RESUMO
This review critically assessed the existence of presbygeusia, i.e., the impairment in taste perception occurring in the elderly, as a natural part of the aging process and its potential clinical implications. Several factors might contribute to age-related taste alterations (TAs), including structural changes in taste buds, alterations in saliva composition, central nervous system changes, and oral microbiota dysbiosis. A comprehensive literature review was conducted to disentangle the effects of age from those of the several age-related diseases or conditions promoting TAs. Most of the included studies reported TAs in healthy elderly people, suggesting that presbygeusia is a relatively frequent condition associated with age-related changes in the absence of pathological conditions. However, the impact of TAs on dietary preferences and food choices among the elderly seems to be less relevant when compared to other factors, such as cultural, psychological, and social influences. In conclusion, presbygeusia exists even in the absence of comorbidities or drug side effects, but its impact on dietary choices in the elderly is likely modest.
Assuntos
Papilas Gustativas , Paladar , Humanos , Idoso , Paladar/fisiologia , Percepção Gustatória/fisiologia , Saliva/química , Saliva/fisiologia , Papilas Gustativas/fisiologia , Preferências AlimentaresRESUMO
BACKGROUND: This study aimed to evaluate the effect of dental caries and oral health of patients on salivary cytokine levels with Hashimoto's thyroiditis (HT). MATERIAL AND METHODS: The study included 30 patients (n = 30) diagnosed with HT. The standardization of the participants was achieved with specific biochemical parameters, and the sociodemographic information of the patients was obtained through anamnesis. A pH meter was employed for salivary pH measurement. After determining the oral problems of the patients, necessary treatments were applied. Following 3 months of treatment, saliva samples were taken to evaluate cytokine levels (TNF-α, IL-6, IL-8, and CRP) and for ELISA analyses. The Wilcoxon test was used for pairwise comparison of nonparametric data, and the Chi-square test was employed to analyze categorical variables at P < 0.05. RESULTS: There was a significant decrease in salivary TNF-α, IL-6, IL-8, and CRP levels between the measurements before and after 3 months of treatment (P < 0.05). In addition, a significant increase was found in salivary pH (P < 0.05). CONCLUSIONS: The salivary cytokine levels decrease and the inflammatory response improves when the inflammation in the periodontal tissues and dental caries is treated.
Assuntos
Cárie Dentária , Doença de Hashimoto , Humanos , Citocinas , Saliva/fisiologia , Fator de Necrose Tumoral alfa , Interleucina-6 , Interleucina-8RESUMO
Saliva substitutes are human-made formulations extensively used in medicine, food, and pharmaceutical research to emulate human saliva's biochemical, tribological, and rheological properties. Even though extensional flows involving saliva are commonly encountered in situations such as swallowing, coughing, sneezing, licking, drooling, gleeking, and blowing spit bubbles, rheological evaluations of saliva and its substitutes in most studies rely on measured values of shear viscosity. Natural saliva possesses stringiness or spinnbarkeit, governed by extensional rheology response, which cannot be evaluated or anticipated from the knowledge of shear rheology response. In this contribution, we comprehensively examine the rheology of twelve commercially available saliva substitutes using torsional rheometry for rate-dependent shear viscosity and dripping-onto-substrate (DoS) protocols for extensional rheology characterization. Even though most formulations are marketed as having suitable rheology, only three displayed measurable viscoelasticity and strain-hardening. Still, these too, failed to emulate the viscosity reduction with the shear rate observed for saliva or match perceived stringiness. Finally, we explore the challenges in creating saliva-like formulations for dysphagia patients and opportunities for using DoS rheometry for diagnostics and designing biomimetic fluids.
