Na+/K+ ATPase α1 and β3 subunits are localized to the basolateral membrane of trophectoderm cells in human blastocysts

STUDY QUESTION

Is there a relation between specific Na+/K+ ATPase isoform expression and localization in human blastocysts and the developmental behavior of the embryo?

SUMMARY ANSWER

Na+/K+ ATPase α1, β1 and β3 are the main isoforms expressed in human blastocysts and no association was found between the expression level of their respective mRNAs and the rate of blastocyst expansion.

WHAT IS KNOWN ALREADY

In mouse embryos, Na+/K+ ATPase α1 and β1 are expressed in the basolateral membrane of trophectoderm (TE) cells and are believed to be involved in blastocoel formation (cavitation).

STUDY DESIGN, SIZE, DURATION

A total of 20 surplus embryos from 11 patients who underwent IVF and embryo transfer at a university hospital between 2009 and 2018 were analyzed.

PARTICIPANTS/MATERIALS, SETTING, METHODS

After freezing and thawing Day 5 human blastocysts, their developmental behavior was observed for 24 h using time-lapse imaging, and the expression of Na+/K+ ATPase isoforms was examined using quantitative RT-PCR (RT-qPCR). The expressed isoforms were then localized in blastocysts using fluorescent immunostaining.

MAIN RESULTS AND THE ROLE OF CHANCE

RT-qPCR results demonstrated the expression of Na+/K+ ATPase α1, β1 and β3 isoforms in human blastocysts. Isoforms α1 and β3 were localized to the basolateral membrane of TE cells, and β1 was localized between TE cells. A high level of β3 mRNA expression correlated with easier hatching (P = 0.0261).

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

The expression of mRNA and the localization of proteins of interest were verified, but we have not been able to perform functional analysis.

WIDER IMPLICATIONS OF THE FINDINGS

Of the various Na+/K+ ATPase isoforms, expression levels of the α1, β1 and β3 mRNAs were clearly higher than other isoforms in human blastocysts. Since α1 and β3 were localized to the basolateral membrane via fluorescent immunostaining, we believe that these subunits contribute to the dilation of the blastocoel. The β1 isoform is localized between TE cells and may be involved in tight junction formation, as previously reported in mouse embryos.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the JSPS KAKENHI (https://www.jsps.go.jp/english/index.html), grant number 17K11215. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The authors have no conflicts of interest.

Relationship between cardiac magnetic resonance derived extracellular volume fraction and myocardial strain in patients with non-ischemic dilated cardiomyopathy

Background

The feature tracking (FT) technique has been proposed as a robust method to evaluate the myocardial strain using conventional cine magnetic resonance imaging (MRI) of the left ventricle. Data is limited regarding the relationship between FT-derived myocardial strain and diffuse myocardial fibrosis evaluated by T1 mapping in patients with non-ischemic dilated cardiomyopathy (NIDCM).

Purpose

The aim of this study was to evaluate the correlation between extracellular volume (ECV) by T1 mapping and myocardial strain by FT in patients with NIDCM.

Methods

A total of sixty-four patients with NIDCM (62±12 years) and 15 controls (62±11 years) were studied. Using a 1.5T MR scanner, pre- and post- T1 mapping images of LV wall at mid-ventricular level was acquired to calculate ECV by modified Look-Locker inversion recovery (MOLLI) sequence. Radial strain (RS), circumferential strain (CS) and longitudinal strain (LS) was assessed by FT technique. ECV and myocardial strain were compared using a 6-segment model at mid-ventricular level.

Results

Compared to the controls, the NIDCM patients had a significantly higher ECV (0.30±0.02 vs. 0.24±0.01, p<0.001) and impaired myocardial strain (RS, 24.2±3.0 vs. 52.2±6.2, p<0.001; CS, −7.5±2.1 vs. −15.3±2.2, p<0.001; LS −10.4±3.5 vs. −20.2±4.7, p<0.001, respectively). Similar results were obtained when comparing all 6 myocardial segments (segment 7–12) (all p values <0.001). In a segment-based analysis, a significant positive correlation was found between the ECV and CS (r=0.26 to 0.41; all p values <0.05), a negative correlation was found between the ECV and RS (r=−0.31 to −0.41; all p values <0.05). In a patient-based analysis, there were significant positive correlations between the ECV and CS (r=0.45, p<0.001), ECV and LS from 2-chamber view (r=0.30, p=0.006), ECV and LS from 4-chamber view (r=0.37, p<0.001). There was a significant negative correlation between the ECV and RS (r=−0.43, p<0.001) (FIGURE)

Conclusions

In NIDCM patients, severity of myocardial fibrosis evaluated by T1 mapping is associated with impaired myocardial strain by FT technique.

Correlation between the ECV and strain

Funding Acknowledgement

Type of funding source: None

Extracellular volume fraction by T1 mapping predicts omprovement of left ventricular ejection fraction after catheter ablation in patients with non-ischemic cardiomyopathy and atrial fibrillation

Background

The Catheter Ablation versus Standard Conventional Therapy in Patients with Left Ventricular Dysfunction and Atrial Fibrillation (CASTLE-AF) trial has shown that the catheter ablation (CA) for atrial fibrillation (AF) significantly reduced the risk of death and hospitalization for heart failure in patients with non-ischemic dilated cardiomyopathy (NIDCM) and AF (N Engl J Med 2018; 378:417–27). In addition, the Catheter Ablation Versus Medical Rate Control in Atrial Fibrillation and Systolic Dysfunction (CAMERA-MRI) study demonstrated that the absence of myocardial fibrosis on late gadolinium enhanced (LGE) magnetic resonance imaging (MRI) is associated with improvement of left ventricular systolic function after CA in NIDCM patients with AF (J Am Coll Cardiol 2017; 70:1949–61). Extracellular volume fraction (ECV) by T1 mapping has emerges as a non-invasive mean to quantify diffuse myocardial fibrosis.

