Effects of different exercise intensities or durations on salivary IgA secretion

PURPOSE

This study aimed to examine changes in salivary immunoglobulin A (s-IgA) secretion at different intensities or durations of acute exercise.

METHODS

Twelve healthy untrained young males were included in randomized crossover trials in Experiment 1 (cycling exercise for 30 min at a work rate equivalent to 35%, 55%, and 75% maximal oxygen uptake [ V ˙ O2max]) and Experiment 2 (cycling exercise at 55% V ˙ O2max intensity for 30, 60, and 90 min). Saliva samples were collected at baseline, immediately after, and 60 min after each exercise.

RESULTS

Experiment 1: The percentage change in the s-IgA secretion rate in the 75% V ˙ O2max trial was significantly lower than that in the 55% V ˙ O2max trial immediately after exercise (- 45.7%). The percentage change in the salivary concentration of cortisol, an s-IgA regulating factor, immediately after exercise significantly increased compared to that at baseline in the 75% V ˙ O2max trial (+ 107.6%). A significant negative correlation was observed between the percentage changes in saliva flow rate and salivary cortisol concentration (r = - 0.52, P < 0.01). Experiment 2: The percentage change in the s-IgA secretion rate in the 90-min trial was significantly lower than that in the 30-min trial immediately after exercise (-37.0%). However, the percentage change in salivary cortisol concentration remained the same.

CONCLUSION

Our findings suggest that a reduction in s-IgA secretion is induced by exercise intensity of greater than or equal to 75% V ˙ O2max for 30 min or exercise duration of greater than or equal to 90 min at 55% V ˙ O2max in healthy untrained young men.

Cancer Screening Abstinence Rates and Rationales Among Regular Outpatients at a Rural Hospital in Japan: A Cross-Sectional Study

Purpose

This study aimed to investigate cancer screening rates and the reasons for not undergoing screening among patients who regularly visited the Sanmu Medical Center.

Patients and Methods

This prospective observational study recruited patients aged ≥40 years with regular clinic visits to Sanmu Medical Center during October 2019. We conducted a self-administered survey to determine the patient's sex and whether they underwent cancer screening in 2019, and if not, the reason for the same. The primary outcome measure was the percentage of people who did not undergo cancer screening.

Results

A total of 198 responses (108 male respondents) were obtained. Among them, 189 were valid responses (valid response rate 94.5%). One hundred and twenty-nine patients (68.2%, 76 male) had not undergone screening. The most common reasons provided were "I have regular regular clinic visits and do not think they are necessary" (N = 65, 50.3%), "I underwent a gastroscopy within 2 years, a colorectal camera examination within a few years, and a chest radiography within a year" (42.5%), and "I have a separate complete medical checkup" (N = 15, 11.6%). Of the 65 patients who responded that their cancer screenings were unnecessary, 42 patients (64.6%) had not undergone a gastroscopy within 2 years, a colorectal camera examination within a few years, or a chest radiography or examination within a year.

Conclusion

Roughly half of the respondents who did not undergo cancer screening elected to abstain because they believed that regular hospital visits were sufficient. Encouraging patients who regularly visit medical institutions to receive cancer screening is therefore necessary.

Ergogenic Effects of Very Low to Moderate Doses of Caffeine on Vertical Jump Performance

Although the ergogenic effects of 3-6 mg/kg caffeine are widely accepted, the efficacy of low doses of caffeine has been discussed. However, it is unclear whether the ergogenic effects of caffeine on jump performance are dose responsive in a wide range of doses. This study aimed to examine the effect of very low (1 mg/kg) to moderate doses of caffeine, including commonly utilized ergogenic doses (i.e., 3 and 6 mg/kg), on vertical jump performance. A total of 32 well-trained collegiate sprinters and jumpers performed countermovement jumps and squat jumps three times each in a double-blind, counterbalanced, randomized, crossover design. Participants ingested a placebo or 1, 3, or 6 mg/kg caffeine 60 min before jumping. Compared with the placebo, 6 mg/kg caffeine significantly enhanced countermovement jump (p < .001) and squat jump (p = .012) heights; furthermore, 1 and 3 mg/kg of caffeine also significantly increased countermovement jump height (1 mg/kg: p = .002, 3 mg/kg: p < .001) but not squat jump height (1 mg/kg: p = .436, 3 mg/kg: p = .054). There were no significant differences among all caffeine doses in both jumps (all p > .05). In conclusion, even at a dose as low as 1 mg/kg, caffeine improved vertical jump performance in a dose-independent manner. This study provides new insight into the applicability and feasibility of 1 mg/kg caffeine as a safe and effective ergogenic strategy for jump performance.

Dioscorea esculenta Intake with Resistance Training Improves Muscle Quantity and Quality in Healthy Middle-Aged and Older Adults: A Randomized Controlled Trial

Resistance training and Dioscorea esculenta intake have a positive effect on muscle. Therefore, we aimed to determine whether 12-week Dioscorea esculenta intake combined with resistance exercise more effectively improves muscle quantity, quality, and cardiometabolic parameters in healthy middle-aged and older adults. This study is a double-blind trial with 66 volunteers (21 males/45 females; age 53 ± 5 years; body weight 61 ± 11 kg; BMI 24 ± 4 kg) who were randomly divided into four groups: sedentary-control with placebo (Sed and PL) or Dioscorea (Sed and Dio) and resistance training with placebo (RT and PL) or Dioscorea (RT and Dio). Resistance training sessions using elastic bands were performed 3 days/week for a 12-week period. Dioscorea esculenta tablets were ingested at 2000 mg/day once per day. The RT and Dio group showed greater improvements in the femoris muscle's thickness, echo intensity for the rectus femoris (index of muscle quality), and the five times sit-to-stand test compared to that of the Sed and PL group; the echo intensity in the RT and Dio group further improved compared to those in the Sed and Dio, and RT and PL groups (p < 0.05). The circulating levels of C1q (a potential biomarker of muscle fibrosis) in the RT and Dio group were significantly lower than those in the Sed and PL, and Sed and Dio groups (p < 0.05). Chronic Dioscorea esculenta intake combined with low-intensity resistance exercise may more effectively improve muscle quantity and quality indices in healthy middle-aged and older adults.

