Effect of wearing masks on odor detection and recognition

BACKGROUND

The effect of wearing masks on olfaction remains unclear.

OBJECTIVES

This study aimed to clarify the differences between the effects of no masks, surgical masks, and N95 respirator masks by conducting both identification and threshold olfaction tests.

METHODS

Young, healthy volunteers aged ≥ 18 years and < 30 years without awareness of apparent olfactory disorder were included. All participants filled out a questionnaire on olfaction and completed an acuity smell identification test (Open Essence test) and an olfactory threshold test (T&T olfactometry) while wearing no masks, surgical masks, or N95 respirator masks.

RESULTS

In the Open Essence tests, the no-mask group score was significantly higher than those of the surgical- and N95-mask groups. Using T&T olfactometry, the median-detection threshold of the no-mask group was significantly lower than that of the surgical-mask group, and the surgical-mask group threshold was significantly lower than that of the N95-mask group. Similar patterns were observed for the median-recognition threshold.

CONCLUSIONS

Wearing masks, especially an N95 mask, reduces the ability to detect and identify odors. This disadvantage should be considered by professionals such as healthcare workers, who require proper olfaction to perform appropriate tasks.

Fatty acid binding protein type 7 deficiency preserves auditory function in noise-exposed mice

Fatty acid-binding protein 7 (FABP7) is vital for uptake and trafficking of fatty acids in the nervous system. To investigate the involvement of FABP7 in noise-induced hearing loss (NIHL) pathogenesis, we used Fabp7 knockout (KO) mice generated via CRISPR/Cas9 in the C57BL/6 background. Initial auditory brainstem response (ABR) measurements were conducted at 9 weeks, followed by noise exposure at 10 weeks. Subsequent ABRs were performed 24 h later, with final measurements at 12 weeks. Inner ears were harvested 24 h after noise exposure for RNA sequencing and metabolic analyses. We found no significant differences in initial ABR measurements, but Fabp7 KO mice showed significantly lower thresholds in the final ABR measurements. Hair cell survival was also enhanced in Fabp7 KO mice. RNA sequencing revealed that genes associated with the electron transport chain were upregulated or less impaired in Fabp7 KO mice. Metabolomic analysis revealed various alterations, including decreased glutamate and aspartate in Fabp7 KO mice. In conclusion, FABP7 deficiency mitigates cochlear damage following noise exposure. This protective effect was supported by the changes in gene expression of the electron transport chain, and in several metabolites, including excitotoxic neurotransmitters. Our study highlights the potential therapeutic significance of targeting FABP7 in NIHL.

Effects of zinc deficiency on the regeneration of olfactory epithelium in mice

The olfactory epithelium can regenerate after damage; however, the regeneration process is affected by various factors, such as viral infections, head trauma, and medications. Zinc is an essential trace element that has important roles in organ development, growth, and maturation. Zinc also helps regulate neurotransmission in the brain; nevertheless, its relationship with olfactory epithelium regeneration remains unclear. Therefore, we used a severe zinc deficiency mouse model to investigate the effects of zinc deficiency on olfactory epithelium regeneration. Male wild-type C57BL/6 mice were divided into zinc-deficient and control diet groups at the age of 4 weeks, and methimazole was administered at the age of 8 weeks to induce severe olfactory epithelium damage. We evaluated the olfactory epithelium before and 7, 14, and 28 days after methimazole administration by histologically analyzing paraffin sections. RNA sequencing was also performed at the age of 8 weeks before methimazole administration to examine changes in gene expression caused by zinc deficiency. In the zinc-deficient group, the regenerated olfactory epithelium thickness was decreased at all time points, and the numbers of Ki-67-positive, GAP43-positive, and olfactory marker protein-positive cells (i.e. proliferating cells, immature olfactory neurons, and mature olfactory neurons, respectively) failed to increase at some time points. Additionally, RNA sequencing revealed several changes in gene expression, such as a decrease in the expression of extracellular matrix-related genes and an increase in that of inflammatory response-related genes, in the zinc-deficient group. Therefore, zinc deficiency delays olfactory epithelium regeneration after damage in mice.

