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1.
Biochimie ; 190: 24-35, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34242726

RESUMO

Over the past decades, much have been learned about HIV-1 virus and its molecular strategies for pathogenesis. However, HIV-1 still remains an enigmatic virus, particularly because of its unique proteins. Establishment of latency and reactivation is still a puzzling question and various temporal and spatial dynamics between HIV-1 proteins itself have given us new way of thinking about its pathogenesis. HIV-1 replication depends on Tat which is a small unstructured protein and subjected to various post-translational modifications for its myriad of functions. HIV-1 Tat protein modulates the functions of various strategic cellular pathways like proteasomal machinery and inflammatory pathways to aid in HIV-1 pathogenesis. Many of the recent findings have shown that Tat is associated with exosomes, cleared from HIV-1 infected cells through its degradation by diverse routes ranging from lysosomal to proteasomal pathways. HIV-1 Tat was also found to be associated with other HIV-1 proteins including Vpr, Nef, Nucleocapsid (NC) and Rev. Interaction of Tat with Vpr and Nef increases its transactivation function, whereas, interaction of Tat with NC or Rev leads to Tat protein degradation and hence suppression of Tat functions. Research in the recent years has established that Tat is not only important for HIV-1 promoter transactivation and virus replication but also modulating multiple cellular and molecular functions leading to HIV-1 pathogenicity. In this review we discussed various transcriptional and non-transcriptional HIV-1 Tat functions which modulate host cell metabolism during HIV-1 pathogenesis.


Assuntos
HIV-1/fisiologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana/fisiologia , Animais , Apresentação de Antígeno/fisiologia , Apoptose/fisiologia , Autofagia/fisiologia , Secreções Corporais/fisiologia , Regulação da Expressão Gênica , HIV-1/imunologia , Humanos , Estresse Oxidativo/fisiologia , Proteólise , Produtos do Gene tat do Vírus da Imunodeficiência Humana/imunologia
2.
Zoology (Jena) ; 147: 125941, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34126327

RESUMO

Flamingos inhabit specialized habitats and breed in large colonies, building their nests on islands that limit the access of terrestrial predators. Many aspects of their uropygial gland are still unknown. The uropygial gland, a sebaceous organ exclusive to birds, shares some histological features among species such as the presence of a capsule, adenomers with stratified epithelium and secondary and primary chambers. We found that the uropygial gland of the Chilean Flamingo (Phoenicopterus chilensis) displays most of these characteristics but lacks a primary storage chamber. This absence may be an adaptation to their aquatic environment. The uropygial secretion of this species has a variety of glycoconjugates while its lipid moiety is largely dominated by waxes and minor amounts of triacylglycerols and fatty acids. Mass spectrometry analysis of the preen wax showed branched fatty acids of varied chain length and unbranched fatty alcohols, resulting in a complex mixture of wax esters and no differences between sexes were observed. The glycoconjugates present in the preen secretion could play a role as antimicrobial molecules, as suggested for other bird species, while the absence of diester waxes in flamingos might be related with their nesting habits and limited exposure to predation. Our results were evaluated according to physiological and ecological aspects of the flamingo's biology.


Assuntos
Estruturas Animais/fisiologia , Aves/fisiologia , Secreções Corporais/química , Estruturas Animais/anatomia & histologia , Animais , Secreções Corporais/fisiologia , Feminino , Masculino , Tamanho do Órgão , Especificidade da Espécie
3.
J Sex Marital Ther ; 47(1): 32-42, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32772643

RESUMO

Changes in vaginal blood flow and lubrication are primary components of physiological sexual arousal in women. Despite the existence of well-established tools for measuring vaginal blood flow, there is not yet a consistently implemented measure of physiological lubrication. To address this methodological gap, researchers have begun examining the utility of litmus test strips, primarily in sexually healthy women. The present study builds on this work by examining the utility of an alternative tool, the Schirmer Tear Test strips, in women with (n = 32) and without (n = 32) sexual arousal concerns. Significant increases in physiological lubrication were found in response to a sexual film, and these changes were moderately correlated with self-reported genital arousal (r = .41) and lubrication (r = .30). No between-group differences in lubrication were observed. These results indicate the Schirmer Tear Test strips are sensitive enough to detect increases in lubrication and may be valuable in clinical and research assessments of female sexual arousal.