Purpose

The aim of this study was to compare the predictive value of LGE-MRI and ECV by T1 mapping for the prediction of improvement of LVEF after CA in NIDCM patients.

Methods

A total of twenty-eight patients with NIDCM and AF (age: 67±10 years; 25 (89%) male; LVEF: 34.1±8.8%) were studied. Using a 1.5T MR scanner and 32 channel cardiac coils, cine MRI, LGE-MRI, pre- and post- T1 mapping images of LV wall at mid-ventricular level (modified Look-Locker inversion recovery sequence) were acquired. Myocardial fibrosis on LGE was defined as area with >5SD signal intensity of normal myocardium. ECV from six segments of mid ventricular level were averaged for each patient. All patients underwent CA for AF, and the improvement of LVEF before and after CA were evaluated by echocardiography.

Results

All patients restored sinus rhythm after CA at the time of echocardiography. The mean LVEF was 34.1±8.8% before CA and 49.1±12.0% after CA (p<0.001), resulting an improvement of 15.0±11.8%. Significant correlation was found between improvements in LVEF and amount of fibrosis on LGE-MRI (r=−0.40, p=0.034), improvement of LVEF and ECV (r=−0.55, p=0.008). In the ROC analysis, ECV had a higher discriminative ability for the improvement of LVEF after CA compared with amount of fibrosis on LGE-MRI (AUC 0.885 vs 0.650) (Figure).

Conclusions

In NIDCM patients with AF, ECV by T1 mapping had better predictive ability for improvement of LVEF after CA in comparison to LGE-MRI.

ROC curves of ECV and LGE-MRI

Funding Acknowledgement

Type of funding source: None

Thermal conductivity evidence for a dx2-y2 pairing symmetry in the heavy-fermion CeIrIn5 superconductor

The phase diagram of the quasi-2D Ce(Ir,Rh)In5 system contains two distinct superconducting domes. By the thermal transport measurements in rotating magnetic fields H, we pinned down the superconducting gap structure of CeIrIn5 in the second dome, located distant from the first dome in proximity to an antiferromagnetic quantum critical point. Clear fourfold oscillation was observed when H is rotated within the ab plane, while no oscillation was observed within the bc plane. In sharp contrast to previous reports, our results are most consistent with dx2-y2 symmetry, implying that the superconductivity in the second phase is also mediated by antiferromagnetic spin fluctuations.

Exotic superconducting properties in the electron-hole-compensated heavy-fermion "Semimetal" URu2Si2

We show that the charge and thermal transport measurements on ultraclean crystals of URu2Si2 reveal a number of unprecedented superconducting properties. The uniqueness is best highlighted by the peculiar field dependence of thermal conductivity including the first-order transition at Hc2 with a reduction of entropy flow. This is a consequence of multiband superconductivity with compensated electronic structure in the hidden order state of this system. We provide strong evidence for a new type of unconventional superconductivity with two distinct gaps having different nodal topology.

Pathophysiological role of endothelin in ectopic ossification of human spinal ligaments induced by mechanical stress

Ossification of the posterior longitudinal ligament (OPLL) of the spine is characterized by progressive ectopic bone formation in the spinal ligament. To identify the genes related to ossification affected by mechanical stress during OPLL, analyses using cDNA microarray were carried out using cultured human spinal ligament cells that had been subjected to uniaxial cyclic stretching. Samples were obtained from a total of 14 patients: seven cervical or thoracic OPLL patients and seven control patients. Spinal ligament cells derived from tissues of OPLL (OPLL cells) and control (non-OPLL cells) patients were subjected to uniaxial sinusoidal cyclic stretching (0.5 Hz, 20% stretch) for various time periods (0-9 hours). cDNA microarrays revealed that ranges of distribution of both up- and downregulated genes evoked by cyclic stretching were significantly wider in OPLL cells than in non-OPLL cells. Increases in the mRNA expression of endothelin-1 (ET-1) as well as various marker genes related to ossification were also observed. mRNA expression of ET-1 and alkaline phosphatase was increased by mechanical stress in a time-dependent manner, while addition of ET-1 to static cultures of OPLL cells increased mRNA expression of alkaline phosphatase in a dose-dependent manner. During 9 hours of cyclic stretching, ET-1 release increased to about sixfold the amount observed in nonstretched cells. In non-OPLL cells, neither cyclic stretching nor ET-1 induced any increase in alkaline phosphatase expression. These results suggest that mechanical stress promotes the progression of ossification in OPLL cells through autocrine and/or paracrine mechanisms of ET-1.

Effects of in ovo exposure to imazalil and atrazine on sexual differentiation in chick gonads

We examined the effects of atrazine and imazalil, 2 commonly used pesticides, on sexual differentiation in chickens. Atrazine and imazalil were injected into fertile eggs on d 0. At hatching, sex genotype and phenotype were determined. Gonads were stereomicroscopically and histologically observed. In ovo exposure of atrazine (0.01 to 3 mg/egg) did not influence hatchability, whereas imazalil exposure (2 mg/egg) inhibited hatchability. The sex genotype matched the sex phenotype in controls, atrazine, and imazalil-exposed groups. In control females, the right gonad was regressed at hatching. Regression of the right gonad, however, was inhibited following atrazine and imazalil exposure. In atrazine-exposed female chicks, the left gonads had normal ovary structures, and the remaining right gonads had ovary medulla-like structures. In imazalil-exposed females, some left gonads had an ovary medulla-like structure without the cortex as well as tubules, and the right gonad had testis-like structures. There was no change in male gonads at hatching following atrazine and imazalil exposure. Aromatase activity of the left gonad from female chicks was not changed by any concentration of atrazine exposure. These results suggest that atrazine and imazalil inhibit regression of the right gonad in female chicks, although it is not clear whether the remaining right gonad has aromatase activity. In ovo exposure to atrazine influences sexual differentiation of the ovary by different mechanisms from imazalil, possibly by the induction of aromatase in the right gonad, whereas it is confirmed that imazalil inhibits in vitro aromatase activity in the chick ovary. The results indicated that in ovo exposure to imazalil inhibits sexual differentiation of the ovary by inhibiting aromatase activity.

