Confocal laser scanning microscopic analysis of ectopic sublingual gland‐like tissue inside the hamster submandibular gland

Based on its histochemical properties, the secretory portion of the hamster submandibular gland has been classified as seromucous cells. The presence of endogenous peroxidase (PO) reaction was shown in the nuclear envelope, cisternae of endoplasmic reticulum and Golgi apparatus. The 3,3′‐diaminobenzidene, tetrahydrochloride (DAB) method revealed bipartite secretory granules containing a PO‐positive dense core surrounded by a less dense halo in these cells. In the present investigation, serous and mucous‐like cells were found in resin‐embedded semi‐thin sections of the DAB‐reacted hamster submandibular gland. These sections were already on glass slides for routine light microscopic observations, therefore electron microscopic analysis could be unrealizable. We then used reflectance‐mode confocal laser scanning microscopy to visualize additional sites of PO activity as detected in these sections. Using this approach, we found mucous cells with PO activity‐negative secretory granules and seromucous cells with PO activity‐positive spot‐like secretory granules of the regular sublingual gland most frequently adjacent to the serous cells with typical electron‐dense secretory granules. These cells clearly differ from the seromucous cells with bipartite secretory granules and the granular duct cells with typical electron‐dense secretory granules of the hamster submandibular gland. Additionally, secretory endpieces of the ectopic sublingual gland‐like tissue empty into the duct of the hamster submandibular gland lobule. Thus, our findings suggest that a mass of sublingual gland tissue extends into the hamster submandibular gland during its development, and PO may be synthesized and secreted into the same duct. Microsc. Res. Tech. 76:1284–1291, 2013. © 2013 Wiley Periodicals, Inc.     

Mandibular gland components of european and africanized honey bee queens (Apis mellifera L.)

The composition of the five-component honey bee queen mandibular gland pheromone (QMP) of mated European honey bee queens was compared to those of virgin and drone-laying (i.e., laying only haploid unfertilized eggs that develop into males), European queens and Africanized mated queens. QMP of mated European queens showed significantly greater quantities of individual components than all queen types compared, except for a significantly greater quantity of 9-hydroxy-(E)-2-decenoic acid (9-HDA) found in Africanized queens. Glands of European drone-laying queens contained quantities intermediate between virgin and mated queens, reflecting their intermediate reproductive state and age. QMP ontogeny shifts from a high proportion of 9-keto-(E)-2-decenoic acid (ODA) in young unmated queens to roughly equal proportions of ODA and 9-HDA in mated queens. A biosynthetic shift occurs after mating that results in a greater proportion of 9-HDA, methylp-hydroxybenzoate (HOB), and 4-hydroxy-3-methoxyphenylethanol (HVA) production, accompanied by a decreased proportion of ODA. Africanized QMP proportions of ODA and 9-HDA were significantly different from European queens. A quantitative definition of a queen equivalent of QMP is proposed for the various queen types, and a standard queen equivalent for mated European honeybee queen mandibular gland pheromone is adopted as 200µg ODA, 80µg 9-HDA, 20µg HOB, and 2 µg HVA.     

3-Methyl-α-himachalene: Proposed structure for novel homosesquiterpene sex pheromone ofLutzomyia longipalpis (diptera: Psychodidae) from Jacobina,Brazil

The principal behaviorally active volatile component (ca. 90% +) of the sex pheromone glands ofLutzomyia longipalpis from Jacobina. Brazil, has been isolated and characterized as a novel homosesquiterpene with the structure 3-methyl--himachalene (C₁₆H₂₆). A minor component (ca. 10%) of the gland extract has also been identified as the sesquiterpene-himachalene (C₁₅H₂₄). This work confirms that there are at least 3 members of theL. longipalpis species complex.     

乳化液泵阀体下压盖锻压过程的数值模拟

采用DEFORM-3D软件对乳化液泵阀体下压盖锻压过程进行了三维有限元数值模拟,获得了有效塑性应力应变、载荷计算、材料流动及模具寿命预测分析,模拟结果为毛坯和模具设计优化提供了可靠的依据。     

黄河阿什贡电站砂土振动液化问题分析与处理

对阿什贡电站坝址区砂性土层存在的砂土振动液化问题进行分析,对泄水闸地基采用振冲碎石桩处理,对船闸地基采用高压旋喷桩处理,对左岸土石坝段进行回填压盖处理,并对压盖后的坝基砂性土层进行抗震复核计算,以论证该处理方案在理论上的可行性.     

Dufour's gland and its role in secretion of nest cell lining in bees of the genusColletes (Hymenoptera: Colletidae)

The liquid secretion of the Dufour's gland in mated females comprises a mixture of macrocyclic lactones, straight chain mono- and dicarboxylic acids, together with trace amounts of di- and trihydroxy monocarboxylic acids and a series ofn-alkanes. Polymerization of the liquid to form the membranous nest cell lining, which also contains alanine and glutamic acid as major constituents, may be mediated by an enzyme from the thoracic salivary gland and voided via the mouth. The composition and structure of the cell linings are similar to those of Wigglesworth's cuticulin.     