Assuntos
Secreções Corporais/fisiologia , Muco do Colo Uterino/fisiologia , Excitação Sexual , Vagina/fisiologia , Adulto , Estudos de Viabilidade , Feminino , Humanos , Lubrificação , Pessoa de Meia-Idade , Fitas Reagentes/administração & dosagem , Autorrelato , Adulto Jovem
4.
Placenta ; 102: 21-26, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33218574

RESUMO

Development of the placenta must always be in advance of that of the embryo. Evidence from domestic species demonstrates that the placenta is capable of stimulating its own development through a signalling dialogue with the endometrial glands. Placental lactogens produced by the trophoblast lead to increased expression and release of uterine secretions and mitogenic growth factors, including epidermal growth factor, that have a close temporal and spatial relationship with trophoblast proliferation. Here, we review evidence that an equivalent mechanism operates in the human. The same repertoire of receptors is present on the endometrial gland cells, and the epithelial cells have long been known to adopt a hypersecretory phenotype following an implantation. Furthermore, early pregnancy hormones stimulate the secretion of glycodelin-A and osteopontin, two 'uterine milk proteins' that have multiple potential effects at the maternal-placental interface, from organoid cultures derived from endometrial glands. Prolactin appears to be an important stimulant, but unlike in domestic species the human trophoblast does not secrete this hormone. Instead, it is a major product of decidual cells. Hence, complications of pregnancy that have their pathophysiological roots in deficient trophoblast proliferation may be due primarily to problems of decidualisation. Ensuring the endometrium is in an optimal state pre-conceptionally should therefore be a priority for women's health. Trophoblast stemness and proliferative capacity show a sharp decline at the switch from histotrophic to haemotrophic nutrition. This may reflect the increase in oxygen concentration or loss of growth factor support. Either way, there are implications for adaptive growth of the organ.


Assuntos
Endométrio/fisiologia , Placentação , Animais , Secreções Corporais/fisiologia , Desenvolvimento Embrionário , Feminino , Humanos , Troca Materno-Fetal , Gravidez
5.
Philos Trans R Soc Lond B Biol Sci ; 375(1813): 20200077, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33070736

RESUMO

The role of non-gametic components of the ejaculate (seminal fluid) in fertility and sperm competitiveness is now well established. Surprisingly, however, we know far less about female reproductive fluid (FRF) in the context of sexual selection, and insights into male-FRF interactions in the context of sperm competition have only recently emerged. Despite this limited knowledge, evidence from taxonomically diverse species has revealed insights into the effects of FRF on sperm traits that have previously been implicated in studies of sperm competition. Specifically, through the differential effects of FRF on a range of sperm traits, including chemoattraction and alterations in sperm velocity, FRF has been shown to exert positive phenotypic effects on the sperm of males that are preferred as mating partners, or those from the most compatible or genetically diverse males. Despite these tantalizing insights into the putative sexually selected functions of FRF, we largely lack a mechanistic understanding of these processes. Taken together, the evidence presented here highlights the likely ubiquity of FRF-regulated biases in fertilization success across a diverse range of taxa, thus potentially elevating the importance of FRF to other non-gametic components that have so far been studied largely in males. This article is part of the theme issue 'Fifty years of sperm competition'.


Assuntos
Secreções Corporais/fisiologia , Fertilização , Genitália Feminina/fisiologia , Comportamento Sexual Animal , Animais , Feminino , Masculino , Espermatozoides/fisiologia
6.
Plant Cell Environ ; 43(12): 2912-2931, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32542760

RESUMO

The Plumbaginaceae (non-core Caryophyllales) is a family well known for species adapted to a wide range of arid and saline habitats. Of its salt-tolerant species, at least 45 are in the genus Limonium; two in each of Aegialitis, Limoniastrum and Myriolimon, and one each in Psylliostachys, Armeria, Ceratostigma, Goniolimon and Plumbago. All the halophytic members of the family have salt glands and salt glands are also common in the closely related Tamaricaceae and Frankeniaceae. The halophytic species of the three families can secrete a range of ions (Na+ , K+ , Ca2+ , Mg2+ , Cl- , HCO3- , SO42- ) and other elements (As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn). Salt glands are, however, absent in salt-tolerant members of the sister family Polygonaceae. We describe the structure of the salt glands in the three families and consider whether glands might have arisen as a means to avoid the toxicity of Na+ and/or Cl- or to regulate Ca2+ concentrations with the leaves. We conclude that the establishment of lineages with salt glands took place after the split between the Polygonaceae and its sister group the Plumbaginaceae.


