Transcription of cytochrome P450 46A1 in NIH3T3 cells is negatively regulated by FBS.

Extracellular administration of side-chain oxysterols, such as 24S-hydroxycholesterol (24S-HC), 27-hydroxycholesterol (27-HC) and 25-hydroxycholesterol (25-HC) to cells suppresses HMG-CoA reductase (Hmgcr) and CTP:phosphoethanolamine cytidylyltransferase (Pcyt2) mRNA levels. Oxysterols are enzymatically produced in cells from cholesterol by cytochrome P450 46A1 (Cyp46A1), Cyp27A1, Cyp3A11 and cholesterol 25-hydroxylase (Ch25h). We analyzed which of these oxysterol-producing enzymes are expressed in NIH3T3 cells and found that only Cyp46A1 was expressed. When Cyp46A1 was overexpressed in NIH3T3 cells, intrinsic oxysterols increased in the order 24S-HC > 25-HC > 27-HC. We investigated the mechanism regulating the production of endogenous oxysterols in NIH3T3 cells by Cyp46A1 and found that the mRNA, relative protein levels and enzymatic activity of Cyp46A1, and the amounts of 24S-HC, 25-HC and 27-HC significantly increased under serum-starved conditions, and these increases were suppressed by FBS supplementation. The aqueous phase of FBS obtained by the Bligh & Dyer method significantly suppressed Cyp46A1 mRNA levels. Fractionation of the aqueous phase by HPLC and analysis of the inhibiting fractions by nanoLC and TripleTOF MS/MS identified insulin-like factor-II (IGF-II). Cyp46A1 mRNA levels in serum-starved NIH3T3 cells were significantly suppressed by the addition of IGFs and insulin and endogenous oxysterol levels were decreased. CYP46A1 mRNA levels in the T98G human glioblastoma cell line were also increased by serum starvation but not by FBS supplementation, and the aqueous phase did not inhibit the increase. These results suggest that mRNA levels of Cyp46A1 are regulated by factors in FBS.

Molecular subtyping for source tracking of Escherichia coli using core genome multilocus sequence typing at a food manufacturing plant.

When harmful bacteria are detected in the final product at a food manufacturing plant, it is necessary to identify and eliminate the source of contamination so that it does not occur again. In the current study, the source of contamination was tracked using core genome multilocus sequence typing (cgMLST) analysis in cases where Escherichia coli was detected in the final product at a food manufacturing plant. cgMLST analysis was performed on 40 strains of E. coli collected from the environment [floor (26 strains), drainage ditch (5 strains), container (4 strains), post-heating production line (1 strain)] and products [final product (3 strains) and intermediate product (1 strain)]. In total, 40 E. coli isolates were classified into 17 genogroups by cgMLST analysis. The 4 E. coli strains isolated from the intermediate and final products were classified into two genogroups (I and II). Certain isolates collected from the environment also belonged to those genogroups, it was possible to estimate the transmission of E. coli in the manufacturing plant. Thus, the dynamics of E. coli in the food manufacturing location were clarified by using cgMLST analysis. In conclusion, our results indicate that cgMLST analysis can be effectively used for hygiene management at food manufacturing locations.

Postoperative Course of Pars Flaccida Cholesteatoma Patients With Habitual Sniffing.

OBJECTIVE: To investigate the effects of habitual sniffing on the postoperative course of pars flaccida cholesteatoma. STUDY DESIGN: Retrospective case series study. SETTING: University hospital. PATIENTS: Forty-nine patients (53 ears) with pars flaccida cholesteatoma and history of habitual sniffing before the initial operation. INTERVENTIONS: Patients were divided into a "sniffing cessation group" characterized by sniffing cessation and a "continual sniffing group" characterized by continuation of sniffing despite instructions for conscious cessation. MAIN OUTCOME MEASURES: Hearing level, tympanic membrane findings, tympanograms, mastoid cell development before the operation, and pneumatization 1 year postoperatively. RESULTS: The sniffing cessation and continual sniffing groups comprised 35 patients (38 ears) and 14 patients (15 ears), respectively. The average postoperative hearing was slightly better in the continual sniffing group. In the sniffing cessation group, retractions were evident in significantly fewer cases. Retractions were observed in all continual sniffing group cases, with a high percentage of severe retractions, wherein the bottom was not visible. Type A tympanogram was predominant in the sniffing cessation group. Mastoid cell development was not significantly different between the two groups. Satisfactory pneumatization was significantly more common in the sniffing cessation group (Fisher's exact test, p < 0.005). CONCLUSION: Conscious cessation of the sniffing habit could reduce the risk of postoperative retraction and improve pneumatization in patients with pars flaccida cholesteatoma. The presence or absence of the sniffing habit after surgery is a defining factor in postoperative prognosis (retraction, recurrence), and may be a determinant for decisions regarding surgical approach.

