Expression of a Lipocalin in Human Nasal Mucosa

A 19 kDa soluble protein was purified from human nasal mucus. Its N-terminal amino-acid sequence appeared to be identical to that of a lipocalin synthesised both in lachrymal glands and in von Ebner's glands (VEG) of circumvallate papillae. In order to verify whether this protein was synthesised in the nasal cavity or was the result of tear contamination, we adopted an immunohistochemical approach. Polyclonal antibodies, raised against a primate VEG protein, were used on sections of human nasal mucosa obtained from surgery. The results clearly indicate that the protein is synthesised in sero-mucous glands underlying the respiratory ciliated epithelium. Although ligand-binding experiments with some odorant molecules have given negative results, we cannot exclude a role of odorant solubiliser and carrier for this protein.     

Development of the Olfactory Epithelium and Nasal Glands in TMEM16A-/- and TMEM16A+/+ Mice

TMEM16A/ANO1 is a calcium-activated chloride channel expressed in several types of epithelia and involved in various physiological processes, including proliferation and development. During mouse embryonic development, the expression of TMEM16A in the olfactory epithelium is dynamic. TMEM16A is expressed at the apical surface of the entire olfactory epithelium at embryonic day E12.5 while from E16.5 its expression is restricted to a region near the transition zone with the respiratory epithelium. To investigate whether TMEM16A plays a role in the development of the mouse olfactory epithelium, we obtained the first immunohistochemistry study comparing the morphological properties of the olfactory epithelium and nasal glands in TMEM16A^-/- and TMEM16A^+/+ littermate mice. A comparison between the expression of the olfactory marker protein and adenylyl cyclase III shows that genetic ablation of TMEM16A did not seem to affect the maturation of olfactory sensory neurons and their ciliary layer. As TMEM16A is expressed at the apical part of supporting cells and in their microvilli, we used ezrin and cytokeratin 8 as markers of microvilli and cell body of supporting cells, respectively, and found that morphology and development of supporting cells were similar in TMEM16A^-/- and TMEM16A^+/+ littermate mice. The average number of supporting cells, olfactory sensory neurons, horizontal and globose basal cells were not significantly different in the two types of mice. Moreover, we also observed that the morphology of Bowman’s glands, nasal septal glands and lateral nasal glands did not change in the absence of TMEM16A. Our results indicate that the development of mouse olfactory epithelium and nasal glands does not seem to be affected by the genetic ablation of TMEM16A.     

Role of the Lymphoreticular System in Prion Neuroinvasion from the Oral and Nasal Mucosa