Endoscopic Resection of Nasal Mucosal Melanoma Using Temporary Transseptal Access

Nasal mucosal melanoma (NMM) is a rare tumor with a poor prognosis. Although an endoscopic resection of malignant nasal tumor now becomes a treatment of choice when the surgical margin can be secured, it is still controversial. We report three cases of NMM that was successfully removed en bloc with clear margins by endoscopic surgery with temporal transseptal access. Cases of a 78-year-old woman, an 83-year-old man, and an 81-year-old man with NMM arising from the inferior turbinate who underwent endoscopic resection of the tumor are discussed in detail. We made temporal transseptal access using septal mucosal flaps. We moved the nasal cavity-occupying tumor to the contralateral side to create a working space to perform endoscopic en bloc resections. This technique is simple yet effective and less invasive than open craniofacial resections for removing malignancies arising from the inferior turbinate.

Effect of treatments for head and neck cancer on sinus shadow on computed tomography

OBJECTIVE

Head and neck surgeries may cause changes in the nasal airflow, and radiotherapy irreversibly damages paranasal sinus epithelial cells. Some chemotherapeutic drugs have been reported to negatively affect airway ciliary activity in mice, and chronic rhinosinusitis could be an adverse effect of head and neck cancer (HNC) treatment. To evaluate whether HNC treatment is a risk factor for developing sinonasal mucosal thickening that may reflect paranasal sinus inflammation, we compared pre- and post-treatment paranasal sinus computed tomography (CT) images of patients treated for HNC at a single university hospital.

METHODS

The patients who received curative treatment for HNC (oral, pharyngeal, and laryngeal cancers) and started receiving first-line therapy between January 2015 and December 2019 were included. Data on age, sex, primary lesion, clinical stage, treatment, smoking history, drinking history, comorbidities (diabetes and chronic lung disease), and pre- and post-treatment (three months and one year after the final treatment) paranasal sinus CT images were analyzed from medical records. Pre- and post-treatment paranasal sinus CT images were scored using the Lund-Mackay (LM) staging system.

RESULTS

In total, 245 patients participated in this study. Three months after the final treatment, 80.4% of patients had no change in their total LM scores (p=0.621). Almost 80% of patients who underwent total laryngectomy also had no change in their total LM scores (p=0.833). One-third of patients with nasopharyngeal cancer (NPC) had worse LM scores after treatment (5/15), although no significant difference was observed (p=0.171). None of the various factors collected were significantly related to changes in LM scores three months after the completion of treatment. One year after the final treatment, 211 patients were included and no significant changes in the pre-and post-LM scores were observed in the same analyses, while changes in LM scores were significantly different between T categories (T1-2 vs. T3-4) (p=0.020).

CONCLUSION

We found no significant changes in the LM scores after HNC treatment in all the patients, which implies that HNC treatment may not be an apparent risk factor for sinonasal mucosal inflammation.

Preoperative Endovascular Embolization in an Easily Bleeding Respiratory Epithelial Adenomatoid Hamartoma of the Olfactory Cleft: A Case Report

Respiratory epithelial adenomatoid hamartomas (REAHs) are rare tumors occurring in the nasal cavity and sinuses, and their etiology is unknown. REAH is a relatively recently established lesion and is often misdiagnosed as nasal polyposis or other tumors. Preoperative endovascular embolization for sinonasal tumors is now widely accepted as an effective method to reduce blood loss, soften the tumor, and facilitate surgical procedures. However, to the best of our knowledge, there are no reports of the requirement for preoperative embolization in the management of REAH. Here, we present a 70-year-old man with an easily bleeding REAH of the olfactory cleft, vascularized by branches of the bilateral internal and external carotid arteries. We removed the tumor endoscopically after preoperative embolization of the bilateral sphenopalatine arteries. Histological investigation revealed an intratumoral hemorrhage accompanying the REAH, with no evidence of a residual or recurrent tumor during the last follow-up at 3 months. In conclusion, accurate preoperative diagnosis and proper preoperative interventions such as embolization are needed for safe and adequate treatment of REAHs that have an abundant blood flow.