Assuntos
Plumbaginaceae/fisiologia , Adaptação Fisiológica , Evolução Biológica , Secreções Corporais/fisiologia , Plumbaginaceae/anatomia & histologia , Plantas Tolerantes a Sal/anatomia & histologia , Plantas Tolerantes a Sal/fisiologia , Estresse Fisiológico
7.
Microsc Microanal ; 26(3): 609-621, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32495729

RESUMO

Mauritia flexuosa palms inhabit wetland environments in the dry, seasonal Brazilian savanna (Cerrado) and produce mucilaginous secretions in the stem and petiole that have a medicinal value. The present study sought to characterize the chemical natures of those secretions and to describe the anatomical structures involved in their synthesis. Chemical analyzes of the secretions, anatomical, histochemical analyses, and electron microscopy studies were performed on the roots, stipes, petioles, and leaf blades. Stipe and petiole secretions are similar, and rich in cell wall polysaccharides and pectic compounds such as rhamnose, arabinose, xylose, mannose, galactose, and glucose, which are hydrophilic largely due to their hydroxyl and carboxylate groups. Mucilaginous secretions accumulate in the lumens of vessel elements and sclerenchyma fibers of the root, stipe, petiole, and foliar veins; their synthesis involves cell wall loosening and the activities of dictyosomes. The outer faces of the cell walls of the parenchyma tissue in the mesophyll expand to form pockets that rupture and release pectocellulose substances into the intercellular spaces. The presence of mucilage in the xylem, extending from the roots to the leaf veins and continuous with the leaf apoplast, and sub-stomatal chambers suggest a strategy for plant water economy.


Assuntos
Arecaceae/metabolismo , Secreções Corporais/fisiologia , Folhas de Planta/citologia , Polissacarídeos/metabolismo , Áreas Alagadas , Xilema/citologia , Arabinose , Brasil , Parede Celular , Galactose , Glucose , Manose , Folhas de Planta/metabolismo , Raízes de Plantas/citologia , Ramnose , Xilema/metabolismo , Xilose
8.
Nutrients ; 12(5)2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403450

RESUMO

Some temporary double enterostomies (DES) or entero-atmospheric fistulas (EAF) have high output and are responsible for Type 2 intestinal failure. Intravenous supplementations (IVS) for parenteral nutrition and hydration compensate for intestinal losses. Chyme reinfusion (CR) artificially restores continuity pending surgical closure. CR treats intestinal failure and is recommended by European Society for Clinical Nutrition and Metabolism (ESPEN) and American Society for Parenteral and Enteral Nutrition (ASPEN) when possible. The objective of this study was to show changes in nutritional status, intestinal function, liver tests, IVS needs during CR, and the feasibility of continuing it at home. A retrospective study of 306 admitted patients treated with CR from 2000 to 2018 was conducted. CR was permanent such that a peristaltic pump sucked the upstream chyme and reinfused it immediately in a tube inserted into the downstream intestine. Weight, plasma albumin, daily volumes of intestinal and fecal losses, intestinal nitrogen, and lipid absorption coefficients, plasma citrulline, liver tests, and calculated indices were compared before and during CR in patients who had both measurements. The patients included 185 males and 121 females and were 63 ± 15 years old. There were 37 (12%), 269 (88%) patients with EAF and DES, respectively. The proximal small bowel length from the duodeno-jejunal angle was 108 ± 67 cm (n = 232), and the length of distal small intestine was 117 ± 72 cm (n = 253). The median CR start was 5 d (quartile 25-75%, 2-10) after admission and continued for 64 d (45-95), including 81 patients at home for 47 d (28-74). Oral feeding was exclusive 171(56%), with enteral supplement 122 (42%), or with IVS 23 (7%). Before CR, 211 (69%) patients had IVS for nutrition (77%) or for hydration (23%). IVS were stopped in 188 (89%) 2 d (0-7) after the beginning of CR and continued in 23 (11%) with lower volumes. Nutritional status improved with respect to weight gain (+3.5 ± 8.4%) and albumin (+5.4 ± 5.8 g/L). Intestinal failure was cured in the majority of cases as evidenced by the decrease in intestinal losses by 2096 ± 959 mL/d, the increase in absorption of nitrogen 32 ± 20%, of lipids 43 ± 30%, and the improvement of citrulline 13.1 ± 8.1 µmol/L. The citrulline increase was correlated with the length of the distal intestine. The number of patients with at least one liver test >2N decreased from 84-40%. In cases of Type 2 intestinal failure related to DES or FAE with an accessible and functional distal small bowel segment, CR restored intestinal functions, reduced the need of IVS by 89% and helped improve nutritional status and liver tests. There were no vital complications or infectious diarrhea described to date. CR can become the first-line treatment for intestinal failure related to double enterostomy and high output fistulas.