Magnetic resonance analysis of abnormal diaphragmatic motion in patients with emphysema

The purpose of this study was to quantitatively evaluate paradoxical diaphragmatic motion using magnetic resonance (MR) imaging. A total of 27 subjects were examined, including 12 normal young adults, six control individuals, and nine patients with emphysema. With subjects in the supine position, 30 sequential sagittal MR images of the entire right lung were obtained during tidal and deep slow breathing. Diaphragmatic movement between sequential images was estimated as the displacement area and the total diaphragmatic movement in a respiratory cycle was calculated. The paradoxical motion of the diaphragm, representing the inverted movement to increase or decrease lung area, since paradoxical movement ratio (Mpr=(total paradoxical diaphragmatic movement/total diaphragmatic movement)x100), was evaluated. In patients with emphysema, paradoxical diaphragmatic motion was observed on MR images during deep breathing. The mean Mpr in emphysematous patients during deep breathing was 10+/-4%, which was significantly higher than 0.5+/-0.2% in young adults (p<0.05), and 1.2+/-0.6% in aged-matched controls (p<0.05). The present results indicate that magnetic resonance images could be used to detect paradoxical diaphragmatic motion in patients with emphysema.

Screening for abdominal aortic aneurysms during a basic medical checkup in residents of a Japanese rural community

To determine the prevalence of abdominal aortic aneurysms (AAA) and the size distribution of the abdominal aortic diameter in the Japanese population, 1,591 residents of a farming community were screened by ultrasonography during the annual basic medical checkup arranged by the town. The mean diameter of the abdominal aorta was 17.2 +/- 2.2mm and four AAAs were found (0.3%), all in men aged 60 years or older, three of whom were hypertensive. The mean diameter of the common iliac artery was 10.2 +/- 5.1mm and five iliac arterial aneurysms were found (0.3%). One man had both aortic and iliac arterial aneurysms. The iliac arterial aneurysms were also found in men, four of whom were aged 60 years or older and had a smoking habit. We were able to keep the cost of screening low by combining the program with an annual basic medical checkup. These findings indicate that it is important to examine the iliac artery as well as the abdominal aorta because the incidence of aneurysm is similar in both. Screening for AAAs using ultrasonography is accurate enough to detect them before rupture, and can be effectively performed in men aged 60 years or older during their annual basic medical checkup.

Biomarker distribution after injection into the canine prostate: implications for gene therapy

OBJECTIVE

To evaluate the distribution of biomarkers after transrectal injection into the canine prostate and to report a method for enhancing the distribution of gene expression.

MATERIALS AND METHODS

Carbon black was first used to evaluate the histopathological distribution in canine prostate of single or multiple injections via the transurethral, transperineal and transrectal routes. The distribution of canarypox virus (ALVAC) vector-delivered gene expression was then compared using both fluid-phase injection techniques and delivery in a solid carrier composed of a gelatine sponge matrix.

RESULTS

After transurethral administration, carbon black was detected as scattered particles in ducts and acini, mostly in the periphery of the gland. Direct transrectal injection of carbon black resulted in a localized collection at the site of injection, with only a minimal peri-acinar distribution. Transrectal injection of the fluid-phase (virus suspended in diluent) ALVAC vector encoding the beta-galactosidase gene resulted in a similar distribution, with limited gene expression at the site of injection and in the needle track. Delivery of the same number of virus particles in the gelatine sponge matrix resulted in qualitatively greater gene expression.

CONCLUSIONS

Direct injection of the canine prostate with biomarkers, including viral vectors, in the fluid-phase results in very localized gene expression, while the distribution was more widespread after delivery in a gelatine sponge matrix.

Paradoxical motion of the hemidiaphragm in patients with emphysema

The authors evaluate paradoxical diaphragmatic motion using magnetic resonance (MR) imaging in patients with emphysema. The subjects were 12 healthy volunteers and 10 male patients with moderate to severe air flow obstruction. With subjects in the supine position, 30 sequential sagittal images of the bilateral lungs were obtained during quiet and forced breathing using a 1.5T MR unit with a body coil. The sequence was single shot fast spin echo (SSFSE) with half Fourier transformation. Subtraction images were made from the original images (by subtracting a given image from the preceding image), which visualized the chest wall motion as white or black bands on the edge of the lung fields. The authors evaluated both the original and subtraction images. MR imaging showed abnormal hemidiaphragmatic motion during forced breathing: the ventral portion of the hemidiaphragm moved downward while the dorsal part moved upward like a seesaw in 6 patients. MR images also revealed abnormal ribcage motion; the ventral ribcage moved anteriorly when the hemidiaphragm moved upward in 7 patients. No abnormal motion was observed in healthy volunteers. MR is a noninvasive and useful tool for evaluating the asynchronous respiratory motion in patients with emphysema.

MR in vivo imaging of oxygen suppression effect of soft contact lens on the human cornea

The O(2) suppression effect of a soft contact lens on the human cornea was measured using dynamic magnetic resonance imaging (MRI) of the anterior chamber transcorneally exposed to O(2). Dynamic T(1)-weighted fast spin echo imaging of anterior chambers (TR = 2 s, TE = 15 ms, 5-mm slice) was performed both before and during oxygen supply to a full goggle placed on the face of volunteers wearing a soft contact lens on one eye and nothing on the other eye as a control. Within 15 min after O(2) administration, significantly lower intensity changes were obtained in the anterior chambers of the eyes with the contact lens than in those of the eyes without one, suggesting that dynamic MRI of the anterior chamber transcorneally exposed to O(2) can be used to evaluate the O(2) suppression effect of a soft contact lens on the cornea.

