Effects of high antibiotic concentrations applied to continuous local antibiotic perfusion on human bone tissue-derived cells.

Aims: Continuous local antibiotic perfusion (CLAP) has recently attracted attention as a new drug delivery system for orthopaedic infections. CLAP is a direct continuous infusion of high-concentration gentamicin (1,200 µg/ml) into the bone marrow. As it is a new system, its influence on the bone marrow is unknown. This study aimed to examine the effects of high-concentration antibiotics on human bone tissue-derived cells. Methods: Cells were isolated from the bone tissue grafts collected from six patients using the Reamer-Irrigator-Aspirator system, and exposed to different gentamicin concentrations. Live cells rate, apoptosis rate, alkaline phosphatase (ALP) activity, expression of osteoblast-related genes, mineralization potential, and restoration of cell viability and ALP activity were examined by in vitro studies. Results: The live cells rate (the ratio of total number of cells in the well plate to the absorbance-measured number of live cells) was significantly decreased at ≥ 500 µg/ml of gentamicin on day 14; apoptosis rate was significantly increased at ≥ 750 µg/ml, and ALP activity was significantly decreased at ≥ 750 µg/ml. Real-time reverse transcription-polymerase chain reaction results showed no significant decrease in the ALP and activating transcription factor 4 transcript levels at ≥ 1,000 µg/ml on day 7. Mineralization potential was significantly decreased at all concentrations. Restoration of cell viability was significantly decreased at 750 and 1,000 µg/ml on day 21 and at 500 µg/ml on day 28, and ALP activity was significantly decreased at 500 µg/ml on day 28. Conclusion: Our findings suggest that the exposure concentration and duration of antibiotic administration during CLAP could affect cell functions. However, further in vivo studies are needed to determine the optimal dose in a clinical setting.

Effect of low-intensity pulsed ultrasound on osteogenic differentiation of human induced membrane-derived cells in Masquelet technique.

INTRODUCTION: The Masquelet technique is a relatively new method for large bone defect treatment. In this technique, grafted bone tissue is used, and after the cement is removed, the induced membrane (IM; that form around the cement spacers placed in the bone defect region) is thought to play an important role in promoting bone formation. On the other hand, low-intensity pulsed ultrasound (LIPUS) is known to promote fracture healing and angiogenesis through mechanical stimulation. This study aimed to investigate the in vitro effects of LIPUS on the osteogenic differentiation of human induced membrane-derived cells (IMCs). METHODS: Seven patients who had been treated using the Masquelet technique were enrolled. The IM was harvested during the second stage of the technique. IMCs were isolated, cultured in growth medium, and then divided into two groups: (1) control group, IMCs cultured in osteogenic medium without LIPUS, and (2) LIPUS group, IMCs cultured in osteogenic medium with LIPUS treatment. Adherent cells from the IM samples were harvested after the first passage and evaluated for cell surface protein expression using immunostaining. A cell proliferation assay was used to count the number of IMCs using a hemocytometer. Osteogenic differentiation capability was assessed using an alkaline phosphatase (ALP) activity assay, Alizarin Red S staining, and real-time reverse transcription-polymerase chain reaction. RESULTS: Cell surface antigen profiling revealed that the IMCs contained cells positive for the mesenchymal stem cell-related markers CD73, CD90, and CD105. No significant difference in cell numbers was found between the control and LIPUS groups. The ALP activity of IMCs in the LIPUS group was significantly higher than that in the control group on days 7 and 14. Alizarin red S staining intensity was significantly higher in the LIPUS group than in the control group on day 21. Runx2 and VEGF expression was significantly upregulated on days 7 and 14, respectively, compared with levels in the control group. CONCLUSION: We demonstrated the significant effect of LIPUS on the osteogenic differentiation of human IMCs. This study indicates that LIPUS can be used as an additional tool for the enhancement of the healing process of the Masquelet technique.

Imaging Diagnosis, Prevalence, and Clinical Outcomes of Arthroscopic Surgery for Anterior Inferior Iliac Spine Impingement: A Systematic Review and Meta-analysis.