Assuntos
Saliva , Humanos , Saliva/fisiologia , Reologia/métodos , ViscosidadeRESUMO
Hydroxyapatite adsorbs various substances, but little is known about the effects on oral bacteria of adsorption onto hydroxyapatite derived from scallop shells. In the present study, we analyzed the effects of adsorption of Streptococcus mutans onto scallop-derived hydroxyapatite. When scallop-derived hydroxyapatite was mixed with S. mutans, a high proportion of the bacterial cells adsorbed onto the hydroxyapatite in a time-dependent manner. An RNA sequencing analysis of S. mutans adsorbed onto hydroxyapatite showed that the upregulation of genes resulted in abnormalities in pathways involved in glycogen and histidine metabolism and biosynthesis compared with cells in the absence of hydroxyapatite. S. mutans adsorbed onto hydroxyapatite was not killed, but the growth of the bacteria was inhibited. Electron microscopy showed morphological changes in S. mutans cells adsorbed onto hydroxyapatite. Our results suggest that hydroxyapatite derived from scallop shells showed a high adsorption ability for S. mutans. This hydroxyapatite also caused changes in gene expression related to the metabolic and biosynthetic processes, including the glycogen and histidine of S. mutans, which may result in a morphological change in the surface layer and the inhibition of the growth of the bacteria.
Assuntos
Durapatita , Streptococcus mutans , Durapatita/farmacologia , Adsorção , Hidroxiapatitas/farmacologia , Histidina/farmacologia , Glicogênio , Saliva/fisiologiaRESUMO
Ticks are important ectoparasites that can vector multiple pathogens. The salivary glands of ticks are essential for feeding as their saliva contains many effectors with pharmaceutical properties that can diminish host immune responses and enhance pathogen transmission. One group of such effectors are microRNAs (miRNAs). miRNAs are short non-coding sequences that regulate host gene expression at the tick-host interface and within the organs of the tick. These small RNAs are transported in the tick saliva via extracellular vesicles (EVs), which serve inter-and intracellular communication. Vesicles containing miRNAs have been identified in the saliva of ticks. However, little is known about the roles and profiles of the miRNAs in tick salivary vesicles and glands. Furthermore, the study of vesicles and miRNAs in tick saliva requires tedious procedures to collect tick saliva. This protocol aims to develop and validate a method for isolating miRNAs from purified extracellular vesicles produced by ex vivo organ cultures. The materials and methodology needed to extract miRNAs from extracellular vesicles and tick salivary glands are described herein.
Assuntos
Vesículas Extracelulares , MicroRNAs , Carrapatos , Animais , Vesículas Extracelulares/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Saliva/fisiologia , Glândulas Salivares/metabolismo , Carrapatos/genéticaRESUMO
BACKGROUND: The human tongue is important in the oral processing of food and in sensory perception. Tongue topography could influence delicate differences in sensory perception. It is hypothesized that tongue surface roughness could alter oral lubrication status and affect perception of smoothness. Fifteen participants with varying levels of tongue surface roughness were recruited and tested. Participants' in situ oral lubrication status without and after consumption of fluid food (milk with varying fat content and maltodextrin solutions with different shear viscosities) was measured. Participants' smoothness sensory scores were also recorded. RESULTS: The in situ friction coefficient (0.299-1.505) was significantly positively correlated with tongue-surface roughness (54.6-140.0 µm) in all types of test fluid samples across participants. Oral lubrication was significantly decreased when participants consumed the test fluid samples compared with no liquid food consumption, for all test fluid sample types (P < 0.05). No significant differences in in situ friction coefficient were found after participants consumed different test fluid samples, and this was mainly attributed to the limited quantities of fluid residuals in the oral cavity after expectoration. Participants whose tongue surface roughness differed did not exhibit significant differences in smoothness perception with different test fluid samples. CONCLUSION: Tongue surface roughness has a strong impact on in situ oral lubrication, and fluid food intake reduces in situ oral lubrication significantly. Saliva film and tongue surface roughness might play greater roles in oral lubrication and smoothness sensory perception if fluid is expectorated after consumption. The association between oral physiology and texture perception still needs further elucidation. © 2021 Society of Chemical Industry.