Assuntos
Secreções Corporais/fisiologia , Enterostomia/efeitos adversos , Enterostomia/métodos , Soluções de Nutrição Parenteral , Nutrição Parenteral/métodos , Síndrome do Intestino Curto/terapia , Idoso , Ácidos e Sais Biliares/fisiologia , Digestão/fisiologia , Duodeno/fisiopatologia , Feminino , Suco Gástrico , Humanos , Absorção Intestinal/fisiologia , Jejuno/fisiopatologia , Masculino , Pessoa de Meia-Idade , Suco Pancreático , Saliva , Síndrome do Intestino Curto/etiologia , Síndrome do Intestino Curto/fisiopatologia , Resultado do Tratamento
9.
Am J Perinatol ; 37(13): 1335-1339, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31365933

RESUMO

OBJECTIVE: This study aimed to increase the understanding of secretion management in infants with tracheostomies. In this case series, we describe objective evidence for an unconventional approach in infants refractory to conventional management techniques. STUDY DESIGN: Case study of two NICU infants utilizing high-resolution manometry was undertaken using personalized oral stimulation protocols with fruity foods. RESULTS: Oral stimulation improved infant swallowing to clear secretions and reduce the need for suctioning. CONCLUSION: Innovative oral stimulation protocols are needed to improve swallowing in high-risk infants.


Assuntos
Secreções Corporais/fisiologia , Manometria/métodos , Sucção/estatística & dados numéricos , Traqueostomia , Deglutição/fisiologia , Terapia por Estimulação Elétrica/métodos , Feminino , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino
10.
Clin Respir J ; 13(11): 728-732, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31436883

RESUMO

INTRODUCTION: Atelectasis is a common problem in intensive care units. It usually occurs due to airway obstruction caused by pulmonary secretions. As the left main bronchus angulates from carina more sharply, suctioning of the secretions from left side is less effective, causing failure in treatment of left lung atelectases. If chest physiotherapy and medical treatment fail, bronchoscopy should be considered; but it requires experience, time, effort and a higher cost. OBJECTIVES: To evaluate the success of a novel method "selective left bronchial aspiration (SeLBA)" in the treatment of left lung atelectases. METHODS: The study consisted of 10 patients who suffered left lung atelectasis and treated with double catheter suctioning technique, SeLBA in Pediatric Intensive Care Unit of Hacettepe University Ihsan Dogramaci Children's Hospital between June 2017 and February 2019. The outcomes were evaluated by comparing the chest X-rays before and after the procedure. RESULTS: All of the patients' atelectases resolved successfully by SeLBA procedure. CONCLUSION: We introduce this novel technique of reopening the atelectased left lung as a rapid, safe and practical alternative for bronchoscopic clear away.


Assuntos
Pulmão/patologia , Atelectasia Pulmonar/cirurgia , Sucção/métodos , Adolescente , Obstrução das Vias Respiratórias/complicações , Obstrução das Vias Respiratórias/fisiopatologia , Obstrução das Vias Respiratórias/cirurgia , Secreções Corporais/fisiologia , Broncoscopia/economia , Broncoscopia/métodos , Catéteres/normas , Criança , Feminino , Humanos , Lactente , Unidades de Terapia Intensiva , Masculino , Modalidades de Fisioterapia/tendências , Atelectasia Pulmonar/diagnóstico , Atelectasia Pulmonar/etiologia , Atelectasia Pulmonar/fisiopatologia , Radiografia Torácica/métodos , Traqueia/cirurgia , Resultado do Tratamento
11.
J Insect Physiol ; 117: 103914, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31323235