Background: Subspine impingement, or anterior inferior iliac spine (AIIS) impingement, is a type of extra-articular pathology associated with femoroacetabular impingement syndrome and often requires subsequent arthroscopic surgery. Purpose: To examine the diagnostic accuracy, prevalence, and clinical outcomes of arthroscopic treatment for AIIS impingement. Study Design: Systematic review; Level of evidence, 4. Methods: The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 checklist was applied. We searched for studies on the prevalence, diagnostic accuracy, and results of surgical treatment for AIIS impingement. For each included study, data synthesis and statistical analysis were performed to identify pooled prevalence, calculate clinical outcome scores, and estimate adverse events. The QUADAS (a quality assessment tool for diagnostic accuracy studies) was used to assess the quality of the diagnostic accuracy studies, and the Risk of Bias Assessment tool for Nonrandomized Studies was used to assess the quality of the studies on arthroscopic treatment efficacy. Results: Out of an initial 791 studies, 23 were included. AIIS impingement was diagnosed by plain radiography with 76% to 86% sensitivity, 3-dimensional computed tomography with 80% to 81.8% sensitivity, magnetic resonance imaging with 80% sensitivity, and ultrasound with 92.5% sensitivity. For patients who underwent hip arthroscopy, the pooled prevalence of AIIS impingement was 18%. Significant improvement between pre- and postoperative clinical outcomes was observed: 25.75 points for the modified Harris hip score (mHHS), 46.88 points for the Hip Outcome Score-Sport subscale, 20.85 points for the Nonarthritic Hip Score, and -2.92 points for the pain visual analog scale. The minimal clinically important difference on the mHHS was exceeded by 94% of patients. The pooled incidence of surgical complications was 1%. Of 6 included studies on diagnostic accuracy, 2 were identified as having a low risk of bias, and 4 included >2 factors with a high risk of bias. All 9 included studies on treatment outcomes had at least 1 factor with a high risk of bias. Conclusion: Several imaging modalities assist in the diagnosis of AIIS impingement. The overall prevalence of AIIS impingement in patients that underwent hip arthroscopy was 18%. Clinical outcomes after arthroscopic AIIS decompression were generally favorable, with a relatively low rate of surgical complications.

Human Non-Hypertrophic Nonunion Tissue Contains Osteoblast Lineage Cells and E-BMP-2 Activates Osteogenic and Chondrogenic Differentiation.

In this study, we examined the proliferation capability and osteogenic and chondrogenic differentiation potential of non-hypertrophic nonunion cells (NHNCs), and the effect of Escherichia coli-derived BMP-2 (E-BMP-2) on them. We enrolled five patients with non-hypertrophic nonunion. NHNCs isolated from nonunion tissue sampled during surgery were cultured, passaged, counted every 14 days, and analyzed. NHNCs were homogenous fibroblastic adherent cells and long-lived through at least 10 passages, with a slight decline. The cells were consistently positive for mesenchymal stem cell-related markers CD73 and CD105, and negative for the hematopoietic markers CD14 and CD45. NHNCs could differentiate into osteoblast lineage cells; however, they did not have strong calcification or sufficient chondrogenic differentiation capability. E-BMP-2 did not affect the proliferative capability of the cells but improved their osteogenic differentiation capability by increasing alkaline phosphatase activity and upregulating the gene expression of osterix, bone sialoprotein, and osteocalcin. E-BMP-2 enhanced their chondrogenic differentiation capability by upregulating the gene expression of aggrecan and collagen type II. We showed, for the first time, that NHNCs have the capacity to differentiate into osteoblast-lineage cells, although the chondrogenic differentiation potential was poor. Local application of E-BMP-2 with preservation of nonunion tissue is a potential treatment option for non-hypertrophic nonunion.

The utility of texture analysis of kidney MRI for evaluating renal dysfunction with multiclass classification model.

