R449 – The Role of DPZF in Inner Ear Development and Function

2008 ◽  
Vol 139 (2_suppl) ◽  
pp. P195-P195
Author(s):  
Gao Xia
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Inner Ear ◽  
Hair Cells ◽  
Otoacoustic Emissions ◽  
Auditory Brainstem ◽  
Auditory Brainstem Responses ◽  
Inner Ear Development ◽  
Scanning Electron

Problem The dendritic cell-derived BTB/POZ zinc finger (DPZF) protein belongs to the C2H2 zinc finger protein transcription factor family. It is localized on chromosome 3 and widely expressed in hematopoietic tissues, including human dendritic cells (DC), monocytes, B cells and T cells. DPZF null mice (DPZF-/-) exhibit a circling phenotype, suggestive of an inner ear defect. Here, we present our work on the role of DPZF in hearing defects. Methods We used auditory brainstem responses (ABR) and distortion production otoacoustic emissions (DPOAEs) to test the hearing function of DPZF-/- mice, then gross observation and histopathology analysis including serial sections and scanning electron microscopy were performed to exam the cochlea of DPZF-/- mice. Results Auditory brainstem responses (ABR) and distortion production otoacoustic emissions (DPOAEs) showed that DPZF-/-mice were completely deaf. Disorganized and fewer hair cells of the Corti organ in DPZF-/- mice were identified by scanning electron microscopy. Besides, although the hair cells of the utricle and saccule were grossly normal, the stereocilia were greatly reduced in number. Further more, lipofuscin was seen in the stria vascularis with the amount of which increased with age. Conclusion The impaired hearing and balance function and the morphological abnormalities of inner ears are caused by the deletion of DPZF gene. Significance DPZF gene may participates in regulating inner ear development and the DPZF null mice may serve as a new disease model of hearing loss. Support This work was supported by the ground of Jiangsu Province Famous Doctor Project(RC2007010).

R448 – Phex Mutation Causes Sensorineural Deafness in Mice

2008 ◽  
Vol 139 (2_suppl) ◽  
pp. P194-P195
Author(s):  
Gao Xia
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Hair Cells ◽  
Sensorineural Deafness ◽  
Organ Of Corti ◽  
Auditory Brainstem ◽  
Outer Hair Cells ◽  
Auditory Brainstem Responses ◽  
Phex Gene ◽  
Scanning Electron

Problem Pug is an ENU mutated mouse model for X-linked dominant hypophosphatemic rickets (XLH) in human. Mapping and sequence analysis revealed that Pug mutation is a unique Phe-to-Ser transition at amino acid 80 of PHEX protein leading to the loss of Phex function. Patients with XLH and Pug mutant mice exhibit abnormal phenotypes including growth retardation, hypophosphatemia and osteomalacia. In addition, hearing impairment was also found in some hypophosphatemic mouse models and patients. Here, we used the Pug mutant mice to study the role of Phex gene in the pathology of hearing impairment. Methods Auditory brainstem responses(ABR) to click and 8,16,32kHz stimuli were employed to measure pug mice of 1–8 months old. Serial sections were used to detect the abnormalities involving the temporal bone, stria vascularis, the organ of Corti, spiral ganglion cells, and scanning electron microscopy was performed to exam the basilar membrane of pug mice. Results Auditory brainstem responses test showed that Pug mice have elevated hearing thresholds. Histology analysis demonstrated a thickened temporal bone with many interspersed areas of nonmineralization surrounding the mutant cochlea and decreased numbers of neuronal processes in the organ of Corti, mostly in basal turns. Furthermore, abnormal stereocilia of inner and outer hair cells of the Corti organ were identified by scanning electron microscopy. Inner and outer hair cells were also greatly reduced in Pug mice. Conclusion The impaired hearing function and the morphological abnormalities of inner ears are induced by the mutation of Phex gene. Significance Pug mice have structural and functional defects in the inner ear and may serve as a new disease model of sensorineural deafness. Support This work was supported by the ground of JiangSu Province Femouse Doctor Project(RC2007010).