Assuntos
Percepção Gustatória , Língua/química , Adulto , Animais , Gorduras/química , Gorduras/metabolismo , Feminino , Fricção , Humanos , Lubrificação , Masculino , Leite/química , Leite/metabolismo , Saliva/química , Saliva/fisiologia , Propriedades de Superfície , Língua/fisiologia , Viscosidade , Adulto JovemRESUMO
BACKGROUND & AIMS: Patients with amyotrophic lateral sclerosis (ALS) develop swallowing difficulties with the progression of the disease. The present study aimed at comparing oral function and body composition between ALS patients and healthy controls, and at evaluating which parameters are the most discriminant between both groups. METHODS: We included ALS patients at the start of their multidisciplinary follow-up at the Geneva University Hospitals and healthy age-, gender-, and dental status-matched adults. We assessed the severity of the disease through the ALS Functional Rating Scale and the swallowing difficulties through the EAT-10 score. We performed an intraoral examination of the dental status, and measured chewing performance, bite, lip and tongue force, saliva weight, and body composition. Group comparisons were performed with t-tests or Mann-Whitney tests as appropriate. Linear discriminant analysis was used to determine the most discriminant parameters between groups. RESULTS: Twenty-six ALS patients (bulbar onset: n = 7, median (IQR) ALS Functional Rating Scale: 37 (11)) were included. The ALS patients had a significantly lower chewing performance (p < 0.001), lip force (p < 0.001), tongue force (p = 0.002), saliva weight (p < 0.004) and fat-free mass index (p < 0.001) as compared to the healthy individuals, and a higher EAT-10 score (p < 0.001). In ALS patients, a low chewing performance was correlated with a low bite (r = -0.45, p < 0.05)) and tongue force (r = -0.59, p < 0.05). The most discriminant parameters between both groups, by order of importance, were chewing performance, fat-free mass index and saliva weight and allowed the calculation of a discriminant function. CONCLUSION: Compared to healthy controls, ALS patients have significant alterations of oral function and body composition. The most discriminant parameters between both groups were chewing performance, fat-free mass index and saliva volume. It remains to be demonstrated whether oral parameters predict outcome. CLINICAL TRIAL REGISTRY: clinicaltrials.gov, identifier: NCT01772888.
Assuntos
Esclerose Lateral Amiotrófica/fisiopatologia , Composição Corporal , Transtornos de Deglutição/fisiopatologia , Deglutição , Mastigação , Idoso , Esclerose Lateral Amiotrófica/complicações , Força de Mordida , Estudos de Casos e Controles , Transtornos de Deglutição/etiologia , Feminino , Humanos , Lábio/fisiopatologia , Masculino , Pessoa de Meia-Idade , Saliva/fisiologia , Índice de Gravidade de Doença , Língua/fisiopatologiaRESUMO
To evaluate ICIs related dry eye and dry mouth in nivolumab therapy, 24 patients receiving nivolumab (group 1), 30 patients in remission without treatment for 6 months (group 2), 30 healthy participants (group 3) were cross-sectionally examined. Schirmer's 1, 2, TSH blood tests, serological analysis, salivary flow scintigraphy and minor-salivary gland biopsy were performed. Schirmer's tests were performed with anesthetic (1) and without anesthetic (2). Schirmer's scores were lower in group 1 with more frequent reduced tear production (p < 0.001). TSH levels negatively correlated with Schirmer's scores. Functional insufficiency was detected by salivary flow scintigraphy in 7 out of 10 patients with Schirmer's test positivity. In Schirmer's positive patients, lymphocytic sialadenitis was confirmed in 4 patients (focus score > 1) and CD4 T lymphocyte precipitation was observed in 6 patients. Nivolumab therapy may be associated with ICIs related immune sicca.
Assuntos
Síndromes do Olho Seco/induzido quimicamente , Inibidores de Checkpoint Imunológico/efeitos adversos , Nivolumabe/efeitos adversos , Xerostomia/induzido quimicamente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saliva/efeitos dos fármacos , Saliva/fisiologia , Tireotropina/sangue , Adulto JovemRESUMO
The present investigation tries to reflect histochemical and stereological properties of the parotid gland (PG) and sublingual gland (SLG) in the Caucasian squirrel. Totally, five male Caucasian squirrels were used. The glands were examind histochemical using PAS, Alcian blue (AB, pH = 2.5) and Aldehyde fucshin (AF) stainings. Total volume of the glands, acini, ducts as well as total length of ducts were estimated using streological procedures. The PG had a unique morphology and were connected to each other with an intermediated isthmus. The SLG was oval-shaped. Serous acini of PG exhibited strong, negative and weak reaction with AF, AB and PAS, respectively. While, mucous acini of SLG showed positive staining for AB and PAS, and negative staining for AF. The ductal system was consisted of intercalated (Id), striated (SD) and excretory ducts (Ed). The Sd in PG was lined with simple cuboidal to the columnar epithelium, while it was lined with simple cuboidal epithelium in SLG. The Ed was lined with stratified cuboidal epithelium in both glands. The striated duct was longest duct in both glands, the excretory and intercalated ducts were the shortest ones in PG and SLG, respectively. The maximum total volume in both gland were blonged to the acini and straited ducts. It concluded that PG and SLG in the Caucasian squirrel have some distinct structural properties in comparison to other rodents and mammalis species.