A review of rapid microwave fixation technology: Its expanding niche in morphologic studies

Microwave (MW) fixation methods are important because excellent preservation of both cell structure and antigenicity can be attained several orders of magnitude faster than by routine chemical fixation methods. However, because of the limitations of commercial MW ovens, fixation results are often irreproducible. We present a standardization protocol for MW fixation in household MW ovens that emphasizes magnetron warm-up; the use of a water load during sample irradiation, of an agar/saline/Giemsa model to evaluate uniformity of irradiation within the MW cavity, and of specimen containers with one dimension less than 1.5 cm; and fast specimen handling to prevent conductive heating artifacts after irradiation. We describe a prototypic MW device that improves the precision of sample irradiation and fixes blocks of tissue and cells in suspension in milliseconds. The solutions used to immerse the specimen during irradiation influence the specimen morphology. Aldehyde- or osmium-containing solutions used simultaneously with MW irradiation resulted in the best morphologic preservation of specimens up to 1 cm³. Using MW fixation methods and a postembedding, ultrastructural immunogold-labeling approach, we have localized granule chymase and histamine in rat mast cells and amylase in rat parotid acinar cells.     

Behavioral and Olfactory Responses of Female <Emphasis Type="Italic">Salaria pavo</Emphasis> (Pisces: Blenniidae) to a Putative Multi-component Male Pheromone

The peacock blenny, Salaria pavo (Risso 1810), typically breeds in rocky shores of the Mediterranean and adjacent Atlantic coast. Males defend a territory around a hole or cavity wherein females deposit eggs that the male guards until hatching. A pair of exocrine glands on the anal fin (anal glands) of males produces a putative pheromone involved in attraction of reproductively competent females to the nest. We used behavioral assays to assess species-specific attraction of reproductively competent females to putative male pheromones, including the anal gland pheromone. Additionally, chromatographic fractions of anal glands and male-conditioned water were tested for olfactory potency in females by electro-olfactogram analysis (EOG). In a flow-through tank or fluviarium, reproductive females were attracted to male-conditioned water and to the anal gland macerate from conspecifics but not to those of a closely related heterospecific. In addition, attraction of reproductive females to conspecific anal gland macerate occurred only during their initial upstream movement in the fluviarium; this was an ephemeral response when compared with the response to male-conditioned water that attracted females throughout the entire period of observation (5 min). Reproductive females also were attracted during the entire period of observation to water-conditioned by conspecific males whose anal glands had been removed. However, the attraction was more variable than that to water conditioned by intact males. Moreover, females were not attracted to male (without anal glands) odor during their initial upstream movement in the fluviarium. Finally, non-reproductive females were not attracted to the conspecific anal gland macerate. The EOG responses of females to molecular weight fractions and solid-phase extraction and high-performance liquid chromatography fractions of anal gland macerates and male-conditioned water (with and without anal glands) suggest that the anal glands release hydrophilic odorants that consist mainly of molecules smaller than 500 Da. Furthermore, males released potent odorants that do not originate from the anal glands. We hypothesize that females respond to a multi-component male pheromone to find mates. The putative anal gland pheromone is possibly comprised of hydrophilic odorants, whereas the other component(s), presumably of gonadal origin, may be less water-soluble. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Proteases involved in mammary tissue damage during endotoxin-induced mastitis in dairy cows

During and after diapedesis, milk polymorphonu-clear neutrophils (PMN) release many proteases that have the potential of degrading extracellular matrix proteins and milk proteins. However, the kinetics of milk proteolysis during inflammation and the underlying mechanisms are poorly defined. The enzymes involved in bovine mammary tissue destruction were investigated in this study using an endotoxin-induced mastitis model. Using zymography techniques, the proteolytic activity of milk and mammary tissue during mastitis was examined. Mastitic milk produced 6 caseolysis bands, 4 of which differed from the ones produced by plasmin. Peak proteolytic activity, bovine serum albumin contents, and mammary tissue damage occurred between 6 and 12 h postchallenge. Mastitic milk proteases hydrolyzed casein, gelatin, collagen, hemoglobin, mammary gland membrane proteins, and lactoferrin. These results confirm that mastitic milk proteases have a broad spectrum of activity. The hydrolytic activity of mastitic milk was partially inhibited by aprotinin, EDTA, 1,10-phenanthroline, leupeptin, and pefabloc. When cocultured with normal mammary tissue, mastitic milk, but not normal milk, caused mammary tissue degradation. In situ zymography of mammary gland showed increased proteolytic activity in mastitic tissue compared with normal tissue. The similarity of zymograms of mastitic milk, blood PMN, milk somatic cells, and PMN strongly suggests that proteases in mastitic milk mainly originate from milk PMN. These results suggest that proteases released by PMN are actively involved in udder tissue damage during mastitis.     

Imaging meibomian glands on a patient with chalazia in the upper and lower lids: A case report

AimTo describe the meibomian gland (MG) appearance in a case of eyelid chalazia, using a novel meibography method.MethodsA 29-year-old female of South Asian origin presented with mild swelling in the lower lid of the left eye. The patient also presented with a history of a recurrent chalazion in the upper lid of the same eye, which later progressed to an active chalazion. A chalazion also developed in the upper lid of the right eye. Meibography was performed using a novel Keratograph (Keratograph 4, OCULUS, Wetzlar, Germany) to evaluate the structure of the MG in the area affected by the chalazia.ResultsThe area of the recurrent chalazion in the upper left lid showed partial and/or complete MG loss. The active chalazia in the lower left lid and the upper right lid showed inflammation and MG drop out at the affected site. The inflammation was found to be reduced during the follow-up visits, however disappearance of MG very specific to the region of the chalazion was observed.ConclusionThe Keratograph 4 was able to image the MG structures clearly, allowing the clinician to monitor the progression of chalazia and the MG loss in the affected areas.