The comparative anatomy of the pig middle ear cavity: a model for middle ear inflammation in the human?

This study was undertaken to develop a functional model of otitis media with effusion (OME) in the pig ( Sus scrofa ), with the purpose of investigating the origin of lymphocytes populating the middle ear during the course of an inflammatory process. The relevance of the model to the human condition of OME is to a large extent dependent on the anatomical and physiological similarities between the middle ear cavity and the pharyngeal lymphoid tissue of the pig and man. Anatomical specimens were collected from 7 young Large White pigs to determine the gross anatomy of the middle ear cavity and the histological characteristics of the middle ear mucosa. It was found that the anatomy of the 3 parts of the middle ear cavity in man and in the pig is broadly similar, although some minor differences were observed. The porcine eustachian tube was seen to be cartilaginous throughout its length in contrast to the part osseous, part cartilaginous structure found in man; the porcine ossicles were slightly different in shape to those of man and the air cell system was situated inferior to the tympanic cavity in the pig as opposed to posteriorly in man. This paper describes the structure and morphology of the pig middle ear cavity and compares and contrasts it with that of man. The minor differences observed are of anatomical importance but do not diminish the usefulness of the pig middle ear cleft as a potential model for human middle ear disorders.     

耳内镜下人工镫骨手术在耳硬化症治疗中的应用价值

目的:探讨耳内镜下人工蹬骨手术在耳硬化症治疗中的临床应用价值。方法:回顾性分析2017年12月—2019年12月安徽医科大学第一附属医院耳鼻咽喉头颈外科22例耳硬化症患者的临床资料,其中男9例、女13例,年龄13～70(33.4±11.2)岁。患者均在耳内镜下行人工镫骨手术。术后观察患者眩晕、面瘫及味觉障碍等术后并发症...     

Pattern of bacterial isolates in the middle ear discharge of patients with chronic suppurative otitis media in a tertiary hospital in North central Nigeria

Background

Otitis media (OM) is a major health problem in both developed and developing countries.

Objective

To determine the pattern of bacterial isolates in patients with chronic suppurative otitis media(CSOM) in Ilorin, Nigeria.

Methods

A prospective study carried out in University of Ilorin Teaching Hospital, Nigeria among consenting patients with CSOM attending the ENT clinic over a period of 7months. Informed consent was obtained from the patients or caregivers and approval for the study obtained from ethical committee. Structured questionnaire was administered and microbiological analysis done, data obtained was entered into SPSS statistical software and results presented in tables and figures.

Results

A total of 134 patients aged 5–64yrs with chronic suppurative otitis media were interviewed with a mean age of 17.0 (S.D. =15.1±1.30). About 55.2% of the respondents were under 10yrs. Seventy-two (53.7%) of the respondents were males with M:F=1.2:1. The gram stain showed predominantly gram negative organisms (71.6%). Pseudomonas aeruginosa was the commonest middle ear pathogenic organism identified and the sensitivity pattern highly favoured ciprofloxacin

Conclusion

CSOM is still a childhood problem among the under tens'' more prevalent among males and the commonest agent is Pseudomonas aeruginosa. Ciprofloxacin is still the most sensitive antibiotics in vitro.     

Morphometric study of the external and middle ear anatomy in sheep: a possible model for ear experiments

Sheep are a potentially useful model for otologic surgical training and experimentation, currently limited by the scarcity of morphological comparisons between the structure of the ear in sheep and in humans. A detailed morphometric study of the ear in sheep was carried out using computed tomography. Measurements made with AutoCAD Release 14 were compared with measurements for the human ear reported in the literature. In general, ear structures in sheep are two-thirds the size of those in humans. The important anatomical similarities found in this study between the ear in sheep and in humans suggest that sheep may be a useful model for surgical training and experimentation in some middle ear procedures.     