Assuntos
Histocitoquímica/métodos , Glândula Parótida/patologia , Glândula Sublingual/patologia , Animais , Masculino , Mucinas/metabolismo , Glândula Parótida/anatomia & histologia , Saliva/fisiologia , Sciuridae , Glândula Sublingual/anatomia & histologiaRESUMO
The aim of this study was to investigate the impact of oral impairment on chewing behaviour, food bolus properties and food comfortability during elderly consumption of model cheeses. Seventy-two elderly persons (aged 66 to 88) was recruited and classified into two groups according to dental status (poor vs. satisfactory). They showed a wide range of salivary flow rates whatever their dental status (stimulated: 0.2-3.8 mL min-1, resting: 0.1-0.8 mL min-1). Standardized bites of four model cheeses with an identical composition but different textures (soft, hard, processed and whipped) were tested. The time and number of chewing cycles required to form a bolus were measured. The rheological properties of the bolus were studied, as was saliva moistening. Food comfortability was assessed by means of a questionnaire composed of 5 sections (1-oral comfort, 2-bolus formation, 3-pain, 4-texture and 5-flavour perception). The chewing parameters measured were not modified by the oral health. However, elderly with poor dentition formed harder boluses than elderly with satisfactory dentition. Moreover, for elderly with poor dentition, the quantity of saliva incorporated into the bolus was correlated with the stimulated salivary flow rate, which was not the case for elderly with satisfactory dentition. General oral comfort and its different attributes were poorly associated with the oral health of the elderly. A multifactorial analysis performed on an average cheese showed that food comfortability is independent of changes in the hardness and moistening of the bolus, regardless of dental status. In particular, poor dental status increases the hardness of the bolus without modifying its comfortability.
Assuntos
Queijo , Dentição , Avaliação Geriátrica/métodos , Nível de Saúde , Mastigação/fisiologia , Saúde Bucal/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Saliva/fisiologia , Inquéritos e Questionários , Paladar/fisiologiaRESUMO
BACKGROUND: Nicotine addiction is associated with nicotine absorption from the buccal mucosa, and it is stated that the main factor that determines nicotine absorption is saliva pH. In the literature, the effects of changes in saliva pH values after eating and drinking on smoking desire in smokers were not questioned. AIM: To show the effect of saliva pH changes on smoking desire. The secondary aim was to show the impact of coffee and water drinking on saliva pH and smoking on oral-dental health (oral hygiene and gingival bleeding). STUDY DESIGN: Case-control study. METHODS: A questionnaire was administered that included "Sociodemographic Data Form" and smoking history and Fagerström Test for Nicotine Dependence (FTND). Oral and dental examinations were performed with mirror sonds and using oral hygiene standard Silness and Leöe plaque index and DMFT Index (Index of Decayed Missing or Filled Teeth). Untreated saliva samples were taken, and baseline saliva flow rate and pH values were measured. To assess pH changes, saliva pH was remeasured after sugar-free instant coffee and water consumption. Smoking desire was evaluated with the Visual Analog Scale (VAS). RESULTS: In this study, 24 (55.8%) females and 19 (44.2%) males were among the 43 smoking and 39 nonsmoking cases. Smoking was significantly associated with poor oral hygiene (in smokers 4.71 (±1.40), in non-smokers 2.30 (±1.59); P < .01). DMFT index was higher in smokers than in non-smokers (in smokers 6.45 (±3.69), in non-smokers 3.87 (±2.67); P < .01). Gingival bleeding was more prevalent in smokers (0.68 (±0.76)) than non-smokers (1.20 (±0.90); P = .009). Salivary flow rates were lower in smokers (in smokers 2.56 (±1.34), in non-smokers 3.00 (±1.22), P = .06). In both groups, pH values increased after coffee consumption and decreased after water; in smokers basal: 6.67 (±0.41), pH coffee: 6.93 (±0.36), pH water: 6.85 (±0.33); in non-smokers pH basal: 6.84 (±0.37), pH coffee: 7.02 (±0.37), pH water: 6.97 (±0.31), P < .01. The VAS values of smokers at basal 4.73 (±3.21); P < 0.01, after coffee consumption 4.91 (±3.08); P < .01, and after water 3.15 (±2.72); P < .01. CONCLUSION: The saliva pH increased after coffee consumption and decreased after drinking water. Besides, VAS values decreased significantly after drinking water. The results suggest that a simple behavior such as drinking water may be used in conjunction with behavioral and cognitive therapies to pursue smoking cessation.
