 64.7-cm-long testes that weighed 40.1 g. The GSI was 0.05% representing a regressing phase of reproduction. A male collected in Nov. 2015 (4.10 m TL) had testes 104.0 cm in length and 467.0 g with a GSI of 0.59%. The Nov. male was in a spawning/spawning capable phase of reproduction. We described ovarian follicles and sperm cells based on size classes and cytological characteristics. We concluded that oarfish are likely batch spawners that undergo periods of regression after a spawning event or season. While this study is not complete with respect to the annual reproductive cycle of oarfish, it markedly contributes to our overall understanding of this rare, mesopelagic fish. Anat Rec, 300:1695-1704, 2017. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Peces/anatomía & histología , Ovario/anatomía & histología , Espermatogénesis , Testículo/anatomía & histología , Animales , Femenino , Masculino
17.
PeerJ ; 4: e2586, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27833795

RESUMEN

We present genetic and morphometric support for a third, distinct, and recently diverged group of Manta ray that appears resident to the Yucatán coastal waters of the Gulf of Mexico. Individuals of the genus Manta from Isla Holbox are markedly different from the other described manta rays in their morphology, habitat preference, and genetic makeup. Herein referred to as the Yucatán Manta Ray, these individuals form two genetically distinct groups: (1) a group of mtDNA haplotypes divergent (0.78%) from the currently recognized Manta birostris and M. alfredi species, and (2) a group possessing mtDNA haplotypes of M. birostris and highly similar haplotypes. The latter suggests the potential for either introgressive hybridization between Yucatán Manta Rays and M. birostris, or the retention of ancestral M. birostris signatures among Yucatán Manta Rays. Divergence of the genetically distinct Yucatán Manta Ray from M. birostris appears quite recent (<100,000 YBP) following fit to an Isolation-with-Migration model, with additional support for asymmetrical gene flow from M. birostris into the Yucatán Manta Ray. Formal naming of the Yucatán Manta Ray cannot yet be assigned until an in-depth taxonomic study and further confirmation of the genetic identity of existing type specimens has been performed.

18.
Ann Cardiol Angeiol (Paris) ; 54(5): 250-6, 2005 Sep.
Artículo en Francés | MEDLINE | ID: mdl-16237914

RESUMEN

AIM: To compare the assessment of infarct size using MRI and peak CK value. POPULATION AND METHODS: 16 patients presenting with a first MI and seriall measurement of CK underwent gadolinium-enhanced MRI. RESULTS: A significant correlation was observed between both estimates of infarct size (r=0.56, p=0.0025). In addition, an inverse correlation was found between residual viability and peak CK (r=-0.51; p=0.043). CONCLUSION: After a first episode of MI, infarct size estimate by MRI correlates with that determined by peak CK measurement.


Asunto(s)
Creatina Quinasa/sangre , Imagen por Resonancia Magnética , Infarto del Miocardio/sangre , Infarto del Miocardio/patología , Anciano , Anciano de 80 o más Años , Medios de Contraste/administración & dosificación , Femenino , Gadolinio DTPA , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
19.
Integr Comp Biol ; 55(1): 97-109, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25980566

RESUMEN

When feeding, most aquatic organisms generate suction that draws prey into the mouth. The papers in this volume are a demonstration of this fact. However, under what circumstances is suction ineffective as a feeding mechanism? Here we consider the interplay between suction, ram, and biting, and analyze the contribution of each to the capture of prey by a wide variety of species of fish. We find, not surprisingly, that ram is the dominant contributor to feeding because suction, and biting, are only effective when very close to the prey. As species utilize more strongly ram-dominated modes of feeding, they may be released from the morphological and behavioral constraints associated with the need to direct a current of water into the head. Morphological and behavioral changes that facilitate larger gapes and stronger jaws are explored here, including predators that lack a protrusile upper jaw, predators with elongate jaws, predators that rely on suspension feeding, and predators that bite. Interestingly, while the mobility of the jaws and the shape of the opening of the mouth are modified in species that have departed from a primary reliance on suction feeding, the anterior-to-posterior wave of expansion persists. This wave may be greatly slowed in ram and biting species, but its retention suggests a fundamental importance to aquatic feeding.


Asunto(s)
Conducta Alimentaria , Peces/anatomía & histología , Peces/fisiología , Conducta Predatoria , Animales , Evolución Biológica , Fenómenos Biomecánicos , Maxilares/anatomía & histología , Maxilares/fisiología , Succión
20.
Endocrinology ; 142(7): 2985-95, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11416020

RESUMEN

A complementary DNA, uterine-ovarian-specific gene 44 (UO-44), has been isolated from tamoxifen-induced rat uterine complementary DNA library using differential display techniques. UO-44 transcripts are found to be abundant in the uterus and ovary. UO-44 gene expression in the uterus is strictly regulated by estrogens, tamoxifen, and GH, whereas the pure antiestrogen ICI 182780 is inhibitory. Treatment of ovariectomized rats and hypophysectomized rats with tamoxifen and GH, respectively, resulted in up-regulation of UO-44 expression in a dose-dependent manner. In situ hybridization revealed that UO-44 gene expression was restricted to the luminal and glandular epithelial cells of the uterus and to granulosa cells of medium-size ovarian follicles. Transfection studies showed that UO-44 was a membrane-associated protein. Because estrogens, tamoxifen, and GH are stimulators of uterine luminal epithelial cell growth in vivo, UO-44 protein may serve as a mediator of the effect of these compounds in inducing epithelial proliferation and differentiation in these tissues.


Asunto(s)
ADN Complementario/genética , Estradiol/análogos & derivados , Antagonistas de Estrógenos/farmacología , Regulación de la Expresión Génica , Ovario/efectos de los fármacos , Tamoxifeno/farmacología , Útero/efectos de los fármacos , Animales , ADN Complementario/aislamiento & purificación , ADN Complementario/metabolismo , Estradiol/farmacología , Femenino , Fulvestrant , Humanos , Ovariectomía , Ovario/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Fracciones Subcelulares/metabolismo , Distribución Tisular , Células Tumorales Cultivadas , Útero/metabolismo
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