Morphogenesis of the middle ear ossicles and spatial relationships with the external and inner ears during the embryonic period

We describe the three‐dimensional morphogenesis of the middle ear ossicles (MEOs) according to Carnegie stage (CS) in human embryos. Seventeen samples including 33 MEOs from CS18 to 23 were selected from the Kyoto Collection. The primordia of the MEOs and related structures were histologically observed and three‐dimensionally reconstructed from digital images. The timing of chondrogenesis was variable among structures. The stapes was recognizable as a vague condensation of the mesenchymal cells in all samples from CS18, whereas the malleus and incus were recognizable at CS19. Chondrogenesis of all MEOs was evident in all samples after CS21. The chondrocranium was recognizable in all samples by CS18, and the perichondrium border of the auricular cartilage and otic capsule was distinct in all samples at CS23. At CS19, the MEOs were positioned in the anterior to posterior direction, following the order malleus, incus, stapes, which adjusted gradually during development. The MEOs connected in all samples after CS22. The stapes was located close to the vestibular part of the inner ear, although the basal part was not differentiated into the “footplate” form, even at CS23. The handles of the malleus were close to the tubotympanic recess at CS23, but were distant from the external auditory meatus. Determining the timeline of the formation of MEOs and connection of the external and inner ears can be informative for understanding hearing loss caused by failure of this connection. These data may provide a useful standard for morphogenesis, and will contribute to distinguishing between normal and abnormal MEO development. Anat Rec, 299:1325–1337, 2016. © 2016 Wiley Periodicals, Inc.     

Interaction of pneumococcal phase variation and middle ear pressure/gas composition: an in vitro model of simulated otitis media

Streptococcus pneumoniae, a leading cause of otitis media (OM), undergoes spontaneous intra-strain variations in colony morphology. Transparent (T) variant is more efficient in colonizing the nasopharynx while the opaque (O) variant exhibits greater virulence during systemic infections. We hypothesized that changes in middle ear (ME) gas pressure/composition during Eustachian tube (ET) dysfunction and the treatment of that dysfunction, e.g., tympanostomy tube (TT) insertion, play a role in selecting the S. pneumoniae variant that can efficiently colonize/infect the ME mucosa. Human ME epithelial cells were preconditioned for 24h under one of three conditions that simulated (1) normal ME, (2) ME with ET obstruction (ETO) and (3) ME with TT; subsequently exposed to a dose (approximately 10(7)CFU/ml) of either T or O variant of S. pneumoniae, and then incubated for 1h and 3h. Under the simulated ETO and TT conditions, T variant exhibited a higher growth rate and greater epithelial adherence and killing than did O variants. Attachment of T variant to epithelial cells was documented by scanning electron microscopy. These results suggest that the T variant is more highly adapted to various ME environments than the O variants.     

Eosinophil chemoattractants in the middle ear of patients with eosinophilic otitis media

BACKGROUND: Patients with intractable otitis media associated with bronchial asthma have an extensive accumulation of eosinophils in the effusion and mucosa of the middle ear; this condition is called eosinophilic otitis media (EOM). It remained to be determined how eosinophils accumulate in the middle ear. OBJECTIVES: To clarify the pathogenesis of middle ear diseases, we measured the concentration of eosinophil chemoattractants in middle ear effusion (MEE), and carried out immunohistochemical studies of middle ear mucosa specimens to demonstrate the expression of eosinophil chemoattractants. METHODS: Middle ear effusion samples were obtained from 15 EOM patients with bronchial asthma and from six controls for the measurement of eosinophil cationic protein (ECP), IL-5, eotaxin and regulated on activation, normal T expressed and secreted concentrations. Middle ear mucosa samples were also taken from 14 EOM patients and 16 controls for immunohistochemical study. In 10 EOM patients, the numbers of immunoreactive cells as well as apoptotic cells were determined before and after the topical application of triamcinolone acetonide into the middle ear. RESULTS: In EOM, significantly higher ECP and IL-5 concentrations were detected in MEE than in serum, and ECP, IL-5 and eotaxin concentrations in MEE were higher in the EOM patients than in the controls. ECP concentration positively correlated with that of IL-5. Immunohistochemically, the numbers of cells positive for EG2 and ecalectin were significantly higher in the EOM patients than in the controls. After the topical application of triamcinolone acetonide, the numbers of infiltrating cells and immunoreactive cells distinctly decreased, whereas the number of apoptotic cells significantly increased. CONCLUSION: In EOM, locally produced IL-5 may play a crucial role in the accumulation of eosinophils in the middle ear. Chemokines such as ecalectin and eotaxin are also produced in the middle ear, and help activate and enhance the survival of eosinophils to induce the intractable condition in the middle ear. The topical application of triamcinolone acetonide induces the apoptosis of not only eosinophils but also eosinophil chemoattractant-producing cells, thereby improving the middle ear condition.     