Assuntos
Concentração de Íons de Hidrogênio , Boca/química , Fumar/psicologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Boca/fisiopatologia , Saliva/química , Saliva/fisiologia , Inquéritos e QuestionáriosRESUMO
Lichen planus is the most common skin disease that affects the oral mucosa. Oral Lichen Planus is a T-cell-mediated autoimmune disorder. In the current study, for the first time, an oral cavity condition in skin patch tests with adding saliva is simulated. In addition, the patch results are compared with healthy subjects. Forty-one OLP patients and 63 healthy subjects were enrolled in the study. All participants were provided with patch tests, including allergens, in combination with saliva in chambers. Allergens from the European baseline (standard) series selected according to the most prevalent positive results in the previous study were applied. Positive results of Mercury and Cobalt tests were significantly higher in the case group. In this study, the differentiation of patients with lichen planus and lichenoid was identified according to the Van der Meij & Van der Waal criteria. The patch test was conducted for healthy individuals as well. The most important of all was the use of patients' saliva in the patch test, done for the first time in this field. In the case of OLP, a patch test can help identify positive reactions to dental materials; thus, the replacement of dental restorations may be needed.
Assuntos
Materiais Dentários/efeitos adversos , Líquen Plano Bucal/diagnóstico , Testes do Emplastro/métodos , Saliva/fisiologia , Adulto , Feminino , Humanos , Líquen Plano Bucal/etiologia , Líquen Plano Bucal/imunologia , MasculinoRESUMO
Resistance (R) genes usually compete in a coevolutionary arms race with reciprocal effectors to confer strain-specific resistance to pathogens or herbivorous insects. Here, we investigate the specificity of SLI1, a recently identified R gene in Arabidopsis that encodes a small heat shock-like protein involved in resistance to Myzus persicae aphids. In a panel with several aphid and whitefly species, SLI1 compromised reproductive rates of three species: the tobacco aphid M. persicae nicotianae, the cabbage aphid Brevicoryne brassicae and the cabbage whitefly Aleyrodes proletella. Electrical penetration graph recording of aphid behaviour, revealed shorter salivations and a 3-to-5-fold increase in phloem feeding on sli1 loss-of-function plants. The mustard aphid Lipaphis erysimi and Bemisia tabaci whitefly were not affected by SLI1. Unlike the other two aphid species, L. erysimi exhibited repetitive salivations preceding successful phloem feeding, indicating a role of salivary effectors in overcoming SLI1-mediated resistance. Microscopic characterization showed that SLI1 proteins localize in the sieve tubes of virtually all above- and below-ground tissues and co-localize with the aphid stylet tip after penetration of the sieve element plasma membrane. These observations reveal an unconventional R gene that escapes the paradigm of strain specificity and confers broad-spectrum quantitative resistance to phloem-feeding insects.