MR findings of bowlegs in toddlers

BACKGROUND

Toddlers with severe physiologic tibial bowing are considered to be at risk for the development of Blount's disease. Objective. To correlate MR findings of the knee with the clinical outcome in toddlers with severe physiological tibial bowing.

MATERIALS AND METHODS

MR findings were evaluated in 22 affected legs of 14 children with severe tibial bowing (mean age 1.9 years). In 18 affected legs, MR findings were compared with the transition of the tibial metaphyseal-diaphyseal angle (MDA) and tibiofemoral angle (TFA) measured serially between 2 and 3 years of age.

RESULTS

MR findings of severe tibial bowing comprised undulation of the posteromedial physis of the tibia (3/22), signal alterations in the medial tibial metaphysis (10/22), T2 prolongation in the posteromedial tibial epiphyseal cartilage (14/22) and signal changes in the medial menisci (18/22). The decrease in the TFA was different in the legs with and without increased signal in the epiphyseal cartilage, and the decrease in the MDA was different in the legs with and without physeal undulation.

CONCLUSION

MR imaging findings can predict the retarded resolution of tibial bowing, which may be a risk factor for the development of Blount's disease.

Normal in-plane respiratory motion of the bilateral hemidiaphragms evaluated by sequentially subtracted fast magnetic resonance images

The purpose of this study was to demonstrate hemidiaphragmatic motion using magnetic resonance imaging. The subjects were 13 healthy, nonsmoking volunteers. The sequence consisted of a fast gradient-recalled echo for coronal images and a single-shot fast spin echo with half Fourier transformation for sagittal images. The coronal and sagittal acquisition times were 0.83 msec and 0.58 msec per image, respectively. Thirty sequential images were obtained during quiet, deep respiration. Two series of subtraction images were made from these original sequential images (a given image was subtracted from the preceding or the next image in the original series). Hemidiaphragmatic motion was visualized as white or black bands on subtraction images. In the coronal plane through the left ventricle, there was a difference in motion between the right and left hemidiaphragms in 10 subjects during tidal respiration and in 12 subjects during deep respiration. On the sagittal images, the dorsal part of the hemidiaphragm moved more rapidly during quiet, deep respiration, especially on the left side.

Variability of platyspondylic lethal chondrodysplasia: another case report

We report the radiological and histological findings of another case of platyspondylic lethal chondrodysplasia. The patient was a girl, who died of respiratory failure at 18 days of age. The radiological changes comprised moderate platyspondyly with ovoid-shaped vertebral bodies, broad and short ilia, rhizomelic shortening and mild bowing of the long bones (particularly of the humeri), relatively long short tubular bones, and retarded epiphyseal ossification and ragged metaphyses, which were most similar to those of a mild variant of this entity, the Luton type. However, the histological findings of cartilage, including hypercellularity of the reserve zone with round resting chondrocytes, relatively normal column formation of the proliferative and hypertrophic zones, and incorporation of hypertrophic cartilage with a columnar arrangement into metaphyseal bony trabeculae, resemble those of a severe variant of this entity, the Torrance type. Our observation provides an insight into the phenotypic variabilities of platyspondylic lethal chondrodysplasia.

Dynamic MRI of transcorneal dispersion of oxygen into the anterior chamber of human eye

To measure the transcorneal dispersion of oxygen into the anterior chamber, dynamic T1-weighted fast-spin-echo MRI (TR=2 seconds, TE=15 msec, 5-mm slice) of the human eye was performed both before and during oxygen supply to a full goggle placed on the face. During the course of the imaging, a significant increase in the signals in the anterior chamber occurred. This indicated that transcorneal dispersion of oxygen into the anterior chamber can be evaluated by this procedure, suggesting that this method may be useful for diagnosing dysfunction of the cornea or aqueous flow.

[Changes in acetylcholine level and its related enzyme activities in rat brain following focal ischemia]

At 1 to 4 weeks following middle cerebral artery occlusion in Wistar rats, levels of acetylcholine, which is neuro-transmitter, were measured. In the hippocampus, which plays an important role in memory, levels of acetylcholine in the ischemic group could not be detected the significant difference compared with those in the sham-operated group. But in the anterior cortex and the caudate-putamen, levels of acetylcholine in the ischemic group were recognized the significant difference compared with those in the sham operated group. Moreover activities of choline acetyltransferase, which is the synthetic enzyme of acetylcholine, and activities of acetylcholinesterase, which is the degradative enzyme of acetylcholine, were measured in the anterior cortex which was recognized decrease of the acetylcholine level and the hippocampus which could not be detected the difference of the acetylcholine level. Activities of both enzymes in the hippocampus could not be recognized the significant difference between the ischemic group and the normal group. But in the anterior cortex activities of both enzymes in the ischemic group were significantly decreased compared with those in the normal group. These results suggest that these decreases in the ischemic group were due to damage of injection of cholinergic neuron from Meynert nucleus (basal nucleus of Meynert) to anterior cortex.

Diffusion-weighted imaging of the human optic nerve: a new approach to evaluate optic neuritis in multiple sclerosis

The apparent diffusion coefficient (ADC) in the optic nerve was measured from diffusion-weighted magnetic resonance imaging using an intravoxel incoherent motion (IVIM) sequence. The subjects were seven normal volunteers and eight patients with multiple sclerosis (MS) with a total of four optic nerves with acute neuritis and nine nerves with chronic neuritis. The mean ADC (4.18 +/- 1.13 x 10(-3) mm2/s, n = 9) in the optic nerves with chronic neuritis was significantly higher than that in normal volunteers (1.56 +/- 0.675 x 10(-3) mm2/s, n = 14) and that in the nerves with acute neuritis (0.94 +/- 0.43 x 10(-3) mm2/s n = 4) (P < 0.001). The ADC is useful in assessing MS foci in the optic nerves.