Operation at 1 MHz of 1.7-cycle multiple plate compression at 35-W average output power

We generate 1.7-cycle and 35-µJ pulses at a 1-MHz repetition rate by using two-stage multiple plate continuum compression of Yb-laser pulses with 80-W average input power. By adjusting the plate positions with careful consideration of the thermal lensing effect due to the high average power, we compress the output pulse with a 184-fs initial duration to 5.7 fs by using only group-delay-dispersion compensation. This pulse achieves a sufficient beam quality (M² < 1.5) reaching a focused intensity over 10¹⁴ W/cm² and a high spatial-spectral homogeneity (98%). Our study holds promise for a MHz-isolated-attosecond-pulse source for advanced attosecond spectroscopic and imaging technologies with unprecedentedly high signal-to-noise ratios.

Acute Effect of Caffeine Supplementation on 100-m Sprint Running Performance: A Field Test

PURPOSE

No study has assessed the acute effect of caffeine supplementation on 100-m sprint running in athletics and caffeine's net ergogenicity on 100-m sprint running remains unclear. We investigated the acute effects of caffeine supplementation on 100-m sprint running performance in a field test.

METHODS

Thirteen male collegiate sprinters were subjected to 100-m sprint running time trials (TT) after the ingestion of 6 mg·kg -1 body weight caffeine or placebo supplementation in a double-blind, counterbalanced, randomized, and crossover design. Sprint velocity was measured with a laser system, and sprint time was calculated from the data in which the effects of environmental factors that would act as confounding factors on sprint time during TT were eliminated.

RESULTS

The corrected 100-m sprint time was significantly shortened by 0.14 s with caffeine supplementation compared with placebo (placebo: 11.40 ± 0.39 s, caffeine: 11.26 ± 0.33 s; P = 0.007, g = -0.33). The corrected sprint time up to 60 m during TT was also significantly shorter with caffeine supplementation than with placebo ( P = 0.002). Furthermore, the mean sprint velocity for splits of 0-10 and 10-20 m was significantly increased by caffeine supplementation (all P < 0.05).

CONCLUSIONS

Acute caffeine supplementation enhanced the corrected 100-m sprint time by improving the sprint performance in the first 60 m after more explosive acceleration in the early stage of the acceleration phase. Thus, for the first time, we directly demonstrated caffeine's ergogenicity on 100-m sprint performance in athletics.

Associations of time to return to performance following acute posterior thigh injuries with running biomechanics, hamstring function, and structure in collegiate sprinters: A prospective cohort design

BACKGROUND

The time to return to sport from acute hamstring strain injuries is associated with several functional and structural impairments. However, not all previous studies assessed the preinjury level before acute hamstring strain injuries directly. The purpose of this study was to examine the associations of the time to return to performance following acute hamstring strain injuries with deficits in running biomechanics, hamstring function and structure in collegiate sprinters by a prospective study.

METHODS

Using a prospective cohort design, 72 participants were recruited from a collegiate track and field team. At the preinjury assessment, a 60-m running-specific test, passive straight leg raise test and isometric knee flexion strength test were assessed at the beginning of the competitive season for three consecutive years (2017-2019). Afterwards, postinjury examinations were performed only in sprinters with acute hamstring strain injuries.

FINDINGS

Twelve sprinters strained their hamstring muscle (incidence rate of hamstring strain injuries: 16.7%); the majority (n = 10) were classified as grades 0-2. The running speed deficit of the running-specific test was associated with the time to return to performance as well as the passive straight leg raise test deficit. In the running-specific test, lower-limb kinetic deficits were more strongly associated with the time to return to performance compared to lower-limb kinematic deficits.

INTERPRETATION

A running-specific test may be considered one of the most convenient and valid tests for assessing rehabilitation progress after acute hamstring strain injuries.

Effect of Ankle Motion and Tensile Stress at the Achilles Tendon on the Contact Pressure Between the Achilles Tendon and the Calcaneus

Impingement between the Achilles tendon and the posterosuperior prominence of the calcaneus is considered to be a cause of insertional Achilles tendinopathy. The corresponding treatment intends to reduce tensile stress from calf muscles and avoid hyper-dorsiflexion of the ankle joint for decreasing the contact pressure; however, no study has reported on whether these treatments can decrease impingement. Thus, this study investigated the hypothesis that the tensile stress of the Achilles tendon and ankle motion affect the contact pressure between the Achilles tendon and the posterosuperior prominence of the calcaneus. Six fresh-frozen cadaveric lower leg specimens were procured. Each specimen was set to a custom foot-loading frame and loaded with a ground reaction force of 40 N and a tensile load of 70 N along the Achilles tendon. The contact pressure between the Achilles tendon and the posterosuperior prominence of the calcaneus was measured using a miniature pressure sensor under different tensile loadings of the Achilles tendon at the neutral ankle position. Similarly, the contact pressures during the ankle motion from a neutral position to maximum dorsiflexion were measured. The tensile load of the Achilles tendon and ankle motion affected the contact pressure between the Achilles tendon and the posterosuperior prominence of the calcaneus. The contact pressure increased with tensile load or ankle dorsiflexion. Conditions with increasing the tensile load of the Achilles tendon or under ankle dorsiflexion increase the contact pressure between the Achilles tendon and the posterosuperior prominence of the calcaneus.