Prion neuroinvasion from peripheral tissues involves agent replication in the lymphoreticular system (LRS) prior to entry into the nervous system. This study investigated the role of the LRS in prion neuroinvasion from the oral and nasal mucosa in wild-type and immunodeficient mice and in hamsters infected with the HY and DY strains of the transmissible mink encephalopathy (TME) agent. Following inoculation at neural sites, all hosts were susceptible to prion disease and had evidence of prion infection in the brain, but infection of the LRS was found only in scrapie-infected wild-type mice and HY TME-infected hamsters. In the LRS replication-deficient models, prion neuroinvasion was not observed following intraperitoneal or oral inoculation. However, immunodeficient mice, which have impaired follicular dendritic cells, were susceptible to scrapie following intratongue and intranasal inoculation despite the absence of PrP^Sc in the tongue or the nasal cavity. For DY TME, hamsters were susceptible following intratongue but not intranasal inoculation and PrP^Sc was limited to nerve fibers of the tongue. These findings indicate that neuroinvasion from the tongue and nasal cavity can be independent of LRS infection but neuroinvasion was partially dependent on the strain of the prion agent and/or the host species. The paucity of PrP^Sc deposition in the oral and nasal mucosa from LRS replication-deficient hosts following neuroinvasion from these tissues suggests an infection of nerve fibers that is below the threshold of PrP^Sc detection and/or the transport of the prion agent along cranial nerves without agent replication.In natural and experimental prion infections originating in the periphery, prion agent replication in the lymphoreticular system (LRS) precedes agent entry and spread in the peripheral nervous system. In the LRS, follicular dendritic cells (FDCs) are the major target of prion infection, and blocking or reversing FDC maturation can prevent scrapie agent replication in the LRS (25, 26, 28, 30, 32). Other migrating cell populations may also influence the progression of experimental prion disease (27, 36). From the LRS, centripetal spread of the prion agent to the spinal cord or brain occurs by spread along nerve fibers of the peripheral nervous system. In the central nervous system, prion agent replication can induce neurodegeneration and disease after an incubation period that can last from weeks to years. For example, in lambs from flocks with endemic scrapie, agent replication is initially detected in the gut-associated lymphoid tissues prior to proximal and distal spread in the LRS, infection of peripheral nerves that innervate the LRS, and subsequent spread to the spinal cord (19, 42). In addition, scrapie agent infection of the vagal nerve, which innervates many peripheral organs including the digestive tract, results in axonal transport directly to the dorsal motor nucleus of the vagus in the brain stem (29, 41). The role of scrapie infection in the LRS in the latter pathway of neuroinvasion is unknown. A similar pathway of prion neuroinvasion occurs in mule deer experimentally infected with the chronic wasting disease agent with the exception that early infection is also established in the lymph nodes of the upper gastrointestinal tract (37, 38). Recent studies indicate that a similar pathway of neuroinvasion occurs in natural and experimental bovine spongiform encephalopathy (BSE) following oral exposure except that agent replication in the LRS is greatly reduced and appears restricted to portions of the gut-associated lymphoid tissues (13, 20, 39).There are natural prion diseases in sheep and cattle that do not exhibit the typical distribution of the prion agent in the brain and LRS that are presumably acquired via oral prion exposure (5, 33). The absence of the abnormal isoform of the prion protein, PrP^Sc, in the LRS and dorsal motor nucleus of the vagus in atypical scrapie and the H type or L type of BSE raises the question as to whether these cases are due to infection by an alternate route(s) other than ingestion or whether these cases have an etiology that is distinct from that of acquired prion diseases. Direct prion infection of nerve fibers or terminals in highly innervated tissues, such as the mucosa in the head, has been suggested to represent potential sites of prion agent entry that would not require prior agent replication in the LRS (4, 12, 31). The presence of scrapie or BSE infection in the retina, sensory fibers of the tongue, and nasal mucosa of sheep, goat, and/or cattle suggests that the eye, tongue, or nasal cavity could be alternate sites of prion agent entry into hosts (8, 11, 15, 16, 40). Experimental prion inoculation at these mucosal sites can cause prion disease and in some cases rapid neuroinvasion (4, 9, 17, 18). Another explanation for this distribution of infection is that centrifugal spread of the prion agent away from the brain and along cranial nerves could serve as a pathway for prion infection and accumulation in these mucosal tissues (4, 10, 43).In this work, we investigated the role of the LRS in prion neuroinvasion from the oral and nasal cavities. In order to investigate neuroinvasion following neural and extraneural routes of inoculation in which prion replication is blocked in the LRS, we used two rodent models for prion infection. In muMT mice, which lack mature B cells, and in lymphotoxin-α (LTα) null mice, FDCs do not undergo maturation, and as a result, these mice do not develop clinical disease following intraperitoneal inoculation of the scrapie agent but are susceptible following direct inoculation into the brain (23, 30). In a second model, the HY and DY strains of the transmissible mink encephalopathy (TME) agent were used to investigate neuroinvasion in Syrian hamsters. The HY and DY TME agents can replicate in the nervous system, but the DY TME agent does not replicate in the LRS, and therefore, the DY TME agent is not pathogenic following intraperitoneal (i.p.) inoculation (2, 3). Following intratongue (i.t.) or intranasal (i.n.) inoculation, prion neuroinvasion was independent of scrapie agent replication in the LRS of immunodeficient mice, but evidence for scrapie infection of peripheral nerve fibers or olfactory neurons at these mucosa was lacking. In hamsters, i.t. inoculation of the HY or DY TME agent resulted in PrP^Sc deposition in nerve fibers and prion disease, but only the HY TME agent caused disease following i.n. inoculation. These findings suggest that neuroinvasion from the oral and nasal mucosa in LRS replication-deficient rodents can be independent of LRS infection, but the paucity of PrP^Sc at these mucosal sites of exposure in immunodeficient mice and DY TME-infected hamsters suggests that neuroinvasion is due to either a low-level prion infection of the nervous system at the site of inoculation or transport of the prion agent in axons in the absence of agent replication at the site of prion entry. These findings indicate that these mucosal tissues may not exhibit early evidence of infection and therefore will prove difficult to identify as a portal for agent entry.     