RESUMO

Moulting, especially in 'hemimetabolous' insects that emerge upside down, is a crucial moment in their live. Losing their attachment during this situation can be fatal for survival. We here studied the emergence of dragonfly adults, describe structures involved in larval attachment to the substrate, and biomechanically test the pull-off forces of exuviae to natural substrates. Confocal laser scanning microscopy and scanning electron microscopy were used to describe both morphology and material composition of the leg cuticle of Anax imperator larvae. The results show that the combination of morphological and behavioral adaptations provides reliable anchorage of exuviae to the substrates. We determined a safety factor of 14, and demonstrated that this staggered safety system experiencing several unlocking and relocking events withstand multiple disturbances before the entire exuvia is completely detaches. This furthers our understanding of interlocking and anchorage of insects in general and may allow for future applications.


Assuntos
Secreções Corporais/fisiologia , Muda , Odonatos/fisiologia , Animais , Larva/fisiologia
12.
Respir Care ; 64(11): 1377-1386, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31064802

RESUMO

BACKGROUND: Clinicians may use adventitious breath sounds on lung auscultation and a "sawtooth" pattern on the ventilator expiratory flow waveform as indicators of the need for chest physiotherapy for airway-secretion clearance in mechanically ventilated patients. This study seeks to identify potential clinical and novel indicators of the weight of airway secretions cleared from a single session of chest physiotherapy in mechanically ventilated subjects. METHODS: We recorded airway crackles using artificial airway acoustic sound monitoring and computerized lung-sound amplitude using artificial airway acoustic sound detection and compared them to standard clinical assessments in 71 mechanically ventilated subjects immediately prior to a single session of chest physiotherapy. Correlational analyses were undertaken between the weight of airway secretions obtained after the single session of chest physiotherapy as the dependent variable and novel assessments, clinical assessments, patient characteristics, and ventilator parameters as the independent variables. Multiple linear regression analyses were then used to determine the best model to predict the weight of airway secretions obtained from the single chest physiotherapy session. Data are reported as mean and median as appropriate. Significance was set at P < .05. RESULTS: 71 mechanically ventilated subjects were included for analysis. Statistically significant associations with the weight of airway secretions included the presence of a sawtooth waveform on expiration and the novel assessment of average airway crackles during inspiration. The best predictive model of the weight of airway secretions included the presence of the sawtooth waveform on expiration and ventilator tidal volume. CONCLUSIONS: Simple clinical assessments used in this study were able to independently predict the weight of airway secretions cleared during a single session of chest physiotherapy. The novel assessments used in this investigation did not add any further value.


Assuntos
Manuseio das Vias Aéreas/métodos , Auscultação/métodos , Oscilação da Parede Torácica/métodos , Respiração Artificial , Terapia Respiratória/métodos , Secreções Corporais/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modalidades de Fisioterapia , Respiração Artificial/instrumentação , Respiração Artificial/métodos , Ventiladores Mecânicos
13.
Am J Phys Anthropol ; 166(4): 884-894, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29719049

RESUMO

OBJECTIVES: Sexual selection has seemingly influenced chemical communication in numerous non-human primates, although it is unclear whether it has influenced strictly pair-living and pair-bonded taxa. The physical similarities between male and female owl monkeys suggest that disruptive selection has not played a role in this taxon. However, given their nocturnality, olfactory traits may show differing patterns of sexual selection than visual traits. If sexual selection has influenced chemical communication in owl monkeys, we expect larger scent glands and greater scent-marking in females given the high degree of paternal care, as has been proposed for callitrichines. MATERIALS AND METHODS: We evaluated sex differences in the qualitative and quantitative descriptions of the subcaudal and perianal glandular regions of captive male (n = 39) and female (n = 36) owl monkeys (A. nancymaae), and in the olfactory behaviors performed within breeding pairs (n = 16). RESULTS: Males had larger areas of secretion retained in the hairs covering the subcaudal gland, and females had more and darker secretion than males covering the perianal region. Males inspected the genital region of their partners more frequently than females did, but the sexes did not differ much in other investigative and marking behaviors. DISCUSSION: The observed sex differences and variation in olfactory traits are consistent with the hypothesis that sexual selection has influenced chemical communication in owl monkeys, with males having larger subcaudal glands and spending more time investigating odors. Still, sex differences in monogamous owl monkeys were less extreme than those in other, non-monogamous, taxa.