Relationship between vancomycin-associated nephrotoxicity and the number of combined nephrotoxic agents

Vancomycin is associated with nephrotoxicity; however, the influence of the number of combined nephrotoxic agents on the incidence of vancomycin nephrotoxicity has not been clarified. We investigated patient backgrounds in 148 inpatients who received vancomycin treatment. The patients were divided into nephrotoxicity (n=35) and non-nephrotoxicity (n=113) groups. A comparison of the patient backgrounds in the two groups revealed significant differences in weight, changes in serum creatinine before vancomycin administration, blood urea nitrogen to serum creatinine ratio, length of vancomycin therapy, vancomycin trough concentration, and number of combined nephrotoxic agents. Multiple logistic regression analysis using these six factors as autonomous variables showed that the highest vancomycin trough concentration (odds ratio, 1.080; 95% confidence interval, 1.030-1.140; p = 0.003) and the number of combined nephrotoxic agents (odds ratio, 1.590; 95% confidence interval, 1.120-2.260; p = 0.010) were significantly related to nephrotoxicity.

A false-pouch closure technique with an intact superior peroneal retinaculum for recurrent dislocation of the peroneal tendon

Purpose

To evaluate the usefulness of the false-pouch closure technique with an intact superior peroneal retinaculum (SPR).

Methods

From 2016 to 2020, 30 patients with recurrent dislocation of the peroneal tendon were treated with the current procedure. Clinical outcomes, including the time to resume running, the rate and time to return to sports, and the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hind Foot score, were evaluated preoperatively and at the last follow-up.

Results

The rate of return to the pre-injury level of sports activity was 93.3%, and the mean duration to return to running and sports was 8.0 ± 2.8 weeks (range: 3–12 weeks) and 14.4 ± 3.2 weeks (range: 10–24 weeks), respectively. The mean preoperative AOFAS score was 79.7 ± 9.6 points (range: 41–90), which improved significantly to 98.9 ± 3.2 (87–100) postoperatively (p < 0.01).

Conclusion

The false-pouch closure technique with suture tape and anchors had a reliable clinical outcome and can enable the early return of patients to their sports activities.

Level of evidence

IV, Case series

Plasma brain-derived neurotrophic factor and dynamic cerebral autoregulation in acute response to glycemic control following breakfast in young men

We examined the acute impact of both low- and high-glycemic index (GI) breakfasts on plasma brain-derived neurotrophic factor (BDNF) and dynamic cerebral autoregulation (dCA) compared with breakfast omission. Ten healthy men (age 24 ± 1 yr) performed three trials in a randomized crossover order; omission and Low-GI (GI = 40) and High-GI (GI = 71) breakfast conditions. Middle cerebral artery velocity (transcranial Doppler ultrasonography) and arterial pressure (finger photoplethysmography) were continuously measured for 5 min before and 120 min following breakfast consumption to determine dCA using transfer function analysis. After these measurements of dCA, venous blood samples for the assessment of plasma BDNF were obtained. Moreover, blood glucose was measured before breakfast and every 30 min thereafter. The area under the curve of 2 h postprandial blood glucose in the High-GI trial was higher than the Low-GI trial (P < 0.01). The GI of the breakfast did not affect BDNF. In addition, both very-low (VLF) and low-frequency (LF) transfer function phase or gains were not changed during the omission trial. In contrast, LF gain (High-GI P < 0.05) and normalized gain (Low-GI P < 0.05) were decreased by both GI trials, while a decrease in VLF phase was observed in only the High-GI trial (P < 0.05). These findings indicate that breakfast consumption augmented dCA in the LF range but High-GI breakfast attenuated cerebral blood flow regulation against slow change (i.e., the VLF range) in arterial pressure. Thus we propose that breakfast and glycemic control may be an important strategy to optimize cerebrovascular health.

The Effect of Leucine-Enriched Essential Amino Acid Supplementation on Anabolic and Catabolic Signaling in Human Skeletal Muscle after Acute Resistance Exercise: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Comparison Trial

Resistance exercise transiently activates anabolic and catabolic systems in skeletal muscle. Leucine-enriched essential amino acids (LEAAs) are reported to stimulate the muscle anabolic response at a lower dose than whey protein. However, little is known regarding the effect of LEAA supplementation on the resistance exercise-induced responses of the anabolic and catabolic systems. Here, we conducted a randomized, double-blind, placebo-controlled, parallel-group comparison trial to investigate the effect of LEAA supplementation on mechanistic target of rapamycin complex 1 (mTORC1), the ubiquitin-proteasome system and inflammatory cytokines after a single bout of resistance exercise in young men. A total of 20 healthy young male subjects were supplemented with either 5 g of LEAA or placebo, and then they performed 10 reps in three sets of leg extensions and leg curls (70% one-repetition maximum). LEAA supplementation augmented the phosphorylation of mTOR^Ser2448 (+77.1%, p < 0.05), p70S6K^Thr389 (+1067.4%, p < 0.05), rpS6^Ser240/244 (+171.3%, p < 0.05) and 4EBP1^Thr37/46 (+33.4%, p < 0.05) after resistance exercise. However, LEAA supplementation did not change the response of the ubiquitinated proteins, MuRF-1 and Atrogin-1 expression. Additionally, the mRNA expression of IL-1β and IL-6 did not change. These data indicated that LEAA supplementation augments the effect of resistance exercise by enhancing mTORC1 signal activation after exercise.

Effect of Mixed Meal and Leucine Intake on Plasma Amino Acid Concentrations in Young Men

Dietary protein intake is critical for the maintenance of skeletal muscle mass. Plasma amino acid concentrations increase with protein intake and increases in muscle protein synthesis are dependent on leucine concentrations. We aimed to investigate the effect of a mixed meal and free amino acids intake on plasma leucine concentrations. In this randomized crossover study, 10 healthy young men (age 25 ± 1 years, height 1.73 ± 0.02 m, weight 65.8 ± 1.5 kg) underwent tests under different conditions—intake of 2 g of leucine (LEU), intake of a mixed meal (protein 27.5 g, including 2.15 g of leucine, protein: fat: carbohydrate ratio—22:25:53) only (MEAL), intake of 2 g of leucine immediately after a mixed meal (MEAL-LEU) and intake of 2 g of leucine 180 min after a mixed meal (MEAL-LEU180). Blood samples were collected within 420 min (240 min for LEU only) after intake and changes in amino acid concentrations were evaluated. Although the maximum plasma leucine concentration increased to 442 ± 24 µM for LEU, it was lower at 347 ± 16 µM (p < 0.05 vs. LEU) for MEAL-LEU, 205 ± 8 µM (p < 0.05 vs. LEU) for MEAL. The maximum plasma leucine concentration for MEAL-LEU180 increased to 481 ± 27 µM and compared to LEU there was no significant difference (p > 0.1). The observation that rapid elevations in plasma leucine concentrations are suppressed when leucine is ingested at the same time as a meal suggests that the timing of its intake must be considered to maximize the anabolic response.