变应性鼻炎模型小鼠鼻黏膜的形态学观察

目的:建立小鼠变应性鼻炎模型,观察小鼠鼻腔黏膜组织的重塑情况。方法:20只BALB/c小鼠被随机分为致敏组和对照组,使用卵清蛋白(OVA)诱导建立小鼠变应性鼻炎模型。通过HE染色观察小鼠鼻黏膜的大体重塑情况,吉姆萨染色观察嗜酸性粒细胞,阿辛蓝-过碘酸-希夫染色观察杯状细胞;酶联免疫吸附(ELISA)法检测小鼠血清中白细胞介素-4(IL-4)的水平。结果:小鼠变应性鼻炎模型的生物学行为评分为6.5±1.3,提示造模成功。与对照组相比,致敏组鼻腔黏膜出现上皮细胞脱落、坏死,杯状细胞增生,鳞状上皮化生,固有层和黏膜下层腺体增生、血管扩张,组织水肿,固有层内可见特征性的嗜酸性粒细胞浸润,造模后鼻腔黏膜结构存在重塑。致敏组小鼠鼻黏膜嗜酸性粒细胞计数及杯状细胞计数分别为(26.4±5.72)和(24.14±3.12),而对照组分别是(8.31±2.42)和(9.41±1.22),两组比较均具有统计学差异(P0.05);致敏组血清中白细胞介素4(IL-4)水平为(18.9±3.1)pg/ml,对照组为(8.3±1.4)pg/ml,致敏组显著高于对照组,差异有统计学意义(P0.05)。结论:通过卵清蛋白诱导建立的小鼠变应性鼻炎模型鼻腔黏膜存在组织重塑。     

Study of an Amoeboflagellate Isolated from the Nasal Mucosa of Man

ABSTRACT. This paper examines the biology, morphology, and pathogenicity for mice of an amoeboflagellate isolated from human nasal mucosa. The biological and morphological relationships of this isolate with the amoebae (Lobosea) and the true slime molds (Eumycetoza) are discussed though the taxonomic affinities of the organism have not been determined.     

Vascularization and Development of Cytoarchitectonics in the Human Neocortical Rudiment

The development of cytoarchitectonics of the brain rudiments in mammals is accompanied by the formation of an intracerebral vascular network. The relationship between these two processes is insufficiently clear. We studied the development of blood vessels and cytoarchitectonics in the neocortical rudiment of 6- to 13-week old human embryos. The light and electron microscopy methods were used, as well as histochemical visualization of NADPH-diaphorase in the vessel cells. The endothelium proliferation was evaluated using antibodies to proliferating cell nuclear antigen. Starting from week 8 of development, the tangentially oriented vessels formed a intraneural network in the ventricular zone of the rudiment, which appears to restrict the motility of neuroepithelial cells. The basal membrane was initially absent, and the neuroepithelial cells were in direct contact with the endothelial cells. During week 9 of development, the tangentially oriented vessels appeared in the intermediate zone. Formations similar to glial legs with short regions of the basal membrane adjoined the walls of inter- and intraneural vessels (note that, according to the published data, glial fibrillary acidic protein is not yet visualized at this stage). Angioarchitectonics depended little on the cell population density in different zones of the rudiment; specifically, the cortical plate did not contain tangentially oriented vessels until week 12–13 of development. The data we obtained suggest that the blood vessels fulfill a special morphogenetic function in the developing neocortex.     

Characterization of Isolates of Acanthamoeba from the Nasal Mucosa and Cutaneous Lesions of Dogs

Acanthamoeba spp. are free-living amoebae that are ubiquitously distributed in the environment and can cause encephalomyelitis in animals and humans. The factors that contribute to Acanthamoeba infections include parasite biology, genetic diversity, environmental spread, and host susceptibility. The aim of the present study was to characterize isolates of Acanthamoeba from the nasal mucosa and cutaneous lesions of dogs in order to access the occurence and pathogenicity of these organisms in this animal group. We studied 13 isolates of Acanthamoeba confirmed by polymerase chain reaction. They were sequenced, the genotype was determined, and their potential of pathogenicity was evaluated.     