Assuntos
Aotidae/fisiologia , Ligação do Par , Glândulas Odoríferas/fisiologia , Olfato/fisiologia , Animais , Antropologia Física , Comportamento Animal/fisiologia , Secreções Corporais/fisiologia , Feminino , Masculino , Caracteres Sexuais
14.
Sci Rep ; 8(1): 7701, 2018 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-29799016

RESUMO

Social cohesion in social insect colonies can be achieved through the use of chemical signals whose production is caste-specific and regulated by social contexts. In honey bees, queen mandibular gland pheromones (QMP) maintain reproductive dominance by inhibiting ovary activation and production of queen-like mandibular gland signals in workers. We investigated whether honey bee queens can control reproductively active workers of the intraspecific social parasite Apis mellifera capensis, parasitising A. m. scutellata host colonies. Our results show that the queen's QMP suppresses ovarian activation and inhibits the production of QMP pheromone signals by the parasitic workers, achieved through differential expression of enzymes involved in the biosynthesis of these pheromones at two points in the biosynthetic pathway. This is the first report showing that honey bee queens can regulate reproduction in intraspecific social parasites and deepens our understanding of the molecular mechanisms involved in the regulation of worker reproduction in social insects.


Assuntos
Abelhas/fisiologia , Comportamento Competitivo/fisiologia , Dominação-Subordinação , Mandíbula/metabolismo , Glândulas Odoríferas/metabolismo , Comportamento Sexual Animal/fisiologia , Animais , Secreções Corporais/fisiologia , Feminino , Masculino , Feromônios/metabolismo , Reprodução/fisiologia , Comportamento Social , Predomínio Social , Simbiose/fisiologia
15.
Sci Rep ; 8(1): 3576, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29476100

RESUMO

Amphibian skin is rich in mucous glands and poison glands, secreting substances important for gas exchange and playing a fundamental role in chemical defense against predators and microorganisms. In the caecilian Siphonops annulatus (Mikan, 1920) we observed a concentration of enlarged mucous glands in the head region. In the posterior region of the body a similar concentration is made up of enlarged poison glands. These accumulations of glands structurally resemble the macroglands previously reported in anurans and salamanders. The skin glands in these regions are each surrounded by collagen walls forming a honeycomb-like structure. The collagen network in the head region firmly attaches to tiny pits in the bones of the skull. The two extremities of the body produce different secretions, containing exclusive molecules. Considering the fossorial lifestyle of caecilians, it seems evident that the secretions of the head and caudal region serve different functions. The anterior macrogland of mucous glands, rich in mucous/lipid secretion, in conjunction with the funnel-shaped head, may act to lubricate the body and penetrate the soil, thus facilitating locomotion underground. The blunt posterior end bearing an internalized macrogland of poison glands in the dermis may act in chemical defense and/or by blocking invasion of tunnels.


Assuntos
Anuros/fisiologia , Evolução Biológica , Glândulas Exócrinas/fisiologia , Fenômenos Fisiológicos da Pele , Animais , Anuros/metabolismo , Secreções Corporais/fisiologia , Derme/fisiologia , Glândulas Exócrinas/metabolismo , Venenos/metabolismo , Pele/química , Pele/metabolismo , Crânio/fisiologia
16.
IEEE/ACM Trans Comput Biol Bioinform ; 15(5): 1660-1668, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28796621

RESUMO

Secretions in the airways of mechanical ventilated patients are extremely dangerous to patients' health. In recent studies, the continuous constant airflow is adopted, however, it is not consistent with a clinical situation. To study respiratory airflow dynamic characteristics with secretion in the airways, a mathematical model based on clinical mechanical ventilation is established in this paper. To illustrate the secretion's influence on the airflow dynamics of mechanical ventilated respiratory system, three key parameters which are cross section area ratio of secretion/ pipe, air-secretion contact area, and secretion viscosity are involved in the study. Through the experimental study, the accuracy and dependability of the model are confirmed. By the simulation study, we find that: based on the model which combines two airways and two model lungs, when one of the airways was covered with secretion, the maximum pressure of the model lung which is attached to the end of this airway maintains constant when the cross section area ratio is less than 66 percent, and then it tends to decline sharply with the ratio increasing, but it remains constant with the augment of air-secretion contact area, the maximum flow declines both with the increasing of cross section area ratio and air-secretion contact area. Furthermore, as for the other airway, the maximum pressure of the model lung has no significant changes with the augment of area ratio and air-secretion contact area, however, along with the increasing of area ratio and air-secretion contact area, the maximum flow rises up. Moreover, the secretion viscosity has barely any influence on airflow dynamics. According to our analysis results, we conclude that the cross section area ratio of secretion/pipe has bigger influence on airflow dynamic characteristics than air-secretion contact area and secretion viscosity. This paper lays the foundation for the further study of efficacy and safety in mechanical ventilation and the secretion clearance of mechanical ventilated patients. In addition, the mathematical model proposed in this paper can also be referred to study on the secretion movement in human airways.


