Intrathecally administered substance P activated the spinal defecation center and enhanced colorectal motility in anesthetized rats.

Noxious stimuli on the colorectum cause colorectal contractions through activation of descending monoaminergic pathways projecting from the supraspinal defecation center to the spinal defecation center. Since it is known that substance P is involved in the response to peripheral noxious stimuli in the spinal cord, we investigated the effects of intrathecally administered substance P at L6-S1 levels on colorectal motility in rats that were anesthetized with α-chloralose and ketamine. Intrathecally administered substance P enhanced colorectal motility, even after transection of the thoracic spinal cord at the T4 level. Severing the pelvic nerves, but not the colonic nerves, abolished substance P enhanced colorectal motility. In the spinal cord at L6-S1 levels, expression of mRNA coding neurokinin (NK) 1-3 receptors was detected by RT-PCR. Immunohistological experiments revealed that preganglionic neurons of the pelvic nerves express NK1 receptors, whereas expression of NK2 receptors was not found. In addition, substance P-containing fibers densely innervated around the preganglionic neurons expressing NK1 receptors. An intrathecally administered NK1 receptor antagonist (spantide) attenuated capsaicin-induced colorectal contractions. These results suggest that the colokinetic action of substance P is mediated by the NK1 receptor in the spinal defecation center. Our findings indicate that substance P may function as a neurotransmitter in the spinal defecation center.NEW & NOTEWORTHY We found that intrathecally administered substance P enhanced colorectal motility in anesthetized rats. Neurokinin (NK) 1 receptors, but not NK2 receptors, were detected in preganglionic neurons of the pelvic nerves. Blockade of NK1 receptors in the spinal cord attenuated the enhanced colorectal motility in response to intracolonic noxious stimuli. The findings indicate that substance P may function as a neurotransmitter in the spinal reflex pathway controlling defecation.

Anatomy and histology of the foramen of ovarian bursa opening to the peritoneal cavity and its changes in autoimmune disease-prone mice.

The ovarian bursa is a small peritoneal cavity enclosed by the mesovarium and mesosalpinx, which surrounds the ovaries and oviductal infundibulum in mammals. The ovarian bursa is considered as the structure facilitating the transport of ovulated oocytes into the oviduct. Our previous study revealed reduced oocyte pick-up function in the oviduct of lupus-prone MRL/MpJ-Faslpr/lpr mouse, suggesting the possibility of an escape of ovulated oocytes into the peritoneal cavity, despite the presence of an almost complete ovarian bursa in the mouse. In this study, we revealed anatomical and histological characteristics of the ovarian bursa in C57BL/6 N, MRL/MpJ, and MRL/MpJ-Faslpr/lpr mice. All strains had the foramen of ovarian bursa (FOB), with a size of approximately 0.04 to 0.12 cm2 , surrounded by the ligament of ovarian bursa (LOB), which is part of the mesosalpinx. The LOB was partially lined with the cuboidal mesothelial cells and consisted of a thick smooth muscle layer in all strains. In 6-month-old MRL/MpJ-Faslpr/lpr mice, in which the systemic autoimmune abnormality deteriorated and oocyte pick-up function was impaired, the size of the FOB tended to be larger than that of other strains. Additionally, in MRL/MpJ-Faslpr/lpr mice at 6 months of age, there was infiltration by numerous immune cells in the mesosalpinx suspending the isthmus; however, the LOB prevented severe inflammation and showed deposition of collagen fibers. These results not only indicate that the FOB is a common structure within mice, but also imply the physiological function of the LOB and its role in maintaining the microenvironment around the ovary, as well as regulating healthy reproduction.

Three-dimensional ultrastructure reconstruction of tendinous components at the bifurcation of the bovine superficial digital flexor tendon using array and STEM tomographies.