Efficacy of a silicone plug for patulous eustachian tube: A prospective, multicenter case series.

OBJECTIVES/HYPOTHESIS: To report the efficacy and safety of transtympanic plugging of the eustachian tube (ET) using a silicone plug (Kobayashi plug) for chronic patulous ET (PET). STUDY DESIGN: Prospective and multicenter trial conducted in which 30 PET patients were resistant to at least 6 months of conservative treatment. METHODS: The efficacy and safety of 28 and 27 patients, respectively, were analyzed. All patients fulfilled inclusion and exclusion criteria. The primary end point used the patulous eustachian tube handicap inventory-10 (PHI-10), and the secondary end point used ET function tests such as sonotubometry, tubo-tympano-aerodynamic-graphy, and respiratory movement of the tympanic membrane and auscultation of voice sounds transmitted from the nose through the ET to the external auditory canal at 3months after surgery. RESULTS: PHI-10 scores were 34.4 ± 4.2, 6.4 ± 9, and 5.7 ± 8.6 at screening, and 3 and 6 months after surgery. Twenty-three cases (82.1%, 95% confidence interval: 63.1%-93.9%) were judged as successes. There were five cases (17.2%) of middle ear effusion, four cases (13.8%) of tympanic membrane perforation, and one case of tinnitus due to surgery to remove the plug. No severe or life-threatening complications were found. CONCLUSIONS: This study revealed the efficacy and safety of silicone plug insertion for severe PET patients. LEVEL OF EVIDENCE: 2 Laryngoscope, 130:1304-1309, 2020.

Characterization of glycerophosphodiesterase 4-interacting molecules Gαq/11 and Gß, which mediate cellular lysophospholipase D activity.

We previously purified lysophospholipase D (lysoPLD), which hydrolyzes lysophosphatidylcholine (lysoPC) to lysophosphatidic acid (LPA), from rat brain and identified the heterotrimeric G protein subunits Gαq and Gß1 in the lysoPLD active fractions. Tag-affinity purified Gαq exhibits lysoPLD activity but a mutant that affected cellular localization or interaction with the Gß subunit reduced lysoPLD activity. Size exclusion chromatography revealed that active lysoPLD is a much higher molecular mass complex than is heterotrimeric G protein, suggesting the presence of other components. Liquid chromatography-tandem mass spectrometry of lysoPLD purified from rat brain identified glycerophosphodiesterase 4 (GDE4), recently reported as lysoPLD, in the same fraction as G proteins. The overexpressed and tag-purified Gαq fractions, which exhibit lysoPLD activity, contained GDE4. Exogenously expressed GDE4 was co-immunoprecipitated with endogenous Gαq and Gß and exhibited high lysoPLD activity. The results of confocal microscopy and cell fractionation experiments indicated that exogenously expressed GDE4 in cells mainly localized at the endoplasmic reticulum and partially co-localized with Gαq protein at the plasma membrane. Proteinase K protection assay results suggested that the catalytic domain of GDE4 faces the lumen/extracellular space. Mutations at the conserved amino acids in the C-terminus cytoplasmic regions amongst GDE1, 4 and 7, dramatically suppressed GDE4 enzyme activities. When both the Gαq and Gα11 genes in Neuro2A cells were disrupted using the CRISPR-Cas9 system, endogenous lysoPLD activity was partially reduced but rescued by overexpression of Gαq. These results suggest that GDE4 is a new effector of G protein signaling that produces bioactive phospholipid LPA and/or modulates membrane homeostasis.