Polarization-Resolved Study of High Harmonics from Bulk Semiconductors

The polarization property of high harmonics from gallium selenide is investigated using linearly polarized midinfrared laser pulses. With a high electric field, the perpendicular polarization component of the odd harmonics emerges, which is not present with a low electric field and cannot be explained by the perturbative nonlinear optics. A two-dimensional single-band model is developed to show that the anisotropic curvature of an energy band of solids, which is pronounced in an outer part of the Brillouin zone, induces the generation of the perpendicular odd harmonics. This model is validated by three-dimensional quantum mechanical simulations, which reproduce the orientation dependence of the odd-order harmonics. The quantum mechanical simulations also reveal that the odd- and even-order harmonics are produced predominantly by the intraband current and interband polarization, respectively. These experimental and theoretical demonstrations clearly show a strong link between the band structure of a solid and the polarization property of the odd-order harmonics.

Subcultured Odontogenic Epithelial Cells in Combination with Dental Mesenchymal Cells Produce Enamel–Dentin-Like Complex Structures

We showed in a previous study that odontogenic epithelial cells can be selectively cultured from the enamel organ in serum-free medium and expanded using feeder layers of 3T3-J2 cells. The subcultured odontogenic epithelial cells retain the capacity for ameloblast-related gene expression, as shown by semiquantitative RT-PCR. The purpose of the present study was to evaluate the potential of subcultured odontogenic epithelial cells to form tooth structures in cell–polymer constructs maintained in vivo. Enamel organs from 6-month-old porcine third molars were dissociated into single odontogenic epithelial cells and subcultured on feeder layers of 3T3-J2 cells. Amelogenin expression was detected in the subcultured odontogenic epithelial cells by immunostaining and Western blotting. The subcultured odontogenic epithelial cells were seeded onto collagen sponge scaffolds in combination with fresh dental mesenchymal cells, and transplanted into athymic rats. After 4 weeks, enamel–dentin-like complex structures were present in the implanted constructs. These results show that our culture system produced differentiating ameloblast-like cells that were able to secrete amelogenin proteins and form enamel-like tissues in vivo. This application of the subculturing technique provides a foundation for further tooth-tissue engineering and for improving our understanding of ameloblast biology.

Perfusion MR Imaging Using a 3D Pulsed Continuous Arterial Spin-Labeling Method for Acute Cerebral Infarction Classified as Branch Atheromatous Disease Involving the Lenticulostriate Artery Territory

BACKGROUND AND PURPOSE

Branch atheromatous disease is a stroke subtype considered a risk factor for early neurologic deterioration. Meanwhile, crossed cerebellar diaschisis is thought to be influenced by the degree and location of supratentorial perfusion abnormalities and is associated with the clinical outcome in the case of an ischemic stroke. In this article, our aim was to clarify the utility of using a whole-brain 3D pulsed continuous arterial spin-labeling method as an imaging biomarker for predicting neurologic severity in branch atheromatous disease.

MATERIALS AND METHODS

Twenty-three patients with branch atheromatous disease in the lenticulostriate artery territory were enrolled. All patients underwent MR imaging, including DWI, 3D-TOF-MRA, and 3D-arterial spin-labeling. We measured the asymmetry index of CBF in the affected area (branch atheromatous disease), the asymmetry index of the contralateral cerebellar hemisphere (crossed cerebellar diaschisis), and the DWI infarct volume in the lenticulostriate artery territory. We also compared each parameter with the initial NIHSS score with the Pearson correlation coefficient.

RESULTS

Among the 23 patients, we found no correlation between NIHSS score and the asymmetry index of CBF in the affected area (branch atheromatous disease) (r = -0.027, P = .724), whereas the asymmetry index of the contralateral cerebellar hemisphere (crossed cerebellar diaschisis) and DWI infarct volumes were significantly correlated with NIHSS score (r = 0.515, P = .012; r = 0.664, P = .001, respectively).

CONCLUSIONS

In patients with branch atheromatous disease, 3D-arterial spin-labeling can detect crossed cerebellar diaschisis, which is correlated with the degree of neurologic severity.

Tissue-specific expression and silencing phenotypes of mitochondrial phosphate carrier paralogues in several insect species

The mitochondrial phosphate carrier gene (PiC) encodes a membrane protein that mediates the supply of inorganic phosphate from the cytosol into the mitochondrial matrix. This substrate-specific transport system plays an important role in efficient ATP synthesis. Mammals appear to have only one PiC with two alternative splicing variants whose functional differences remain unclear. The present study is the first to characterize the multiple genes that encode PiC in insects. Bombyx mori was found to have two PiC paralogues, one ubiquitous and one testis-specific, the latter seeming to be present only in Lepidoptera. Drosophila melanogaster was found to harbour two PiC paralogues, whereas Liriomyza chinensis, another dipteran, has three PiC paralogues. Two PiCs were found to be present in Plautia stali, and silencing either of these genes affected the normal development of P. stali nymphs, although their expression patterns differed amongst tissues. Schistocerca gregaria and Locusta migratoria have two PiC each, with different expression patterns. Tribolium castaneum was found to have only one PiC, which appears to play an essential role in larval development. Thus, although the inorganic phosphate transport system appears to be conserved across eukaryotes, PiC has become specialized in the different tissues of different insect species.