Tendons transmit force from muscle to bone for joint movement. Tenocytes are a specialized type of fibroblast that produces collagen fibrils in tendons. Their cytoplasmic processes form a network surrounding collagen fibrils to define a collagen fibre. Glycosaminoglycan (GAG) chains link collagen fibrils and adhere at the D-band of the collagen fibril. In this study, we used array and scanning transmission electron microscope (STEM) tomographies to reconstruct the three-dimensional ultrastructure of tenocytes, collagen fibres, collagen fibrils and GAG chains at the bifurcation of the bovine hindlimb superficial digital flexor tendon (SDFT). Collagen fibrils comprising a collagen fibre were not aligned uniformly and had at least two running directions. Spindle-shaped tenocytes were arranged along the long axis of a plurality of collagen fibres, where two groups of collagen fibrils with oblique directions to each other exhibited an oblique overlap of the two collagen fibril layers. Collagen fibrils with different running directions were observed in separating layers of about 300 nm in thickness and had diameters of 0-200 nm. About 40% of all collagen fibrils had a peak in the range of 20-40 nm. STEM analysis of the same site where the crossing of collagen fibres was observed by transmission electron microscopy demonstrated the outline of collagen fibrils with a clear D-banding pattern at a regular interval. Collagen fibrils were reconstructed three-dimensionally using continuous images acquired by STEM tomography, which confirmed that the collagen fibrils at the crossing sites did not orientate in layers, but were woven one by one. Higher magnification observation of GAG chains attached between the crossing collagen fibrils revealed numerous GAG chains arranged either vertically or obliquely on collagen fibrils. Furthermore, GAG chains at the cross of collagen fibrils connected the closest D-bands. GAG chains are thought to be universally present between collagen fibrils of the tendon. These observations by array and STEM tomographies increase our knowledge of the anatomy in the bifurcation of the bovine hindlimb SDFT and demonstrate the utility of these new imaging technologies.

Efficacy of the red blood cell distribution width for predicting the prognosis of Bell palsy: a pilot study.

The aim of this study was to investigate the association between RDW values and the prognosis of patients with Bell palsy in an effort to find a prognostic biomarker that predicts recovery from Bell palsy. We measured RDW and evaluated facial movement in 61 patients with Bell palsy aged 50 years and less. All patients were treated with a steroid plus an antiviral agent. Seven patients underwent surgery for facial nerve decompression. During the post-treatment period, patients with a Yanagihara grading score of 36 or more were regarded as having a satisfactory recovery. Patients were divided into two groups (recovered and unrecovered) according to their response to treatment, and several parameters, including the RDW, were measured for further analysis. RDW values were significantly higher in the unrecovered group than in the recovered group (13.5 ± 1.7 vs. 12.7 ± 0.7%, p = 0.046). In the multiple logistic regression model, RDW was the only factor associated with recovery from Bell palsy (odds ratio 1.93, 95% confidence interval 1.02-4.65, p = 0.042). Our preliminary study provides the first evidence that the red cell distribution width (RDW) can predict recovery from Bell palsy in patients aged 50 years and less. Further studies are necessary to elucidate the potential pathophysiological mechanisms for our findings.

Advanced surgical technique for invasive fungal sinusitis: endoscopic orbit-sinus combined approach.

BACKGROUND: Invasive fungal sinusitis is usually associated with poor prognosis, but no clear guidelines have been established for surgical treatment. Here, we report the development and application of the endoscopic orbit-sinus combined approach (EOSCA), a novel surgical technique to approach the nasal cavity and orbit concurrently, in patients with invasive fungal sinusitis with orbital infiltration. MATERIAL AND METHODS: Two patients with invasive fungal sinusitis infiltrating the orbit underwent EOSCA. Transnasal endoscopy was performed for maximum debulking of tissues infiltrated by fungi in the nasal cavity and orbit, before making an incision into the palpebral conjunctiva. An endoscope was then inserted into the orbit through the incision in the palpebral conjunctiva to remove adipose tissue and muscles that had been infiltrated by fungi from the orbital regions where the transnasal approach was difficult or impossible. Another surgeon assisted the procedure by operating an endoscope concurrently via the nasal cavity (four-hands technique). RESULTS: We were able to remove lesions safely and with precision, preserving visual acuity and a functional eyeball in both cases. Currently, the patients are alive, with no postoperative complications, recurrence, or disfigurement. CONCLUSIONS: This novel method shows promise as a safe and reliable surgical procedure for patients with invasive fungal sinusitis infiltrating into the orbit, with no postoperative complications, recurrence, or disfigurement.