We evaluated a multiclass classification model to predict estimated glomerular filtration rate (eGFR) groups in chronic kidney disease (CKD) patients using magnetic resonance imaging (MRI) texture analysis (TA). We identified 166 CKD patients who underwent MRI comprising Dixon-based T1-weighted in-phase (IP)/opposed-phase (OP)/water-only (WO) images, apparent diffusion coefficient (ADC) maps, and T2* maps. The patients were divided into severe, moderate, and control groups based on eGFR borderlines of 30 and 60 mL/min/1.73 m2. After extracting 93 texture features (TFs), dimension reduction was performed using inter-observer reproducibility analysis and sequential feature selection (SFS) algorithm. Models were created using linear discriminant analysis (LDA); support vector machine (SVM) with linear, rbf, and sigmoid kernels; decision tree (DT); and random forest (RF) classifiers, with synthetic minority oversampling technique (SMOTE). Models underwent 100-time repeat nested cross-validation. Overall performances of our classification models were modest, and TA based on T1-weighted IP/OP/WO images provided better performance than those based on ADC and T2* maps. The most favorable result was observed in the T1-weighted WO image using RF classifier and the combination model was derived from all T1-weighted images using SVM classifier with rbf kernel. Among the selected TFs, total energy and energy had weak correlations with eGFR.

Contrast Enhancement of the Normal Infundibular Recess Using Heavily T2-weighted 3D FLAIR.

PURPOSE: The purpose of the present study was to evaluate contrast enhancement of the infundibular recess in the normal state using heavily T2-weighted 3D fluid-attenuated inversion recovery (FLAIR) (HT2-FLAIR). METHODS: Twenty-six patients were retrospectively recruited. We subjectively assessed overall contrast enhancement of the infundibular recess between postcontrast, 4-hour (4-h) delayed postcontrast, and precontrast HT2-FLAIR images. We also objectively conducted chronological and spatial comparisons by measuring the signal intensity (SI) ratio (SIR). Chronological comparisons were performed by comparing SI of the infundibular recess/SI of the midbrain (SIRIR-MB). Spatial comparisons were conducted by comparing SI on postcontrast HT2-FLAIR/SI on precontrast HT2-FLAIR (SIRPost-Pre) of the infundibular recess with that of other cerebrospinal fluid (CSF) spaces, including the superior part of the third ventricle, lateral ventricles, fourth ventricle, and interpeduncular cistern. RESULTS: In the subjective analysis, all cases showed contrast enhancement of the infundibular recess on both postcontrast and 4-h delayed postcontrast HT2-FLAIR, and showed weaker contrast enhancement of the infundibular recess on 4-h delayed postcontrast HT2-FLAIR than on postcontrast HT2-FLAIR. In the objective analysis, SIRIR-MB was the highest on postcontrast images, followed by 4-h delayed postcontrast images. SIRPost-Pre was significantly higher in the infundibular recess than in the other CSF spaces. CONCLUSION: The present results demonstrated that the infundibular recess was enhanced on HT2-FLAIR after an intravenous gadolinium injection. The infundibular recess may be a potential source of the leakage of intravenously administered gadolinium into the CSF.

Novel composite cement containing the anti-microbial compound CPC-Montmorillonite.

OBJECTIVES: The aim of this study was to evaluate the mechanical properties, bonding performance and anti-microbial activity of a novel composite cement containing cetylpyridinium chloride (CPC) modified montmorillonite ('CPC-Mont'), and using these parameters to determine the optimal particle size and concentration of CPC-Mont the composite cement can be loaded with. METHODS: CPC-Mont particles with a median diameter of 30 and 7 µm were prepared and added to a composite cement at a concentration of 2, 3, 4, 5 and 7.5 wt%. Mechanical properties and bonding performance of the experimental composite cements were evaluated by 3-point bending and micro-tensile bond-strength testing. The amount of CPC released from the cement disks was quantified using a UV-vis recording spectrophotometer. The anti-biofilm activity was studied using scanning electron microscopy (SEM). RESULTS: Adding 30-µm CPC-Mont decreased the mechanical properties and bonding performance of the composite cement, while no reduction was observed for the 7-µm CPC-Mont loaded cement formulation. Although CPC release substantially decreased during the 7-day period assessed, 5- and 7.5-wt% CPC-Mont loaded composite cement inhibited biofilm formation for 30 days. SIGNIFICANCE: Loading composite cement with CPC-Mont with a median diameter of 7 µm at concentrations of 5-7.5 wt% was effective in achieving continuous anti-biofilm activity, while maintaining mechanical strength and bonding performance.

Modulation of acoustic navigation behaviour by spatial learning in the echolocating bat Rhinolophus ferrumequinum nippon.