Assuntos
Afídeos/fisiologia , Proteínas de Arabidopsis/genética , Arabidopsis/fisiologia , Chaperonas Moleculares/genética , Floema/fisiologia , Animais , Proteínas de Arabidopsis/metabolismo , Comportamento Alimentar , Regulação da Expressão Gênica de Plantas , Hemípteros/fisiologia , Herbivoria , Chaperonas Moleculares/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Caules de Planta/genética , Caules de Planta/metabolismo , Plantas Geneticamente Modificadas , Saliva/fisiologiaRESUMO
Submandibular glands have essential functions in taste, mastication, swallowing, and digestion. Submandibular gland hypofunction is prevalent in the elderly, impairing the patients' quality of life. Current clinical treatment strategies have not decelerated or reversed the pathological process of submandibular gland hypofunction. Therefore, novel restoration strategies should be explored. However, studies on the mechanism of aging-related submandibular gland hypofunction remain very limited. The role of the TGF-ß/Smad pathway in fibrosis has been studied in other organs. Therefore, this study aimed to elucidate the role of TGF-ß/Smad signaling in the aging-related submandibular gland hypofunction. The results showed that Smad7 knockout in mice decreased the salivary flow rate. H&E, Masson trichrome, and immunohistochemistry staining of MCP-1 and α-SMA showed that Smad7 knockout in mice resulted in lymphocytic infiltration, acinar cell atrophy, and interstitial fibrosis. The Western blotting of collagen I and III also confirmed extensive fibrosis. We then found that Smad7 depletion resulted in the TGF-ß-mediated fibrosis via mir-21, mir-29, and np_5318, and NFκB-driven inflammation activation. This study confirmed the inhibitory role of Smad7 in the aging-related submandibular gland hypofunction. Therefore, it provided a promising treatment target for aging-related dysfunction and sialadenitis of submandibular gland.
Assuntos
Envelhecimento/fisiologia , Proteína Smad7/metabolismo , Glândula Submandibular/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Fibrose , Camundongos Endogâmicos , Camundongos Knockout , Saliva/fisiologia , Proteína Smad7/genética , Glândula Submandibular/metabolismo , Glândula Submandibular/fisiopatologiaRESUMO
Wound healing is a complex and important physiological process that maintains the integrity of skin after various injuries. Abnormal wound healing, especially of chronic wounds, impairs normal physical function. Therefore, the search for effective and safe healing agents is one of the main concerns. Histatins are histidine-rich low molecular weight peptides that are expressed in the saliva of both humans and higher primates. Histatins have two main biological effects, cell stimulation and bacteria killing, with the former playing an important role in wound healing by promoting epithelial cell and fibroblast migration and angiogenesis and enhancing the re-epithelialization of the wounded area. Because of these biological effects, histatins have been shown to be promising agents of improved wound healing. Histatins are categorized into many subtypes, of which histatin 1 and its hydrolysates are the most effective in promoting wound healing. This review addresses the bioactivity of histatins in wound healing, such as their stimulatory effects on epithelial cells and fibroblasts, and elucidates the possible mechanisms by which histatin subtypes induce their biological effects.
Assuntos
Histatinas/farmacologia , Cicatrização/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Histatinas/fisiologia , Humanos , Saliva/química , Saliva/fisiologia , Pele/lesõesRESUMO
The tick Rhipicephalus microplus is a harmful parasite of cattle that causes considerable economic losses to the cattle breeding industry. Although R. microplus saliva (Rm-saliva) contains several immunosuppressants, any association between Rm-saliva and the expression of immunoinhibitory molecules, such as programmed death (PD)-1 and PD-ligand 1 (PD-L1), has not been described. In this study, flow cytometric analyses revealed that Rm-saliva upregulated PD-1 expression in T cells and PD-L1 expression in CD14+ and CD11c+ cells in cattle. Additionally, Rm-saliva decreased CD69 expression in T cells and Th1 cytokine production from peripheral blood mononuclear cells. Furthermore, PD-L1 blockade increased IFN-γ production in the presence of Rm-saliva, suggesting that Rm-saliva suppresses Th1 responses via the PD-1/PD-L1 pathway. To reveal the upregulation mechanism of PD-1/PD-L1 by Rm-saliva, we analyzed the function of prostaglandin E2 (PGE2), which is known as an inducer of PD-L1 expression, in Rm-saliva. We found that Rm-saliva contained a high concentration of PGE2, and PGE2 treatment induced PD-L1 expression in CD14+ cells in vitro. Immunohistochemical analyses revealed that PGE2 and PD-L1 expression was upregulated in tick-attached skin in cattle. These data suggest that PGE2 in Rm-saliva has the potential to induce the expression of immunoinhibitory molecules in host immune cells.