Polysomnographic parameters during non-rapid eye movement sleep predict continuous positive airway pressure adherence.

The aim of this study was to investigate the potential polysomnographic predictors of CPAP adherence using polysomnographic parameters at the time of obstructive sleep apnea diagnosis that distinguished between REM and NREM sleep. This was a retrospective cross-sectional study of 173 patients. Patients who used CPAP for more than 4 hours per night for at least 70% of nights over a 6-month period were considered to have good adherence. The poor adherence group included those who had used CPAP for 6 months from initiation, but did not fulfill the definition of good adherence or gave up the treatment within 6 months of treatment initiation. Of the 173 participants, 44 patients had good CPAP adherence and 129 patients had poor adherence. Univariate analysis showed that patients with good adherence had significantly higher apnea-hypopnea index during NREM sleep (p = 0.043), oxygen desaturation index during NREM sleep (p = 0.011), and cumulative percentage of time spent at saturations below 90% (CT90) during NREM sleep (p < .001). In multiple logistic regression analysis including all variables, CT90 during NREM sleep was the only factor independently associated with CPAP adherence (odds ratio, 0.693; 95% confidence interval, 0.582-0.824; p <.0001). The area under the receiver-operating characteristic curve of CT90 during NREM sleep was 0.823 (95% confidence interval, 0.745-0.901).Evaluating NREM sleep is important in reliably predicting CPAP adherence using polysomnographic parameters. CT90 during NREM sleep was the best predictor of CPAP adherence.

Isolation and genomic characterization of a novel orthoreovirus from a brown-eared bulbul (Hypsipetes amaurotis) in Japan.

Five species, Mammalian orthoreovirus, Avian orthoreovirus (ARV), Nelson Bay orthoreovirus (NBV), Baboon orthoreovirus and Reptilian orthoreovirus, have been identified in the genus Orthoreovirus. Their genomes each consist of 10 dsRNA segments. A novel orthoreovirus was isolated from the haemorrhagic intestine of a dead brown-eared bulbul (Hypsipetes amaurotis) in Japan. The virus formed syncytia in Caco-2 and Vero cells. Electron microscopy revealed non-enveloped capsids of ~70 nm diameter, which were characteristic of reoviruses. Complete genomic sequences were determined. The S1 segment was tricistronic and encoded three proteins, p10, p17 and σC, as in the two species ARV and NBV. Sequence and phylogenetic analyses showed that the virus was similar to ARV and NBV, but was located on a phylogenetic branch different from that of ARV and NBV. The virus had the closest phylogenetic relationship to two reovirus strains: SSRV from a Steller sea lion in Canada and PsRV Ge01 from a psittaciform bird in Europe. The 10 RNA segments had a 3' pentanucleotide sequence (UCAUC-3') conserved amongst all members of the genus Orthoreovirus, and a unique 5' terminal heptasequence (5'-GCUUUUC) that was the same as those of SSRV and PsRV Ge01. These results suggested that the novel virus might form a new species with the two strains in the genus Orthoreovirus.

The association between hearing impairment and polymorphisms of genes encoding inflammatory mediators in Japanese aged population.