Complement activation and expression of membrane regulators in the middle ear mucosa in otitis media with effusion.

The aetiopathogenesis of chronic otitis media with effusion (OME) in children is not yet fully understood. OME is characterized by metaplasia of the epithelium and accumulation of sticky, glue-like effusion in the middle ear containing different mediators of inflammation, including activation fragments of the complement system. Here we examined whether the fluid phase complement activation is reflected in the middle ear mucosa and how the mucosa is protected against the cytolytic activity of complement. Mucosal biopsies from 18 middle ears of children with a history of chronic OME were taken. The biopsies were analysed by immunofluorescence microscopy after staining for complement fragments iC3b/C3c, C3d and C9, and regulators membrane cofactor protein (MCP; CD46), decay-accelerating factor (DAF; CD55) and protectin (CD59). There was a strong staining for iC3b/C3c, and a weaker one for C3d and C9 on the surface of the middle ear epithelial cells of OME patients but not in controls without OME. MCP was expressed on the hyperplastic three to four outer cell layers of the epithelium, while CD59 was expressed throughout the middle ear mucosa. The results suggest a strong ongoing complement activation and consequent inflammation in the middle ear cavity. Unrestricted complement damage of the epithelial lining is prevented by the strong expression of MCP and CD59.     

Immunological Status in the Aetiology of Recurrent Otitis Media with Effusion: Serum Immunoglobulin Levels,Functional Mannose-Binding Lectin and Fc Receptor Polymorphisms for IgG

The objective was to study the role of serum immunoglobulin levels, mannose-binding lectin (MBL), and Fc gamma receptor (FcR) polymorphisms on the development of recurrent otitis media with effusion (OME). Children aged between two and seven years with persisting OME received bilateral tympanostomy tubes and immunological parameters were investigated in relation with OME recurrence within six months after tube extrusion. No statistically significant differences in serum immunoglobulin levels were present between children with and without OME recurrence. In children with bilateral recurrence (n = 56), median levels of MBL were 1.39 mg/L compared to 2.48 mg/L in children with OME recurrence (n = 17) (p = 0.29). In addition, 34% of the children with bilateral recurrence were homozygous for the genotype FcRIIa-R/R131, whereas less than 20% of the children with unilateral recurrence or those without recurrence were homozygous for this Fc receptor (p = 0.26). Serum mannose-binding lectin and FcRIIa-R/R131 polymorphism may play a role in the aetio-pathogenesis of recurrent OME.     

Arthroscopic fixation for tibial eminence fractures: A clinical retrospective study of cannulated screws versus transosseous anchor knot fixation techniques with suture anchors