The use of scanning electron microscopy in interpreting chenopodium remains from three archaeological sites in northwestern Iowa

1992 ◽  
Vol 50 (2) ◽  
pp. 1112-1113
Author(s):  
Douglas William Jones
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Archaeological Sites ◽  
Late Prehistoric ◽  
Eastern United States ◽  
Chenopodium Berlandieri ◽  
Seed Identification ◽  
Level 2 ◽  
Scanning Electron

Within the past 20 years, archaeobotanical research in the Eastern United States has documented an early agricultural complex before the dominance of the Mesoamerican domesticates (corn, beans, and squash) in late prehistoric and historic agricultural systems. This early agricultural complex consisted of domesticated plants such as Iva annua var.macrocarpa (Sumpweed or Marshelder), Hellanthus annuus (Sunflower) and Chenopodium berlandieri, (Goosefoot or Lasbsquarters), and heavily utilized plants such as Polygonum erectum (Erect Knotweed), Phalaris caroliniana (May grass), and Hordeum pusillum (Little Barley).Recent research involving the use of Scanning Electron Microscopy (SEM) specifically on Chenopodium has established diagnostic traits of wild and domesticated species seeds. This is important because carbonized or uncarbonized seeds are the most commonly recovered Chenopodium material from archaeological sites. The diagnostic seed traits assist archaeobotanists in identification of Chenopodium remains and provide a basis for evaluation of Chenopodium utilization in a culture's subsistence patterns. With the aid of SEM, an analysis of Chenopodium remains from three Late Prehistoric sites in Northwest Iowa (Blood Run [Oneota culture], Brewster [Mill Creek culture], and Chan-Ya-Ta [Mill Creek culture]) has been conducted to: 1) attempt seed identification to a species level, 2) evaluate the traits of the seeds for classification as either wild or domesticated, and 3) evaluate the role of Chenopodium utilization in both the Oneota and Mill Creek cultures.

Effect of Zn on the intermetallics formation and reliability of Sn-3.5Ag solder on a Cu pad

2007 ◽  
Vol 22 (7) ◽  
pp. 1879-1887 ◽  
Author(s):  
Y.K. Jee ◽  
Y.H. Ko ◽  
Jin Yu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Isothermal Aging ◽  
X Ray Diffraction ◽  
X Ray ◽  
Drop Tests ◽  
Joint Microstructures ◽  
Role Of Zn ◽  
Scanning Electron

Varying amounts of Zn (1, 3, and 7 wt%) were added to Sn–3.5Ag solder on a Cu pad, and the resultant solder joint microstructures after a reflow and isothermal aging (150 °C, up to 500 h) were investigated using scanning electron microscopy, energy dispersive x-ray, and x-ray diffraction, which were subsequently correlated to the results of microhardness and drop tests. Zinc was effective in improving the drop resistance of Sn–3.5Ag solder on the Cu pad, and an addition of 3 wt% Zn nearly doubled the number of drops-to-failure (Nf). The beneficial role of Zn was ascribed to suppression of Cu6Sn5 and precipitation of Zn-containing intermetallic compounds (IMCs). However, the Zn effect was reduced as Cu6Sn5 and Ag3Sn precipitated in a joint IMC layer after prolonged aging. The interface between Ag5Zn8 and Cu5Zn8 was resistant to drop impact, but two other layered IMC structures of Cu6Sn5/Cu3Sn and Cu5Zn8/Cu6Sn5 were not.

scholarly journals Fine Structure of Maxillary Palps in Adults of Hermetia illucens (Diptera: Stratiomyidae)

2020 ◽  
Author(s):  
M Pezzi ◽  
C Scapoli ◽  
M Bharti ◽  
M J Faucheux ◽  
M Chicca ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Sexual Dimorphism ◽  
Hermetia Illucens ◽  
The Family ◽  
Sensory Structures ◽  
First Time ◽  
Maxillary Palps ◽  
Scanning Electron

Abstract A relevant species in waste management but also in forensic, medical, and veterinary sciences is the black soldier fly, Hermetia illucens (Linnaeus; Diptera: Stratiomyidae). An ultrastructural study by scanning electron microscopy (SEM) was conducted for the first time on maxillary palps of both sexes, describing in detail the morphology and distribution of sensilla and microtrichia. The maxillary palps, composed of two segments, show sexual dimorphism in length and shape. In both sexes, the first segment is covered only by microtrichia, but the second one is divided into two parts: the proximal one, covered only by microtrichia, and the distal one containing both microtrichia and sensory structures. These structures include two types of sensory pits and one of chaetic sensilla. Due to sexual dimorphism in palp size, females have a higher number of sensory pits. The sexual dimorphism of palps and the presence and role of sensilla in H. illucens was discussed in comparison to other species of the family Stratiomyidae and of other Diptera. This study may represent a base for further investigations on mouthpart structures of this species, involved in key physiological activities, such as feeding, mating and oviposition.

A novel method for assessing the role of iron and its functional chelation in fibrin fibril formation: the use of scanning electron microscopy

2013 ◽  
Vol 23 (5) ◽  
pp. 352-359 ◽  
Author(s):  
Etheresia Pretorius ◽  
Natasha Vermeulen ◽  
Janette Bester ◽  
Boguslaw Lipinski ◽  
Douglas B. Kell
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Fibril Formation ◽  
Novel Method ◽  
Scanning Electron
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