Attosecond dynamical Franz-Keldysh effect in polycrystalline diamond

Short, intense laser pulses can be used to access the transition regime between classical and quantum optical responses in dielectrics. In this regime, the relative roles of inter- and intraband light-driven electronic transitions remain uncertain. We applied attosecond transient absorption spectroscopy to investigate the interaction between polycrystalline diamond and a few-femtosecond infrared pulse with intensity below the critical intensity of optical breakdown. Ab initio time-dependent density functional theory calculations, in tandem with a two-band parabolic model, accounted for the experimental results in the framework of the dynamical Franz-Keldysh effect and identified infrared induction of intraband currents as the main physical mechanism responsible for the observations.

Effective Bone Engineering with Periosteum-derived Cells

Bone augmentation via tissue engineering has generated significant interest. We hypothesized that periosteum-derived cells could be used in place of bone marrow stromal cells (which are widely used) in bone engineering, but the differences in osteogenic potential between these 2 cell types are unclear. Here, we compared the osteogenic potential of these cells, and investigated the optimal osteoinductive conditions for periosteum-derived cells. Both cell types were induced, via bFGF and BMP-2, to differentiate into osteoblasts. Periosteal cells proliferated faster than marrow stromal cells, and osteogenic markers indicated that bone marrow stromal cells were more osteogenic than periosteal cells. However, pre-treatment with bFGF made periosteal cells more sensitive to BMP-2 and more osteogenic. Transplants of periosteal cells treated with BMP-2 after pre-treatment with bFGF formed more new bone than did marrow stromal cells. Analysis of these data suggests that combined treatment with bFGF and BMP-2 can make periosteum a highly useful source of bone regeneration.

Arthroscopic Resection of Symptomatic Ossicle of the Medial Malleolus: A Case Report

An ossicle around the medial malleolus is difficult to differentiate from an unfused ossification center, an avulsion fracture, and os subtibiale. Misdiagnosis can lead to inappropriate or unnecessary treatments. We describe a patient with a symptomatic ossicle of the medial malleolus in the left ankle that prevented participation in sports activities because of medial ankle pain. Plain radiography and computed tomography revealed a small ossicle associated with the anterior colliculus of the medial malleolus. Conservative treatment failed, and the patient underwent ankle arthroscopy. Instability of the ossicle was identified after the hypertrophic inflammatory synovium had been debrided. The ossicle was resected in a step-by-step manner with an arthroscopic shaver and grasper through the anteromedial accessary portal. The deltoid ligament sustained minimal damage after resection. The patient fully recovered and was able to return to sports activities 3 months after surgery. Arthroscopic resection of the ossicle at the medial malleolus requires no additional treatments of the deltoid ligament, effectively relieves symptoms, and enables the patient to return to full preinjury activities.

Analysis of trabecular bone microstructure in osteoporotic femoral heads in human patients: in vivo study using multidetector row computed tomography

BACKGROUND

Lag screw position is very important in the treatment of intertrochanteric femoral fracture to prevent complications such as screw cut-out. Current studies recommend central or inferior placement of the lag screw on the anteroposterior radiograph, and central placement on the lateral radiographs. These reports are based on radiographic evaluation, but few studies have investigated the importance of bone quality at the site of lag screw placement. In this study, we used multidetector row computed tomography (MDCT) to perform in vivo evaluation of the bone microstructure of the femoral head in patients with intertrochanteric femoral fractures.

METHODS

This study was approved by the Ethics Committee of Okanami General Hospital. MDCT images were obtained in our hospital from ten patients who had sustained intertrochanteric femoral fracture. Patients who needed computed tomography to confirm fracture morphology were included. We defined six areas as regions of interest (ROI): ROI 1-3 were defined as the femoral head apex area, and ROI 4-6 were defined as the femoral neck area. Trabecular microstructure parameters, including mean bone volume to total volume (BV/TV), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), and structure model index (SMI), were evaluated with bone analysis software (TRI/3D-BON). Statistical analyses were performed using EZR software; each parameter among the ROIs was statistically evaluated by analysis of variance (ANOVA) and Tukey's test. Statistical significance was established at p < 0.05.

RESULTS

In the apical area, all parameters indicated that ROI 1 (superior) had the highest bone quality and ROI 2 (central) was higher in bone quality than ROI 3 (inferior). In the femoral neck, all parameters indicated that bone quality was significantly greater in ROI 6 (inferior) than ROI 5 (central).

DISCUSSION AND CONCLUSIONS

We could evaluate bone quality with clinical MDCT in vivo. Bone quality in the central area of the femoral head apical was greater than in the inferior area, and bone quality in the inferior area of the femoral neck was greater than in the central area. Recognizing which area of femoral head has greater bone quality may lead to a better clinical result in treating intertrochanteric femoral fracture.

Healing of localized gingival recessions treated with a coronally advanced flap alone or combined with an enamel matrix derivative and a porcine acellular dermal matrix: a preclinical study

OBJECTIVE

This study aimed to evaluate the effects of a porcine acellular dermal matrix (PADM) with or without an enamel matrix derivative (EMD) on gingival recession defects treated with a coronally advanced flap (CAF) in dogs.

MATERIALS AND METHODS

Miller class II gingival recession defects (5 mm wide and 7 mm deep) were surgically created on the labial side of bilateral maxillary canines in 12 dogs. After 8 weeks of plaque accumulation, the 24 chronic defects were randomly assigned to one of the following 4 treatments: CAF, CAF with PADM (CAF/PADM), CAF with EMD (CAF/EMD), and CAF with EMD and PADM (CAF/EMD/PADM). The animals were sacrificed 10 weeks after surgery for histologic evaluation.

RESULTS

In all groups, root coverage was obtained to a varying degree. PADM was well incorporated in gingival connective tissue in the CAF/PADM and in the CAF/EMD/PADM groups. The height of newly formed bone was significantly greater in the CAF/EMD/PADM group than in the CAF and CAF/PADM groups. New cementum with periodontal ligament-like tissue was predominantly found in the CAF/EMD and CAF/EMD/PADM groups. The CAF/EMD/PADM group showed the greatest amount of new cementum among the groups examined, although the difference was not statistically significant.

CONCLUSION

Within the limitations of the present study, it can be concluded that CAF/EMD/PADM treatment may promote periodontal regeneration in gingival recession defects.

