SGN nerve filaments develop synapses with IHCs earlier than with OHCs in C57BL/6 mouse inner ear

OBJECTIVE

To explore the connections between hair cells and spiral ganglion neurons (SGNs) during the development of the C57BL/6 mouse inner ear.

MATERIALS AND METHODS

The specimens of C57BL/6 mouse inner ear, from E15 (embryo day 15) to adult mouse, were collected; immunohistochemistry was employed to explore the frozen sections of specimens.

RESULTS

The development of cochlea starts sequentially from the basal turn to the apex turn. Morphological development of SGNs occurs mainly from E16 to P12 (postnatal day 12). Hair cells appear from E18 to P12, and inner hair cells (IHCs) develop earlier than outer hair cells (OHCs). The connections between hair cells and SGNs begin to develop during E18-P1, morphologically resemble mature synapses during P8-P12, and completely mature in adult mice.

CONCLUSIONS

The genesis of auditory ribbon synapse occurs from E18 to P1. Synchronized with the development of SGNs and hair cells, the functional filaments remain connected to hair cells, while the spare ones get disconnected from the surface of hair cells. Connections between SGN nerve filaments and IHCs occur earlier than those between SGN nerve filaments and OHCs.

Peroxiredoxin1 promotes cell proliferation, migration and invasion of colorectal cancer via p38MAPK signaling

OBJECTIVE

Peroxiredoxin1 (PRDX1), a class of thiol peroxidases, is a multifunctional protein. We aimed at analyzing the effect of PRDX1 on proliferation, apoptosis, migration and invasion of colorectal cancer and to investigate the potential mechanism.

MATERIALS AND METHODS

Western blot and PCR were used to validate the silencing efficiency in SW480 cell by transfection of PRDX1-siRNA. The cell proliferation was detected by Cell Counting Kit-8 (CCK-8) test. Flow cytometry Annexin V/PI double staining was used to analyze cell apoptosis. Transwell and scratch test were used to detect the migration and invasion of cells. Signal pathway protein expression was analyzed by Western blot.

RESULTS

The expression of PRDX1 in SW480 cells could be reduced by siRNA effectively. The cell proliferation, migration and invasion were reduced significantly compared with control group after down-regulation of PRDX1 (p<0.05), while the cell apoptosis was enhanced significantly (p<0.05). The ratio of phospho-p38 mitogen-activated protein kinases (p-p38) /p38 mitogen-activated protein kinases (p38) was down-regulated after the down-regulation of PRDX1 (p<0.05). The ratio of phospho-c-Jun N-terminal protein kinase (p-JNK)/c-Jun N-terminal protein kinase (JNK) and phospho-extracellular regulated protein kinases (p-ERK)/extracellular regulated protein kinases (ERK) showed changes with no significant difference (p>0.05).

CONCLUSIONS

Down-regulation of PRDX1 in colorectal cancer SW480 cells could inhibit the cell proliferation, migration, invasion, and induce cell apoptosis. This is very likely to be achieved by activating the p38MAPK-signaling pathway.

Allergic rhinitis and allergy are risk factors for otitis media with effusion: A meta-analysis

OBJECTIVE/HYPOTHESIS

We systematically reviewed the associations between allergic rhinitis or allergy and otitis media with effusion, by reference to published data.

STUDY DESIGN

A meta-analysis of case-controlled studies.

DATA SOURCE

Five databases (Pubmed, Highwire, Medline, Wanfang, and China National Knowledge Infrastructure) were searched for relevant studies in the English language published prior to November 12, 2015.

STUDIES CHOSEN

Studies with clearly defined experimental and control groups, in which the experimental groups had otitis media with effusion together with allergic rhinitis or allergy, were selected.

METHODS

We performed a meta-analysis on data from the identified cross-sectional and case-controlled studies using fixed- or random-effects models (depending on heterogeneity). We used Reviewer Manager 5.3 software to this end.

RESULTS

Seven studies met the inclusion criteria. The prevalence of allergic rhinitis in patients with otitis media with effusion and the control groups differed significantly in three studies (P<0.00001), as did the prevalence of allergy (in six studies; P=0.003).

CONCLUSION

Allergic rhinitis and allergy appear to be risk factors for otitis media with effusion.

Clinicopathological implications of tumour-associated macrophages and vascularization in sinonasal melanoma

This study investigated tumour-associated macrophages (TAMs) and their effects on tumour vascularization in sinonasal melanoma (SNM). Data on 45 patients with SNM undergoing surgery were reviewed retrospectively. Tumour sections were analysed immunohistochemically for TAMs, microvessels, lymph vessels, and vasculogenic mimicry in both intra- and peritumoural areas. The density of intratumoural TAMs was associated with tumour thickness and with overall survival in SNM stages I and II but there were no correlations between micro- or lymph vessel density and TAM infiltration. Greater TAM infiltration was observed in tumour tissues with vasculogenic mimicry although this was not statistically significant. These data suggest that high intratumoural TAM infiltration is associated with tumour aggressiveness and a poor prognosis for SNM, and that activation of macrophages can be polarized by different micro-environments. TAMs could be potential prognostic indicators for patients with SNM.

A comparative study of fatigue complaints among assembly line workers employed in the two electronic factories in Vietnam

A cross-sectional study concerning working conditions and the fatigue complaints of assembly line workers employed in two different electronic factories (A and B) in Vietnam was conducted from August to September 1994. While general working conditions, such as noise, dust, heat and lighting, were worse in Factory B, the prevalence rate of the subjective fatigue after working time was significantly higher among workers in Factory A. Fatigue symptoms in category I (Drowsiness and dullness) were particularly apparent among workers in Factory A. More interestingly, one-third of workers in Factory A complained of stiff shoulders and low back pain. Our field observation results suggest that the ergonomic inappropriateness of the assembly line in Factory A, may be causing a high rate of subjective fatigue among workers.