In vitro cellular aging stimulates interleukin-1 beta production in stretched human periodontal-ligament-derived cells

Although the severity of periodontal disease is known to be affected by host age, the pathological role of aging in periodontal disease, and especially that attributable to trauma from occlusion, has not been well-characterized. Interleukin (IL)-1 beta is a key mediator involved in periodontal diseases, a potent stimulator of bone resorption. Furthermore, it is produced by human periodontal ligament (PDL) cells in response to mechanical stress. To investigate the age-related changes in the biosynthetic capacity of IL-1 beta in PDL cells, we examined the effects of in vitro cellular aging with mechanical stress on IL-1 beta protein and gene expression by human PDL cells. Human PDL cells (young = 5th or 6th passage; old = 18-20th passage) were cultured on flexible-bottomed culture plates, and the cells were deformed at 6 cycles per min at 2 steps of tension force for 1 to 5 days. We found a two-fold increase in IL-1 beta production by old PDL cells subjected to mechanical tension compared with that by young PDL cells, although the constitutive levels of IL-1 beta were similar in both the young and old PDL cells. This increase was tension-dependent. IL- 1 beta mRNA was also detected in both cell types under basal conditions, and its expression was further enhanced by application of mechanical tension by use of reverse-transcription-polymerase chain-reaction (RT-PCR) and in situ hybridization methods. The increase in signal rate was higher in the old cells than in the young cells. IL-1 beta-converting enzyme mRNA remained unchanged. It is possible that a large amount of IL- 1 beta produced by PDL cells from an aged host in response to mechanical force may be positively related to the acceleration of alveolar bone resorption.

Cephalometric analysis of masseter muscle and dentoskeletal morphology in dentate and edentulous humans

A study was done to clarify the attachment position of the superficial masseter muscle and its relationship with craniofacial morphology in dentate and edentulous subjects. Data were obtained from lateral cephalometric radiographs of a total of 39 cadavers in which the superficial masseter muscle had been defined with colloidal barium. Principal component analysis provided evidence that the lower masseter muscle width was associated with the size of the ramus, and related to the position of the anterior margin of the muscle. Linear discriminant function data suggested that ramus width, coronoid height and the distance between the anterior margin of the masseter muscle and the mandibular notch contributed most to the observed difference between dentate and edentulous subjects. The derived function correctly assigned 100% of dentate and 95% of edentulous subjects. The results of this study indicated that a reduction of masticatory function was associated with the position of the anterior border of the masseter muscle insertion and also with differences in ramus dimension, the most significant of which were differences in the coronoid process and gonial angle. In general, age was not a significant determinant of variation in superficial masseter muscle dimensions or orientation.

Microscopic intraosseous extension of osteosarcoma: assessment on dynamic contrast-enhanced MRI

OBJECTIVE

This study investigated whether dynamic MRI could determine microscopic intraosseous invasion in osteosarcoma.

PATIENTS

Six patients with osteosarcoma who underwent total resection of the tumor after chemotherapy were studied.

DESIGN

The steepest slope value of the time-intensity curve was calculated on the basis of the first-pass method on dynamic MRI performed after chemotherapy. Slope value modified log = [100.(SIb - SIa)/(Tb - Ta)/SIa], where SIa and SIb represent the signal intensity at time points Ta and Tb when the steepest slope started and ended, respectively. The slope value was correlated with the histological findings of the surgical specimens. The findings on conventional MRI were also reviewed.

RESULTS AND CONCLUSIONS

In five of six patients microscopic tumor invasion ranging from 1 to 3.5 cm in depth was pathologically proven. The slope value within the microscopic invasion (-0.052 +/- 0.267) was significantly greater than that of tumour-free marrow (-0.609 +/- 0.220) and less than that in areas showing macroscopic tumor invasion (0.595 +/- 0.483) (P < 0.001). Histological examination disclosed the dilatation of small vessels within the macroscopic and microscopic invasion. Findings on conventional MRI varied among patients; microscopic invasion was not detected in one, underestimated in two, and overestimated in two. It is concluded that calculation of the slope value on dynamic MRI can discriminate regions of microscopic invasion from tumor-free marrow in patients with osteosarcoma after chemotherapy.

Effect of tension-force on plasminogen activator activity from human periodontal ligament cells

The plasminogen activator (PA)-plasmin proteolytic system has recently received considerable attention because of its participation in a wide variety of biological activities and in pathological conditions involving tissue destruction. Excessive mechanical stress such as occlusal trauma is associated with alveolar bone loss in severe periodontitis. Therefore, mechanical stress may involve degradation of the extracellular matrix by occlusal trauma through activation of the PA-plasmin proteolytic system. We examined the effects of mechanical stress on PA activity, gene expressions of tissue type (t) PA, urokinase type (u) PA and PA inhibitor-1 (PAI-1) in human PDL cells. Human PDL cells were cultured on flexible-bottomed culture plates and placed on a Flexercell Strain Unit. The cells were flexed at 6 cycles (5 s strain, 5 s relaxation) at 9% and 18% elongation for 5 d. Application of tension-force induced significantly higher PA activity in stressed PDL cells than in non-stressed controls, and did so in a time- and magnitude-dependent manner (p < 0.001, ANOVA). Western-blot analysis revealed that the high level of activity was due to tPA and not uPA. Gene expression of tPA mRNA in stressed PDL cells, as examined by RT-PCR, increased on d 5. These findings suggest that tPA may be involved in periodontal metabolism in response to mechanical stress.