Using echolocation, bats receive acoustic information on their surroundings, which is assumed to help them sophisticatedly navigate complex environments. In this study, to understand spatial learning and acoustic sensing in bats, we investigated how flight and echolocation control changed in Rhinolophus ferrumequinum nippon as they learnt about their surroundings in an obstacle course that they flew through repeatedly. In these experiments, two testing environments (acoustically permeable and acoustically reflective) were prepared using chains and acrylic boards as obstacles to evaluate the interactive effects of spatial learning and flight environments. We found that bats reduced the meandering width of their flights and pulse emissions, and also seemed to reduce their shifts in pulse direction as they learnt more about their environments in both conditions. Throughout all our experiments, the bats with slower flight speeds tended to emit more pulses, which suggests that the number of pulse emissions reflects the echolocation tactics of each bat. The maximum flight speed was especially increased in the acoustically permeable condition, with frequent emissions of multiple pulses (≧triplets) in the early stages of flight, suggesting that bats adjust their flight plan based on how much of their surroundings they are able to sense in advance.

A case of intrathyroid parathyroid tumor that was difficult to diagnose by ultrasonography.

BACKGROUND: With advances in diagnostic imaging such as ultrasonography (US), computed tomography (CT), and 99mTc-MIBI-sestamibi (MIBI) scintigraphy, localized diagnosis of hyperparathyroidism (pHPT) has become possible with considerable accuracy. However, even with the use of these imaging techniques, since intrathyroid parathyroid tumors exist as a mass within the thyroid, it is often difficult to distinguish from thyroid masses. Although there have been various reports on US images of intraparathyroid tumors, we experienced a case with US images that were distinct from previous reports. Herein we present a case of an intrathyroid parathyroid adenoma (IPA) that was difficult to diagnose, with a main focus on US images. CASE PRESENTATION: A 53-year-old man with a diagnosis of hyperparathyroidism was referred to our department in December 2018. Ultrasonography revealed a tumor that was located in the inferior pole of the right lobe of the thyroid gland and no parathyroid mass was observed. The tumor had an irregular round shape and showed heterogeneous hyperechogenicity with a defined margin, but within it, there were a few irregular and hypoechogenic area with unclear margins, while the tumor had a mosaic appearance at first glance. Although 99mTc-MIBI scintigraphy showed accumulation at the same location in delayed phase, it was difficult to determine the presence of a parathyroid tumor on the image. The patient underwent an operation on April 2019 and the tumor could not be identified on both naked eye and palpation. We used US intraoperatively to define the location and resected the tumor. A parathyroid adenoma was diagnosed by frozen section and the final diagnosis was an intrathyroid parathyroid adenoma. CONCLUSION: We experienced an IPA presenting an US image that was atypical and has previously not been reported. IPA has no established US image to confirm the diagnosis and even with the use of other imaging techniques, a definitive diagnosis often cannot be established. Thus, our recommendation based on the current situation is that operation with intraoperative diagnosis using frozen section should be conducted if hypercalcemia and high I-PTH are observed and when localization sites in MIBI and US coincide.

Vertebrates originally possess four functional subtypes of G protein-coupled melatonin receptor.

Melatonin receptors (MTNRs) belonging to the G protein-coupled receptor family are considered to consist of three subtypes in vertebrates: MTNR1a, MTNR1b and MTNR1c. Additionally, MTNR1a-like genes have been identified in teleostean species as a fish-specific subtype of MTNR1a. However, similar molecules to this MTNR1a-like gene can be found in some reptiles upon searching the DNA database. We hypothesized that a vertebrate can essentially have four functional subtypes of MTNR as ohnologs. Thus, in the present study we examined the molecular phylogeny, expression patterns and pharmacological profile(s) using the teleost medaka (Oryzias latipes). The four conserved subtypes of MTNR (MTNR1a, MTNR1b, MTNR1c and MTNR1a-like) in vertebrates were classified based on synteny and phylogenetic analysis. The fourth MTNR, termed MTNR1a-like, could be classified as MTNR1d. It was observed by using RT-qPCR that expression patterns differed amongst these subtypes. Moreover, mtnr1a, mtnr1c and mtnr1a-like/mtnr1d expression was elevated during short days compared to long days in diencephalons. All the subtypes were activated by melatonin and transduced signals into the Gi pathway, to perform a cAMP-responsive reporter gene assay. It was shown that MTNR originally consisted of four subtypes: MTNR1a, MTNR1b, MTNR1c and MTNR1d. These subtypes were functional, at least in fish, although some organisms, including mammals, have lost one or two subtypes.