Efficacy and thyroidal effects of sunitinib in Japanese patients with metastatic renal cell carcinoma: Hypothyroidism and thyroid atrophy as potential biomarkers for sunitinib?

e16097

Background: Although hypothyroidism is a well-known adverse effect of sunitinib in western patients (pts) with metastatic renal cell carcinoma (MRCC), the effects on thyroid gland of sunitinib in Japanese pts still remain unclear. We therefore evaluated thyroid dysfunction and thyroid atrophy in Japanese RCC pts who received sunitinib. Methods: Fourteen (8 males, 6 females) of 51 pts who were treated in a phase II trial of sunitinib in Japanese pts with MRCC were included in this retrospective study. All 14 pts were euthyroid at baseline. The measurement of serum thyroid function test (fT3, fT4, TSH) was performed at the beginning of each sunitinib treatment cycle. A TSH concentration greater than 10 mU/L was considered as hypothyroidism regardless of subclinical or clinical. CT volumetry of the thyroid gland was performed utilizing the data obtained for tumor assessment in a phase II trial. Tumor response was evaluated based on the RECIST criteria. Results: 9 (64%) of 14 pts achieved RECIST-defined objective response (1 CR, 8 PRs). With regard to thyroid function, hypothyroidism was experienced by 11 (79%) pts. Three of 11 pts had Sunitinib-induced thyrotoxicosis before experiencing hypothyroidism. The mean time to development of hypothyroidism was 55 days (range 13–668). Six pts received typical doses of L-thyroxine. The response rate was 73% (8/11) in pts with hypothyroidism and 33% (1/3) in pts without. With regard to the volume of thyroid gland in 13 pts, 8 pts had more than 50% reduction comparing the volume at the baseline. Median reduction rate in volume of 13 pts was 57% (range 0–95%). Hypothyroidism was experienced by all 8 pts with more than 50% reduction in volume and 2 of 5 (40%) without. Furthermore, the response rate was 88% (7/8) in former pts and 40% (2/5) in latter pts. Conclusions: In addition to high anti-tumor efficacy, hypothyroidism and thyroid atrophy were commonly observed in Japanese MRCC pts who received sunitinib. Although further study should be required, these abnormal findings in thyroid gland following treatment with sunitinib may be potential biomarkers for tumor response to sunitinib.

[Table: see text]

[Quality control (QC) of CT on rail system (FOCAL Unit) with a micro-multi leaf collimator (mMLC) using new GafChromic film for stereotactic radiotherapy]

PURPOSE

Recent years, CT on rail system was reported to be useful as a tool for image-guided radiotherapy (IGRT). This system was clinically developed with the aim of stereotactic irradiation (STI) for brain, lung, liver, prostate and other sites. Quality assurance and quality control (QC) is an important issue in CT on rail system to assure geometric accuracies. The purpose of this study is to estimate the geometric accuracies of our CT on rail system using a detachable micro-multi leaf collimator (mMLC) with new type radiochromic films. Carrying out our original QC program, translational errors, setup reproducibility, beam misalignment and beam characteristics were evaluated.

METHODS AND MATERIALS

We have studied with CT on rail system (FOCAL unit, Toshiba Medical systems, Tokyo, Japan) and mMLC unit (Accuknife, Direx Inc., Tokyo, Japan). We have developed original alignment phantom and small steel markers (2 mm phi) were implanted on its surface at certain intervals. Firstly, we have evaluated the accuracy of self-moving CT gantry and CT resolutions for cranio-caudal directions by changing slice thickness. And then using the phantom, we have measured the accuracy and reproducibility of geometric isocenter of the linac side and the CT gantry side by scanning the phantom. We have also measured the geometric changes of the common treatment couch by weight-loaded test (up to 135 kgw). To estimate dosimetric and geometric accuracies with the mMLC unit, the misalignment of the beam axes (gantry, collimator and couch rotation axis), mMLC leaf positions, and dose distributions for the verification plan were measured with new type GafChromic films (GafChromic-RTQA, ISP Inc., USA) and cylindrical phantom. The dose characteristics of the GafChromic film were also evaluated.