CLINICAL RELEVANCE

The present results suggest that the combination of EMD and PADM in conjunction with CAF may represent a promising approach for treating single Miller class II gingival recessions.

Asbestos textile production linked to malignant peritoneal and pleural mesothelioma in women: Analysis of 28 cases in Southeast China

BACKGROUND

Chrysotile had been used in asbestos textile workshops in Southeast China but a clear relation to mesothelioma is lacking.

METHODS

All patients diagnosed with mesothelioma from 2003 to 2010 at Yuyao People's Hospital were re-evaluated by multiple expert pathologists with immunohistochemistry and asbestos exposure data were collected.

RESULTS

Of 43 patients with a mesothelioma diagnosis, 19 peritoneal and nine pleural cases were finally diagnosed as mesothelioma. All were females, and the mean age of the patients with peritoneal or pleural mesothelioma was 52.4 and 58.2 years, respectively. All these cases had a history of domestic or occupational exposure to chrysotile. Two-thirds of the patients were from two adjoining towns with multiple small asbestos textile workshops. Contamination of tremolite was estimated to be less than 0.3%.

CONCLUSIONS

This is a report of mesothelioma in women exposed to chrysotile asbestos at home and at work, with an over-representation of peritoneal mesothelioma.

The molecular composition of the extracellular matrix of the human iliolumbar ligament

BACKGROUND CONTEXT

The human iliolumbar ligament connects the transverse process of L5 to the iliac crest and contributes to lumbosacral stability and has been associated with low back pain. However, different opinions exist regarding the functional relevance of the ligament.

PURPOSE

In the present study, we analyze the regional molecular composition of the ligament extracellular matrix.

STUDY DESIGN

Special attention is given to the attachment sites, to determine whether the ligament is subjected to a certain mechanical environment.

METHODS

Iliolumbar ligament samples, extending from one enthesis to the other, were removed from 11 cadavers and fixed in methanol. Cryosections were immunolabeled with a panel of antibodies directed against collagens, glycosaminoglycans, proteoglycans, matrix proteins, and neurofilament.

RESULTS

The mid-substance of the ligament labeled for all the molecules normally found in dense fibrous connective tissue including types I, III, and VI collagen, versican, dermatan -, chondroitin 4 -, and keratan sulfate. However, both entheses were fibrocartilaginous and labeled for type II collagen, aggrecan, and chondroitin 6- sulfate. A common feature was fat between the fiber bundles near the entheses. Occasionally this fat contained nerve fibers.

CONCLUSIONS

The existence of fibrocartilaginous entheses suggests that the insertion sites of the ligament are subject to both tensile and compressive loading-probably because of insertional angle changes between ligament and bone during loading. Our findings support the suggestion that the iliolumbar ligament might play an important role in the stabilization of the lumbosacral junction.

Significant relationship between the extent of pleural plaques and pulmonary asbestos body concentration in lung cancer patients with occupational asbestos exposure

BACKGROUND

The aim of this study was to elucidate whether there is a relationship between the extent of pleural plaques and pulmonary asbestos body concentration (PABC).

METHODS

The subjects were 207 lung cancer patients with occupational asbestos exposure. We determined the plaque extent by findings on chest images using our own criteria. PABCs were measured in resected or autopsy lung specimens.

RESULTS

There was a significant relationship between plaque extent and PABC. Seventy-five percent of the patients determined to have extensive plaques based on our criteria had a PABC of ≥5,000 asbestos bodies per gram of dry lung tissue, which is one of the certification criteria of lung cancer caused by asbestos for workers' compensation in Japan.

CONCLUSIONS

In lung cancer patients, the plaque extent had a significant positive relationship with the PABC. The plaque extent would be useful as a proxy for PABC for lung cancer compensation purposes.

Adaptive changes of extracellular amino acid concentrations in mouse dorsal striatum by 4-AP-induced cortical seizures

The striatum is a major target of cerebral cortical output. The cortico-striatal projection has been well described, however, the neurochemical changes that occur in the striatum after prolonged cortical hyperactivation remain to be investigated. In this study, extracellular levels of glutamate, GABA, and alanine levels were measured in the dorsal striatum using microdialysis in anesthetized mice at resting condition and during 4-aminopyridine (4-AP)-induced cortical seizures. After topical application of 4-AP on the primary motor cortex that induced cortical seizures, the extracellular level of striatal GABA increased by 40% in 60 min. By contrast, the extracellular level of striatal glutamate decreased by 20%. Moreover, the surface amounts of striatal glutamate/aspartate transporter (GLAST) and glutamate transporter 1 (GLT-1), the major astrocytic high-affinity glutamate transporters, tended to increase by cortical seizures in 60 min, suggesting a recruitment of the glutamate transporters from internal stores. 4-AP also resulted in a steady increase of alanine levels which are thought to reflect glutamate and pyruvate metabolism in neurons and astrocytes. These observations possibly delineate adaptive changes of striatal metabolism by severe cortical seizures.

Effect of interleukin-1beta and dehydroepiandrosterone on the expression of lumican and fibromodulin in fibroblast-like synovial cells of the human temporomandibular joint