The effect of iodine-based contrast agents on the levels of radiation-induced chromosomal aberrations

The effects of iodine-based contrast agents on the repair of radiation-induced chromosomal damage were investigated employing peripheral blood from a healthy male donor. The blood samples were irradiated with 0.5-4.0 Gy 137Cs gamma rays. Contrast agents and NaCl solutions of various concentrations were added to the blood within the first 15 min or at 60 min after irradiation, and the samples were subsequently cultured for 45 h at 37 degrees C. Significantly elevated frequencies of chromosomal abnormalities caused by postirradiation treatment with hypertonic contrast agents appeared to increase with increasing hypertonicity. Elevated aberration frequencies were found to be greatest in the samples treated within 15 min of irradiation. The contrast agents had little effect if they were added at 60 min after irradiation, probably because the process of chromosome rejoining had been completed. Isotonic iodine-based contrast agents did not enhance the frequencies of chromosomal aberrations to a significant degree.

Lip form responses to changes in maxillary incisor position

A study was conducted to assess the measurement accuracy of a laser three-dimensional measurement system for measuring facial profile and to investigate the changes in lower facial morphology caused by experimental protrusion of the upper incisors, and also to examine the relationship between the changes in lip form and lip thickness. The study subjects were 24 Japanese male dental students attending Nihon University School of Dentistry at Matsudo, who had normal overbite, overjet, and normal occlusion, and a good facial profile. The mean age was 23.2 years with a range of 21.5 to 25.8 years. Three-dimensional measurements obtained by a computerized 3D laser scanning system were used to evaluate facial morphology. The measurement error of this system was less than 0.5 mm in any three-dimensional linear measurements. The stability and reproducibility of the recording procedure were evaluated. The changes in facial morphology caused by orthodontic treatment and orthognathic surgery were visualized in any direction by this three-dimensional graphic system. Lip thickness was not associated with changes in lip form. However, a relationship between the right and left corners of lip and lip thickness was noted. With regard to the ratio of changes in hard tissue and lips, the value of the original position for a 4 mm protrusion was not the same as that for a 4-8 mm protrusion. Also, the correlation of the changes in both groups was very low. The changes in lip thickness were associated with changes in stomion position, which in turn were related to the vertical change in the upper lip.

Effects of in vitro cellular aging on alkaline phosphatase, cathepsin activities and collagen secretion of human periodontal ligament derived cells

It is believed that the degree of periodontal tissue breakdown and tooth loss increase with age. In periodontal tissues which are gingiva, periodontal ligament (PL), alveolar bone and tooth cementum, the PL which is soft connective tissue, lies between the tooth cementum and alveolar bone, having the primary function of tooth support, and maintaining the homeostasis of supporting tissues, as well as providing the healing process. We therefore investigated the effects of in vitro cellular aging on alkaline phosphatase (ALP), cathepsin activities and collagen secretion from human PL cells obtained from 18-23 year-old patients' teeth. ALP, cathepsin activities and collagen secretion may play important roles in the remodeling and maintaining of periodontal tissues. To investigate the life span of PL cells, the cells were sequentially subcultivated. The maximum population doubling level of the PL cells in the present experiment was 22-25 passages. Investigating some important biological activities of the PL cells at different passage levels (6-7, 30% of life span to 17-20, 75% of life span), ALP activity and collagen secretion were found to have significantly decreased while cathepsin B and L activities significantly increased with cellular aging. Since these biological activities in human PL cells tend to be more catabolic with increase in cellular aging, the increase in periodontal breakdown with age may be partly related to the catabolic changes of the PL cells themselves.

[Combination therapy with hormonal, radiation and chemotherapy for stage C prostate cancer]

To improve the effectiveness of treatment for patients with stage C prostate cancer, therapy in combination with hormonal, radiation and chemotherapy was given for the initial period, and there after, hormonal therapy was continuously administered to 18 patients with chemotherapy and three patients without it. At the Social Health Insurance Medical Center, between May 1988 and August 1991, 21 patients were diagnosed to have stage C histologically confirmed adenocarcinoma of the prostate. The average age of the patients was 69.0 years. The tumor was well, moderate and poorly differentiated in 5, 6 and 10 patients, respectively. As hormonal therapy, orchiectomy was performed on 19 of the 21 patients. Furthermore, 11 patients were administered estramustine phosphate, 9 chlormadinone acetate, and one diethylstilbestrol diphosphate. As, radiation therapy, all patients were treated with AP-PA parallel opposing technique to small pelvis with a 12 cm x 12 cm treatment field (44-45 Gy) combined with conformation radiotherapy to prostate (20-26 Gy). Chemotherapy was performed using either one or a combination of the following; cis-diamminedichloroplatinum, adriamycin, cyclophosphamide, 5-fluorouracil, methotrexate and etoposide. The observation period was 54.5 months on the average. Recurrence was observed in 3 patients, for all of which the sites were at bone. The 5-year non-recurrence rate was 90.4% by Kaplan-Meier's method. There were 4 deaths, three were due to prostate cancer and one to gastric cancer. The 5-year cumulative survival rate by Kaplan-Meier's method was 90.5%. In conclusion, this treatment was effective for stage C cases of prostate cancer.

MRI findings of dysplasia epiphysealis hemimelica

We report a boy with dysplasia epiphysealis hemimelica of the knee, particularly emphasizing MRI findings. When he was 14 months of age, plain radiography exhibiting juxta-articular soft tissue mass with small, punctate, calcified foci did not warrant the definitive diagnosis, while MRI clearly demonstrated osteocartilaginous overgrowth of the femoral epiphysis. The epiphyseal mass mostly showed the same signal intensity as normal cartilage but contained low signal spots corresponding to calcified foci. The cartilaginous cap was depicted as a mottled area of high intensity on a T2-weighted image. When the patient was 4 years of age, this ossified mass was resected surgically and pathologically identified as osteochondroma incorporated into the epiphysis.