Assuntos
Antígeno B7-H1/metabolismo , Interações Hospedeiro-Parasita , Tolerância Imunológica , Receptor de Morte Celular Programada 1/metabolismo , Rhipicephalus/fisiologia , Saliva/fisiologia , Picadas de Carrapatos/veterinária , Animais , Bovinos/metabolismo , Bovinos/parasitologia , Dinoprostona/metabolismo , Citometria de Fluxo , Redes e Vias Metabólicas , Células Th1/fisiologia , Picadas de Carrapatos/imunologia , Picadas de Carrapatos/metabolismoRESUMO
Mud nests built by swallows (Hirundinidae) and phoebes (Sayornis) are stable granular piles attached to cliffs, walls, or ceilings. Although these birds have been observed to mix saliva with incohesive mud granules, how such biopolymer solutions provide the nest with sufficient strength to support the weight of the residents as well as its own remains elusive. Here, we elucidate the mechanism of strong granular cohesion by the viscoelastic paste of bird saliva through a combination of theoretical analysis and experimental measurements in both natural and artificial nests. Our mathematical model considering the mechanics of mud nest construction allows us to explain the biological observation that all mud-nesting bird species should be lightweight.
Assuntos
Comportamento de Nidação/fisiologia , Passeriformes/fisiologia , Saliva/fisiologia , Andorinhas/fisiologia , Animais , Modelos TeóricosRESUMO
MUC5B and MUC7 salivary mucins are reported to inhibit HIV-1 entry into target cells in vitro; however, their relative inhibitory potencies have not been quantitively compared. There is also conflicting evidence regarding whether HIV-1 infection diminishes mucins' inhibitory efficacy. We explored the effect of donor HIV-1 status upon the anti-HIV-1 potency of purified MUC5B and MUC7 while comparing their relative inhibitory potential using a pseudovirus-based neutralization assay. HIV status of sample donors had no detectable effect on HIV-1 inhibition by salivary mucins. MUC5B (median IC50 50 µg/ml, IQR 10-116 µg/ml) exhibited significantly more potent HIV-1 inhibition than MUC7 (median IC50 458 µg/ml, IQR 192->2000 µg/ml; Mann-Whitney U p < 0.0001). We suggest that larger size, gel-forming properties and extensive glycosylation of MUC5B allow more effective binding and aggregation of viral particles. MUC5B is also more abundant in the saliva and is therefore likely to make a substantially greater contribution to it's anti-HIV-1 properties.
Assuntos
HIV-1/fisiologia , Mucina-5B/fisiologia , Mucinas/fisiologia , Saliva/química , Proteínas e Peptídeos Salivares/fisiologia , Adulto , Fármacos Anti-HIV , Linhagem Celular , Sobrevivência Celular , Glicosilação , Infecções por HIV/metabolismo , HIV-1/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Mucina-5B/química , Mucina-5B/isolamento & purificação , Mucina-5B/farmacologia , Mucinas/química , Mucinas/isolamento & purificação , Mucinas/farmacologia , Saliva/fisiologia , Proteínas e Peptídeos Salivares/química , Proteínas e Peptídeos Salivares/isolamento & purificação , Proteínas e Peptídeos Salivares/farmacologia , Pseudotipagem Viral , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Adulto JovemRESUMO
Thermoresponsive cell culture plates release cells as confluent living sheets in response to small changes in temperature, with recovered cell sheets retaining functional extracellular matrix proteins and tight junctions, both of which indicate formation of intact and functional tissue. Our recent studies demonstrated that cell sheets are highly effective in promoting mouse submandibular gland (SMG) cell differentiation and recovering tissue integrity. However, these studies were performed only at early time points and extension of the observation period is needed to investigate duration of the cell sheets. Thus, the goal of this study was to demonstrate that treatment of wounded mouse SMG with cell sheets is capable of increasing salivary epithelial integrity over extended time periods. The results indicate that cell sheets promote tissue organization as early as eight days after transplantation and that these effects endure through Day 20. Furthermore, cell sheet transplantation in wounded SMG induces a significant time-dependent enhancement of cell polarization, differentiation and ion transporter expression. Finally, this treatment restored saliva quantity to pre-wounding levels at both eight and twenty days post-surgery and significantly improved saliva quality at twenty days post-surgery. These data indicate that cell sheets engineered with thermoresponsive cell culture plates are useful for salivary gland regeneration and provide evidence for the long-term stability of cell sheets, thereby offering a potential new therapeutic strategy for treating hyposalivation.