RESULTS

The reproducibility of the self-moving CT gantry have a good agreement within 1 mm. Weight-load test have shown a good reliability within 2 mm at the common treatment couch. The translational precision of the common treatment couch was 0.0 +/- 0.1 mm at linac side and -0.2 +/- 0.5 mm at CT gantry side. The misalignments of beam axes have been kept within 0.4 mm at maximum. Gap test have shown the accuracies of the mMLC leaf positions, which is needed to keep within 1 mm by a routine calibration.

CONCLUSIONS

To practice quality control program for the FOCAL unit and the mMLC unit is essential for a regular interval to reduce systematic errors. New type radiochromic film would be useful for a verification tool as alternative to conventional film.

Fractionated stereotactic radiotherapy of brain metastases from renal cell carcinoma

PURPOSE

To retrospectively evaluate the effectiveness of fractionated stereotactic radiotherapy (FSRT) for brain metastases from renal cell carcinoma (RCC).

METHODS AND MATERIALS

From May 1983 to September 1998, 35 patients with brain metastases from RCC underwent radiotherapy at the National Cancer Center Hospital, Tokyo; 10 patients treated initially with FSRT (FSRT group); 11 with surgery followed by conventional radiotherapy (S/CR group); and 14 with conventional radiotherapy (CR group). Survival and local control rates were determined for patients who had an ECOG performance status of 0-2.

RESULTS

Overall median survival rate was 18 months, and actuarial 1- and 2-year survival rates were 57.6% and 31.0%, respectively. Median survival rates were 25.6 months for the FSRT group, 18.7 months for the S/CR group, and 4.3 months for the CR group. Significant prognostic factors associated with survival were age less than 60 years and good performance status. In patients treated with FSRT, imaging studies revealed that 21 of 24 tumors (88%) were locally controlled during a median follow-up time of 5.2 months (range 0.5-68). Actuarial 1- and 2-year local control rates were 89.6% and 55.2%, respectively. No patient suffered from acute or late complications during and following FSRT.

CONCLUSIONS

FSRT offers better tumor control and prolonged survival over the S/CR or CR groups, and should be considered as primary treatment for brain metastases from RCC. Patients under 60-years-old and those with a good performance status at the beginning of radiotherapy had a better prognosis.

Internalization of CD26 by mannose 6-phosphate/insulin-like growth factor II receptor contributes to T cell activation

CD26 is a T cell activation antigen known to bind adenosine deaminase and have dipeptidyl peptidase IV activity. Cross-linking of CD26 and CD3 with immobilized mAbs can deliver a costimulatory signal that contributes to T cell activation. Our earlier studies revealed that cross-linking of CD26 induces its internalization, the phosphorylation of a number of proteins involved in the signaling pathway, and subsequent T cell proliferation. Although these findings suggest the importance of internalization in the function of CD26, CD26 has only 6 aa residues in its cytoplasmic region with no known motif for endocytosis. In the present study, we have identified the mannose 6-phosphate/insulin-like growth factor II receptor (M6P/IGFIIR) as a binding protein for CD26 and that mannose 6-phosphate (M6P) residues in the carbohydrate moiety of CD26 are critical for this binding. Activation of peripheral blood T cells results in the mannose 6 phosphorylation of CD26. In addition, the cross-linking of CD26 with an anti-CD26 antibody induces not only capping and internalization of CD26 but also colocalization of CD26 with M6P/IGFIIR. Finally, both internalization of CD26 and the T cell proliferative response induced by CD26-mediated costimulation were inhibited by the addition of M6P, but not by glucose 6-phosphate or mannose 1-phosphate. These results indicate that internalization of CD26 after cross-linking is mediated in part by M6P/IGFIIR and that the interaction between mannose 6-phosphorylated CD26 and M6P/IGFIIR may play an important role in CD26-mediated T cell costimulatory signaling.