Relationship between cranial base and maxillofacial morphology

The aims of this study were to investigate the relationships between the cranial base and maxillofacial morphology in Japanese crania, and to examine the differences between Class I and Class II samples. Data were obtained from 46 male Japanese crania from the collection of the Jikei University School of Medicine (Tokyo). The sample represents populations which would have lived during the last 100 years. A principal component analysis of linear and angular measurements showed that the anterior and posterior cranial base, and the cranial base angle were associated in different ways with different aspects of maxillofacial morphology. Variation in the anterior cranial base was associated with differences in facial height, lower facial height, bicondylar breadth, ramal height, and ramal width, while posterior cranial base length was correlated with bizygomatic breadth. The cranial base angle was negatively correlated with SNA (r = -0.46) and SNB (r = -0.59), and positively correlated with the palatal and occlusal plane angles. There were significant differences between Class I and Class II specimens in palatal width, SNA, ANB, and the palatal plane angle, but no significant difference in cranial base length or angle. The evidence suggested that cranial base shape and size was related to facial length, inclination of the maxilla, and both maxillary and mandibular prognathism.

Inhibition of prostaglandin E2 and interleukin 1-beta production by low-power laser irradiation in stretched human periodontal ligament cells

It is well-known that orthodontic treatment usually causes some discomfort and pain to the patients. Recently, it has been reported that low-power laser irradiation is effective in reducing the pain accompanying tooth movement. However, the mechanism of such pain relief cannot be elucidated. Since high levels of prostaglandin (PG) E2 and interleukin (IL)-1 beta are found in the periodontal ligament (PDL) during tooth movement, and both factors are involved in the induction of pain, the effects of low-power laser irradiation on PGE2 and IL-1 beta production in stretched human PDL cells were studied in vitro. The PDL cells, derived from healthy premolars extracted for orthodontic treatment, were utilized for experiments. Cells were seeded in flexible-bottomed culture plates, and the bottom of each plate was elongated (18% increase) under vacuum at 6 cycles per min for 1, 3, or 5 days. The stretched cells were irradiated with a Ga-Al-As low-power diode laser (60 mW) once a day for 3, 6, or 10 min (from 10.8 to 36.0 J) for 1, 3, or 5 days. PGE2 and IL-1 beta levels in the medium were measured by radioimmunoassay. In response to mechanical stretching, human PDL cells showed a marked elevation in PGE2 production in a time-dependent manner. IL-1 beta production was also elevated, but this remained constant. The increase in PGE2 production was significantly inhibited by laser irradiation in a dose-dependent manner. The increase in IL-1 beta production was also significantly inhibited by laser irradiation, although the inhibition was only partial.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of different magnitudes of tension force on prostaglandin E2 production by human periodontal ligament cells

Periodontal ligament (PDL) cells are known to produce prostaglandin E2 (PGE2) in response to mechanical stress. However, the rate of PGE2 production from PDL cells in response to different magnitudes of tension forces has not been examined. This study, therefore, was undertaken to determine the effect of different magnitudes of tension forces on PGE2 production and inositol trisphosphate (IP3) levels in PDL cells in vitro. Human PDL cells were cultured on flexible-bottomed plates and placed on a Flexercell strain unit. Cells were flexed at six cycles (5-s strain, 5-s relaxation) at six steps of tension force (9, 12, 15, 18, 21, 24% increase in surface area) for 5 days. PGE2 production and IP3 levels were determined by radioimmunoassay. There was a 6- and 25-fold increase in the rate of PGE2 production by cells exposed to low (9%) and high (24%) tension forces, respectively, and these increases were tension force-dependent. Tension force also induced increases in the intracellular levels of IP3 that did not seem to be directly related to the production of PGE2. The different rates of PGE2 production by PDL cells in response to different magnitudes of mechanical stress may be of importance in PDL and alveolar bone metabolism.

Relationship between attachment of the superficial masseter muscle and craniofacial morphology in dentate and edentulous humans

Previous studies have described the importance of the interaction between the masticatory muscles and the craniofacial skeleton in the control of craniofacial growth. This study describes the attachment and orientation of the superficial masseter muscle and its relationship with craniofacial morphology in dentate and edentulous subjects. Data were obtained from lateral cephalometric radiographs of a total of 31 cadavers in which the superficial masseter muscle had been defined with liquid barium. The results provide evidence that the morphology of the superficial masseter muscle in the gonion region differed significantly between dentate and edentulous subjects, with the masseter being 2.7 mm wider and the gonion-anterior muscle border distance being 4.0 mm greater in dentate subjects. The complex relationship between craniofacial morphology and the dimensions and inclination of the superficial masseter muscle were most clearly evident in dentate subjects where the position of the anterior border was related to ramus dimensions and mandibular and occlusal plane angles. The association is much less clear in edentulous subjects where normal function was disturbed. In general, age was not a significant determinant of variation in superficial masseter muscle dimensions and orientation.

Stimulation by interleukin-1 of interleukin-6 production by human periodontal ligament cells

Interleukin-1(IL-1), a cytokine present in the gingiva and crevicular fluid of patients with periodontitis and in the periodontal ligament (PDL) of experimentally moved teeth, has multiple biological activities, including the ability to elicit bone resorption. Interleukin-6, also found in the gingiva of patients with periodontitis, may induce osteoclastic bone resorption through an effect on osteoclastogenesis. Here IL-6 production and its gene expression in response to recombinant IL-1 beta were examined in primary cultures of PDL cells. IL-1 beta stimulated IL-6 production by these cells in a dose- and time-dependent manner; this increase in IL-6 production was much higher than that in human gingival fibroblasts. In situ hybridization, using a synthetic oligonucleotide DNA probe of the IL-6 gene, revealed that most PDL cells expressed IL-6 mRNA in response to IL-1 beta treatment. The finding that IL-6 is produced by PDL cells and is regulated by IL-1 beta has revealed a potentially important mechanism for controlling alveolar bone resorption.