BACKGROUND: Aging process is accompanied by a chronic sub-clinical systemic inflammation. This study aimed to assess the association between hearing impairment and polymorphisms of genes encoding cytokines deeply-committed to the inflammatory response and immune homeostasis in an elderly Japanese population. Data were collected in the Longitudinal Study of Aging surveyed biennially between 1997 and 2010. The participants without any missing information at baseline were 1,957 individuals, and the gross accumulated number of 8,675 subjects (40-89 years of age) was analyzed. Two hearing impairment criteria were taken as the better ear pure-tone average (PTABE) greater than 25 dB and greater than 40 dB. We analyzed cumulative data using generalized estimating equations to investigate the effect of 9 polymorphisms, namely, tumor necrosis factor (TNF) α, rs1800630; TNF receptor super family (TNFRSF) 1B, rs1061624; interleukin (IL)-1A, rs1800587; IL-1B, rs16944; IL-4R, rs1801275; IL-6, rs1800796; IL-10, rs1800872; IL-1 receptor-associated kinase 1 (IRAK1), rs1059702; C reactive protein (CRP), rs1130864. RESULTS: The odds ratios for the hearing impairment (PTABE >25 dB) risk under additive genetic model were significant in TNF-α rs1800630 and TNFRSF1B rs1061624, which were respectively 1.172 (confidence interval [CI]: 1.005-1.367), 1.211 (CI: 1.053-1.392) in model after adjustment for possible confounders. Using the criterion of PTABE >40 dB as disabling hearing impairment, the association remains significant in TNFRSF1B rs1061624, but not in TNF-α rs1800630. No other polymorphisms showed a significant association. CONCLUSIONS: The present population-based cohort study demonstrated that TNF-α rs1800630 and TNFRSF1B rs1061624 contributed to the incremental risk of hearing impairment in the elderly. TNF-α and TNF receptor interactions play a pivotal role in the pathogenesis of the inflammatory response, and also cause programmed cell death and cell proliferation. The present observation implied the signalling cascades of TNF were involved in ear aging.

A rare case of middle ear adenoma.

Middle ear adenoma is a rare disease that is thought to originate in the middle ear mucosa. It occurs over a wide age range, has no gender predilection, and is not characterized by specific symptoms or findings. The most frequent complaints are unilateral hearing loss and ear fullness. We report a 48-year-old woman with middle ear adenoma who had a history of unilateral ear fullness and hearing loss on the left side. Middle ear adenoma was suspected following a biopsy performed under local anesthesia. To remove the tumor, the patient underwent a left postauricular canal wall-up tympanoplasty type IIIc. Microscopic examination and immunohistochemistry confirmed a middle ear adenoma. In this case, we diagnosed the lesion as middle ear adenoma with neuroendocrine differentiation on the basis of the pathological findings. The patient has shown no recurrence for almost 5 years, but since this adenoma showed neuroendocrine differentiation, long-term observation is required.

Downregulation of cytochrome P450scc as an initial adverse effect of adult exposure to diethylstilbestrol on testicular steroidogenesis.

Reproductive toxicities and endocrine disruptions caused by chemicals in adult males are still poorly understood. It is our objectives to understand further details of the initial adverse effects leading severe testicular toxicities of a pharmaceutical endocrine disruptor, diethylstilbestrol (DES). Downregulations of both testicular regulatory proteins, such as the steroidogenic acute regulatory protein (StAR) and the peripheral benzodiazepine receptor (PBR), which play important roles in the transport of cholesterol into the mitochondria, and cytochrome P450 mediating the cholesterol side chain cleavage reaction (P450scc), were observed in the rat orally administered DES (340 µg/kg/2 days) for 2 weeks. We found that after only 1 week treatment with DES, the blood and testicular testosterone (TS) levels were drastically decreased without abnormalities of the StAR and PBR; however, the protein and mRNA levels of P450scc were diminished. Decrease in the conversion rate of cholesterol to pregnenolone was delayed in the in vitro assay using the testicular mitochondrial fraction from the rat treated with DES for 1 week. When the precursors in TS biosynthesis containing the testis were identified and determined by liquid chromatography-mass spectrometry analysis, decreased levels of all precursors except cholesterol were observed. In conclusion, suppressed cytochrome P450scc expression in adult male rat was identified as an initial target of DES in testicular steroidogenesis disorder leading reproductive toxicities.

[A clinical study of acute epiglottitis in adults].

Acute epiglottitis may trigger death because of serious airway obstruction. It is necessary to perform emergency and accurate airway intervention. In this retrospective study we present 216 cases of acute epiglottitis in adults. Airway management was done in 39 cases (18.1%), but most cases were treated conservatively. The mean patient age was 53 years and the male-to-female ratio was 1.9 to 1.0. The most frequent symptoms were sore throat (88%). The mean duration from symptom onset to consultation to our hospital was 1.9 days in the airway management group and 2.9 days in the conservatively treated group, which was statistically significant (p<0.05). Focusing on epiglottal swelling seen under the flexible laryngoscope, the percentage of airway management was 52.6% for swelling of the unilateral false vocal cords and 12.9% for swelling of the aryepiglottic fold. A statistically significant difference was also seen in complaints of respiratory difficulties (p<0.01), the rise of WBC (p<0.01), the rise of CRP (p<0.01), and diabetes mellitus (p<0.01).