Assuntos
Secreções Corporais/fisiologia , Pulmão/fisiologia , Ventilação Pulmonar/fisiologia , Respiração Artificial , Mecânica Respiratória/fisiologia , Biologia Computacional , Humanos , Modelos Biológicos
17.
Int Urogynecol J ; 29(5): 621-629, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29285596

RESUMO

INTRODUCTION AND HYPOTHESIS: Women expel various kinds of fluids during sexual activities. These are manifestations of sexual arousal and orgasm or coital incontinence. This study is aimed at suggesting a diagnostic scheme to differentiate among these phenomena. METHODS: Web of Science and Ovid (MEDLINE) databases were systematically searched from 1950 to 2017 for articles on various fluid expulsion phenomena in women during sexual activities, which contain relevant information on sources and composition of the expelled fluids. RESULTS: An ultra-filtrate of blood plasma of variable quantity, which is composed of transvaginal transudate at sexual stimulation, enables vaginal lubrication. Female ejaculation (FE) is the secretion of a few milliliters of thick, milky fluid by the female prostate (Skene's glands) during orgasm, which contains prostate-specific antigen. Squirting (SQ) is defined as the orgasmic transurethral expulsion of tenths of milliliters of a form of urine containing various concentrations of urea, creatinine, and uric acid. FE and SQ are two phenomena with different mechanisms. Coital incontinence (CI) could be classified into penetration and orgasm forms, which could be associated with stress urinary incontinence or detrusor hyperactivity. CONCLUSION: Squirting, FE, and CI are different phenomena with various mechanisms and could be differentiated according to source, quantity, expulsion mechanism, and subjective feelings during sexual activities.


Assuntos
Secreções Corporais/fisiologia , Coito , Ejaculação , Orgasmo , Ejaculação/fisiologia , Feminino , Humanos , Comportamento Sexual , Uretra , Incontinência Urinária por Estresse/fisiopatologia
18.
Reprod Fertil Dev ; 29(6): 1096-1106, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27112984

RESUMO

Spermatozoa undergo several modifications in the oviduct before acquiring fertilising capacity. Although spermatozoa are exposed to similar conditions in the oviduct, the speed of the response varies with the male and the state of the spermatozoa. We hypothesised that spermatozoa from bulls with different fertility may differ in their ability to respond to oviductal fluid (ODF). Frozen-thawed spermatozoa from four bulls were incubated with oestrus oviductal fluid (OODF) for 6h. Sperm kinematics, tyrosine phosphorylation, phosphorylation patterns, capacitation and acrosome reaction were analysed at hourly intervals. The amplitude of lateral head displacement (ALH) and straightness coefficient (STR) were higher (P<0.05) in bulls with higher fertility compared with those with lower fertility, at 1-4h of incubation. At 4h of incubation and onwards, spermatozoa from bulls with higher fertility showed a lower degree (P<0.05) of tyrosine phosphorylation and higher degree of capacitation and acrosome reaction. At least five tyrosine-phosphorylated sperm proteins were detected in all bulls. However, the expression of two phosphorylated sperm proteins (183 and 109 kDa) was upregulated in bulls with lower fertility. It may be concluded that cryopreserved spermatozoa from high- and low- fertile bulls differ in their ability to respond to OODF. This may help in developing tools for assessing fertility of bulls, once validated in more animals.