CD26/dipeptidyl peptidase IV differentially regulates the chemotaxis of T cells and monocytes toward RANTES: possible mechanism for the switch from innate to acquired immune response

CD26, a 110 kDa cell surface glycoprotein, exhibits dipeptidyl peptidase IV (DPPIV; EC 3.4.14.5) enzyme activity and plays an important role in T cell co-stimulation. In the present study, the function of CD26/DPPIV in transendothelial migration was examined using beta-chemokines as chemoattractants. When soluble recombinant CD26 (sCD26/DPPIV+) was added to the transendothelial chemotaxis system, chemotactic migration of T cells toward RANTES was significantly enhanced. Addition of sCD26 to 50 ng/ml of RANTES enhanced the migratory response by a factor of two compared to RANTES alone, whereas mutant soluble CD26 (mCD26), lacking the DPPIV enzyme activity, had no enhancing effect on RANTES-induced T cell migration. In the process of analyzing the mechanisms of the enhancement of T cell migration by sCD26, we showed that RANTES was cleaved by sCD26 under physiologic conditions at the precise site characteristic of its enzyme specificity. However, synthesized RANTES which lacks two N-terminal amino acids showed a chemotactic activity equivalent to full-length RANTES on T cells. Furthermore, addition of sCD26 showed enhancement of T cell migration induced by both forms of RANTES. In contrast to T cells, the truncated RANTES is inactive in chemotaxis of purified monocytes and supplement of sCD26 but not mCD26 reduced the migratory response of monocytes to RANTES. These results suggest that CD26/DPPIV differentially regulate the chemotactic response of T cells and monocytes to RANTES.

Radiation Complications Following Breast Conserving Therapy

BACKGROUND: Breast conserving therapy is being established as a standard therapeutic procedure for early breast cancer in Japan. However, the indications of radiotherapy and a standardized therapeutic procedure have not been established yet. In this study, complications following radiotherapy were evaluated in patients who had previously undergone breast conserving therapy at Tokushima University Hospital. METHODS From October 1989 to March 1996, 60 women with stage I or II breast cancer underwent radiation therapy after breast conserving surgery, and all patients were followed-up for a median of 27 months. Radiation morbidity scoring of the breast and adjacent organs was performed using the toxity criteria of the Radiation Therapy Oncology Group (RTOG) and European Organization for Research andTreatment of Cancer (EORTC). RESULTS: Only 1 patient developed local recurrence, and no distant metastasisor death was observed. The cause of recurrence in 1 case was considered to be due to extended intraductal component. Although transient dermal reaction was induced by irradiation of the breast, no side effects that may cause cosmetic problems were found. No serious radiation complications were found in the lungs, ribs, heart or other adjacent organs. CONCLUSION: The adverse reactions caused by irradiation does not reduce the merit of combined use of radiation therapy in breast conserving therapy, and therefore, are not the hesitation factor in application of radiotherapy.

Detection of virulent Rhodococcus equi in tracheal aspirate samples by polymerase chain reaction for rapid diagnosis of R. equi pneumonia in foals

Polymerase chain reaction (PCR)-based assays were developed to detect virulent Rhodococcus equi in transtracheal aspirate samples from sick foals showing respiratory signs. An oligonucleotide primer pair from the sequence of the virulence-associated 15- to 17-kDa antigen gene of the virulence plasmid in virulent R. equi was used to amplify a 564 bp region by PCR, and the result was confirmed by Southern blot hybridization. No positive reaction was seen in DNA from 13 different microorganisms typically found in the respiratory tract. In tracheal aspirates seeded with virulent R. equi, a visible band could detect 10 to 10(2) bacteria per PCR assay (10(3) to 10(4)/ml of the aspirate). Virulent R. equi was demonstrated in 31 of 42 transtracheal aspirates by culture and colony blot analysis, whereas a positive PCR result was observed in only 12 of the 31 culture positive samples. To prevent false-negative results, two methods were developed: a nested PCR and a PCR in combination with enrichment cultures of aspirates in the selective medium to increase the number of bacteria to 10(4)/ml or more. All of the PCR-negative and culture-positive samples were positive by the two methods. These results indicated that PCR-based assays provide a specific and sensitive means to detect virulent R. equi in tracheal aspirates of foals, and they are more rapid than the routine culture procedures for the diagnosis of R. equi pneumonia in foals.