Ultrastructural localization of cochlin in the rat cochlear duct.

Cochlin, a product of the COCH gene, is a major constituent of the inner ear extracellular matrix. Type II collagen, a protein that contributes to structural stability, is also a component of this extracellular matrix. In this study, using the postembedding immunogold method, we demonstrate the localization of cochlin and type II collagen in the cochlear duct at the ultrastructural level. The immunolabeling of cochlin was observed in the fibrillar substance in the spiral limbus, beneath the inner sulcus cells, and in the basilar membrane, the spiral prominence and the spiral ligament. Immunolabeling of type II collagen was observed in the same fibrillar substance in the extracellular matrix of the cochlear duct. This localization of cochlin is consistent with the expected localization of type II collagen. The localization of cochlin and type II collagen indicates the important roles played by these proteins in the hearing process.

Localization of megalin in rat vestibular dark cells and endolymphatic sac epithelial cells.

CONCLUSION: Megalin immunoreactivity was observed in kidney proximal tubule cells, vestibular dark cells, and epithelial cells of the endolymphatic sac. Endocytic mechanisms appear to differ between the endolymphatic sac and proximal tubule cells. We speculate that megalin is secreted by a certain type of cell into the endolymphatic space, and is then absorbed from the endolymphatic space by another type of cell to maintain endolymphatic sac homeostasis. OBJECTIVES: We previously detected megalin immunoreactivity in the rat cochlear duct. Megalin may be involved in endocytosis in the vestibular organ and endolymphatic sac. To examine this possibility, we extended our immunocytochemical investigation to the rat inner ear cells with special attention to vestibular dark cells and endolymphatic sac. MATERIALS AND METHODS: We observed immunoreactivity of megalin under light and electron microscopy. The primary antibody was rabbit polyclonal antibody that had been raised against rat immunoaffinity-purified megalin. RESULTS: The luminal membrane and subapical area of dark cells in the semicircular canal were immunolabeled. The stainable substance in the endolymphatic space was strongly stained. The cytoplasm of epithelial cells was also stained in various patterns.

Ultrastructural co-localization of cochlin and type II collagen in the rat semicircular canal.

Cochlin and type II collagen are major constituents of the inner ear extracellular matrix. To investigate the morphological relation of cochlin and type II collagen in the rat semicircular canal, immuno-electronmicroscopic analysis was performed using the post-embedding immunogold method. Immunolabeling for cochlin was detected in the fibrillar substance underlying the supporting epithelium of the sensory cells and beneath the epithelial cells facing the endolymph in the semicircular canals. Immunolabeling for type II collagen was observed in the same fibrillar substance in the subepithelial area. The co-localization of cochlin and type II collagen in the fibrillar substance in the subepithelial area indicate that cochlin may play a role in the structural homeostasis of the vestibule acting in concert with the fibrillar type II collagen bundles.

Pattern of cochlear damage caused by short-term kanamycin application using the round window microcatheter method.

CONCLUSION: Short-term local application of kanamycin by the microcatheter method can control the region and severity of drug effect on the cochlea by changing the concentration and administration time. OBJECTIVES: To investigate the effect of short-term round window administration of kanamycin by the microcatheter method on cochlear stereociliary bundle loss in a guinea pig model. MATERIALS AND METHODS: Two concentrations and two time periods were used for drug administration to the inner ear. In groups of six animals, a total dose of 172.5 mg/ml or 345 mg/ml of kanamycin was instilled at the rate of 0.1 ml/h into the round window niche over either a 1 h or 2 h period by the microcatheter method. One group of six animals received a saline infusion as a control. The animals were sacrificed after 4 days and stereociliary bundle loss was observed by SEM. Functional changes were evaluated by auditory brainstem response. RESULTS: With regard to the severity of the damage, higher drug concentrations were associated with more severe effects. The severity of damage was the same when the same total dose was used; however, it was found that when the dose was administered over a longer period, the damage region was wider. The functional changes also corresponded with the morphological changes.

Pain patterns and mandibular dysfunction following experimental trapezius muscle pain.