BackgroundA variety of different techniques or methods for treatment of tibial eminence fracture (TEF) have been reported, but there is still controversy on the optimum choice for treating TEFs. The aim of the current work was to compare the clinical outcomes of arthroscopic cannulated screw fixation and a new arthroscopic anchor fixation technique for tibial eminence fracture.MethodsWe included 69 isolated tibial eminence fracture patients from June 2012 to February 2017; 36 patients received the cannulated screw fixation and 33 received the transosseous anchor knot (TAK) fixation under arthroscopy. The two techniques were performed by two different high-volume surgeons. The clinical efficacies of the two techniques were assessed by radiographs, extension deficit, flexion deficit, anterior drawer test (ADT), Lachman test, Lysholm scores and International Knee Documentation Committee (IKDC) scores in follow ups.ResultsPatients were followed up for 35.8 months on average (range, 24–54 months). There were 40 (58%) males and 29 (42%) females included, and four (6%) patients were ＜18 years old. Asymptomatic grade II laxity was found in two patients in the CS group and three patients in the TAK group from the results of Lachman test. Postoperative radiographs in all patients showed anatomic reductions and bony unions were achieved within 12 weeks. There were no significant differences in extension deficit, flexion deficit, ADT, Lachman test, Lysholm scores and IKDC scores between groups (P > 0.05).ConclusionsThe TAK technique shows satisfactory clinical and radiological outcomes equal to the cannulated screw fixation, which is applicable for TEFs as a reliable effective method.     

A novel method for the serum-free plating of stage-24 chick limb bud cells

Summary A modification of the standard plating of Stage 24 chick limb bud cells in serum-containing media (SCM) is described in which the cells are incubated in SCM for 3 hours before direct plating in a serum-free chemically defined media (SFM). This results in equal plating efficiencies to those obtained with plating in SCM and may allow for more defined culture conditions when testing mitogenic growth factors found in serum.     

Effect of central depressants on the acoustic middle ear reflex in rabbit. A method for quantitative measurements of drug effect on the CNS.

The respective effects of pentobarbital-sodium, enibumal-sodium, urethane, urethane-chloralose and lidocaine on the function of the acoustic middle ear reflex in the rabbit were studied. The response of the middle ear muscles was measured by recording changes in both ears' acoustic impedance when the reflex was elicited by applying pure tone stimuli (2,000 Hz) to the two ears one at a time. In that way both the crossed and the uncrossed reflexes were studied. All the drugs were found to depress the reflex in such a way that a higher sound intensity was required after administration to achieve the same impedance change as before. The effect of the anesthetics was roughly proportional to their known anesthetic power. Lidocaine produced only a slight depression of the reflex. The crossed reflex showed a greater susceptibility to the general anesthetics than did the uncrossed reflex which suggests a greater complexity of the crossed reflex. Because the method of recording the reflex response does not require any surgery and is equally well applicable in unrestrained rabbits and in humans, it is suggested as a way of testing the effect of drugs on the central nervous system.     

A simulation method for the study of laser transillumination of biological tissues

The Monte-Carlo method is employed to simulate the illumination of a blood slab by a continuous laser. It is assumed that the geometry of the medium is bidimensional and that scattering or absorption takes place only when a photon strikes a red blood cell. The parameters involved in the calculations concern the photons free path lengths between two collisions, the scattering angles and the absorption probability at collision. These parameters are assessed according to experimental or literature data. Fortran programs allow the computation of diffuse and collimated transmittances (T_d and T_c, respectively), of transmittance measured with an optic fiber T_f and of reflectance R. The variations of T_c and T_f with blood thickness are in accordance with established laws. Moreover, measured and computed reflectances change with hematocrit ratio in a similar way. This work demonstrates that the Monte-Carlo method is a simple reliable tool which can be used to provide a realistic model of laser penetration in complex biological structures. Moreover, this method will permit investigations in laser tomospectrometry by providing a useful simulation of the interaction of ultrashort light pulses with biological media.     

Dark-field focus assay: An improved method for the quantification of transforming retroviruses

Dark-field optics were used for the counting of foci in cultures infected with transforming retroviruses. This method greatly increases counting efficiency and reduces operator fatigue.     