Selective Inhibition of ß-Catenin/Co-Activator Cyclic AMP Response Element-Binding Protein-Dependent Signaling Prevents the Emergence of Hapten-Induced Atopic Dermatitis-Like Dermatitis.

BACKGROUND: The canonical Wnt/ß-catenin signaling pathway is a fundamental regulatory system involved in various biological events. ICG-001 selectively blocks the interaction of ß-catenin with its transcriptional co-activator cyclic AMP response element-binding protein (CBP). Recent studies have provided convincing evidence of the inhibitory effects of ICG-001 on Wnt-driven disease models, such as organ fibrosis, cancer, acute lymphoblastic leukemia, and asthma. However, the effects of ICG-001 in atopic dermatitis (AD) have not been investigated. OBJECTIVE: To investigate whether ß-catenin/CBP-dependent signaling was contributed in the pathogenesis of AD and ICG-001 could be a therapeutic agent for AD. METHODS: We examined the effects of ICG-001 in an AD-like murine model generated by repeated topical application of the hapten, oxazolone (Ox). ICG-001 or vehicle alone was injected intraperitoneally every day during the development of AD-like dermatitis arising from once-daily Ox treatment. RESULTS: Ox-induced AD-like dermatitis characterized by increases in transepidermal water loss, epidermal thickness, dermal thickness accompanied by increased myofibroblast and mast cell counts, and serum levels of thymic stromal lymphopoietin and thymus and activation-regulated chemokine, and decreases in stratum corneum hydration, were virtually normalized by the treatment with ICG-001. Elevated serum levels of periostin tended to be downregulated, without statistical significance. CONCLUSION: These results suggest that ß-catenin/CBP-dependent signaling might be involved in the pathogenesis of AD and could be a therapeutic target.

[A Case of Laparoscopic Gastrojejunostomy for Duodenal Obstruction Caused by Unresectable Locally Advanced Pancreatic Cancer].

The patient was an 85-year-old man who received chemotherapy with gemcitabine for 2 years 9 months under the diagnosis of unresectable locally advanced pancreatic body and tail cancer. He visited our hospital because of anorexia, upper abdominal fullness, and vomiting. A CT scan showed severe stenosis in the third portion of the duodenum, which was associated with the direct invasion of the advanced pancreatic cancer. Upper gastrointestinal fiberscopy revealed a severe duodenal obstruction; however, pancreatic cancer exposure within the duodenal mucosa was not observed. As the stenosis of the duodenum was relatively smooth because of the cancer invasion into only the submucosa, deviation of the metallic stent was possible, so we performed laparoscopic gastrojejunostomy. We started the surgery with 5-port settings. A slit was made in the gastric body by using ENDO-GIA®, and bypass surgery with a Roux-en-Y anastomosis was performed. The postoperative course was good, and oral intake resumed on the third postoperative day. Thereafter, he could leave the hospital with good progress and received systemic chemotherapy using gemcitabine. In the present case, an extramural gastrointestinal stenosis without cancer that was not exposed in the gastrointestinal mucosa was poorly fixed with gastrointestinal metallic stents and use of a deviating metallic stent was reported, so we chose laparoscopic gastrojejunostomy. In addition, after undergoing laparoscopic surgery, which is a minimally invasive treatment, he recovered quickly and shifted early to systemic chemotherapy. Herein, the usefulness of laparoscopic gastrojejunostomy for extramural stenosis is reported with a review of related literature.

Effect of starting oral intake on weekends on the clinical course of patients with aspiration pneumonia.