[Ewing's sarcoma in the retroperitoneum]

The patient was a female aged 18. Hematuria was discovered at an examination two years previously at which time the patient was complaining of right lumbar pain. The patient visited our hospital with a chief complaint of right abdominal tumor in June, 1988. A retroperitoneal tumor, 77 X 45 mm in size, was observed by CT and ultrasonic examination, and the right kidney was in hydronephrosis. An operation was performed in September, 1988, based on a diagnosis of retroperitoneal tumor and hydronephrosis. The tumor was seen to have involved the right ureter. Subsequently the tumor was surgically removed; right total nephroureterectomy and partial cystectomy were performed at that time. The removed tumor was 90 X 70 mm in size and 120 g in weight; it was histopathologically diagnosed as extraskeletal Ewing sarcoma. A systemic examination was carried out postoperatively, but no abnormalities were observed. As of September, 1990, the patient had had no recurrence and was being kept observation on an outpatient basis. There have been a total of 210 case reports regarding extraskeletal Ewing sarcoma published worldwide, including our case and 26 cases in Japan, so far as we know. However those of a lesion of retroperitoneal origin are extremely rare, numbering only 11 cases worldwide and 2 Japan. Herein we report our case of extraskeletal Ewing sarcoma with reference to the other 209 cases reported in the literature to date.

Hyperthermic purging in vitro of murine leukemia cells (MK-8057): surviving fractions of normal and leukemic stem cells and the long-term survival of mice injected with the post-hyperthermic leukemia cells

Hyperthermic purging of leukemic cells has been applied in clinical trials, although an accurate evaluation system to compare the effect on leukemia cells with that on normal hemopoietic cells has not been established. We evaluated the heat-sensitivity of murine leukemia cells, MK-8057, and compared differences in heat-sensitivity between surviving fractions of leukemic stem cells (leukemic spleen colony-forming units, L-CFU-S) and normal hemopoietic stem cells (spleen colony-forming units, CFU-S). Using the spleen colony assay, the survival fraction of L-CFU-S was compared with that of CFU-S after various hyperthermic treatments. One of the most efficient conditions, that is, hyperthermia at 42 degrees C for 3 h, allowed only 0.17% of L-CFU-S to survive, whereas 26.5% of normal CFU-S survived. Hyperthermia at 44 degrees C for 45 min further reduced the L-CFU-S (0.13%); however, the relative ratio of L-CFU-S to CFU-S was less than that at 42 degrees C for 3 h, because there was a larger reduction at 44 degrees C in normal CFU-S (5.1%). Recipient mice injected with MK-8057 cells treated with hyperthermia survived longer in proportion to the decreasing number of surviving L-CFU-S injected. This extension of the survival of recipient mice given MK-8057 cells after hyperthermia was also proportional to the estimated survival fraction of L-CFU-S. The survival fraction of MK-8057 cells after hyperthermia that was independently calculated through the extended survival of the recipients showed a good correlation with the surviving fraction of L-CFU-S, seen as the leukemic spleen colonies, at a correlation coefficient of r = 0.985. The number of surviving mice receiving the post-hyperthermic MK-8057 cells and the number of L-CFU-S calculated to have been injected had a relationship based on a Poisson distribution. Thus, the calculated results imply that the hyperthermia proportionally targets L-CFU-S, which are the only cells responsible for killing the recipient mice.

Progressive shrinkage of the thalamus following middle cerebral artery occlusion in rats

Permanent middle cerebral artery occlusion in rats results in infarction in the ipsilateral cortex and caudate nucleus-putamen. In this ischemia model, severe shrinkage of the ipsilateral half of the thalamus was observed several months after surgery. We examined the serial profile of this phenomenon in 40 rats at intervals from 2 weeks to 6 months after the operation. The area of the ipsilateral half of the thalamus as a percentage of the area of the contralateral half was 87% at 2 weeks, 77% at 1 month, 54% at 3 months, and 54% at 6 months. Such severe morphologic change distant from the original ischemic focus has not been reported in models of experimental focal ischemia. Retrograde degeneration is thought to play an important role in this phenomenon.

[Consideration to the experimental study on the rapid palatal expansion in the rat]

The purpose of this study is to clarify the most suitable position and method to investigate bone formation in the mid-palatal suture after rapid palatal expansion in the rat. 10 of 8 week-old Wistar rats were employed to observe the structure of the normal mid-palatal suture at the line connecting the incisors, the anterior end of the anterior palatine foramen, the line bisecting the anterior palatine foramina, and the line of the 1st molars. A mid-palatal suture of 8 week-old Wistar rats was expanded laterally for 6 days by means of maxillary incisor expansion apparatus with a spring of 60 g load. After beheading, soft X-ray picture of the skull was taken to observe the suture. The maxilla was removed and decalcified sections (frontal section) were prepared. They were stained with hematoxylin and eosin for microscopy. The mid-palatal suture was observed at 4 levels to the lines drawn as follows; the line running through the centers of incisors (A), the line running the anterior ends of the anterior palatine foramen (B), the line running through the center of the anterior palatine foramen (C), and the line running through the centers of the 1st molars (D). At the opposing margins of A and B, the suture was composed of two layers; the layer of osteoblasts and the layer of interconnecting Sharpey's fibers. At C, the suture was curved and the layer of Sharpey's fibers were made up with longitudinal as well as transverse fibers.(ABSTRACT TRUNCATED AT 250 WORDS)

[Multiple cerebral venous angiomas associated with mixed pial and dural arteriovenous malformation]

Venous angioma is a relatively rare entity of vascular malformations of the brain and usually found as a solitary lesion. Cases of multiple lesions and/or coupled with other vascular malformations are extremely rare. We present the first case of multiple supratentorial venous angiomas associated with mixed pial and dural arteriovenous malformation (AVM) fed by the posterior cerebral artery, the occipital artery and the posterior meningeal artery.