Morphological and biochemical characterization of Holstein cow skin at the tail root region susceptible to Chorioptes bovis and texanus parasitism.

Cattle mange causes extreme itchiness, and the associated stress is an animal welfare concern that leads to economic losses due to decreased cattle productivity and deworming costs. This study investigated the reason why Chorioptic mites, C. bovis and C. texanus, preferentially infest the tail root region (rTR) and performed histological and biochemical analysis focusing on the volatile components of host odors that serve as the starting point for infestation of parasitic arthropods. Skin samples were taken from the rTR, lateral abdominal, and central masseteric, with the latter two designated as comparison sites. The two and three-dimensional histological analysis measured each sebaceous and sweat gland percentage per unit volume. The q-PCR analyzed the expression levels of ALDH1A1 and LOC785756, which are genes associated with volatile odoriferous compounds that serve as repellency and attractive messengers for ticks. Immunohistochemistry stained three sites with anti-androgen binding protein beta-like (ABPß-like), encoded by LOC785756, antibody. The three-dimensional analysis showed that sebaceous glands in the rTR tend to be more continuous and existed in larger masses than in other regions. The expression level of LOC785756 was significantly higher in the rTR, and immunohistochemistry revealed the presence of ABPß-like in the sebaceous gland with strong positive signals in the rTR. These results suggest that C. bovis/texanus selectively infests the rTR because that skin has well-developed sebaceous glands, including a large amount of ABPß-like, which acts as a mite attractant.

The histopathological features of the surgical endometriosis model using systemic autoimmune disease-prone mice.

Endometriosis is a common gynecological disease that affects women of reproductive age in which the uterine endometrium grows outside the uterus. Origin of the ectopic endometrium is thought to be the retrograde endometrium through the oviducts. However, factors that determine the adherence and proliferation of the ectopic endometrium have not been revealed. Importantly, systemic autoimmune diseases are considered a key factor in the endometriosis onset. Herein, we established a surgical endometriosis rodent model using autoimmune disease-prone MRL/MpJ-Faslpr/lpr (MRL/lpr) and MRL/+ mice to provide basic evidence of the relationship between autoimmune disease and endometriosis. Endometriosis lesions were successfully induced in two regions after transplanting uterine tissues from donor mice into the peritoneal cavity of recipient mice: the peritoneum or adipose tissue around the transplantation point (proximal lesions) and the gastrosplenic ligament or intestinal mesentery far from the transplantation site (distal lesions). Distal lesions were observed only in MRL/lpr mice, whereas endometriosis lesions showed no genotype- or region-related differences in the histology and distribution of sex hormone receptors and T cells. In contrast, transplanted uterine tissues in donor MRL/lpr mice exhibited a large infiltration of T cells in the lamina propria. Splenomegaly was more common in recipient than that in donor MRL/lpr mice. These results suggest that the infiltration of endogenous T cells in the endometrium alters the growth features of ectopic endometrium, possibly affecting the severity of endometriosis in patients with systemic autoimmune diseases.

LOV2-based photoactivatable CaMKII and its application to single synapses: Local Optogenetics.

Optogenetic techniques offer a high spatiotemporal resolution to manipulate cellular activity. For instance, Channelrhodopsin-2 with global light illumination is the most widely used to control neuronal activity at the cellular level. However, the cellular scale is much larger than the diffraction limit of light (<1 µm) and does not fully exploit the features of the "high spatial resolution" of optogenetics. For instance, until recently, there were no optogenetic methods to induce synaptic plasticity at the level of single synapses. To address this, we developed an optogenetic tool named photoactivatable CaMKII (paCaMKII) by fusing a light-sensitive domain (LOV2) to CaMKIIα, which is a protein abundantly expressed in neurons of the cerebrum and hippocampus and essential for synaptic plasticity. Combining photoactivatable CaMKII with two-photon excitation, we successfully activated it in single spines, inducing synaptic plasticity (long-term potentiation) in hippocampal neurons. We refer to this method as "Local Optogenetics", which involves the local activation of molecules and measurement of cellular responses. In this review, we will discuss the characteristics of LOV2, the recent development of its derivatives, and the development and application of paCaMKII.