AIMS: To clarify the effects of experimental trapezius muscle pain on the spread of pain and on jaw motor function. METHODS: In 12 male subjects aged 25 to 35 years, experimental pain was induced in the superior border of the trapezius muscle by injecting 0.5 mL of hypertonic (6%) saline. The control infusion consisted of a 0.5-mL isotonic (0.9%) saline solution. Pain intensity was evaluated on a visual analog scale (VAS). An experimental (EX) and a control (CT) injection were administered to the subjects in a randomized sequence. RESULTS: Pain intensity as scored on the VAS increased immediately after the EX injection and decreased gradually after reaching a peak of 68.0 +/- 16.1 mm at 60 seconds after injection. The VAS scores in the EX condition were significantly higher than after the CT condition from 30 to 330 seconds after injection (P < .05, analysis of variance [ANOVA]). Mean (+/- SD) maximal unassisted mouth opening before injection in the EX condition was 54 +/- 5.7 mm and decreased immediately after the injection, reaching a low of 47.8 +/- 5.1 mm. A gradual recovery to normal was then observed. This reduction of mouth opening in the EX condition was significant compared with the CT condition from immediately after the injection to 60 seconds after the injection (P < .05, ANOVA). According to the subjects, pain spread most often to the infra-auricular zone (n = 6), and the posterolateral part of the neck (n = 10). CONCLUSION: The present results suggest that experimental trapezius muscle pain can spread over a wide area and is also accompanied by a temporary reduction of mouth opening.

Dual-subtype FIV vaccine (Fel-O-Vax FIV) protection against a heterologous subtype B FIV isolate.

Vaccine trials were undertaken to determine whether the Fel-O-Vax FIV, a commercial dual-subtype (subtypes A and D) feline immunodeficiency virus (FIV) vaccine, is effective against a subtype B FIV isolate. Current results demonstrate the Fel-O-Vax FIV to be effective against a subtype B virus, a subtype reported to be the most common in the USA.

First total synthesis of a novel monoterpenoid isoquinoline alkaloid, (+/-)-alangine.

The structure including the stereochemistry of a novel monoterpenoid isoquinoline alkaloid, alangine, was confirmed by total synthesis via N-acyliminium cyclization to construct the isoquinoline skeleton and reductive cleavage of vinyl epoxide with Pd(0) catalyst.

Is AZT/3TC therapy effective against FIV infection or immunopathogenesis?

In vitro and in vivo prophylactic and therapeutic efficacy of AZT/3TC treatment was evaluated against feline immunodeficiency virus (FIV) infection. In vitro studies utilized FIV-infected peripheral blood mononuclear cells (PBMCs) or FIV-infected T-cell lines treated with AZT (azidothymidine) alone, 3TC alone, or AZT/3TC combination and tested for anti-FIV activity and drug toxicity. AZT/3TC combination had additive to synergistic anti-FIV activities in primary PBMC but not in chronically infected cell lines. In vivo studies consisted of four treatment groups (n=15) of SPF cats receiving AZT/3TC combination (5-75 mg/kg/drug PO BID for 8 or 11 weeks) and one control group (n=9) receiving oral placebo. Group I (n=6, 150 mg/kg/drug/day) was treated starting 3 days pre-FIV inoculation, whereas Group II (n=3, 150 mg/kg/drug/day) and Group III (n=3, 100 mg/kg/drug/day) treatments were simultaneous with FIV inoculation. Group IV treatment (n=3, 100 mg/kg/drug/day) was initiated 2 weeks post-FIV inoculation. All cats were monitored for drug toxicity and FIV infection. Eighty-three percent of cats in Group I and 33% of cats in Groups II and III were completely protected from FIV infection. A significant delay in infection and antibody seroconversion was observed in all unprotected cats from Groups I, II and III. Group IV cats had only a slight delay in FIV antibody seroconversion. Adverse drug reactions (anemia and neutropenia) were observed at high doses (100-150 mg/kg/drug/day) were reversible upon lowering the dose (20 mg/kg/drug/day). In contrast, AZT/3TC treatment had no anti-FIV activity in chronically infected cats. Furthermore, severe clinical symptoms caused by adverse drug reactions were observed in some of these cats. Overall, AZT/3TC treatment is effective for prophylaxis but not for therapeutic use in chronically FIV-infected cats.