Several epidemiological studies have reported that temporomandibular disorders (TMDs) are more prevalent in women than in men. It has recently been proposed that sex hormones such as estrogen, testosterone and dehydroepiandrosterone (DHEA) are involved with the pathogenesis of TMDs. Although studies have investigated the relationship between estrogen and testosterone and the restoration of TMDs, the relationship between DHEA and TMDs is unknown. The synovial tissue of the temporomandibular joint (TMJ) is made up of connective tissue with an extracellular matrix (ECM) composed of collagen and proteoglycan. One proteoglycan family, comprised of small leucine-rich repeat proteoglycans (SLRPs), was found to be involved in collagen fibril formation and interaction. In recent years, the participation of SLRPs such as lumican and fibromodulin in the internal derangement of TMJ has been suggested. Although these SLRPs may contribute to the restoration of the synovium, their effect is still unclear. The purpose of this study was to investigate the effect of DHEA, a sex hormone, on the expression of lumican and fibromodulin in human temporomandibular specimens and in cultured human TMJ fibroblast-like synovial cells in the presence or absence of the pro-inflammatory cytokine interleukin-1beta (IL-1beta). In the in vivo study, both normal and osteoarthritic (OA) human temporomandibular synovial tissues were immunohistochemically examined. In the in vitro study, five fibroblast-like synoviocyte (FLS) cell lines were established from human TMJ synovial tissue of patients with osteoarthritis. The subcultured cells were then incubated for 3, 6, 12 or 24 h with/without IL-1beta (1 ng/mL) in the presence or absence of DHEA (10 μM). The gene expression of lumican and fibromodulin was examined using the real-time polymerase chain reaction (PCR) and their protein expression was examined using immunofluorescent staining. We demonstrated that the expression of lumican differs from that of fibromodulin in synovial tissue and furthermore, that IL-1beta induced a significant increase in lumican mRNA and immunofluorescent staining in FLS compared to cells without IL-1beta. DHEA plus IL-1beta induced a significant increase in fibromodulin, but not in lumican mRNA, compared to DHEA alone, IL-1beta alone and in the absence of DHEA and IL-1beta. In immunofluorescent staining, weaker fibromodulin staining of FLS cells was observed in cells cultured in the absence of both DHEA and IL-1beta compared to fibromodulin staining of cells cultured with DHEA alone, with DHEA plus IL-1beta, or with IL-1beta alone. These results indicate that DHEA may have a protective effect on synovial tissue in TMJ by enhancing fibromodulin formation after IL-1beta induced inflammation. DHEA enhancement of fibromodulin expression may also exert a protective effect against the hyperplasia of fibrous tissue that TGF-beta1 induces. In addition lumican and fibromodulin are differentially expressed under different cell stimulation conditions and lumican and fibromodulin may promote regeneration of the TMJ after degeneration and deformation induced by IL-1beta.

Inhibition of fibrous adhesion formation in the temporomandibular joint of tenascin-C knockout mice

Tenascin-C (TNC) is a large hexameric extracellular matrix glycoprotein that is expressed in developing organs and tumors. It has been reported that TNC is expressed in inflamed synovial membranes and deformed discs of temporomandibular joint (TMJ) disorder. However, the role of TNC in TMJ is not fully known. In this study, the role of TNC in fibrous adhesion formation of TMJ was examined using TNC knockout (TNCKO) mice. Hypermobility was produced by excessive mouth opening method on the TMJ of both wild-type (WT) and TNCKO mice. TMJ wound healing was compared histologically, and the expression of TNC, fibronectin (FN) and α-smooth muscle actin (α-SMA) in the wounded TMJ was examined by immunohistochemical and immunoblot analyses. Based on histologic analysis, fibrous adhesions were observed in the TMJ of both TNCKO and wild-type (WT) mice after excessive mouth opening. However, fibrous adhesion formation in TNCKO mice occurred later than in WT mice. TNC was expressed in the wounded TMJ disc and mandibular fossa. Although FN and α-SMA expression in the TMJ of TNCKO and WT mice was up-regulated after excessive mouth opening, FN and α-SMA protein levels were higher in WT mice at the same time points. In the wounded TMJ, TNC appears to enhance the expression of FN and α-SMA, and a lack of TNC may reduce fibrous adhesion formation in the TMJ. TNC plays an important role in TMJ wound healing, especially for wounds generated by mechanical stress.

Differences in elements between intact and disrupted human ligamenta capitum femorum

To compare the element compositions between intact (i.e., intact throughout its length) and disrupted (i.e., ligament no longer attached to the attachment) ligaments, the contents of elements in the human ligamenta capitum femorum (LCF) were analyzed by inductively coupled plasma-atomic emission spectrometry. Histological and immunohistological assessments were also performed in both groups. The subjects were 8 men and 32 women. Trace element analyses showed that the sulfur and iron contents were significantly greater in the intact group than in the disrupted group, while the phosphorus and magnesium contents were significantly smaller in the intact group than in the disrupted group. The calcium and zinc contents were smaller in the intact group than in the disrupted group, with no significant differences. Histologically, there were fibrocartilage cells and extracellular matrix metachromasia in ligaments of the intact group. In contrast, fibrocartilage cells disappeared, and fat cells appeared instead of collagen fibrils in ligaments of the disrupted group. The LCFs of the intact group were immunohistologically positive for all components examined including collagens, glycosaminoglycans, and proteoglycans. The increase in sulfur suggested the presence of high glycosaminoglycan levels associated with fibrocartilaginous metaplasia in the ligament by compressive force. The reduction in iron may show a decreased number of blood vessels in the synovium after ligament disruption. The increases in phosphorus, magnesium, and calcium are indicative of degenerative changes including calcification and ossification. We conclude that differences in the contents of elements between intact and disrupted LCFs indicate degenerative alterations to the ligament structure after disruption.

Depletion of gangliosides enhances cartilage degradation in mice

OBJECTIVE

Glycosphingolipids (GSLs) are ubiquitous membrane components that play a functional role in maintaining chondrocyte homeostasis. We investigated the potential role of gangliosides, one of the major components of GSLs, in osteoarthritis (OA) pathogenesis.

DESIGN

Both age-associated and instability-induced OA models were generated using GM3 synthase knockout (GM3S(-/-)) mice. A cartilage degradation model and transiently GM3S-transfected chondrocytes were analyzed to evaluate the function of gangliosides in OA development. The amount of each series of GSLs in chondrocytes after IL-1α stimulation was profiled using mass spectrometry (MS).

RESULTS

OA changes in GM3S(-/-) mice were dramatically enhanced with aging compared to those in wild-type (WT) mice. GM3S(-/-) mice showed more severe instability-induced pathologic OA in vivo. Ganglioside deficiency also led to the induction of matrix metalloproteinase (MMP)-13 and ADAMTS-5 secretion and chondrocyte apoptosis in vitro. In contrast, transient GM3S transfection of chondrocytes suppressed MMP-13 and ADAMTS-5 expression after interleukin (IL)-1α stimulation. GSL profiling revealed the presence of abundant gangliosides in chondrocytes after IL-1α stimulation.