PURPOSE: The aim of this study was to investigate whether the day of starting oral intake affects the clinical course of patients with aspiration pneumonia. RESULTS: We conducted a retrospective cohort study of 392 patients who were hospitalized for aspiration pneumonia but tolerated oral intake. Patients were divided into two groups according to the day of starting oral intake: Monday to Friday (midweek group) and Saturday or Sunday (weekend group). Underlying diseases, severity of pneumonia, time to oral intake, hospital duration, discontinuation of oral intake, and death during hospitalization were compared between the groups. Multivariate analysis was performed using hospital duration and discontinuation of oral intake due to aspiration as the dependent variables. RESULTS: The cohort comprised 244 men and 148 women with a mean age of 79.3 ± 13.1 years. The weekend (n = 98) and midweek (n = 294) groups exhibited similar age, sex, and underlying diseases. There were no significant differences in pneumonia-related factors, such as CURB-65 score, A-DROP score, extent of shadow on chest radiograph, incidence of bacteremia, and ventilator use. The weekend group exhibited a significantly shorter time to oral intake and hospital duration, as well as a significantly lower incidence of discontinuation of oral intake than the midweek group. Multivariate analysis revealed that starting oral intake on the weekend was independently associated with a lower incidence of discontinuation of oral intake due to aspiration. CONCLUSION: The weekend group exhibited a shorter total hospital duration and a lower incidence of discontinuation of oral intake due to aspiration.

A fourth subtype of retinoic acid receptor-related orphan receptors is activated by oxidized all-trans retinoic acid in medaka (Oryzias latipes).

BACKGROUND: The three known subtypes of the retinoic acid receptor-related orphan receptor (ROR) have been implicated in the control of immunity, brain function, and circadian rhythm in mammals. Here, we demonstrate by phylogenetic analysis that there were originally four subtypes of RORs in vertebrates. One of the novel ror paralogs, rord1 (rorca in the Ensembl database), is conserved among teleosts, but absent in mammals. Using medaka (Oryzias latipes) as a model teleost, we evaluated the expression pattern of this gene, its transactivational properties for endogenic chemicals, and its ability to activate the promoters of putative target genes. RESULTS: In eyes, the transcript of rord1 was expressed at higher levels during the day than at night. Interestingly, cholesterol derivatives, which are well-known ligands for mammalian RORs, did not efficiently promote transcriptional activity via RORd1. Thus we sought to identify the ligands that regulate the transcriptional activity of RORd1 using a luciferase reporter cell-based screening system. Using this system, we identified two metabolites of all-trans retinoic acid (ATRA), 4OH-ATRA and 4-keto ATRA, as potential ligands of RORd1. Moreover, RORd1 activated the promoter of cyp26a1 in a 4OH-ATRA -dependent manner. CONCLUSIONS: A novel ror subtype, rord has two paralogs, rord1 and rord2, in teleost. Rord1 mRNA is highly abundant in the eyes of medaka during light periods, suggesting that rord1 expression is involved in the regulation of circadian rhythm. We identified two ATRA metabolites, 4OH-ATRA and 4 K-ATRA, as endogenous candidate ligands of RORd1. We also show that 4-oxygenated ATRA metabolites have the potential to activate cyp26a1, the metabolic enzyme of ATRA. Our results support the notion that RORd1 is involved in the metabolism of ATRA in medaka.

Effects of Isolation by Continental Islands in the Seto Inland Sea, Japan, on Genetic Diversity of the Large Japanese Field Mouse, Apodemus speciosus (Rodentia: Muridae), Inferred from the Mitochondrial Dloop Region.

To study the effects of post-glacial isolation by islands on population genetic diversity and differentiation of the large Japanese field mouse, Apodemus speciosus, we examined partial nucleotide sequences of the mitochondrial Dloop region (ca. 300 bp) in 231 individuals collected from islands in the Seto Inland Sea and adjacent regions on Honshu and Shikoku Islands in the western part of the Japanese archipelago. Molecular phylogenetic and network analyses showed that haplotypes in each island tended to form monophyletic groups, while those in Honshu and Shikoku (the major Japanese islands) showed scattered relationships and were connected with island haplotypes. These observations suggest that a set of Honshu and Shikoku haplotypes became the ancestral lineages of the island population. No gene flow was detected among island populations, indicating that independent evolution occurred on each island, without the influence of human activities, since the establishment of the islands in the Holocene. Population genetic diversities on each island were lower than those on Honshu and Shikoku. Comparison between genetic diversity and island area size showed positive correlations and supported the suggestion that genetic drift is a major factor that shaped the current haplotype constitution of the islands in the Seto Inland Sea.