A method for carpal motion hysteresis quantification in 4-dimensional imaging of the wrist

IntroductionCarpal bones motions exhibit hysteresis that is dependent on the direction of wrist motion, which can be seen during 4-dimensional (3D plus time) imaging of the wrist. In vitro studies have demonstrated the phenomenon of carpal hysteresis and have reported that hysteresis area increases with carpal instabilities. However, their techniques required implantation of bone markers and thus cannot be used clinically. The objective of this study is to use noninvasive 4-dimensional computed tomography (4DCT) technique to quantify carpal hysteresis, and to determine the reliability of this method.MethodA cadaveric wrist mounted on a custom motion simulator was imaged using a dual-source CT scanner while undergoing periodic radioulnar deviation. Ten image phases of this motion was reconstructed through retrospective cardiac gating. The rotational angles of scaphoid, lunate and triquetrum in each phase were derived through manual registration using Matlab after segmenting the bones in Analyze 8.1. These angles were then plotted against global wrist positional angles to produce the hysteresis curves and the area was calculated. The image segmentation and measurements were repeated by 2 raters to derive intra- and inter-rater reliability assessments.ResultsThe hysteresis area was found to be larger in the lunate (96.5 deg²) followed by triquetrum (92.3 deg²) and scaphoid (67.5 deg²). The measurement of the total hysteresis area of the scaphoid had the highest reliability with intra- and inter-rater reliability of 95.5% and 95.4% respectively.DiscussionWe have demonstrated that our approach of using 4DCT imaging can be used to assess and quantify the hysteresis of the carpal motion with good reliability.     

A new statistical method for quantitative analyses: application to the precise quantification of T cell receptor repertoires

In experimental immunology, a situation quite commonly arises in which there are a large number of potential events but the probability of any individual event is small and one wishes to measure the number of events which actually occur. We present a new general statistical method, denoted Continuous Poisson Method (COPOM), for estimating the number of events underlying a quantitative measurement. This situation is well illustrated in the case of quantitative analyses of the immune receptor repertoire in a diverse population of cells. We show that repetition of T cell receptors (TCRs) complementarity determining region 3 (CDR3) length measurements by Immunoscope, on independent samples containing the similar numbers of cells prepared from splenocytes, results in variable profiles. When analyzed by COPOM, this variability provides direct quantification of the lymphocytes expressing any antigen receptor with a given V, J and CDR3 length inside the cell population. Using COPOM, a single dilution was sufficient to cover events over a 100-fold variation in frequency and the sensitivity of the assay was such that a single cell inside a pool of 5 x 10(4) lymphocytes could be quantified. A comparison of the frequency of splenocytes using either Vbeta14-Jbeta or the specific Vbeta8.3-Jbeta1.1 rearrangement, determined either by our or other approaches, revealed the accuracy and convenience of our method. This approach provides the first precise method able to measure the diversity of the antigen receptor repertoire inside a complex cell population by the use of a single straightforward technique.     

Adenoids provide a microenvironment for the generation of CD4(+), CD45RO(+), L-selectin(-), CXCR4(+), CCR5(+) T lymphocytes, a lymphocyte phenotype found in the middle ear effusion

Adenoidectomy in children with otitis media with effusion reduces inflammation in the middle ear by an unknown mechanism. Potentially, the adenoids of these children may serve as a site for the differentiation of lymphocytes, which after entering blood circulation eventually extravasate in the middle ear mucosa and thereby contribute to excessive inflammation. During lymphocyte extravasation various adhesion molecules and chemokines play a crucial role. To evaluate possible connections between the adenoids and middle ear inflammation, the expression of the chemokine receptors CXCR4 and CCR5 and the lymphocyte homing receptor L-selectin were analyzed in adenoidal and middle ear lymphocytes. It was found that most CD4(+) T lymphocytes in the middle ear effusion express the memory phenotype marker CD45RO and the chemokine receptors CXCR4 and CCR5, but are negative for the lymphocyte homing receptor L-selectin. This cell phenotype was rare in peripheral blood but was found much more frequently in the adenoids. The results suggest that the adenoids provide a microenvironment for the generation for CD4(+), CD45RO(+), L-selectin(-), CXCR4(+) and CCR5(+) T lymphocytes. Further, these cells may include cells that have the capacity to home to the middle ear mucosa. As the adenoidal CD4(+) memory phenotype CD45RO(+) T cells expressed the activation antigen CD69 and included cells expressing the HIV co-receptors CXCR4 and CCR5 at a high level, they may be permissive for HIV infection.