Assuntos
Secreções Corporais/fisiologia , Infertilidade Masculina/veterinária , Oviductos/metabolismo , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Reação Acrossômica , Animais , Animais Endogâmicos , Secreções Corporais/metabolismo , Bovinos , Criopreservação/veterinária , Indústria de Laticínios , Estro , Feminino , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/patologia , Infertilidade Masculina/fisiopatologia , Cinética , Masculino , Oviductos/fisiologia , Fosforilação , Processamento de Proteína Pós-Traducional , Preservação do Sêmen/veterinária , Índice de Gravidade de Doença , Capacitação Espermática , Espermatozoides/patologia , Suécia , Tirosina/metabolismo
19.
J Diabetes Complications ; 31(1): 241-244, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27623390

RESUMO

BACKGROUND: miR-126 may increase angiogenesis in patients with diabetic foot ulcers (DFUs) treated with maggot debridement therapy (MDT). METHODS: Real-time quantitative PCR was used to detect expression of miR-126 mRNA in the peripheral blood among the non-diabetic population, type 2 diabetes mellitus patients without DFU, and patients with DFUs of type 2 diabetes mellitus. The expression of miR-126 mRNA in the peripheral blood of patients with DFUs was observed before and after MDT. Finally, human umbilical vein endothelial cells (HUVEC) were utilized to explore miR-126 mRNA expression with maggot excretions/secretions (ES). RESULTS: In the patients with DFUs, the miR-126 mRNA expression level in the peripheral blood was less than that type 2 diabetes mellitus patients without DFU, and much lower than that in the non-diabetic population (P<0.001). The miR-126 expression level was significantly increased in those DFU patients treated with MDT (P<0.05). Finally, using HUVEC co-cultured with ES, we showed the ES increased miR-126 expression in vitro (P<0.001). CONCLUSION: MDT upregulates the miR-126 expression in the peripheral blood of patients with DFUs.


Assuntos
Terapia Biológica/métodos , Terapias Complementares , Desbridamento/métodos , Diabetes Mellitus Tipo 2/complicações , Pé Diabético/terapia , Dípteros/fisiologia , MicroRNAs/agonistas , Idoso , Animais , Secreções Corporais/fisiologia , Células Cultivadas , China , Técnicas de Cocultura , Pé Diabético/sangue , Pé Diabético/metabolismo , Pé Diabético/patologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Feminino , Regulação da Expressão Gênica , Vida Livre de Germes , Hospitais Urbanos , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Larva/fisiologia , Masculino , MicroRNAs/sangue , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Regulação para Cima
20.
Zoology (Jena) ; 120: 73-82, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27646066

RESUMO

Bio-adhesion is a common and crucial process in nature and is used by several different species for camouflage, prey capture, hatching or to avoid drifting. Four genera of cephalopods belonging to four different families (Euprymna, Sepiolidae; Idiosepius, Idiosepiidae; Nautilus, Nautilidae; and Sepia, Sepiidae) produce glue for temporary attachment. Euprymna species live in near-shore benthic habitats of the Indo-Pacific Ocean, are nocturnal and bury into the seafloor during the day. The animals secrete adhesives through their epithelial glands to completely coat themselves with sand. In cases of danger, they instantaneously release the sandy coat as a sinking decoy to deflect predators. Earlier morphological investigations have shown that the adhesive gland cells of Euprymna scolopes are scattered on the dorsal epidermis. It has been proposed that neutral mucopolysaccharides, secreted by one gland type (goblet cells), are responsible for adhesion, whereas the release of the glue could be caused by acidic mucoproteins produced by ovate cells in the ventral epidermis. The ultrastructural re-investigation of the Euprymna epithelium in this study has indicated the presence of a new gland type (named flask cell), exclusively located in the dorsal epithelium and always neighboured to the known goblet cells. Based on our histochemical observations, the secretory material of the ovate cells does not display a strong reaction to tests for acidic groups, as had been previously assumed. Within the dermis, a large muscle network was found that was clearly distinctive from the normal mantle musculature. Based on our data, an antagonistic gland system, as previously proposed, seems to be unlikely for Euprymna scolopes. We hypothesize that the adhesive secretion is formed by two gland types (goblet and flask cells). The release of the sand coat may occur mechanically, i.e. by contraction of the dermal mantle muscle, and not chemically through the ovate cells.


Assuntos
Secreções Corporais/química , Secreções Corporais/fisiologia , Cefalópodes/fisiologia , Fenômenos Fisiológicos da Pele , Pele/ultraestrutura , Adesividade , Animais
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