Factors involved in the discontinuation of oral intake in elderly patients with recurrent aspiration pneumonia: a multicenter study.

PURPOSE: To assess the factors involved in oral intake discontinuation in elderly patients with recurrent aspiration pneumonia. PATIENTS AND METHODS: This study included patients with pneumonia who were treated at Jichi Medical University Hospital between 2007 and 2013, at Toyooka Public Hospital between 2011 and 2013 and at Yuzawa Community Medical Center between 2010 and 2012. We consecutively enrolled patients with aspiration pneumonia. The primary study point was oral intake discontinuation after the initiation of oral intake during hospitalization in cases of recurrent aspiration. Various parameters were recorded at admission, at the initiation of intake, and during hospitalization; these parameters were statistically evaluated. RESULTS: A total of 390 patients were assigned to either a "no reaspiration of intake" group (n=310) or a "reaspiration of intake" group (n=80), depending on whether intake was discontinued owing to aspiration during hospitalization. At admission, the following items significantly differed between the groups: level of consciousness, respiratory rate, oxygen saturation, CURB-65 score, extent of infiltration/opacity on chest radiography, albumin levels, blood urea nitrogen levels, and application of swallowing function assessment. At the initiation of intake, level of consciousness, pulse rate, and albumin levels significantly differed between the groups. The following items did not significantly differ between groups: systolic blood pressure, pulse rate, C-reactive protein, bacteremia, use of ventilator at admission, oxygen administration, respiratory rate, and systolic blood pressure at initiation of intake. Multivariate analysis revealed that application of swallowing function assessment, level of consciousness at the initiation of intake, and extent of infiltration/opacity on chest radiography were significant predictive variables for discontinuation of intake. CONCLUSION: A low level of consciousness at the initiation of intake and a greater extent of infiltration/opacity on chest radiography and the application of a swallowing function are important factors. These factors may be helpful to determine a suitable timing for resumption of oral intake.

Differential Changes in Neuronal Excitability in the Spinal Dorsal Horn After Spinal Nerve Ligation in Rats.

Previous studies demonstrated that peripheral nerve injury induced excessive neuronal response and glial activation in the spinal cord dorsal horn, and such change has been proposed to reflect the development and maintenance of neuropathic pain states. The aim of this study was to examine neuronal excitability and glial activation in the spinal dorsal horn after peripheral nerve injury. We examined noxious heat stimulation-induced c-Fos protein-like immunoreactivity (Fos-LI) neuron profiles in fourth-to-sixth lumbar (L4-L6) level spinal dorsal horn neurons after fifth lumbar spinal nerve ligation (L5 SNL). Immunofluorescence labeling of OX-42 and GFAP was also performed in histological sections of the spinal cord. A significant increase in the number of Fos-LI neuron profiles in the spinal dorsal horn at the L4 level was found at 3 days after SNL, but returned to a level similar to that in sham-operated controls by 14 days after injury. As expected, a decrease in the number of Fos-LI neuron profiles in the spinal dorsal horn at the L5 level was found at 3 days after SNL. However, these profiles had reappeared in large numbers by 14 and 21 days after injury. Immunofluorescence labeling of OX-42 and GFAP indicated sequential activation of microglia and astrocytes in the spinal dorsal horn. We conclude that nerve injury causes differential changes in neuronal excitability in the spinal dorsal horn, which may coincide with glial activation. These changes may play a substantial role in the pathogenesis of neuropathic pain after peripheral nerve injury.

Boron Accelerates Cultured Osteoblastic Cell Activity through Calcium Flux.