Oviduct Histopathology of Internal Laying and Egg-Bound Syndrome in Laying Hens.

In the egg industry, common reproductive disorders, such as internal laying and egg-bound syndrome, not only reduce egg productivity but also cause deaths in severe cases. In this study, we focused on the oviduct histology of the pathogenesis of internal laying and egg-bound syndrome. We divided the aged laying hens into four groups according to the observation of the abdominal cavity and oviductal lumen: healthy, internal laying, egg-bound, and intercurrent. The percentages of healthy, internal laying, egg-bound, and intercurrent groups were 55%, 17.5%, 15%, and 12.5%, respectively. In all parts of the oviduct (i.e., infundibulum, magnum, isthmus, and uterus), the oviductal epithelium was composed of ciliated epithelial cells and secretory cells. The epithelial region lacking cilia was larger in the entire oviduct of the internal laying, and intercurrent groups than in the healthy group. In the internal laying, egg-bound, and intercurrent groups, significant T-cell infiltration was observed in the lamina propria of the entire oviduct. The morphological alteration of ciliated epithelial cells in the oviducts caused by inflammation may be the underlying cause of the pathogenesis of internal laying and egg-bound syndrome.

In vivo three- and four-photon fluorescence microscopy using a 1.8 µm femtosecond fiber laser system.

Multiphoton microscopy has enabled us to image cellular dynamics in vivo. However, the excitation wavelength for imaging with commercially available lasers is mostly limited between 0.65-1.04 µm. Here we develop a femtosecond fiber laser system that produces ∼150 fs pulses at 1.8 µm. Our system starts from an erbium-doped silica fiber laser, and its wavelength is converted to 1.8 µm using a Raman shift fiber. The 1.8 µm pulses are amplified with a two-stage Tm:ZBLAN fiber amplifier. The final pulse energy is ∼1 µJ, sufficient for in vivo imaging. We successfully observe TurboFP635-expressing cortical neurons at a depth of 0.7 mm from the brain surface by three-photon excitation and Clover-expressing astrocytes at a depth of 0.15 mm by four-photon excitation.

The association of food intake on the development of hearing impairment after middle age among Japanese community dwellers.

OBJECTIVES: This study aimed to determine whether food intake modifies the risk of developing hearing impairment (HI) in Japanese adults in their 40s. METHODS: Data for individuals who were in their 40s with no HI at baseline and had participated in the survey multiple times were extracted from the National Institute for Longevity Sciences, Longitudinal Study of Aging. A total of 1846 samples observed for up to 11.5 years in 421 participants were included in the analyses. The average 3-day food intake was calculated. HI is defined as a pure-tone average of the better ear at frequencies of 0.5, 1, 2, and 4 kHz greater than 25 dB. The risk of developing HI in the 18 food groups was calculated longitudinally using multivariable cumulative data analyses. RESULTS: Even after adjusting basic confounding factors, food groups, and baseline hearing level, significant associations were found between beverage consumption and risk increments for HI (odds ratio [OR] = 2.374, 95% confidence interval [CI]:1.141-4.940) and also between mushroom intake and risk reduction (OR = 0.215, 95% CI:0.069-0.667). Other foods did not consistently show significant results when the combination of analysis variables were changed. CONCLUSIONS: Although the effect of food on hearing is modest to the extent that the significance varies with the variables used in the analysis, the intake of beverages and mushrooms could potentially modify the risk of developing HI after middle age.

Artesunate and cisplatin synergistically inhibit HNSCC cell growth and promote apoptosis with artesunate­induced decreases in Rb and phosphorylated Rb levels.