Different regulatory effects of pentoxifylline on human T cell activation pathways

Pentoxifylline (PTX), a methylxanthine derivative, was examined for its effects on T cell proliferation and cytokine production stimulated by cross-linking anti-CD3 alone, anti-CD3 with PMA, anti-CD3 with anti-CD26, or anti-CD3 with anti-CD28 mAb, respectively. PTX at a 3.5 x 10(-5) M concentration significantly inhibited T cell proliferation and the production of tumor necrosis factor-alpha, interleukin-2, and interleukin-4. Moreover, this effect was selective for stimulation by cross-linking anti-CD3 with PMA, or anti-CD3 with anti-CD26, but not by cross-linking anti-CD3 with anti-CD28. These results suggest that the inhibitory effect of PTX on T cell activation involves the CD3 and CD26, but not the CD28 signal pathway.

[Eight cases of intracranial arteriovenous malformations treated by conventional radiation therapy]

We conducted radiotherapy in 8 cases of intracranial arteriovenous malformation that had difficult embolectomy and other surgery from 1983 to October, 1988. The results in 6 cases of dural arteriovenous malformation at the cavernous sinus were "marked effect" in 4 cases, "relapse" in 1 case, and "no effect" in 1 case. One case of dural arteriovenous malformation at the sigmoid venous sinus demonstrated only slight irradiation effect. No irradiation effect was observed in 1 case of cerebral arteriovenous malformation.

Streptomyces auranticolor Sp. Nov., a new anticoccidial antibiotics producer

A new species of Streptomyces is described and designated Streptomyces auranticolor (FERM-P No. 5365) which produces new anticoccidial antibiotics, designated as WS-5995 A and WS-5995 B. The organism is characterized by gray spore mass color, spiral spore chain with smooth spores, non-chromogenic reaction, soluble pigment, and carbon utilization characteristics. It differs from previously described streptomycetes on the basis of carbon utilization, and pigment production.

New anticoccidial antibiotics, WS-5995 A and B. I. Isolation and characterization

WS-5995 A, B and C are produced by a new strain of Streptomyces designated Streptomyces auranticolor. These antibiotics were purified by solvent extraction followed by chromatography on silica gel and then crystallized. WS-5995 A (C19H12O6, m.p., 289 approximately 291 degrees C) and WS-5995 B (C19H14O6, sublimation at 300 degrees C) protect chickens from infection with Eimeria tenella, a species of coccidia, which produces morbidity or mortality in chickens. WS-5995 C (C19H14O 7, m.p. 288 approximately 290 degrees C), a biologically inactive component, was found to be converted to WS-5995 A on treatment with trifluoroacetic anhydride.

Thiopeptin, a new feed additive antibiotic: microbiological and chemical studies

The thiopeptins are a new group of sulfur-containing peptide antibiotics produced by Streptomyces tateyamensis. The antibiotic consists of a major component (designated as thiopeptin B) and four minor ones (thiopeptins A(1) to A(4)). These components were isolated by solvent extraction from mycelium followed by chromatography on silica gel with various ratios of chloroform and methanol as elution solvents. Acid hydrolysis of each of the thiopeptin components yielded 1 mole of valine, 1 of threonine, 1 of cysteine, and 2 of alanine as amino acids. Each component of the thiopeptin A group has chemical and biological properties closely similar to those of thiopeptin B, but detailed characterization has established that thiopeptins A(1), A(3), and A(4) are new antibiotics. We could not obtain accurate data for determination of the uniqueness of A(2) because of insufficient sample. Thiopeptin has strong antibacterial activity against gram-positive bacteria and Mycoplasma, and exhibits no cross-resistance to major human-use antibiotics.