A low concentration of boron (B) accelerates the proliferation and differentiation of mammalian osteoblasts. The aim of this study was to investigate the effects of 0.1 mM of B on the membrane function of osteoblastic cells in vitro. Genes involved in cell activity were investigated using gene expression microarray analyses. The Ca2+ influx and efflux were evaluated to demonstrate the activation of L-type Ca2+ channel for the Ca2+ influx, and that of Na+/K+-ATPase for the Ca2+ efflux. A real-time PCR analysis revealed that the messenger RNA (mRNA) expression of four mineralization-related genes was clearly increased after 3 days of culture with a B-supplemented culture medium. Using microarray analyses, five genes involved in cell proliferation and differentiation were upregulated compared to the control group. Regarding the Ca2+ influx, in the nifedipine-pretreated group, the relative fluorescence intensity for 1 min after adding B solution did not increase compared with that for 1 min before addition. In the control group, the relative fluorescence intensity was significantly increased compared with the experimental group (P < 0.05). Regarding the Ca2+ efflux, in the experimental group cultured in 0.1 mM of B-supplemented medium, the relative fluorescence intensity for 10 min after ouabain treatment revealed a significantly lower slope value compared with the control group (P < 0.01). This is the first study to demonstrate the acceleration of Ca2+ flux by B supplementation in osteoblastic cells. Cell membrane stability is related to the mechanism by which a very low concentration of B promotes the proliferation and differentiation of mammalian osteoblastic cells in vitro.

Activated microglia contribute to convergent nociceptive inputs to spinal dorsal horn neurons and the development of neuropathic pain.

The activation of microglia in the spinal dorsal horn following peripheral nerve injury has been reported previously, and this change has been proposed to contribute to the development of a neuropathic pain state. We recently demonstrated that peripheral nerve injury activated convergent nociceptive inputs to spinal dorsal horn neurons. The present study was designed to further examine the role of microglia in the activation of convergent nociceptive inputs as well as development of a neuropathic pain state after peripheral nerve injury. Tibial nerve injury initially induced hyposensitivity at 3 days post-injury, and this was followed by hypersensitivity to tactile and thermal stimuli at 14 days. The intraperitoneal administration of minocycline (30 mg/kg), an inhibitor of microglial activation, for 8 days starting on the day of surgery prevented increases in OX-42 immunofluorescence labeling in the spinal dorsal horn and the development of tactile and thermal hypersensitivity at 14 days post-injury. The same minocycline treatment (day 0-7) also reduced the nerve injury-induced convergence of nociceptive inputs to spinal dorsal horn neurons, as revealed by double immunofluorescence labeling for c-Fos induced by noxious heat stimulation of the hindpaw and phosphorylated extracellular signal-regulated kinase induced by electrical stimulation of the injured tibial nerve. However, the administration of minocycline for 8 days starting 7 days after surgery did not prevent nerve injury-induced microglial activation, convergent nociceptive inputs, or tactile and thermal hypersensitivity. These results suggest that microglial activation in the early stage following peripheral nerve injury plays an important role in the anomalous convergence of nociceptive signals to spinal dorsal horn neurons and the development of neuropathic pain.

Peripheral nerve injury activates convergent nociceptive input to dorsal horn neurons from neighboring intact nerve.

Previous studies demonstrated that peripheral nerve injury induced excessive nociceptive response of spinal cord dorsal horn neurons and such change has been proposed to reflect the development of neuropathic pain state. The aim of this study was to examine the spinal dorsal horn for convergence of nociceptive input to second-order neurons deafferented by peripheral nerve injury. Double immunofluorescence labeling for c-Fos and phosphorylated extracellular signal-regulated kinase (p-ERK) was performed to detect convergent synaptic input to spinal dorsal horn neurons after the saphenous nerve injury. c-Fos expression and the phosphorylation of ERK were induced by noxious heat stimulation of the hindpaw and by electrical stimulation of the injured or uninjured saphenous nerve, respectively. Within the central terminal field of the saphenous nerve, the number of c-Fos protein-like immunoreactive (c-Fos-IR) cell profiles was significantly decreased at 3 days and returned to the control level by 14 days after the injury. p-ERK immunoreactive (p-ERK-IR) cell profiles were distributed in the central terminal field of the saphenous nerve, and the topographic distribution pattern and number of such p-ERK-IR cell profiles remained unchanged after the nerve injury. The time course of changes in the number of double-labeled cell profiles was similar to that of c-Fos-IR cell profiles after the injury. These results indicate that convergent primary nociceptive input through neighboring intact nerves contributes to increased responsiveness of spinal dorsal horn nociceptive neurons.