In the treatment of head and neck cancer, cisplatin is often used as a therapeutic agent; however, its efficacy is limited and it can cause renal dysfunction as an adverse effect. For this reason, the use of cisplatin is limited in elderly patients with reduced renal function. Recently, artemisinin, which was developed as an antimalarial drug, was found to have antitumor effects and is effective in combination with other anticancer drugs. In the present study, the antitumor effects of artemisinin and its derivatives as well as their combination with cisplatin and iron on head and neck squamous cell carcinoma cell lines, were investigated. Cell viability was determined by a cell viability assay, the cell cycle was analyzed by flow cytometry, cell death was assessed with annexin V and propidium iodide staining, and western blotting was used to analyze retinoblastoma protein (Rb), phosphorylated (p­)Rb, and other cell cycle­associated molecules. A total of four artemisinin compounds were examined and it was found that artesunate and dihydroartemisinin had a significant inhibitory effect on growth. It was also identified that the combination of artesunate, cisplatin, and iron inhibited cell proliferation and caused S/G2­M cell cycle arrest. In addition, western blotting of Rb, a molecule involved in the cell cycle, showed that artesunate induced the loss of not only Rb but also p­Rb. These results suggested that artesunate is a useful drug in combination with cisplatin.

Relationship between cognitive domains and hearing ability in memory clinic patients: How did the relationship change after 6 months of introducing a hearing aid?

OBJECTIVE: We aimed to evaluate the relationship between hearing ability and cognitive domains and determine how the relationship changes after 6 months of introducing a hearing aid. METHODS: We conducted a 6-month hearing aid lending study between September 2014 and March 2019, including 59 older participants who visited the Memory Clinic at the National Center for Geriatrics and Gerontology. The hearing level was assessed using pure tone audiometry. Speech intelligibility was measured using the monosyllabic word discrimination score. We assessed the relationship between hearing ability and cognitive domains using the Mini-Mental State Examination (MMSE) total score and four subscale scores (orientation, memory, attention, and language). Differences in the cognitive function between baseline (pre-) and 6 months later (post-) after introducing a hearing aid were also assessed. RESULTS: The pre-orientation score was significantly associated with the pure-tone average (p = 0.013), and the pre-language score was significantly associated with speech intelligibility (p = 0.006) after adjusting for confounders. None of the MMSE subscale scores were significantly different between pre- and post-scores, however, an expectation of improvement with continuous hearing aid use was implied in the attention domain. CONCLUSION: We found a significant association between hearing ability and cognitive domains in individuals whose cognitive functions were not considered healthy. The presence of a potential relationship between cognitive domains, hearing ability, and auditory compensation is suggested.

Concerted and adaptive alignment of decorin dermatan sulfate filaments in the graded organization of collagen fibrils in the equine superficial digital flexor tendon.

The equine superficial digital flexor tendon (SDFT) has a graded distribution of collagen fibril diameters, with predominantly small-diameter fibrils in the region of the myotendinous junction (MTJ), a gradual increase in large-diameter fibrils toward the osteotendinous junction (OTJ), and a mixture of small- and large-diameter fibrils in the middle metacarpal (MM) region. In this study, we investigated the ultrastructure of the SDFT, to correlate the spatial relationship of the collagen fibrils with the graded distribution. The surface-to-surface distances of pairs of fibrils were found to be almost constant over the entire tendon. However, the center-to-center distances varied according to fibril diameter. Decorin is the predominant proteoglycan in normal mature tendons, and has one dermatan sulfate (DS) or chondroitin sulfate (CS) filament as a side chain which is associated with the surfaces of the collagen fibrils via its core protein. We identified a coordinated arrangement of decorin DS filaments in the equine SDFT. The sizes of the decorin DS filaments detected by Cupromeronic blue staining showed a unique regional variation; they were shortest in the MM region and longer in the MTJ and OTJ regions, and a considerable number of filaments were arranged obliquely to adjacent collagen fibrils in the MTJ region. This regional variation of the filaments may be an adaptation to lubricate the interfibrillar space in response to local mechanical requirements. The results of this study suggest that the MTJ region, which receives the muscular contractile force first, acts as a buffer for mechanical forces in the equine SDFT.