Effect of Lipopolysaccharide on Glucocorticoid Receptor Function in Control Nasal Mucosa Fibroblasts and in Fibroblasts from Patients with Chronic Rhinosinusitis with Nasal Polyps and Asthma

BackgroundChronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic inflammatory disease of the upper airways frequently associated with asthma. Bacterial infection is a feature of CRSwNP that can aggravate the disease and the response to glucocorticoid treatment.ObjectiveWe examined whether the bacterial product lipopolysaccharide (LPS) reduces glucocorticoid receptor (GR) function in control nasal mucosa (NM) fibroblasts and in nasal polyp (NP) fibroblasts from patients with CRSwNP and asthma.MethodsNP (n = 12) and NM fibroblasts (n = 10) were in vitro pre-incubated with LPS (24 hours) prior to the addition of dexamethasone. Cytokine/chemokine secretion was measured by ELISA and Cytometric Bead Array. GRα, GRβ, mitogen-activated protein-kinase phosphatase-1 (MKP-1) and glucocorticoid-induced leucine zipper (GILZ) expression was measured by RT-PCR and immunoblotting, GRα nuclear translocation by immunocytochemistry, and GRβ localization by immunoblotting. The role of MKP-1 and GILZ on dexamethasone-mediated cytokine inhibition was analyzed by small interfering RNA silencing.ResultsPre-incubation of nasal fibroblasts with LPS enhanced the secretion of IL-6, CXCL8, RANTES, and GM-CSF induced by FBS. FBS-induced CXCL8 secretion was higher in NP than in NM fibroblasts. LPS effects on IL-6 and CXCL8 were mediated via activation of p38α/β MAPK and IKK/NF-κB pathways. Additionally, LPS pre-incubation: 1) reduced dexamethasone’s capacity to inhibit FBS-induced IL-6, CXCL8 and RANTES, 2) reduced dexamethasone-induced GRα nuclear translocation (only in NM fibroblasts), 3) did not alter GRα/GRβ expression, 4) decreased GILZ expression, and 5) did not affect dexamethasone’s capacity to induce MKP-1 and GILZ expression. MKP-1 knockdown reduced dexamethasone’s capacity to suppress FBS-induced CXCL8 release.ConclusionThe bacterial product LPS negatively affects GR function in control NM and NP fibroblasts by interfering with the capacity of the activated receptor to inhibit the production of pro-inflammatory mediators. This study contributes to the understanding of how bacterial infection of the upper airways may limit the efficacy of glucocorticoid treatment.     

生物磁学在鸟类定向研究中的进展

地球上广泛存在的地磁场能够为导航提供可靠的信息,因此很多鸟类在迁徙和归巢过程中都使用地磁信息来保证航行方向的正确,在迁徙的鸟类中已经发现有18种是利用地磁罗盘进行定向和导航的。本文从鸟类使用的磁罗盘、航行地图以及磁感应机制等几方面阐述了目前在鸟类生物磁学方面的研究进展。     

中国鸟类生态学的发展与现状

中国鸟类生态学的发展可分三个阶段 :2 0世纪 3 0年代至 5 0年代末的萌芽期 ;60年代初至 70年代末的成长期 ;80年代以来的蓬勃发展期。 1 990年以来 ,繁殖是我国鸟类生态学的最主要研究内容 ,论文数量比例占 2 3 5 3 % ;行为、栖息地、群落和迁徙等方面的研究有明显增长 ;鸟类食性研究的关注程度下降。本文对繁殖、行为、栖息地、种群和群落内容研究现状进行详细分析 ,并提出了今后中国鸟类生态学研究与发展应予以关注的问题     