CONCLUSION

Gangliosides play a critical role in OA pathogenesis by regulating the expression of MMP-13 and ADAMTS-5 and chondrocyte apoptosis. Based on the obtained results, we propose that gangliosides are potential target molecules for the development of novel OA treatments.

Regional differences in elements of human peroneus longus tendons

Many studies have been performed on the structure, molecular composition, and biochemical properties of tendons. However, comparatively little research has been conducted on the content of various trace elements within tendons. Six elements were analyzed in four regions of the peroneus longus tendon: the tensional part of the tendon immediately proximal to the lateral malleolus (region A), the compressive region of the tendon in contact with the lateral malleolus (region B), the compressive region of the tendon in contact with the deep surface of the cuboid (region C), and the tensional part of the tendon between the cuboid and first metatarsal, to which the tendon is attached (region D). Regions B and C are wraparound regions. The calcium content was higher in region C (2.10 ± 0.93 mg/g) than in both regions A (1.25 ± 0.51 mg/g) and D (1.43 ± 0.41 mg/g) (p < 0.05), indicating that it is likely related to regional differences in cartilage degeneration. The phosphorus content was also higher in region C, possibly because of low alkaline phosphatase activity in this region. The sulfur content was higher in the wraparound regions (region B: 0.98 ± 0.09 mg/g, region C: 1.24 ± 0.19 mg/g) than in both regions A (0.83 ± 0.11 mg/g) and D (0.83 ± 0.1 mg/g) (p < 0.01); sulfur content is thought to be influenced by tendon-bone compression. Finally, the magnesium content in the wraparound regions was also higher, which is probably related to a higher level of fibrocartilage. No significant relationships were found with regard to zinc or iron. Overall, the findings of the present study indicate that element contents are related to function and anatomical differences in tendons, and that they may even vary within the same tendon.

Evaluation of Parkinson disease and Alzheimer disease with the use of neuromelanin MR imaging and (123)I-metaiodobenzylguanidine scintigraphy

BACKGROUND AND PURPOSE

Progressive changes in the substantia nigra pars compacta and locus ceruleus of patients with Parkinson disease and Alzheimer disease visualized by neuromelanin MRI and cardiac postganglionic sympathetic nerve function on (123)I-metaiodobenzylguanidine scintigraphy have not been fully evaluated. We compared the diagnostic value of these modalities among patients with early Parkinson disease, late Parkinson disease, and Alzheimer disease.

MATERIALS AND METHODS

We compared contrast ratios of signal intensity in medial and lateral regions of the substantia nigra pars compacta and locus ceruleus with those of the tegmentum of the midbrain and the pons, respectively, by use of neuromelanin MRI in patients with early Parkinson disease (n = 13), late Parkinson disease (n = 31), Alzheimer disease (n = 6), and age-matched healthy control subjects (n = 20). We calculated heart-to-mediastinum ratios on (123)I-metaiodobenzylguanidine scintigrams after setting regions of interest on the left cardiac ventricle and upper mediastinum.

RESULTS

The signal intensity of the lateral substantia nigra pars compacta on neuromelanin MRI was significantly reduced in early and late Parkinson disease, and that of the medial substantia nigra pars compacta was gradually and stage-dependently reduced in Parkinson disease. The signal intensity of the locus ceruleus was obviously reduced in late Parkinson disease. Signal reduction was not significant in the substantia nigra pars compacta and locus ceruleus of patients with Alzheimer disease. The heart-to-mediastinum ratio on (123)I-metaiodobenzylguanidine scintigrams was stage-dependently reduced in Parkinson disease and normal in Alzheimer disease. The signal intensity ratios in substantia nigra pars compacta and locus ceruleus on neuromelanin MRI positively correlated with the heart-to-mediastinum ratio on (123)I-metaiodobenzylguanidine scintigrams.

CONCLUSIONS

Both neuromelanin MRI and (123)I-metaiodobenzylguanidine scintigraphy can help to evaluate disease progression in Parkinson disease and are useful for differentiating Parkinson disease from Alzheimer disease.

Parenchymal hypointense foci associated with developmental venous anomalies: evaluation by phase-sensitive MR Imaging at 3T

BACKGROUND AND PURPOSE

The risk of hemorrhage in the context of developmental venous anomaly is considered to be very low, but it has never been evaluated by susceptibility-weighted MR imaging at 3T. The goal of the present study was to evaluate the prevalence of hypointense foci (ie, microhemorrhage or cavernous malformation) associated with DVA on phase-sensitive MR imaging, on the basis of principles similar to those of susceptibility-weighted MR imaging, and to evaluate the relationship between the hypointense foci and several factors, such as white matter hyperintense lesions adjacent to DVA on T2-weighted imaging, DVA morphology, and clinical symptoms.

MATERIALS AND METHODS

This study retrospectively evaluated 61 lesions in 59 consecutive patients with DVA who underwent MR imaging including phase-sensitive MR imaging. Two neuroradiologists independently assessed for the presence of hypointense foci and other factors such as DVA location, depth, size, direction of draining vein on phase-sensitive MR imaging, and white matter hyperintense lesion on T2-weighted imaging. Clinical symptoms were also assessed.

RESULTS

Hypointense foci were observed in 62.3% (38/61) of lesions. White matter hyperintense lesion was more frequently observed in patients with hypointense foci (26/38) than in patients without hypointense foci (7/23) (P < .01). There was no significant association between hypointense foci and other factors.

CONCLUSIONS

Our results support the hypothesis that microhemorrhage or cavernous malformation can be related to venous congestion caused by abnormal venous drainage. We conclude that phase-sensitive MR imagingis useful for the detection of microhemorrhage or cavernous malformation in patients with DVA, especially when associated with white matter hyperintense lesion.