鼻内镜术前应用枸地氯雷他定对慢性鼻窦炎的治疗效果及对患者嗅觉功能和鼻黏膜形态的影响

摘要 目的：探讨鼻内镜术前应用枸地氯雷他定对慢性鼻窦炎的治疗效果及对患者嗅觉功能和鼻黏膜形态的影响。方法：选取我院2019年1月到2022年12月收治的80例慢性鼻窦炎患者作为研究对象,分为观察组与对照组,各40例。对照组患者采取单纯鼻内镜手术治疗,观察组患者在术前应用枸地氯雷他定治疗1个月后再行鼻内镜手术,对比两组患者的临床治疗效果,治疗前后炎症因子水平,内镜下鼻粘膜形态量化评分,嗅觉功能与糖精试验时间。结果：两组患者治疗总有效率对比无差异（P＞0.05）;治疗后两组患者IL-6、IL-1、TNF-α相关炎症因子水平均降低,且观察组较对照组低（P＜0.05）;治疗前两组患者鼻漏、结痂、瘢痕、黏膜水肿、息肉、脓性分泌物等情况内镜下鼻粘膜形态量化评分对比无明显差异（P＞0.05）,治疗后两组患者鼻漏、结痂、瘢痕、黏膜水肿、息肉、脓性分泌物等情况内镜下鼻粘膜形态量化评分均降低,且观察组较对照组低（P＜0.05）;治疗前两组患者嗅觉识别阈值、糖精试验时间对比无明显差异（P＞0.05）,治疗后两组患者嗅觉识别阈值、糖精试验时间均降低,且观察组低于对照组（P＜0.05）。结论：鼻内镜术前应用枸地氯雷他定对慢性鼻窦炎具有显著临床疗效,同时能够降低患者术后炎症因子水平,改善鼻黏膜形态,提升纤毛运动功能与嗅觉功能,值得临床应用推广。     

Vascularization of the thymus in the duck

The arrangement and the blood of Thymus lobes were shown by intra-vasal injection of Indian ink or Neoprene Latex. The origin and the distribution of the arteries were studied within thymic lobe and until the final branches represented by endolobulare capillaries. These branches represent the origin of the vein of the thymic lobe.     

Vascularization of the corpus callosum in humans

The blood supply of the corpus callosum is studied in 20 brains by injecting the vascular system with gelatinous Indian ink. The arterial vascularization derives mainly from the anterior cerebral arteries, accessed from the median artery of the corpus callosum or from the terminal and choroidal branches of the posterior cerebral arteries. The various arteries give off perforating branches which are direct or indirect, short, of middle length or long. All these arteries concentrate on the peripheral wall of the corpus callosum. Inside of it these various arteries give off numerous terminal and collateral branches running between the nervous fibres and forming a characteristic vascular network which nourishes the capillary network. The venous vascularization of the corpus callosum is tributary to the deep venous system of the brain and concentrates on the central wall of the commissure.     

The Development of Nasal Polyp Disease Involves Early Nasal Mucosal Inflammation and Remodelling

Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by both a chronic inflammation and tissue remodelling; as indicated by extracellular matrix protein deposition, basement membrane thickening, goblet cell hyperplasia and subepithelial edema, with reduced vessels and glands. Although remodelling is generally considered to be consequence of persistent inflammation, the chronological order and relationship between inflammation and remodelling in polyp development is still not clear. The aim of our study was therefore to investigate the pathological features prevalent in the development of nasal polyps and to elucidate the chronological order and relationship between inflammation and remodelling, by comparing specific markers of inflammation and remodelling in early stage nasal polyps confined to the middle turbinate (refer to as middle turbinate CRSwNP) obtained from 5 CRSwNP patients with bilateral polyposis, mature ethmoidal polyps from 6 CRSwNP patients, and normal nasal mucosal tissue from 6 control subjects. Middle turbinate CRSwNP demonstrated significantly more severe epithelial loss compared to mature ethmoidal polyps and normal nasal mucosa. The epithelial cell junction molecules E-cadherin, ZO-1 and occludin were also expressed in significantly lower amounts in mature ethmoidal polyps compared to healthy mucosa. Middle turbinate CRSwNP were further characterized by significantly increased numbers of subepithelial eosinophils and M2 type macrophages, with a distinct lack of collagen and deposition of fibronectin in polyp part. In contrast, the turbinate area of the middle turbinate CRSwNP was characterized by an increase in TGF-β activated myofibroblasts expressing α-SMA and vimentin, an increase in the number of pSmad2 positive cells, as well as increased deposition of collagen. These findings suggest a complex network of processes in the formation of CRSwNP; including gross epithelial damage and repair reactions, eosinophil and macrophage cell infiltration, and tissue remodelling. Furthermore, remodelling appears to occur in parallel, rather than subsequent to inflammation.